Electro-mechanical properties and electrostriction response of a rubbery polymer for EAP applications

The mechanical response of a widely used electro-active polymer (EAP) material, and the sensitivity of this response to imposed strain rate, are measured by performing tension and compression tests at constant strain rate as well as relaxation experiments. Simple actuators are constructed and used to determine the sensitivity of the material’s relative dielectric permittivity to excitation frequency and imposed equibiaxial strain. Actuators are subjected to both a monotonic, slowly increasing electrical excitation and to a more rapid oscillating electric field; the differences in the resulting actuation strains reveal the importance of the material’s viscosity in its performance as an actuator.