Hydrogenated Nitrile Butadiene Rubber (HNBR), also known as Highly Saturated Nitrile (HSN), is special class of nitrile rubber (NBR) that has been hydrogenated to increase saturation of the butadiene segment of the carbon polymer backbone. 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. This classification indicates 150ºC service temperature as well as less than 30% swell in IRM 903 oil. HNBR can be formulated to meet application temperatures ranging between -50°C and 165ºC.

Seals Eastern is proud to have chosen Zeon Chemical Zetpol ® brand of HNBR polymer as the backbone of our HNBR (HSN) o-rings, seals, and packer elements.

Seals Easterns series of formulated HNBR compounds:

Ref#	Duro	Description
7345	70	General service o-ring and packer element rubber.
7346	75	-50C Tg extreme low temperature service rubber.
7336	80	General service o-ring and packer element rubber.
7344	90	High modulus, extrusion resistant, o-ring and packer element rubber.

Technical Papers:

HNBR in CO2

Premium Quality Seals...
For a Cleaner, Safer, More Reliable World.^TM

SRI