Polycarbonate and process for producing the same
US5942594A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1998 |
| Grant date | Aug 24, 1999 |
| Priority date | — |
| Expiry date | Mar 19, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/307
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polycarbonate exhibiting excellent fluidity and moisture resistance and a process for efficiently producing the polycarbonate are provided. The polycarbonate has a main chain comprising a repeating unit represented by general formula (I): ##STR1## wherein R.sup.1 and R.sup.2 each represents hydrogen atom or an alkyl group having 1 to 7 carbon atoms; contains 100 ppm by weight or less of a unit of a phenyl salicylate structure expressed by formula (II): ##STR2## in the main chain; and has a viscosity-average molecular weight of 10,000 or more. The polycarbonate is produced in accordance with a process comprising transesterification in the presence of a catalyst comprising a combination of an organic basic compound containing nitrogen and a quaternary phosphonium salt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.