Electrical conductivity of elongated polypyrrole film

Abstract

The mechanical and electrical properties of elongated polypyrrole film have been investigated. The maximum elongation ratio of electrochemically prepared polypyrrole film increased on decreasing the elongation speed and reached 0.55. The simultaneous measurement of tensile stress and electrical resistance of the film during elongation has also been carried out. The approximately constant resistivity of the film by weight or volume was observed during measurement at slow elongation speeds; this provides evidence that the polypyrrole is a low-dimensional conductor. The electrical conductivity of the elongated and relaxed films increased in proportion to the square of the elongation ratio. The films with an elongation ratio of over 0.25 exhibited anisotropy in the conductivity.