EPDM Rubber Compounds
Ethylene propylene diene monomer, EPDM rubber, offers good low temperature flexibility, high tensile strength, high tear and abrasion resistance and excellent resistance to ozone, water and oxidation. Common uses for EPDM are roofing materials, ditch and pond liners, O-rings, seals, gaskets and weatherstripping, hoses, boots.
Because EPDM is a fully saturated compound, no double bonding between atoms, it is highly resistant to ozone attack and makes it highly suitable for applications that will be exposed to sunlight, weathering, or ozone. However, EPDM rubber is not suitable for use with hydrocarbon (petroleum) oils and greases, natural gas, mineral oils.
The first commercial ethylene propylene (EPM, EPR) was a copolymer of ethylene and propylene but could only be cured with a peroxide cure. With the addition of a third monomer, diene, they were able to use a sulfur cure. Today most ethylene propylene rubber is EPDM with a sulfur cure but is also available with a peroxide cure for increased physical properties. EPDM sulfur cured O-rings are readily available off the shelf and offers a wide temperature range and resistance to polar solvents, keytones, ordinary diluted acids and alkalies, and weathering.
Common Name: EPR, EPT, EPM, EPDM
Chemical Name: Ethylene Propylene Diene Monomer
ASTM D1418 Designation: EPDM
Hardness Range (Shore A): 30-90
Tensile Strength Range (psi): 500-2500
Elongation (Max %): 600
Compression Set: Good
Abrasion Resistance: Good
Tear Resistance: Fair
Solvent Resistance: Poor
Oil Resistance: Poor
Low Temperature: -55°F
High Temperature: 250°F
Aging, Weathering-Sunlight: Excellent
- Exceptionally good weather aging and ozone resistance.
- Excellent water and chemical resistance.
- Excellent resistance to gas permeability and aging due to exposure to steam.
- Good in keytones and alcohols.
- Not recommended for food applications or exposure to aromatic hydrocarbons, hydrocarbon (petroleum) oils and greases, natural gas, mineral oils.