聚烯烃弹性纤维XLA^TM的结构及其弹性表征

通过扫描电镜（SEM）、红外光谱（FT—IR）、力学试验和差示扫描量热法（DSC）等测试方法表征了聚烯烃弹性纤维XLA^TM的结构和弹性，对比分析了氨纶和XLA州纤维弹性的作用机理。XLA^TM纤维截面为圆矩形，表面较光滑；分子组成中不存在不饱和双键和非烃类物质，化学结构稳定；晶体中存在准六方晶和正交晶系两种晶型，结晶度为30％，比一般聚烯烃类纤维低很多；常温下处于高弹态，熔程较宽，为45～80℃；该纤维初始模量较氨纶高，在伸长率大于130％后拉伸强度比氨纶小；弹性回复率随伸长率的增加呈非线性下降趋势，塑性变形在180S内随回复停顿时间的延长而减小。

The Characterization of Structure & Elastic Properties of Polyolefin Based Elastic Fiber XLATM

The structure and elasticity of polyolefin based elastic fiber XLATM were characterized through SEM, FR-IT and DSC etc. Comparing to polyurethane, elastic mechanism of XLATM fiber was analyzed. It was found that the fiber was round rectangle in cross section and smooth in surface. Unsaturated C=C band and non-hydrocarbons were not present. There were pseudo hexagonal and orthorhombic crystal structures in the material and the crystallinity was 30 % which was lower than that of common polyolefin fibers. XLATM fiber was in high elastic state at ambient temperature and the melting range was from 45 ℃ to 80 ℃. Initial modulus of XLATM fiber was higher than that of polyurethane, while the strength was lower when e-longation was above 130 %. There was a downward trend in non-linear on elastic recovery of XLATMfiber with the increase of elongation and the plastic deformation decreased with extending dwell time after recovery within 180 s.