氧化铋在膨胀阻燃聚丙烯体系中的催化协效作用

Effect of Bi_2O_3 on Flame Retardancy and Properties of PP

将聚磷酸铵(APP)和双季戊四醇(DPER)膨胀型阻燃剂应用于聚丙烯(PP)的阻燃,并加入少量氧化铋(Bi2O3)。采用极限氧指数、烟密度和热分析等表征其阻燃性能。结果表明,加入少量的Bi2O3(0.1%质量分数,下同),可以提高体系的氧指数,降低体系的烟密度。热失重分析表明,Bi2O3加入可以使APP生成更多的固相残留物,催化膨胀阻燃剂交联成炭,高温时残炭增加,阻燃体系的最大热失重速率对应温度后移。同时热老化实验表明,Bi2O3的加入没有加快体系热老化的现象。

The effect of Bi2O3 on flame retardant synergism of ammonium polyphodphate （APP） /D-pentaerythrito （DPER） /polypropylene （PP） intumescent flame retardant system was studied. Influence of Bi2O3 on intumescent flame retardancy PP was analyzed by limiting oxygen index, smoke density and thermogravimetry analysis. The result shows that Bi2O3 promotes APP residual quantities and increases the thermal stability of the system. Moreover, the law of the effect of Bi2O3 was also researched. The limiting oxygen index （LOI） values at first increase with amount of Bi2O3 until a maximum in LOI is reached. With further increase in the Bi2O3 concentration the LOI begins to decrease. The highest LOI value obtained in this experiment is 25.2 with amount of 0.1% Bi2O3.