Silicone rubber umbrella skirt for extra-high voltage composite insulator and preparation method thereof

Abstract

The invention discloses a silicone rubber umbrella skirt for an extra-high voltage composite insulator and a preparation method thereof, and relates to the technical field of silicone rubber materials. According to the silicone rubber umbrella skirt for the extra-high voltage composite insulator, the silicone rubber umbrella skirt is prepared from the following raw materials in parts by weight: 100 parts of methyl vinyl phenyl silicone rubber raw rubber, 40-80 parts of an Mg-SiC compound, 50-70 parts of modified diatomite, 1.5-4 parts of a silane coupling agent, 3-5 parts of hydroxyl silicone oil, 4-7 parts of cyclic trisilazane, 5-8 parts of nano ZnO, 2-5 parts of titanium dioxide, 1.5-3 parts of a dispersing agent and 1-3 parts of a vulcanizing agent. The invention also discloses the preparation method of the silicone rubber umbrella skirt for the extra-high voltage composite insulator. The silicone rubber umbrella skirt has excellent electrical insulativity, flame retardance, hydrophobicity, high and low temperature resistance and mechanical strength, the pollution flashover resistance and aging resistance of the silicone rubber umbrella skirt are improved, the silicone rubber umbrella skirt is not easy to damage, and the service life of the composite insulator is prolonged.

Description

technical field [0001] The invention belongs to the technical field of silicone rubber materials, and in particular relates to a silicone rubber shed for UHV composite insulators and a preparation method thereof. Background technique [0002] Composite insulators, also known as polymer insulators, are mainly composed of three parts: silicone rubber shed sheath, fiberglass core rod and end fittings. Compared with traditional ceramic insulators and glass insulators, they have extremely strong hydrophobicity and hydrophobicity. , light weight, easy to transport and install, high strength and good mechanical properties, and extremely convenient in the process of operation and maintenance, therefore, it has been widely used in the field of electric power in our country. The umbrella cover and mandrel material of the composite insulator are made of organic materials, whose intermolecular bonding is weaker than inorganic materials such as porcelain and glass, and will occur under t...

AI Technical Summary

Problems solved by technology

Because the silicone rubber umbrella skirt is under the action of ultraviolet radiation for many years, the silicon-carbon bond and carbon-hydrogen bond will be broken to form free radicals, and the small molecular oligomers generated by the combination of the generated free radicals will volatilize, and the macromolecular polymers will crosslink each other. The cross-linking density of silicone rubber increases, the material hardens, and the tensile strength decreases; the silicone rubber shed has been exposed to high humidity or rain for many years, forming an acidic aqueous solution environment on the surface of the insulator, and hydrogen ions attack the silicon in the main chain of silicone rubber. The oxygen bond makes it break the bond, and the group after the bond break cannot be recombined, because the small molecule at the end of the hydroxyl group is generated under acidic conditions, and the inorganic filler aluminum hydroxide in the silicone rubber can react with the acidic substance to promote the silicone rubber. At the same time, the silicone rubber molecule contains terminal hydroxyl groups. Under high voltage and high current, the terminal hydroxyl groups trigger the release of the main chain of the silicone rubber molecular chain. The loss of water property will cause electric corrosion and tracking on the surface of the insulator, resulting in poor aging resistance and short service life of the silicone rubber shed

[0004] Chinese invention patent CN201510125814.2 discloses a high-voltage electric corrosion-resistant silicone rubber composition for composite insulators and its preparation method, which improves the electrical resistance of the silicone rubber composition for composite insulators by adding heat-conducting metal oxide nanoparticles Corrosion level, and retains good mechanical properties, but its hydrophobic performance is poor, pollution flashover resistance performance is average, resulting in the insulator's general anti-aging performance and short service life

Chinese invention patent CN201510066190.1 discloses a fluorosilicone rubber for aging-resistant porcelain composite insulators and its application. It is made of fluororubber raw rubber, silicone rubber compound rubber, aluminum hydroxide powder, fumed Pentasulfur agent, polytetrafluoroethylene powder and other raw materials are prepared, which have excellent tear strength and aging resistance. However, the composite insulator contains fluorine, which has a great impact on the environment. Corrosion performance, breakdown resistance and other general electrical properties, the raw material contains aluminum hydroxide, so that after a period of use, the composite insulator's water repellency and pollution flashover resistance performance will deteriorate, which can no longer meet the needs of the growing power industry. need

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