Abstract
Dielectric elastomer actuators (DEAs) are a type of versatile transducers that are lightweight and energy efficient. They hold great promise for soft actuators such as those resembling muscles. DEAs consists of a thin
elastomer sheet sandwiched between two compliant electrodes. In the actuation mode, applying a voltage on
the electrodes triggers the attractive Coulombic force between opposing charges. The Coulombic force compresses the elastomer, which causes it to expand perpendicular to the applied electric field. In this paper,
various polymer mixtures and a curing agent of polydimethylsiloxane (PDMS), are used to optimize the actuation performance of DEAs. To understand the mechanical properties of the material, a series of single pull tensile tests is conducted. Stress softening in tensile tests of PDMS depends on the mixing ratio of the base polymer and the curing agent. Increasing the polymer ratio in PDMS yields a softer material. We expect that softer
materials have a better performance for DEAs since they require a lower voltage for the actuation. Furthermore, we also compute the nonlinear mechanical Mooney-Rivlin, second-order Ogden, and Neo-Hookean models from the stress-strain data. Although all models agree fairly well in the lower-strain region, the second-order Ogden model is preferable in the strain-hardening region.
