Synergistic Effect Of Strontium Stannate/Ammonium Polyphosphate On Flame Retardance Of Polyurethane Foam

Polyurethane foam is a common polymer material,which has many advantages,such as low density,high resilience,low cost,and easy industrial preparation.And it has been widely used in many industrial and living fields,such as building insulation,chemical materials,civil aviation aircraft seating and so on.However,because the limiting oxygen index(LOI)of polyurethane foam is only 18%?19%,it is very easy to cause fire before the flame retardant of polyurethane foam is improved.Therefore,the further application of polyurethane foam is restricted,so it is necessary to study the flame retardant modification of polyurethane foam.On the basis of the requirements of green environmental protection and enhancing flame retardancy,flame retarded polyurethane foam was prepared by SrSnO3/APP.The flame retardant properties of modified polyurethane foam were characterized by using X ray diffractometer,limiting oxygen index instrument,cone calorimeter and smoke toxicity tester.The results showed that the synergistic effect of strontium stannate and ammonium polyphosphate could effectively enhance the flame retardancy of polyurethane foam,and the LOI of the flame retardant polyurethane foam increased by 6.2%,the combustion level increased to FH-1,the heat release rate decreased by 98.7kW/m2,the total heat release decreased by 6.5MJ/m2,and the carbon residue increased from 17%to 35%.In addition,the IPDT increased from 639? to 1140? and the thermal stability of the modified foam was improved significantly.At the same time,the addition of synergistic flame retardant can effectively inhibit the generation of a large amount of flue gas due to the addition of ammonium polyphosphate.In conclusion,the flame retardant property of the foam is the best when SrSnO3 and APP are added 20wt%.