采用乳液聚合法制备丙烯酸丁酯-苯乙烯-丙烯腈(ASA)核壳接枝共聚物.考察了不同乳化剂对聚丙烯酸丁酯(PBA)胶乳粒径大小与分布的影响,不同乳化剂、引发剂体系和加料方式对ASA枝壳形貌和接枝效果的影响.结果表明:乳化剂质量相同时,采用十二烷基硫酸钠(SDS)乳化剂制备的PBA胶乳粒子粒径小、分布窄；核层种子胶乳采用阴离子型乳化剂SDS,壳层采用非离子型乳化剂烷基酚聚氧乙烯基醚,制备的ASA接枝率高,核壳结构均匀、完整；采用氧化还原引发剂体系的接枝效果优于采用过硫酸钾引发剂；壳层单体采用预溶胀法加料方式,所得核壳形貌最佳,核壳界面有过渡层,所制ASA有两个玻璃化转变温度(Tg),而且采用预溶胀法所制ASA的两个Tg间的间距更小.%A series of acrylate-styrene-acrylonitrile (ASA) graft copolymers having core-shell structure were synthesized via emulsion polymerization. The dependence of particle size and its distribution of poly-(butyl methacrylate) (PBA) latexes on variety of emulsifiers and the influences of the emulsifiers, initiator systems and monomer addition modes on the core-shell morphology and grafting effect of ASA were studied. The results indicate that the PBA latex synthesized with sodium dodecyl sulfate (SDS) as emulsifier has smaller particle sizes and narrower size distribution even the emulsifier's mass is identical to its counterparts.. The ASA latex acquires high grafting degree and homogeneous and complete core-shell structure in the case of adopting anionic emulsifier SDS for seed latex in the core and non-ionic emulsifier alkylphenol ethoxylate (OP-10) for the shell. Redox system as initiator has the advantage over potassium persulfate in the grafting efficiency of the ASA latex. The ASA latex having optimal core-shell morphology is obtained when adding monomers of the shell in pre-swelling method, in such a case, a transition layer forms on the interface between of the core and shell. The ASA latex so prepared has two glass-transition temperatures which has rather small interval between them when utilizing the pre-swelling method in the latex preparation.
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