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    Fabrication and application research progress of fiber-based self-powered electronic skins
    LÜ Xiaoshuang, LIU Liping, YU Jianyong, DING Bin, LI Zhaoling
    Journal of Textile Research    2022, 43 (10): 183-191.   DOI: 10.13475/j.fzxb.20220404509
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    This review introduces the categories, characteristics, and preparation processes for constructing materials with applications for electronic skins, from the perspective of composition structure of the electronic skins with tactile sensing capability. The compelling features of breathable fiber materials serving as substrate layer, electrode layer, and sensing layer in electronic skins were highlighted, in view of the poor air permeability of current dense film-based and rubber-based electronic skins that easily lead to itching during long-term wearing. The working mechanisms of piezoelectric and triboelectric electronic skins were introduced, which are not only able to achieve real-time pressure sensing response, but also able to harvest the ambient mechanical energy and convert it into electricity to power themselves. These are conducive to the fabrication of miniatured, lightweight, and flexible wearable devices. The research progresses in fiber-based self-powered electronic skins in the fields of motion monitoring and medical detection were comprehensively summarized in terms of preparation methods, performance characterizations, and practical applications. The existing challenges and future development directions of fiber-based self-powered electronic skins were extensively discussed.

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    Preparation of dendritic nanofiber membrane induced by hyperbranched quaternary ammonium salt and its properties
    YAO Ying, ZHAO Weitao, ZHANG Desuo, LIN Hong, CHEN Yuyue, WEI Hong
    Journal of Textile Research    2022, 43 (10): 1-9.   DOI: 10.13475/j.fzxb.20211202809
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    In order to develop membrane materials with high efficiency filtration performance, this research prepared polyvinylidene fluoride (PVDF) dendritic nanofiber membranes using hyperbranched quaternary ammonium salt (HBP-HTC) as a branching promoter based on electrostatic spinning technology in one step. The influence of the spinning process on the forming structure of the fiber membrane was explored. The mechanical properties of the dendritic nanofiber membrane were analyzed and its air filtration performance was measured. The results showed that the nanofiber membrane prepared with HBP-HTC has more dendritic structures than the membrance prepared with small molecule quaternary ammonium salts due to the abundant quaternary ammonium groups on the surface of HBP-HTC, which has a stable enrichment effect on charge. When the mass fraction of PVDF was 12%, the quaternary ammonium groups was 0.1 mol/L, and the spinning voltage was 25 kV, the dendritic coverage of the fabricated fiber membranes was as high as 78.32% and demonstrated good mechanical properties. The filtration efficiency of the prepared nanofiber membrane reached 99.995% at the thickness of 40 μm, while the pressure drop is 122.4 Pa.

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    Lightweight clothing detection method based on an improved YOLOv5 network
    CHEN Jinguang, LI Xue, SHAO Jingfeng, MA Lili
    Journal of Textile Research    2022, 43 (10): 155-160.   DOI: 10.13475/j.fzxb.20210809306
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    In order to further reduce the occupation of computing resources by the clothing object detection model based on deep learning, an improved lightweight clothing object detection method, MV3L-YOLOv5, was proposed. The MobileNetV3_Large is used to construct the backbone network of YOLOv5, and the label smoothing strategy was introduced to enhance the generalization ability at the training stage of the model. The data augmentation technology was used to make up for the unbalanced number of images of different clothing categories in the DeepFashion2 dataset. Experimental results show that the model volume of MV3L-YOLOv5 is 10.27 MB, the floating-point operations is 10.2×109 times, and mean average precision is 76.6 %. Comparing with YOLOv5s, which is the lightest network in YOLOv5 series, MV3L-YOLOv5 is compressed in the model volume by 26.4 %, reduced the floating-point operations by 39 %, and improved accuracy by 1.3 %. Experimental results in the improved algorithm show that the detection performance is notably improved, and the model is lighter and more suitable for deployment in devices with limited resources.

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    Research status and development trend of perspective preparation technologies and applications for textiles
    WU Jing, JIANG Zhenlin, JI Peng, XIE Ruimin, CHEN Ye, CHEN Xiangling, WANG Huaping
    Journal of Textile Research    2023, 44 (01): 1-10.   DOI: 10.13475/j.fzxb.20220706210
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    Significance Chemical fiber is a necessary component of human productivity and daily living. Since the 1970s, China's chemical fiber industry has developed quickly, and China has led the world in production of chemical fiber for almost 20 years. In 2021, China's chemical fiber output has reached 60.25 million tons, or more than 70% of the total amount produced worldwide. Currently, the development of high performance, functional, and intelligent textile products has drawn considerable attention as consumer demand has increased significantly. The production of raw resources, technological advancement, and the application fields of functional products are all significant variables. The future development of the textile industry is undoubtedly very important, and in order to be clear about the future development direction, it is thus crucial to summarize the possible and potential development trend of novel technologies and improved products with higher performance and wider application fields in future textile industry on the basis of the existing technologies and problems.
    Progress Currently, significant obstacles still exist to the growth of the textile sector, which are mostly seen in the following four aspects: 1) shortage of resources for fiber raw materials; 2) increase of processing costs; 3) products elevation. Middle and low-grade products no longer have any advantages, the production and processing capability is forced to migrate out of China, and new and high-grade products are being developed and produced; 4) absence of innovative technology. The developed synthetic biological method and genetic engineering technology can successfully prepare bio-based raw materials like 1, 3-propanediol and lactic acid in order to avoid the significant consumption of petroleum-based raw materials and the competition between bio-based raw materials and grain. Fiber material forming technology is moving progressively in the direction of an effective multi-flow, sustainable, green, and intelligent technology introduction. Furthermore, the fiber forming technology is more advanced to achieve the accurate building of multiple fiber structures. A greater range of applications can be met by the expansion and performance improvement of fiber structures. Application of clothing in the direction of development for high performance, minimal loss, light weight, and multifunctional clothing. Additionally, textiles have new uses in the development of biomedical materials, environmental protection filtration materials, and agricultural production materials. The innovation products are multi-functional and more intelligent, and can realize the active adaptation of structure and performance in varied application conditions.
    Conclusion and Prospect The development of textile industry and textile technology has played a crucial role in the evolution of human civilization. Today in the 21st century, the textile industry is no longer just a conventional industry to meet the needs of human clothing. Its technological development is more advanced and cutting-edge: 1) the innovation of raw materials. Innovations in feedstock technology such as the development of bio-based feedstocks have made fiber products more environmentally friendly. Pure organic polymers are no longer the only type of fibrous matrix materials; in addition, inorganic, metal, and organic-inorganic hybrid fiber materials are now covered. 2) forming technology. Fiber material forming technology is gradually moving toward an effective multi-flow, environmentally friendly, and sustainable processing process. Infinite creative potential exists for final applications thanks to the advancement of fiber forming technology and the evolution of fiber on a multidimensional scale. 3) intelligent manufacturing. The adoption of intelligent manufacturing, complete process automation, information technology, and digitalization can significantly increase the productivity of the textile sector. 4) more diverse applications. In the future, textiles could be used in apparel, wearable textiles, household textile items, and extremely innovative fields including biomedicine, the environment, energy, agricultural production, building, and transportation, among others, with the focus on intelligence and function. The textile sector has demonstrated multifaceted inventive growth that will open up more room for human civilization and technology advancement.

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    Research on breast shape of young females using characteristic parameters
    ZHONG Zejun, ZHANG Beibei, XU Kaiyi, WANG Ruowen, GU Bingfei
    Journal of Textile Research    2022, 43 (10): 148-154.   DOI: 10.13475/j.fzxb.20210907607
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    In order to study young female's breast shape discrimination for improving the bra sizing system for the Chinese females, a definition method for defining breast boundary was proposed to ensure the consistency of breast shape measurement indexes. Raw data was collected by scanning 140 female college students using the [TC]2 scanner, and 28 breast measurement values including height, width, angle, and arc were extracted. Analysis of data was conducted by integrating coefficient of variation and correlation analysis methods, and 6 major parameters affecting breast morphology were identified as clustering indexes. K-means cluster was used to categorize the breast shapes into groups from the 3-D shape of the breast, and the breast shape was subdivided by the ratio of gathering degree and the young females' breast shape was divided into 9 categories. Based on the classification results on breast morphology, Fisher criterion function was used to verify the samples. The results show that the accuracy of overall judgment of the initial sample data based on morphological discrimination rules is as high as 97.1%, which shows that this criterion method has high accuracy, providing new ideas for the breast morphology research, and has a positive effect on the progress in the brassiere industry in China.

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    Review in functional textiles for personal thermal and moisture comfort management
    CHENG Ningbo, MIAO Dongyang, WANG Xianfeng, WANG Zhaohui, DING Bin, YU Jianyong
    Journal of Textile Research    2022, 43 (10): 200-208.   DOI: 10.13475/j.fzxb.20210401609
    Abstract389)   HTML43)    PDF(pc) (1609KB)(227)       Save

    With the aim of achieving improved individual comfort and reduce energy consumption in providing cooling and heating, textiles regulating heat and moisture exchange between human body and its surroundings are a promising solution. This paper reviews the researches on functional textiles for heat and moisture management. The review started with the introduction of personal heat and moisture comfort management mechanisms, followed by summarizing six common advanced functional textiles that can be used for personal heat and moisture management, these being the radiative thermoregulation textiles, phase change thermoregulation textiles, smart response textiles, thermal conductive textiles, thermoregulation textiles for energy conversion, and moisture management textiles. The research progress in functional textiles was summarized on the basis of different heat and moisture management mechanisms and their potential applications in several fields, taking that fabric regulation of microclimate between body and ambient heat and moisture balance is the key to individual comfort. The review pointed out that the current advanced functional textiles for heat and moisture management still have problems such as difficulties in scale preparation, functional singleness, lack of intelligence and absence of systemic heat and moisture comfort evaluation, and it is foreseen that advanced textiles for personal heat management, energy harvesting technology and integration of flexible electronic devices are the future development trend of smart clothing.

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    Review on thermal-drawn multimaterial fiber optoelectronics
    ZHANG Jing, HUANG Zhiheng, NIU Guangliang, LIANG Sheng, YANG Lüyun, WEI Lei, ZHOU Shifeng, HOU Chong, TAO Guangming
    Journal of Textile Research    2023, 44 (01): 11-20.   DOI: 10.13475/j.fzxb.20220606310
    Abstract328)   HTML37)    PDF(pc) (8985KB)(176)       Save

    Significance With the rapid development of textile engineering and material science, intelligent fibers and related fabrics have become the preferred carriers for wearable electronics with their advantages in softness, lightness, and breathability. A variety of fiber manufacturing technologies has been developed, enabling conventional fibers with new capabilities such as environmental/physical/chemical sensing, logical computing, human-machine interaction, and so on. Among these manufacturing techniques, the thermal drawing process can be adopted to fabricate multimaterial optoelectronic fibers, providing an innovative research for intelligent fibers and fabrics. By enriching fiber structures, materials and post-treatment techniques, thermal-drawn fibers can be integrated with multiple functions such as multi-parameter sensing, temperature regulation, and information interaction, broadening the application scenarios of fibers.
    Progress Thermal-drawn multimaterial optoelectronic fibers are generally drawn from fiber preforms with a fiber drawing tower. The external forms, internal structures, and materials of fiber preforms can all be designed with great flexibility according to the applications and functions. The diameters of fibers are typically in the micron range, and the structures of the fibers are consistent with the preform rods. In addition, fiber post-treatment techniques, such as thermal treatment and cold-drawing process, can further enrich and modify the structures, giving more ways to improve the functionalities of fibers.
    With these advanced fiber drawing and processing technologies, micro- and nano-structured fibers can be achieved. For example, a low-loss CO2 laser-propagated photonic bandgap fiber has been achieved with a hollow core surrounded by a solid multilayer structure of high refractive-index contrast. The fiber has a large photonic bandgap and omnidirectional reflectivity. Nanowires, structural micro- and nanospheres, nanorods, and porous fibers have also been produced in a scalable way by the in-fiber fluid instability phenomena, cold-drawing deformation, and salt leaching techniques. Moreover, surface micro-nano imprinting technology has been utilized to construct specific fibers with micro/nano-surface patterns.
    The richness of structures and materials gives fibers a variety of advanced functionalities, such as sensing, energy management, neural probing, and information interaction. For sensing, the thermal-drawn fibers have been achieved with acoustic, photoelectric, strain, and chemical sensing. For energy management, fiber-based devices are enabled with the functions of passive temperature regulation and energy generation/storage. Thermal-drawn fibers have also been widely used as neural probes because of their flexibility, small size, and conductive property. In addition, semiconductor diodes and integrated circuits have been integrated into thermal-drawn fibers successfully, which empowers the fibers with the abilities of logical computing and information interaction.
    Conclusion and Prospect This work focuses on the research progress and application fields of thermal-drawn multimaterial fiber, reviews the regulation of the micro/nanostructures inside the fibers by thermal drawing, and discusses their applications in sensing, energy, biology and others with recent studies.
    However, there are still some limitations to thermal-drawn multimaterial fiber optoelectronics. 1) Only a few of materials and structures are investigated and applied into the system. 2) The mechanical properties and comfort of wearing of thermal-drawn fibers need to be improved. 3) It is still difficult to integrate multiple functions into one fiber. 4) The abilities of logical calculation and data management of the thermal-drawn fibers should be enhanced.
    The future research trends of thermal-drawn multimaterial optoelectronic fibers are discussed from five aspects: more material selection, complex fiber structure, textile processing, multi-function integration, and artificial intelligence. It is foreseen that current mono-functional thermal-drawn multimaterial optoelectronic fibers can be improved for higher integrations, better mechanical properties, and more intelligence. These advanced fibers can also be combined with conventional textiles to enable their functionalities, comfort of wearing, and applicability to scenarios.

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    Cotton impurity image detection based on improved RFB-MobileNetV3
    XU Jian, HU Daojie, LIU Xiuping, HAN Lin, YAN Huanying
    Journal of Textile Research    2023, 44 (01): 179-187.   DOI: 10.13475/j.fzxb.20210911809
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    Objective The complexity of deep convolutional neural network models makes it difficult for embedded devices to meet real-time online detection, and this research works on an improved RFB-MobileNetV3(RFB-MNV3) method for cotton impurity detection.
    Method Firstly, the MNV3 redundant network structure was reduced according to the construction of high-precision lightweight network model and the premise of ensuring high detection accuracy. Secondly, the 3×3 convolutional layer replaced the 5×5 convolutional layer and the 1×3+3×1 convolutional layer was folded to replace the 3×3 convolutional layer as the improved RFB module deployed to the pooling layer of the improved MNV3 to enhance the online detection speed and accuracy of cotton hash. Finally, the algorithm before and after the improvement and other detection algorithms were compared.
    Results The influence of training times, different lighting changes and different camera shift poses on the model was investigated using the test set. The improved RFB-MNV3 network model was iteratively trained to improve the average accuracy of cotton impurity classification. The specific classification detection effect under the improved RFB-MNV3 model showed that the detection accuracy was 83%-96% as suggested by the average AP values of the detection results for each category, among which the best effect was achieved in identifying cotton seeds with 96% accuracy (Fig.11). The value of the improved RFB-MNV3 algorithm reached 88.15%, indicating that the accuracy and score (the score of impurity detection under the optimized algorithm) have reasonably high stability, i.e. the model can better classify cotton impurity detection and can basically meet the actual industrial production needs. The detection results were compared with those of the MNV3, YOLOv3, VGG16 and ResNet34 network models (Tab.2). The detection time of the improved RFB-MNV3 model reached 0.02 s, and the online detection accuracy of the improved RFB-MNV3 model reached 89.05%, which is 6.83% higher than MNV3 and 8.48%-17.32% higher than other network models. The average accuracy mean combined with the accuracy and recall rates can be utilized to evaluate the comprehensive performance of image classification. It can be seen that the improved RFB-MNV3 model has a mean accuracy value that is 6.31% higher than MNV3 and 8.76%-17.72% higher than other networks.
    Conclusion The new network is improved on the basis of the MNV3 detection network, while the improved RFB-MNV3 module is combined to achieve the purpose of reducing the model parameters without basically losing the model accuracy, solving the problem that the complexity of the deep convolutional neural network model makes it difficult for the embedded device to meet the real-time online detection. The model proposed can effectively achieve the detection of lint images, while the model detection efficiency is high and the storage occupied is small, which can provide the necessary technical support for the development of embedded devices for lint image detection.

