High Nitrile Rubber, 85-95 °IRHD. High acrylonitrile (ACN) content. Copolymer of acrylonitrile and butadiene. ASTM designation = NBR. ISO designation = NBR. Aerospace Material Specification DTD5509 Grade A. (Inactive for new design). Applications: Synthetic rubber resistant to engine lubricating oils, greases and fuels. |