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Roy J. Plunkett
Teflon®

In 1938, Roy J. Plunkett capitalized on an accident and invented one of the best known and most widely used polymers of all time: Teflon®.

Plunkett's first assignment, as a research chemist at DuPont's Jackson Lab in Deepwater, New Jersey, was synthesizing new forms of the DuPont refrigerant Freon®. His work moved along methodically until April 6, 1938. On that day --- as happens so often in the annals of invention --- a mistake led to a discovery, which led in turn to a great invention.

What seems to have happened is this. Plunkett and his technician assistant, Jack Rebok, were testing the chemical reactions of the refrigerant gas tetrafluoroethylene (TFE). One pressurized cylinder of the gas, which they themselves had filled earlier, failed to discharge when its valve was opened. They set the cylinder aside, but Rebok later noticed it was too heavy to be empty, and suggested they cut it open to see what had gone wrong. Plunkett agreed, despite the risk of an explosion; and they discovered that the gas inside the cylinder had inexplicably solidified into a white powder. Intrigued, Plunkett put his scheduled work aside and began to test the properties of this substance. It was much more lubricant than other slippery solids, like graphite; and in addition, it proved inert to virtually all other chemicals and had an extremely high melting point.

In time, Plunkett found that the gas had polymerized (that is, its molecules had bonded), becoming polytetrafluoroethylene (PTFE) resin. Its unique properties were caused by an impenetrable shield of fluorine atoms which lock onto and protect the compound's essential string of carbon atoms. More importantly, Plunkett invented a way to reproduce the TFE-to-PTFE polymerization in the lab.

The next year, Plunkett became supervisor of Du Pont's tetraethyl lead production, while the Plastics division refined his production process for the PTFE resin. By 1941, PTFE had both a patented process and a trade name: Teflon®. In 1946, the first products were sold: machine parts for military and industrial applications. In the early 1960s, Teflon® found its most famous use, as a seemingly miraculous nonstick surface for cookware. Today, Teflon® is used as a coating for myriad metals, fabrics and wires, but also as a plastic in its own right. Indeed, Teflon® has expanded into a whole family of polymers, found in industries as varied as aerospace and pharmaceuticals, and sold in over forty countries world-wide.

When he retired from Du Pont in 1975, Roy J. Plunkett had guided their development of numerous fluorochemical products, for virtually every field of manufacturing. Still, his induction into the National Inventors' Hall of Fame (1985), and the many other honors of his later years, were due above all to the curiosity and follow-through that gave the world its slipperiest synthetic solid.

[July 2000]