Influence of organophosphorous silica precursor on the thermal and fire behaviour of a PA66/PA6 copolymer

An organophosphorus silica filler was generated in situ the molten PA66 copolymer (Cop-PA) during extrusion process without adding solvents. Nanocomposites synthesis is based on hydrolysis-condensation reactions of diethylphosphatoethyltriethoxysilane precursor (SiP). The thermal stability of Cop-PA/SiP nanocomposites and the major degradation products were studied by thermogravimetric analysis (TGA) and TGA coupled with Infrared spectrometry (TGA/FTIR). The Pyrolysis Combustion Flow Calorimeter (PCFC) and cone calorimeter were used to investigate the fire behaviour of the nanocomposites. Results showed a decrease by more than 50% of the peak of heat release rate (PHRR) and the formation of an expanded char layer with the addition of only 0.91wt% of silicon and 0.96wt% of phosphorus by this original route of fillers dispersion.