THE ART AND SCIENCE OF ELASTOMERS
Built on real industrial experience, this masterclass bridges theory and production reality, offering insights that go beyond textbooks and into the core of rubber manufacturing.
Chapter 10
NBR Rubber
Some rubbers resist the weather.
Others resist time.
But when oil, grease and fuel are in the mix, only one rubber takes the lead: NBR.
Nitrile Butadiene Rubber is the workhorse of oil-handling applications, powering seals, hoses, gaskets and O-rings that face petroleum-based fluids every day.
First developed in Germany in the 1930s, NBR became critical during World War II, when industries urgently needed oil-resistant alternatives to natural rubber. Its legacy has continued ever since, sealing the machines that move the modern world.
NBR’s strength lies in its chemistry. Its polar molecular structure makes it compatible with fuels, oils and hydraulic fluids. Where non-polar rubbers like EPDM swell and fail, NBR holds its shape, maintaining sealing force even under long-term chemical exposure.
That’s why you’ll find it everywhere.
In vehicles, it seals fuel and protects engines. In industry, it keeps hydraulics, pumps and compressors running. And in energy and heavy equipment, it holds pressure inside O-rings and rotary seals where failure isn’t an option.
Wherever oil, pressure and motion meet, NBR is usually doing the job.
It’s adaptable, too. Formulated across a wide hardness range, NBR can be compounded for abrasion resistance, flame retardance, or even food-contact compliance. Most standard grades operate between –30 °C and +100 °C, with special formulations extending those limits further.
But NBR isn’t without weaknesses.
Outdoors, it ages poorly. Sunlight, ozone and UV attack its surface, causing cracks and loss of elasticity. Continuous heat above about 100 °C also shortens its service life. That’s why NBR is usually kept inside the machine, where the environment is harsh, but controlled.
It isn’t flashy, but it’s vital.
NBR is why hydraulics stay sealed, fuel lines don’t leak and engines hold pressure.
But when heat rises and stresses grow higher, NBR reaches its limits.
That’s when engineers turn to its tougher cousin: HNBR.
