以异戊二烯、苯乙烯、甲基丙烯酸甲酯为聚合单体,通过多步乳液种子聚合,制备了具有典型核壳结构的三元接枝聚合物MIS。胶乳粒子的核心是轻度交联且具低剪切模量的橡胶核,外壳是聚甲基丙烯酸甲酯硬壳层。研究了橡胶相的组成对聚合反应时间、胶乳粒径和玻璃化温度的影响,引发剂的种类对接枝聚合的影响。所得的新型抗冲改性剂可显著提高PVC塑料的力学性能,是1种理想的PVC增韧剂。 Ternary graft polymer MIS with typical core-shell structure was prepared by multistage emulsion seed polymerization using isoprene, styrene and methyl methacrylate as polymerized monomers. The core of the latex particles is a lightly cross-linked rubber core with a low shear modulus, the shell being a polymethylmethacrylate hard shell. The effects of the composition of the rubbery phase on the polymerization reaction time, the particle size and the glass transition temperature of the latex and the kind of initiator on the graft polymerization were investigated. The resulting new impact modifier can significantly improve the mechanical properties of PVC plastic, is an ideal PVC toughening agent.