摘要： 采用半连续种子乳液聚合法合成了核壳型聚丙烯酸酯复合乳液，系统考察了引发剂(过硫酸铵)用量对乳液聚合过程中单体转化率、聚合稳定性、乳胶粒粒径及其分布、乳液黏度及 Zeta电位的影响，探讨了其内在影响机制，并采用红外(FT-IR)、差示扫描量热(DSC)及透射电镜(TEM)对乳胶粒的结构进行了表征。结果表明:乳胶粒的 Zeta 电位随着引发剂过硫酸铵用量的增加而增大;合适的引发剂用量可使合成的复合乳胶粒粒径较小且粒径分布较窄;引发剂用量较大会使复合乳胶粒在聚合过程中发生聚并，但所得乳液在贮存过程中稳定性较好;当引发剂用量为 0.4% ~0.8%(占单体混合物的质量分数)时，单体均能参与反应，极少有残余，并且所得乳液呈明显的核壳结构。

关键词: 核壳结构, 引发剂, 复合乳液, 聚丙烯酸酯

Abstract: The core-shell polyacrylate compound latexes were synthesized through semicontinuous seeding emulsion polymerization. The effects of initiator dosage ( ammonium persulfate )on monomer conversion, polymerization stability, latex particle size and its distribution, emulsion viscosity and Zeta potential were investigated, and the underlying mechanisms were discussed. The core-shell particles were characterized by FT-IR. DSC and TEM. The results showed that the latex particles, Zeta potential was in direct proportion to the amount of ammonium persulfate. Smaller latex particle size and narrow size distribution could be obtained using proper ammonium persulfate dosage in the polymerization process. However, large amount of ammonium persulfate would lead to coalescence of composite latex particles in the polymerization process, but better latex storage stability. When the amount of initiator was 0. 4% ~0.8%(mass fraction in monomer mixture), all monomers could participate in reaction with few residual. DSC and TEM determinations showed that the final latexs were core-shell structure.

Key words: core-shell structure, initiator, compound latex, polyacrylate

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