Teflon

Plunkett was 27 years old and two years out of his PhD. DuPont had him chasing safer refrigerants, the same project that had already produced Freon. Tetrafluoroethylene was supposed to be one more candidate gas. He had made a batch, packed it into small steel cylinders, and chilled them overnight on dry ice. On the morning of April 6, he opened a valve to draw gas into his reaction setup. Almost nothing came out. The cylinder still felt full in his hand. A lazier chemist would have written it off as a leak.

He weighed it. The mass matched a full cylinder. He weighed an identical empty one. The math said something solid was inside, but tetrafluoroethylene was a gas, and gases do not just vanish into wax. Plunkett sawed the cylinder in half. The inner surface was caked with a slick white powder. He scraped some out and tested it. It would not dissolve in anything he tried. It would not melt at temperatures that destroyed other plastics. Acids ignored it. The gas had polymerized against the iron walls into long, tightly bonded chains. He named it polytetrafluoroethylene. PTFE.

DuPont patented it in 1941 under Plunkett's name. For years almost nobody could think what to do with a substance that refused to react with anything. Then the Manhattan Project needed gaskets and seals that could survive uranium hexafluoride, one of the most corrosive gases ever handled. PTFE was the only material that held. It went into the bomb program and stayed classified for the rest of the war. Useful, but invisible.

The frying pan took longer. In 1954, a French engineer named Marc Gregoire coated an aluminum pan with PTFE at his wife's suggestion. He sold it as Tefal. DuPont followed with Teflon cookware in the United States in 1961. Sixteen years after Plunkett cut open that cylinder, the residue he had scraped out by hand was being bonded to the bottom of skillets in a billion kitchens.

The refrigerant was never made. The wax on the wall was the product.