Enhancing Dielectric Elastomer Driven Deformation Through Multifunctional Chemical Crosslinkers

ABSTRACT With the rapid development of flexible wearable devices and transducers, plenty of studies have been conducted in recent years on dielectric elastomers (DEs) for various applications due to their significant deformation ability, high energy conversion efficiency, and lightweight. However, DEs usually need pre‐stretching to enhance electric breakdown strengths and produce large deformation, increasing the complexity of the driving structures and limiting their applications. In this work, the electromechanical properties of elastomers chemically crosslinked by crosslinking agents with different functionalities are investigated. The Young's modulus can be increased as the content of the trifunctional crosslinking agent increases, leading to a remarkable enhancement of electrical breakdown strength and subsequent driving deformation. Specifically, PT4.5 achieves a maximum driving deformation of 34.2% at 46 kV mm −1 without pre‐stretching, increasing by 75% compared with PT0, which is crosslinked only by bifunctional crosslinking agent. Consequently, the energy density reaches 0.034 MJ m −3 , which is 4.2 times higher than mammalian skeletal muscle (0.008 MJ m −3 ). These findings propose a practical and simple strategy to improving breakdown strength and electrically driven deformation without the need for pre‐stretching.