Three kinds of commonly used electromagnetic valve sealing material
NBR (nitrile butadiene rubber nitrilebutadienerubber） By and by the emulsion polymerization of acrylonitrile, butadiene nitrile rubber is mainly produced by emulsion polymerization at low temperature, excellent oil resistance, high wear resistance, good heat resistance, strong adhesive relay. The disadvantages of poor low temperature resistance, ozone resistance is poor, poor performance, flexible slightly lower. In addition, it also has good water resistance, air tightness and excellent bonding performance. Is widely used in various oil resistant rubber products, a variety of oil resistant gaskets, gasket, casing, flexible packaging, soft hose, printing and dyeing, plastic roller, plastic cable materials, etc. , in automotive industry, aviation, petroleum, photocopying etc become indispensable in the elastic material. Nitrile rubber with good oil resistance, oil resistance after thiokol and fluorine rubber, and the abrasion resistance and air tightness. Drawback is not resistant to ozone and aromatic nitrile butadiene rubber, halogenated hydrocarbon, ketone and ester solvent, for insulation. Main use nitrile rubber is used mainly for oil products, such as tubing, adhesive tape, rubber diaphragm and large oil capsule, etc. , are often used to make all kinds of oil resistant moulded products, such as o-ring, oil seal, cup, diaphragm valve, corrugated pipe, etc. , are used to make plastic board and wear-resistant parts. EPDM EPDM ( 乙烯- 丙烯- DieneMonomer) Epdm is ethylene, propylene and the conjugate dienes terpolymer, commercial production began in 1963. The world consumption is 800000 tons per year. EPDM's main feature is its superior resistance to oxidation and ozone resistance and erosion resistance ability. Because of the epdm belongs to the family of polyolefin, it has excellent curing characteristics. Of all the rubber, EPDM has the lowest proportion. It can absorb a large number of filler and oil and impact properties. So can make cheap rubber compounds. Molecular structure and characteristics of epdm is ethylene, propylene and the terpolymer of conjugated dienes. Dienes with special structure, only two, one of the keys to copolymerization, unsaturated double bond mainly as a cross-linking. Another will not become owner chain polymerization unsaturated, will only become a side chain. The main polymer chain epdm is completely saturated. This feature makes the epdm can resist heat and light, oxygen, especially ozone. Epdm is essentially non-polarity, polarity solution and chemical resistant, bibulous rate is low, it has good insulating properties. Features: 1, low density and high filling; 2, aging resistance; 3, corrosion resistance; 4, water resistance; 5, a hot water resistance; 6, electric performance; 7 and elastic; 8 and adhesion. VITON fluoroelastomer ( FKM) Molecules containing fluorine rubber, depending on the fluorine content of the monomer structure with various types; Currently widely used hexafluoride series of fluorine rubber was first by dupont to & other; VITON” Trade name listed. High temperature resistance is better than that of silicone rubber & hellip; … Chemical resistance, resistance to most of the oil and solvent ( Except ketone, esters) Ozone resistance, weatherability, are beautiful, but bad cold tolerance; General is widely used in vehicle, b goods, such as chemical plant of seal, using temperature range - 20 ℃ ~ 260 ℃, low temperature requires the use of low temperature resistant type can choose to apply to - 40 ℃, as the price is higher.