化工学报 ›› 2006, Vol. 57 ›› Issue (1): 197-202.

• 材料科学与工程 • 上一篇    下一篇

乙烯基硅氧烷改性丙烯酸酯乳液聚合的动力学及成核机理分析

张心亚;黄洪;黎永津;沈慧芳;蓝仁华;陈焕钦   

  1. 华南理工大学化工学院化工研究所,广东 广州 510641
  • 出版日期:2006-01-25 发布日期:2006-01-25

Kinetics and nucleation mechanism of acrylate emulsion polymerization modified by vinyl alkoxy silane

ZHANG Xinya;HUANG Hong;LI Yongjin;SHEN Huifang;LAN Renhua;CHEN Huanqin   

  • Online:2006-01-25 Published:2006-01-25

摘要: 用种子乳液聚合法研究了硅氧烷改性丙烯酸酯的乳液聚合,对影响种子乳液聚合动力学的因素进行讨论,并分析了乳液聚合的成核机理.实验结果表明:反应温度、引发剂浓度、乳化剂浓度和有机硅氧烷用量对有机硅改性丙烯酸酯乳液聚合动力学有较大的影响.反应温度越高,引发剂浓度越高、乳化剂浓度越高、有机硅氧烷用量相对较小,乳液聚合反应的转化率越高;此外,体系的pH值在6~8之间时也有利于反应的进行.种子乳液聚合中RP∝[E]0.72RP∝[I]0.56,表观活化能Ea为143.92 kJ•mol-1.种子乳液聚合初期,反应主要是单体液滴成核;进入壳层反应时,反应成核主要是以胶束成核为主.

关键词: 硅氧烷, 丙烯酸酯乳液, 聚合反应动力学, 成核机理

Abstract: The factors which influence polymeric kinetics of acrylate emulsion modified by vinyl alkoxy silane through seed emulsion polymerization were investigated, and the nucleation mechanism of emulsion polymerization was analyzed. The experimental results showed that reaction temperature, initiator concentration, emulsifier concentration and vinyl alkoxy silane amount had great influence on the kinetics of emulsion polymerization.At higher temperature, higher initiator concentration, higher emulsifier concentration and less amount of vinyl alkoxy silane monomer, the conversion rate of emulsion polymerization was higher.Besides, the pH value of the system between six and eight was favorable to emulsion polymerization kinetics.In the seed emulsion polymerization,RP∝[E]0.72RP∝[I]0.56Ea=143.92 kJ•mol-1. At the beginning of the shell reaction, nucleation of emulsion polymerization occurred in monomer droplet,while during core reaction, the nucleation mechanism was “micellar nucleation”.

Key words: 硅氧烷, 丙烯酸酯乳液, 聚合反应动力学, 成核机理