In 1936 he was hired as a research chemist by E.I. du Pont de Nemours and Company at their Jackson Laboratory in Deepwater, New Jersey. The discovery of Teflon is best described in Plunkett's own words:
On the morning ofApril 6, 1938, Jack Rebok, my assistant, selected one of the TFE cylinders that we had been using the previous day and set up the apparatus ready to go. When he opened the valve — to let the TFE gas flow under its own pressure from the cylinder — nothing happened...We were in a quandary. I couldn't think of anything else to do under the circumstances, so we unscrewed the valve from the cylinder. By this time it was pretty clear that there wasn't any gas left. I carefully tipped the cylinder upside down, and out came a whitish powder down onto the lab bench. We scraped around some with the wire inside the cylinder...to get some more of the powder. What I got out that way certainly didn't add up, so I knew there must be more, inside. Finally...we decided to cut open the cylinder. When we did, we found more of the powder packed onto the bottom and lower sides of the cylinder.
Plunkett further relates that the cylinders of TFE being used contained about 1 kg each which would be relatively small, lecture bottle sized cylinders, not large cylinders. The tetrafluoroethylene in the container had polymerized into polytetrafluoroethylene, a waxy solid with amazing properties such as resistance to corrosion, low surface friction, and high heat resistance. Plunkett related the story of this accidental discovery at the spring meeting of the American Chemical Society national meeting in the History of Chemistry section, April 1986 in New York City which was published in the Symposium Proceedings. He was the chief chemist involved in the production of tetraethyllead, a gasoline additive, at DuPont's Chambers Works from 1939 to 1952. After that he directed Freon production at DuPont before retiring in 1975.
Awards
Plunkett received the John Scott Medal from the city ofPhiladelphia in 1951, for an invention promoting the "comfort, welfare, and happiness of human kind". Attendees were given a Teflon-coated muffin tin to take home. Other awards and honors followed. Plunkett was inducted to the Plastics Hall of Fame in 1973 and the National Inventors Hall of Fame in 1985. Plunkett died of cancer on May 12, 1994 at his Texas home at the age of 83.
