Know Your Non-Metallics: Nitrile Rubber

One of the most common materials requested in the world of elastomers is nitrile rubber.  Nitrile is prized for being very economical and exhibits superior resistance to oil, fuel and other petroleum-based fluids.

Also known by names including NBR, Buna-N or acrylonitrile butadiene rubber, nitrile is a synthetic rubber, first patented in 1934. It’s gone on to become one of the more popular compounds used in all sorts of applications, but in particular low-temperature applications, the automotive industry and marine and aircraft fuel systems.

Its widespread use comes thanks in large part to nitrile’s highly resistant properties to petroleum-based oils, fuels, solvents, hydraulic fluids, propane, greases and water.

With a working temperature range of roughly -40 to 250 degrees Fahrenheit, nitrile can handle all but the most extreme of automotive settings. While nitrile’s temperature range isn’t as wide as silicone or some other synthetic rubber materials, its impressive fuel resistance continues to make it a popular and cost-effective choice.

Nitrile also adds a good balance of other desirable properties, including low compression set, high abrasion resistance and impressive tensile strength.

Nitrile compounds are chemically comprised of acrylonitrile and butadiene — with the ratio between the two adjusted in different variants dependent on the fuel/oil resistance required. The amount of acrylonitrile in the compound can range between 14-50%, with a higher percentage increasing the material’s resistance.

However, the rubber will have less flexibility, especially at lower temperatures, the higher the percentage of acrylonitrile in the material. Selecting a material variant with the proper ratio and balance between resistance and flexibility is critical to each manufacturer’s specific application.

Many automotive seals, gaskets, fuel hoses, transmission belts and more are made from variations of nitrile, striking the right balance between resistance and flexibility in each unique instance. Off-road equipment, marine and aerospace fuel systems, disposable gloves and FDA-approved food-service applications are some of the non-automotive uses where nitrile has become popular as well.

Have any questions, want to learn more about nitrile’s advantages and disadvantages versus other synthetic rubbers, or are you ready to request a quote for the nitrile seals and gaskets needed for your production? Reach out the Breiner Non-Metallics team today.