Polytetrafluoroethylene (PTFE), more commonly known as Teflon today, was discovered accidentally in a DuPont laboratory more than 80 years ago.
One of the most commonly used polymers in recent decades, PTFE was the result of an attempt by Roy Plunkett of the New Jersey laboratories of DuPont to make a new chlorofluorocarbon refrigerant. During this process the tetrafluoroethylene gas in its pressure bottle stopped flowing before the bottle’s weight had dropped to the point of signalling ‘empty’.
When Plunkett measured the amount of gas by weighing the bottle, he became curious about the source of the weight. Upon sawing the bottle apart, he noticed a waxy and slippery white coating on the inside. On analysis, the substance was shown to be perfluoroethylene.
Kinetic Chemicals patented the new fluorinated plastic in 1941, and registered the Teflon trademark in 1945.
By 1948, DuPont, which formed Kinetic Chemicals in partnership with General Motors, was producing over 900 tons of Teflon brand PTFE each year. Over the next decade, Teflon was used as coating for non-stick cookware and quickly became a household name with patented brands such as Tefal and Happy Pan.
Thanks to its excellent dielectric properties, especially at high radio frequencies, it was used as an insulator in connector assemblies and cables as well as in printed circuit boards used at microwave frequencies.
PTFE has a broad industrial application too thanks to its low friction and high chemical resistance; it is used for bushes, washers, gaskets, seals, slide plates, valve seats and tooling pins among many more.
Allplastics Engineering has been machining PTFE components over the last 44 years for a diverse range of industries including food, packaging, pharmaceutical, chemical, materials handling and transport.
For special applications where virgin PTFE is not suitable, Allplastics can provide glass filled, carbon filled and bronze filled PTFE. If the PTFE is required to be bonded to steel, a chemically etched surface can be requested on one side of the sheet.
Key features of PTFE include superior chemical resistance; high temperature use up to 260°C; lowest co-efficient of friction; physiologically inert material; excellent electrical properties; and ability to deform (flow) under high loads.