| Silicone rubbers have in general the following advantageous: a wide service temperature range (-100~250℃); low toxicity; optical transparency; low chemical reactivity; excellent resistance to attack of oxygen and sunlight; and good insulated properties. Room temperature vulcanized silicone rubber adhesive (RTV-1 SRA), which has these advantages, has been widely used in various field. With the development of aviation and space technology, routes of improving bound and high-temperature performances of RTV-1 SRA have become a research focus.In this paper, RTV-1 SRA was prepared withα,ω-hydroxy terminated silicone as matrix and effects of contents of reinforcing agents(silica, calcium carbonate, montmorillonite), cross linking agents and catalyst on performances of RTV-1 SRA were studied.Testing results indicated that reinforcing effects of silica was better and contents of cross linking agents and catalyst should be controlled within certain extent so as to achieve better mechanical performance. The results showed viscosifier Viscosifier A and Viscosifier B had better performance; when Viscosifier A were added into RTV-1 SRA, the adhesive strength of RTV-1 SRA to aluminum reached 4.0MPa; When Viscosifier B was applied to RTV-1 SRA, the adhesive strength to nickel reached more than 0.8 MPa.The routes of improving bound and high temperature performances of RTV-1 SRA was introduced in the paper. The routes included adding the mixture of Cross Linking Agent B and Cross Linking Agent C, Si-N compounds, nanoparticles (TiO2, SnO2, ZnO,α-Fe2O3, CNT) into RTV-1 SRA. The results showed that RTV-1 SRA degradation initiated by terminal groups of silicone rubber was effectively eliminated and its thermal stability and bound performances were increased obviously.when TiO2,α-Fe2O3 or CNT were added into RTV-1 SRA, after aging at 350℃, the adhesive strength of RTV-1 SRA to aluminum reached 1.67MPa.
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