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Tetrafluoroethylene (TFE) is a fluorocarbon with the chemical formula C 2 F 4. ... The depolymerization reaction – vacuum pyrolysis of PTFE at 650–700 °C ...
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]
Depolymerization is a very common process. Digestion of food involves depolymerization of macromolecules, such as proteins. It is relevant to polymer recycling. Sometimes the depolymerization is well behaved, and clean monomers can be reclaimed and reused for making new plastic. In other cases, such as polyethylene, depolymerization gives a ...
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.
Depolymerizable polymers or Low-Ceiling Temperature Polymers refer to polymeric materials that can undergo depolymerization to revert the materials to their monomers at relatively low temperatures, such as room temperature. For example, the ceiling temperature T c for formaldehyde is 119 °C, and that for acetaldehyde is -39 °C. [1] [2]
At the ceiling temperature, the enthalpy term and the entropy term are equal, so that the rates of polymerization and depolymerization become equal and the net polymerization rate becomes zero. [1] Above the ceiling temperature, the rate of depolymerization is greater than the rate of polymerization, which inhibits the formation of the given ...
Depolymerization is favored at high temperatures: TΔS p is large. As the temperature increases, ΔG p become less negative. At a certain temperature, the polymerization reaches equilibrium (rate of polymerization = rate of depolymerization). This temperature is called the ceiling temperature (T c). ΔG p = 0. [24]
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 quantity similar to that of the tetrafluoroethylene gas. It was determined that this material was a new-to-the-world polymer. Tests ...