核壳PBA/PMMA乳液粒径分布规律与壳层聚合研究  

Particle size distribution and shell polymerization of PBA/PMMA core/shell latex

作　　者：杜万里[1] 郭红霞[1] 王群[1] 

机构地区：[1]北京工业大学材料学院,北京100022

出　　处：《现代化工》2007年第z1期249-252,共4页Modern Chemical Industry

基　　金：国家"863"计划(2002AA245161);国家自然科学基金(30371129)资助

摘　　要：通过半连续饥饿态法合成了核壳型PBA/PMMA乳液,并利用激光粒度仪时实监控壳层聚合阶段粒子粒径变化,结合理论数学计算模型,研究了壳层单体加料速度与补加乳化剂的量对平均数均粒径及其分布与总粒子数的影响。理论计算乳液中的总粒子数的变化规律和对比反应前后粒径大小,并通过傅立叶红外光谱证实了核壳结构的存在。核壳聚合中壳层聚合机理为:单体在加入种子核乳液过程中大部分先在水相中均相成核形成PMMA低聚物,随后由于表面吸附作用而迁移到PBA核表面成为活性中心继续聚合成为壳层。PBA/PMMA core shell latex was prepared with starvefeed semi-batch method.The effect of the shell monomer feed rate and the applied amount of emulsifier on the particle size and its distribution and total number of particles were studied.The evolution of particle size was monitored through particle size analyzer.And the existence of core-shell particles was confirmed through contrasting the theoretical total particle numbers of latex at different stages.The FT-IR spectrum showed the core/shell structure of latex particles as well.The results showed that emulsifier played an important role in the formation of core/shell structure.Homogeneous polymerization of PMMA and new particle formation were favored at high emulsifier.Hydrophobic oligomers of PMMA at low emulsifier were preferentially adsorbed on PBA core particles and that resulted in formation of core shell structure.

关 键 词：核壳结构 半连续法 平均粒径和分布 

分 类 号：TQ316.33[化学工程—高聚物工业]