| 摘要 |
PURPOSE:To produce a thermoplastic resin excellent in heat stability and hue, by effective aqueous emulsion polymerization of alpha-methylstyrene, a vinyl cyanide monomer and other copolymerizable vinyl monomers under a specified condition. CONSTITUTION:The aqueous emulsion polymerization of 100pts.wt. monomer mixture comprising 50-80wt% alpha-methylstyrene itself or alpha-methylstyrene containing a small amount of styrene, 15-35wt% vinyl cyanide monomer (e.g., acrylonitrile) and 0-30wt% other copolymerizable vinyl monomers (e.g., acrylate ester) is effected in the presence of 0.001-0.3pts.wt. persulfate (e.g., sodium persulfate) and 0.5-5pts.wt. emulsifier (e.g., sodium dodecylbenzenesulfonate). When the conversion reaches 50-98%, 0.01-0.30pts.wt. oil-soluble catalyst (e.g., octanoyl peroxide) is added to the polymerization system, and the polymerization reaction is completed. |
