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AssigneeGeneral Electric Company
InventorsPatrick Joseph McCloskey, Jan Pleun Lens, James Anthony Cella, Jan Henk Kamps, Kathryn Lynn Longley, Narayan Ramesh, Warren William Reilly, Paul Michael Smigelski JR., Marc Brian Wisnudel
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Polycarbonates containing low or undetectable levels of Fries rearrangement products and comprising repeat units derived from one or more of resorcinol, hydroquinone, methylhydroquinone, bisphenol A, and 4,4′-biphenol have been prepared by the melt reaction of one or more of the aforementioned dihydroxy aromatic compounds with an ester-substituted diaryl carbonate such as bis-methyl salicyl carbonate. Low, or in many instances undetectable, levels of Fries rearrangement products are found in the product polycarbonates obtained as the combined result of a highly effective catalyst system which suppresses the Fries reaction and the use of lower melt polymerization temperatures relative to temperatures required for the analogous polymerization reactions using diphenyl carbonate.
A method of preparing a polycarbonate, said method comprising heating a mixture comprising a catalyst, at least one diaryl carbonate having structure I
A method of preparing a polycarbonate comprising repeat units derived from resorcinol and bisphenol A, said method comprising heating a mixture of resorcinol and bisphenol A with from about 0.8 to about 1.10 moles of bis-methyl salicyl carbonate per mole bisphenol A and resorcinol combined, at a temperature in a range between about 140° C. and about 240° C., and a pressure in a range between about 0.01 mmHg and about 760 mmHg, in the presence of a catalyst comprising sodium hydroxide and a quaternary ammonium compound or quaternary phosphonium compound, said sodium hydroxide being present in an amount in a range between about 1×10−5 and about 1×10−8 moles sodium hydroxide per mole of bisphenol A and resorcinol combined, said quaternary ammonium compound or quaternary phosphonium compound being present in an amount between about 2.5×10−3 and about 2.5×10−6 moles of quaternary ammonium compound or quaternary phosphonium per mole of bisphenol A and resorcinol combined.
A method of preparing a polycarbonate terpolymer comprising repeat units derived from resorcinol, hydroquinone and bisphenol A, said method comprising heating a mixture of resorcinol, hydroquinone and bisphenol A with from about 0.8 to about 1.10 moles of bis-methyl salicyl carbonate per mole of bisphenol A, hydroquinone, and resorcinol combined, at a temperature in a range between about 140° C. and about 240° C., and a pressure in a range between about 0.01 mmHg and about 760 mmHg, in the presence of a catalyst comprising sodium hydroxide and a quaternary ammonium compound or quaternary phosphonium compound, said sodium hydroxide being present in an amount in a range between about 1×10−5 and about 1×10−8 moles sodium hydroxide per mole of bisphenol A, hydroquinone, and resorcinol combined, said quaternary ammonium compound or quaternary phosphonium compound being present in an amount between about 2.5×10−3 and about 2.5×10−6 moles of quaternary ammonium compound or quaternary phosphonium per mole of bisphenol A, hydroquinone, and resorcinol combined.
Dependencies are inferred from the claim text.