(1) Molecular structure
(2) Physical and chemical properties
Nitrile rubber is a copolymer of acrylonitrile (CAN) and butadiene. The performance of nitrile rubber mainly depends on the CAN component (generally 18%-50%). If the CAN content is higher than 50%, it has a strong resistance to mineral oil and fuel, but its elasticity at low temperature, The compression set rate becomes worse; the formula with higher butadiene (such as 78%) has good low temperature resistance, but it also sacrifices oil resistance at high temperatures. In short, nitrile rubber has excellent oil resistance and non-polar solvent resistance, as well as excellent mechanical properties and air tightness. Suitable for aliphatic hydrocarbons (propane, hexane, mineral oil and grease, fuel oil), vegetable oil and animal oil, silicone oil, silicone grease, chemical fire extinguishing agent, acid-base salt solution diluted at low temperature, and water below 100°C in. However, it has poor resistance to aromatic solvents, halogenated hydrocarbons, ketones and ester solvents, and strong acids and bases. The weather resistance and ozone resistance of nitrile rubber is not strong, but it can be well solved by using it with other materials, such as: nitrile rubber/polyvinyl chloride blend material, which not only has excellent weather resistance And the ability to resist ozone, and the ability of flame retardant, calendering, coloring is also very good, adding a certain amount of magnetic powder can be made into oil-resistant magnetic rubber, but its permanent compression deformation is poor.
(3) General temperature range: -40～100℃
Low temperature resistance grade: -55～100℃ High temperature resistance grade: -30～125℃ (air) -30～150℃ oil)
(4) Hardness range
Shore A is 40 degrees to 93 degrees.
(5) Color
Black, brown, green, white, red, yellow, blue, orange, gray, colors can also be specified by customers.
(6) Application
Nitrile rubber is widely used in various oil-resistant occasions. Fuel injector parts for electronic injection in automobiles, various oil-resistant gaskets, seals, and hoses. Seals, cushions and other oil-resistant and wear-resistant rubber parts in the hydraulic and pneumatic industry. In the nuclear industry, highly saturated nitrile rubber can also be used for seals in nuclear power plants due to its radiation resistance.
※Carboxylated nitrile rubber (XNBR)
Carboxylic nitrile rubber is similar to nitrile rubber, but the backbone of the polymer is chemically modified with carboxylic acid groups, resulting in better wear and tear resistance than nitrile rubber. Therefore, XNBR is often used in environments with harsher requirements for wear resistance and oil resistance. However, its low temperature flexibility, water resistance and compression set are poor, and the mixing safety is not high.
Temperature range: -20℃～100℃ (up to 125℃ in a short time).
Hardness range: Shore A50 degrees to 90 degrees.
