ISOTROPIC ELECTRICAL-CONDUCTIVITY IN STRUCTURALLY ANISOTROPIC ELECTROCHEMICALLY PREPARED POLYPYRROLE FILMS

Polypyrrole films prepared electrochemically using toluene sulphonate as the dopant exhibit molecular anisotropy on a global scale in that the planes of the pyrrole rings are preferentially aligned parallel to the electrode surface. Electrical conductivity measurements on such highly anisotropic films of polypyrrole/toluene sulphonate films are reported. These show that, although there is substantial molecular anisotropy, there is no significant anisotropy of the electrical conductivity of such films. Possible structural models to account for this difference are discussed.