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    Nondestructive testing on damage of carbon fiber composites using ultrasonic C-scanning
    FANG Zhouqian, MIAO Peiyuan, JIN Xiaoke, ZHU Chengyan, TIAN Wei
    Journal of Textile Research    2022, 43 (10): 71-76.   DOI: 10.13475/j.fzxb.20210903306
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    With respect to the hole defects of the carbon fiber composites, the ultrasonic C-scan imaging detection technology was used to scan the specimens with holes, and the position of the defects obtained C-scan were analyze. The holed specimens were scanned, and the appearance of the scanned image was analyzed for causing reasons. Cluster analysis was performed to establish the relationship between the actual area of the defect and the detection area, and reflection scanning and scanning electron microscopy were carried out for the holed specimens and the composite delamination was analyzed according to the scanning waveform and electron microscopy. The research results show that there is a one-to-one correspondence between the C-scan image and the position of the composite material defect, and that when the hole diameter is larger than the beam width of the focusing probe, the edge of the hole does not affect the beam penetration and energy loss. The work indicated that the ultrasonic C-scan imaging detection technology can further verify holes and delamination defects.

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    Preparation and properties of polypyrole/silk fibroin conductive nanofiber membranes
    YU Yangxiao, LI Feng, WANG Yuyu, WANG Shanlong, WANG Jiannan, XU Jianmei
    Journal of Textile Research    2022, 43 (10): 16-23.   DOI: 10.13475/j.fzxb.20210906708
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    In order to develop tissue regeneration materials with certain electrical conductivity, we prepared silk fibroin nanofiber membranes using electrospinning and further polypyrrole/silk fibroin conductive nanofiber membranes by in-situ oxidative polymerization. The effect of spinning parameters on the surface morphology of nanofiber membrane was studied. The electrical conductivity of nanofiber membrane was tested by the four-point probe. FT-IR spectrometer was used to characterize the chemical structure of nanofiber membrane. The results showed that silk fibroin nanofiber membranes have an even surface with less beads, with an average fiber diameter of (520.70±140.81) nm, when solution concentration was 0.16 g/mL, flow rate 0.2 mL/h, voltage 20 kV, rotating speed 1 000 r/min. Polypyrrole/silk fibroin conductive nanofiber membranes was prepared by in-situ oxidative polymerization, and it retains its original nano fiber structure, and the electrical conductivity is (0.44±0.07) S/cm, when the pyrrole concentration was 0.3 mol/L, dopant concentration 0.3 mol/L, the ratio of fixed pyrrole to oxidant 1∶2, and the polymerization time 6 h.

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    Research progress in aerogel materials application for textiles
    ZHAO Lunyu, SUI Xiaofeng, MAO Zhiping, LI Weidong, FENG Xueling
    Journal of Textile Research    2022, 43 (12): 181-189.   DOI: 10.13475/j.fzxb.20210501210
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    In order to clarify the definition of aerogel and explore its application value in textiles, the evolution of the definition and the domestic and international research status of aerogel-based textiles were reviewed and summarized. The preparation processes of three main application methods of aerogel in textiles, i.e., gel integral molding method, thermal bonding method and coating method, as well as their advantages and disadvantages were analyzed in detail. Focusing on the four application forms of aerogel-based textiles, including thermal protection textiles, warm and cold-proof textiles, super-hydrophobic textiles and noise and sound insulation textiles, this paper expounded the action mechanism of aerogel and pointed out the problems currently in these application forms. Finally, the review concluded that enhancing mechanical properties, optimizing material compatibility, reducing preparation cost and promoting intelligent transformation would be the significant development directions of aerogel materials for the textile field in the future.

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    Preparation and properties of phosphorus-silicon modified flame retardant and anti-dripping polyester fiber
    REN Jiawei, ZHANG Shengming, JI Peng, WANG Chaosheng, WANG Huaping
    Journal of Textile Research    2023, 44 (02): 1-10.   DOI: 10.13475/j.fzxb.20220809410
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    Objective Polyester fibers are flammable with a large number of molten droplets and smoke emission when burning. This research aims to improve the flame retardant properties of polyester fibers through the addition of phosphorus and silicon flame retardants, and to prepare polyester fibers with better flame retardant properties for fire safety in end uses.
    Method The phosphorus-silicon flame retardant masterbatch was prepared by blending diethyl hypophosphite flame retardant, macromolecular silicone and polyester. Then, the phosphorus-silicon flame retardant masterbatch was added to the polyester according to an optimized mass fraction, and the flame retardant and anti-dripping polyester fiber was produced by melt spinning. The mechanical properties, thermal properties and flame retardant properties of the flame retardant polyester were characterized and analyzed by using scanning electron microscope, compound filament strength meter, differential scanning calorimeter, thermogravimetric analyzer, ultimate oxygen index meter and Raman spectroscopy.
    Results The diethyl hypophosphite flame retardant selected in this work is found to be able to dehydrate the polyester surface into char, and the macromolecular silicone enhances the graphitization of the char layer, forms an orderly and stable char layer, enhances the flame retardant polyester flame retardant properties and inhibits the formation of molten droplets. Accordingly, the amount of smoke formed by combustion decreases, and the morphology of the char layer of the samples after combustion is shown in Fig. 5, and the results of the char layer structure stability study were shown in Fig. 6. It is discovered that macromolecular silicone mainly plays a role in the cohesive phase flame retardant process when polyester burns, forming a synergistic effect with phosphorus-containing flame retardant, generating an effective physical barrier, impeding the transfer of combustible gases, oxygen and heat, and inhibiting the occurrence of combustion reactions. The flame retardant polyester fiber spun by adding 3% diethyl hypophosphite flame retardant and 0.77% macromolecular silicone, the test results for the flame retardant properties of the modified samples are showed that the limiting oxygen index reached more than 31%, the vertical combustion test grade reached V-0 level, inhibiting the formation of molten droplets of polyester fiber during combustion, hence reducing the risk of secondary combustion brought about by the molten droplet phenome-non(Tab. 7).
    Conclusion The flame retardant synergistic effect between phosphorus and silicon elements improved the spinnability of the flame retardant polyester fiber, and the modified polyester fiber has good flame retardant and anti-dripping properties. This work proved that the phosphorus-silicon element synergy is helpful to improve the flame retardant properties of polyester fibers, and provides ideas for the subsequent preparation of flame retardant polyester fibers by using different structural flame retardants from the viewpoint of conformational relationship and processing performance.

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    Preparation of polyamide 6-based elastic fibers and its structure and properties
    YANG Hanbin, ZHANG Shengming, WU Yuhao, WANG Chaosheng, WANG Huaping, JI Peng, YANG Jianping, ZHANG Tijian
    Journal of Textile Research    2023, 44 (03): 1-10.   DOI: 10.13475/j.fzxb.20211005610
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    Objective The binary acid method can be used for preparing polyamide 6 (PA6) based elastomer easily and efficiently, but stoichiometric number balance is strictly required when feeding. Once the molecular mass of the soft and hard segments is determined, the proportion of the soft and hard segments cannot be changed, which limits the development of functional products.The paper is to propose a new polymerization method based on the binary acid method to flexibly adjust the relative molecular weight and proportion of the soft and hard segments of PA6-based elastomers and to provide the basis for the subsequent research of PA6-based elastomers.

    Method On the basis of the binary acid method, ethylene glycol is introduced to participate in the esterification and ester exchange reaction between polyamide 6 and polyether segments. With the ethylene glycol component, the system can ensure the balance of stoichiometry and adjust the ratio of soft and hard segments more flexibly to obtain the PA6-based elastomer. All reactions for preparing the PA6-based elastomer were performed in a 10 L reactor with a vacuum pump, a vacuum tube, and a nitrogen cyllinder.

    Results It can be seen from the infrared spectra of the polymer that there are ester bonds in the product, indicating that ethylene glycol and polyethylene glycol were introduced into the system in the form of copolymerization (Fig.3). The structure of PA6 based elastomer (Fig.4), and combined with the peak (Fig.5), six bonding structures of PA6-based elastomer were made known. The relative integral area of the peak was introduced into equations (5) and (6), and it was proved that the molecular mass and PEG segment content were consistent with the design. The contents of low molecular extractants in PA6 based elastomer (Tab.4). The low content of low molecular extractants was conducive to the subsequent melt spinning of PA6-based elastomer. When the molecular weight of the soft and hard segments was given, the crystallization enthalpy and melting enthalpy of PEG segments would increase with the increase of the content of PEG segments, and the crystallization enthalpy and melting enthalpy of PA6 segments would decrease accordingly (Fig.7). With the same content of soft and hard segments, when the molecular mass ratio of hard segment to soft segment (Mn,PA6/Mn,PEG) increases, the melting and crystallization temperatures of PA6 and PEG segments would increase (Fig.8). It can be seen that the smaller the PEG content, the greater Mn,PA6/Mn,PEG, the higher the thermal stability of the resulting elastomer (Tab.5). It can be seen that the characteristic peaks of PA6 based elastomers were consistent with those of PA6, indicating that the crystal structure of this series of PA6-based elastomers was solely determined by PA6 chain segments(Fig.9). It can be seen that the elasticity of PA6 based elastic fibers increases with the increase of the PEG segment content, while the fracture strength and fracture elongation of fibers decrease sharply (Fig.10). It is evident that with the decrease of PEG segment content and the increase of Mn,PA6/Mn,PEG, the main chain structure of PA6 based elastic fiber is similar to that of pure PA6, and the fracture strength and elongation of the fiber increase (Tab.6).

    Conclusion After the introduction of ethylene glycol, a series of PA6-based elastomers were prepared by changing the molecular weight and feeding ratio of polyethylene glycol (PEG) to PA6, making PA6-based elastomers more designable. The molecular structure design of a series of PA6-based elastomers was verified to be effective through the analysis of 1H-NMR and infrared spectra. The thermodynamic properties, the crystal structure, the fiber mechanical properties and the elastic properties of the series of PA6-based elastomer samples were tested and analyzed. The results show that the crystal structure of PA6-based elastomer is dominated by PA6 segments. With the increase of the PEG segment content, the elastic recovery of fiber increased, and the strength and elongation of fiber decreased. Compared with PA6 fibers, elastic fibers with above 20% PEG content shows higher resilience at high constant elongation (≥10%), the elastic recovery rate are increased by up to 17.5%. PA6-based elastic fiber is found to possess encouraging comprehensive properties, among which the strength is 1.57 cN/dtex, the elongation is 106.89%, and the elastic recovery at 10% constant elongation is 94.3%.

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    Research progress in bulletproof flexible textile materials and structures
    CHU Yanyan, LI Shichen, CHEN Chao, LIU Yingying, HUANG Weihan, ZHANG Yue, CHEN Xiaogang
    Journal of Textile Research    2022, 43 (12): 203-212.   DOI: 10.13475/j.fzxb.20210607910
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    In view of the contradiction between lightweight and high protection of soft flexible impact resistant textiles, research progress in new fibers and film materials, fiber surface modification and structural design are reviewed. The theoretical strength, preparation methods and macro preparation problems about new fibers and film materials, including graphene and carbon nanotube are analyzed. The modification methods and impact resistance effects of shear thicken fluids and nano inorganic materials on the fiber surface are examined. The advantages and disadvantages of single-layer fabric structure and laminated structure have been analyzed and the application prospects of aerogel composite structure and hard-soft bionic structure used for impact resistance are expounded. It is pointed out that on the basis of fulfilling the requirements of impact resistance, coordination between comfort and impact resistance can be achieved through the combined design of surface modification, fabric structure, interlayer structure, and the hybrid use of hard and soft structures. The macro quantitative defect-free preparation of high-purity graphene and carbon nanotube fibers or films overcome the technical bottleneck for much lighter impact resistance textiles in the future.

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    Preparation and sensing response characterization of polydopamine modified reduced graphene oxide/polypyrrole conductive fabrics
    WAN Ailan, SHEN Xinyan, WANG Xiaoxiao, ZHAO Shuqiang
    Journal of Textile Research    2023, 44 (01): 156-163.   DOI: 10.13475/j.fzxb.20210601908
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    Objective Conductive fabric can be easily fabricated into smart clothes comfortable to wear. However, a common problem is that a large mismatch in mechanical properties between the conductive layer and the fabric substrate affects the performance of the flexible sensors. In order to improve the interfacial adhesion between the conductive layer and fabric, and construct an effective contact conductive network to obtain excellent sensing response characteristics, a reduced graphene oxide (RGO) and polypyrrole (PPy) flexible sensor was prepared by surface modification of polyester-spandex knitted fabric with polydopamine (PDA).
    Method A knitted fabric substrate was modified by PDA, a PDA-RGO fabric was prepared by impregnation-drying and chemical reduction, and PPy was self-assembled on the PDA-RGO fabric via in-situ polymerization. The PDA modified RGO/PPy conductive fabric sensor was characterized and analyzed by Fourier infrared spectrometry (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), a self-made KTC sensor box, a four-probe square resistance tester, a Martindale abrasion and pilling tester and a universal tensile testing machine.
    Results The PDA fabric, PDA-RGO fabric, PDA-RGO/PPy fabric and RGO/PPy fabric were prepared. A comparative study of the influence of PDA modification on the electrical conductivity and sensing properties of knitted fabrics was then carried out. The results indicated that the PDA filled the gaps among the yarns of the knitted fabric and improved the continuity of the conductive layer. The square resistance of the conductive fabrics showed that PDA enhanced the conductivity of the conductive fabric. The square resistance of the PDA-RGO/PPy fabric was about 0.08 kΩ/□. The PDA-modified knitted fabric had a strong adsorption to the conductive layer. RGO and PPy had a synergistic effect on the electrical properties, and the conductive fabrics containing RGO/PPY had better conductivity than fabrics with a single conductive component. The conductive layer of the PDA-modified RGO/PPY fabric had increased interfacial bonding by virtue of the bonding of the PDA. The change in resistance after rubbing was smaller for the PDA-RGO/PPy fabric than for the RGO/PPy fabric (Fig.5). The study of fabric sensing characteristics showed that PDA-RGO/PPy fabric had better sensing properties than RGO/PPy fabric. The stretching range of the PDA-RGO/PPy fabric flexible sensor was 0%~130%, the sensitivity was increased to 39.1, and the response time was 0.06 s. Moreover, the peak value of the relative change of resistance of PDA-RGO/PPy fabric was essentially the same for different stretching rate (Fig.6), proving the accuracy of this flexible sensor. This phenomenon can be explained by the fact that PDA deformed the conductive layer synchronously with the fabric substrate. The PDA-RGO/PPy fabric flexible sensor can be worn on joints such as fingers, wrists and knees to monitor motions. The fabric flexible sensor captures the motions steadily and outputs the relative change of resistance (Fig.11).
    Conclusion The results of above characterizations indicate that the interfacial adhesion between the PDA-modified fabric and RGO/PPy is significantly improved, and the conductive network is constructed more continuous. Compared with unmodified fabrics, the modified fabrics has improved durability and rubbing resistance. The experimental results show that the sensing mechanism of the fabric sensor is mainly the disconnection mechanism and crack propagation. Monitoring of different joint motions can be achieved according to the resistance change curve and the data can be used for building human joint motion sensing systems. In the future, the conductive properties of the PDA-RGO/PPy fabric flexible sensor can be optimized by controlling the combination options and shape of the conductive materials for further adjusting the surface morphology of the conductive layer.

