Physiochemical Modification of Graphene Nanosheets to tailor Electrical Properties of Graphene based PMMA Composites

Abstract

In the present work, a series of modified reduced graphene oxide (m-rGO) based poly methyl methacrylate (PMMA) composite by solution mixing method using chloroform as solvent have been synthesized. Here, reduced graphene oxide (rGO) has been modified by using Friedal-Craft acylation reaction. For this purpose, 4-bromobenzoic acid was used as a reagent in the above mentioned reaction to introduce an acyl group at the surface of rGO, which may increase the homogeneity of the synthesized composites of m-rGO and PMMA (m-rGO/PMMA). Series of composites having different wt. % of filler (m-rGO) was prepared. FTIR and UV-Vis spectroscopic techniques were employed for confirmation of the synthesis of GO and rGO and modification of the rGO. Significant improvement in electrical properties has been observed because of the surface modification of the rGO. An interesting frequency dependence relationship between conductivity and dielectric constant has been obtained. A lower percolation threshold was observed for these nanocomposites because of enhanced interfacial interaction of m-rGO with PMMA. Above mentioned results encourage the modification of the rGO for its incorporation in PMMA for composite formation.