Aromatic polycarbonate resin of improved color
US5455324A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 1993 |
| Grant date | Oct 3, 1995 |
| Priority date | — |
| Expiry date | Aug 25, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/307
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Disclosed herein is an aromatic polycarbonate resin containing benzophenone and benzoate ester derivatives which have a molecular weight less than 1,000, each in an amount of 100 ppm or less. Also disclosed is a process for preparing an aromatic polycarbonate resin from an aromatic dihydroxy compound and a carbonate diester in which the benzophenone derivative content is 100 ppm or less by transesterification, comprising preparing a polycarbonate prepolymer having a viscosity average molecular weight of 5,000 to 20,000 using an iminocarboxylic acid or salt thereof as a transesterification catalyst and polymerizing the prepolymer in an extruder. The aromatic polycarbonate is colorless and transparent and is suitable for extrusion molding.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.