Mechanical characterization of free-standing polypyrrole film

Free-standing polypyrrole films, neutral or doped with ClO4−, have been mechanically characterized. Their elasticity of both dry and wet states was characterized by mean of the Young's modulus. In addition, the Young's modulus was calculated as a function of the film oxidation deep by “in situ” polarization at different potentials ranging from − 0.6 up to 0.8 V. The samples also were characterized under oxidation and reduction by reverse constant currents. When the films were submitted to a constant stretching force the length variations were obtained. At a constant length of the sample the electro-chemo-mechanical force developed by the redox processes was obtained. As predicted by the ESCR model lineal variations of both, length and force, as a function of the consumed charge were obtained.