US 7,498,400 B2
	Method of preparing polycarbonate
Bernd Jansen, Bergen Op Zoom (Netherlands); Jan Henk Kamps, Bergen op Zoom (Netherlands); Edward Kung, Bergen op Zoom (Netherlands); Patrick Joseph McCloskey, Watervliet, N.Y. (US); and Paul Michael Smigelski, Jr., Schenectady, N.Y. (US)
Assigned to Sabic Innovative Plastics IP B.V., Bergen op Zoom (Netherlands)
Filed on Jun. 30, 2006, as Appl. No. 11/427,885.
Prior Publication US 2008/0004418 A1, Jan. 03, 2008
Int. Cl. C08G 64/00 (2006.01); C08G 63/02 (2006.01)

U.S. Cl. 528—196  [264/176.1; 264/219; 528/198]

44 Claims

1. A method for preparing a polycarbonate comprising reacting a dihydroxy reaction component comprising a dihydroxy compound with carbonate reaction component comprising an activated diaryl carbonate in the presence of an esterification catalyst to produce a polycarbonate, wherein the carbonate reaction component and the dihydroxy reaction component are reacted in the presence of a monofunctional chainstopper, said chainstopper being present in an amount effective to yield a polycarbonate in which from 35 to 65% of the total number of end groups are derived from the monofunctional chainstopper.