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    Research progress in high efficiency and low resistance air filter materials
    YANG Jizhen, LIU Qiangfei, HE Ruidong, WU Shaohua, HE Hongwei, NING Xin, ZHOU Rong, DONG Xianglin, QI Guishan
    Journal of Textile Research    2022, 43 (10): 209-215.   DOI: 10.13475/j.fzxb.20210305007
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    In order to develop high efficiency and low resistance air filtration materials, solve the imbalance between filtration efficiency and filtration resistance in the current research, and further improve the quality factor for filtration materials, this paper reviews the relevant research on nanofiber membrane, melt-blown filtration materials and high-temperature resistant needle filter mat in recent years.The research status of electret filtration materials, micro-nano structure filtration materials, gradient structuring and finishing methods to improve the filtration efficiency of materials are reviewed.The influencing factors of charge storage capacity of materials are analyzed and discussed. The preparation methods of micro-nano structure materials are summarized. The advantages and disadvantages of gradient structuring and finishing methods for improving filtration efficiency were compared. It is concluded that the electret and micro-nano structured filtration materials will draw great attention from researchers because of their great potentials in the future field of air purification.

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    Research progress in smart fabrics for thermal and humidity management
    CHEN Jiahui, MEI Tao, ZHAO Qinghua, YOU Haining, WANG Wenwen, WANG Dong
    Journal of Textile Research    2023, 44 (01): 30-37.   DOI: 10.13475/j.fzxb.20220705708
    Abstract264)   HTML24)    PDF(pc) (6025KB)(158)       Save

    Significance With rapid development of today's social population and the increasing scarcity of fossil energy, a huge contradiction arose between the surge in energy consumption, e.g., from air conditioning, and the global goals of "carbon peaking" and "carbon neutrality". The large amount of greenhouse gas emissions caused by air-conditioning, refrigeration and heating have also become an urgent problem to be solved. Therefore, it is necessary to seek a new method for effectively adjusting the thermal and moist comfort of the human body so as to reduce the energy consumption caused by air conditioning. Textiles can also play a role in managing human comfort in daily life, but would mainly rely on the thickness of clothing to regulate human body temperature. In order to better meet the modern day requirements for life comfort, the active adjustment of smart textiles has demonstrated the potential for adjusting the human body's thermal and moist comfort, thereby reducing the energy consumption in the process of cooling and heating by air conditioning. Under the premise of the "double carbon" goal, this has could be a promising solution.
    Progress This review summarizes the research progress in adjusting the thermal and moist comfort of the human body by using smart fabrics. The principle of regulating the thermal and moist condition of the human body through the fabric is introduced. In addition, the researches and mechanisms of the current study on regulating the thermal and moist comfort of the human body by means of fabric materials or fabric structures have been summarized. Coating or combining high-performance materials was adopted to prepare thermal and moist comfort fabrics aiming to regulating human body temperature. High infrared reflection materials such as silver and titanium dioxide, high thermal conductivity materials such as boron nitride nanosheets (BNNSs), and high infrared transmission materials such as polyethylene (PE) are proposed. All of these high-performance materials can be used for raising or decreasing the body temperature. The review also introduces the thermal and moist comfort adjustment of smart fabrics caused by different fibers and fabric structures, such as thermal fabrics made of porous fibers, moisture-absorbing and quick-drying fabrics caused by asymmetric structures, and intelligent adjustment fabric that can respond to changes in fabric pore size caused by external temperature and humidity. Finally, this review paper analyzed and discussed the current difficulties and challenges in smart fabrics with different fabrication methods.
    Conclusion and Prospect The smart fabric that can manage thermal and humid conditions of human body is necessary and the key is energy shortage. However, the performances of the thermal management, humidity management or thermal and humidity management of the recent smart fabric are directly affected and limited by the materials. Few high-performance functional materials can be utilized to fabricate smart fabrics. In addition, the main technical means of preparing thermal and moist comfort smart fabrics are coatings and material composites. However, the stability of coatings, the compatibility of composite materials, and the difficulty of industrial production limit the development of thermal and moist comfort smart fabrics. Therefore, it is necessary to prepare new fibers that can respond to external heat and humidity stimuli, so as to realize the preparation of fabrics that can intelligently regulate human body temperature and humidity. Additionally, the ease of construction, preparation, and large-scale production of fibers can reduce the cost of smart fabric production. Finally, the current preparation methods and functional principles of intelligent thermal-moist comfort fabrics are summarized, and a low-cost and large-scale preparation method for intelligent thermal-moist comfort fabrics is proposed by technological innovation of fibers.

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    Research progress in fabric defect detection based on deep learning
    WANG Bin, LI Min, LEI Chenglin, HE Ruhan
    Journal of Textile Research    2023, 44 (01): 219-227.   DOI: 10.13475/j.fzxb.20211105509
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    Significance With the development of science and technology, the improvement of product quality is highly demanded. Although the technologies used in producing textile products have undergone revolutionary advancement which contributes to the textile quality dramatically, defects in textile products such as fabrics remain to be a reality. Fabric defect detection plays an important role in textile industry, and fabric defect detection technology based on deep learning has been paid more and more attention. This paper reports a research and development progress in fabric defect detection based on deep learning.
    Progress Deep learning is mainly composed of four steps, i.e., defining model and loss function, training the model, finding optimization method and loop iteration. The research focus for fabric defect detection method based on deep learning mainly includes deep learning models such as convolution neural network (CNN) and automatic encoder (AE). The stack denoising automatic encoder based on Fisher criterion introduces deep learning into this field for the first time, which provides a new idea for the application of deep learning to the field of defect detection. Convolution neural network has achieved good results in the field of image recognition because of its strong nonlinear fitting ability. More precision-based detection algorithms based on candidate regions and more speed-based algorithms based on regression analysis are present. While the advantages of convolution neural network is exploited, other methods are used for exploring the possibility of combined use of models, and provide new ways for defect detection.
    Conclusion and Prospect Fabric defect detection methods based on deep learning in recent years are reviewed and summarized, and the effects of different models are compared in detail. Advantages, disadvantages and applicable scope of each model are analyzed, and future development of fabric defect detection method based on deep learning model is prospected. Deep learning models can improve the detection efficiency, but still have some deficiencies. In order to optimize the accuracy of fabric image defect detection, breakthrough should be made from the following aspects in the future. 1) High quality data sets should be established. 2) Specific evaluation criteria need to be established. 3) The applicability should be extended. A single detection method often has limitations, but when different defect detection methods are utilized to deal with different detection needs, the detection results are often different, therefore hybrid methods would have better applicability.

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    Influence of yarn twist on properties of cotton/spandex/silver wire core spun yarns
    LI Long, WU Lei, LIN Siling
    Journal of Textile Research    2023, 44 (01): 100-105.   DOI: 10.13475/j.fzxb.20211100606
    Abstract253)   HTML8)    PDF(pc) (4291KB)(44)       Save

    Objective The application of conductive yarns in flexible and wearable smart devices has attracted extensive attention from many researchers. The key objectives of this research included preparing elastic and conductive yarns with excellent textile properties such as color attributes, wearing comfort, and environmental friendliness.
    Method In order to prepare a conductive yarn with favorable textile properties, cotton roving, silver wire and spandex were selected as the raw materials. By designing the feeding of raw materials and attaching a positioning device between the front roller and the yarn guide in the ring spinning machine, an elastic conductive core yarn with spandex as the core, silver yarn and cotton fibers as the sheath with cotton fibers on the surface of the yarn was produced to investigate the influence of yarn twist on the elasticity, conductivity, abrasion resistance and breaking strength of the core spun yarn. Using the model of silver wire tightly wrapped around the spandex surface (Fig.2), the theoretical value of the length of silver wire wrapped around the spandex surface in the core spun yarn with different yarn twist was calculated.
    Results The experimental results showed that the elasticity of core spun yarn varied with yarn twist, and the elasticity of core spun yarn at constant elongation and at constant load was larger at a yarn twist of 70 twist/(10 cm) than yarns with other yarn twists (Fig.4). In the unstretched straight state of the core spun yarn, the measured resistance of the yarn increased with the increase of yarn twist (Tab. 2), because increasing the yarn twist causes the pitch of the wrapping silver wire to decrease and the length of the silver wire in the unit length of core spun yarn to increase. At 10% elongation of the core spun yarn, the measured resistance of the yarn was smaller than that of the same length of core spun yarn in the unstretched state, and the difference between the measured resistance of the same length of core yarn in the elongated state and in the unstretched state was smaller at a twist of 75 twist/(10 cm) (Tab. 3). At 10% elongation of the core spun yarn, the measured resistance of the core yarn per unit length was greater than the theoretical resistance of the straight silver wire, indicating that when the core spun yarn elongation is at 10%, the silver wire in the yarn was not at the completely straightened state, and the yarn elongation caused the pitch of the silver wire over the spandex became larger and the actual length of the silver wire in the core spun yarn per unit length became smaller. At 75 twist/(10 cm), the core spun yarn showed higher wear resistance. Because when the twist is too high, the torque of cotton fibers in the yarn is high, the fiber stress increases, causing the cotton fibers to be easily worn off and the wear resistance of the core spun yarn is reduced.
    Conclusion The elasticity and conductivity of core spun yarn are closely related to the yarn twist level. For the actual core spun yarns, the silver wire is not tightly wrapped around the surface of the spandex core, and there are cotton fibers between the spandex and the silver wire, causing the theoretical resistance value per unit length to be smaller than the measured resistance value. Since cotton fibers can be dyed in different colors and the cotton fibers are distributed on the surface of the core spun yarn, this work can be used to further develop elastic and conductive yarns in different colors and comfortable to wear for the transmission of electrical signals in smart wearable textiles, powering electronic textiles, and electrical heating devices. The preparation process of this core spun yarn is environmental friendly. In the application of flexible and wearable smart devices, such elastic and conductive core spun yarsn have a good development prospect.

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    Influence of heat-treatment tension in post-processing on structural properties of high modulus low shrinkage industrial polyester fibers
    CHEN Kang, CHEN Gaofeng, WANG Qun, WANG Gang, ZHANG Yumei, WANG Huaping
    Journal of Textile Research    2022, 43 (10): 10-15.   DOI: 10.13475/j.fzxb.20210803807
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    This research investigates the influence of heat-treatment tension on structural properties of high modulus low shrinkage (HMLS) industrial polyester fibers in post-processing. HMLS industrial polyester fibers was subjected to heat treatment with various tensions (0-0.10 cN/dtex) at 150 ℃ for 5 min. The conformational changes of the samples before and after the heat treatment were analyzed, and the structural factors regulating their properties were discussed. The results show that with the decrease of pre-tension, the breaking strength remains basically unchanged, the tenacity decreases slightly, the initial modulus and the tenacity at the specific elongation of 5.0% decreased obviously, and ultimate elongation increased significantly. The microstructure changes caused by the heat-treatment mainly occur in the amorphous chains, causing lower orientation in the amorphous region, lower trans conformation content, smaller lamellar long period and smaller amorphous thickness. The presence of pre-tension can effectively offset the shrinkage stress of the fiber, decreasing the mobility of molecular chains in the amorphous region, and the degree of mechanical properties and structure changes in the amorphous region is reduced.

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    Preparation and properties of poly(butylene succinate)/silk sericin blend fiber
    XIA Yu, YAO Juming, ZHOU Jie, MAO Menghui, ZHANG Yumei, YAO Yongbo
    Journal of Textile Research    2023, 44 (04): 1-7.   DOI: 10.13475/j.fzxb.20211111107
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    Objective Poly (butylene succinate) (PBS) is a synthetic biodegradable polymer and silk sericin is a natural biodegradable polymer. PBS fiber can be prepared by melt spinning process, which is applied in textile industry as raw material. Silk sericin can be used as moisturizer in skincare and textile industries. To improve the skin-friendliness of PBS fiber, PBS and silk sericin was mixed by melt blending, then the blend fiber was prepared by melt spinning process.
    Method After vacuum drying at 80 ℃ for 4 h, the PBS and silk sericin were melt blended using an internal mixer at the rotation rate of 60 r/min for 25 min. The mixing temperature of the PBS/silk sericin blends was set to 140 ℃, and the weight ratio of PBS/silk sericin is shown in Tab. 1. After that, the PBS/silk sericin blend fibers were spun through a single-screw extruder at 160 ℃. Then, the fiber was cooled in a water bath at room temperature. The extrusion speed was 1.95 g/min, the drawing speed was 3.60 m/min, and the draw ratio was 4.
    Results The scanning electron microscopy (SEM) of the cross-section of the PBS/silk sericin blend fiber is shown in Fig. 1. The rough cross-section of PBS/silk sericin blend fiber indicates poor compatibility between PBS and silk sericin. There were small voids on the cross-section of the blend fibers, the number of voids would increase with the rise of silk sericin mass fraction. The XRD pattern of PBS/silk sericin blend fiber is shown in Fig. 3 and the crystallinity of PBS is listed in Tab. 2. With the increase of silk sericin mass fraction, the crystallinity of the blend fiber decreases. It seems that the crystallization process of PBS was obstructed by the dispersion of silk sericin in the fiber. The mechanical property of PBS/silk sericin blend fiber is shown in Fig. 4. Tensile strength and elongation at break of the blend fiber decrease when the silk sericin mass fraction increases, and the elongation at break of PBS fiber is 212.1%. However, for the blend fiber when the mass fraction of silk sericin became 15%, the elongation at break of was only 8.9%, this value meets the requirement of textile requirement. Hence, the overlarge elongation at break of PBS fiber can be reduced with the existence of silk sericin. The saturated moisture regains of the PBS/silk sericin blend fibers is shown in Fig. 6. It can be found that the saturated moisture regain of the blend fiber is improved with the increase of silk sericin mass fraction. For the blend fiber when the silk sericin mass fraction is 15%, the saturated moisture regain is 3.90%. This value is similar to the saturated moisture regain of polyamide 6 fiber (saturated moisture regain is 3.95%) with good hydrophilic property. The improved saturated moisture regain of the blend fiber is not only related to the hydrophilic group of silk sericin, but also associated with the increase of amorphous region area in the blend fiber. The weight loss rate of PBS/silk sericin blend fibers after soil burial test is shown in Fig. 7. The weight loss rate of the blend fiber after 6 weeks during the soil burial test is up to 53.6%. When silk sericin is degraded by microorganisms firstly, the specific surface area increases, which is beneficial to the contact between PBS and microorganisms. Then, the degradation rate of PBS is also accelerated.
    Conclusion In this research, the PBS/silk sericin blend fibers were prepared by melt spinning method. The effect of PBS/silk sericin weight ratio on the morphology, mechanical strength and biodegradability was studied. The main findings are as follows,the small voids can be found on the cross-section of the PBS/silk sericin blend fibers, which is related to the weak interface force between PBS and silk sericin. For the PBS/silk sericin blend fiber when the mass fraction of silk sericin is 15%, the elongation at break is 8.9%, the saturated moisture regain is 3.90%. By contrast, the elongation at break of PBS fiber is 212.1%, the saturated moisture regain is 2.26%. The existence of silk sericin not only reduces the overlarge elongation at break of PBS fiber, but also improves the hydrophilic property. For the PBS/silk sericin blend fiber when the mass fraction of silk sericin is 15%, the weight loss rate after 6 weeks during the soil burial test is up to 53.6%. The biodegradability of PBS/silk sericin blend fiber of PBS is better than that of PBS fiber. Hence, the PBS/silk sericin blend fiber degrades quickly after use.

