Method for producing an aromatic polycarbonate having improved melt stability

Abstract

Disclosed is a method for producing an aromatic polycarbonate, which comprises: reacting a feedstock dialkyl carbonate with a feedstock phenol in the presence of a catalyst to produce diphenyl carbonate, wherein a phenol mixture comprising component phenols which are different in supply source is used as the feedstock phenol, and polymerizing the produced diphenyl carbonate with an aromatic dihydroxy compound to produce an aromatic polycarbonate while producing phenol as a by-product, wherein the by-product phenol obtained in the production of the aromatic polycarbonate is used as a component phenol of the feedstock phenol mixture for producing diphenyl carbonate, and wherein the content of the by-product phenol in the feedstock phenol mixture is controlled to a level in the range of from 70 to 99% by weight. According to the method of the present invention, an aromatic polycarbonate having excellent melt stability at high temperatures can be stably produced. In the method of the present invention, a by-product phenol obtained in the production of an aromatic polycarbonate is effectively utilized for obtaining diphenyl carbonate used for producing an aromatic polycarbonate.

Dependencies are inferred from the claim text.