COPOLYCARBONATES OF PHENOLPHTHALEIN POLYCARBONATES AND OTHER POLYCARBONATES

摘要

This invention is directed to a copolycarbonate of a polycarbonate of a trityldiol such as phenolphthalein and a polycarbonate of another diol such as bisphenol-A and to a process for preparing the copolycarbonate. The copolycarbonate is prepared by contacting the starting polycarbonates under conditions of shear and/or temperature sufficient to cause reaction of the polycarbonates to form a copolycarbonate of the polycarbonates. The copolycarbonates of this invention exhibit generally improved impact resistance, clarity and flame resistance as compared with the starting polycarbonates or with a copolycarbonate from polycarbonate copolymers of the same diols. Applications of particular interest for the utilization of the copolycarbonates of this invention are in aircraft parts and automobile parts requiring higher heat resistance than possessed by the homopolymers of bisphenol-A and similar diols.