| abstract |
(57) [Summary] [PROBLEMS] The present invention provides colorless and transparent, moldability (flowability). And a method for producing the same. The heat-resistant copolymer of the present invention is a copolymer (A) containing 5% by weight or more of a lactone ring structural unit represented by the following general formula (1), and has a glass transition temperature: Is 120 ° C. or higher. Embedded image (In the formula, R is a group selected from a hydrogen atom, a methyl group and an ethyl group.) The method for producing such a heat-resistant copolymer comprises a methacrylic acid ester component unit and a carboxylic acid unsaturated ester component unit. Copolymer (B) Is heated at 180 to 300 ° C., so that the lactone ring structural unit represented by the general formula (1) is 5% by weight. It is characterized by being formed as described above and being modified into a copolymer (A) having a glass transition temperature of 120 ° C. or higher. |