Effect of anion type in the performance of ionic liquid/poly(vinylidene fluoride) electromechanical actuators

Abstract

Low voltage actuators based on poly(vinylidene fluoride) (PVDF) with 10, 25 and 40 % 1-hexyl-3-methylimidazolium chloride ([C6mim][Cl]) and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C6mim][NTf2]) are prepared by solvent casting in order to evaluate the effect of anion size in the bending properties. Independently of the ionic liquid type and content, its presence leads to the crystallization of PVDF in the phase. The addition of ionic liquid into the polymer matrix decreases significantly its degree of crystallinity and the elastic modulus. It is also confirmed the good miscibility between PVDF and IL, determined by the interaction of the CF2 groups from the PVDF chains with the imidazolium ring in the ionic liquid (IL). The AC conductivity of the composites depends both on the amount of ionic liquid content and anion size. The bending movement of the IL/PVDF composites is correlated to their degree of crystallinity, mechanical properties and ionic conductivity value and the best value of bending response (0.53 %) being found for IL/PVDF composite with 40 wt% of [C6mim][Cl] at an applied voltage of 10 volts square signal.

Physico‐Chemical Characterizations of Poly(vinylidene fluoride)/Cu3(BTC)2 Composite Membranes Prepared by In Situ Crystal Growth

“…S3. The results evidenced a relative similar macroporous feature for both membranes with a pore mean diameter of 28 respectively. They are consistent with the corresponding SEM images (Figs.…”

“…The choice of PVDF was encouraged by its ability to form homogenous solution with metallic salts. In addition, thanks to the outstanding electroactive properties of its β ‐phase, PVDF and its membranes are important materials with extensively technological applications such as membrane distillation sensors , lithium‐ion battery , energy harvesting , and actuators .…”

Integration of PDA Chemistry and Surface‐Initiated ATRP to Prepare Poly(methyl methacrylate)‐Grafted Carbon Nanotubes and Its Effect on Poly(vinylidene fluoride)–Carbon Nanotube Composite Properties

“…In these phases, the β‐ and γ‐phases are the most electrically active due to the high dipole moment within the unit cell. Therefore, promoting the formation of β‐ and γ‐phases in PVDF‐based composites has become an ongoing pursuit due to their extensive applications in sensors and actuators . For example, Dias et al used an ionic liquid (IL) to compound with PVDF and its copolymers.…”

Degree of Crystallinity and Phase Fraction of Polyvinylidene Fluoride Nanocomposites Containing Ionic Liquid and Graphene/Carbon Nanotube

“…In general, using EMI‐BF 4 as an IL decreases the . This could be attributed to the presence of many small spherulites and the strong electrostatic interactions between ions and the dipole moments in the PVDF monomers which affects polymer crystallization kinetics . Positive and negative ions in the EMI‐BF 4 act as nucleation agents, leading to a high density of nuclei that confines the free growth of spherulites.…”