Patent ID: 7557174
Filing Date: 2009-07-07
Classification: C08G

Abstract:
1. A method for preparing a composition comprising a carboxy-terminated oligomeric polyester, said method comprising heating a reaction mixture to a temperature in a range from about 140 to 300° C., said reaction comprising a transition metal alkoxide Lewis acid catalyst; a diacid selected from the group consisting of diacids of formula IV and formula V wherein, R 3 and R 4 are independently at each occurrence a halogen atom, a nitro group, a cyano group, a C 1 -C 12 aliphatic radical, a C 3 -C 12 cycloaliphatic radical, or a C 3 -C 12 aromatic radical; “b” is an integer from 0 to 4; and “c” is an integer from 0 to 4; a diol having formula VIII wherein R 2 is an aromatic radical of formula IX wherein R 7 is independently at each occurrence a halogen atom, a nitro group, a cyano group, a C 1 -C 14 aliphatic radical, a C 4 -C 14 cycloaliphatic radical, or a C 6 -C 14 aromatic radical; and “f” is an integer from 0 to 4; and a diaryl carbonate has formula VI wherein R 5 and R 6 are independently at each occurrence a halogen atom, a nitro group, a cyano group, C 1 -C 20 aliphatic radical, C 3 -C 20 cycloaliphatic radical, or a C 6 -C 20 aromatic radical; “d” is an integer from 0 to 5; and “e” is an integer from 0 to 5; and wherein said diacid and said diol are present in an amount corresponding to a molar ratio of diacid to diol of between about 10% to about 40% excess diacid based on the amount of diol.