聚对苯二甲酸乙二醇酯扩链产物的分子结构  

Molecular Structure of Chain-Extended Poly(Ethylene Terephthalate)

作　　者：戴剑峰[1,2] 俞炜[1,2] 周持兴[1,2] 

机构地区：[1]上海交通大学流变学研究所 [2]上海交通大学化学化工学院,上海200240

出　　处：《高分子材料科学与工程》2009年第10期71-73,77,共4页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(50390095)

摘　　要：采用不同含量的四官能团单体均苯四甲酸酐(PMDA)提高聚对苯二甲酸乙二醇酯(PET)的熔体强度,在增加PET分子量的同时,使PET发生支化反应。频率扫描结果表明,扩链反应显著提高了PET的弹性模量和复数黏度;运用傅立叶变换流变学方法对长支链进行表征,根据三次谐波与基频幅值比与应变的幂律关系,发现在中等应变幅值下,扩链产物的幂律指数n均小于2,表明生成了不同支化程度的支链结构。扩链产物的黏度随扩链剂的增加而增加,但是扩链产物的支化度对扩链剂浓度存在最大值。The chain extension of poly（ethylene terephthalate）（PET） with a tetra functional monomer,pyromellitic dianhydride（PMDA）,has been performed by varying the chain-extender amount to improve the melt strength.The reaction can increase the molecular weight of PET,while leading to chain-extension and branching.The results of frequency sweep test show that the chain-extended PET samples exhibit higher storage modulus and higher complex viscosity.Fourier transform rheology was used to characterize the long chain branching.The power index n of the amplitude rate between 3rd harmonic and 1st harmonic（I3/I1） vs.strain amplitude of chain-extended PET samples is smaller than 2,which implies the generation of branched structure.Furthermore,the degree of branching is found to depend on the amount of PMDA,and has a maximum for intermediate amount of addition.

关 键 词：聚对苯二甲酸乙二醇酯 扩链 支化 流变 

分 类 号：TQ323.41[化学工程—合成树脂塑料工业]