Impact and Fire Resistance Properties of Polypropylene Filled with Graphene/Mg(OH)2 Nanoparticles

Abstract

Nanocomposites made from graphene nanoplatelets (GN) and magnesium hydroxide (Mg(OH)2) based on polypropylene (PP) matrix were prepared via melt-mixing in an internal mixer, and followed by compression molding. The composition ratios of GN/Mg(OH)2 were varied by the GN from 0.5 to 1.5 wt.% and Mg(OH)2 from 5 to 15 wt.%. The impact mechanical property and fire resistance of PP nanocomposites were examined. The significance effects of GN and Mg(OH)2 loadings were determined via statistical analysis. The solely inclusion of GN had increased the impact strength and fire resistance of PP with the maximum level achieved at 1 wt.% GN. By adding Mg(OH)2 into GN filled PP nanocomposites, it showed a reduction in impact strength with the increase of fillers loading, whilst for fire resistance, the burning rates were the lowest at the composition ratios of 0.5/10 wt.% GN/Mg(OH)2 and 1/5 wt.% GN/Mg(OH)2. Statistical analysis proved the significant individual effect of GN and Mg(OH)2 loadings on both properties but insignificant interaction between both parameters (loadings of GN and Mg(OH)2). In the presence of Mg(OH)2, scanning electron microscope (SEM) micrograph showed a more porous microstructure of nanocomposites.