氧化铈协效膨胀型阻燃聚丙烯体系研究

Study of Synergistic Effects of Cerium Oxide on Intumescent Flame Retardant Polypropylene System

以磷酸、季戊四醇、三聚氰胺为原料合成了膨胀型阻燃剂季戊四醇磷酸酯三聚氰胺盐(PPM).采用摆锤冲击试验机、微机控制万能试样机等研究了氧化铈(CeO2)协效阻燃PPM/聚丙烯(PP)体系的力学性能,以极限氧指数(LOI)、热分析(TGA)和扫描电镜(SEM)考察了CeO2对PPM/PP体系的阻燃协效作用,探讨了作用机理.结果表明:适量CeO2的加入能够提高体系的LOI,PPM的质量分数为20%,CeO2的添加量为PPM/PP质量的1%时,LOI可达到最大值为30%;TG结果表明,CeO2的加入可以提高膨胀炭层在高温时的热稳定性,增加高温时残余物的量;膨胀炭层的SEM图表明,适量CeO2能够改善膨胀炭层的形貌,提高炭层的隔热隔质性能;适量的CeO2的加入可提高体系的缺口冲击强度,拉伸性能则略有下降.

Melamine salt of pentaerythritol phosphate （PPM） was synthesized with phosphoric acid,pentaerythritol and melamine. This flame retardant polypropylene containing cerium oxide （CeO2） can be used as a synergistic agent for the flame retardancy of intumescent flame retardant polypropylene system. The pendulum impact tester and universal material machine were used to evaluate the mechanical properties of intmescent flame retardant system;the limiting oxygen in- dex （LOI）, thermogravimetric analysis （TGA）, and scanning electron microscopy （SEM） were used to evaluate the synergis- tic effects of CeO2. The LOI value of the system increased when reasonable amount of CeO2 was added, and it,reached maxi- mum （30%）when the mass fraction of PPM was 20% and CeO2 added was 1% of the PPM/PP system. The TGA data shows that CeO2 can enhance the thermal stability of the intumescent flame retardant polypropylene system at high temperature and effectively increase the char residue formation. The morphological structures observed with SEM demonstrate that reason- able amount of CeO2 can improve the morphologies of intumescent char layer and the properties of heat insulation and barrier material. The reasonable amount of CeO2 in the system can increase its impact strength and decrease its tensile properties.