Novel ionic polymer–metal composite actuator based on sulfonated poly(1,4-phenylene ether-ether-sulfone) and polyvinylidene fluoride/sulfonated graphene oxide

In the present work, sulfonated graphene oxide and sulfonated poly(1,4-phenylene ether-ether-sulfone) were blended with polyvinylidene fluoride to create a novel ionic polymer–metal composite actuator with enhanced performance. An ionic polymer–metal composite membrane in the protonated form was prepared by casting a composite blend of sulfonated poly(1,4-phenylene ether-ether-sulfone), polyvinylidene fluoride and sulfonated graphene oxide onto a plating of platinum metal as the electrode. The degree of sulfonation of poly(1,4-phenylene ether-ether-sulfone) was characterized using ion-exchange capacity measurements. Energy dispersive X-ray and transmittance electron microscopy analyses were carried out to analyze the chemical composition and detailed structure. Deposition of the platinum electrode and the surface morphology of the proposed ionic polymer–metal composite actuator were assessed using scanning electron microscopy analysis. The electrical properties were measured using cyclic voltammetry, linear sweep voltammetry and proton conductivity. These measurements confirmed the better actuation performance of the fabricated ionic polymer–metal composite actuator compared to other expensive ionic polymer-based actuators, in terms of its high ion-exchange capacity, good proton conductivity, high current density and large bending deflection. The robust, flexible and mechanically strong membrane actuator, fabricated via the synergistic combination of sulfonated poly(1,4-phenylene ether-ether-sulfone), polyvinylidene fluoride and sulfonated graphene oxide, has considerable potential as an actuator material for robotic, bio-mimetic and other applications.