Davet, George P. "Using Belleville Springs To Maintain Bolt Preload" (PDF). Solon Mfg. Co. Archived from the original (PDF) on 18 May 2014 . Retrieved 18 May 2014. Emerging Contaminants Fact Sheet – Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA). National Service Center for Environmental Publications (Report). United States Environmental Protection Agency. March 2014. p.1. 505-F-14-001 . Retrieved 10 February 2019. What is the difference between PFOA, PFOS and GenX and other replacement PFAS?". PFOA, PFOS and Other PFASs. EPA. 18 February 2018. Most cases of polymer fume fever in humans occur due to smoking PTFE-contaminated tobacco, [64] although cases have occurred in people who have welded near PTFE components. [64] PTFE-coated cookware is unlikely to reach dangerous temperatures with normal use, as meat is usually fried between 204 and 232°C (399 and 450°F), and most cooking oils (except refined safflower and avocado oils) start to smoke before a temperature of 260°C (500°F) is reached. A 1973 study by DuPont's Haskell Laboratory found that a 4-hour exposure to the fumes emitted by PTFE cookware heated to 280°C (536°F) was lethal for parakeets, although that was a higher temperature than the 260°C (500°F) required for fumes from pyrolyzed butter to be lethal to the birds. [65] PTFE tubing is used for Bowden tubing in 3D printers because its low friction allows the extruder stepper motor to push filament through it more easily.

Corona discharge treatment of the surface to increase the energy and improve adhesion has been reported. [15] Production [ edit ]

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As a result of the lawsuits concerning the PFOA class-action lawsuit, DuPont began to use GenX, a similarly fluorinated compound, as a replacement for perfluorooctanoic acid in the manufacture of fluoropolymers, such as Teflon-brand PTFE. [76] [77] However, in lab tests on rats, GenX has been shown to cause many of the same health problems as PFOA. [78] [79] Beekman, M.; etal. (12 December 2016). "Evaluation of substances used in the GenX technology by Chemours, Dordrecht". National Institute for Public Health and the Environment ( RIVM, The Netherlands) . Retrieved 23 July 2017.

a b c d e "Hazardous Substances Data Bank (HSDB): 833". pubchem.ncbi.nlm.nih.gov. National Center for Biotechnology Information National Library of Medicine . Retrieved 4 April 2022. PTFE is a thermoplastic polymer, which is a white solid at room temperature, with a density of about 2200kg/m 3 and a melting point of 600K (327°C; 620°F). [20] It maintains high strength, toughness and self-lubrication at low temperatures down to 5K (−268.15°C; −450.67°F), and good flexibility at temperatures above 194K (−79°C; −110°F). [21] PTFE gains its properties from the aggregate effect of carbon-fluorine bonds, as do all fluorocarbons. The only chemicals known to affect these carbon-fluorine bonds are highly reactive metals like the alkali metals, and at higher temperatures also such metals as aluminium and magnesium, and fluorinating agents such as xenon difluoride and cobalt(III) fluoride. [22] At temperatures above 650–700°C (1,200–1,290°F) PTFE undergoes depolymerization. [23] Property These retain the useful PTFE properties of low friction and nonreactivity, but are also more easily formable. For example, FEP is softer than PTFE and melts at 533K (260°C; 500°F); it is also highly transparent and resistant to sunlight. [81] See also [ edit ]PTFE architectural membranes are created by coating a woven glass-fibre base cloth with PTFE, forming one of the strongest and most durable materials used in tensile structures. [42] Some notable structures featuring PTFE-tensioned membranes include The O2 Arena in London, Moses Mabhida Stadium in South Africa, Metropolitano Stadium in Spain and the Sydney Football Stadium Roof in Australia.