The best rubber materials for high temperature applications

Did you know that excessive heat can gradually erode rubber materials?

Extreme temperatures can lead to a deterioration in performance and, in some cases, premature failure. Natural rubber, for instance, should never be used in applications where the temperature remains at 70 degrees Celsius or 158 degrees Fahrenheit.

So what is the alternative? For applications that are required to be used in high-temperature conditions, synthetic grades of rubber can be chemically engineered to withstand heat in excess of 300 degrees Celsius or 570 degrees Fahrenheit.

If you need a rubber material that is capable of withstanding high levels of heat, then you should consider putting one of these applications to use. But it should always be kept in mind that the mechanical properties will be very different in high temperatures from the values indicated on technical data sheets.

CSM

Chlorosulphonated polyethene rubber, or CSM as it’s more commonly known, is able to resist dry heat to a maximum of 150 degrees Celsius or 300 degrees Fahrenheit. It also responds well against ultra-violet rays, ozone, and corrosive chemicals.

CSM is commonly used in mining operations, chemical processing, mass transit, and other applications that require a fire-resistant material. Typical articles made of CSM include cable sheathing, conveyor belts, handrails for escalators, or tarpaulins and films for water basins. However, it’s not recommended to be used in instances that require fuel resistance as it’s unable to perform well compared to other items.

EPDM

Depending on its cross-linking, this material is capable of resisting heat up to 170 degrees Celsius or 338 degrees Fahrenheit for a short period of time. In continuous use, 130 degrees Celsius or 266 degrees Fahrenheit is realistic for EPDM. EPDM is a copolymer of propylene, ethylene, and diene monomers. In other words, it is a synthetic rubber that not only handles high temperatures but also performs well against abrasions, tears, steam, and compression.

The automotive and engineering industries commonly use EPDM for electrical gaskets, waterproofing sheets, as well as window and door seals. Molded rubber parts such as precision diaphragms or valves used in demanding applications are also made of EPDM. It’s a preferred material both due to its ability to handle general weather conditions, ozone, and UV levels as well as its reasonable mechanical properties.

HNBR

Similar to EPDM, HNBR can withstand heats up to 150 degrees Celsius or 300 degrees Fahrenheit. It’s a unique material in that it’s constructed from traditional nitrile rubber by hydrogenating unsaturated bonds in butadiene. This is what provides its ability to stretch and its superior strength. Unlike HNBR, regular NBR can only be used up to about 110 degrees Celsius or 230 degrees Fahrenheit in continuous service.

You’ll commonly find HNBR used in the automotive industry. It’s primarily used for belts, hoses, as well as static and dynamic seals. Due to its excellent mechanical properties, HNBR is also widely deployed in dynamic applications. Moreover, it is known to be used in industrial sealing for rolls of steel or paper and oil field exploration.

Silicone Rubber

The perhaps most reliable rubber material that can withstand extreme temperatures is silicone rubber. Its compounds are able to resist heat levels of 305 degrees Celsius or 580 degrees Fahrenheit. Unlike other materials, both liquid silicone rubber as well as high consistency silicone retain most of their original properties even when exposed to high heat. However, while it can operate under these conditions, silicone rubber is not a high strength material and is prone to tearing when deployed in dynamic applications. As such, it’s not suitable for certain types of uses.

In general, silicone can be used in many different forms. Silicone is popular for adhesives, sealants, encapsulants, as well as potting compounds for coatings and electronics. It’s also commonly used as a way to transfer thermal energy in heat-generating applications. Rubber molded parts made of silicone rubber typically comprise different kind of gaskets, silicone O-rings, silicone suspensions, and silicone bearings. Silicone is also the most used elastomer material in the medical industry.  

FKM

One of the best rubber materials resistant to heat is FKM. To a wider audience, FKM is known as Viton, marketed by the US chemical company DuPont (now DuPont de Nemours).  It is resistant to many forms of chemicals and keeps its elasticity in temperatures of 220 degrees Celsius or 430 degrees Fahrenheit. FKM is also capable of performing when it’s exposed to conditions of 316 degrees Celsius or 600 degrees Fahrenheit in short periods of time (up to 70 hours).

Due to this unique nature, FKM is used in seals, O-rings, accumulator bladders, hoses, and gaskets that are required to perform in extreme temperatures. It’s also ideal for environments where exposure to chemicals such as mineral acids or petroleum is very common. FKM is even known to be used in the aeronautical industry as it has proven to be reliable when used in these operations.

FFKM

Perfluoroelastomer, or FFKM, is an ideal rubber material for applications that will be challenged under extreme duress. It is known to many by the tradename Kalrez marketed by DuPont de Nemours, FFKM can withstand temperatures up to 325 degrees Celsius or 617 degrees Fahrenheit and is also most compatible with almost every type of chemical.

FFKM is often used in the aerospace, energy, and pharmaceutical industries. It’s used specifically for seals and O-rings that are exposed to environments featuring severe temperatures or exposure to acids, petroleum, or other types of fuel.

Where to Find Rubber Materials That Can Withstand Heat

Understanding your requirements is the first step in deciding the type of rubber materials you may need. Each one has its pros and cons and is appropriate for different kinds of uses. It’s also imperative to know what other elements the rubber material might be exposed to besides heat. This may mean chemicals, mechanical properties, or even certain types of weather conditions.

Fortunately, you don’t need to understand all of the individual properties for yourself or conduct research experiments on your own. Hepako manufactures rubber materials in accordance with your specific requirements. For many businesses around the world, our company is the first contact when precise rubber articles are required. If you need rubber parts for your organisation, get in touch with Hepako today to discuss how we can help you.

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