Effect of chelated to the surface of PBFA on the charring flame retardant and smoke suppression properties of epoxy resin

Here, a phosphazene-based flame retardant (PBFA) containing active amine groups was synthesized by hexachlorocyclotriphosphazene and N- aminoethylpiperazine and nickel ion ([Ni.sup.2+]) was chelated to the surface of PBFA (named as PBFA-[Ni.sup.2+]). Incorporation into epoxy resin (EP) with a loading of 6 wt% (named as EP/PBFA-[Ni.sup.2+]-6.0), enabled the composite to pass the vertical burning test (UL-94) V 0 rating. Peak heat release rate and the total smoke release of EP/PBFA-[Ni.sup.2+]-6.0 were decreased by 41.02% and 22.74% as measured by cone calorimeter tests. The production rate of CO was inhibited when PBFA-[Ni.sup.2+] was incorporated into EP.