Flame-retardant wholly aromatic polyester and method for preparing the same
US5677416A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1996 |
| Grant date | Oct 14, 1997 |
| Priority date | — |
| Expiry date | Oct 30, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/6926
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
There are disclosed a wholly aromatic polyester represented by formula I with enhanced flame retardance and chemical stability, and a method for the preparing the same. The polymer is prepared in interface polymerization wherein an alkali aqueous phase containing cyclotriphosphagene-containing bisphenols is in contact with an organic phase containing aromatic dicarboxylic acid chlorides in the presence of a phase transfer catalyst. ##STR1## wherein m and n each are an integer which satisfies the following conditions: 0<m/(m+n)<1 and 0<n/(m+n)<1; X represents --O--, --S--, --SO.sub.2 --, --SO--, --CO--, an alkylene group of C.sub.1-4, or an alkylidene group of C.sub.1-4 ; and R.sub.1, R.sub.2, R.sub.3, R.sub.1 ', R.sub.2 ', R.sub.3 ' and R.sub.4 ' are the same or different, and represent a hydrogen atom, a halogen atom, or an alkyl group of C.sub.1-4 or the derivatives thereof, respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.