CONDUCTING BIPYRIDINE-BITHIOPHENE COPOLYMERS

The synthesis and electrochemical polymerization of 6,6'-bis(2''-thien yf)-3,3'-bipyridine (2) and 6,6'-bis(2''-thienyl)-2,2'-bipyridine (3) are reported. Cyclic voltammetry shows that the resulting polymers hav e high bandgaps (3.0 and 3.2 eV, respectively) and are unstable in the ir p-doped (oxidized) states. Both polymers are stable when n-doped, b ut electronic conductivities determined by impedance spectroscopy were only ca. 3 x 10(-8) S cm(-2) Surprisingly, the greater conjugation in poly-2, which is demonstrated by its lower bandgap, does not lead to enhanced conductivity.