| 摘要 |
PURPOSE:To obtain a composition having remarkably improved impact resistance while keeping high transparency, surface gloss, rigidity, surface hardness, etc., of the base resin, by compounding a methacrylic resin with a graft copolymer having a specific multi-layer structure. CONSTITUTION:A crosslinking mixture composed of a monomer such as benzyl methacrylate, etc., an alkyl acrylate and a polyfunctional monomer having acryloyloxy group is polymerized in the 1st stage. A mixture of a 1-8C alkyl acrylate, styrene, etc., and a graft-crosslinkable monomer is subjected to polymerization in the presence of the 1st stage polymerization product to obtain an elastic polymer having double-layer structure. 30-900pts.wt. of a 1-4C alkyl methacrylate, etc., is added to a reaction system in >=1 divided portions and polymerized in >=3 stages in the presence of 100pts.wt. of the elastic polymer produced in the 2nd stage polymerization. The obtained graft copolymer having multi-layer structure is compounded with a methacrylic resin containing 80-100wt% methyl methacrylate to obtain the objective composition containing the double-layered elastic polymer at an amount of 1-70wt%.
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