Teflon, a tradename of DuPont, is most closely associated with the fluoropolymer, polytetrafluoroethylene (Varilla de PTFE). With its exceptional release (non stick), low friction or dry lubrication, PTFE is one of the most widely recognize compounds use throughout the world. In fact, its uses are almost endless.

Formed by free radical vinyl polymerization of tetrafluoroethylene (TFE), Varilla de PTFE is recognize for its high thermal stability. Continuous service temperatures of 500 F are typical, though higher temperatures can satisfactorily sustained for shorter duration.

Mechanical properties include flexibility at low (cryogenic) temperatures, abrasion resistance and mechanical toughness. Keep in mind that wear factors can dramatically improved by internal or external material reinforcements. This is especially true using PTFE dispersions.

Non-lubricated mechanical systems have reported coefficients of friction as low as 0.02-0.04. Even at higher dynamic PV limits, (8,000 to 10,000) coefficients of friction of 0.10 or less are attainable. Results will vary with load, rates of travel, distance, surface finish, temperature, and other system-dependent parameters. PTFE resins exhibit exceptionally low friction (in otherwise non-lubricated environments), at lower surface velocities, pressures greater than 5 pounds per square inch. Curiously, friction actually increases with sliding speed up to 100 feet per minute, under all pressure conditions. But it’s this phenomenon that prevents ‘stick-slip’ tendencies. Other benefits include ‘anti-squeak’ or ‘no noise’ even at the highest speeds. Above 150 feet per minute, for example, sliding velocity has little effect (on friction) at combinations of pressure and velocity below the composition’s PV limit. Static friction of Dupont Teflon PTFE resins decrease with increasing pressure.

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