硅烷偶联剂对热硫化绝缘硅橡胶性能的影响探析

Analysis of the Effect of Silane Coupling Agent on the Properties of Insulating HTV Silicone Rubber

以甲基乙烯基硅橡胶为基料,气相法白炭黑为补强填料,氢氧化铝为阻燃填料,羟基硅油为结构化控制剂,添加硅烷偶联剂和硫化剂制得热硫化硅橡胶。研究了硅烷偶联剂种类和用量对硅橡胶力学性能、硫化特性、加工性能的影响。结果表明,加入硅烷偶联剂后能明显提升硅橡胶的拉伸强度和硬度,降低断裂伸长率、硫化速率和上辊操作性,产生明显的气味。含有乙烯基的硅烷偶联剂在加入后会提高胶料最高扭矩值;随着硅烷偶联剂用量的提升,硅橡胶拉伸强度先升后降,硫化速率逐步降低,上辊操作性下降,胶料气味不断增大;综合考虑各项性能,硅烷偶联剂推荐使用γ-(2,3环氧丙氧)丙基三甲氧基硅烷,其较佳用量为2份。

The HTV silicone rubber was prepared with methyl vinyl silicone rubber as the binder,fumed silica as the reinforcing filler,aluminium hydroxide as the flame-retardant filler,hydroxyl silicone oil as the structural controlled agent,and silane as the coupling agent and vulcanizing agent.The effects of the types and amounts of silane coupling agents on the mechanical properties,vulcanization characteristics,and processing properties of silicone rubber were studied.The results show that the silane coupling agent can significantly increase the tensile strength and hardness of the rubber compound,reduce the elongation at break,vulcanization rate,and roll operability,and produce certain odor.The vinyl silane coupling agents increased the MH value of the rubber.As the mount of silane coupling agent increased,the tensile strength first increased and then decreased,and the vulcanization rate decreased gradually as well as the operability of the roller and the rubber produced certain odor.Thus 2 phr of KH 560 silane coupling agent is recommended.