1:45 PM - 2:00 PM
▲ [21p-A301-4] Enhancement in energy density of electroactive polymer-based wearable devices using silicone rubber and carbon nanotube based composite dielectric film
Keywords:Electroactive polymers, Energy harvesting, Actuators and sensors
Electroactive polymers (EAP) can convert mechanical energy into electrical energy and vice versa making them suitable for wearable applications like generators, actuators, and sensors. However, currently utilized EAPs exhibit low energy density, which limits its widespread applications. In generator and actuator mode total available energy density is being controlled by four instabilities such as mechanical failure of the film, failure due to electrical breakdown, pull-in instability, and loss of stress. For the safe operation of EAP-based generators and actuators, available energy density is calculated by the area enclosed by all these four instabilities. Perlin et. al. reported the energy density of acrylic-based electroactive polymers equivalent to 0.4 J/g, which was later enhanced up 0.6 to 0.7 J/g for silicone-based polymers.In this work, uniaxial tensile measurement was performed on carbon nanotube (CNT) and silicone mixed composite films for three consecutive cycles. Later first stretching cycle of stress-strain curve was used for fitting the experimental data with available theoretical modeling for the rubbery materials and further fitting parameters were calculated. All nonlinear equations involved in four instabilities were solved by putting the value of constraints further area enclosed by all four instabilities was calculated and It was found that energy density is directly proportional to the dielectric constant and CNT based fillers improved the dielectric constant of film consequently enhancement in the energy density. Our results reveal that the composite film used for the present investigation exhibited a comparatively higher value of energy density which was equivalent to 1 joule/gram suggesting that such films can improve the performance of generators and actuators. In the case of sensor mode, energy density can be calculated by area under the stress-strain curve only because the sensor does not involve high actuation electric field.