聚磷酸铵和三氧化钼对聚氨酯软泡阻燃性能的影响

以聚磷酸铵（APP）和三氧化钼（MoO3）为阻燃剂，采用一步发泡法制备阻燃聚氨酯软质泡沫（FPUF），通过扫描电镜、氧指数仪、热重分析仪和锥形量热仪等测试手段研究了MoO3和APP对聚氨酯软泡的泡孔结构、热稳定性、阻燃性能以及产烟量的影响规律。研究表明：MoO3和APP均能提高聚氨酯软泡的阻燃性能，与纯聚氨酯软泡相比，当APP和MoO3的添加量均为7.5%时，阻燃聚氨酯软泡的总热释放量和总产烟量分别降低了44.2%、66.3%，表现出很好的阻燃和抑烟性能；探讨了APP和MoO3阻燃聚氨酯软泡的阻燃作用机理，APP在气相和凝聚相发挥阻燃作用，在气相中通过生成含磷官能团捕获气相中的自由基，在凝聚相中发挥催化成炭的作用，MoO3能促进热裂解聚氨酯催化成炭，提高成炭率，使炭层致密，并提高聚氨酯软泡的热稳定性，有效提高聚氨酯软泡的火灾安全性。

Effects of ammonium polyphosphate and MoO3 on flame retardancy of flexible polyurethane foam

Flame retardant flexible polyurethane foam (FPUF) were prepared by one-step foaming with ammonium polyphosphate (APP) and molybdenum trioxide (MoO3) as flame retardants. The effects of MoO3 and APP on the cellular structure,thermal stability, flame retardancy and smoke production of polyurethane foam were studied by means of scanning electron microscopy, limiting oxygen index, thermogravimetric analyzer and cone calorimeter. The results show that MoO3 and APP can improve the flame retardant performance of flexible polyurethane foam. Compared with pure flexible polyurethane foam, when the addition of APP and MoO3 is 7.5%, the total heat release and total smoke production of flame retardant flexible polyurethane foam are reduced by 44.2% and 66.3% respectively, showing better flame retardant and smoke suppression performance; The flame retardant mechanism of APP and MoO3 flame retardant flexible polyurethane foam is discussed. APP plays a flame retardant role in the gas phase and condensed phase. Free radicals in the gas phase are captured by generating phosphorus containing functional groups in the gas phase. The condensed phase plays a role in catalytic carbonization. MoO3 promotes the catalytic carbonization of pyrolysis polyurethane, improves the carbonization rate, compacts the carbon layer, and improves the thermal stability of flexible polyurethane foam. The fire safety of flexible polyurethane foam is effectively improved.