Nitrile (Buna-N, NBR, Acrylonitrile Butadiene Rubber)
Nitrile, also commonly referred to as Buna-N or NBR, 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. Hydrogenated versions of NBR (HNBR) have enhanced mechanical properties as well as greater thermal and chemical stability. Specific physical properties and chemical resistances vary by compound formulation.
NBR can be compounded for enhanced oil and fuel resistance, increased temperature flexibility, high hardness and extrusion resistance, low compression set, and a variety of other attributes. The physical properties of the compound largely depend on the Acrylonitrile content of the formulation. For example, high Acrylonitrile content causes increased oil and fuel resistance while adversely affecting low temperature flexibility and compression set resistance. It is important to consider the offsetting attributes when selecting an NBR formulation. Please contact a Marco Rubber engineer for assistance finding the best compound for your application.
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).
*Approximation for dry air service. Actual temperature range of a compound in an end-use application is highly dependent on part type, hardware configuration, applied forces, chemical media, pressure and thermal cycling effects, and other factors. Consult a Marco Engineer for more details.
Typical Applications and Products:
The range of performance characteristics of Nitrile allows it to be utilized in a diverse set of applications. NBR is often used for gaskets and o-rings in pneumatic, hydraulic, and fuel systems. V-packings and backup rings made from high-hardness Nitrile compounds are common in high pressure environments in the Oil and Gas industry. The abrasion and wear resistance of NBR make it useful for dynamic oil seals for rotary and reciprocating shafts. NBR is relatively easy to process which keeps costs down for custom extrusions and complex molds. Hardness ranges from 40 Shore A to 90 Shore A.
- Petroleum greases, mineral oils, vegetable oils
- Aliphatic hydrocarbons
- Hydraulic fluids (HFA, HFB, HFC types)
- Limited resistance to dilute acids, alkalis, and solvents
Not compatible with:
- Highly Aromatic fuels and hydrocarbons
- Weathering, sunlight and ozone
- Chlorinated hydrocarbons
- Polar solvents
- Glycol brake fluids
Compound and Product Options:
Not a complete list of offerings. Please contact a Marco Sales Consultant or Engineer to discuss additional options. See Popular Compounds list below for compound examples.
Hundreds more specialty compounds available. Contact a Marco Sales Consultant or Engineer for more information.
|Marco Compound Number||Hardness
|B1000 View Datasheet||70||Black||-31 (-35)||250 (121)||Lowest cost highest inventory general purpose commodity NBR compound. Compare to Parker N1470-70 and N0674-70 and Parco 4200-70 and 4900-70. Available in nearly any color and hardness.|
|B1001 View Datasheet||90||Black||-31 (-35)||250 (121)||General purpose, higher pressure applications. Compare to Parker N0552-90 and N1490-90 and Parco 4200-90 and 4900-90.|
|B1002 View Datasheet||70||Black||-31 (-35)||250 (121)||FDA compliant per 21 CFR 177.2600. Compare to Parker N0508-75 and N1069-70.|
|B1005 View Datasheet||90||Black||-31 (-35)||250 (121)||FDA compliant, higher hardness.|
|B1006 View Datasheet||50||Black||-31 (-35)||250 (121)||General purpose, lower hardness for lower closure force applications. FDA compliant and alternative colors available. Compare to Parker N0299-50.|
|B1010 View Datasheet||80||Black||-31 (-35)||225 (107)||General purpose, higher hardness. Compare to Parker N0368-80.|
|B1011 View Datasheet||70||Black||-31 (-35)||230 (110)||Internally lubricated with PTFE to reduce friction. Silicone oil and Moly (MOS2) internal lubricants available. Alternative hardness and colors also available.|
|B1017 View Datasheet||70||Black||-35 (-37)||250 (121)||UL 157 listed for several approved uses.|
|B1058 View Datasheet||70||Black||-31 (-35)||250 (121)||NSF 61 certified for drinking water applications.|
|B1063 View Datasheet||95||Black||-31 (-35)||250 (121)||Very high hardness for extreme pressure applications.|
|B1083 View Datasheet||70||Black||-65 (-54)||275 (135)||Improved lower and higher temperature resistance and improved oil resistance at higher temperature. Compare to Parker N0794-75 and M83461 and Parco 4367-70.|
|B1105 View Datasheet||70||Black||-31 (-35)||250 (121)||Metal detectable for contamination detection sensors. FDA compliant per 21 CFR 177.2600. Formulated for food contact and life science applications. Additional colors available.|
|B1122 View Datasheet||70||Black||-31 (-35)||250 (121)||NSF 51 certified for food contact.|
|M1000 View Datasheet||70||Black||-65 (-54)||275 (135)||Mil Spec (Military specification) AMS-P-25732, MS28775-### per MIL-P-25732C-(1).|
|M1001 View Datasheet||75||Black||-65 (-54)||275 (135)||Mil Spec (Military specification) AMS-P-83461, M83461/1-### per MIL-P-83461B#3. Improved low temperature resistance and hydraulic fluid resistance.|
|M1002 View Datasheet||65||Black||-65 (-54)||250 (121)||Mil Spec (Military specification) MS29513-###, MS29512-##, AMS-P-5315B.|
|M1004 View Datasheet||90||Black||-65 (-54)||275 (135)||Mil Spec (Military specification) MS28778, AMS-P-5510C.|
|M1005 View Datasheet||65||Black||-70 (-57)||200 (94)||Mil Spec (Military specification) AMS7271, AS3578.|