Carboxylated Nitrile

Description

Carboxylated Nitrile, or XNBR, is produced by adding a carboxylic acid side group to nitrile rubber, thereby adding more crosslinking sites than traditional NBR. As a result, solvent swell and abrasion resistance are significantly improved, as well as modulus, tensile strength and tear resistance. However, XNBRs give a higher hardness (up to 12 to 16 durometer points in most recipes) than comparable non-carboxylated NBRs, so care must be taken during the compounding and mixing stages in order to achieve the desired hardness. Water resistance, resilience and some low temperature properties are somewhat diminished.

Composition

Physical Properties*

	Excellent	Good	Fair	Poor
Abrasion resistance	•
Compression Set			•
Elongation		•
Flame resistance				•
Gas permeability		•
Low temperature flexibility			•
Tear resistance		•
Tensile strength	•

Chemical Resistance*

	Excellent	Good	Fair	Poor
Amines				•
Dilute acids and bases		•
Esters				•
LP Gas	•
Oxidation		•
Petroleum oils and fuels	•
Silicone Fluids	•
Solvents		•
Steam			•
Water			•
Weather			•

Operating Temperature

-30 to 250 °F

*Excellent, good, fair and poor are intended to serve as general guidelines only. Actual testing in the application environment is always recommended.