PROCESS FOR PRODUCING COPOLYMER OF STYRENE AND MALEIMIDE EXCELLENT IN OPTICAL PROPERTY, THERMAL PROPERTY, AND MECHANICAL PROPERTY BY USING SUPERCRITICAL FLUID

摘要

PURPOSE: A process is provided to produce a copolymer of styrene and maleimide excellent in an optical property, thermal property, and mechanical property by using a supercritical fluid, which can be performed at a low temperature and can easily remove residual amines and byproducts. CONSTITUTION: The process comprises the steps of: mixing a copolymer of styrene and maleic anhydride with a supercritical imidization agent or with an imidization agent and a supercritical carbon dioxide or with the supercritical imidization agent and the supercritical carbon dioxide; and removing residual amines and byproduct. The copolymer of styrene and maleic anhydride contains 5-50wt% of the maleic anhydride monomer and 95-50wt% of the styrene monomer. And the produced copolymer of styrene and maleimide has a weight average molecular weight of 5,000-300,000.