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Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene, and has numerous applications because it is chemically inert. [3] The commonly known brand name of PTFE-based composition is Teflon by Chemours , [ 4 ] a spin-off from DuPont , which originally invented the compound in 1938. [ 4 ]
In 1938, polytetrafluoroethylene (DuPont brand name Teflon) was discovered by accident by a recently hired DuPont Ph.D., Roy J. Plunkett. While working with tetrafluoroethylene gas to develop refrigerants, he noticed that a previously pressurized cylinder had no pressure remaining. In dissecting the cylinder, he found a mass of white solid in a ...
[29] [30] Examples include 5-fluorouracil, flunitrazepam (Rohypnol), fluoxetine (Prozac), paroxetine (Paxil), ciprofloxacin (Cipro), mefloquine, and fluconazole. Introducing the carbon–fluorine bond to organic compounds is the major challenge for medicinal chemists using organofluorine chemistry, as the carbon–fluorine bond increases the ...
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene is commonly recognized under the brand name Teflon. PTFE is hydrophobic: aqueous liquids do not wet the material, as fluorocarbons demonstrate mitigated London dispersion forces due to the high electronegativity of fluorine. This also supports its use in coatings ...
A convenient, safe method for generating TFE is the pyrolysis of the sodium salt of pentafluoropropionic acid: [6]. C 2 F 5 CO 2 Na → C 2 F 4 + CO 2 + NaF. The depolymerization reaction – vacuum pyrolysis of PTFE at 650–700 °C (1,200–1,290 °F) in a quartz vessel – is a traditional laboratory synthesis of TFE.
For example, Dyneema, PTFE, Polyester, and Teflon are used for implants. The material type varies depending on the implant area; for example, Polytetrafluoroethylene is preferred for stent implants due to its non-stick properties, while polyolefin is used for mesh implants.
Polytetrafluoroethylene (PTFE), better known by its trade name Teflon, has many desirable properties which make it an attractive material for numerous industries. It has good chemical resistance, a low dielectric constant, low dielectric loss, and a low coefficient of friction, making it ideal for reactor linings, circuit boards, and kitchen utensils, to name a few applications.
A study performed by Giarratana et al. [35] describes a large-scale ex-vivo production of mature human blood cells using hematopoietic stem cells. The cultured cells possessed the same haemoglobin content and morphology as native red blood cells. The authors contend that the cells had a near-normal lifespan, when compared to natural red blood ...