| 摘要 |
PURPOSE:To improve the optical characteristics, heat resistance, moisture resistance, impact strength, moldability, etc., by reacting a specific dihydric phenol, a carbonic ester-forming compd., and a carboxylated polyfunctional org. compd. CONSTITUTION:A dihydric phenol of formula I (wherein X is a group selected from formulas II to V; and R<1> and R<2> are each H or 1-6C alkyl) (e.g. bisphenol A) is reacted with a carbonic ester-forming compd. (e.g. phosgene) in the presence of an acid acceptor in a solvent at 10-50 deg.C to give an oligomer having a degree of polymn. of 1-10 and reactive chloroformate groups at its terminals. Then, the oligomer is reacted with a polyfunctional, at least trifunctional, org. compd. having a carboxyl group or a group which, on hydrolysis, forms a carboxyl group, the dihydric phenol, and the carbonic ester-forming compd. at 10-50 deg.C for 0.1-2hr, giving the title material comprising a branched polycarbonate resin. |
