Nitrile Rubber (NBR, Buna-N)
Nitrile rubber, also known as Nitrile butadiene rubber (NBR) and Buna-N, is a synthetic copolymer composed of acrylonitrile and butadiene. Nitrile is widely used due to its resistance to oils, fuels, and other chemicals.
Nitrile is found in:
- Automotive, marine, and aeronautical fuel and oil systems
- Disposable non-latex gloves
- Belts, hoses, O rings, gaskets
- Oil seals
- Footwear and floor mats
Standard Compound: -40°C (-40°F) to 100°C (212°F)
Special Compound: -55°C (-67°F) to 135°C (275°F)
Hardness: 40 to 90 Shore A
ASTM D1418 Designation: NBR
ASTM D2000 Designation: BF, BG, BK, CH
Standard Colors: Black
Standard NBR compounds have a 34% acrylonitrile (ACN) content. However, the ACN content can be varied from 18% to 50% to adjust the temperature and resistance properties of the material.
Nitriles can be sulfur or peroxide cured which affects the temperature and hardness and compression set properties of the material.
Nitrile rubber compounds perform especially well in petroleum based fuels and oils, aliphatic hydrocarbons, vegetable oils, silicone oils and greases, ethylene glycol, dilute acids, and water below 100°C (212°F).
Nitrile rubber compounds are susceptive to the ozone, ketones, ethers, esters, aromatic hydrocarbons, automotive brake fluid, strong acids, and aldehydes. Products made with Nitrile rubber, such as non-latex gloves, may spontaneously oxidize when coming into contact with strong oxidizers.