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Silicone rubber has the following advantages : a very wide temperature range (-100 ~ 250 ℃), low toxicity , high transparency, chemical inertness, excellent weather resistance , good electrical insulation and the like . One-component room temperature vulcanizing (RTV-1) silicone rubber adhesive (SRA) as easy to use, without high-temperature curing , which is widely used in high-temperature components of the bonding , as the aviation , space technology, to further improve the RTV- 1 SRA heat resistance become a research hotspot. This selection terminal hydroxy polydimethylsiloxane ( 107 gum ) as a base rubber , a detailed study of nano reinforced filler, silane coupling agents , catalysts , thickeners , pigments, the RTV-1 silicone rubber adhesive of the adhesive of bonding properties , and prepared at room temperature with excellent adhesion of RTV-1 silicone rubber adhesive . The results show that the nano-silica RTV-1 can greatly improve the mechanical properties of silicone rubber adhesives , tackifiers A and B can significantly improve the tackifier adhesive bonding properties to the metal substrate , added tackifier agent A , the adhesive shear strength of aluminum 4.0MPa, B adding a tackifier , the adhesive shear strength of nickel 0.8MPa. This detailed study of the RTV-1 silicone rubber to improve heat resistance of the adhesive means , including nano filler surface modification , adding a silazane , a mixed coupling agent , adding heat-resistant additive ( titanium dioxide , tin dioxide nano , zinc oxide , iron oxide red and carbon nanotubes , etc. ) and other methods. The results showed that the addition of modified nano-silica , and silazanes can be eliminated to improve hydroxy thermal stability of silicone rubber ; using an alcohol -based coupling agent B and C mix alcohol type coupling agent can improve the coupling of silicone rubber heat resistance ; resistant additive to be added to further improve the high temperature performance of silicone rubber , wherein the nano- titanium dioxide , iron oxide red , and carbon nanotubes added to increase the heat resistance of silicone rubber is more obvious, the use of the three heat-resistant additives prepared adhesives resistant to 350 ℃ , after 350 ℃ aging , shear strength still reached 1.67MPa.
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