What is PTFE?
PTFE is short for polytetrafluoroethylene, the chemical name for Teflon.
PTFE is a durable, non-stick, and heat-resistant plastic that is widely used in cookware, notably for non-stick pans, and in industrial applications requiring high chemical resistance. Virtually all non-stick cookware sold in the U.S. is coated with PTFE.
The basic building blocks of PTFE are tetrafluoroethylene molecules, which are polymerized to form a long chain of fluorinated carbon atoms. The resulting strands of PTFE are extruded, rapidly cooled, and chopped into fine powder. This powder is then sintered at high temperatures to form a solid mass that can be molded or machined into various shapes.
PTFE was first synthesized in North America in the late 1930s by DuPont chemists who were exploring new fluorinated materials. DuPont later branded its PTFE product as “Teflon.”
What are the properties of PTFE?
The strong C-F chemical structure and high bond energy give PTFE its unique performance properties. Several benefits of PTFE include:
- Wide service temperature range – excellent thermal and thermoxidative resistance (C-F binding energy is higher than C-H bonds)
- Excellent resistance to attack by chemicals, solvents, and acids
- Readily resistant to electrical insulation and dielectric properties
- Excellent non-stick and non-adhesive properties
- Low coefficient of friction
- Flexible at low temperatures
- Opaque appearance
- Excellent mechanical properties (high tensile strength, low elongation)
- Low chemical reactivity
- High bio-compatibility
- Excellent weather resistance (UV, rain, and wind)
PTFE can withstand temperatures (-200°C to 260°C) depending on the duration of exposure. Parts made of PTFE when exposed to chemicals, acids, and UV rays for long periods. This results in virtually no change in physical properties. Unlike most plastics, PTFE is not affected by chemical attacks as well.
What are the limitations of PTFE?
Not all that glitters is gold, and PTFE is no exception. There are some downsides to the use of this material, which include:
Environmental concerns
PTFE is non-biodegradable, making it an environmental pollutant. It induces land pollution because plastic does not disintegrate. It causes air pollution because when it’s burned, it emits toxic fumes, including perfluorooctanoic acid (PFOA) — highly harmful chemicals to the environment.
Health and safety concerns
Because of the toxic chemicals released by PTFE during its manufacturing process, use, and disposal, it can be a threat to human health.
Toxins like PFOA and other fluorinated compounds cause myriad illnesses such as hormonal imbalances, respiratory health effects, and in extreme cases, cancer.
Heat sensitivity
PTFE has low thermal stability, making it heat sensitive. When subjected to consistently high levels of heat, it degenerates.
Manufacturers can improve its heat stability by introducing certain stabilizers like alumina, silica, and titanium dioxide. These additives prevent the degradation of PTFE when exposed to heat.
What are the main applications of PTFE?
PTFE is one of the most commonly used fluoropolymers. Its combination of chemical resistance, non-stick properties, together with its overall safety, make it extremely popular in the food and medical spaces. Additional examples of PTFE applications include:
- Aerospace. PTFE’s resistance to high temperatures and chemicals makes it a good material for use in aerospace applications, including in protective coating, wire insulation, and fuel system components.
- Automotive. Just as with aerospace, PTFE’s properties allow it to be a great material in the automotive industry as well. It is often found in gaskets, fuel lines, and various seals and bearings.
- Construction. PTFE’s chemical resistance together with its durability make it a strong choice for construction uses. This includes coatings, waterproof membranes, and sealing materials.
- Medical. Many PTFE recipes are FDA approved, making it a safe material to use for different types of medical equipment, including catheters, sutures, surgical meshes, and tubing.
- Food packaging and processing. As with its use in the medical industry, PTFE is used for food packaging and processing due to its overall safety and non-stick properties. It is often found in various cookware, conveyor belts, and packaging films.
- Electronics. PTFE is found in many electronics, often used in insulation, connectors, and coatings for various circuits, cables, and components in a range of different electronic devices.
Is PTFE safe for humans?
PTFE has both potential benefits and disadvantages for the environment.
PTFE is extremely durable, so it can reduce the need for frequent material changes, thereby reducing waste.
Due to its chemical inertness, PTFE does not release harmful chemicals, which is beneficial to the environment.
Of course, due to its high energy consumption and non-degradability, the pressure it puts on the environment cannot be underestimated.
Is Teflon and PTFE the same thing?
We can give a short answer to this: there is absolutely no difference.
This is because PTFE is the usual abbreviation for polytetrafluoroethylene, and Teflon® is one of the many brand names of this plastic. Over time this brand name has become generic as ‘Teflon’. Just think of Velcro, a manufacturer of hook-and-loop fasteners, the name of which has become synonymous with these types of fasteners.