Plastics are often viewed as sensitive materials that melt when exposed to a heat source. This assumption is incorrect; in fact, a wide range of high-performance plastics offer a continuous service temperature of up to 500 °F. In this article, we will discuss our top 5 high-performance heat-resistant plastics as well as their respective applications.
"Although some plastics have limited heat resistance, many of them remain efficient when subjected to high temperatures.”
Alex Tremblay Frenette, Eng.
Heat-resistant plastics: myth or reality?
Contrary to popular belief, many polymers have high melting points and are designed to perform in harsh conditions. In other words, they can be exposed to high heat without compromising their mechanical properties. These plastics are therefore suitable for highly specialized applications, offering a wide range of interesting options.
Here are our top 5 heat-resistant plastics:
PTFE or Teflon (polytetrafluoroethylene)
Better known as PTFE or "Teflon," polytetrafluoroethylene possesses some impressive characteristics. Its coefficient of friction ranges between 0,05 et 0,10, the lowest of all plastics. This interesting feature combined to its extraordinary heat resistance makes it one of the most versatile plastics on the planet. Click here to learn more about friction reduction.
PTFE is also recognized for its ability to withstand high temperatures even in its virgin form, i.e., without additives or fillers. It can be continuously exposed to temperatures of up to 500 °F (260 °C) without losing its mechanical properties. This remarkable polymer is also chemically inert, which means it can be exposed to acids, aggressive cleaning products and corrosive agents without damage. Thanks to these interesting particularities, PTFE is a material of choice for environments where high temperatures, chemical products and friction are present. Moreover, it is also available in food grade.
What about PTFE with additives?
Additives are substances that are added to the base resin of a polymer to modulate its properties. As for PTFE, it can be enhanced with additives that improve some of its properties.
PTFE Graphite: The addition of graphite greatly improves mechanical properties, particularly by increasing wear resistance.
PTFE Carbon: This carbon-filled version allows PTFE to be more resistant to wear and compression while adding antistatic properties.
PAI (Polyamide imide)
Polyamide imide or PAI is an advanced material that easily adapts to the most demanding environments. Even in its virgin form, this rigid plastic has mechanical properties that surpass those of numerous metals. Frequently used in environments where temperatures reach extreme highs, it retains its properties and efficiency even when subjected to continuous service temperatures of up to 518 °F (270 °C). PAI also has excellent dimensional stability due to its high resistance to compression, impact and creep.
Polyetherimides are a family of high-performance plastics with excellent thermal properties. ULTEM® is by far the most frequently used PEI. Easily recognizable by its translucent, amber-coloured appearance, this material is used by the chemical and healthcare industries in advanced applications. It is also a prized material for the production of electrical components.
Combining excellent chemical and thermal resistance, PEI is ideally suited for applications that come into contact with highly corrosive products and where operating temperatures reach up to 340 °F (171 °C). This performance polymer can also withstand aggressive cleaning and frequent sterilization cycles.
Polyetheretherketone, commonly known as PEEK, is the product of research, development and technological advances. It is undoubtedly one of the most complete polymers in terms of properties. With excellent mechanical and chemical resistance, it performs well and retains its properties even when exposed to continuous temperatures of up to 482 °F (250 °C). Thanks to its tolerance to sterilization cycles, this food-safe material is frequently used in the medical industry as well as industries where constraints require the use of high-performance plastics.
PEEK is available in two forms: virgin or containing enhancing additives such as glass, carbon and graphite.
UHMW with high heat resistance
This family of materials is known for its great versatility. Combining advantageous mechanical properties and excellent wear resistance, UHMW can be used in a variety of applications (anti-friction liners, wear strips, mechanical parts and much more). Unfortunately, UHMW is rarely used when designing heat resistant parts. This is unfortunate, as some UHMWs are specifically developed to withstand high temperatures. The best example is UHMW TIVAR H.O.T., a material that possesses all the mechanical properties of standard UHMW but remains efficient even when continuously exposed to temperatures of up to 275 °F (135 °C).
Thanks to their light weight, chemical resistance, heat resistance and ability to reduce friction, these high-performance plastics can be used in an array of applications.
Industries that benefit from heat-resistant plastics:
- Medical and pharmaceutical
- Aviation and aerospace
Examples of applications:
- Bearings and ball bearings
- Mechanical parts
- Laboratory and medical instruments
- Food machinery components
- Heat resistant liners
- Valves and pumps
- Conveyor parts and components
What about cold temperatures?
For material subjected to extremely low temperatures, resistance to cold is often essential. However, a plastic that withstands heat is not necessarily adequate for low temperatures. In cases like these, it would be wise to choose a plastic that can face large temperature variations. Some of the materials presented in this article are excellent choices for cold environments because they offer a wide range of operating temperatures.
PTFE is the perfect example of a plastic able to endure extreme temperatures, both hot and cold. As mentioned earlier, it can operate in temperatures of up to 500 °F (260 °C) but can also tolerate conditions as low as -328 °F (-200 °C).