Reduction of reaction by-products in polycarbonate resins
US6590068B2 · kind B2 · utility
23Cited by
3References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2001 |
| Grant date | Jul 8, 2003 |
| Priority date | — |
| Expiry date | Dec 22, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/307
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polycarbonate resin containing reduced levels of reaction by-products can be prepared by adding to the polycarbonate a scavenging agent having the formula: wherein R1 is alkoxy, phenoxy, benzyloxy or phenyl, and R2 is a substituted or unsubstituted C1-C30 alkyl group, C6-C30 aryl group, C7-C30 aralkyl group or C6-C30 aryloxy group and processing the resulting mixture at an elevated temperature and for a period of time such that the scavenging agent reacts with linear Fries products to produce capped linear Fries products, and with residual phenols (monohydric or dihydric) to produce capped phenols and ortho-substituted phenols.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.