309 2 – Hydrogenated Nitrile Butadiene Rubber (HNBR)

ASTM D2000 Classification: DH

Temperature Range:

-50°C to +150°C  (-20°F to +260°F)

Intermittent High 165°C (Int 285°F)

Properties

Acrylonitrile or Nitrile as it’s more commonly referred to, is a copolymer of Acrylonitrile and Butadiene. The Nitrile content varies in commercial products from 18% to 50%, the higher the Nitrile content the better the resistance to petroleum oils and hydrocarbon fuels, but low temperature flexibility decreases.

As Nitrile has an excellent resistance to petroleum products, and an ability to be compounded for service over a wide temperature range, Nitrile is the most widely used elastomer in the seal industry today. Nitrile compounds are superior to most elastomers with regard to compression set, tear, and abrasion resistance but have limited resistance to ozone, sunlight, or weather. To obtain good resistance to lower temperatures, it is often necessary to sacrifice some high temperature resistance. Nitrile should not be kept near electric motors or other ozone generating equipment and should not be kept in direct sunlight.

HNBR Specific Properties

Hydrogenated Nitrile Butadiene Rubber (HNBR), also known as Highly Saturated Nitrile (HSN), is a special class of nitrile rubber (NBR) that has been hydrogenated to increase saturation of the butadiene segment of the carbon polymer backbone. By hydrogenating the nitrile copolymer, HNBR fills the gap left between NBR, EPDM and FKM elastomers where high temperature conditions require high tensile strength while maintaining excellent resistance to motor oils, sour gas, amine/oil mixtures, oxidized fuels, and lubricating oils. HNBR is resistant to mineral oil-based hydraulic fluids, animal and vegetable fats, diesel fuel, ozone, sour gas, dilute acids and bases. HNBR also resists new bio-oils (biological oils). HNBR is suitable for high dynamic loads and has a good abrasion resistance.

Full data sheets for all grades are available on request.

* The information above is supplied in good faith and believed to be correct. This information is supplied upon the condition that persons receiving this will make their own determination as to its suitability for their purposes prior to use. EMI makes no representations or warranties, either expressed or implied with respect to the information or the product to which this information refers.