ASA核-壳乳液聚合物的组成、结构与性能

基于聚合物共混改性原理和增韧机理,设计出ASA三元复合聚合物。研究发现,ASA复合聚合物具有核-壳结构,核与壳之间存在接枝产物,接枝产物的组成为A/S=18.4/81.6(重量比),略低于其乳液恒比组成(A/S=20/80),接枝率随核的交联剂、乳化剂及壳层单体的用量增大而增大。动态粘弹谱(DMS)显示在核的聚合物相中存在壳的聚合物相畴。ASA复合聚合物与其机械共混物具有相同的热稳定性,但具有更好的韧性。其缺口抗冲强度在交联剂为1.0％时出现极大值,并随橡胶粒径和含量的增大而增大,韧性大大高于ABS。

Composition,Structure and Properties of ASA Core-Shell Emulsion Terpolymer

A butyl acrylate-styrene-acrylonitrile (ASA) terpolymer was investigated. It is found that the particles of the terpolymer have a core-shell structure, witha graft copolymer having a composition of acrylonitrile/styrene wt ratio of 18.4/81.6existing in between. The degree of grafting increases with increasing level of the crosslinking agent, emulsifier and monomerM_2]. DMS has shown that there is microdomain of resin phase in the rubber phase. The ASA composite terpolymer has the same heat-resistance as its mechanical blend, but better toughness. Its impact-resistance is maximum at a crosslinking agent concentration of 1％, and it increases with the particle diameter and content of rubber; it is much higher than ABS.