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:
May. 28, 2002
Filed:
Jan. 12, 2001
John Patrick Lemmon, Delanson, NY (US);
Ronald James Wroczynski, Schenectady, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
This invention provides a method for preparing polycarbonates, which utilizes polycondensation catalysts which are derivatized pyridyl triazinyl pyridyl macromolecules with the general formula A [(Triazinyl-Pyridyl)B ], where A is certain alkali metals, B contains a charge balancing sulfonate, carboxylate, or phosphonate group. We have found that this new class of catalysts provide excellent polymerization rates for the preparation of Bisphenol A polycarbonate from the melt polymerization of diphenyl carbonate and Bisphenol A. Moreover, the catalysts of the invention were found to be very selective in substantially reducing the level of branching side reaction, i.e., formation of Fries product, normally associated with the melt polycarbonate process.