PROCESS FOR THE PRODUCTION OF HEAT RESISTANT THERMOPLASTIC COPOLYMER

摘要

A process for the production of a thermoplastic copolymer having excellent heat distortion resistance which comprises heat-treating a raw copolymer comprising a vinyl monomer unit including methacrylic and/or acrylic acid unit in the presence of a specific ring-closing promoter selected from basic compounds, whereby the methacrylic and/or acrylic acid unit being converted into six-membered cyclic anhydride unit. The copolymer has excellent heat distortion resistance, transparency, mechanical properties and processability, and can give formed product without splash on the surface, and is useful for the production of various parts, such as automobile parts, electrical parts, industrial parts, and miscellaneous goods.