Processing optimization: A way to improve the ionic conductivity and dielectric loss of electroactive polymers

ABSTRACT Electro‐active polymers (EAPs) such as P(VDF‐TrFE‐CTFE) are greatly promising in the field of flexible sensors and actuators, but their low dielectric strength driven by ionic conductivity is a main concern for achieving high electrostrictive performance. It is well known that there is a quadratic dependence of the strain response and mechanical energy density on the applied electric field. This dependence highlights the importance of improving the electrical breakdown EAPs while reducing the dielectric losses. This article demonstrates that it is possible to dramatically increase the electrical breakdown and decrease the dielectric losses by controlling processing parameters of the polymer synthesis and fabrication procedure. As a result, an enhancement of around 70% is achieved in both the strain and blocking force. The effects on the dielectric losses of the polymer crystallinity, molecular weight, solvent purity, and crystallization temperature are also investigated. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 1164–1173 The interesting and highly promising features of electro‐active polymers in the field of actuators, such as P(VDF‐TrFE‐CTFE), are severely limited by their low electrical strength. The quadratic dependence of Applied‐Electric Field on Field‐Induced Strain highlights the importance of improving electrical breakdown of electro‐active polymers. Through optimization of polymer synthesis and polymer solution‐processing, control of polymer electrical strength is possible. It will be demonstrated in this work that a huge improvement in electrical strength could be achieved, showing high potential of the proposed material in actuation applications.