Patent ID: 7534503

Claim:
A monomer having general formula I which may be substituted or unsubstituted: where E and E′ are the same or different and are reactive groups capable of undergoing chain extension; X is O, S, NR 5 , R 5 C—CR 6 or R 5 C═CR 6 ; Y is O, S, NR 7 , R 7 C—CR 8 or R 7 C═CR 8 ; R 5 , R 6 , R 7 and R 8 are the same or different and each is independently H or a substituent group; each Ar is the same or different and is independently a substituted or unsubstituted aryl or heteroaryl group; and the reactive groups are selected from reactive halide functional groups and reactive boron derivative groups.