Enhancing Mechanical and Actuation Properties of Silicone Dielectric Elastomers by Polarizable Small Molecule Doping

Dielectric elastomers, with their high deformability, high energy density, and flexibility, are ideal candidates for applications such as artificial muscles, flexible robots, and wearable devices. However, high drive voltages and complex preparation processes have limited their development for large-scale practical applications. In this work, we used a simple reaction blending method to introduce acrylonitrile with high polarizability and 3,7-dimethyl-6-octenitrile into silicone rubber, respectively, to prepare dielectric elastomers with excellent mechanical and electro-mechanical properties. Experimental results show that both mechanical and electro-mechanical properties are synergistically enhanced, with the elastic modulus reduced to 0.53 MPa, and the maximum electro-mechanical sensitivity reaching 17.36 times that of unmodified silicone rubber. Under an electric field strength of 35.3 kV/mm, the maximum driving strain of the unstressed film can reach 13.19%, which is 599% that of ordinary silicone rubber. This work provides new insights for the development of novel dielectric elastomers suitable for low drive voltages, low elastic moduli, and high drive strains.