One morning in April 1938, 27-year-old DuPont chemist Roy J. Plunkett cracked open the valve of a pressurized canister containing tetrafluoroethylene (TFE) gas in preparation for an experiment. Much to his irritation, the canister that he had filled the night before appeared to be empty. His assignment had been to find a replacement for the refrigerant Freon 114, on which Frigidaire currently held a monopoly. To conduct his scheduled experiment that morning, he needed to release some TFE into a heated chamber and then spray in hydrochloric acid.
Plunkett, Roy J.
One of the most versatile and familiar products of American chemical engineering, Teflon, was discovered by accident. There are many such tales to be found in the history of industrial chemistry, from vulcanized rubber to saccharin to Post-Its, all of which were stumbled upon by researchers looking for other things. So common, in fact, are unplanned discoveries of this sort that one might expect would-be inventors to simply mix random chemicals all day long until they come up with something valuable.