Alternating copolymers incorporating dithienogemolodithiophene for field-effect transistor applications

We report the synthesis of an electron-rich fused dithienogemolodithiophene monomer containing straight chain tetradecyl solubilizing groups. Copolymers were prepared with four different electron accepting monomers of varying reduction potential. We report how the choice of acceptor influences the optical properties and molecular energy levels as well as the solid state packing. Field effect transistor devices were fabricated using silver source-drain electrodes, with a promising charge carrier mobility up to 0.26 cm2 V-1 s-1 for films deposited from non-chlorinated solvents. These results suggest dithienogemolodithiophene is a useful building block for the development of high performance semiconducting polymers.