Soft Electromechanical Elastomers Impervious to Instability

TL;DR

This paper presents a theoretical analysis showing that certain soft dielectric elastomers can become resistant to common failure modes under specific electric and mechanical loads, enhancing their reliability for various applications.

Contribution

Using a group-theory based approach, the authors derive a closed-form solution revealing a regime where elastomers are impervious to instability prior to dielectric breakdown.

Findings

Elastomers become impervious to Treloar-Kearsley instability at a critical electric field.

A regime of loads where elastomers are invulnerable to failure modes is identified.

Theoretical framework predicts failure thresholds before dielectric breakdown.

Abstract

Soft dielectric elastomers that can exhibit extremely large deformations under the action of an electric field enable applications such as soft robotics, biomedical devices, energy harvesting among others. A key impediment in the use of dielectric elastomers is failure through instability mechanisms or dielectric breakdown. In this work, using a group-theory based approach, we provide a closed-form solution to the bifurcation problem of a paradigmatical elastomer actuator and discover an interesting result: at a critical electric field, the elastomer becomes impervious to Treloar-Kearsley instability. This limit is reached prior to the typical dielectric breakdown threshold. Our results thus establish a regime of electrical and mechanical loads where the dielectric elastomer is invulnerable to all common failure modes.