PDMS-Based Cone Type Dielectric Actuator Containing Double-Oxidized Nanosized Graphene-Encapsulated TiOz Nanowire at Low Applied Electric Field

초록

Dielectric elastomer actuators (DEAs) have versatile applications in soft robotics, medical devices, and environmental monitoring, making them a highly anticipated area for future applications. On the other hand, developing DEAs exhibiting high strain at low voltages remains a challenge. This paper reports a strategy for enhancing the actuating performance of polydimethylsiloxane (PDMS) at low voltages by preparing a hybrid filler comprised of TiO2 nanowires, polydopamine, and nano-sized reduced graphene oxide. This hybrid filler, merging the virtues of these three materials, was added at 15 phr, resulting in a 2.3-fold increase in the dielectric permittivity of PDMS while mitigating the increase in the loss tangent and enhancing efficiency. Actuators fabricated using this composite exhibited the highest deformation at 10 phr, reaching approximately 27.31% (at 28 V/μm), representing a remarkable 15.2-fold improvement compared to pure PDMS. Moreover, even at a low voltage of 1.6 V/μm, they displayed a substantial actuated strain of 2%. This novel strategy for manufacturing hybrid fillers is a promising example of enhancing the DEA performance, offering innovative solutions for future technological advancements.