The synthesis of a novel flame retardant and its synergistic efficiency in polypropylene/ammonium polyphosphate system

A novel flame retardant, Si-E, was synthesized and characterized by nuclear magnetic resonance (NMR). The flame retardancy of Si-E in polypropylene/ammonium polyphosphate (PP/APP) composites was studied by limited oxygen index (LOI) and cone calorimeter (CONE). The influence of the flame retardant additives on the thermal degradation process in PP composites was ascertained by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA) and the char morphology was examined by scanning electron microscopy (SEM). The addition of Si-E to PP/APP composites can simultaneously improve the flame retardancy and improve the impact strength, due to good compatibility and toughness of Si-E in PP/APP. The CONE test also showed that the heat release rate and smoke production rate were significantly reduced in PP/APP/Si-E composites. Copyright (C) 2011 John Wiley & Sons, Ltd.