中国塑料 ›› 2010, Vol. 24 ›› Issue (03): 29-33 .DOI: 10.19491/j.issn.1001-9278.2010.03.005

• 材料与性能 • 上一篇    下一篇

L-丙交酯与ε-己内酯共聚物微观结构与热力学性能研究

鲁越 熊左春 张胜蓝 熊成东 陈栋梁   

  1. 中科院成都有机化学研究所 中科院成都有机化学所
  • 收稿日期:2009-10-20 修回日期:2009-11-13 出版日期:2010-03-26 发布日期:2010-03-26

Study on the Microstructure and Thermal Properties of L-lactide and ε-caprolactone Copolymers

Yue LU Zuochun XIONG Shenglan ZHANG Chengdong XIONG Dongliang CHEN   

  • Received:2009-10-20 Revised:2009-11-13 Online:2010-03-26 Published:2010-03-26
  • Contact: Dongliang CHEN

摘要: 以辛酸亚锡作为催化剂催化L-丙交酯(L-LA)和ε-己内酯(ε-CL)的本体开环共聚合。通过改变聚合单体投料比,合成了不同组分的系列共聚物。根据共聚物的核磁共振氢谱(1H-NMR)结果,利用伯努利统计法计算出了共聚物理论和实验嵌段平均长度。结果表明,随着共聚物中己内酰摩尔含量从0.1增加到0.5,共聚物中的双乳酰实验嵌段平均长度(LeLL)从20.0下降到4.2,己内酰实验嵌段平均长度(LeC)从2.4增加到4.2。根据共聚物的差示扫描量热分析的测试数据,考察了共聚物的热力学性能。结果表明,随着共聚物中己内酰摩尔含量的增加,共聚物的熔点(Tm)从161.3 ℃下降到120.5 ℃,熔融焓(△Hm)从31.5 J/g下降到8.0 J/g,玻璃化转变温度(Tg)从51.5 ℃下降到-3.2 ℃。

关键词: L-丙交酯, ε-己内酯, 共聚物, 微观结构, 热力学性能

Abstract: L-lactide(L-LA) and ε-caprolactone(ε-CL) were copolymerized in bulk using stannous octoate as a catalyst. By varying the polymerization monomer feed ratios, copolymers with various compositions can be synthesized. The experimental and theoretical block average sequence lengths based on Bernoullian statistics were calculated from the 1H NMR spectra. With increasing amount of caproyl from 0.1 to 0.5, it is found that the experimental average sequence lengths of the lactidyl units (LeLL) decreased from 20.0 to 4.2, and the experimental average sequence lengths of the caproyl units (LeC) increased from 2.4 to 4.2. The thermal properties of the obtained copolymers were investigated by differential scanning calorimetry (DSC). While the amount of caproyl increased from 0.1 to 0.5, the melting point(Tm) decreased from 161.3℃ to 120.5℃; the heat of melting (△Hm) decreased from 31.5J/g to 8.0J/g; and the glass transition temperature decreased from 51.5℃ to -3.2℃.

Key words: L-lactide, ε-caprolactone, copolymer, microstructure, thermal property