生物可降解PBST纤维的拉伸回弹机理.docVIP

 n 生物可降解 PBST 纤维的拉伸回弹机理# 李发学，罗胜利，俞建勇* （东华大学纺织学院） 5 10 摘要：研究了生物可降解聚对苯二甲酸丁二醇-共-丁二酸丁二醇酯（简称 PBST）纤维的拉 伸及回弹性能，分析了 PBST 纤维的拉伸回弹机理，并与聚对苯二甲酸丁二醇酯（简称 PBT） 纤维做了比较。研究结果表明：与 PBT 纤维相比，由于脂肪族 BS 链段的引入，赋予 PBST 纤维具有较长的线性弹性区，较低的初始模量和较高的断裂伸长率，且 PBST 纤维拉伸曲线 并不是经典的反-S 曲线；在相同条件下，PBST 纤维的拉伸回弹性能优于 PBT 纤维；通过 广角 X 射线衍射（WAXD）分析了 PBST 纤维拉伸过程中的α、β晶型转变，较好地解释 了 PBST 纤维的拉伸回弹机理。 关键词：拉伸性能；拉伸回弹性；弹性机理；晶型转变 中图分类号：TQ 342 15 Stretch elastic recovery mechanism of biodegradable poly(butylene succinate-co-terephthalate)(PBST) fibers LI Faxue, LUO Shengli, YU Jianyong (College of Textile, Donghua University, Shanghai City 201620) 20 25 30 35 40 Abstract: IThe tensile property and stretch elastic property of biodegradable poly(butylene succinate-co-terephthalate)(PBST) fibers were intensively studied, and the stretch elastic recovery mechanism of PBST fibers was analyzed. For comparison, poly(butylene terephthalate) (PBT) fibers were adopted as a comparison sample. The results showed that the combination of soft butylene succinate (BS) unit and hard butylene terephthalate (BT) unit for PBST fibers made contribution to the wider elastic region, lower initial modulus and higher elongation at break than those of PBT fibers. Moreover, the tensile curve of PBST fibers was not the classic anti-S curve. Under the same testing condition, PBST fibers showed better stretch elastic recovery than that of PBT fibers. In addition, PBST fibers were found to undergo crystal form transition from α-form to β-form crystal structure under tension load through the measurement of WAXD, which well explained the stretch elastic mechanism of PBST fibers. Key words: Tensile property; stretch elastic recovery; elastic mechanism; crystal transition 0 引言 纤维的弹性对纺织品的抗折皱性、尺寸稳定性、耐冲击性能和耐疲劳性能等都有着密切 的关系，是评价纤维力学性能的一个重要因素，其大小主要受到纤维结构的影响。纺织弹性 纤维从橡胶弹性体发展而来，向着多样化、功能化的方向发展。纺织弹性纤维主要包括聚氨 酯弹性纤维、聚醚酯弹性纤维、二烯类弹性纤维、聚烯烃弹性纤维、复合聚酯弹性纤维、新 型聚酯弹性纤维（如聚对苯二甲酸丁二醇酯（简称 PBT）纤维、聚对苯二甲酸丙二醇酯（简 称 PTT）纤维）、形状记忆弹性纤维等，这些弹性纤维通过 “软”链段和“硬”链段相结合， 或者是具有易伸长和回复的大分子结构产生弹性，除了具有本征弹性