Physicochemical Property
Nitrile rubber is a copolymer of acrylonitrile (ACN) and butadiene. The performance of nitrile rubber mainly depends on the ACN component (generally 18%-50%). When the ACN content reaches 50%, the proportion of mineral oil and fuel oil resistance is high, but its elasticity and compression set become worse at low temperature; Nitrile rubber with higher erythrene content(i.e.78%) features excellent low temperature resistance,while the oil resistance under high temperature is weaker.In short, Nitrile rubber has excellent oil resistance and non-solvent resistance, and also has rather good mechanical energy and air tightness.Suitable for alphatic hydrocarbons (propane, ethane, mineral oil and grease, fuel oil), vegetable oil and animal oil, si licone oil, silicone Grease, chemical fire extinguishing agent, acid-base salt solution diluted at low temperature, and water below 100 °C, etc. medium. However, it has poor resistance to aromatic solvents, halogenated hydrocarbons, ketones and ester solvents, as well as strong acids and alkalis. The weather resistance and ozone resistance of nitrile rubber are not strong, but this problem can be solved well by using it with other materials. For example, nitrile rubber/polychrome can be made into oil-resistant magnetic rubber by adding a certain amount of magnetic powder. But its permanent compression set is poor.
Application
Nitrile rubber is widely used in various oil-resistant occasions, such as electronic injection injector parts in automobiles, various oil-resistant gaskets, seals, and rubber hoses. Seals, cushions and other oil-resistant and wear-resistant rubber 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.
Carboxyl nitrile rubber is similar to nitrile rubber, but the backbone of the polymer has been chemically modified with carboxylic acid groups, resulting in better abrasion and tear resistance than NBR. Therefore, XNBR is often used in environments with strict requirements on wear resistance and oil resistance. However, its low-temperature flexibility, water resistance and compression set are poor, and its mixing safety is not high.
