含氢氧化铝RTV-2硅橡胶泡沫的阻燃抑烟性能研究

Study on flame retardancy and smoke suppression performance of RTV-2 silicone rubber foam containing aluminum hydroxide

为研究氢氧化铝对RTV-2硅橡胶泡沫材料阻燃性能的影响,利用端乙烯基二甲基硅氧烷、气相法白炭黑、α,ω-二羟基聚二甲基硅氧烷、含氢硅油和氢氧化铝等原料制成硅橡胶泡沫材料,对其氧指数、烟密度、热稳定性和力学性能进行测试。研究结果表明:氢氧化铝的量从5%增加到25%时,硅橡胶泡沫阻燃性能增强,氧指数增加到34.1%;发烟量减少,最大烟密度和烟密度等级最多降低50.9%和52%;热稳定性提升,质量损失最少为25.65%;力学性能降低。综合考虑材料的阻燃抑烟性能和力学性能,添加量为15%时最佳。对15%的试样进行CONE测试,与原样相比,其燃烧过程的热释放速率下降了51%,FPI值提升到0.5,FGI值降低到1.09,能够有效提高阻燃抑烟性能。

In order to study the influence of aluminum hydroxide on the flame retardancy of RTV-2 silicone rubber foam,the material of silicone rubber foam was prepared by using the vinyl terminated dimethyl siloxane,fumed silica,α,ω-dihydroxy polydimethylsiloxane,hydrogen-containing silicone oil,aluminum hydroxide and other raw materials,then the oxygen index,smoke density,thermal stability and mechanical properties of the material were tested. The results showed that when the content of aluminum hydroxide increased from 5% to 25%,the flame retardancy of the silicone rubber foam strengthened,and the oxygen index increased to 34. 1%. Meanwhile,the smoke generation decreased,and the maximum smoke density and smoke density level decreased by 50. 9% and 52% at most,respectively. The thermal stability increased,the mass loss was25. 65% at least,and the mechanical properties decreased. Comprehensively considering the flame retardancy,smoke suppression performance and mechanical properties of the material,the optimal addition amount was 15%. The CONE tests were carried out on the sample with the addition amount of 15%,and compared with the original sample,the heat release rate during the combustion process reduced by 51%,the FPI value increased to 0. 5,and the FGI value reduced to 1. 09,which showed that it can improve the flame retardancy and smoke suppression performance effectively.