.

Wednesday, November 6, 2019

Roy Plunkett and the Invention of Teflon

Roy Plunkett and the Invention of Teflon Dr. Roy Plunkett discovered PTFE or polytetrafluoroethylene, the basis of Teflon ®, in April 1938. It’s one of those discoveries that happened by accident. Plunkett Discovers PTFE Plunkett held a Bachelor of Arts degree, a Master of Science degree, and his PhD in organic chemistry when he went to work at the DuPont research laboratories in Edison, New Jersey. He  was working with gases related to Freon ®Ã‚  refrigerants when he stumbled upon PTFE. Plunkett and his assistant, Jack Rebok, were charged with developing an alternative refrigerant and came up with tetrafluorethylene or TFE. They ended up making about 100 pounds of TFE and were faced with the dilemma of storing it all. They placed the TFE in small cylinders and froze them.  When they later checked on the refrigerant, they found the cylinders effectively empty, even though they felt heavy enough that they should still have been full. They cut one open and found that the TFE had polymerized into a white, waxy powder polytetrafluoroethylene or PTFE resin. Plunkett was an inveterate scientist. He had this new substance on his hands, but what to do with it? It was slippery, chemically stable and had a high melting point. He began playing with it, attempting to find out if it would serve any useful purpose at all. Ultimately, the challenge was taken out of his hands when he was promoted and sent to a different division. The TFE was sent to DuPont’s Central Research Department. The scientists there were instructed to experiment with the substance, and Teflon ® was born. Teflon Properties The molecular weight of Teflon ® can exceed 30 million, making it one of the largest molecules known to man. A colorless, odorless powder, it is a fluoroplastic with many properties that  give it an increasingly wide range of uses. The surface is so slippery, virtually nothing sticks to it or is absorbed by it – the Guinness Book of World Records once listed it as the slipperiest substance on earth. It’s still the only known substance that a geckos feet cant stick to.   The Teflon Trademark PTFE was first marketed under the DuPont Teflon ® trademark in 1945.   No wonder Teflon ® was chosen to be used on non-stick cooking pans, but it was originally used only for industrial and military purposes because it was so expensive to make. The first non-stick pan using  Teflon ® was marketed in France as Tefal in 1954. The U.S. followed with its own Teflon ®-coated pan the Happy Pan in 1861. Teflon Today Teflon ® can be found just about everywhere these days: as a stain repellant in fabrics, carpets and furniture, in automobile windshield wipers, hair products, lightbulbs, eyeglasses, electrical wires and infrared decoy flares. As for those cooking pans, feel free to take a wire whisk or any other utensil to them – unlike in the old days, you won’t risk scratching the Teflon ® coating because its been improved. . Dr. Plunkett stayed with DuPont until his retirement in 1975. He died in 1994, but not before being inducted into the Plastics Hall of Fame and the National Inventors’ Hall of Fame.

No comments:

Post a Comment