Synergistic Effects of a Novel Phosphorus-Silicon Flame Retardant with Ammonium Polyphosphate in Flame Retarded Polypropylene

A novel phosphorus-silicon flame retardant(EMPZR) and ammonium polyphosphate(APP) have been used to improve flame retardancy of polypropylene(PP).When the mass ratio of APP/EMPZR was 20/15,the LOI value of flame retardant PP composites was increased to 28 %,and the burning grading was reached to UL-94 V-2;polypropylene,the tensile,bending and impact strength of composites were no less than plain polypropylene.Its char residue was 21.20 % at 600 ℃ which showed by the thermogravimetry analysis(TGA) and a good synergistic effects of EMPZR with APP in the halogen-free flame retardant PP composites was proved by scanning electron microscope(SEM) and FT-IR.