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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.
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 liquid VF is suspended in water and stabilized either by water-soluble polymers based on cellulose or polyvinyl alcohol. Inorganic salts can also act as stabilizers. The suspension polymerization is usually initiated by organic peroxides (eg diisopropyl peroxydicarbonate), but UV light or ionizing radiation can also be used.
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. The process is however ...
Water-reactive substances [1] are those that spontaneously undergo a chemical reaction with water, often noted as generating flammable gas. [2] Some are highly reducing in nature. [ 3 ] Notable examples include alkali metals , lithium through caesium , and alkaline earth metals , magnesium through barium .
In addition to PFPE, Krytox grease also contains telomers of PTFE and in fact was designed as a liquid or grease form of PTFE. It is thermally stable, nonflammable (even in liquid oxygen), and insoluble in water, acids, bases, and most organic solvents. It is nonvolatile and useful over a broad temperature range of −75 to 350 °C (−100 to ...
Experts say vehicle-based attacks are simple for a 'lone wolf' terrorist to plan and execute, and challenging for authorities to prevent.
water-vapour barriers for protecting phosphor coatings in electroluminescent lamps (the phosphor chemicals are sensitive to moisture) protection of liquid-crystal display (LCD) panels, which are sensitive to moisture; Due to its chemical stability, it acts as a protective barrier against chemicals.