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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 ]
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.
One of the most commonly used copolymers is P(VDF-trifluoroethylene), usually available in ratios of about 50:50 and 65:35 by mass (equivalent to about 56:44 and 70:30 molar fractions). Another one is P(VDF-tetrafluoroethylene). They improve the piezoelectric response by improving the crystallinity of the material.
PTFE has a higher melting point and is more crystalline than PCTFE, but the latter is stronger and stiffer. Though PCTFE has excellent chemical resistance, it is still less than that of PTFE. [22] PCTFE has lower viscosity, higher tensile strength and creep resistance than PTFE. [1] PCTFE is injection-moldable and extrudable, whereas PTFE is ...
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 ...
The number average molar mass is a way of determining the molecular mass of a polymer.Polymer molecules, even ones of the same type, come in different sizes (chain lengths, for linear polymers), so the average molecular mass will depend on the method of averaging.
Their low mass combined with their square or flat packaging means you can place more in a shipping container and spend less fossil fuel transporting them.
Fluorinated ethylene propylene was invented by DuPont and is sold under the brandname Teflon FEP. Other brandnames are Neoflon FEP from Daikin or Dyneon FEP from Dyneon / 3M . FEP is very similar in composition to the fluoropolymers PTFE (polytetrafluoroethylene) and PFA (perfluoroalkoxy polymer resin) .