Study on Flame Retardancy and Curing Properties of 2-methy-2,5-dioxo-1,2-oxaphospholane in Epoxy Resin

A reagent 2-methy-2,5-dioxo-1,2-oxaphospholane(OP) was introduced into epoxy resin/DDM system as both a flame retardant and a curing agent,for it containing phosphorus atoms and anhydride groups.It was found that OP played a good flame retardant effect on the epoxy resin/DDM system.The limiting oxygen index of the epoxy resin/DDM/OP system reached 24.2 % and UL 94 grade reached V-0 level.When the mole ratio of epoxy and acid anhydride groups was 1∶1,the curing process could be completed in 6 h at 160 ℃.