EPR (EPM) – This is short for Ethylene Propylene rubber, and is very closely related to EPDM (Ethylene Propylene Diene Monomer). They are functionally the same thing. EPR is often recommended for steam, water, and automotive brake fluids.
E refers to ethylene, P to propylene and M refers to the classification in ASTM standard D-1418. There are two slight difference in EPR and EPDM.
There are very few performance differences between EPR and EPDM. Both of them swell a great deal in petroleum products and both are excellent in water, steam, polar solvents, and acetone. There are some differences in extreme applications: EPR is very tightly cured, EPDM is suited for the nuclear industry and for application that involve concentrated acetic acid. Some EPDM compounds show superior performance to most EPRs, while in other applications, this is almost no difference.
EPR has a temperature range of -50°F to 160°F. It has good tear resistance, good to excellent abrasion resistance and fair to good resilience.
You can find additional technical information related to this and other materials regarding chemical compatibility, resistance to abrasion, suitability for dynamic or static applications, temperature operating ranges, longevity, and other factors on our Technical Information pages.