Research Of Polyurethane-imide Foam Flame-retarded By Multiple Organic/inorganic Flame Retardants

Flame retarded rigid polyurethane foams?RPUF?that have a large industrial advantage in security,cost-effective and so on,were prepared with inorganic/organic flame retardants.But the complex research of the system is not pefect.The inorganic/organic flame retardant compound systems include Triethyl phosphate?TEP?/ ammonium polyphosphate?APP?,Methyl phosphonate?DMMP?/melamine?MEL?and Ammonium polyphosphate?APP?/expandable graphite?EG?.The effects of each flame retardant system on the structure,apparent density,mechanical and flame retardancy of RPUFs were studied.In the TEP/APP and DMMP/MEL flame retardant systems,with the increase of inorganic flame retardant content,RPUFs' cell became smaller when the foam density and the compressive strength increased.The limit oxygen index?LOI?is related to the compounding proportion.The optimal mass ratio of TEP/APP and DMMP/ MEL was 1:4 and 1:3,and LOI could reach 22.7% when the content was 15wt%.DMMP/MEL had better smoke suppression performance than TEP/APP,and DMMP/MEL smoke density was 24.0%.The optimum mass ratio of APP/EG flame retardant system was 1:3.When the addition amount of the composite flame retardant was 20%,the comprehensive performance was the best.The compressive strength was 0.25 MPa,the impact strength was 0.061 k J·m^-2,and the LOI was 29.1%.The results showed that there was obvious synergistic effect in the flame retardants,and they were condensed phase flame retardant..