How did Teflon come about?

Polytetafluoroethyene will not dissolve in acetone or ether or concentrated sulfuric acid. When Roy Plunkett first found it coating some storage canisters in 1938, he tried to destroy the substance with just about every technique known to science.

A young employee at DuPont, Plunkett had been hired to develop a new refrigerant. But when he cooled and compressed a gas he was testing, a waxy white powder unexpectedly formed—that stuff he couldn’t eradicate. The material was brought to the attention of US Army general Leslie Groves, director of the Manhattan Project, who commissioned DuPont to design a plant that used polytetrafluoroethylene seals and gaskets. (The noxious chemicals needed to produce weapons-grade uranium corroded virtually every other material.)

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.

When Plunkett’s invention was eventually declassified after the war, DuPont gave it the consumer-friendly name Teflon and found a use more compatible with Cold War capitalism: coating pots and pans. The reason your omelet doesn’t stick to Teflon is related to the material’s imperviousness to those A-bomb ingredients. PTFE is a polymer—a long chainlike molecule—made of carbon and fluorine atoms. The fluorine bonds so strongly to the carbon backbone that other atoms can’t break in, so they simply slide across the surface. In fact, the biggest challenge is getting Teflon to adhere to the pan itself. The details of that process are held as closely as the nuclear codes. 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.

Teflon as a consumer product is interesting on its own. A Frenchman named Marc Grégoire was looking for something to keep his fishing gear from getting tangled and discussed Teflon with his wife Collette. She went one better and suggested that nonstick pans would be more useful. They called the coating “Tefal” and started production in 1954. The early French advertisement said, “Nothing sticks to Tefal.” The majority of pots and pans sold in the United States today are coated with one of Teflon’s cousins.

Soon Teflon revolutionized the plastics industry. In 1976, a scientist named Robert Gore co-invented a technique to expand PTFE and bind it into microstructures called Gore-Tex. This led to other applications such as stain-repellant solutions for carpets, clothing and furniture. It is also found in plumber’s tape because it creates watertight seals in pipe joints. Because of its heat-bearing properties, it is used in O-rings and bearings, and as heavy-duty insulation for electronic wiring and cables. These characteristics make it perfect for coating barrels and bottles that contain corrosive industrial materials. Finally, PTFE is an essential component of dental floss!

Teflon was used for military nose cone material on proximity bombs and in artillery shell fuses. Its best asset for these applications: it was transparent to radar. One of the other military uses was in the production of nuclear material used in the Manhattan Project, America’s top-secret plan to build an atomic bomb.

Other uses sprang up, such as in the suits that astronauts wore. For example, as part of the U.S. Apollo program, astronauts donned thick pressure suits that had 25 layers of fabric and plastic. The outer layer was created from Teflon fibers that not only stopped from friction and wear, but also acted as a protectant against fire.

Even though Roy Plunkett was known for his discovery of Teflon, he later went into management at DuPont, eventually becoming the Director of Operations, Freon & Organic Chemicals Division. He retired in 1975, after almost 40 years of service in Wilmington, Delaware.

Check out my related post: Do you know the “Edison of Medicine”?

Interesting reads:


4 thoughts on “How did Teflon come about?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s