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Nitrile rubber, also known as Buna-N, Perbunan, acrylonitrile butadiene rubber, and NBR, is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene.Trade names include Nipol, Krynac and Europrene.Nitrile butadiene rubber (NBR) is a family of unsaturated copolymers of 2-propenenitrile and various butadiene monomers (1,2-butadiene and 1,3-butadiene).rade names include Nipol, Krynac and Europrene. Nitrile butadiene rubber (NBR) is a family of unsaturated copolymers of 2-propenenitrile and various butadiene monomers (1,2-butadiene and 1,3-butadiene).
Subsequent improvements to the material properties, over that of a nitrile rubber (NBR), include greater thermal stability, broader chemical resistance, and greater tensile strength. HNBR is classified by ASTM as a DH-type polymer.