Hydrogenated nitrile rubber (HNBR)

AL-Gummi Hydrierter Nitrilkautschuk (HNBR)

Registered trade name: Therban

HNBR (Hydrogenated Nitrile Butadiene Rubber) is produced from NBR by catalytic hydrogenation and peroxide cross-linked. Complete hydrogenation of NBR produces a saturated rubber with characteristic properties such as resistance to heat, oil and ozone, combined with good mechanical properties.
As a result, the material gains temperature resistance. This elastomer is often used where NBR would be optimal, but temperatures are too high.
The main areas of application are heat-resistant seals and hoses, as well as toothed and V-belts. The catalytic hydrogenation of NBR is a very complicated process, so HNBR costs many times more than NBR.

Property spectrum of HNBR

Hardness 50 to 90 Shore A
Elongation at break 100 to 600
Maximum temperature +155° C (+175° C)
Minimum temperature -35°C
Electrical properties
Gas permeability very low, but lower than IIR
Resistance to ageing and ozone very good
Chemical resistance good against mineral oils, hydraulic fluids of low flammability, hot water, steam, aqueous acids and alkalis

Applications of HNBR

HNBR is used in many areas where good heat and oil resistance as well as good wear resistance are required. For example, in seals and hoses in the automotive sector and in mechanical engineering and for special seals in oil production.
In sealing technology, HNBR, which is significantly more expensive than NBR and is also a proven standard material for timing belts in car engines, is used primarily where higher temperatures and/or mechanical strength are required. Its strength is particularly in demand for applications such as O-rings, radial shaft seals, bellows and diaphragms. Particularly in the process industry, HNBR offers wide-ranging application possibilities. For example, HNBR is excellently suited as a flap seal material in the process industry. In dairies, the beverage industry and applications in contact with very greasy media, HNBR is the best solution.