Ethylene-propylene-diene terpolymers (EPDM) have a fully saturated polymer backbone that gives compounds based on these polymers outstanding resistance to oxygen, ozone, heat and weathering. These inherent characteristics lead to a wide variety of outdoor and under-the-hood applications.
The non-polar nature of EPDM provides resistance to many non-hydrocarbon fluids such as alcohols, glycols, ketones and phosphate esters that make EPDM the choice for coolant hose, brake parts and hydraulic fluid handling. Freedom from ionic impurities leads to the use of EPDM in wire and cable insulation compounds.
The good low temperature properties of EPDM are useful in many outdoor applications. They provide low temperature impact resistance to polypropylene, enabling these blends to be made into thermoplastic vulcanizates (TPV).
In tire and tube applications, blends of EPDM with general purpose rubbers can provide ozone resistance without the used of additives that cause discoloration and staining. EPDM is also useful in increasing the uncured or “green” strength of butyl inner tubes.
Royalene® polymers are also used for viscosity index improvers (VII) to manufacture multi-weight motor oils.