EPDM: Ethylene-propylene-diene rubber

Short Name
Ethylene-propylene-diene rubber
EM - Elastomers
General Properties
Chemical Formula
Structural Formula


Glass Transition Temperature
-55 to -30 °C
Melting Temperature
-20 to 60 °C
Melting Enthalpy
5 to 20 J/g
Decomposition Temperature
470 to 487 °C
Young's Modulus
2 to 10 MPa
Coefficient of Linear Thermal Expansion
180 *10¯6/K
Specific Heat Capacity
1.80 to 2.00 J/(g*K)
Thermal Conductivity
0.26 W/(m*K)
0.86 g/cm³
Rubber, sometimes with soft and hard segments
General properties
Very good electrical insulating properties. Very good ozone and sunlight resistance. Good aging resistance. Good resistance to heat, chemicals, hot water and water vapor
Cross-linking by means of sulfur (with accelerators) or peroxides
Seals and profiles. Cable sheathings and insulations. Cool water hoses. Components of household appliance. Construction sealing strips. Blend partners in PP-EPDM blends (TPV) to improve the impact strength of PP (application in the automobile industry as underbody or bumper material)

Internet Links

NETZSCH Measurements

DSC 204 F1 Phoenix®
Sample Mass
13.83 mg
Isothermal Phase
7 min
Heating/Colling Rates
10 K/min
Al, pierced
N2 (40 ml/min)


This EPDM sample is not purely amorphous since it exhibits a small melting transition at 6°C (peak temperature, 2nd heating, green) with an enthalpy of 0.8 J/g, indicating a small amount of crystalline content. The glass transition at -54°C (midpoint, both heatings) is from the amorphous content. The endothermal effect with peak temperatures of 43°C and 52°C (2nd heating, green) is probably due to the melting of additives. This appears as a single peak in the 1st heating (blue).

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