电力封堵用缩合型硅橡胶泡沫防火材料的制备及性能

研究了不同黏度和用量的乙烯基硅油、具有不同形态的防火填料对脱氢缩合型硅橡胶泡沫材料泡孔结构及防火性能的影响，使用橡胶加工分析仪表征了硅橡胶发泡过程中的发泡速率和交联速率，同时考察了氢氧化铝、云母、硅灰石3种填料对硅橡胶泡沫材料防火性能的影响。结果表明，不加入乙烯基硅油时，硅橡胶泡沫材料的储能模量较低，泡孔以闭孔结构为主；乙烯基硅油的加入提高了硅橡胶泡沫材料的交联速率和储能模量，使之形成较多的开孔结构，同时对硅橡胶泡沫材料泡孔尺寸分布也有影响；加入片状云母容易造成泡孔的坍塌或破裂，但是经火焰烧蚀后泡孔结构和烧蚀面的完整性保持较好，所形成的完整的陶瓷化阻隔层可起到较好的防火作用，而加入氢氧化铝和硅灰石后硅橡胶泡沫材料烧蚀后开裂比较严重。

Preparation and properties of condensed silicone rubber fireproof foam for power plugging

The effects of the viscosity and content of vinyl silicone oil and fireproof fillers with different shape on the cell structure and fire resistance of condensed silicone rubber foam materials were stu-died. The foaming rate and crosslinking rate of silicone rubber foam during the foaming process was characterized by the rubber processing analyzer. At the same time, the effects of the shape of aluminum hydroxide, mica and wollastonite on the fire resistance of silicone rubber foam were also investigated. The results showed when no vinyl silicone oil was added, storage modulus of silicone rubber foam whose cell structure of was mainly closed was lower. The addition of vinyl silicone oil increased the crosslinking rate and storage modulus of silicone rubber foam, and caused easily more open cell structures, and also had an impact on the cell size distribution of silicone rubber foam. The addition of lamellar mica was likely to result in the collapse and rupture of cell. However, the integrity of the cell structure and the ablation surface were well maintained after the flame ablation, and the complete ceramic barrier layer could play a good role in the fire prevention. In the other hand, silicone rubber foam materials with aluminum hydroxide and wollastonite were seriously cracked after the flame ablation.