Lanthanum phenylphosphonate-based multilayered coating for reducing flammability and smoke production of flexible polyurethane foam

In the present work, lanthanum phenylphosphonate (LaPP)-based multilayered film was fabricated on the surface of flexible polyurethane (PU) foam by layer-by-layer self-assembled method. The successful deposition of the coating was confirmed by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). Subsequently, the thermal decomposition and burning behavior of untreated and treated PU foams were investigated by thermogravimetric analysis (TGA) and cone calorimeter, respectively. The TGA results indicated that T-max2 of treated PU foams were increased by approximately 15 degrees C to 20 degrees C as compared with untreated PU foam. The peak heat release rate (PHRR) and total heat release (THR) of PU-6 (with 19.5 wt% weight gain) were 188 kW/m(2) and 20.3 MJ/m(2), with reductions of 70% and 15% as compared with those of untreated PU foam, respectively. Meanwhile, the smoke production of treated PU foam was suppressed after the construction of LaPP-based coating.