A thermodynamic model for ionic polymer–metal composites and finite volume-finite element solution

The transient electromechanical response of an ionic polymer–metal composite (IPMC) is modeled within a thermodynamic framework using the Euler–Bernoulli beam theory coupled with electrostatically driven diffusion to account for the flow of the ionic fluid phase. A finite volume-finite element model to handle general electromechanical load conditions has been developed based on the new beam theory. The model has been shown to simulate various electromechanical responses of IPMC strips including initial overshoot followed by a back-relaxation, and anode and cathode side equilibrium configurations. Water–polymer interaction has been shown to be sufficient to capture these responses. The model can be used in both actuator and sensor applications of IPMC beams.