Patent ID: 6566563
Filing Date: 2003-05-20
Classification: C08G

Abstract:
A process for making OH-terminated compounds comprising:(a) combining at least one CH2OH-terminated diol and a titanium-containing catalyst to form a reaction mixture; (b) heating the reaction mixture to a temperature of from 110 to 160Â° C. to form a heated reaction mixture; (c) continuously adding dimethyl carbonate to the heated reaction mixture; (d) continuously distilling all methanol released from the heated reaction mixture; (e) heating the reaction mixture to a temperature of from 190 to 240Â° C. to form an OH-terminated product; (f) removing unreleased methanol and dimethyl carbonate from the reaction mixture under a pressure of less than 100 mbar; and (g) deactivating the titanium-containing catalyst by adding from 0.8 to 2 equivalents, based on the catalyst, of a 1 to 20% by weight aqueous solution of phosphoric acid to the reaction mixture, at a temperature of from 80 to 120Â° C.