中文摘要本论文通过种子乳液聚合方法,制备核/壳结构硅橡胶粒子。在制备 PSi 种子乳液过程中通过称量法测量单体转化率,研究了催化剂、乳化剂和反应温度对有机硅乳液聚合反应动力学的影响。实验结果表明:提高反应温度、增加浓硫酸和SDBS的溶度有利于加快反应速率,提高单体转化率。该反应的聚合速率与浓硫酸浓度0.54次方、SDBS浓度 0.49 次方成正比,该反应的表观活化能为 39.5164KJ/mol。得到 PSi 种子乳液后,后续聚合采用 BMA 作为单体。在适宜的聚合条件下PSi 种子乳液与 BMA 接枝共聚,从而得到具有核/壳结构的 PSi/PBMA复合乳液。复合乳液进过破乳,过滤和烘干后得到核/壳结构硅橡胶粒子。研究 PSi/PBMA复合乳液的稳定性并利用红外光谱仪、热重分析仪和透射电子显微镜对产物进行表征。结果表明:粒子呈规整球形,具有明显的核壳结构;SDBS 的用量对复合乳液的稳定性有很大的影响。粒子兼具硅橡胶和聚丙烯酸酯的优良性能,有望在生物材料、涂料、粘合剂和增韧剂方面获得应用。 6568
关键词 硅橡胶 核/壳结构 接枝共聚物 热性能 反应动力学 稳定性
Title Study on preparation of core-shell silicone rubber particles
Abstract
In this study, the core-shell silicone rubber particles were synthesized by
seeding emulsion polymerization method. The monomer conversion rate was
measured during the preparation of PSi seed emulsion by the gravimetric method.
The influence of concentration of H2SO4 and concentration of emulsifier (SDBS),
reaction temperature on the kinetics of reaction were investigated. The
results showed that the finally monomer conversion and the rate of the
copolymerization was promoted when the reaction temperature raised and the
concentration of catalyst or emulsifier increased. The apparent reaction order
for sulfuric acid and emulsifier was 0.54 and 0.49 respectively. The total
activation energy of the copolymerization was 39.5164 KJ/mol.
After the preparation of PSi seed emulsion, the subsequent polymerization
using BMA as the monomer. Under the suitable polymerization conditions, the
PSi seed emulsion was copolymerized with BMA to form the graft copolymer. We
got the PSi/PBMA core-shell particles by demulsifying, filtering and drying
the PSi/PBMA composite emulsion. The stability of the PSi/PBMA emulsion was
investigated. The structure and performance of core-shell silicone rubber was
confirmed by FT-IR,TEM and thermo gravimetric analysis (TGA).
Keywords silicon rubber core-shell structure graft copolymers thermal
properties reaction kinetics stabilization
目 次
1 绪论 ... 1
1.1 硅橡胶简介及发展现状 . 1
1.2 核/壳结构硅橡胶粒子的发展及现状 .. 2
1.3 核/壳结构硅橡胶的制备 4
1.4 课题研究的主要内容 .. 10
1.5 课题研究的意义 .. 11
2 有机硅乳液聚合动力学研究 .. 11
2.1 前言 11
2.2 实验部分 11
2.3 实验结果与讨论 .. 14
2.4 本章小结 24
3 核/壳硅橡胶粒子的制备及表征 ... 24
3.1 前言 24
3.2 实验部分 25 核壳结构硅橡胶粒子制备+文献综述:http://www.youerw.com/cailiao/lunwen_4166.html