What is Hydrogenated Nitrile Rubber (HNBR)?

Hydrogenated nitrile rubber (HNBR) is a synthetic rubber that is produced by partially hydrogenating nitrile butadiene rubber (NBR). This process improves the heat and chemical resistance of the material, while maintaining the good mechanical properties of NBR.

HNBR is a copolymer of acrylonitrile and butadiene. The acrylonitrile content of HNBR typically ranges from 30 to 50%. The higher the acrylonitrile content, the better the oil and fuel resistance of the material, but the lower the low temperature flexibility.

HNBR can be cured with either sulfur or peroxide. Sulfur-cured HNBR compounds have better mechanical properties, while peroxide-cured HNBR compounds have better chemical resistance.

Properties of Hydrogenated Nitrile Rubber

HNBR has a number of excellent properties, including:

High temperature resistance: HNBR can withstand continuous temperatures of up to 150°C (302°F).

Oil and fuel resistance: HNBR is resistant to a wide range of oils and fuels, including aliphatic hydrocarbons, aromatic hydrocarbons, and synthetic fluids.

Good mechanical properties: HNBR has good tensile strength, tear strength, and abrasion resistance.

Ozone resistance: HNBR is resistant to ozone attack.

Good low temperature flexibility: HNBR has good low temperature flexibility, down to -40°C (-40°F).

Applications of Hydrogenated Nitrile Rubber

HNBR is used in a wide range of applications, including:

Automotive: HNBR is used in automotive applications such as engine seals, fuel system seals, and transmission seals.

Aerospace: HNBR is used in aerospace applications such as fuel system seals, landing gear seals, and aircraft engine seals.

Industrial: HNBR is used in industrial applications such as chemical processing equipment seals, oil and gas equipment seals, and food processing equipment seals.

Oil and gas: HNBR is used in oil and gas applications such as wellhead seals, downhole seals, and pipeline seals.

Advantages of Hydrogenated Nitrile Rubber

HNBR has a number of advantages over other elastomers, including:

Better temperature resistance than NBR

Better oil and fuel resistance than NBR

Good mechanical properties, similar to NBR

Ozone resistance

Good low temperature flexibility

Lower cost than fluoro elastomers (FKM)

Disadvantages of Hydrogenated Nitrile Rubber

HNBR has a few disadvantages, including:

Not as good oil and fuel resistance as FKM

Not as good low temperature flexibility as EPDM

Higher cost than NBR

Conclusion

Hydrogenated nitrile rubber (HNBR) is a versatile elastomer with excellent performance in a wide range of applications. It is known for its high temperature resistance, oil and fuel resistance, and good mechanical properties. HNBR is used in a variety of industries, including automotive, aerospace, industrial, and oil and gas.

Additional Information

HNBR is a relatively new elastomer, having been first introduced in the early 1980s. However, it has quickly become one of the most popular elastomers for demanding applications.

HNBR is available in a variety of forms, including sheets, rolls, molded parts, and extruded products. It can also be compounded with a variety of additives to improve its performance for specific applications.

HNBR is a recyclable material. It can be recycled using conventional rubber recycling processes.

Future of Hydrogenated Nitrile Rubber

HNBR is a growing market, as more and more industries are discovering its benefits. The development of new HNBR compounds with improved properties is also driving growth in the market.

HNBR is expected to continue to be a popular elastomer for demanding applications in the future.