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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.
Polychlorotrifluoroethylene (PCTFE or PTFCE) is a thermoplastic chlorofluoropolymer with the molecular formula (CF 2 CClF) n, where n is the number of monomer units in the polymer molecule. It is similar to polytetrafluoroethene (PTFE), except that it is a homopolymer of the monomer chlorotrifluoroethylene (CTFE) instead of tetrafluoroethene.
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 ...
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.
But buzz is building around so-called "Teflon flu" after a growing number of people have reported getting sick from using pans coated with polytetrafluoroethylene (PTFE), aka Teflon.
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.
A polymer is a substance composed of macromolecules. The latter usually have a range of molar masses (unit g mol −1), the distributions of which are indicated by dispersity (Đ). It is defined as the ratio of the mass-average molar mass (M m) to the number-average molar mass (M n) i.e. Đ = M m /M n. [4]