Plunkett’s Eureka! Moment
In 1938, two years after Roy Plunkett joined the giant American chemical company, he was still looking for the company’s safe refrigerant. The current inherent chemicals –ammonia and sulfur dioxide-- were still too dangerous for use in the home.
Plunkett started using a chemical called tetrafluoroethylene or TFE that was compressed into tanks. He once stored the chemical overnight in dry ice to keep the gas from expanding too much and exploding. When nothing came out of the tank during the cooling-fluid experiment the next day, Plunkett assumed that the gas had leaked out. The only way to check his theory was to put it on a scale and weigh it. Funny, but the tank weighed the same as when it was full.
He and an assistant tried to unclog the valve to the tank with a long wire thinking it was stuffed up and prevented the substance from coming out. Nothing. Finally, Plunkett decided to open the tank and unscrewed the lid. A bunch of white waxy flakes fell out. He and his assistant sawed the tank in half, and the inside of the tank was coated with the same slippery stuff. The material had polymerized.
Plunkett surmised that the tiny gas molecules had joined to make a long chain so he named it “polytetrafluoroethylene" (PTFE).
Deciding to examine the waxy substance, Plunkett put it under some tests. He later told his wife that he was initially disappointed, thinking the experiment a complete flop. When he made a decision to test the material anyhow, he attacked it with a vengeance. He heated and froze it. Then he began digging in the cupboard to find chemicals to check its other properties.
In addition to being slippery, the glob was unfazed by other powerful chemicals, and unchanged by searing acids. The best part though, came after he dipped a plastic rod covered with the stuff into an acid. The rod dissolved in the corrosive material but did not change the white waxy coating. It also had a low surface friction so it would not stick to anything.
DuPont christened it Teflon and trademarked it in 1945. Plunkett was awarded the patent for it in 1941. Plunkett would later tell students that his mind had been prepared for the challenge by years of education, and that he had succeeded because he was trained to recognize novelty.