Cut a pipe in half at the right moment

Roy Plunkett (New Carlisle, Ohio, June 26, 1910 – Corpus Christi, Texas, May 12, 1994)

On the morning of April 6, 1938, Roy Plunkett arrived at the laboratories of Du Pont de Nemours in New Jersey as he did every day. He was 28, had just completed his chemistry degree two years ago, and was tasked with developing a new, non-toxic refrigerant for refrigerators.

A few days earlier, he had filled a metal tube with tetrafluoroethylene, a little-used gas that might have cooling properties.

His assistant had just removed the lid from the tube when he entered. "Nothing comes out at all," said the man. "Strange," Plunkett said, "we'll have to look into that." Could there be a valve stuck in the cylinder?

They pulled a wire through the tube, but it turned out to be completely open.

Plunkett decided to weigh the cylinder. A genius idea, as it turned out. The tube was indeed 60 grams heavier than normal. There was nothing for it but to saw them in half.

Plunkett afterwards: 'I was stunned, I said 'gee whiz', something went wrong.' There was a greasy, waxy, white powder on the wall of the tube. Nobody knew what it was.

The firm transferred the investigation to a department more experienced in this sort of thing, and Plunkett returned to all sorts of refrigerants. His colleagues started experimenting with the substance, carried out all possible tests with it and guess what?

The substance was inert, it did not react to anything, not to the strongest acids, not to heat – up to plus 260 degrees Celsius – or not to cold – down to minus 240 degrees; and not electricity. It was stainless and no solvent could dissolve it.

She was also extremely slippery, even slippery than the slipperiest substance in nature: wet ice against wet ice. They called the substance Teflon: 'tef' (their abbreviation for tetrafluoroethylene) and 'lon' because all kinds of plastics at Du Pont carried that suffix: perlon, orlon and nylon, for example.

Teflon also did not react to uranium and was also a dream tool to strengthen the closures of the atomic bomb. Until 1946, the substance was therefore a US state secret. The human body did not reject the substance either.

So that today anything and everything is made of Teflon: artificial cornea, hips and knee joints, parts of the ear, or windpipes, heart valves and tendons.

Plunkett worked on refrigerants until his retirement in 1975. Because he had come up with the idea in his younger years to saw a tube with strange content in half, he was showered with fame.

He was inducted into the Plastics Hall of Fame in 1973 and the National Inventors Hall of Fame in 1985, the highest honor an American inventor can achieve. In 1986, the DuPont company built a new Teflon factory in Mechelen, Belgium. It is also named after Roy Plunkett.

The tefal pan

After the Second World War, scientific research in Europe came to a complete standstill. Under the Marshall Plan, the US government distributed samples of Teflon to a number of government-owned companies in the Allied countries.
In France it ended up with Onera, a predecessor of the aircraft manufacturer Aerospatiale. That's where aerospace engineer Marc Grégoire (1906-1996) saw it. His widow Colette Grégoire said after his death: 'Marc was interested.

He knocked on the door of Du Pont de Nemours' office in Paris to ask if they also had Teflon in liquid form. DuPont turned out to have only a few grams in stock. “It serves no purpose, by the way,” they said. “It doesn't stick to anything.”'

Marc Grégoire was an avid fisherman and was looking for ways to strengthen his fishing line with Teflon. He invented a telescopic fiberglass fishing line with Teflon as an amplifier. But sales did not go smoothly.

Georgette Grégoire: 'If there was one thing he knew absolutely nothing about as an engineer, it was about pots and pans, the kitchen.

One day we were in the kitchen looking at a pan of boiling milk - which burns easily - when I suggested using Teflon against this burning. This is how the idea was born to stick Teflon on aluminum (Tef-Al).

Marc Grégoire crafted the first tefal frying pan in his own garden using traditional methods. It was used only by Madame Grégoire. Grégoire called on his friend and chemical engineer Louis Hartmann.

They took an aluminum surface and used hydrochloric acid to create numerous, very fine grooves that allowed the Teflon to adhere.

Together they took out their first patent in 1954. They produced on a small scale and Georgette demonstrated the pans at fairs, fairs and department stores. In 1956, the two engineers founded their company Tefal SA in Sarcelles, Val d'Oise, and hired their first employee.

In 1958 one million pans were shipped, in 1960 almost three million. In 1968, SEB, a small domestic appliance company, acquired Tefal. If you want to see Mrs. Grégoire's primal tefalpan with your own eyes, you should visit the Du Pont de Nemours museum in Wilmington, Delaware.