Contribution of conformational change of polymer structure to electrochemomechanical deformation based on polyaniline

The pH dependencies of electrochemomechanical deformation (ECMD) including the cyclic voltammetry and the expansion ratio in conducting polymers, polyaniline (PANI), and poly(o-methoxyaniline) film were studied to elucidate the mechanisms. It was found that the ECMD is governed by the conformational change of polymer structure as well as the insertion of bulky ions in the manner of comparable magnitude. Expansion ratios > 20% in the ECMD were demonstrated for the thickness direction of PANI film. The results suggest that the magnitude of ECMD can be improved by choosing the preparation method of films.