Mechanochemical actuators fabricated from polypyrrole films with anisotropy

Abstract

Polypyrrole (PPy) pipe was electrochemically polymerized in a Teflon slender pipe. It was found that a PPy film cut from the PPy pipe has anisotropy in conductivity as well as in morphology, and bends and reverts in a regular direction during redox cycles. That is, the anisotropic PPy film can be used as an actuator. We have investigated the bending behavior of the PPy actuator in various electrolytes and have found that incorporation of cations into PPy upon reduction plays a key role in the bending behavior. A mechanism of the bending behavior based on the cations transport as well as the anisotropic volume change upon doping is proposed.