HNBR O-Rings

HNBR (Hydrogenated nitrile) is the result of a process called hydrogenation, which involves adding hydrogen atoms to the butadiene segments of standard nitrile. This process significantly reduces the number of carbon-to-carbon double bonds, which are otherwise weak points in the polymer chain.

While the double bonds present in the butadiene segments of nitrile are essential for cross-linking, they are also highly susceptible to attack by heat, chemicals, and oxidation. In an ongoing effort to create more resilient materials, a new class of nitrile was developed in the 1980s. Initially referred to as highly saturated nitrile (HSN), it is now more commonly known as hydrogenated nitrile butadiene rubber (HNBR) or simply hydrogenated nitrile.