纳米Al_2O_3对含磷环氧树脂体系的性能影响

THE INFLUENCE OF NANO-Al_2O_3 ON THE PROPERTIES OF PHOSPHORUS-CONTAINING FLAME RETARDED EPOXY RESINS

研究了以纳米Al_2O_3作为协同阻燃剂,对EP/DOPO和EP/HPCTP树脂固化物阻燃性能的影响。通过热重分析测试(TGA)、动态热机械分析测试(DMA)、氧指数测定(LOI)及垂直燃烧测试(UL-94)重点探讨了树脂固化物的耐热及阻燃性能。测试结果表明,含磷阻燃剂有助于提高环氧树脂固化物的阻燃性能,但会降低其玻璃化转变温度(Tg)。随着纳米Al_2O_3的加入,残炭率(800℃)、极限氧指数(LOI)得到进一步的提高,并且能够在一定程度上提升树脂固化物的玻璃化转变温度(Tg)和初始热裂解温度(T5%)。

In this work,nano-Al2O3 was used as the synergistic flame retardant to study its influence on the flame retardancy of the EP/DOPO and EP/HPCTP thermosets. The thermal stability and flame retardancy of the neat EP and flame retarded EP thermosets were studied by thermogravimetric analysis（ TGA）,dynamic thermomechanical analysis（ DMA）,limiting oxygen index（ LOI） and UL-94 vertical burning test. The results indicated that the phosphorus-containing flame retardant（ DOPO or HPCTP） contributed to improving the flame retardancy of the cured EP resins. However,it will result in the decrease of the Tgof the cured EP resins. Nevertheless,Nano-Al2O3 not only increased the char yield at 800 ℃ and LOI of the cured EP resins,but also improved the Tgand onset decomposition temperature of the cured EP resins to some extent. When the content of nano-Al2O3 was 4% in the cured EP resins,the LOI of EP-DOPO-Al2O3-4phr and EP-HPCTP-Al2O3-4phr achieved 36.4% and 41. 0%,and UL-94 V-0 rating was obtained,which indicated that nano-Al2O3 was an effective synergistic flame retardant to improve the flame retardancy of the EP/DOPO and EP/HPCTP thermosets.