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:
Dec. 29, 1998
Filed:
Jan. 15, 1997
Applicant:
Inventors:
Ray E Drumright, Midland, MI (US);
James Lee Brewbaker, Midland, MI (US);
William B Marshall, Midland, MI (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ; C08G / ; C08G / ;
U.S. Cl.
CPC ...
528286 ; 528192 ; 528194 ; 528302 ; 528308 ;
Abstract
A process for preparing a polyester which includes the step of heating a reaction mixture comprising (i) diesters of dihydric phenols and C.sub.1-10 aliphatic monoacids, (ii) aromatic dicarboxylic acids, and (iii) a catalytic amount of an organic cation-containing salt at a temperature above the melt temperature of the diesters, under reaction conditions sufficient to form the corresponding polyester. Use of this process subjects the polymers prepared thereby to a thermal history which causes relatively little deterioration of the polymer's properties.