The low friction of the PTFE makes the socks exceptionally smooth, protecting feet from blisters. PTFE was discovered accidentally in by a young scientist looking for something else. Roy Plunkett was a chemist for E. He had earned a PhD from Ohio State University in , and in when he stumbled upon Teflon, he was still only 27 years old. Plunkett's area was refrigerants. Many chemicals that were used as refrigerants before the s were dangerously explosive.
Du Pont and General Motors had developed a new type of non-flammable refrigerant, a form of Freon called refrigerant Refrigerant was tied up in an exclusive arrangement with General Motor's Frigidaire division, and at the time could not be marketed to other manufacturers.
Plunkett endeavored to come up with a different form of refrigerant that would get around Frigidaire's patent control. The technical name for refrigerant was tetrafluorodichloroethane. Plunkett hoped to make a similar refrigerant by reacting hydrochloric acid with a compound called tetrafluoroethylene, or TFE.
TFE itself was a little known substance, and Plunkett decided his first task was to make a large amount of this gas. The chemist thought he might as well make a hundred pounds of the gas, to be sure to have enough for all his chemical tests, and for toxicological tests as well.
He stored the gas in metal cans with a valve release, much like the cans used commercially today for pressurized sprays like hair spray. Plunkett kept the cans on dry ice, to cool and liquefy the TFE gas. His refrigerant experiment required Plunkett and his assistant to release the TFE gas from the cans into a heated chamber. On the morning of April 6, , Plunkett found he could not get the gas out of the can. To Plunkett and his assistant's mystification, the gas had transformed overnight into a white, flaky powder.
The TFE had polymerized. Polymerization is a chemical process in which molecules combine into long strings. One of the best known polymers is nylon, which was also discovered by researchers at Du Pont. Polymer science was still in its infancy in the s. Plunkett believed that TFE could not polymerize, and yet it had somehow done so. He sent the strange white flakes to Du Pont's Central Research Department, where teams of chemists analyzed the stuff.
The polymerized TFE was curiously inert. It did not react with any other chemicals, it resisted electric currents, and it was extremely smooth and slick.
Plunkett was able to figure out how the TFE gas had accidentally polymerized, and he took out a patent for the polymerized substance, polytetrafluoroethylene, or PTFE. But it came into use in World War II, during the development of the atomic bomb.
Making the bomb required scientists to handle large amounts of the caustic and toxic substance uranium hexafluoride. Du Pont provided PTFE-coated gaskets and liners that resisted the extreme corrosive action of uranium hexafluoride.
Du Pont registered the trademark name Teflon for its patented substance in , and continued to work after the war on cheaper and more effective manufacturing techniques.
The company marketed Teflon after the war's end as a coating for machined metal parts. In the s, Du Pont began marketing cookware coated with Teflon. The slick Teflon coating resisted the stickiness of even scorched food, so cleaning the pans was easy.
The company marketed Teflon for a variety of other uses as well. DuPont patented the new fluorinated plastic and registered the Teflon trademark in It was first introduced to the public in as Teflon-coated non-stick frying pans and cookware.
Coupled with its high melting temperature, PTFE is the perfect high-performance substitute for the weaker and lower-melting-point polyethylene typically used in low-cost electrical applications. PTFE makes longer-lasting, higher-performance parts that reduce friction, wear, and energy consumption of machinery, lower maintenance costs, and increase the lifetime of both parts and machinery.
Due to its high temperature rating and extreme non-reactivity, PTFE is often used as containers, expansion joints, liners in hose assemblies, industrial pipelines, and other applications involving corrosive and reactive chemicals.
Call us today at to put our expertise to work for you! Thermoset or thermosetting plastics. Once cooled and hardened, these plastics retain their shapes and cannot return to their original form. They are hard and durable. Thermosets can be used for auto parts, aircraft parts and tires. Examples include polyurethanes, polyesters, epoxy resins and phenolic resins. Less rigid than thermosets, thermoplastics can soften upon heating and return to their original form.
They are easily molded and extruded into films, fibers and packaging. PET is a thermoplastic that can be drawn into fibers like Dacron and films like Mylar. It's the main plastic in ziplock food storage bags. Polystyrene Styrofoam : Polystyrene is formed by styrene molecules.
The double bond between the CH2 and CH parts of the molecule rearranges to form a bond with adjacent styrene molecules, thereby producing polystyrene. It can form a hard impact-resistant plastic for furniture, cabinets for computer monitors and TV s , glasses and utensils. When polystyrene is heated and air blown through the mixture, it forms Styrofoam. Styrofoam is lightweight, moldable and an excellent insulator. When made, it's brittle, so manufacturers add a plasticizer liquid to make it soft and moldable.
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