Ionic polymer-metal composite mechanoelectric transduction: Effect of impedance

Abstract

Ionic polymer-metal composites (IPMCs) are commonly used as soft actuators due to their electromechanical response. However, the reverse phenomenon, i.e. IPMC's ability to generate charge on application of mechanical strain (mechanoelectric response), is not very well understood. The concept of mechanoelectric transduction and its dependence on complex IPMC architecture comprising of electrode, polymer and composite layer is illustrated with a phenomenological model. The impedance model takes into account the charge transport inside the polymer and layer properties in terms of their impedances. The model lucidly indicates the significance of capacitance in IPMC transduction. The impedance model is used for studying IPMC step and frequency response and the effect of IPMC capacitance on its application as energy harvester. © 2012 Taylor and Francis Group, LLC.