The discovery of polytetrafluoroethylene, (PTFE) was accidentally made by Roy Plunkett working for Kinetic Chemicals in 1938 on April 6th. Roy was using the gas, tetrafluoroethylene in a the manufacture of a new refrigerant. During one experiment the pressure of the gas bottle containing tetrafluoroethylene stopped flowing before its weight signalled that it was empty. The gas could not have just disappeared so Roy out of curiosity sawed the bottle apart.
Inside the bottle was a white waxy substance that was slippery to the touch. Instead of dismissing the finding, Roy sent this material for analysis. The results showed that it was a polymerised perfluoroethylene, (that is many groups of perfluroethylene joined together by chemical bonds), and it was surmised that the iron inside the gas container acted like a catalyst under high pressure.
Kinetic Chemicals decided to patent this new fluorinated plastic in 1941 and registered the Teflon trademark in 1945. An early use for Teflon was as a material to coat the valves and seals in pipes at the K-25 uranium enrichment plant Oak Ridge, Tennessee that held the highly reactive uranium hexafluoride. This is because as well as being slippery, Teflon is non-reactive. Another use of Teflon is as a lubricant. Its slippery nature reduces friction, wear and energy consumption in machinery.
By 1948, DuPont, the founder of Kinetic Chemicals was producing over 900 tons of Teflon per year. At this time though, it had not been introduced to the kitchen so people still needed to know how to fry an egg without it sticking to the fry pan. I argue that this is an important skill to have regardless!
Teflon is used as a coating on pans and other cookware including utensils. Its non-reactive properties and heat resistance makes it an ideal coating. The first Teflon coated pan was produced in 1954 by French engineer, Marc Grégoire under the brand name Tefal after his wife urged him to try the material he was using on his fishing tackle on her cooking pans. In 1961, American inventor, Marion A Trozzolo who had been using Teflon on scientific equipment marketed the first USA made Teflon coated frying pan, dubbed “The Happy Pan“.
The coefficient of friction of plastics is measured against polished steel. Teflon’s coefficient friction is 0.05-0.10 which makes it the third lowest of any known solid material. It means that Teflon is very slippery and this slipperiness is due to a resistance to van der Waals forces. It is so slippery that it is the only known surface to which a gecko cannot attach to.