Nitrilkautschuk (NBR)

AL-Gummi Nitrilkautschuk (NBR)

Acrylonitrile butadiene rubber (NBR), also called nitrile rubber
Registered trade name: Perbunan (formerly Buna N)

The copolymerisation of acrylonitrile and butadiene gives NBR exceptionally good resistance to mineral oil and fuel, as well as a low compression set. It is therefore the ideal sealing material for the media mentioned. NBR has its main areas of application where, in addition to good properties, high swelling resistance to mineral oils and fuels as well as resistance to ageing, heat and abrasion are required. The main applications are seals, hoses and diaphragms.

Property spectrum of NBR

Hardness 40 to 90 Shore A
Elongation at break 100 to 700% and higher
Maximum temperature +100° C
Minimum temperature -20°C
Electrical properties not suitable for electrical insulation, as NBR is to be regarded as a semiconductor
Gas permeability lower than NR, SBR, EPDM but higher than IIR
Ageing and ozone resistance Ageing better than NR and SBR, ozone resistance lower than NR
Chemical resistance Very good against grease and mineral oil

Applications of NBR

Nitrile rubber is used for oil and fuel-resistant seals, moulded parts, diaphragms and hoses in motor vehicles and mechanical engineering. Further applications are roller covers, gas and air conditioning hoses, according to its good oil and grease resistance. Pneumatic and hydraulic seals can be made from this rubber as well as O-rings and radial shaft seals.