| 摘要 |
PURPOSE:To obtain a novel copolymer having good moldability and giving a molded article having excellent gas-barrier property and heat-deformation resistance, by polymerizing a mixture of methacrylonitrile and an alkyl acrylate under a specific condition. CONSTITUTION:A mixture of (A) methacrylonitrile or a methacrylonitrile mixture containing <=30wt% arcylonitrile and (B) an alkyl acrylate or an alkyl acrylate mixture containing <=80% alkyl methacrylate is continuously added to an aqueous medium containing an emulsifier and polymerized at 50-90 deg.C in the presence of a polymerization initiator (e.g. ammonium persulfate) to obtain the objective novel copolymer composed of a mixed unsaturated ester unit consisting of the mixed nitrile unit of the component A and the alkyl mechancrylate unit of the component B at a weight ratio (A/B) of 95/5-70/30 and having a weight-average molecular weight of 60,000-200,000. |
