Patent ID: 7820769

Claim:
A copolymer comprising (a) one or more pendant group segments and (b) one or more polyol segments, each of said segments being linked to one or more further segments which may be the same or different, wherein said one or more pendant group segments are the same or different and are siloxane segments, wherein each of said siloxane segments comprises a siloxane moiety which is either a linear siloxane with a molecular weight of up to 2000 Daltons, a silsesquioxane cage or a partial silsesquioxane cage, said moiety being attached to the copolymer backbone either directly or via a pendant arm that does not contain any ether groups, and wherein when said moiety is a silsesquioxane cage or partial silsesquioxane cage, then the molar ratio of pendant group segments to polyol segments is 1:X wherein X is 10 or more, and wherein when said moiety is a linear siloxane, then the component (b) comprises one or more polycarbonate segments.