Rubber is a polymer material with unique mechanical properties, which is mainly characterized by large deformation under low stress and high elasticity that can restore its original shape after deformation. Good compatibility with various media; Its various properties can be adjusted by changing rubber varieties and formulations.
Nitrile butadiene rubber NBR
NBR is formed by copolymerization of acrylonitrile and butadiene, the acrylonitrile content is from 18% to 50%, the higher the acrylonitrile content, the better the resistance to hydrocarbon fuel oil of petrochemical oil, but the low temperature performance is worse, the general use temperature range is -25~120 ℃. Butadiene is one of the most commonly used rubbers for oil seals and O-rings.
Advantages:
• Good resistance to oil, water, solvent and high pressure oil.
• Good compression distortion, wear resistance and elongation.
Cons:
• Not suitable for use in polar solvents.
• For the production of fuel tanks, lubricating oil tanks and rubber parts used in fluid media such as petroleum hydraulic oil, gasoline, water, silicone grease, silicone oil, diester lubricating oil, ethylene glycol hydraulic oil, especially sealing parts. It can be said that the most widely used and lowest cost rubber seals at present.
Hydrogenated nitrile butadiene rubber HNBR
Hydrogenated butadiene rubber is a part of butadiene rubber removed by hydrogenation. After hydrogenation, its temperature resistance and weather resistance are much higher than that of ordinary butadiene rubber, and its oil resistance is similar to that of ordinary butadiene rubber. The general use temperature range is -25~150 ℃.
HNBR is widely used in air conditioning refrigeration industry, automotive engine system seals.
Carboxyl nitrile butadiene rubber XNBR
Carboxyl nitrile butadiene rubber is a polymer containing carboxyl monomer (acrylic acid or methacrylic acid) and butadiene, acrylonitrile by floating liquid terpolymer, carboxyl nitrile rubber has high oil resistance and good wear resistance, heat resistance. Compared with NBR and HNBR, the polar carboxyl group is introduced into XNBR molecular chain, which gives XNBR more excellent oil resistance, tear resistance, good wear resistance, heat resistance and aging resistance.
Mainly used in seals, oil well rubber products, rubber reciprocating oil seals, sealing rings, washers, O-rings, leather joints, rubber rollers, sole, heel, textile equipment and other rubber products.
Fluororubber FKM
Fluorine rubber molecules containing fluorine rubber, according to the fluorine content (that is, monomer structure) and there are various types. At present, the widely used hexafluoride fluorine rubber was first listed by DuPont Company. Excellent high temperature resistance, excellent chemical resistance, resistance to most oils and solvents (except ketones, esters), weather resistance and ozone resistance; The cold resistance is poor, and the general temperature range is -20~200 ℃. Huayi special formula can withstand low temperature to -40 ℃. Fluorine rubber can resist heat up to 250 ℃, and special formula can resist high temperature up to 300℃. It is resistant to most oils and solvents, especially all acids, aliphatic hydrocarbons, aromatic hydrocarbons and animal and vegetable oils.
Disadvantages: Not recommended for ketones, low molecular weight esters and nitro-containing mixtures.
Applications: • Automobile, locomotive, diesel engine and fuel system.
• Seals for chemical plants.
Perflurane rubber FFKM
Perfluoroether rubber, also known as perfluorinated rubber, has a wide range of chemical resistance properties, and its chemical resistance is close to PTFE. It can be attacked by more than 1,800 chemicals, solvents and plasmas. At the same time, it has excellent high temperature resistance. Swelling caused by chemical media can cause the volume of O-rings or other seals to expand beyond the space of the groove, and the seal will fail. Thermal decomposition of rubber at high temperature leads to seal failure. Huayi perfluoride seals can withstand more chemical media and higher temperature offset to meet the best sealing performance for special applications. Perfluorinated seals are mainly used in the semiconductor, valve, oil and gas industries.
Ethylene propylene rubber EPDM
Ethylene propylene rubber by ethylene and propylene copolymerization of the main chain is not double chain, so the heat resistance, aging resistance, ozone resistance, stability are very good, but can not sulfur. In order to solve this problem, a small amount of the third component of the double chain is introduced into the EP main chain, which can be sulfurized into EPDM, and the general use temperature range is -50~150 ℃. Excellent resistance to polar solvents. EPDM has good weather resistance and ozone resistance, excellent water resistance and chemical resistance, high temperature vapor resistance, good gas impermeability. Ketones may be used. However, it is not recommended for food use or for seals exposed to aromatic hydrogen, high-temperature water vapor environments, rubber zeros in braking (brake) systems, and seals in radiators (car water tanks).
