Effect of aluminum diethylphosphinate on the thermal stability and flame retardancy of flexible polyurethane foams.

Flame retardant flexible polyurethane foam (FPUF) was prepared through a free-foaming method with aluminum diethylphosphinate (ADP) as additive. The influence of ADP on the morphology, thermal and flame retardant properties of the FPUF was investigated, and the flame retardant mechanism was further explored. TGA results indicated that the addition of ADP slightly affected the initial degradation temperature and the maximum degradation temperature. With the increase of the ADP loading, the char yield of the resultant FPUF gradually increased. When the ADP loading was 20%, the peak heat release rate and the total heat release of the resultant FPUF was reduced by 35% and 33%, respectively, compared to the unmodified FPUF. The addition of ADP improved the char formation of the FPUF, which could inhibit the transfer of oxygen and flammable gases between the flame and the underlying polymer and thus improve the fire retardancy. • Influence of ADP loading on the flame retardant property of FPUFs was studied. • The presence of ADP almost did not affect the thermal stability of FPUF. • Addition of ADP decreased the peak heat release rate and total heat release of FPUF. • ADP functioned as flame retardant in both gas phase and condensed phase. [ABSTRACT FROM AUTHOR]