梯度核壳乳液的合成研究  

Studies of graded core-shell emulsion

作　　者：孙志娟[1] 张心亚[1] 黄洪[1] 陈焕钦[1] 

机构地区：[1]华南理工大学化工研究所,广州510640

出　　处：《北京化工大学学报（自然科学版）》2006年第3期23-27,共5页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：广东省科技厅科技计划项目(2003B10506)

摘　　要：采用多步乳液聚合法合成了具有核/中间层/壳梯度结构的纯丙烯酸酯乳液,并对影响聚合物粒子核壳结构的主要因素进行了探讨。实验发现硬单体和软单体在选用多步乳液聚合技术时,可形成具有梯度的硬核软壳结构型乳液,降低了乳液的最低成膜温度;采用壳预乳化法添加乳化剂可使其在不同的反应阶段得到合理分配,有利于维持反应体系稳定,并避免在反应后期生成新粒子;当乳化剂用量为3%时,凝聚率仅有1%,所得乳液粒径在100 nm左右且粒径分布均匀。同时,通过粒度仪和透射电镜(TEM)对粒子结构进行分析并验证了其梯度核壳结构形态。An acrylate emulsion with a graded core-mesosphere-shell structure has been synthesized by multistage emulsion polymerization, and the main factors affecting the core-shell structure of the polymer particles have been discussed. The experimental results show that use of multi-stage emulsion polymerization allows the synthesis of a graded core （hard）-shell （soft） emulsion with a hard monomer （methyl methacrylate） and a soft polymer （butyl acrylate） and the minimum film forming temperature （MFT） can be reduced significantly. Emulsifiers can be well distributed at different stages by means of shell pre-emulsification which can improve the stability of the system, and avoid the formation of new small particles in the subsequent reaction process. When the amount of emulsifier is 3 % （based on the amount of monomer）, the coagulation rate is only 1% and the particle size is about 100 nm with a narrow distribution. The structure of the polymer particles was analyzed using a particle size analyzer and by transmission electron microscopy （TEM）, which clearly demonstrate the presence of the graded core-mesosphere-sheU structure.

关 键 词：多步乳液聚合 梯度核壳乳液 最低成膜温度 乳胶涂料 

分 类 号：TQ630.1[化学工程—精细化工]