Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene and is a PFAS that has numerous applications. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a spin-off from DuPont, which originally discovered the compound in 1938.
Polytetrafluoroethylene is a fluorocarbon solid, as it is a high-molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine. PTFE has one of the lowest coefficients of friction of any solid.
Polytetrafluoroethylene is used as a non-stick coating for pans and other cookware. It is non-reactive, partly because of the strength of carbon–fluorine bonds, so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant, PTFE reduces friction, wear, and energy consumption of machinery. It is used as a graft material in surgery and as a coating on catheters.
PTFE is one of the best-known and widely applied PFAS commonly described as persistent organic pollutants or "forever chemicals". Only since the start of the 21st century has the environmental impact and toxicity to human and mammalian life been studied in depth. For decades, DuPont used perfluorooctanoic acid (PFOA, or C8) during production of PTFE, later discontinuing its use due to ecotoxicological and health issues that led to legal actions. Dupont's spin-off Chemours today manufactures PTFE using an alternative chemical it calls GenX, another PFAS.
Polytetrafluoroethylene (PTFE) was accidentally discovered in 1938 by Roy J. Plunkett while he was working in New Jersey for DuPont. As Plunkett attempted to make a new chlorofluorocarbon refrigerant, the tetrafluoroethylene gas in its pressure bottle stopped flowing before the bottle's weight had dropped to the point signaling "empty".
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Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to its widespread use. Plastics typically are made through human industrial systems.
Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reactive, as it reacts with all other elements except for the light inert gases. Among the elements, fluorine ranks 24th in universal abundance and 13th in terrestrial abundance.
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