Salts of aryl sulfonic acids as polymerization catalysts
AssigneeGeneral Electric Company
InventorsPatrick Joseph McCloskey, Paul Michael Smigelski, Jr., Timothy Brydon Burnell
Life of this patent
Estimating the term…
Abstract
This invention relates to salts of aryl sulfonic acids useful in catalyst systems in melt polymerizations. Suitable alkali metal salts of aryl sulfonic acids include alkali metal salts of p-toluenesulfonic acid. The invention further relates to polycarbonates prepared using the catalyst systems of the present invention, and articles made from these polycarbonates.
Claims12
A method for the preparation of polycarbonate by the melt process comprising
- a) heating, in one or more stages, a mixture comprising a diphenol and a diarylcarbonate;
- and
- b) introducing into the mixture of a), in the same stage or different stages 1) a catalytically effective amount of an alkali and/or alkali earth metal salt of an aryl sulfonic acid.
A method of reducing the Fries content of a polycarbonate comprising preparing a polycarbonate by a melt process, the method comprising:
- a) heating, in one or more stages, a mixture comprising a diphenol and a diarylcarbonate;
- and
- b) introducing into the mixture of a), in the same stage or different stages 1) a catalytically effective amount of an alkali and/or alkali earth metal salt of an aryl sulfonic acid.
A method of reducing the branched side products of polycarbonate comprising
- a) heating, in one or more stages, a mixture comprising a diphenol and a diarylcarbonate;
- and
- b) introducing into the mixture of a), in the same stage or different stages 1) a catalytically effective amount of an alkali and/or alkali earth metal salt of an aryl sulfonic acid.
Dependencies are inferred from the claim text.