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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 ]
Polymeric organofluorine compounds are numerous and commercially significant. They range from fully fluorinated species, e.g. PTFE to partially fluorinated, e.g. polyvinylidene fluoride ([CH 2 CF 2] n) and polychlorotrifluoroethylene ([CFClCF 2] n). The fluoropolymer polytetrafluoroethylene (PTFE/Teflon) is a solid. [citation needed]
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.
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.
The material consists of PTFE powder that has been compressed into solid forms and sintered for stability, with approximately 40 percent void volume [clarification needed] to enhance scattering of light. [6] Surface or subsurface contamination may lower the reflectance at the extreme upper and lower ends of the spectral range.
Polymer fume fever or fluoropolymer fever, also informally called Teflon flu, is an inhalation fever caused by the fumes released when polytetrafluoroethylene (PTFE, known under the trade name Teflon) reaches temperatures of 300 °C (572 °F) to 450 °C (842 °F).
PCTFE is a homopolymer of chlorotrifluoroethylene (CTFE), whereas PTFE is a homopolymer of tetrafluoroethylene. The monomers of the former differs from that of latter structurally by having a chlorine atom replacing one of the fluorine atoms. Hence each repeating unit of PCTFE have a chlorine atom in place of a fluorine atom.
Furthermore, cells release reactive oxygen species and cytokines, which cause secondary damage to surrounding tissue. [17] These chemical factors then proceed to promote the recruitment of other immune responsive cells such as monocytes or white blood cells, which help foster the formation of a blood clot and protein-rich matrix. [citation needed]