Separation of cyclic oligomeric carbonate from high molecular weight polycarbonate
US4663433A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1985 |
| Grant date | May 5, 1987 |
| Priority date | — |
| Expiry date | Dec 23, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/406
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for separating cyclic oligomeric dihydric phenol carbonate from high molecular weight linear aromatic polycarbonate which comprises admixing a solution of aromatic polycarbonate and oligomeric dihydric phenol carbonate in a halogenated organic solvent with an antisolvent selected from the group consisting of butanol, isobutanol and an alkane of from five to about nine carbon atoms, inclusive, separating the solid aromatic polycarbonate from the solution of cyclic oligomeric dihydric phenol carbonate, increasing the antisolvent to halogenated organic solvent ratio and thereby precipitate the cyclic oligomeric dihydric phenol carbonate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.