Electroactive behavior of poly(acrylic acid) grafted poly(vinyl alcohol) samples, their synthesis usinga Ce(IV) glucose redox system and their characterization

Abstract

Grafted copolymers of poly(acrylic acid) (PAA) and poly(vinyl alcohol) (PVA) were prepared usinga Ce(IV) glucose redox initiator by free radical polymerization. Three grafted copolymershaving 20%, 50% and 80% grafting were selected for this study. Thus-modifiedpolymer was characterized by means of Fourier transform infrared spectra,1H NMR, gel permeation chromatography, thermogravimetric analysis and universal testingmachine approaches. The membranes were prepared by a solution casting method, wherethe cross-linking process was performed through the in situ addition of glutaraldehydeand hydrochloric acid as the cross-linking agent and catalyst respectively. Thefollowing four membranes were prepared: (i) pure PVA; (ii) 20% grafted PVA;(iii) 50% grafted PVA; (iv) 80% grafted PVA. The membranes obtained wereemployed in the electroactive behavior study under a DC electric stimulus in differentconcentrations of electrolyte. The equilibrium bending angles (EBA) of thesepolymers were studied with respect to time, poly(acrylic acid) content, electricvoltage applied across the polymer and ionic strength of the electrolyte used.Experimental results show stable reversibility of the bending behavior of thesepolymers under an applied DC electric field. The EBA increased with increase inthe applied electric voltage and poly(acrylic acid) content within the polymer.