Patent · US Expired

Melt, catalytic process for preparing polycarbonates from carbonic acid diester

US5097002A · kind A · utility

56Cited by
12References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 10, 1991
Grant dateMar 17, 1992
Priority date
Expiry dateMay 10, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G64/307
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for preparing polycarbonates according to the invention by melt polycondensation of aromatic dihydroxy compounds and carbonic acid diesters, is characterized by using an aromatic dihydroxy compound and a carbonic acid diester, wherein the combined content of hydrolyzable chlorine in those monomers falls within the particular range. Another process for preparing polycarbonates according to the invention by melt polycondensation of aromatic dihydroxy compounds and carbonic acid diesters, is characterized by using a catalyst comprising (a) a nitrogen containing basic compound and (b) aromatic dihydroxy compound of an alkali metal or alkaline earth metal compound, or (a) and (b) and (c) boric acid or boric ester.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.