Combustion Inhibition Ability of Piperazine Phosphoramide Derivatives and Titanium Carbide on Epoxy Resin

Herein, piperazine phosphoramide derivatives (PPDO) and titanium carbide modified by hexadecyl trimethyl ammonium bromide (c-Ti3C2) were blended with epoxy resin (EP) to fabricate EP/c-Ti3C2/PPDO nanocomposites. According to thermogravimetric analyzer (TGA) results and pyrolysis kinetic analysis, EP/c-Ti3C2/PPDO nanocomposites can improve the thermal stability and the activation energy of EP. Furthermore, thermal degradation mechanism of EP and its nanocomposites with conversion between 0.55 and 0.99 conforms to the F3 model. With 1 wt% c-Ti3C2 and 3 wt% PPDO incorporated, the LOI value of EP/c-Ti3C2-1/PPDO-3 can reach up to 32% while achieves V-0 rating in the UL-94 test. Based on the cone calorimeter results, the peak heat release rate of EP/c-Ti3C2-1/PPDO-3 reduced by 40.1%. More continuous and dense phosphorus-rich char residues were produced for EP/c-Ti3C2-1/PPDO-3 nanocomposites, which can act as a physical barrier to hinder the heat transfer, protect the underlying polymers from further decomposition and isolate the diffusion of combustible gases. The synergistic effect between c-Ti3C2 and PPDO in catalytic carbonization obviously accounts for the improved flame retardant performance. This work provides an insight into the flame retardant mechanism and the thermal degradation mechanism of c-Ti3C2 and PPDO on EP, showing a promising application potential of c-Ti3C2 and PPDO in enhancing the thermal stability and flame retardancy of EP.