Abstract: To get an insight into the thermodynamic property of composite fiber, TG and DSC were used to analyze the thermodynamic property of composite fiber, along with the heat-resistance and limiting oxygen index. As the temperature increases, the composite fiber's TG curves appear two weight loss bands, and the main weight loss temperature is about 312°C. The composite fiber's DSC curve appears double melting peaks; the breaking strength of composite fiber drops as the temperature increased to 90 ~ 110 °C.However,when the heating temperature reaches 150 °C, the breaking strength of the composite fiber exhibits 15.1% higher than the original value. Increasing the temperature decreases the breaking elongation of the fiber. The combustion behavior of composite fiber is similar to those of cotton and viscose fibers, and the limiting oxygen index of the composite fiber is 19 - 20 %.

Key words: composite fiber, thermodynamic property, heat resistance, combustion behavior