镀镍石墨/甲基乙烯基硅橡胶导电复合材料的制备与性能

Preparation and properties of nickel coated graphite/methyl vinyl silicone rubber electric conductive composites

研究了硅烷偶联剂的种类、用量以及导电填料的用量对镀镍石墨/甲基乙烯基硅橡胶导电复合材料硫化特性、导电性能和力学性能的影响,探讨了复合材料中导电网络的形成机理。结果表明,采用含有双键的硅烷偶联剂处理镀镍石墨后,复合材料的硫化时间明显延长,硫化速率减慢;用6质量份乙烯基三乙氧基硅烷对镀镍石墨进行表面处理后,复合材料的导电性能和力学性能均得到提高;随着镀镍石墨用量的增加,复合材料的体积电阻率逐步下降,并且出现逾渗现象;采用偶联剂进行表面处理后的镀镍石墨有利于其在基体中分散形成相对稳定的刚性填料网络,使材料获得较低的体积电阻率。

The effect of the types and amount of silane coupling agent, amount of electric conductive filler on curing characteristics as well as electrical conductivity, mechanical properties of nickel coated graphite/methyl vinyl silicone rubber （MVQ） composites were studied. Meanwhile, the mechanism on the formation of conductive network was discussed. The results showed that the curing time increased obviously and the curing rate decreased after the nickel coated graphite treated with silane coupling agent containing double-bond was used. The conductive properties and mechanical properties of nickel coated graphite/MVQ composites were improved when the amount of vinyltriethoxysilane was 6 phr. The volume resistivity gradually declined and the percolation threshold was occured with the increase of filler loading. The relative stability and rigid of network were greatly improved, and 1he conductive filler in the rubber matrix was dispersed easily after nickel coated graphite was treated with silane cou- pling agent. The treatment has an advantage of stabilizing conductive network and dropping volume resistivity of the composites.