Abstract: In order to improve the flame-retardant properties of polyurethane insulation materials, the polyurethane material was modified based on the high-efficiency of PFR and the non-toxicity of EG. Comparisons were made between the modified polyurethane insulation material and conventional polyurethane material in flame-retardant properties such as heat release rate, thermal weight, oxygen index and other parameters. The results show that the application of phosphorus flame retardant greatly reduces the heat release rate peak of polyurethane insulation materials, defers the ignition time and the peak time of heat release rate, and improves the quality retention rate of polyurethane materials, that the flame retardant effect is best when the mass ratio of three (1,3-two isopropyl chloride) phosphate(TDCPP) and Four(2-chloro ethyl) two diethyl ether two phosphate ester(CR-505) is 1∶1, that when PFR and EG are used together, the synergistic effect is added, and the flame retardant effect of the polyurethane insulating materials are further improved, that compared with the conventional polyurethane insulation material, the thermal stability of modified polyurethane insulation material is better, and that the oxygen index of polyurethane insulation material modified collaboratively by PFR and EG is more than 30%, which means it is difficult to burn.

Key words: polyurethane insulation material, phosphorus flame retardant(PFR), expandable graphite(EG), collaborative modification, flame-retardant properties