Synthesis and properties of poly(thienylenevinylene) derivatives with hexyl groups

We have synthesized two kinds of soluble poly(thienylenevinylene) derivatives with hexyl groups. As a precursor common to these polymers, 1,2-trans-bis(3-hexylthiophene-2-yl)ethylene (BHTE) was synthesized. Two polymerization methods of Grignard coupling and chemical oxidative coupling were employed. The former gave a soluble polymer with a thienylene-vinylene (TV) sequence in main chain and the cast film of the polymer showed an electrical conductivity of 0.4 S/cm upon an iodine doping ; The latter gave a soluble polymer with a TVT sequence. Casting the polymer gave a free-standing film with a conductivity of 8.7 S/cm after the iodine doping.