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    Review of new dyeing technologies for reactive dyes and disperse dyes
    WU Wei, JI Bolin, MAO Zhiping
    Journal of Textile Research    2023, 44 (05): 1-12.   DOI: 10.13475/j.fzxb.20230200802
    Abstract246)   HTML57)    PDF(pc) (4337KB)(190)       Save

    Significance Although dyeing is an important technique to give color to textiles, it also depletes resources and creates a lot of pollution. Reactive and disperse dyes are the most widely used dyes for coloring cellulose and polyester fibers, respectively. The output of two dyes accounts for more than 70% of the total output of dyes. However, reactive dyeing has problems with insufficient dye utilization, excessive use of inorganic salts, and high wastewater discharge. Meanwhile, the reduction cleaning step in the disperse dyeing process uses a lot of water and energy. The dispersants and unfixed dyes which are washed off in the reduction cleaning step will cause more difficulty in treating wastewater. Therefore, innovative dyeing techniques of two dyes that can solve these problems were reviewed in this paper.

    Progress In order to reduce the usage amount of inorganic salts in reactive dyeing technology, researchers developed a series of methods to increase the affinity of dyes and fibers, such as cationic modifications and designing macromolecular dyes. In order to improve the utilization of dyes, the wet pickup of the fabric was controlled at a low level to reduce the hydrolysis of reactive dyes. The low wet pickup dyeing technologies are foam dyeing, vacuum-dewatering aided pad-steam dyeing, spray dyeing and ″moisture fixation″ dyeing. Organic solvent (ethanol, decamethylcyclopentasiloxane, silicone oil) /water mixed solvent, liquid ammonia, and organic mixed solvent (dimethyl sulfoxide/dimethyl carbonate) were used as dyeing media to reduce the wastewater discharge. In order to solve the problem of low dyeing efficiency and high material consumption of rope dyeing, open-width dyeing technology for the cotton knitted fabric was developed. For disperse dyeing techniques, the first advancement is the development of alkali-resistant disperse dyes, which were created to solve the problem of water and energy usage during the reduction cleaning process. Owing to the same alkaline conditions, the pre-treatment and soap-washing procedures can also be combined with alkaline dyeing technology to increase production effectiveness. Secondly, the polymer dispersants with low molecular weights, no matter the synthesized copolymer anions or modified biomass polymers, were designed to make the dyes maintain nanoscales in water by grinding. Thus, the nano-scale liquid disperse dyes were prepared to improve the dyeing uptake and reduce loose color. With the use of microcapsule shells, the non-reduction clearing effect is achieved through the adhesion on the surface of the fabrics. Finally, non-aqueous media such as supercritical carbon dioxide fluid or organic solvents (decamethylcyclopentasiloxane, liquid paraffin) are used for dyeing to save water consumption.

    Conclusion and Prospect To sum up, the development of the two dyeing technologies focused on reducing the use of chemicals and wastewater emission, improving the utilization rate of dyes, and improving the efficiency of dyeing production. The use of reactive dyes with little or no salt has the problem of poor dyeing levelness or color fastness. For the wet pickup dyeing technology, the main direction of future research is to control the uniformity of dyeing and improve the color fixation rate to the highest level. The directions that need to be explored include the adaptability of open-width dyeing technology for knitted cotton textiles to thin fabric and the enhancement of process stability. Alkaline dyeing, nano liquid disperse dyeing and non-reduction clearing dyeing technologies have basically reached the industrial level, but it is still necessary to improve the categories of dyeable fabrics and improve the dyeing quality. It still needs to keep developing the theoretical framework and supporting equipment for less-water or non-aqueous dyeing technologies, whether they use reactive or disperse dyeing systems. In the future, reactive and disperse dyeing technologies continue to advance in a green and consumption-reduction direction, which will encourage the textile dyeing and printing industry to achieve the ″carbon dioxide emissions peak and carbon neutrality″ target as soon as feasible.

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    Polyethylene glycol modified thermoplastic epoxy resin and its spinnability
    HU Baoji, ZHANG Qiaoling, WANG Xu
    Journal of Textile Research    2023, 44 (02): 63-68.   DOI: 10.13475/j.fzxb.20220806106
    Abstract243)   HTML7)    PDF(pc) (5941KB)(37)       Save

    Objective Thermoplastic epoxy resin has excellent mechanical properties and can be melted and reprocessed, but its melting processing temperature is relatively high which needs to be reduced. In order to develop thermoplastic epoxy resin as textile material and to reveal its potential application in the engineering field, on the basis of studying its mechanical and thermodynamic properties, the spinning temperature of thermoplastic epoxy resin needs to be regulated by melting dispersion polyethylene glycol (PEG).
    Method Thermoplastic epoxy resin film was prepared by polymerizing-hot pressing process. The pellets of thermoplastic epoxy resin/PEG were further developed by the process of PEG melt-dispersion, and the epoxy resin/PEG filament was prepared by the process of melt-drawing. The mechanical and thermodynamic properties of thermoplastic epoxy resin film were analyzed. The influence of PEG on the spinnability of thermoplastic epoxy resin was discussed, and the mechanical and thermodynamic properties of PEG modified epoxy resin/PEG filament were analyzed.
    Results The yield stress of the thermoplastic epoxy resin film is found to reach 64.6 MPa and the breaking strain 117.4%. The storage modulus of thermoplastic epoxy resin film at 25 ℃ is found as high as 2 296 MPa, and the glass transition temperatures 100.2 ℃. PEG significantly reduces the extrusion force of epoxy resin/PEG pellets. Compared with pure epoxy resin pellets, the extrusion force of epoxy resin/PEG pellets with 5% PEG content is reduced by 870 N at 300 ℃. The spinning temperature of pure thermoplastic epoxy resin pellets is as high as 300 ℃, and the extrusion force is about 1.92 kN at this spinning temperature. With the increase of PEG content, the extrusion force of epoxy resin/PEG pellets can reach about 1.9 kN during the spinning of pure epoxy resin pellets at lower temperature. Epoxy resin/PEG pellets with different PEG content can be spun into epoxy resin/PEG filament by melt-drawing process at the mixing temperature of 290 ℃ (PEG content: 2.5%), 280 ℃ (PEG content: 5%) and 270 ℃ (PEG content: 7.5%), respectively. Compared with pure epoxy resin pellets, the spinning temperature of epoxy resin/PEG pellets with 7.5% PEG content decreased by 30 ℃. PEG also improves the drawing effect of thermoplastic epoxy resin in spinning. In terms of diameter, the diameter of the epoxy resin/PEG filament with 7.5% PEG content is 50 μm lower than that of the pure epoxy resin filament. Compared with pure epoxy resin filament, the mechanical properties of thermoplastic epoxy resin/PEG filament are significantly improved; the breaking strain and breaking stress of the epoxy resin/PEG filament with 2.5% PEG content were increased by 60% and 20 MPa, respectively. PEG reduces the glass transition temperature of epoxy resin/PEG filament. Compared with pure epoxy resin filament, the glass transition temperature of epoxy resin/PEG filament with 7.5% PEG content is reduced by 20.9 ℃.
    Conclusion Thermoplastic epoxy resin film developed in this research has high mechanical properties and thermal stability. The thermoplastic epoxy resin has the advantages of melting and reprocessing. At the same spinning temperature, the PEG-dispersed thermoplastic epoxy resin pellets have a lower extrusion force, so the spinning temperature can be controlled by the modification of PEG. The melt-dispersion process provides a new method for modification of thermoplastic epoxy resin by PEG. High spinnability of thermoplastic epoxy resin/PEG system was achieved by adjusting the spinning temperature of thermoplastic epoxy resin. The melt-dispersed PEG can significantly improve the spinnability of the thermoplastic epoxy resin, and the developed thermoplastic epoxy resin/PEG filament has higher mechanical properties.

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    Development of environmentally friendly knitted fabrics with 3-D moisture conductive structure and performance evaluation on moisture absorption and quick-drying
    WANG Yue, WANG Chunhong, XU Lei, LIU Shengkai, LU Chao, WANG Lijian, YANG Lu, ZUO Qi
    Journal of Textile Research    2022, 43 (10): 58-64.   DOI: 10.13475/j.fzxb.20210907907
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    In order to develop environmentally friendly fabrics with moisture absorption and quick-drying performance, a new 3-D moisture-conducting structure was designed to develop double-side derivative fabrics with knitted spacer structure. TencelTM and recycled polyester fibers were used, and 9 different knitted fabrics were experimented on with single-sided and double-sided constructions. Using the derivative knitted spacer structure, the fabric made from TencelTM/recycled polyester fibers was compared with the fabric of TencelTM/hollow polyester and that of TencelTM/DuPontTM Sorona®. The fabrics were tested and analyzed by moisture management method and combination tests method. The fuzzy comprehensive evaluation method was used to compare the moisture absorption and quick-drying performance of the fabrics. The results show that two test methods yield different values in the ranking of the moisture absorption and quick-drying properties. Through comprehensive analysis, 18 tex TencelTM and 33.3 tex (96 f) recycled polyester filament fabric with 3-D moisture-conducting structure has the best moisture absorption and quick-drying performance. Of the single-side fabrics, the mixed knitted fabrics of TencelTM/recycled polyester filament with flat knit structure have excellent moisture absorption and quick-drying performance. These fabrics have the potential to be used in the field of green and environmentally friendly sportswear.

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    Preparation and properties of flexible structural color film based on immobilization of liquid photonic crystals
    GAO Yiping, LI Yichen, WANG Xiaohui, LIU Guojin, ZHOU Lan, SHAO Min, SHAO Jianzhong
    Journal of Textile Research    2022, 43 (12): 1-7.   DOI: 10.13475/j.fzxb.20220301907
    Abstract233)   HTML34)    PDF(pc) (7041KB)(124)       Save

    Aiming at the poor structural stability of photonic crystal materials, photo-curable flexible monomers were used to replace conventional assembly medium of water to prepare liquid photonic crystals. A non-close-packed photonic crystals array was built with SiO2 nanospheres embedded in an elastomer polymerized by UV-curing, to produce a flexible photonic crystals film with structural stability. The optical properties of liquid photonic crystals were regulated and controlled by the volume fraction of SiO2 nanospheres in the colloidal system and the particle size of SiO2 nanospheres. It is revealed that as the volume fraction of SiO2 nanospheres increases from 22% to 40%, the average spacing between the microspheres gradually decreases, and the structure color shifts to blue accordingly, while fixing the volume fraction of SiO2 nanospheres causes the structural color shifts to red when increasing the particle size of SiO2 nanospheres from 123 nm to 178 nm. The liquid photonic crystals show bright color with high saturation, and after ultraviolet irradiation the target product of solid photonic crystals film shows obvious iridescent effect and excellent flexibility. The results indicate excellent force-induced color change performance and a promising application potential in the field of smart wearable textile materials.

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    Combustion and charring behavior of polyphenylene sulfide/graphene nanocomposite fibers
    DAI Lu, HU Zexu, WANG Yan, ZHOU Zhe, ZHANG Fan, ZHU Meifang
    Journal of Textile Research    2023, 44 (01): 71-78.   DOI: 10.13475/j.fzxb.20210908308
    Abstract230)   HTML8)    PDF(pc) (6643KB)(61)       Save

    Objective Poplyphenylene sulfide (PPS) fiber has outstanding performance and cost advantage, and can be used for making heat protection fabrics. However, when it burns, the release of heat and smoke is likely to cause damage to human body. The loose charcoal layer of its combustion will lead to high thermal and smoke release, which will cause harm to the human body. This paper is proposed to improve the structure of PPS burning charcoal layer to achieve low release of heat and smoke, and explores the applications of PPS in engineering thermal protection fabrics.
    Method Based on the obstruction effect of graphene (G) and its application in the field of flame retardancy, graphene was introduced to the PPS matrix and melting spinning was adopted to prepare PPS/G fiber. In the study, the crystallinity and orientation structures of the fiber were explored by differential scanning calorimeter and an X-ray diffractometer, and the mechanical properties of the fiber were also investigated. The PPS/G fiber was made into fabrics, cone is adopted to study the heat and smoke release of combustion, and the Raman maps and SEM images of the burning charcoal layer were adopted to clarify the changing mechanism of combustion behavior.
    Results PPS/G fibers were prepared by introducing graphene into the PPS matrix, and its microstructure and physical images suggested the characteristics of smoothness and uniformity, indicating that graphene can be well dispersed in the PPS matrix and that the fiber forming process is relatively stable. The mechanical properties of PPS/G fibers were positively influenced by graphene, and the breaking strength and elongation at break were both improved prominently (Fig.3). When the content of graphene was 0.5%, the breaking strength of the fiber was increased to 4.63 cN/dtex, while when the content of graphene was 0.3%, the elongation at break was increased to 22.01%. The improvement of mechanical properties is very beneficial for the application of fiber. In the aspect of combustion performance, the addition of graphene has a significant inhibitory effect on smoke release and heat release. The doped of graphene reduced the peak heat release rate (PHRR) of PPS from 67 kW/m2 to 28 kW/m2, the total heat release (THR) was reduced from 3.38 MJ/m2 to 1.28 MJ/m2, and the total smoke production was reduced from 1.055 m2 to 0.358 7 m2 (Fig.5). All these can be attributed to the change of combustion residual carbon. On the one hand, the quality of combustion residual carbon was significantly improved, at 800 ℃, the residual carbon content of PPS/G fiber was significantly higher than that of pure PPS (Fig.4). On the other hand, the change in structure of carbon residue was obvious. The compactness of the residual carbon is significantly increased, and the carbon layer of PPS/G fabric exhibited a non-porous nature (Fig.6). It is found that the graphitization degree of carbon layer was also significantly increased (Fig.7). The conversion of carbon content and structure is beneficial to inhibit the heat and smoke release, which is the key to the change of PPS/G fabric combustion performance.
    Conclusion With the addition of graphene, the barrier effect of carbon layer in PPS/G combustion was effectively increased, and the heat release and smoke release of PPS fabric were significantly reduced. However, for the demand of thermal protection fabric, the blending and other processes need to be further explored to achieve higher heat blockage and smoke inhibitory effects. New solutions that meet the advantages of price and heat protection need to be further sought.

