Enhancing the Performance of Dielectric Elastomer Actuators Through Chemical Modifications

Abstract

Current research on enhancing the performance of dielectric elastomer actuators (DEAs) primarily focuses on improving the properties of dielectric elastomers (DEs), including increasing the dielectric constant, reducing the elastic modulus, and minimizing dielectric losses. The commonly used composite filler method struggles to address the trade-off between high dielectric constant and low elastic modulus in DEs. In contrast, modifying the chemical structure by introducing polar groups into the DE polymer backbone can effectively increase the dielectric constant of DEs. Meanwhile, optimizing the degree of crosslinking and molecular weight can effectively reduce the elastic modulus of DEs. Currently, there remains a lack of systematic summarization regarding the chemical modification methods of DEs. This paper summarizes the actuation principles of DEs and introduces simple electromechanical modeling methods. It focuses on methods to enhance the dielectric constant of DEs through hydrosilylation, thiol-ene click reactions, and azide-alkyne click reactions, as well as methods to reduce the elastic modulus of DEs by improving the degree of crosslinking and molecular weight. Additionally, this study explores the current applications of DEAs in the fields of artificial muscles and soft robotics.