Synthesis of methacrylate and silicone polymers with pendant thiophene groups

We report the preparation of copolymers of hexenylthiophene with methylacrylate using various radical initiators. The resulting polymers were readily soluble and in acetonitrile were electropolymerized to give passivating or conducting films depending on the proportion of thiophene groups in the copolymer. Chemical polymerization with FeCl3 led to a polymer with conductivity 0.6 S cm−1 after doping. We also describe the synthesis of (R1R2SiO)n polymers with R1=CH3 and R2=(CH2)n(C4H3S). The thiophene groups are connected at the 3-position. The corresponding alkenylthiophene starting material undergoes hydrosilylation with the readily available and well-characterized polysilicones (R1HSiO)n in the presence of a catalyst. The polymers could be oxidized and doped chemically or electrochemically to produce black materials with surprisingly low conductivity (10−5 S cm−1) suggesting interchain coupling of thiophene groups.