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Encyclopedia > PTFE

Teflon is the brand name of a polymer compound discovered by Roy J. Plunkett (1910-1994) of DuPont in 1938 and introduced as a commercial product in 1946.


Teflon is polytetrafluoroethene (PTFE).

 F F | | R - C - C - R | | F F 

Teflon is also used as the trade name for a polymer with similar properties, perfluoroalkoxy polymer resin (PFA):

 F F F F | | | | R - C - C - C - C - R | | | | F F F O | F - C - F | F 

Teflon has the lowest coefficient of friction of any solid material known to man. It is used as a non-stick coating for pans and other cookware. Teflon is very unreactive, and so is often used in containers and pipework for reactive chemicals. Its melting point is 327 °C.


Teflon is sometimes said to be a spin-off from the US space program with more down-to-earth applications, but actually its first significant use was in the Manhattan Project, as a material to contain highly-reactive uranium hexafluoride. It was first sold commercially in 1946.


Teflon has been supplemented with another DuPont product, Silverstone, a three-coat fluoropolymer system that produces a more durable finish than Teflon. Silverstone was released in 1976.


Amongst many other industrial applications, Teflon is used to coat certain types of hardened, armour-piercing bullets, so as to reduce the amount of wear on the firearm's rifling. These are often mistakenly referred to as "cop-killer" bullets on account of Teflon's supposed ability to ease a bullet's passage through bullet-proof armour. Any armour-piercing effect is, however, purely a function of the bullet's velocity and rigidity rather than a property of Teflon.


Teflon has been implicated in cancer, though DuPont denies any association.


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  Results from FactBites:
 
Fuel cell membrane electrode assemblies with improved power outputs and poison resistance - Patent 6300000 (18806 words)
The Pt/skived PTFE was hot pressed against the membrane to bond the Pt evaporated layer to the membrane by the decal method.
The electrocatalyst zone was coated at a deposition rate averaging 6.ANG./sec as measured with a vibrating crystal microbalance to the specified target loading, with a magnetron power ranging of 250-500 W, 490-570 V dc bias, and 450-900 mA Ar.sup.+ flux.
Electrode elements such as ELAT gas diffusion media and 6 mil skived PTFE sheets were placed in a vacuum chamber.(1.5 m diameter, 2 m long) which was pumped down to ca.
Fluorotherm - Properties (326 words)
Melt Temperature: PTFE - Does not melt, softens at 625 deg F, FEP - 500 deg F
PTFE, being a homopolymer, has the best thermal and best chemical resistance compared to copolymers.
In general PTFE has a tensile strength 15% to 20% lower than FEP; however, this difference may narrow at higher operating temperatures due to the higher sensitivity of FEP to increase to temperature.
  More results at FactBites »

 

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