EPDM rubber and natural rubber differ in the sense that EPDM is a 100% man-made material whereas NR is a plant-based material that is harvested. EPDM rubber sheeting is made of a blend of strengthening chemicals while natural rubber is made from the latex sap found in rubber trees. These different components used in their production gives each elastomer their own physical and chemical properties. However, because EPDM is a synthetic rubber, an EPDM part will be stronger and will be able to withstand harsher chemicals and environments than a natural rubber part. The unique blend of chemical compounds used to create EPDM rubber sheeting gives it enhanced durability, especially in the face of outdoor conditions, making EPDM rubber one of the best outdoor rubber options available.

Is EPDM Natural Rubber?

EPDM is not a natural rubber, but rather a synthetic rubber made using a blend of multiple chemical compounds that give it excellent physical and chemical properties. Synthetic rubber is defined as “any artificial elastomer. Synthetic rubber is usually derived from additional polymers of polyene monomers and, unless the synthetic rubber is disclosed as a polysulfide rubber, laminates containing such a layer will be classified with additional polymers” (byjus.com). On the other hand, natural rubber is obtained naturally and is “made up of solid particles suspended in a milky while liquid (called latex) that drips from the bark of certain tropical and subtropical trees” (byjus.com). This blend of chemicals gives EPDM rubber a higher level of resistance to ozone and direct sunlight giving it a longer outdoor life. EPDM, also known as ethylene propylene diene monomer, derives from chemicals, including ethylene, propylene, and diene monomers, which gives EPDM rubber its unique physical and chemical properties. EPDM rubber sheeting “have excellent heat, ozone/weathering, and aging resistance. They also exhibit excellent electrical insulation, compression set, and low temperature properties, but only fair physical strength properties. Their resistance to chemicals is generally good” (polymerdatabase.com). These physical and chemical properties of EPDM rubber make it a more resilient and long-lasting material that is the recommended outdoor rubber for outdoor industrial settings.

What is EPDM Made of?

Unlike natural rubber, which is harvested from plants, EPDM rubber is made of a blend of chemical compounds. This unique blend of chemicals dictates the physical and chemical properties of the elastomer. Synthetic EPDM rubber is produced “by copolymerizing ethylene and propylene, usually in combination with other chemical compounds” (Britannica.com). This process creates double-bonds within its chemical backbone which allows it to resist the damaging effects of outdoor conditions and will not be affected by ozone cracking. EPDM rubber can contain varying levels of ethylene and propylene in their composition that dictates their flexibility. For instance, the “usage of high ethylene content will produce polymers with high green strength, whereas low and medium values will produce softer and more elastic polymers” (researchgate.net). In addition, these chemical compounds create a flexible and weather-resistant material that is used in industrial settings, both indoors and outdoors.

What is the Difference Between EPDM and Natural Rubber?

The main difference between synthetic EPDM rubber and natural rubber are their physical and chemical properties which are dictated by the different materials used in their production processes. Natural rubber, as its name implies, is an organic, plant-based material that is harvested from a tree called Hevea brasiliensis. EPDM rubber sheeting, contrarily, is a synthetic, man-made material that is a blend of polymerized chemical compounds. The difference in origins produces materials that have different physical and chemical properties. Industrial EPDM and natural rubber can both be used as general-purpose rubber materials – retaining a high level of abrasion-resistance, high tensile strength, and low compression set while also being flexible elastomers. EPDM is best used as an outdoor rubber or in industrial applications natural rubber cannot withstand. Natural rubber, contrarily, is best suited for light to medium-duty applications that does not involve abrasive temperatures or overly corrosive chemicals. Overall, their main difference can be seen through their physical properties and the environments those properties allow.

Comparing Physical Properties

EPDM is best known for being an outdoor rubber due to its outstanding resistance to outdoor damaging factors, such as ozone, UV rays, and oxidation. Natural rubber will become damaged when exposed to ozone or UV rays for extended periods of time. Because natural rubber is organic and does not contain the same chemicals used in the production of synthetic EPDM rubber, it is highly susceptible to ozone cracking. For example, “Rubber surfaces contains many flaws, where cracks can be initiated via ozone attack. Increasing stress will increase the number of flaws, which leads to a larger number of cracks… Ozone has high reactivity. Every ozone molecules react with a chain of polymer molecules and break the chain” (scienctdirect.com). Both EPDM and natural rubber has a high tensile strength, low compression set, excellent surface friction, and good shock absorption properties which allows both materials to be used in industrial settings; however, an EPDM part will be adaptable to more settings due to its outdoor resistance. EPDM is the ideal outdoor rubber that is a more versatile material capable of being used both indoors and outdoors without degrading after exposure to outdoor environments.

Comparing Chemical Properties

Both industrial EPDM and natural rubber have excellent chemical-resistance properties that allow them to provide protection against certain chemicals and solvents. An industrial natural rubber part is generally resistant to most organic salts, ammonia, acids, and alkali solutions. On the other hand, an industrial EPDM part will have excellent resistance against anti-freeze, synthetic detergents, acetone, boric acid, ethanol, formaldehyde, mercury, potassium sulfate, silver nitrate, saccharin, and even steam. Furthermore, an EPDM part will have a wider operating temperature range of -40 degrees Fahrenheit to 212 degrees Fahrenheit. This wide operating temperature range coupled with excellent chemical-resistance makes EPDM rubber sheeting a popular material for making industrial seals and gaskets. Although both elastomers hold a high degree of chemical resistance, EPDM rubber is best used as outdoor rubber or as heavy-duty materials for abrasive applications whereas natural rubber is better suited for light to medium-duty applications that do not involve overly abrasive chemicals and temperatures.

EPDM rubber sheeting is a popular material used in industrial settings and is commonly used to create durable industrial rubber products, such as an EPDM part, whether it be a seal, gasket, or pad. Its unique blend of various chemicals, including ethylene and propylene, give the elastomer excellent physical and chemical properties that make it the ideal outdoor rubber material. Natural rubber, as its name implies, is made using natural plant-based materials that give its excellent chemical and physical properties, but because EPDM rubber is a synthetic material, it will retain better properties as well as being an overall stronger material. An industrial EPDM part will outlast rubber parts made of natural rubber materials and will provide long-lasting and reliable applications in both indoor and outdoor industrial settings.