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PTFE as a surface coating

PTFE - polytetrafluoroethylene

Polytetrafluoroethylene (PTFE) is an unbranched, linearly structured, partially crystalline polymer made from fluorine and carbon. Colloquially, this plastic is often referred to by the trade name Teflon from DuPont. Other frequently used trade names by other manufacturers of PTFE are Dyneon PTFE (formerly Hostaflon) and Gore-Tex for PTFE membranes.

PTFE is one of the thermoplastics, although it also has properties that require processing that is more typical for thermoset plastics.

properties

PTFE is characterized by several special features:

  • PTFE is very inert. Even aggressive acids such as aqua regia cannot attack PTFE. The reason is the particularly strong bond between the carbon and fluorine atoms, as fluorine is the element with the strongest electronegativity. Many substances fail to break the bonds and react chemically with PTFE.
  • It is extremely resistant to all bases, alcohols, ketones, benzines, oils, etc .; it is only unstable to very strong reducing agents such as solutions of alkali metals (e.g. sodium) in liquid ammonia or to very strong oxidizing agents such as elemental fluorine at higher temperatures;
    Application temperature up to 150 °C; can only be bonded after pretreatment; welding possible, but not common; slightly waxy surface (not as pronounced as PE); physiologically harmless.
  • There are almost no materials that stick to PTFE because the surface tension is extremely low. PTFE is difficult to wet and hardly sticky. The contact angle with water is 126 °.

Extract from Wikipedia:
(As of July 2013)