STRUCTURE, STRENGTH AND ELECTRICAL PERFORMANCE OF CONDUCTING POLYPYRROLES

Polypyrrole films, typically 0. 2 mm thick, were prepared by electrodeposition with p toluene sulphonate as dopant anions. Conductivities of up to 340 S Cm** minus **1 were found, comparing favourably with other cited examples. Conductivity along each sample was found to be much greater than across: such asymmetry may be exploitable. Electrodeposition temperatures (0 degree C) lead to higher conductivities than at 25 degree C. The structure was amorphous as indicated by X-ray diffraction, and the morphology was found to be nodular by using optical and scanning electron microscopy. Films were found to be quite strong and tough, although some reduction in mechanical performance was found after ageing in air. Fracture surfaces of tensile test pieces suggest a layered structure, with little evidence for viscous deformation being evident.