Patent ID: 7354986

Claim:
A copolycarbonate of the formula wherein 5 to 75 mole percent of the total number of R 1 groups is derived from a high Tg monomer of formula (2) wherein R 2 and R 3 are each independently a halogen or a C 1-6 alkyl group, R 4 is a phenyl, and c is 0 to 4; and 25 to 95 mole percent of the R 1 groups are derived from a dihydroxy compound of formula (3) HOâ€”R 5 â€”OHâ€ƒâ€ƒ(3), wherein at least 60% of the R 5 groups are aromatic, and the dihydroxy compound of formula (3) is not the same as the high Tg monomer of formula (2), and wherein the copolycarbonate comprises at least 10% fewer carbonate linkages of formula (4) than would be theoretically obtained in a random copolymer made from the same ratio of the high Tg monomer of formula (2) and the dihydroxy compound of formula (3).