Thermal degradation and flame retardancy of polypropylene/C60 nanocomposites

Nanocomposites based on polypropylene (PP) and fullerene C60 (in the range of 0.5–2 wt%) were prepared by melt compounding. It was observed that C60 could not only significantly enhance the thermal stability in nitrogen but also considerably delay the oxidation decomposition in air of polypropylene. Unexpectedly, the incorporation of C60 greatly reduced the heat release rate of PP and resulted in a longer time to ignition. And the free radicals-trapping mechanism of C60 was proposed for explaining the enhanced thermal properties and improved flame retardancy of PP. Therefore, C60 will be an effective flame retardant like carbon nanotubes and clay for PP.