交替张力热处理对聚对苯二甲酸丙二醇酯纤维弹性的提升

Increase of Elasticity of Poly(trimethylene terephthalate) Fiber Through Heat-Treatment with Alternating Tension

采用松弛、张力和交替张力等受力条件在160℃对聚对苯二甲酸丙二醇酯(PTT)纤维进行干热处理并研究纤维弹性的变化。采用红外光谱分析热处理前后PTT纤维构象的变化;采用弹性仪和动态力学热分析仪研究热处理对PTT纤维弹性回复率的影响。结果表明,经交替张力热处理,PTT分子链由构象能较高的g-t-t-g构象转变成构象能较低的t-g-g-t构象,有利于PTT纤维的弹性及其稳定性的提高,以30%定伸长经5次循环拉伸测试后弹性回复率仍达到79%,比未经处理PTT纤维提高了约10%。

Poly(trimethylene terephthalate)(PTT)fibers were heat-treated in relaxation,with tension or with alternating tension at 160℃.The conformation transition of PTT fibers before and after heat-treatment was studied by Fourier transform infrared spectroscopy.The elastic recoveries of PTT fibers before and after treatment were compared by elastic meter and dynamic thermomechanical analyzer.The results show that the higher-energy conformation of trans-conformation converts to the lower-energy conformation of gauche-conformation after alternating tension heat treatment,which increase the elasticity and its stability of the fibers.The elastic recovery of the fiber treated with alternating tension after 5 cyclic drawing at 30%fixed elongation is still 79%,being about 10%higher than that of the untreated PTT fiber.