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    Preparation of green-solvent-based polyamide nanofiber membrane and its air filtration performance
    ZHOU Wen, YU Jianyong, ZHANG Shichao, DING Bin
    Journal of Textile Research    2023, 44 (01): 56-63.   DOI: 10.13475/j.fzxb.20220607808
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    Objective The epidemic of COVID-19 and its variants is endangering human health. Wearing protective masks can effectively reduce the infection risk by resisting the inhalation of the polluted air containing the coronavirus. Electrospun polyamide nanofibers can be used as the core layer of protective masks and have lately received growing attention because of their high filtration performance and robust mechanical properties. However, existing electrospun polyamide nanofiber filters are usually prepared from toxic solvents which could cause severe environmental pollution and endanger workers' health, hence, their practical application should be restricted. Therefore, it is imperative to seek and develop green-solvent-based polyamide nanofiber filters.
    Method Innovative polyamide nanofiber filters were developed by direct electrospinning technique based on green solvents (Fig.1). Ethanol as the solvent and water as the nonsolvent were adopted to prepare the green-solvent-based polyamide (GSPA) nanofibers by designing spinning solutions with different ethanol/water mass ratios (i.e., 10:0, 9:1, 8:2, 7:3, and 6:4). During electrospinning process, the working voltage, tip-to-collector distance, and solution extrusion speed were set as 30 kV, 15 cm and 1 mL/h, respectively. The nanofibers prepared with the different ethanol/water ratios were denoted as GSPA-0, GSPA-1, GSPA-2, GSPA-3, and GSPA-4, respectively.
    Results It was found that water content had a great influence on the morphological structures of polyamide nanofibers (Fig.2). After introducing a small amount of water, the obtained GSPA-1 nanofibers featuring thinner diameter of 332 nm were compared to the GSPA-0 nanofibers (499 nm). The enhanced conductivity (10.5 μS/cm) of waterborne spinning solutions (Fig.3) stimulated more charges on spinning jets and led to larger electrostatic force, thus greatly elongating the jets and thinning the fiber diameter. However, with the further increment of water concentrations from 20% to 40%, the obtained fibers exhibited an increased average diameter ranging from 443 to 1 553 nm, which was mainly attributed to the larger viscosity of spinning solutions. Although water cannot dissolve polyamide, homogenous waterborne polyamide/ethanol solutions can still be obtained with different ethanol/water mass ratios within a broad area in the stable region (Fig.3). The average pore size of GSPA-1 membranes decreased by 55% compared with that of GSPA-0 membranes, contributing to high filtration efficiency. Moreover, with different concentrations (10%, 20%, 30%) of water, the fluffy structure of GSPA nanofibers were achieved with a high porosity (>80%), which would offer more passageways to transmit air rapidly. As the water concentration increased, the breaking strength of membranes increased at first and then decreased (Fig.5), and the GSPA-1 membranes exhibited the highest breaking strength of 5.6 MPa, which was believed to be related to the enhanced entanglements and contacts among the adjacent fibers because of the small fiber diameter. The GSPA-1 membranes displayed the highest filtration efficiency (99.02%) for the most penetration particles (PM0.3) by virtue of the small fiber diameter but suffered from poor permeability with a pressure drop of 158 Pa. Moreover, the GSPA-1 membranes possessed the highest quality factor of 0.029 3 Pa-1, suggesting the optimal filtration performance among different GSPA membranes. A high PM0.3 removal efficiency (>95%) was achieved for GSPA-1 filters under various airflow velocities ranging from 10 to 90 L/min (Fig.7). Compared with conventional melt-blown fibers, the GSPA nanofibers featured a smaller diameter and higher Knudsen number (Fig.8), and PM0.3 were captured mainly on the surfaces of green polyamide nanofibers (Fig.9), demonstrating the higher adsorption ability benefiting from the larger specific surface area.
    Conclusion A cleaner production of polyamide nanofibers for air filtration was proposed by direct electrospinning based on green and sustainable binary solvents of water and ethanol. For the first time, the structure including fiber diameter, porosity, and pore size of electrospun polyamide nanofibers were precisely tailored by manipulating water concentration in spinning solutions. The prepared environmentally friendly polyamide nanofiber filters feature the interconnected porous structure with the nanoscale 1D building blocks (332 nm), mean pore size (0.7 μm), and porosity (84%), thus achieving efficient PM0.3 capture performance with the filtration efficiency of 99.02% and pressure drop of 158 Pa, which could be comparable to previous toxic-solvent-processed nanofibers. Moreover, the GSPA nanofibers exhibit robust mechanical properties with an impressive breaking strength (5.6 MPa) and elongation (163.9%), contributing to withstanding the external forces and deformation in the practical assembly and usage of resultant filters. It is envisaged that the green-solvent-based polyamide nanofibers could be used as promising candidates for next-generation air filters, and the proposed waterborne spinning strategy can provide valuable insights for cleaner production of advanced polyamide textiles.

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    Influence of voltage on forming process of electrospinning beaded fiber
    GE Cheng, ZHENG Yuansheng, LIU Kai, XIN Binjie
    Journal of Textile Research    2023, 44 (03): 36-41.   DOI: 10.13475/j.fzxb.20220204006
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    Objective The sizes and morphologies of microbeads on beaded fibers will lead to great differences in the overall performance of electrospinning fiber membranes, and thus fiber membranes with specific functions can be prepared in a directional manner by adjusting the size and morphology of beads on beaded fibers. As an important factor affecting the electrospinning process, electric field has not been used as the main research object in the process of preparing beaded fibers up to date. Therefore, it is necessary to investigate the influence of applied voltage on the structure and morphology of microbeads during electrospinning.

    Method Beaded fibers were prepared by electrospinning using polystyrene (PS). Light microscope and scanning electron microscope (SEM) were adopted to observe the morphology of fibers, and the influence of applied voltage on the morphology of microbeads was studied. By observing the beaded fibers intercepted in different areas of the electrospinning jet, the evolution of beading morphology during jet whipping was explored. At the same time, the finite element simulation software COMSOL was adopted to simulate the three-dimensional electric field, bead morphology and beaded fiber movement speed. The simulation results were compared with the experimental results for model validation.

    Results Based on the simulation results of the magnitude and direction of the electric field, it is evident that the strong electric field is mainly concentrated near the spinneret. As the spinning voltage increases, greater electric field strength in the spinning area leads to stronger tensile effect of the jet. This results in a beaded shape that is approximately circular at an applied voltage of 15 kV and the beaded fibers are bent disorderedly. When the applied voltage is 25 kV, the shape of the beads is close to the spindle shape, and the fibers between the beads are more regular and orderly. As the spinning voltage increases, the speed of the beaded fibers gradually increases. When the voltage is in the range of 20 and 25 kV, the speed of the beaded fibers increases more significantly, because at larger spinning voltages, the solution in the jet is more polarized, the charge on the jet surface is higher, and the force of the electric field is stronger. Owing to the larger surface area of the bead, more charge is generated by the electric field polarization of the jet in the beaded part, which is associated to stronger the electric field drafting, resulting in a greater speed in the beaded part than the speed of the fiber part. It is clearly shown that only the Shish-Kebab (string crystal) structure exists in the linear segment of the jet. This is because the strong electric field is concentrated near the spinneret and the polymer is strongly sheared or stretched. Gradual formation of a beaded structure is observed at the end of the straight segment, because the large tensile force of the electric field causes the jet to break, the broken jet is directly drawn from the Taylor cone, and the droplet tends to contract to form beaded fibers. The result also shows that the closer is the fiber morphology intercepted in the spinning direction to the collector, the longer the electric field of the jet is subjected to and the longer the whipping disturbance action time. The shape of the beads gradually tends to spindle shape under the action of stretching.

    Conclusion In this paper, PS was used as raw material to prepare beaded fiber membranes by electrospinning method, and the evolution process of solution electro spun PS beaded fibers and the influence of spinning voltage on beaded morphology and fiber speed were investigated. The experimental results provide a theoretical basis for the controllable preparation of beaded fibers. 1) In the process of electrospinning, as the applied voltage increases, the stretching effect of the jet is more obvious, the beaded shape gradually changes from an approximate sphere to a spindle shape, and the movement speed of the beaded fiber also increases with the increase of the applied voltage. 2) The beaded structure is not formed on the linear segment of the jet, and gradually forms in the whipping zone, and the jet zone is made closer to the collector, the jet is subjected to the electric field and whipping action for a longer time, and the stretching effect of the beaded fiber is more obvious.

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    Preparation of cellulose/carbon nanotube composite fiber and its functional applications
    PU Haihong, HE Pengxin, SONG Baiqing, ZHAO Dingying, LI Xinfeng, ZHANG Tianyi, MA Jianhua
    Journal of Textile Research    2023, 44 (01): 79-86.   DOI: 10.13475/j.fzxb.20211007408
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    Objective Although cellulose fiber has advantages in high moisture absorption, good wearing comfort and low cost, its applications are limited due to its singular function and poor mechanical properties. The introduction of functional materials to give cellulose good electrical conductivity is significant to expand its applications. This research worked to disperse carboxyl-modified carbon nanotubes (CNT) evenly in the cellulose spinning dope so as to achieve high strength and good electrical conductivity of the modified cellulose fibers.
    Method In the experiment, carboxyl-modified CNT was dispersed well in sodium hydroxide/urea solution, which can dissolve cellulose at a low temperature (-10 ℃). The composite fibers with different CNT contents (mass fractions of 5%, 10%, 15%, and 20%) were prepared by a laboratory wet spinning device. Meanwhile, the microstructure, mechanical properties and electrical properties of the composite fibers were characterized by scanning electron microscope, X-ray diffractometer,infrared spectrometer,mechanical property tests, and multimeter.
    Results When the composite fibers were prepared by wet spinning, CNT maintained directional alignment because of the powerful shearing effect, which effectively improved the performance of the fiber. The surface of the cellulose fiber was smooth, while CNT was uniformly distributed along the radial direction of the composite fiber. It can be seen from the cross-sectional structure that the obtained fibers were dense when a large amount of CNT was encapsulated in the cellulose matrix to form a composite structure(Fig.4). In addition, the XRD and FT-IR spectra (Fig.5, Fig.6) indicated that hydrogen bonding interactions formed linkage between the CNT and cellulose molecular chains. The oriented structure of CNT and the hydrogen bonding interaction with the cellulose molecular chains benefited the composite fiber's mechanical properties. The stress-strain curves of the composite fibers with cellulose/CNT (C/CNT) show that the addition of CNT significantly improved the strength and stiffness of the composite fibers(Fig.7). The breaking strength was 165 MPa when the mass fraction of CNT was 20%, representing an improvement compared to the pure cellulose fiber. In addition, the composite fiber demonstrated electrical resistance of 100,3 kΩ when the mass fraction of CNT was 10%, 20%. Based on cellulose's moisture-absorbing and swelling properties, the composite fiber was further applied to the field of humidity sensing. The composite fiber exhibits excellent humidity sensitivity at room temperature, both air blowing and water immersion of the fiber resulted in detectable resistance changes (Fig.8). The electrothermal performance test revealed that the C/CNT composite fiber with a 20% CNT mass fraction exhibited excellent electrical heating performance. The temperature of the specimen rose to 62.3 ℃ within 15 s when the voltage was increased to 30 V (Fig.9).
    Conclusion A homogeneous and stable spinning solution was prepared by virtue of the fact that carbon nanotubes can be well dissolved in sodium hydroxide/urea. The C/CNT composite fibers were prepared by wet spinning. Compared with the original cellulose fiber, the good dispersion and the enhanced interface provided the composite fiber with superior mechanical properties. Combined with the scalability of the wet spinning process and the versatility of flexible conductive fibers, the related work reported in this paper provides a reference for the development and design of lightweight and flexible sensing fabrics in wearable electronics.

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    Preparation and properties of thermoplastic polyurethane meltblowns
    LIU Ya, CHENG Kewei, ZHAO Yixia, YU Wen, ZHANG Shuping, QIAN Zimao
    Journal of Textile Research    2022, 43 (11): 88-93.   DOI: 10.13475/j.fzxb.20210802806
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    In order to improve strength and elastic recovery of traditional meltblown nonwovens, a new type of elastic meltblown nonwovens was prepared from thermoplastic polyurethane (TPU). The thermal properties and rheological properties of TPU were studied, and the effects of preparation process parameters on the morphology, mechanical properties, air permeability and contact angle of TPU meltblown nonwovens were analyzed. The results show that the TPU raw material with a number average molecular weight of 33 767 g/mol, a molecular weight distribution index of 2.19 and a melting point of 159.4 ℃ has good rheological properties at 230 ℃ which is suitable for melt-blown spinning. When the average fiber diameter is 10.27 μm and the average fiber web pore size is 145 μm, the longitudinal and transverse rupture strengths of the prepared TPU meltblown nonwovens are 52 and 49 N/(5 cm), the longitudinal and transverse elongation at break are 424% and 459%, respectively. With the same web parameters, the 50% elongation recovery rate is 97%, the air permeability is 580 L/(m2·s), and the water contact angle is 110.3°, showing obvious water-repellent properties.

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    Application progress of fiber materials in flexible wearable zinc batteries
    WANG Jin, HU Kairui, ZHANG Liufei, CHEN Lei
    Journal of Textile Research    2022, 43 (10): 192-199.   DOI: 10.13475/j.fzxb.20210608108
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    In order to promote the application of zinc ion batteries with high safety and low cost in flexible energy storage devices, the paper takes fiber-based zinc ion batteries as the object and firstly clarifies the mechanism of zinc anode oxidation and transition metal oxide or oxygen positive cathode reduction in the process of charge and discharge proccess. Secondly, fibers such as carbon fiber, carbon nanofiber, carbon nanotube yarn, metal fiber and other inorganic fiber in the cathode, anode and electrolyte of flexible zinc battery are reviewed. The effects of different preparation processes, microstructure and modification strategies on the electrochemical characteristics of fiber-based flexible batteries are analyzed and compared, and the main parameters affecting its performance are defined. At last, it is proposed that the structural ordered design of fibers has a significant effect on improving the electrochemical performance of batteries, and the broad development prospect of natural fiber based electrode materials is emphasized. This paper has a positive significance for accelerating the industrial application of intelligent clothing and helping to realize the vision of "carbon peak and carbon neutralization" as soon as possible.

