透明脱醇型室温硫化硅橡胶的研制

Preparation of transparent dealcoholized RTV silicone rubber

以多烷氧基硅烷为封端剂,对α,ω-二羟基聚二甲基硅氧烷(107硅橡胶)进行封端制得烷氧基封端的107硅橡胶,以此为基胶,加入交联剂、钛酸酯催化剂、气相白炭黑、自制稳定剂制备了一种透明脱醇型室温硫化硅橡胶。研究了不同类型的封端剂以及用量、不同黏度的107硅橡胶、不同型号的气相白炭黑、不同型号的钛酸酯对脱醇型室温硫化硅橡胶的性能和储存稳定性的影响。结果表明:以乙烯基三甲氧基硅烷为封端剂、107硅橡胶(20000 MPa·s∶80000 MPa·s=1∶1)为基础聚合物、Tyzor9000钛酸酯催化剂、卡博特LM-150气相白炭黑制备的透明脱醇型室温硫化硅橡胶外观透明、拉伸强度达1.75 MPa、断裂伸长率达415%,储存期大于12个月。

Siloxyl-terminated polydimethylsiloxane was prepared withα,ω-dihydroxy polydimethylsiloxane(107 silicone rubber)and polyalkoxysilane as the capping agent.Then it was used to prepare dealcoholized RTV silicone rubber adhensives by adding the cross-linking agent,titanate catalyst,fumed silica,self-compounded stabilizing agent into the alkoxy-terminated 107 silicone rubber.The influences of different types of the capping agents and their dosage,silicone rubber with different viscosity,different types of fumed silica and titanate catalyst on the properties and the storage stability of the silicone rubber were studied.The results show that the dealcoholized rtv silicone rubber has a better transparency,reaches a tensile strength of 1.75 MPa and an elongation at break of 415%and has a storage period of over 12 months with the vinyl trimethoxysilane as the end capping agent,107 rubber(20000 MPa·s∶80000 MPa·s=1∶1)as the basic polymer,Tyzor9000 as the titanate catalyst,and Cabot LM-150 as the fumed silica.