氧化还原引发体系对多层核壳结构ACR乳液聚合的影响

采用多步乳液聚合方法合成多层核壳结构的ACR树脂。用过硫酸钾/亚硫酸氢钠体系作为氧化/还原引发体系,研究了氧化剂和还原剂用量的不同及氧化还原引发体系的加入方式对ACR的转化率、乳胶粒的粒径和PVC/ACR共混物加工流变性能的影响。实验结果表明:氧化剂和还原剂用量增加后,乳液聚合各个阶段的转化率提高,乳胶粒的粒径变大,明显改善了共混物的加工性能。过量的还原剂起阻聚和缓聚作用,采用分阶段加入氧化还原引发剂有利于提高转化率。

Influence of Redox Initiator on the Emulsion Polymerization of ACR Resin with Multi-layer Core-shell Construction

ACR resin with multi-layer core-shell construction was synthesized by multi-stage emulsion polymerization. By using KPS/SHS redox system as initiator, the effect of various amount of oxidative agent and reductive agent and the doping manner on the conversion rate, the size of latex particles of ACR and the rheological properties in processing of PVC/ACR blends were researched. The results indicate that the size of latex particles and the conversion rate increased with the increasing of oxidant and reductant. It can make the processability of PVC/ACR blends were improved by the redox initiator, the excess reductive agent act as inhibitor or retarder, the conversion rate can increase through step addition of redox initiator.