EPDM TerminologyEPDM is a terpolymer of ethylene,propylene and small percentage of nonconjugated diene. Diene provides unsaturation in side chains pendent from the fully saturated backbone.EPDM compounds usually contain carbon black, zinc oxide, antioxidants, processing aids, petroleum based plasticizers and curing ingredients.Rubber grades with higher ethylene content can be more easily processed and more highly loaded with fillers and oils. But this results in products with inferior ‘Low Temperature Properties’ and ‘High Compression Set’.Other properties, particularly compression set, high temperature performance and low temperature flexibility, are highly dependent on the formulation and polymer composition.EPDMs can be cured with peroxides or conventional sulphur cure systems.Sulfur-cured EPDM compounds have high compression set and are less resistant to high temperatures.Peroxide cured compounds exhibit excellent heat aging properties and resistance to compression set up to 150 C.Peroxide-cured EPDM grades with low ethylene content have a service temperature range from -40 to +150 C and short exposures to even higher temperatures.Peroxide-cured EPDM can be vulcanized by LCM line only, to comply with compression set properties as per DIN 7863.Peroxide-cured EPDM can deliver compression set performance for decades.Peroxide-cured EPDM are ideal for applications requiring ‘Good High Temperature Performance’ and ‘Low Compression Set’ e.g. Architectural Sealing Products in harsh climate areas of the world.Vulcanized Rubber PropertiesVulcanized EPDM have fair tensile strength over a wide hardness range and excellent resistance to ozone, weathering and chemical attack. Furthermore, they exhibit very good electrical insulation properties.EPDM Vulcanizates are resistant to the followingNon petroleum based automotives brake fluidsAryl and alkyl-aryl phosphate esters.Hot water and steam up to 200 C with peroxide cured vulcanizatesAqueous solutions of inorga ...