Korea Kumho Petrochemical Co., Ltd.

Seonkyeong Cheong

Young-Hoon Ko

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&lt;m/(m+n)&lt;1 and 0&lt;n/(m+n)&lt;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.

Growing community of inventors

Taejeon, South Korea

Seonkyeong Cheong