Patent ID: 6307006
Filing Date: 2001-10-23
Classification: C08G

Abstract:
In the process of producing branched polycarbonates by melt transesterification from at least one diphenol, diaryl carbonate and a branching agent, and in the optional presence of a catalyst, at temperatures between 80 to 400.degree. C. and at pressures between 1 and 0.01 mbar, the improvement comprising using as branching agent, about 0.05 to 2 moles per 100 moles of said diphenol, at least one member selected from the group consisting of (i) an aliphatic alcohol conforming to ##STR7##wherein R' is a single bond, a linear C.sub.1-36 -alkylene or a branched C.sub.3-36 -alkylene and R and R"" independently denote H, linear C.sub.1-36 -alkyl, branched C.sub.3-36 -alkyl or R'""-OH where R'"" is a linear C.sub.1-36 -alkylene or a branched C.sub.3-36 -alkylene, and n is 2,3,4 or 5, and (ii) the ether of said (i) which is formed by self-condensation.