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    Preparation and properties of polylactic acid/thymol antibacterial fibers
    CHEN Huanhuan, CHEN Kaikai, YANG Murong, XUE Haolong, GAO Weihong, XIAO Changfa
    Journal of Textile Research    2023, 44 (02): 34-43.   DOI: 10.13475/j.fzxb.20220704510
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    Obective With the frequent occurrence of global acute infectious disease outbreaks, people are increasingly aware of individual protection. In order to protect textiles from microbial contamination and protect human health, it is important to endow textiles with antibacterial properties. However, with the gradual deterioration of white pollution, biodegradable environment-friendly polymer materials are receiving more and more attentions from researchers worldwide. Therefore, this research is committed to develop a green antibacterial fiber.
    Method Polylactic acid (PLA) with good biodegradability and the natural antibacterial agent thymol were mixed evenly using a temperature control blending device before the PLA antibacterial fibers were prepared by melt spinning. The apparent morphology, chemical structure, crystallization, thermal and mechanical properties of PLA antimicrobial fibers with different thymol mass fraction were investigated by scanning electron microscopy, Fourier infrared spectroscopy, X-ray diffraction, single fibers strength meter and comprehensive thermal analyzer. The antibacterial properties of the fibers were tested by using oscillatory flask method.
    Results After the addition of thymol, the two phases of PLA and thymol were interconnected without any obvious interface, and the two phase assembly led to good overall dispersion of thymol particles in the fibers, and excellent the compatibility between PLA and thymol, as evidenced in Fig. 2. In this study, the characteristic peak of C—H bending vibration on the benzene ring appeared at 800 cm-1. The hydroxyl group of thymol can interact with the carbonyl group in PLA to form valence bonds, indicating the existence of chemical bonding interactions between thymol and PLA matrix. Furthermore, the electron microscopic morphology results indicated that the chemical bonding between thymol and PLA promotes their dispersion, as shown in Fig. 4. As the mass fraction of thymol increases, the melting temperature of PLA antibacterial fibers gradually decreases(as shown in Fig. 5). There were two stages of thermal decomposition of PLA antimicrobial fibers. The first stage occurs in 100-200 ℃, which is due to the volatilization and thermal decomposition of thymol in the system. The second stage takes place in 310-395 ℃, and the maximum degradation rate is shown around 375-381 ℃, and the mass loss gradually increases up to 99.28%. This is because of the decomposition of PLA macromolecules and short chain segments, and oligomers and lactide esters are produced during the melting process, as shown in Fig.6. With the increase of thymol mass fraction, the crystallinity of PLA antibacterial fibers gradually increases(as shown in Fig.7). When the mass fraction of thymol is 15%, the elongation at break of PLA antibacterial fibers can reach 320.98%, which was 90 times more than that of pure PLA fibers, and the flexibility is greatly improved, and these are shown in Fig. 8 and Tab. 3. Moreover, the higher the thymol mass fraction, the better the antibacterial properties of antibacterial fiber's. When the mass fraction of thymol is greater than or equal to 15%, the antibacterial rate of PLA antibacterial fibers becomes higher than 99.99%, which can inhibit the growth of Escherichia coli and Staphylococcus aureus completely. Besides, the antibacterial property of thymol on Staphylococcus aureus is better than that on Escherichia coli, as shown in Tab. 4.
    Conclusion During the fiber formation process, thymol will adhere to the outer surface of the fibers to show antibacterial effect. With the increase of thymol mass fraction, the elongation at break of antibacterial PLA fibers shows a trend of rapid increase and then slowly decrease, and the elongation at break of PLA antibacterial fibers with thymol mass fraction of 15% can reach 320.98%, which is 90 times of pure PLA fibers. This indicates that the addition of thymol is beneficial to improve the flexibility of PLA. In addition, with the increase of thymol mass fraction, the melting temperature of PLA antimicrobial fibers gradually reduce and the crystallinity gradually increase, which illustrates that the addition of thymol promotes the formation of the α' crystalline form of PLA. When the mass fraction of thymol is more than 15%, the antibacterial property of PLA antimicrobial fibers reaches more than 99.99%, which can completely inhibit the growth of Staphylococcus aureus and Escherichia coli. In summary, the addition of thymol can impart excellent antibacterial properties to the fibers, improve the wearability of PLA fibers, and make them better used in textiles. Subsequent studies can optimize the wearability by improving the spinning conditions and processes to achieve the mass production of antibacterial fibers.

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    Preparation and characterization of polylactic acid nanofiber drug loaded medical dressings
    LI Liang, PEI Feifei, LIU Shuping, TIAN Sujie, XU Mengyuan, LIU Rangtong, HAI Jun
    Journal of Textile Research    2022, 43 (11): 1-8.   DOI: 10.13475/j.fzxb.20210908508
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    In order to construct a self-degradable, antibacterial, anti-inflammatory, light, thin and soft medical dressings conducive to wound healing, nanofiber drug loaded dressings based on polylactic acid (PLA) was prepared by electrospinning technology with different mass fractions of amoxicillin. The microstructure, wettability, drug release, antibacterial and self-degradation properties of nanofiber films were analyzed by means of scanning electron microscope, infrared spectrometer, X-ray diffraction, contact angle tester and UV spectrophotometer. The results indicate that the PLA nanofiber dressings possess porous structure and the diameter of dressing fiber decreases with the increase of drug loading. When the drug loading is 3%, the average diameter of dressing fiber is 684 nm. There is no chemical reaction between amoxicillin and polylactic acid, suggesting that negative modification did not occur for the amoxicillin. Moreover, the wettability and antibacterial properties of drug loaded PLA nanofiber dressings are enhanced with the increase of drug loading. The antibacterial rate of nanofiber dressings with 3% drug loading is up to 91% for staphylococcus aureus. In addition, polylactic acid nanofiber dressings represent excellent in-vitro degradation performance, drug release ability and stable release rate, which are necessary for wound dressings.

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    Rapid determination of quinoline in textiles
    YIN Zhe, ZHAO Hailang, XU Hong, MAO Zhiping, TAN Yujing
    Journal of Textile Research    2022, 43 (12): 125-130.   DOI: 10.13475/j.fzxb.20211107106
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    In order to reduce the extraction time from small amount of organic reagent, a rapid analytical method for the determination of quinoline in textiles by pyrolysis/thermal desorption-gas chromatography-mass spectrometry(Py/TD-GC-MS) was established. This method requires no sample processing, and the quinoline is thermally desorbed directly in the pyrolysis/thermal desorption device before entering the GC-MS for qualitative and quantitative determination. To solve the problem of quinoline volatilization before and during the analysis process, polyvinyl chloride(PVC) was added as the adsorbent of quinoline to improve the accuracy of quinoline standard solution analysis. The thermal desorption temperature was 240 ℃, the thermal desorption time was 6 s, the heating rate was 50 ℃/min and the interface temperature was 300 ℃. The results show that the linear range of the method was 10-1 000 mg/kg, the correlation coefficient was 0.994, the limit of detection was 3.520 mg/kg, the limit of quantification was 11.760 mg/kg, the spiked recoveries were 90.02%-102.07%, and the relative standard deviation was 1.27%-4.53%. All these suggest that this method is suitable for rapid determination of quinoline in textiles.

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    Research progress in one-way water transport textiles and their applications
    WANG Hongjie, HU Zhongwen, WANG He, FENG Quan, LIN Tong
    Journal of Textile Research    2022, 43 (11): 195-202.   DOI: 10.13475/j.fzxb.20210905108
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    In order to further promote the one-way water transport technique with textiles and to expand its applications, a detailed overview on research, development, and applications of one-way water transport textiles is presented. This paper summarized the research progress in the one-way water transport textiles in recent years. The designed principles and the common preparation methods based on the surface energy gradient, development process, and the latest research progress were systematically introduced and discussed, and then the advantages and disadvantages of different preparation methods were reviewed and analyzed. The application fields were classified and discussed, including clothing, fog collection, oil-water separation, sensors and air filtration. The roles of one-way water transport textiles played in different applications were explained. Future developments and problems of the one-way water transport textiles were highlighted. Possible solutions were put forward aiming at the limitations of the preparation of one-way water transport textiles, and future development directions were discussed for theoretical and technical references to expand the applications of one-way water transport textiles.

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    Research progress in display units fabricated from textiles
    SHI Xiang, WANG Zhen, PENG Huisheng
    Journal of Textile Research    2023, 44 (01): 21-29.   DOI: 10.13475/j.fzxb.20220606609
    Abstract207)   HTML31)    PDF(pc) (15066KB)(147)       Save

    Significance As the window of human-machine interaction, demands on displays have become an important driving force for the development of the information society. The development of display technology ranges from the early three-dimensional bulky cathode ray tube display to flat-panel liquid crystal display, and now to the two-dimensional thin-film organic light-emitting diode display, and the displays are becoming flexible and lightweight by reducing the thickness of the device. With the rapid development of emerging fields such as wearable devices, smart interactions and the Internet of Things, displays are required to fit the irregular surface of the human body, match the human body in mechanical properties and remain stable under three-dimensional deformation. Additionally, future displays should be permeable for long-term comfort in the applications of human-machine interaction and health monitoring. Textile is an indispensable part of our daily life, and integrating displays into textile is an ideal way to realize new displays that is highly flexible, adaptive to complex deformation, and permeable.
    Progress Light-emitting devices are the basic components of displays. Dynamic images in displays are realized by controlling light-emitting devices according to the driving program. Until now, three types of textile light-emitting device structures have been developed. They are textile-based planar light-emitting devices, light-emitting fibers, and warp-weft interwoven light-emitting devices.
    Textile-based planar light-emitting devices are prepared by attaching flexible thin-film light-emitting devices to the textile substrate or depositing active materials layer by layer on the textile substrate to obtain light-emitting devices. Owing to the wide investigation on materials and fabrication of planar light-emitting devices, it is easy to achieve high luminance and efficiency in textile-based planar light-emitting devices for better display performance. However, the modulus of film materials is always higher than the modulus of textiles. The mismatch between the mechanical properties leads to reduced flexibility of the textile, and the devices can the easily peeled off from the textile or fade in performance during deformation.
    The two-dimensional thin film light-emitting devices are converted into one-dimensional light-emitting fibers, which are the building blocks of textiles. Light-emitting fibers can be woven into textiles without sacrificing the inherent permeability and flexibility of textiles. Through the design of material and device structure, meter-length light-emitting fibers were realized based on AC electroluminescent material. Light-emitting fibers with good mechanical stability and flexibility can be woven into textile to display pre-designed weaving patterns. However, this is a significant limitation because simply based on pre-designed patterns, it is almost impossible for them to satisfy the display applications like computers and cell phones.
    For real displays consisting of an array of pixels, the pixels are individually controlled in real time for dynamic change. A strategy is proposed to build micron-scale light-emitting devices at the warp and weft interwoven points. Composite warps that load luminescent materials and transparent conductive wefts were developed, and the textile pixels were formed by contacting two fibers during weaving. This method unifies the textile and the display device in function, structure, and fabrication method. High-resolution display in the textile was achieved by applying digital signals to warps and wefts.
    Conclusion and Prospect In the past decade, many efforts are made to design materials, device structures, and fabricate methods for displaying textiles. High stability, flexibility, and permeability of displaying textiles are achieved by developing one-dimensional fiber devices, and pixel displays with high resolution and large-area integration are facilitated by developing warp-weft interwoven devices. However, the following problems remain to be solved to promote the practical application of displaying textile.
    1) Luminescent materials are the basis for high display performance. Unique highly curved structures of fibers lead to new requirements for the composition, structure, film forming method and mechanical stability of light-emitting materials.
    2) Full-color display is indispensable for human-machine interaction. In planar display, full color is realized by mixing the light emitting from three adjacent light-emitting devices in red, green, and blue. Fiber-shaped light-emitting devices are curved light sources. The space distribution of emitted light from fiber devices is different from that from planar devices, which demands new principles of color mixing.
    3) Resolution is a key parameter for display quality. The resolution of displaying textiles is still far below that of the commercial displays. It is challenging to uniformly load the luminescent materials on superfine fiber and reveal the light-emitting mechanism of interwoven light-emitting devices in the size of tens of microns.
    4) Systematic integration is the foundation of practical application. In order to integrate displaying textiles with other fiber devices such as battery fibers and sensing fibers, problems should be solved to connect fiber electrodes in high bonding strength and stable electrical conductivity under deformation. Matching of electrical parameters among textile devices should also be investigated for the reliable operation of the textile system.

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    Methods for converting 3-D styles to 2-D patterns for fully formed garments
    LU Lisha, JIANG Gaoming
    Journal of Textile Research    2022, 43 (10): 133-140.   DOI: 10.13475/j.fzxb.20210808508
    Abstract205)   HTML9)    PDF(pc) (3395KB)(67)       Save

    In order to further understand the knitting principle of whole garments and develop more styles with different shapes, this work investigated the conversion principles from 3-D style to 2-D patterns considering the theory, mathematical model and conversion process. Conversion methods of different types of garments from 3-D style to 2-D patterns were considered based on double-layer structure, three-layer structure and four-layer structure. Taking five typical styles as examples, the 2-D pattern design and knitting practice were carried out using the SDS-ONE APEX3 system and a four-bed computerized flat knitting machine. The results show that the front and back pieces of the 2-D patterns of the garments with double-layer structure are determined by the side seam and the centerline respectively depending on whether the width of the front and back pieces of 3-D style are equal or not. The 2-D pattern of the garments with three-layer structure are to be determined by dividing in the back centerline or armholes, or unfolding on the side seam and placket based on whether the 3-D style contains sleeves. The connecting position of the inner and outer layers of the garments with the four-layer structure should be located at the collar, waist and other special parts.

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    Rapid quantitative detection of silk grafting ratio based on near infrared spectroscopy
    WANG Rui, SI Yinsong, LU Haohao, GAO Shuang, FU Yaqin
    Journal of Textile Research    2022, 43 (11): 29-34.   DOI: 10.13475/j.fzxb.20210800106
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    The grafting ratio of silk after chemical graft weight gaining treatment is difficult to measure directly, and the existing thermogravimetric analysis method is time-consuming and not suitable for rapid mass detection. In order to solve these problems, a rapid detection method by using near infrared spectroscopy (NIRS) was proposed. Based on NIRS combined with stoichiometry software, the partial least squares was selected as a correction method to establish prediction model of grafting ratio of methylacrylamide grafted silk. The model was optimized from three aspects of spectral pretreatment, modeling bands, and the optimal numbers of principal factor. The internal prediction accuracy of the established model is 91.03%. 19 samples not involved in the modeling were used for the robustness verification,and paired t-test of predicted and reference values showed that at a given significant level α=0.05, there was no significant difference between the results obtained from model prediction and weighing method. Results show that the NIRS technique can provide a rapid and effective method for the quantitative detection of silk grafting ratio.

