Conjugated polymers based on terthiophene and their applications

A conjugated polymer containing 5 or more repeating units of Formula (II):

• wherein Ar1 and Ar2 are aromatic units that are not thiophene, wherein a * bond is a bond to an additional unit of Formula (II) and there are three thiophene units between each Ar1 unit and Ar2 unit in the conjugated polymer, Ar1 and Ar2 are different from each other and independently selected from:
• M5, M6, M7, M8, M9, M10, M11, M12 are H atom;
• and
• R1 and R2 are independently selected from branched alkyl groups with 6-40 C atoms, in which one of more non-adjacent C atoms are optionally replaced by —O—, —S—, —C(O)—, —C(O—)—O—, —O—C(O)—, —O—C(O)—O—, —CR0=CR00- or—C≡C— and in which one or more H atoms are optionally replaced by F, Cl, Br, I or CN, or denote aryl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl having 4 to 30 ring atoms that is unsubstituted or substituted by one or more non-aromatic groups.