R. J. Plunkett discovered Teflon in 1983 at the du Pont Jackson laboratory. A tetrafluoroethylene cylinder was cut open with a welding torch after it failed to deliver a flow of gas, and upon comparing its weight to that of an empty cylinder, it was discovered to weigh more.

Features
Teflon tapes have high melting points and an extremely low coefficient of friction. It withstands corrosive environments in a chemical plant such as gaskets, rings, tubing and taps. It provides a leak proof seal for pipe threads. self-lubricating with excellent dielectric properties which minimize galvanic action. The tape protects against any corrosive action and is not affected by weather. It does not harden, crack or crumble. It is chemically inert and usable at low temperatures.

Teflon undergoes ‘cold flow’. It changes its dimension when pressure is applied. Teflon tape is wrapped around the threads of the screw and the polymer flows in a way to seal empty space, which would otherwise create fluid leaks during high-pressure applications

Applications
The high-density Teflon tape is the best sealant available and is specified by many industrial users, utilities, and government agencies. Easy to use for sealing all types of threaded pipe, valves, fittings, accessories and controls, including those made from steel, galvanized and black iron, brass, copper, aluminum, stainless steel, glass, monel, synthetic rubber, and all plastics. Appropriate for pipes carrying acids, solvents, alkalis, steam, hot and cold water, natural gas, oxygen and almost every chemical.

It is used in a fluid mill. Fluid mill shakes corundum cylinders to grind a coal sample for an analytical test. The Teflon tape keeps all the water in the plastic container during the shaking process. It is used to seal air lines and gas lines.