Combustion and thermal behaviors of the novel UV-cured intumescent flame retardant coatings containing phosphorus and nitrogen

Abstract

AbstractPhosphorus-containing tri(acryloyloxyethyl) phosphate (TAEP) was blended with triglycidyl isocyanurate acrylate (TGICA) in different ratios to obtain a series of UV curable intumescent flame retardant resins. The fire properties of the cured films were characterized by limited oxygen index (LOI), UL 94 and Cone Calorimeter. A distinct synergistic effect was found between TAEP and TGICA. The sample TAEP2 had the highest LOI (44) value among all resins. The cone calorimeter results showed that the sample TAEP2 had the lowest peak heat release rate (297 KW/M2). The thermal degradation was monitored by thermogravimetric analysis (TGA) and real-time Fourier transform infrared spectroscopy (RT-FTIR). The degradation mechanism is suggested in which the phosphate group in TAEP first degraded to form poly(phosphoric acid)s, which further catalyzed the degradation of the material to form char with emission of nitrogen volatiles from TGICA, leading to the formation of expanding char.