Wrinkling stability in soft dielectric elastomers: The role of strain stiffening and stretch-dependent permittivity

Abstract

Dielectric elastomers (DEs) offer exceptional performance in electromechanical energy conversion, positioning them as key components in next-generation actuators and in the efficient capture of mechanical energy from renewable sources. The performance of these elastomers is significantly influenced by their electrical breakdown strength, a critical parameter that determines the maximum electric field the material can withstand before failure. The influence of stretch-dependent permittivity and strain stiffening on the electrical breakdown strength of materials is crucial for enhancing the understanding of their electromechanical behavior under various loading conditions. In this study, we conducted a comprehensive investigation into the influence of stretch-dependent permittivity and strain stiffening, on the electromechanical breakdown strength of DE membranes. To provide a comprehensive analysis, we implement the different models of permittivity variation with stretch, including constant, linear, and nonlinear scenarios. The results of this study demonstrate that a nonlinear variation in dielectric permittivity offers a more accurate representation of the experimental electromechanical behavior. Moreover, under a constant applied electric field, an increase in the strain stiffening parameter notably reduces the taut domains of the DE membranes, attributed to the enhanced resistance to deformation at higher stiffening levels. The insights gained from this study are crucial to optimizing the design and performance of smart membrane systems in advanced engineering applications. © 2025 Elsevier Ltd