Towards a physics-based modelling of the electro-mechanical coupling in EAPs

TL;DR

This paper compares three electromechanical models of electro-active polymers (EAPs) to better understand their behavior under homogeneous deformation, emphasizing the importance of microstructure in accurate modeling.

Contribution

It introduces and compares three different models, including microstructural approaches, to improve the understanding of EAPs' electromechanical behavior.

Findings

Differences in model predictions highlight the need for microstructural considerations.

Micro-sphere technique effectively links microscopic and macroscopic responses.

Model comparisons suggest directions for more detailed EAP behavior studies.

Abstract

Due to the increasing number of industrial applications of electro-active polymers (EAPs), there is a growing need for electromechanical models which accurately capture their behavior. To this end, we compare the predicted behavior of EAPs undergoing homogenous deformations according to three electromechanical models. The first model is a continuum based model composed of the mechanical Gent model and a linear relationship between the electric field and the polarization. The electrical and the mechanical responses according to the second model are based on the polymer microstructure, whereas the third model incorporates a neo-Hookean mechanical response and a microstructural based long-chains model for the electrical behavior. In the microstructural motivated models the integration from the microscopic to the macroscopic levels is accomplished by the micro-sphere technique. Four types of homogeneous boundary conditions are considered and the behaviors determined according to the three models are compared. The differences between the predictions of the models are discussed, highlighting the need for an in-depth investigation of the relations between the structure and the behaviors of the EAPs at microscopic level and their overall macroscopic response.