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 us engineer for assistance finding the best compound for your application.