It was on this day in 1938 that Roy J Plunkett and his technician Jack Rebok, employees at Kinetic Chemicals, accidentally discovered Teflon (polytetrafluoroethylene, aka PTFE).
Plunkett was working on new chlorofluorocarbon refrigerants when the gas in one bottle appeared to be finished, even though the bottle still weighed the same as full bottles. Curious about this, the container was sawn open, and instead of gas, Plunkett & Rebok discovered a slippery, waxy white powder. This was found to be polymerised perfluoroethylene, and further analysis showed the material had some rather unique properties – it was highly hydrophobic, had one of the lowest friction coefficients of any known solid, and was chemically inert with a very high melting point.
Realising they had something special on their hands, the material was patented by DuPont, founding owners of Kinetic Chemicals, and the trademark Teflon was registered in 1945.
Its unique properties has resulted in Teflon finding application in a range of highly disparate domains. Its unusually low friction coefficient means that it is an excellent lubricant in applications requiring dry lubrication, reducing friction, wear and energy consumption in the machinery where it is used. Its chemical inertness makes it an excellent coating material in valves, seals and pipes carrying highly reactive and corrosive chemicals. Its hydrophobic qualities has resulted in it being incorporated as a membrane in Gore-Tex, a popular, breathable waterproofing material. It has been used in thread seal tape, applied to the feet of computer mice, as a coating for bullets and as a highly effective air filtration membrane, among many other applications.
And we all know how pervasive it has become as a non-stick coating for cooking pots and pans, thanks to its hydrophobic properties. Interestingly, the first pans using non-stick Teflon coating, the Tefal range, were developed in 1954 by a French engineer Marc Gregoire, who developed the cookware coating at the recommendation of his wife Collete, who saw him use it on his fishing tackle. (In some countries Tefal is marketed as T-Fal as a result of DuPont’s insistence that ‘Tefal’ sounded too similar to ‘Teflon’.)
It’s probably safe to say that Teflon is one of the most diversely applied modern materials – not bad for a polymer discovered by accident!