Experimental study on permittivity of acrylic dielectric elastomer

This paper reports the experimental study on the frequency and stretch dependency of permittivity of a commercially available acrylic dielectric elastomer (VHB 4910) film. The procedure for preparing samples with different thickness using in-house developed uniaxially stretching device is described. Copper tapes are implanted on two opposite sides of a stretched elastomer film and permittivity of this material is estimated from measured capacitance using LCR meter. Variations of permittivity of this material with different pre-strain value and with different applied voltage frequency are studied. Results show that the permittivity of the material decreases with increasing frequency and increasing pre-strain value. The study would be useful for estimation of frequency and strain dependent actuation pressure of a dielectric elastomer actuator.