The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 14, 1997
Filed:
Oct. 30, 1996
Young-Hoon Ko, Taejeon, KR;
Seonkyeong Cheong, Taejeon, KR;
Korea Kumho Petrochemical Co., Ltd., Seoul, KR;
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.