Combustion and Thermal Properties of Flame Retardant Polyurethane Foam With Ammonium Polyphosphate Synergized by Phosphomolybdic Acid

Phosphomolybdic acid (PMA) as a synergist was added into polyurethane (PU) rigid foam with ammonium polyphosphate (APP) to improve its flame retardancy and thermal stability. The combustion performance of PU studied by limiting oxygen index (LOI), UL-94, cone calorimeter. degradation behavior determined thermogravimetric analysis (TG) infrared spectroscopy (TG-IR). Experimental results showed that the introduction PMA could further retardant PU/APP composites significantly increase amount carbon residue at high temperatures. Adding 3wt% containing 12wt% APP make pass UL-94 V-0, 800°C 69.16% in air atmosphere, decrease THR 24.62% compared those PU/15APP. TG-IR presence reduced production small-molecule gas-phase products. As for mechanical properties composites, addition influences their density compressive strength obviously. suggest have good synergistic on can reduce fire risk.