Nitrile, also commonly referred to as Buna-N or NBR, is a copolymer of Acrylonitrile and Butadiene.
NBR O rings Service Temperature Range*
–31°F (–35°C) to 230°F (110°C)
Specialty formulations, Low Temperature: –76°F (–60°C)
Specialty formulations, High Temperature: 275°F (135°C).
Buna-N is a copolymer of Acrylonitrile and Butadiene. Nitrile is the most commonly used elastomeric material for molded and extruded products. This material offers relative low cost, good mechanical properties, and resistance to many common oils, fuels and lubricants. NBR has poor resistance to weathering, sunlight and ozone so it is best used in enclosed environments where parts are not exposed to the elements.
Buna-N O-Rings Chemical Compatibility and Resistance:
Petroleum greases, mineral oils, vegetable oils
Hydraulic fluids (HFA, HFB, HFC types)
Limited resistance to dilute acids, alkalis, and solvents
Buna-N O-Rings Not Compatible With:
Highly Aromatic fuels and hydrocarbons
Weathering, sunlight and ozone
Glycol brake fluids