Environmental Pollutants
Other Contaminants Teflon Research Center
|
Learn More About DuPont's Teflon
Teflon is the brand name of a compound that was discovered by Roy J. Plunkett (1910-1994) of DuPont in 1938 and introduced as a commercial product in 1946. Teflon's chemical name is polytetrafluoroethylene, or PTFE, which is a polymer of fluoride and ethylene.
PTFE has the lowest coefficient of friction of any solid. It is used as a non-stick coating for cookware. PTFE is very unreactive, and so is frequently used in containers and pipework for reactive chemicals. Its melting point varies between 260 °C (FEP) and 327 °C (PTFE), depending on the specific Teflon polymer in question.
PTFE is sometimes described as a spin-off from the US space program with more everyday applications. But this is untrue as teflon cooking pans were commonplace before Yuri Gagarin's flight in 1961. PTFE was discovered serendipitously by Roy Plunkett of DuPont in 1938, while attempting to make a new CFC refrigerant, when the perfluorethylene polymerized in its storage container. DuPont patented it in 1941, and registered the Teflon trademark in 1944.
Its first significant use was in the Manhattan Project, as a material to contain highly-reactive uranium hexafluoride, when it was known as K416.
It was first sold commercially in 1946 and by 1950, DuPont was producing over a million pounds (450 t) per year in Virginia.
Teflon has been supplemented with another DuPont product, Silverstone, a three-coat fluoropolymer system that produces a more durable finish than Teflon. Silverstone was released in 1976.
Amongst many other industrial applications, PTFE is used to coat certain types of hardened, armor-piercing bullets, to minimize the amount of wear on the firearm's rifling. These are often inccorectly referred to as "cop-killer" bullets because of PTFE's purported ability to ease a bullet's passage through body armor. Any armor-piercing effect is, however, purely a function of the bullet's speed and rigidity rather than a property of PTFE.
PTFE has excellent electrical properties especially at radio frequencies, making it highly suitable for use in insulation in cables and connector assemblies. Coupled with its high melting temperature, this makes it the material of choice as a substitute for the weaker polyethylene which is frequently used in low-cost applications.
Due to its low friction, it is used for applications where sliding action of parts is needed e.g., bearings, gears, slide plates, etc. In these applications, it performs significantly better than nylon and acetal; it is comparable with UHMWPE, where teflon displays lower resistance to wear than UHMWPE. For these applications, versions of teflon with mineral oil or molybdenum disulfide embedded as additional lubricants in its matrix are being made.
Gore-Tex is a material incorporating teflon membrane with micropores.
Harm from Teflon
Teflon exposure has been linked to cancer, although DuPont denies any such connection. Non-stick coatings on househould frying pans have also been shown to release toxic gases upon overheating. These gases are lethal to avians, and can cause flu-like symptoms in humans. This polymer fume fever in humans may last for more than a week in cases of moderate household exposure. This level of exposure can occur when a Teflon pan is left unattended on a high-power gas burner in a small unventilated apartment. In more severe cases, the decomposition chemicals can be fatal. In recent years, facing the possibillty of litigation, DuPont has become more forthcoming about the risks of using Teflon on hot surfaces but has not stopped selling the product.
The EPA's scientific advisory board found in 2005 that perfluorooctanoic acid, a chemical compound used to make Teflon, is a "likely carcinogen." DuPont settled for $300 million in 2004 a lawsuit filed by residents near its manufacturing plant in Ohio and West Virginia based on groundwater pollution from this chemical. Currently this chemical is not regulated by the EPA
see also:
PFOA
Find your Teflon Perfluorooctanoic Acid (PFOA) lawsuit attorneyDid Perfluorooctanoic Acid (PFOA) in Teflon cause your cancer?
News & Warnings
Teflon Lawsuit - Free Resource Center- News & Warnings - DuPont TeflonDuPont Teflon Lawsuit News, Warnings and Information
Research Center
DuPont Teflon Research Center - Learn dangers & how a lawyer can helpCancer causing DuPont Teflon and your health: Fight back with a lawyer
