含铂催化剂的硅胶泡沫阻燃性能实验研究

Experimental Study on Flame Retardancy of Silicone Foam Containing Platinum Catalyst

为研究不同含量铂催化剂对硅胶泡沫阻燃性能的影响,利用端乙烯基硅氧烷、α,ω-二羟基聚二甲基硅氧烷、含氢硅油等原料和不同含量的铂催化剂制成样品,对样品(铂催化剂量为0.2～0.8g)的极限氧指数LOI、垂直燃烧、热释放速率、热稳定性及烟密度进行测试。结果表明:铂催化剂添加量为0.8g时氧指数为29.1%,垂直燃烧达到UL-94V-0,阻燃性能相对较好;与铂催化剂添加量为0.2g的样品相比,其热释放速率下降了36.5%,表明减缓了热裂解速率,降低了火灾危险性;炭渣表面裂缝窄小,表明铂催化剂量的增加有利于材料炭化层的形成,烟密度等级(SDR)由9.53下降到2.27,下降了76.2%,最大烟密度(MSD)下降了75%;由TG曲线得铂催化剂添加量为0.8g时质量损失为28.09%,比铂催化剂添加量为0.2g时质量损失减少了14.45%,表明铂催化剂添加量为0.8g的试样稳定性更好。因此,增加铂催化剂的量可以改善硅胶泡沫材料的阻燃性能。

In order to study the influence of the platinum catalyst on the flame retardancy of the silicone foam,different samples were made by using raw materials such as terminal vinyl siloxane,α,ω-dihydroxy polydimethylsiloxane and hydrogen-containing silicone oil and adding different contents of platinum catalyst.The limiting oxygen index(LOI),vertical burning,heat release rate,thermal stability and smoke density of the prepared samples(containing 0.2—0.8g platinum catalyst)were tested.The results showed that the flame retardancy of 0.8g was relatively better,the oxygen index was 29.1% and the vertical burning reached UL-94V-0.Compared with addition of 0.2g platinum catalyst samples,the heat release rate decreased by 36.5%,indicating that the rate of thermal cracking was reduced and the risk of fire was reduced.The narrow surface cracks of cinder showed that the increase of platinum catalyst was favorable for the formation of carbonized layer of the material.The smoke density(SDR)fell from 9.53to2.27,down 76.2% and the most smoke density(MSD)decreased by four times.The mass loss of 0.8g from TG curve was28.09%,which was 14.45%lower than that of 0.2g mass loss,indicating that the stability of 0.8g sample was better.Therefore,increasing the amount of platinum catalyst could improve the flame-retardant properties of silicone foam.