PTFE Non Stick Coating
PTFE non stick coating (polytetrafluoroethylene) is probably the most common solution to preventing sticking in cookware today. But what about your engineered equipment or tool? Want to learn more?
Often identified as Dupont Teflon, its non stick properties are exceptional.
PTFE is a completely fluorinated polymer, manufactured by free radical polymerization of tetrafluoroethylene. With a linear molecular structure of repeating -CF2-CF2- units, PTFE has dielectric strength, and is a crystalline polymer with useful mechanical properties from cryogenic temperatures to 500 degrees Fahrenheit. High temperature can be satisfactorily sustained for shorter exposures.
The key to PTFE non stick coating performance is derived from richly electronegative fluorine atoms, which repel one another, but repel other atoms even more.
Impact strength is high, while tensile strength, wear resistance, and creep resistance are significantly enhanced through various resin binders, ceramic, fillers or other structural reinforcement.
Thus, the PTFE non stick coating is offered in almost limitless arrays of thermoplastics. Property enhancements can include for release, load bearing capacity, lower friction, mechanical strength, and a host of other properties.
The PTFE non stick coating is highly resistant to oxidation and action of chemicals including strong acids, bases, oxidizing agents, nuclear radiation, UV rays, and ozone.
Mechanical properties include, but are not limited to, flexibility at low temperatures, stability at high temperatures (also known as ‘hot hardness’) low coefficient of friction, dielectric strength, corrosion resistance, and, of course, non stick (release).
When considering DuPont products, PTFE, in non stick applications, sometimes you need to consider creep and cold flow. Generally, a plastic material subjected to continuous load experiences a continued deformation with time called creep or cold flow. Deformation can be significant, even at room temperature or below; hence, the name ‘cold flow’.
Most applications requiring release, however, are more closely associated with lower loads. Also, the PTFE non stick coating is typically a resin bonded system, so issues relating to compressive recovery, original strain and yield strain, should be irrelevant. Especially when harder surfaces are required. Because, then, PTFE raw dispersion is typically offered as an integrated form with plating, anodizing, thermal spray, and other emerging composites or advanced processing techniques.