Ethylene propylene rubber

EPM is considered a valuable elastomer due to its useful chemical and physical properties; it is resistant to heat, oxidation, ozone and the weather (owing to its stable, saturated backbone) and it is also not susceptible to color loss.

[2] As a non-polar compound, EPM is an electrical insulator and it is insoluble in many polar solvents, both protic and aprotic.

EPM has a large number of uses due to the many ways in which the polymer can be designed, for example; it is used in automotive weather-stripping and seals, self-amalgamating tape, glass run channels, radiators, garden and appliance hoses, tubing, belts, roofing membranes, expansion joints, rubber mechanical goods, plastic impact modification, thermoplastic vulcanisates and motor oil additive applications.

EPM is even more prevalent as an insulator for high-voltage cables (usually referred as HEPR - Hard grade Ethylene Propylene Rubber) since it has improved insulative characteristics over more traditional cables, such as cross-linked polyethylene, enabling a smaller cross sectional area for the same load carrying capacity.

A third, non-conjugated diene monomer can be terpolymerized in a controlled manner to maintain an unsaturated backbone ready for vulcanization or polymer modification.