Selecting nitrile rubber for both oil immersion and low-temperature flexibility

Does oil resistance apply to every oil?

Identify the oil, temperature and contact time. A change in bound acrylonitrile content also warrants reassessment of low-temperature behavior.

Judge immersion and low-temperature performance separately

Use the actual contact fluid and identical immersion conditions. Measure volume change using the same sampling and wiping procedure. Assess flexibility separately at the target low temperature.

Will higher acrylonitrile content improve low-temperature performance too?

Select against a specified cold test and the oil-resistance target together. One structural parameter cannot establish both. Oil-resistant seals: Immerse in the intended oil at service temperature. Record changes in volume, hardness and strength. Hoses and extruded parts: Evaluate the finished part at target pressure, temperature and low-temperature bend conditions.

Checking Bound acrylonitrile and Mooney viscosity

Bound acrylonitrile (% by mass): Report on a polymer basis and state the method. Mooney viscosity (MU): Report test temperature, rotor and duration. Volume change after fluid exposure (%): Keep the medium, immersion time and state of cure constant.

What to record

• Medium
• Contact temperature
• Immersion time
• Volume change
• Low-temperature performance

Technical references

• ARLANXEO: nitrile rubber families and applications ↗

Products and processes