Guide to the Chemical Resistance of Rubber
The chemical resistance of rubber refers to its ability to work in contact with a given substance without breaking down, swelling or hardening. A wrong material choice causes premature failure of seals and parts. This guide explains the chemical behaviour of the main elastomers.
What determines chemical resistance
Resistance depends on the polymer structure of the material. Polar elastomers work better with polar substances (water, glycerine), while non-polar elastomers work better with oils and fuels. Temperature, concentration and contact time also affect the outcome.
Behaviour of the main materials
EPDM
Excellent resistance to acids, alkalis, hot water, steam, ozone and UV. However, it is incompatible with mineral oil, gasoline and petroleum products. More: what is EPDM rubber.
NBR
Excellent resistance to oil, gasoline, diesel and lubricants. This is why it is widely used in automotive and hydraulics. Weak against ozone and UV. More: oil-resistant NBR rubber.
Viton (FKM)
Offers the broadest resistance to aggressive chemicals, solvents, fuels and high temperature. It is expensive, so it is used only where required.
Silicone
Resistant to high and low temperature and ozone, but weak against oils and solvents; it is more often used in food and medical fields. More: silicone rubber applications.
Quick comparison table
| Medium | EPDM | NBR | Viton |
|---|---|---|---|
| Mineral oil | Poor | Excellent | Excellent |
| Acid/alkali | Excellent | Medium | Good |
| Steam/hot water | Excellent | Poor | Medium |
| Solvents | Poor | Medium | Excellent |
What to consider when choosing
- List all substances that will be in contact, not just the main one.
- State the operating temperature and concentration.
- Indicate whether the contact is continuous or short-term.
In the NUR KAUÇUK laboratory we tailor the material to your application. Review our products or contact us to select the right material.