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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.
[1] PCTFE has one of the highest limiting oxygen index (LOI). [16] It has good chemical resistance. It also exhibits properties like zero moisture absorption and non wetting. [15] [17] It does not absorb visible light. When subjected to high-energy radiation, it undergoes degradation like PTFE. [18] It can be used as a transparent film. [14]
The molar mass of atoms of an element is given by the relative atomic mass of the element multiplied by the molar mass constant, M u ≈ 1.000 000 × 10 −3 kg/mol ≈ 1 g/mol. For normal samples from Earth with typical isotope composition, the atomic weight can be approximated by the standard atomic weight [ 2 ] or the conventional atomic weight.
For instance u value of ETFE single layer, double and three layers are approximately: 5.6, 2.5 and 1.9 W/m2.k respectively [7] while concerning g value of etfe cushion or SHGC in ETFE systems it can vary between 0.2 to 0.95 using frits [5] and for further info about SHGC in ETFE refer to [8]
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 showed the substance was resistant to corrosion from most acids, bases and solvents and had better high temperature stability than any other plastic.
Therefore, average values are given for the molecular weight like the number average, the weight average or the viscosity average molar mass. A measure for the width of the molecular weight distribution is the polydispersity index.
It has a short half-life, 0.5 and 20 ms, in solution and in the gas phase, respectively. [1] Although highly reactive, difluorocarbene is an intermediate in the production of tetrafluoroethylene , which is produced on an industrial scale as the precursor to Teflon ( PTFE ).