Development of a Soft Robotic Bending Actuator Based on a Novel Sulfonated Polyvinyl Chloride–Phosphotungstic Acid Ionic Polymer–Metal Composite (IPMC) Membrane

Abstract

This work presents the development of a cost-effective electric-stimulus-responsive bending actuator based on a sulfonated polyvinyl chloride (SPVC)–phosphotungstic acid (PTA) ionic polymer–metal composite (IPMC), using a simple solution-casting method followed by chemical reduction of platinum (Pt) ions as an electrode. The characterizations of the prepared IPMC were performed using Fourier-transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques, Thermogravimetric analysis (TGA), and Energy-dispersive X-ray (EDX) analysis. Excellent ion-exchange capacity (IEC) and proton conductivity (PC), with values of ca. 1.98 meq·g−1and ca. 1.6 mS·cm−1, respectively, were observed. The water uptake (WU) and water loss (WL) capacities of the IPMC membranes were measured at 25 °C, and found to have maxima of ca. 48% for 10 h, and ca. 36% at 6 V DC for almost 9 min, respectively. To analyze the actuation performance of the developed membrane, tip displacement and actuation force measurements were conducted. Tip displacement was found to be ca. 15.1 mm, whereas bending actuation was found to be 0.242 mN at 4 V DC. The moderate water loss, good proton conductivity (PC), high thermal stability, and good electrochemical properties of the developed IPMC membrane actuator position it as a cost-effective alternative to highly expensive conventional perfluorinated polymer-based actuators.

Review on the use of impedance spectroscopy for IPMC-like devices: application, models, and a new approach to data treatment

“…Even in the most recent works, using EIS to calculate IPMC ionic conductivity is common. No further information is given throughout the data obtained independently if the application is an actuator [96][97][98][99][100][101][102] or an energy harvesting device. 103 Thus, in the following sections, we will present some other features for IPMC devices using EIS.…”

“…Nafion/Ppy-CB-MWCNT 74 Actuator 74,89,[146][147][148][149][150][151]153,155 H + , 149,150 Na + 75 Nafion/AuNP-PAH 75 Sensoring 75,105,106,152 Li + 74,89,105,106,147,148,151-153,155 Nafion-TiO 2 /Pt 89 Transducer 145 EMIM 105,106 Nafion/RuO 2 -EMI-TF 105,106 EMI-TF/Li + 145 Nafion/RuO 2 145 EMI + 146 Nafion/carbon-LI 146 Nafion/CNT/Pd 147,148 Nafion/GO/Pt 149 MCNTs-Nafion/Pt 150 Nafion/Pt-EGaIn 151 Nafion/Pt (engineered) 152 Nafion/Pt-PVP@AgNPs 153 Nafion/Ppy-Pt 155 Nonconventional PVDF-PVP-PSSA/Pt 73 Actuator 73,84,85,102,128,154,156,[158][159][160][161][162][163] H + 73,84,102,128,154,156,158,161-163 Flemion/Au 132 Sensoring 132 Li + 73,132,157 PVA/rGO-PANI …”

A comprehensive survey of ionic polymer metal composite transducers: preparation, performance optimization and applications

“…Besides, thorium (IV) phosphate (ThP), sulfonated poly(arylene ether ketone) (SPAEK), sulfonated polyether ether ketone (SPEEK), sulfonated polyvinyl chloride (SPVC) Kraton, etc. [59][60][61][62][63][64] are also candidates to substitute Nafion.…”

Synthesis, Characterization and Fabrication of Copper Nanoparticles Embedded Non-Perfluorintaed Kraton Based Ionic Polymer Metal Composite (IPMC) Actuator

“…Polymer-based actuators are one of the most important actuation materials that produce various mechanical responses using numerous external stimuli. One of the common stimulators is electrical energy, which converts electrical energy to mechanical energy [1][2][3]. A lot of polymeric materials are electrically responsive, including ionic polymer gels (IPGs), ionic polymer metal composites (IPMCs), dielectric elastomers (DEMs), conductive polymers (CPs), and piezoelectric polymers (PEPs), which are widely used in making micro/soft robots and biomimetic artificial muscles [4][5][6][7][8].…”