METHOD FOR PRODUCING THERMOPLASTIC RESIN BODY

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a thermoplastic resin body composed of a thermoplastic resin which is a copolymer of methyl methacrylate and an N-substituted maleimide, which can remove gels generated during polymerization and reduce the number of foreign matters contained while maintaining merits of copolymer formation obtained by selection of bulk polymerization.SOLUTION: The production method comprises: a continuous polymerization step of feeding a monomer mixture containing a methyl methacrylate monomer and a N-substituted maleimide monomer continuously into a polymerization reactor and polymerizing the monomers in the mixture to obtain a thermoplastic resin which is a copolymer of these monomers; a polymerization liquid filtration process of filtering a polymerization liquid having a polymer concentration of 60 mass% or less obtained by the continuous polymerization process; and an evaporation/extrusion step of evaporating and recovering volatile components including monomers from the polymerization liquid after filtration and extrusion molding a resin composition containing the thermoplastic resin.