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    Construction of flexible electronic fabric and its pressure sensing performance
    LI Ganghua, WANG Hang, SHI Baohui, QU Lijun, TIAN Mingwei
    Journal of Textile Research    2023, 44 (02): 96-102.   DOI: 10.13475/j.fzxb.20220104307
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    Objective With the development of artificial intelligence, wearable technology has become a research hotspot, driving the rapid development of all types of sensors. Sensors used in wearable devices should not only have sensitive and stable sensing performance, but should also have excellent flexibility, air permeability, and integration with textiles. Polymer based flexible pressure sensors have significant advantages in flexibility and integration with textiles, and have been developed rapidly. However, most of these sensors are thin films or gel shaped, which seriously affects their breathability and wearing comfort.
    Method Aiming at the problems of poor air permeability, poor moisture permeability and low wearing comfort of film-based and gel-based flexible sensors, a preparation strategy of all-textile-based flexible electronic fabrics based on piezoresistive effect was proposed. A structural model was constructed based on the electrode layer of 1+1 rib conductive fabric and the middle conductive layer of MXene modified cotton fabric (as shown in Fig. 1-3). The flexible electronic fabric with sandwich structure was formed by sewing and compounding various functional layers, and its wearing comfort and sensing performance were studied. Furthermore, its potential for industrial production in the future was expounded.
    Results The sensitivity of the flexible electronic fabric in the low pressure range (0-3 kPa) is about 0.409 5 kPa-1 (as shown in Fig. 4), which is caused by the working mechanism of the piezoresistive flexible sensor. A 2 g weight can make resistance change rate of the flexible electronic fabric exceed 3% (as shown in Fig. 6), which is mainly due to the excellent mechanical properties of the 1+1 ribbed conductive fabric. This enables the flexible electronic fabric to achieve large deformation under small external forces, resulting in rapid changes in resistance values to achieve excellent responsiveness. In addition, the MXene modification of cotton fabrics also gives the flexible electronic fabric a lower minimum pressure detection limit and better low-pressure monitoring performance. The response time of the flexible electronic fabric is less than 50 ms as Fig. 5 shows, sufficient for human motion signal monitoring. The stable resistance changes were maintained after 8 000 pressure cycles, indicating that the flexible electronic fabric maintains good resilience and conductive material wear resis-tance(Fig. 8). In addition, thanks to the full textile configuration of the flexible electronic fabric, it has better air permeability of 270.49 mm/s and moisture permeability of 3 420 g/(m2·24 h), representing better comfort. The flexible electronic fabric can realize the dynamic monitoring of the object, and it is convenient to predict the size and weight of the object qualitatively according to the image size and color depth as illustrated in Fig. 11. The flexible electronic fabric has excellent recognition ability for human body dynamic signals (as shown in Fig.12).
    Conclusion This paper introduces a flexible electronic fabric with piezoresistive effect, which is composed of 1+1 ribbed conductive fabric and MXene modified cotton fabric. It has high sensitivity, fast response and excellent cycle durability. It is able to sense, record and distinguish the pressure of human movement, and achieve dynamic monitoring. On the basis of meeting the sensing requirements, the composition of the whole fabric can meet the needs of thermal-moist comfort and contact comfort of the human body. It has the potential to achieve large-scale industrial production due to its easy preparation process and stable performance, and has broad application prospects in the fields of sports training, medical care and military protection. In the future, the accuracy, sustainability, interactivity and data analysis and feedback of intelligent textiles need be further studied to meet the needs of the end-users with improved behavior.

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    Effect of Lyocell fiber structure on its fibrillation at high speed spinning process
    LI Ting, LI Wenrui, ZHANG Chenxi, CHI Kedong, ZHANG Mingming, LIU Haihui, HUANG Qing
    Journal of Textile Research    2023, 44 (02): 11-18.   DOI: 10.13475/j.fzxb.20211001008
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    Objective The research on the relationship between the condensed structure and the degree of fibrillation of Lyocell fiber at a higher spinning speed is relatively scarce. Selecting appropriate preparation conditions to change the condensed structure of fiber and regulate the degree of fibrillation can ease the main problems that restrict the industrial promotion and scale applications of Lyocell fiber. This research studied the influence of different preparation conditions on the condensed structure of Lyocell fiber and the degree of fibrillation, further established the relationship, which was then used to control the degree of fibrillation at high spinning speed.
    Method In order to explore the relationship between the condensed structure and the degree of fibrillation of Lyocell fiber at high spinning speed, the fibers were spun with different N-methylmorpholine-N-oxide (NMMO) mass fractions, spinning speeds and blowing speeds. The degree of fibrillation was regulated by adjusting the structure. Using X-ray diffraction, wet friction tester and polarized microscope, the effects of NMMO concentration, spinning speed and blowing speed on the condensed structure and the degree of fibrillation were explored.
    Results The condensed structure and fibrillation behavior of the fibers prepared under different conditions are obviously different. Increasing the concentration of the NMMO to a certain extent optimizes the fiber structure, leading to significant increase in the degree of orientation and transverse crystallite size as shown in Tab. 1, and in the degree of fibrillation of the fiber as illustrated in Fig. 2-3. The fiber with low crystal orientation and small crystal size has better antigen fibrillation properties. The coagulation bath with lower NMMO mass fraction is more suitable to prepare low fibrillation Lyocell fiber at high spinning speed. As the spinning speed increases, the crystallinity and the grain size of the fiber increases slightly as suggested in Tab. 2. However, the amorphous region is further oriented and the degree of fibrillation also increases(Fig. 4 and 5). To a certain extent, reducing the spinning speed can reduce the fibrillation of the fiber. Adjusting the air blowing speed has a significant impact on the structure of fiber as shown in Fig. 6, especially on the transverse grain size as shown in Tab. 3, which can control the degree of fibrillation as Fig. 7 reveals. In a certain range, the lower the blowing speed, the less the crystal orientation and the smaller the grain size, the more conducive to reducing the fiber fibrillation. Too low the blowing speed affects the forming of the fiber and the spinning stability.
    Conclusion The condensed structure of Lyocell fiber directly affects the degree of fibrillation. The antigen fibrillation properties of the fiber prepared at high spinning speed is better in having low crystallization, low orientation and small crystallite size. To a certain extent, reducing the concentration of NMMO, spinning speed and blowing speed can reduce the degree of fibrillation. By comprehensively changing the degree of orienta-tion (especially the orientation of amorphous region) and the transverse grain size, the regulation of fibrillation is more obvious. Adjusting the concentration of NMMO is an easier way, among the above factors, to control the fibrillation behavior at high spinning speed. The Lyocell fiber prepared under mild spinning conditions demonstrates better antigenic fibrillation properties.

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    Property characterization and comparative analysis of Lyocell fibers
    HUANG Wei, ZHANG Jiayu, ZHANG Dong, CHENG Chunzu, LI Ting, WU Wei
    Journal of Textile Research    2023, 44 (03): 42-48.   DOI: 10.13475/j.fzxb.20211006107
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    Objective A varity of Lyocell fibers in the market are different in the product quality and spinnability. In order to understand the performance and quality differences of different Lyocell fibers and the analysis of the causes, this research systematically studied the differences of Lyocell fibers in terms of morphological structure, mechanical properties, wear properties, crystallinity, orientation and filament ratio, and analyzed the reasons for the differences. This paper provided suggestions for the subsequent improvement and development direction of domestic Lyocell fibers.

    Method Lyocell fibers from 9 different manufacturers were selected for characterization and comparative analysis on the apparent morphology, mechanical properties, frictional properties, crystallinity, orientation and filament ratio. Due to the differences in the process route and post-treatment technology, the quality of domestic Lyocell fibers has a certain gap compared with Lyocell fibers prepared by major international manufacturers. The characterization instruments used in this research includes SEM,XRD,microscope,fiber wet tribometer and fiber strength tester.

    Results Except for domestic Lyocell fibers, filament cross sections are approximately circular with certain defects and creases on the surface and uneven fiber diameter thickness (Fig.2). The 1# and 3# fibers have a small amount of hollow structure, and the 7#fibers have a large amount of hollow structure. The mechanical properties of all Lyocell fibers from different manufacturers have little difference in dry breaking strength ranging from 3.6 to 4.0 cN/dtex, elongation at break ranging from 7% to 10%, and initial elastic modulus ranging from 60 to 70 cN/dtex (Tab.3). The polymerization degree of the 1# fiber is low (Tab.3). When the capacity of the spinneret component is the same, the cellulose concentration in the spinning stock solution of the 1# fiber is higher, which is more conducive to the increase of production line output and reduce the fiber production cost. The rotation time of friction axis of 1# Lyocell fiber is 8.76 s. The rotation time of friction of domestic Lyocell fiber is short and the degree of fibrillation is relatively high (Tab.4). There is no significant difference in the major diffraction peaks of all Lyocell fibers, and the diffraction peaks of 1# and 2# fibers are significantly lower than those of other fibers (Fig.3). Most of the domestic Lyocell fibers have (040) crystal planes near 2θ of 35.5°, indicating that there are a few quasicrystals in amorphous regions in the fibers. The crystallinity of domestic Lyocell fibers is higher than that of foreign countries on the whole, and the orientation of Lyocell fibers of different enterprises has little difference (Tab.5).

    Conclusion The morphological structure, degree of polymerization, mechanical properties, wear properties, crystallinity, orientation and filament ratio of Lyocell fibers from sampling suppliers were characterized and compared, and the following conclusions were obtained. The Lyocell fiber prepared by major international manufacturers seems to have regular and smooth appearance and regular round cross section, with wet wear loss of 8.76 s, crystallinity of 78.8%, low degree of fibrination, low filament ratio (2.591%), fiber breaking strength of 3.91 cN/dtex, elongation at break of 9.79%. With high yarn strength and excellent fiber quality, Lyocell fiber downstream manufacturers have a high degree of recognition. Due to the difference in processing route and post-treatment technology, the quality of domestic Lyocell fiber is better than that of foreign Lyocell fiber. Domestic manufacturers should continue to optimize the fiber microstructure, gloss, spinnability and brand promotion to further improve the market share of domestic Lyocell fiber. In the future, the domestic manufacturers should continue to optimize the micro-morphology, filament ratio, gloss, spinnability and brand promotion, so as to further improve the market share of domestic Lyocell fiber.

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    Cross-domain generation for transferring hand-drawn sketches to garment images
    CHEN Jia, YANG Congcong, LIU Junping, HE Ruhan, LIANG Jinxing
    Journal of Textile Research    2023, 44 (01): 171-178.   DOI: 10.13475/j.fzxb.20211104908
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    Objective Garment image synthesis is an important part of the garment design and manufacturing process, which uses artificial intelligence technology to automatically generate realistic garment images. Garment design relies heavily on the subjective will of the designer, which often needs to be manually achieved by designers. However, this process is time-consuming and quite inefficient. In the context of artificial intelligence, garment image synthesis can significantly improve efficiency by automatically generating garment images. In addition, it has a wide range of applications in virtual try-on, fashion image manipulation and fashion presentation. Therefore, garment image synthesis has received a lot of attention.
    Method The garment sketch was guided to automatically generate the corresponding garment image by entering the garment attributes. A garment image generation method based on hand-drawn sketches was proposed, namely AGGAN. Generative adversarial networks with attention mechanism was adopted to learn garment sketches and garment image data to obtain AdaIN parameters after One-hot encoding of garment attributes through the attribute incorporation module, which are incorporated into the model, and the model was trained to learn the correspondence between garment images and their visual attributes, thus can generate corresponding garment images under the guidance of given garment attributes.
    Results AGGAN was qualitatively compared with some existing image generation methods (Fig.2). By comparing with all baselines, the AGGAN proposed not only generates garment images with multiple colors, but also generates images closer to the real situation in terms of visual effects. In addition, IS (inception score), FID (fréchet inception distance), and MOS (mean opinion score) was useds for further quantitatively evaluating the model. The IS value of the garment images generated by the method prosposed is 1.253 (Tab.1), which is 13.8% higher than CycleGAN (cycle-consistent generative adversarial networks ) value, and higher than the values from using other methods. The FID value is 139.634, which is 26.2% lower than CycleGAN, and lower than other methods. In addition to the above two evaluation methods, MOS was adopted to evaluate the quality of garment images generated by each method, the MOS score obtained by the method prosposed is 4.352, which is higher than other image generation methods. In order to control the generation of garment images more flexibly, experiments was conducted on attribute-guided garment image synthesis. The garment sketch was controlled by garment attributes to synthesize the corresponding garment image, and the generated garment image has obvious changes in the sleeve length part, which does not seem to be particularly incongruous (Fig.3). The effect of the color attribute on the generated garment images was also explored. Several common color attributes was chosen in the experiments, and it can be seen that AGGAN can generated almost any corresponding color and high-fidelity garment images under the control of color attributes (Fig.4). Texture is also the most intuitive and the main visual feature of the garment image, and several texture attributes was selected in the experiments (Fig.5). From the figure it can be seen that the generation results are more obvious, basically the required texture can be generated, although further improvement is necessary in terms of realism.
    Conclusion The research constructed a garment image generation model based on hand-drawn sketches through the attribute incorporation module, attention mechanism and CycleGAN. Combining the advantages of generative adversarial networks and conditional image generation methods, it took garment attributes as conditions to improve the controllability of the garment image generation process, which helps garment designers to achieve automated garment image synthesis. After a series of experiments, the feasibility and effectiveness of the text method were proved. The method proposed provides new ideas for computer-aided garment design. Some improvements should to be made, for example, the generated garment images cannot generate texture attributes effectively, and there are fewer garment attributes studied.

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    Shirt pattern generating method based on 3-D human scanning model
    XIAO Boxiang, LIU Zhengdong, GUO Yucheng, WANG Yuanxia
    Journal of Textile Research    2022, 43 (12): 151-159.   DOI: 10.13475/j.fzxb.20211003609
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    Aiming at uncontrollable matching error between automatically generated pattern and body shape in shirt customization, an automatic generating method based on 3-D human body scanning model is proposed. The personalized 3-D human model was obtained by scanning the target human body, and the personalized body feature points were extracted on the 3-D human model by analyzing the geometric characteristics of the cross-section curves of the model. A standard 3-D basic model of a shirt was constructed by using the standard mannequin for garment pattern making, and as-rigid-as possible (ARAP) deformation algorithm was used to create the deformation of the standard 3-D basic model with the personalized body feature points as constraints. Finally, using a 3-D model flattening algorithm based on the mass-spring system, the corresponding 2-D pattern was generated according to the deformed 3-D clothing models, and offsets of the edge lines of the pattern verified by experiments were considered in generating the final personalized shirt pattern that adapts to the target body shape. The experimental results show that this method can generate shirt pattern with good fitting. Based on the digital model and automatic processing algorithm, automatic generation of shirt pattern can be achieved that ensures the accuracy and improves the efficiency of personalized pattern making. The research outcome provides a technical solution for garment intelligent manufacturing.

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    Preparation and charging characteristics analysis of hydro charging polypropylene melt-blown nonwovens
    WU Yanjin, WANG Jiang, WANG Hong
    Journal of Textile Research    2022, 43 (12): 29-34.   DOI: 10.13475/j.fzxb.20210604006
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    In order to study the charged characteristics of water electret melt-blown nonwovens, the hydro charging polypropylene melt-blown nonwoven material was prepared. The influence of water conductivity and drying temperature on the filtration performance of samples was investigated. Atomic force microscope, electrostatic potential tester and thermal stimulation discharge instrument were used to analyze the charging characteristics of the hydro charging melt-blown nonwovens. The synergistic effect of corona discharge and hydro charging was studied as well. The results show that the smaller the conductivity of the water used for the hydro charging, the higher the filtration efficiency of the obtained sample. The drying temperature did not affect the physical and filtration performance of obtained samples. After hydro charging, the potential charge of the melt-blown nonwovens increased significantly with random positive and negative distribution. The surface electrostatic potential is the result of overlapping of the electrostatic potential of each layer of the web. It is speculated that electron transfer and ion transfer occur due to frictions between the positive, negative or neutral water droplets and the fiber, resulting in the high static potential of melt-blown nonwovens.

