| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for efficiently producing a styrene-based resin of multilayered structure excellent in weather resistance, impact resistance, heat resistance, mechanical strength, etc., especially providing a molded material excellent in transparency and luster, consequently in colorability and improved in heat stability. SOLUTION: This styrene-based resin of multilayered structure is obtained by the following emulsion polymerization of five steps. (1) An emulsion polymerization in which styrene is mixed with a polyfunctional monomer and an amine-based stabilizer copolymerizable with a monomer so as to make a formed copolymer have >=0 deg.C glass transition temperature (Tg), (2) an emulsion polymerization in which a 1-8C (meth)acrylic acid ester is additionally mixed with the polyfunctional monomer and the amine-based stabilizer so as to make a formed copolymer have <=0 deg.C Tg, (3) an emulsion polymerization in which styrene, etc., are copolymerized with the polyfunctional monomer and the amine-based stabilizer so as to make to formed copolymer have >=0 deg.C Tg and 1.50-1.60 refractive index, (4) an emulsion polymerization in which styrene is copolymerized with a vinyl cyanide compound, the polyfunctional monomer and the amine-based stabilizer and (5) an emulsion polymerization in which styrene is copolymerized with the vinyl cyanide compound and the amine-based stabilizer. |
