| abstract |
PURPOSE: A specific compound is used as an ester-interchange catalyst to produce discoloration-free polycarbonate using usual equipment made of stainless steel with industrial advantage. n CONSTITUTION: In the production of polycarbonate by the ester-interchange method from (A) a dihydroxyaryl compound such as bisphenol A and (B) a carbonic acid diester such as diphenyl carbonate, (C) an iminocarboxylic acid or its metal salt of the formula (n is 1W3) such as trisodium nitrilotriacetate or ethylenediaminetetra-acetice acid is used as an ester-interchange catalyst, preferably in an amount of 0.001W0.1mol% based on component A. When necessary, additionally, an organic acid salt, inorganic acid salt, oxide, hydroxide, hydride or alcoholate is used in combination bined as a cocatalyst. n COPYRIGHT: (C)1980,JPO&Japio |