关键词: 非织造材料, 生物降解, 降解机制, 降解标准, 聚乳酸

Abstract:

Significance Biodegradable polymer nonwoven fabrics, with their excellent biocompatibility and environmental degradability, are considered a prime example of green and low-carbon textile materials. In the context of growing global environmental awareness, such materials have found widespread application across numerous fields, including healthcare (e.g., surgical gowns, dressings, disinfectant wipes), daily consumer goods (e.g., eco-friendly shopping bags, cleaning cloths), transportation engineering (e.g., interior trim, soundproofing materials), and modern agriculture (e.g., agricultural films, seedling bags, protective coverings). Their core value lies in their ability to absorb and utilise energy and nutrients from the environment, ultimately decomposing into water, carbon dioxide, or methane, as well as biomass, through microbial action, thereby returning to the natural cycle. Compared to traditional petroleum-based plastics, biodegradable non-woven fabrics offer significant advantages, including sustainability, high efficiency, ecological safety, effective degradation of polymers, and an extremely broad range of applications. Therefore, studying their degradation performance, degradation mechanisms, and influencing factors provides support for promoting the widespread application of biodegradable polymer nonwoven materials in the textile industry, thereby fostering the standardisation and sustainable development of the biodegradable polymer nonwoven materials industry.

Progress Research on the degradation behaviour of biodegradable polymer nonwoven materials has shifted from single-factor environmental assessment to the analysis of multi-factor synergistic mechanisms. Focusing on biodegradable materials such as polylactic acid(PLA), polyvinyl alcohol(PVA), polyhydroxyalkanoates(PHA), polycaprolactone(PCL), poly(butylene terephthalate-co-adipate)(PBAT), and poly(butylene terephthalate-co-succinate)(PBST), researchers have prepared nonwoven materials using processes such as spunbonding and meltblowing, systematically revealing their degradation pathways in environments such as soil, compost, and seawater. PLA/PCL degradation relies on ester bond hydrolysis (dominated by lipases), PVA degrades through side-chain oxidation (catalysed by dehydrogenase), while PHA, due to its natural aliphatic structure, is easily directly mineralised by microorganisms. Degradation rates are synergistically regulated by internal and external factors. Internally, low crystallinity (e.g., PHA amorphous regions >70%), linear molecular chains (PVA hydrolysis >88%), and copolymer disorder (PBAT aromatic units <60 mol%) significantly accelerate degradation, and in the external environment, thermophilic temperatures (composting at 58-80 ℃), alkaline pH (PLA degradation rate increased to 96%), rich microbial communities (CO₂ release >350 mg at bacterial suspension concentration of 10⁸ CFU), and non woven processes (electrospun high specific surface area > meltblown > spunbond) are key promoting factors. Recent breakthroughs have focused on the establishment of degradation standard systems. International standards (ISO 14855, ISO 19679) and national standards (GB/T 19277, GB/T 40611) have covered scenarios such as aqueous culture, industrial composting, and marine deposition, with clear core evaluation indicators including biodegradation rate (aerobic environment >90%), disintegration rate (12 weeks > 90%), and ecological toxicity (OECD 208) as core evaluation criteria. However, the absence of household composting standards (only ISO 21701 as a reference) and insufficient marine field verification (field cycles > 2 years) remain bottlenecks for industrialisation. In the future, it will be necessary to integrate process-structure-environment parameter quantitative models to promote the implementation of a closed-loop degradation certification system.

Conclusion and Prospect To significantly enhance the degradation efficiency of biodegradable polymer nonwoven materials, researchers have explored their specific compatibility with different categories of degradative enzymes (such as proteases, lipases, and cellulases) and regulated parameters of the degradation environment such as temperature, humidity, pH value, and microbial community composition. Ideal biodegradable nonwoven materials must not only meet the diverse application requirements of medical, hygiene, agricultural, and packaging sectors but also ensure efficient and controlled return to the natural environment at the end of their lifecycle. Currently, China urgently needs to continuously improve the evaluation and management system for biodegradable materials to scientifically guide the industry in achieving the optimal balance between material performance and environmental friendliness. However, high production costs remain the primary bottleneck constraining large-scale application. Therefore, efficiently separating and extracting low-cost, high-performance biodegradable polymer raw materials from natural resources has become the industry's top priority for breakthroughs. Meanwhile, the degradation rates of existing materials under complex natural conditions remain insufficient, with significant room for improvement. This necessitates the industry actively exploring innovative production processes to achieve efficient and scalable production while simultaneously enhancing product uniformity and overall quality. To this end, researchers need to conduct more in-depth analyses of the microscopic mechanisms of biodegradation in different environments, establish quantitative predictive models linking material structure, degradation kinetics, and environmental factors, and use these as a foundation to collaboratively develop a comprehensive, authoritative, and unified product certification system, scientifically rigorous degradation evaluation standards, and rapid and efficient degradation testing methods covering the entire lifecycle of the materials. Achieving a complete closed-loop management system for biodegradable non woven fabrics from "raw material acquisition-product manufacturing-consumer use-waste degradation-resource regeneration" will truly realise the harmless and resource-efficient disposal of environmental waste.

Key words: nonwoven material, biodegradability, degradation mechanism, degradation standard, polylactic acid