Silicone rubber SIL
Silicone rubber is made of methylsiloxane copolymerization, so silicone rubber has excellent heat resistance, cold resistance, dielectric property, ozone resistance and atmospheric aging resistance, silicone rubber outstanding performance is the use of a wide temperature, can be used in -60 ° C (or lower temperature) to +280 ° C (or higher temperature) for a long time. However, the tensile strength and tear strength of silicone rubber and other mechanical properties are poor, at room temperature its physical and mechanical properties are not as good as most synthetic rubber, and in addition to nitrile silicon, fluorine silicone rubber, the general silicone rubber oil resistance, solvent resistance is poor, so silicone rubber is not suitable for ordinary conditions, but very suitable for many specific occasions. Special silicone rubber can achieve high tensile strength and high tear resistance requirements.
Fluorosilicone rubber FVMQ
Fluorosilicone rubber is a kind of silicone rubber with side chain introduction of fluoroalkyl. The introduction of fluorine atoms makes fluorine silicone rubber have good oil resistance and solvent resistance of fluorine rubber, and at the same time has the broad temperature resistance of silicone rubber. Fluorine silica gel has good heat resistance and excellent oil and solvent resistance, and has good stability at room temperature and high temperature.
Neoprene rubber CR
Neoprene rubber is made by polymerization of butene monomer. The vulcanized rubber has good elastic wear resistance, is not afraid of direct sunlight, has particularly good atmospheric aging resistance, is not afraid of fierce distortion, is not afraid of dichlorodifluormethane and ammonia and other refrigerants, is resistant to dilute acid, silicone ester lubricating oil, but is not resistant to phosphate ester hydraulic oil. It is easy to crystallize and harden at low temperature, poor storage stability, and large expansion in mineral oil with low aniline point. The general use temperature range is -50~150 ℃.
Advantages:
• Good elasticity and good compression deformation.
• The recipe is sulfur free and therefore very easy to make
• Resistant to animal and vegetable oils
• Flame resistant
• Will not be affected by neutral chemicals, esters, fats, various oils, solvents and physical properties.
Cons:
• Do not recommend the use of strong acids, nitrohydrocarbons, esters, chloroform and ketone chemicals.
• In certain refrigerants.
• Rubber parts or seals for household appliances.
• Suitable for making a variety of direct contact with the atmosphere, sunlight, ozone parts.
• Suitable for all kinds of rubber products with fire resistance and chemical corrosion resistance.
Acrylic rubber ACM
Alkyl Ester Acrylate is polymerized into elastomer as the main component, which has good resistance to petrochemical oil, high temperature and weather, but weak in mechanical strength, compression deformation rate and water resistance, which is slightly worse than general oil resistance adhesive. The general use temperature range is -25~170 ℃. It has good resistance to oxidation and good resistance to bending deformation. Suitable for automotive transmission system and power steering wheel.
Disadvantages: not suitable for hot water, brake oil.
Does not have low temperature resistance, is not suitable for phosphate, automotive transmission system and power system seals.
Polyurethane rubber PU
Polyurethane rubber is made by polymerization of polyester (or polyether) with a diisocyanate lipid compound. Its chemical structure is more complex than the general elastic polymer, in addition to the recurring carbamate groups, the molecular chain often contains ester, ether, aromatic groups and other groups. UR molecule main chain has high strength and high elasticity due to the hydrogen bond force.
• PU excellent wear resistance: Wear resistance is the highest in all rubber. Laboratory test results show that the wear resistance of UR is 3 to 5 times that of natural rubber, and it is often up to 10 times in practical applications.
• High strength and elasticity in Shore A60 to Shore A70 hardness range.
• Good oil resistance and drug resistance. UR has a small affinity with non-polar mineral oil, is almost resistant to erosion in fuel oil and mechanical oil, is much better than general purpose rubber, and is comparable to nitrile rubber.
• Low temperature resistance, ozone resistance, radiation resistance, electrical insulation.
The disadvantage of polyurethane rubber is that it has large swelling in alcohols, esters, ketones and aromatics.
Suitable for high-pressure seals and high-pressure water pipes, wear-resistant, oil-resistant rollers.