Improved electro-actuated property of polydimethylsiloxane-based dielectric elastomer by designing a Bi-network structure

Dielectric elastomers (DEs) have a great potential in applications as smart materials such as artificial muscles and flexible robotics, due to their advantages of large deformation, good flexibility and fast actuation response. However, the excellent electro-actuation performance of DE materials is always achieved under high electric fields, which limits their widespread application. Herein, the synthesized acrylate-based copolymer E8G2 (the molar ratio between 2-ethylhexyl acrylate and glycidyl methacrylate is 8:2) was incorporated into the polydimethylsiloxane (PDMS) matrix by solution mixing and compression molding to prepared a series of bi-network DE composites. The design of the all-organic bi-network structure not only regulates the dielectric-flexibility of E8G2/PDMS composites synchronously but also relieves the problem of plasticizer exudation. The E8G2/PDMS composites achieved a remarkable electro-actuated strain of 43.86 % at 50 V/μm, which is improved by 431.08 % compared with pure PDMS (6.95 %). Consequently, this study provides a promising approach for the preparation of advanced DE composites with outstanding electro-actuated performance in low-field driving applications.