Experimental and theoretical investigation of the interaction of sulfonated graphene oxide with polyvinylalcohol/poly (4-styrenesulfonic) complex

Abstract The effect of sulfonated graphene oxide (SGO) on the interaction mechanism of polyvinyl alcohol and poly (4-styrene sulfonic acid) (PVA/PSS) matrix is investigated in this paper. Pure PVA/PSS, PVA/PSS/graphene oxide (GO) and PVA/PSS/SGO nanocomposites are prepared by the freeze-thaw method. The glutaraldehyde (GLA) is used as a crosslinking agent to improve the stability of the materials. The sulfonation of GO is confirmed by the Fourier transform infrared spectroscopy (FTIR) and X-ray fluorescence spectrometry (XRF) analyses. The fully exfoliation of GO is recognized using a transmission electronic microscopy (TEM). All the nanocomposites are characterized using FTIR, UV–Vis spectroscopy and scanning electron microscopy (SEM). A theoretical molecular simulation of the nanocomposites systems is performed to elucidate the different energies associated with the interfacial interactions. A strong interaction energy is determined due to the presence of different functional groups within the systems. The hydrogen bonding of the OH, COOH, SO 3 H and C-O-C groups show a E H-bond energy for the PVA/PSS/SGO system (−735.39 kcal/mol) which is higher than the corresponding of PVA/PSS/GO (−686.86 kcal/mol). The effect of the sulfonated group is more significant than that of the carboxylic group, due to both the higher polarity and higher electronegativity of the sulfonic acid group.