An electro-mechanical model of ionic polymer metal composites

Ionic polymer-metal composites (IPMC) is a new type electroactive polymer material, it has broad application prospects. In order to effectively describe the deformation law of IPMC, an electric-mechanical actuator model for IPMC was proposed in this paper. In this model, force balance equation of hydrated cation was established, and the concentration of water molecules as well as the water content distribution was calculated based on the concentration of hydrated cation distribution and diffusion of water molecules; the relationship between water content and strain was determined by experiments; then the strain distribution along the thickness and the corresponding output displacement of IPMC sample were obtained. The method is suitable for different shapes of IPMC actuators. The results from the simulation and experiment verified that the electric-mechanical actuator model in this paper well expressed the characteristics of the IPMC actuators under a step DC voltage, which proved that the method is correct and feasible.