TERNARY FLAME RETARDANT SYSTEM OF AMMONIUM POLYPHOSPHATE-DIATOMITE-NANO-SiO2 AND ITS APPLICATION IN FIBROUS MATERIALS

Ternary composite flame retardantswereprepared via in-situpolymerization of ammonium polyphosphate (APP)-diatomite (DE)-nano-SiO2 and were used for the improvement of flame retardance and smoke suppression of paper fibrous materials. Thermogravimetric analysis (TGA), limiting oxygen index (LOT), cone calorimeter test (CCT) and scanning electron microscope (SEM)were used to evaluate the thermal stability of the composite flame retardants andthe flame retardance and smoke suppression of paper loading the flame retardants. Results show that the LOI value of paper loading 20% APP-DE-2%nano-SiO2 reached 26.7%, which was higher than that of paper loading the same dose of the ternary compositefillers. The addition of nano-SiO2 reduced the mass loss of the composite filler at high temperature and promoted the condensed phase flame retardation of the paper loading the composite filler. The existence of nano-SiO2 reduced the heat release rate (HRR) and rate of smoke release (RSR) of paper sample, thereby improving the flame retardance and smoke suppression of fibrous materials.