07498400 is referenced by 1 patents and cites 60 patents.

Polycarbonates incorporating terminal carbonate groups derived from ester-substituted activated carbonates in a transesterification process have unfavorable properties with respect to color, hydrolytic stability and thermal stability, particularly when the polycarbonate containing such end groups is molded. The number of activated carbonate end groups formed during the melt transesterification formation of polycarbonate can be reduced by reacting a dihydroxy compound with an activated diaryl carbonate in the presence of an esterification catalyst to produce a polycarbonate, in the presence of a monohydroxy chainstopper such as para-cumyl phenol in an amount that results in 35 to 65 mol % of the end groups being derived from the monohydroxy chainstopper. Suitably, the reactants are provided such that the molar ratio of activated diaryl carbonate to the total of dihydroxy compound plus ½ the chainstopping reagent that is less than 1.

Title
Method of preparing polycarbonate
Application Number
11/427885
Publication Number
7498400 (B2)
Application Date
June 30, 2006
Publication Date
March 3, 2009
Inventor
Paul Michael Smigelski Jr
Schenectady
NY, US
Patrick Joseph McCloskey
Watervliet
NY, US
Edward Kung
Bergen op Zoom
NL
Jan Henk Kamps
Bergen op Zoom
NL
Bernd Jansen
Bergen Op Zoom
NL
Agent
Marina Larson & Associates
Assignee
Sabic Innovative Plastics IP
NL
IPC
C08G 63/02
C08G 64/00
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