High performance electromechanical actuators based on ionic liquid/poly(vinylidene fluoride)

Due to the increasing need of low voltage actuators, independent from electrochemical processes, electroactive actuators based on poly(vinylidene fluoride) composites with 10, 25 and 40% of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C(2)mim] [NTf2], ionic liquid are prepared by solvent casting and melting. We show that the charge structure of [C(2)mirn] [NTf2] induces the complete piezoelectric beta-phase crystallization of the PVDF within the composite and decreases its crystallinity fraction significantly. [C(2)mim] [NTf2] also works as a plasticizer of PVDF, reducing the elastic modulus down to 12% of the initial value. Moreover, the composites show significant displacement and bending under applied voltages of 2, 5 and 10 Vpp. The displacement and bending of the composite membranes are also evaluated as a function of [C(2)mim] [NTf2] content and sample thickness. Increasing amounts of ionic liquid result in larger deformations independently of the applied voltage. (C) 2015 Elsevier Ltd. All rights reserved.