ELECTRONICALLY CONDUCTING POLYMERS CONTAINING CONJUGATED BITHIAZOLE MOIETIES FROM BIS(THIENYL)BITHIAZOLES

Bithiazole-containing polymers prepared by electrochemical polymerization of 5,5'-bis(2-thienyl)-4,4'-dimethyl-2,2'-bithiazole (Ia) and 5,5'-bis(3-methoxy-2-thienyl)-4,4'-dimethyl-2,2'-bithiazole (Ib) exhibit good conductivities and stable electrochemistry. The redox potential of poly-Ia (ca. 0.8 V vs SCE) is between the values reported for polythiophene and poly(alpha-bithiophene). The methoxy substituents on the thiophenes of Ib increase its solubility and lower the redox potential of the resulting polymer. The morphology, redox potential, and conductivity of poly-Ib are strongly influenced by the electrolyte used in the polymerization. The maximum conductivity of poly-Ib is ca. 0.01 S cm-1, comparable to that of poly(alpha-terthiophene). It therefore appears that the nitrogen atoms in the conduction pathway have little influence on the redox potential and conductivity of thiophene/thiazole copolymers.