Patent ID: 8309672

Claim:
A conjugated polymer comprising: a polymer backbone consisting essentially of a repeat unit of the formula (I) wherein R 1 , R 2 , R′ 1 , R′ 2 , R 3 and R 4 are each independently a) selected from the group consisting of: alkyl, alkenyl, alkoxy, alkynyl, aryl, alkylaryl, arylalkyl, and polyalkylene oxide, each optionally substituted, which may contain one or more heteroatoms; or b) not present; A, A 1 , B, B 1 , C and D are each independently H, —SiR′R″R′″, or a polar substituent selected from the group consisting of —N + R′R″R′″, a guanidinium group, histidine, a polyamine, a pyridinium group, and a sulfonium group; E and F are each independently selected from the group consisting of: not present, —O—, —S—, —C(O)—, —C(O)O—, —N(R′)—, and —Si(R′)(R″)—; X is selected from the group consisting of —O—, —S—, —Se—, —N(R′)— and —C(R′)(R″)—; and Y and Z are each —N═; wherein R′, R″ and R′″ are each independently selected from the group consisting of hydrogen, C 1-12 alkyl, C 1-12 alkoxy, and C 3-10 cycloalkyl; the repeat unit comprises at least one of the polar substituent; and the repeat unit is at a density sufficient to render said polymer soluble in a polar medium having a polarity of at least that of ethyl acetate.