Phosphorus-containing hyperbranched polysiloxanes intercalated graphene oxide and their flame retardant effect on epoxy resin

Intrinsic flammability significantly impedes practical applications of epoxy (EP), despite many merits. Intercalation-functionalized graphene oxide (GO) has shown excellent performance in flame retardancy studies of polymers, but research investigating the effect of layer spacing on the flame-retardant performance of polymers is still lacking so far. Therefore, three GO flame retardants with different layer spacing were prepared to flame retardant EP. When the layer spacing of GO is 1.09 nm, the heat and smoke release from EP composites is effectively suppressed. This is attributed to the barrier effect and maze effect of GO as well as the synergistic effect between the intercalator and GO. Analysis shows that the layer spacing of GO affects the flame retardancy of the composite by influencing the formation of protective char layer.