PREPARATION AND CHARACTERIZATION OF POLY(3-ARYLTHIOPHENE)S

A series of 3-(p-X-phenyl)thiophene monomers (X = -CMe3, -Me, -OMe, -H , -F, -Cl, -Br, -CF3, -SO2Me) was electrochemically polymerized to for m polymer films that could be reversibly reduced and oxidized (n- and p-doped). The oxidation potentials of the monomers and formal potentia ls of the n- and p-doping processes of polymers were correlated with t he resonance and inductive effects of the substituents on the phenyl r ing. The charge obtained by integrating the cyclic voltammetric peak w as affected by the polymerization efficiency and, in some cases, the i on transport rate. The ionic resistance of poly[3-(p-chlorophenyl)thio phene] (PCPT) and poly[3-(p-fluorophenyl)thiophene] (PFPT) films measu red by impedance spectroscopy, together with scanning electron microsc opy results, demonstrate that the ion transport in these films is affe cted by their morphology.