Acrylonitrile Butadiene Rubber (NBR)
NitrileNitrile is the most commonly used elastomer in the seal industry. Nitrile is a copolymer of two monomers;
Acrylonitrile (ACN) and Butadiene. The properties of this elastomer are ruled by its ACN content which is broken down into three classifications:
High Nitrile >45% ACN content
Medium Nitrile 30-45% ACN content
Low Nitrile <30% ACN content
The higher the ACN content, the better its resistance to hydrocarbon oils. The lower the ACN content the better its flexibility in low temperature applications. Medium Nitrile is, therefore, most widely specified due to its good overall balance in most applications. Typically, Nitriles can be compounded to work over a temperature range of -35°C to +120°C and are superior to most elastomers in regard to compression-set, tear and abrasion resistance. Nitrile posses excellent resistance to oil-based fluids, animal fats, vegetable oils, greases, water and air.