Flame Retardancy and Thermal Decomposition Kinetics of BDP Flame-Retarded PC/ABS and Its Nanocomposites

摘要

The polycarbonate(PC)/polyacrylonitrile-butadiene-styrene(ABS),PC/ABS/organic montmorillonite(OMMT) and PC/ABS/organic-modified SiO2 composites flame retarded by bisphenol A di(phosphate phenyl ester)(BDP) were prepared by extrusion and granulation of twin-screw extruder. By means of TG, their thermal decomposition kinetic behaviors in nitrogen atmosphere with a certain heating rate were studied. Therefore, the relationship between flame retardant property and thermal decomposition was researched. It has been found that the apparent activation energy of the BDP flame-retarded PC/ABS/OMMT and PC/ABS/SiO2 nancomposites was lower that of the BDP flame-retarded PC/ABS before 8% mass loss. However, the apparent activation energy of BDP flame-retarded PC/ABS/OMMT and PC/ABS/SiO2 nancomposites was more than that of BDP flame-retarded PC/ABS after 8% mass loss. The average activation energy of two nanocomposites were 139.39kJ·mol-1 and 144.17 kJ·mol-1 within 5%～75% mass loss respectively, and they were all greater than that of BDP flame-retarded PC/ABS(104.87 kJ·mol-1). It was proved that with the OMMT and SiO2 added, the thermal decomposition rate of two nanocomposites decreased and the thermal stability increased because of the Flame Retardant Synergism of BDP and OMMT or SiO2. This conclusion was consistent with the test results of Limiting oxygen index(LOI), UL94V flame retardancy.