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:
Mar. 24, 1998
Filed:
Sep. 30, 1996
Balaram Gupta, Corpus Christi, TX (US);
Matthew J Bylicki, Hampton, NJ (US);
Hoechst Celanese Corp., Somerville, NJ (US);
Abstract
A new process is provided for the formation of aromatic polyesters directly from the reaction of dialkyl ester of an aromatic carboxylic acid with dihydric phenols. The polycondensation is carried out in the presence of (a) a condensing agent; (b) a catalyst selected from the group consisting of derivatives of Group I metals, derivatives of Group IV A metals, derivatives of Group IV B metals, and mixtures thereof; and (c) a co-catalyst selected from the group consisting of methanesulfonic acid, sulfuric acid, p-toluenesulfonic acid, alkanoic acid having the formula, C.sub.n H.sub.x F.sub.y COOH, where n is an integer from 1 to 4, x and y are integers from 0 to 2n+1, and the sum of x and y is 2n+1, and mixtures thereof; at suitable temperature and pressure conditions and for a sufficient period of time to form the aromatic polyester.