Hydrogenated Nitrile Rubber (HNBR)
The properties of Hydrogenated Nitrile Rubber (HNBR) are dependent upon the acrylonitrile content and the degree of hydrogenation of the butadiene copolymer. They have a better oil and chemical resistance than Nitrile Rubber and can withstand much higher temperatures.
HNBR has excellent resistance to hydrogen sulphide, steam, hot water and ozone. Physical properties (e.g. tensile and tear strength, elongation, abrasion resistance, compression-set, etc.) are also excellent and compounds display strong dynamic behaviour at elevated temperatures.
HNBR can either be cured with sulphur or peroxide, depending upon which properties are the most important.
Typical applications include accumulator bladders, diaphragms, gaskets and seals. Limitations include poor electrical properties, poor flame resistance and attack by aromatic oils and polar organic solvents.