Facile synthesis of graphene sheets decorated nanoparticles and flammability of their polymer nanocomposites

Abstract

Novel and facile method was developed for the synthesis of graphene based flame retardant for acrylonitrile-butadiene-styrene. Graphene has been exfoliated by using ultrasonication in maleate diphosphate as dispersant. The exfoliation media produced high quality less defected graphene layers. The graphene wrapped with maleate diphosphate was decorated with TiO2 nanoparticles with an average size of 21 nm. Polymer composites of acrylonitrile-butadiene-styrene with maleate diphosphate, graphene wrapped with maleate diphosphate and decorated ones have been synthesized with solvent blending method. The flammability properties of the polymer nanocomposites were significantly reduced. The peak heat release rate (PHRR) and total heat release (THR) of the polymer nanocomposites contains nanoparticles decorated graphene achieved 49% reduction. Also, average mass loss rate was reduced by 50% and emission of carbon dioxide was suppressed by 37%. The rate of burning of nanocomposites was found to be 12 mm/min compared to virgin polymer of 42.5 mm/min achieved 71% reduction. The effect of combining graphene and the materials was investigated. The graphene wrapped with maleate diphosphate and maleate diphosphates itself were characterized using FTIR spectroscopy. The different polymer nanocomposite materials were characterized using thermal gravimetric analysis, UL94 flame chamber and cone calorimeter. The exfoliation of graphene was elucidated by Raman spectroscopy and XRD and the dispersion of graphene sheets in maleate diphosphate and their decorated composites with nanoparticle were characterized using transmission electron microscopy.