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    Electromagnetic interference shielding properties of composites reinforced with glass fiber/carbon fiber fabrics
    CAI Jie, WANG Liang, FU Hongjun, ZHONG Zhili
    Journal of Textile Research    2023, 44 (02): 111-117.   DOI: 10.13475/j.fzxb.20220808907
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    Objective The electromagnetic (EM) wave pollution and its secondary reflection bring great threat to human health and to information security. To reduce the secondary reflection pollution of carbon fiber fabric composites, enhancing the impedance matching of carbon fiber fabric is a feasible method.
    Method Glass fiber has low dielectric properties; the impedance matching of carbon fiber fabric could be improved by using glass fiber to regulate the fabric structure of the carbon fiber fabric. In this work, five different fabric structures of glass fiber/carbon fiber (G/C) fabric were designed and were compounded with waterborne polyurethane. The morphology, electromagnetic interference (EMI) shielding, dielectric and photothermal conversion properties of glass fiber/carbon fiber composites were characterized by an ultra-depth of field microscope, vector network analyzer, simulated solar xenon lamp light source system and infrared thermal imager.
    Results Glass fiber and carbon fiber interweave with each other to form the G/C fabrics structure which was arranged smoothly as illustrated in Fig. 1. The EMI shielding efficiency (SE) of the five G/C fabric composites showed effective EMI shielding. Their average EMI SE was greater than 20.0 dB in the X band (8.2-12.4 GHz) as can be seen in Fig. 3(a). The EMI total shielding efficiency(SET) curves of C fabric (its weft yarns are all carbon fiber) composites was relatively stable, with its SET being 33.4 dB at 9.6 GHz(Fig. 2(a)). The SET curves of G/C fabrics composites decreased firstly and then increased with the increasing frequency within X band after the introduction of glass fiber. The EMI SE value of G2C1 fabric (glass and carbon yarns were woven into the fabric alternately as weft) composite was up to 38.7 dB at 12.1 GHz, as shown in Fig. 2(a). The power coefficients values of absorptivity of G/C fabric composites increased by adding glass fiber. The structural changes in G/C fabric composites effectively regulate various dielectric polarization relaxation mechanisms (Fig. 5), which indicated that the use of G/C fabric structure could improve the impedance matching with the EM wave and reduce the second reflection. The surface temperature of G/C fabric composites responds rapidly under simulated solar xenon lamp light source as shown in Fig. 6. The surface temperature of G/C fabric composites gradually reached equilibrium after rapidly increasing under 2 kW/m2 light intensity and decreased rapidly when the light source was turned off at 300 s and this was demonstrated in Fig. 6(a). With the increase of glass fiber content, their surface equilibrium temperature was decreased, which is consistent with the results of the SET. The fabric structure of G1C1 fabric composite was clear, indicating its rapid response to the light. The equilibrium temperature of G1C1, as shown in Fig. 6(a), reached 71.8 ℃ at 300 s under 2 kW/m2 light intensity. In addition, the time-temperature curves of G1C1 fabric composite under different light intensities (1,1.5,2 kW/m2) showed that the equilibrium temperature (average temperature from 200 s to 300 s) |ΔT1|,|ΔT2| and |ΔT3| were 8.0, 20.6 and 28.6 ℃, respectively. It is indicated that G/C fabric composites have significant differences in response to different light intensities. Light is also a type of electromagnetic wave. It can be inferred that G/C fabric composite material can quickly convert the energy of electromagnetic wave into joule heat dissipation to achieve excellent electromagnetic shielding performance.
    Conclusion In this work, five G/C fabric composites were fabricated, each possessing efficient EMI shielding and photothermal conversion properties. The dielectric properties of G/C fabric composites were adjustable by structural parameters of G/C fabrics, and the research results demonstrated that such composites could effectively regulate various dielectric polarization relaxation mechanisms. The impedance matching performance of G/C fabric composites increased to match that of the electromagnetic waves and the secondary reflection of the EM wave was reduced. The method of designing fabric structure has great application potential in EMI shielding materials.

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    Preparation of high melt index polylactic acid masterbatch and spinnability of its meltblown materials
    ZHANG Yujing, CHEN Lianjie, ZHANG Sidong, ZHANG Qiang, HUANG Ruijie, YE Xiangyu, WANG Lunhe, XUAN Xiaoya, YU Bin, ZHU Feichao
    Journal of Textile Research    2023, 44 (02): 55-62.   DOI: 10.13475/j.fzxb.20220808108
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    Objective Meltblown polymer raw materials often require a relatively high melt index (MI), due to the fact that the polymer melt is extruded from the spinneret hole and then immediately subjected to high temperature and high speed airflow for rapid fiber formation. The melt flow must match its fiber formation speed, too high and too low MI will lead to the formation of melt droplets, seriously affecting the fiber formation process. In order to investigate the effect of different high melt index of polylactic acid (PLA) masterbatches on their meltblown spinnability, the preparation of PLA meltblown nonwoven materials for overall performance improvement was investigated.
    Method PLA masterbatches with melt indexes of 200, 400, 600, 1 000 and 1 400 g/(10 min) were designed and prepared by catalytic degradation method using spinning grade PLA as raw material, and their capillary rheological properties, molecular weight and its distribution, thermal-crystallization properties and thermal stability were investigated. Further, PLA meltblown materials with different melt indexes were prepared and their morphological structure, fiber diameter and mechanical properties were investigated.
    Results The melt of PLA meltblown masterbatch is typically "tangential thinning", which is characterized by a decrease in shear viscosity with increasing shear rate. The lower the melt index, the more significant the change in shear viscosity with shear rate, as shown in Fig. 2. No significant differences were found in glass transition temperature and melting point for PLA masterbatches with different melt indexes, and a significant cold crystallization peak appeared in the secondary temperature rise curves for MI=600,1 000 and 1 400 g/(10 min), as is shown in Fig. 4 and Tab. 2. It was also found that the crystallinity of the melt decreases as the MI increases. The higher the MI, the lower the molecular weight and the wider the molecular weight distribution (as shown in Fig. 3 and Tab. 1), which manifests itself in lower mechanical properties. The meltblown fiber with MI=400 and 600 g/(10 min) demonstrates the best uniformity and satisfactory mechanical properties, and the most fiber diameter around between 1 and 4 μm, as shown in Fig. 6-7.
    Conclusion In recent years, most of the domestic research on PLA has focused on the modification and functional finishing of this raw material, but the research on the meltblown spinnability of PLA masterbatches with high melt index and their influence on the performance of meltblown materials have not yet seen any systematic research. The research on meltblown spinnability of high melt index PLA masterbatches and its effect on the performance of meltblown materials have not been reported systematically. This study provides a theoretical basis and application guidance for the selection of high-quality PLA meltblown raw materials and the evaluation of their performance.

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    Personalized clothing matching recommendation based on multi-modal fusion
    LIU Junping, ZHANG Fuhong, HU Xinrong, PENG Tao, LI Li, ZHU Qiang, ZHANG Junjie
    Journal of Textile Research    2023, 44 (03): 176-186.   DOI: 10.13475/j.fzxb.20211106611
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    Objective In the context of fast fashion, most consumers do not have the keen insight of professional designers on fashion clothing matching, which leads to their capability of quickly selecting a set of appropriate, harmonious and suitable clothing from a large number of clothing. In order to better improve users' online shopping experience and help them accurately express their unique personality characteristics, professional identity, status and other image positioning to the outside world, this paper aims to achieve high-precision recommendation by improving the clothing matching degree, so as to meet the huge demand of consumers for personalized clothing matching recommendation.

    Method By studying the highly nonlinear complex attribute interaction from clothing color to category, and based on the quantitative standard of matching degree of clothing matching, an embedded model of the potential feature representation space of an item was built. By building a matrix decomposition framework model that integrates multimodal information, the shortcomings of existing multimodal feature fusion algorithms were further analyzed, and the clothing style preferences of different users were depicted. Through feature extraction, multimodal feature fusion match degree was calculated and other operations were carried out to establish personalized clothing matching scheme.

    Results PCMF (personalized clothing matching recommendation based on multi-modal fusion) with some conventional clothing matching methods were qualitatively compared. Compared with all baselines, the clothing matching degree calculated by this model reached 0.81, which is 1.25% higher than the AUC (area under curve) value of conventional methods (Tab.2). It is confirmed that the transposition fusion method of text features and visual features used in PCMF improves the correlation between features, making the presentation of individual style more accurate. In order to compare the difference of contribution of different modal information to the matching degree of PCMF modeled clothing, experiments under three different modal combinations were conducted, i.e. PCMF-T (only exploring the text information of items), PCMF-V (only exploring the visual information of items), and PCMF-TV (exploring the visual and text information of items) (Tab.3). The AUC value of PCMF-T reached 0.775, higher than that of PCMF-V (0.763), indicating that the text information of the piece can more succinctly summarize the key features of the piece, such as patterns, materials and brands. PCMF-TV shows better performance than PCMF-T and PCMF-V, which indicates the necessity of combining multi-modal information of items, and verifies the effectiveness of adding user factors to the general clothing matching modeling to make personalized clothing matching recommendation. In order to effectively evaluate the practical application of the PCMF model, the PCMF model was deployed in the complementary item retrieval task (Fig.5). It is demonstrated that the PCMF model can complete the personalized clothing matching recommendation task according to the user's preferences. In addition, the MRR (mean reciprocal rank) measurement method was used as the evaluation index to further evaluate the model. PCMF performs better than other models regardless of the number of clothing candidates (Fig.6).

    Conclusion Through the combination of IGCM (item-item general clothing match modeling) and UPCM (user-item personalized clothing match modeling), a personalized clothing matching recommendation model based on multi-modal fusion is constructed, which facilitates high-precision personalized clothing matching recommendation. Specifically, the purpose is to match a lower garment that not only has a good match with a given user's top, but also meets the user's taste. In general, the research results show the necessity and effectiveness of combining visual and text modal information and introducing user factors in personalized clothing matching recommendation and the practical application value of PCMF in real scenes is verified. In the future, the clothing matching recommendation problem of two examples will be transformed into a multi-instance learning problem to provide users with personalized package recommendation including shoes and accessories.

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    New measurement method for fabric multi-directional bending performance
    LIU Chengxia, ZHANG Yaqi
    Journal of Textile Research    2022, 43 (10): 53-57.   DOI: 10.13475/j.fzxb.20210807605
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    Under the widely used testing method for fabric bending performance, only one result for one direction can be obtained by using one fabric. To investigate a testing method that can characterize fabric multi-directional bending performance simultaneously, 20 common fabrics were chosen and tested with the conventional method to obtain the bending length in the directions of 0°、90°、45°和135° by cutting the fabric sample into stripes along these four directions for testing. Correlation analysis was conducted between projection length and projection area with bending length. It was concluded that both the projection length and projection area have good correlation with bending length of the conventional method, with the coefficient about 0.95, which proves the new method can be used to characterize the bending properties of 0°、90°、45° and 135°. Two reading can be obtained in each direction, and therefore, it is more efficient and accurate than the conventional method. Besides, it can visualize fabric anisotropy in bending performance and display the testing stability of bending in one direction.

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    Balance optimization of clothing mass customization production line based on genetic algorithm
    CHEN Sha, XIU Yi, LI Xuefei
    Journal of Textile Research    2022, 43 (12): 144-150.   DOI: 10.13475/j.fzxb.20211100208
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    In order to solve the problems of long product online time, unbalanced tempo, and high production cost in the production process of mass-customized mixed assembly line, the research reported in this paper first analyzed the characteristics and problems of the complex production line of clothing mass customization, and constructed a hybrid production line balance optimization model with multi-subgroup management, multi-objective optimization and clothing single-piece customization. The research used the matrix principle to constrain the coding of the process, and established a decoding algorithm for station conversion. As a result, production balance of the entire mixed pipeline was achieved using the designed algorithms for roulette selection, two-point crossover and single-point mutation, and multi-objective fitness function. Mass customization production line of suits was taken as an example to demonstrate the use of MatLab technology for programming. The results show that the highest preparation efficiency of all sub-production lines can reach 93.93%, the average preparation efficiency of the total production line is 85.77%, which meets the requirements of the process planning set by the collaborating enterprise. It is indicated that the model established in this research can effectively solve the production balance problem of the mass customization production line.

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    Preparation and filtration properties of polyethylene trifluoroethylene melt-blown nonwovens
    YANG Xiaodong, YU Bin, SUN Hui, ZHU Feichao, LIU Peng
    Journal of Textile Research    2023, 44 (02): 19-26.   DOI: 10.13475/j.fzxb.20220811008
    Abstract181)   HTML26)    PDF(pc) (4174KB)(84)       Save

    Objective In order to prepare high temperature resistant melt-blown filter materials to deal with the pollution of high temperature industrial dust, the thermal properties, dynamic thermomechanical properties, rheological properties and morphology of polyethylene trifluoroethylene (ECTFE) masterbatch were studied at first, and then the ECTFE melt-blown nonwovens were to be prepared by selecting appropriate process parameters. So far, there are few studies on ECTFE melt-blown nonwovens for air filtration.
    Method The properties and structures of ECTFE masterbatch were determined by differential scanning calorimeter, dynamic thermo mechanical analyzer, thermogravimetric analyzer and melt flow meter. The ECTFE melt-blown nonwovens were then successfully prepared according to these studies on ECTFE masterbatch. The surface morphologies and pore size distribution of ECTFE melt-blown nonwovens were scrutinized by scanning electron microscope and pore size meter. The ECTFE melt-blown nonwovens was preheated at different tempera-tures (150, 170, 190, 210 and 220 ℃) using a muffle furnace. After that, the filtration efficiency and tensile properties of ECTFE melt-blown nonwovens was calculated by the dust particle detector and universal tensile tester.
    Results The results show that with the increase of heating rate, the melting peak(Tp) of ECTFE masterbatch shifted to the right, and Tp was enhanced from 235.02 to 239.21 ℃, and the width of half peak increased(Fig. 3). The glass transition temperature of ECTFE masterbatch was found to be about 86.2 ℃(Fig. 4). The decomposition temperatures at initial and 5% weight lost were 300 and 372 ℃, respectively. It is obvious that for ECTFE masterbatch the temperature of the thermogravimetric zone was obviously higher than that of the melting process, which ensures the smooth process of ECTFE melt-blown nonwovens. When the test temperature increased from 250 to 290 ℃, the melt flow index elevated from 180 g/(10 min) to 376 g/(10 min), indicating that the melt fluidity of ECTFE masterbatch became better with the increasing of the temperature(Fig. 6(a)). The diameter of the fibers in ECTFE melt-blown nonwovens ranged from 4 to 12 μm, and its average diameter was about 7.12 μm. Additionally, the pore size of ECTFE melt-blown nonwovens was mainly in the range from 45 to 55 μm(as shown in Fig. 7). The filtration efficiency of ECTFE melt-blown nonwovens for PM10 was maintained at 99.96% after it was preheated at temperatures of 150~210 ℃. Although the filtration efficiency of ECTFE melt-blown nonwovens for PM2.5 and PM5 decreased slightly with the increasing of preheated temperatures, it still exceeded 55.16% and 72.93%, respectively(Fig. 8).
    Conclusion The glass transition temperature and melting peak of ECTFE masterbatch were about 86.20 and 235.02 ℃, respectively. Its complex viscosity decreased when increasing the shear rate and the ECTFE was categorized as a "pseudoplastic fluid". Besides, ECTFE masterbatch has excellent thermal stability at constant temperatures of 260, 270 and 280 ℃. ECTFE melt-blown nonwovens can be successfully fabricated under the conditions of heating temperature 260 ℃, hot air temperature 260 ℃, airway pressure 0.2 MPa, melt-blown pressure 0.5 MPa, acceptance distance 13 cm and translation speed 0.1 mm/s. The fibers in the ECTFE melt-blown nonwovens web were randomly interleaved and wound, and ensures that the ECTFE melt-blown nonwovens with high filtration efficiency. Therefore, it is believed that ECTFE melt-blown nonwoven should be an ideal filter material for high temperature resistant air filtration.

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