Benzodithiophene homopolymers synthesized by Grignard metathesis (GRIM) and Stille coupling polymerizations

Poly{4,8-bis(95-dodecylthiophene-2-yl)benzo[1,2-b:4,5-b′]dithiophene} has been synthesized by both Grignard metathesis (P1) and Stille coupling polymerizations (P2). Polymers P1 and P2 were characterized and their optoelectronic properties, charge carrier mobilities, and photovoltaic properties were compared. The field-effect mobilities of the polymers were measured on both untreated and heptadecafluoro-1,1,2,2-tetrahydro-decyl-1-trimethoxysilane (FS) treated organic field effect transistor (OFET) devices. The polymers were also evaluated in bulk heterojunction (BHJ) solar cells with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor.