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:
Nov. 02, 2004
Filed:
Mar. 25, 2002
James Manio Silva, Clifton Park, NY (US);
David Michel Dardaris, Ballston Spa, NY (US);
Gregory Allen O'Neil, Clifton Park, NY (US);
Paul Dean Sybert, Evansville, IN (US);
Zhaohui Su, Evansville, IN (US);
General Electric Company, Schenectady, NY (US);
Abstract
Thermally stable block copolyestercarbonates comprising chain members derived from at least one dihydroxy-substituted aromatic hydrocarbon moiety and at least one aromatic dicarboxylic acid moiety, said polymer being substantially free of anhydride linkages linking at least two mers of the polyester chain segments, are prepared by a method comprising the steps of: (a) preparing a hydroxy-terminated polyester intermediate comprising structural units derived from at least one dihydroxy-substituted aromatic hydrocarbon moiety and at least one aromatic dicarboxylic acid moiety; and (b) conducting a reaction of the polyester intermediate with phosgene in a reaction mixture comprising water, a substantially water-immiscible organic solvent, and a base, wherein base and phosgene are added simultaneously to the reaction mixture at a substantially constant molar ratio of base to phosgene for a time period of at least about 60% of the total amount of phosgene added.