A large-strain and high actuation stability dielectric elastomer with a designed molecular-level hybridized network structure

As a new type of electroactive material, the dielectric elastomer (DE) is widely used in applications such as actuators and sensors. However, since DEs typically have a low dielectric constant ( ε r ) and high stiffness, the dielectric elastomer actuator (DEA) requires a high driving field strength to achieve high performance. In this work, a new kind of DE with a molecular-level hybridized network structure (silicone rubber-polyurethane-acrylate) was designed to obtain high driving performance. The introduction of polar carbamate groups was intended to obtain a high ε r , and the formation of a linear polymer chain by modulating the ratio of hydroxyl to isocyanate groups resulted in an adjustable Young's modulus ( Y ). Finally, the prepared new DE-Acry-PU3 exhibited a maximum actuation strain of 28 % at a very low driving field strength of 15 kV/mm. In addition, Acry-PU3 has good driving durability and low loss, and the linear DEA based on Acry-PU3 can achieve a large displacement of 0.55 mm and a high output force of 92 mN/g at a low driving field strength of 15 kV/mm.