End-capping of polyarylate carboxyl acid ends by use of aromatic carbonates
US4886875A · kind A · utility
5Cited by
12References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1988 |
| Grant date | Dec 12, 1989 |
| Priority date | — |
| Expiry date | Dec 7, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/20
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for improving the stability of a polyarylate resin by reducing the terminal carboxyl acid group concentration of the polyarylate resin, the process being comprised of melting a mixture of the polyarylate resin and an aromatic carbonate capping agent and reacting the mixture under heat and, if necessary, vacuum until the concentration of the terminal carboxyl acid groups is reduced to less than that of the polyarylate resin prior to end-capping. The process also results in a polyarylate resin with a decreased flammability rating when the aromatic carbonate capping agent is bromine substituted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.