Tetrafluoroethene, polymerization

Tetrafluoroethene polymerizes to form the slippery polymer that is commonly known as Teflon . Teflon M is used as a non-stick coating in frying pans, among other uses. Classify the following polymerization reaction, and name the product. (The letter n indicates that many monomers are involved in the reaction.)... 

Teflon IS made in a similar way by free radical polymerization of tetrafluoroethene... 

Many perfluoroaUphatic ethers and tertiary amines have been prepared by electrochemical fluorination (1 6), direct fluorination using elemental fluorine (7—9), or, in a few cases, by fluorination using cobalt trifluoride (10). Examples of lower molecular weight materials are shown in Table 1. In addition to these, there are three commercial classes of perfluoropolyethers prepared by anionic polymerization of hexafluoropropene oxide [428-59-1] (11,12), photooxidation of hexafluoropropene [116-15-4] or tetrafluoroethene [116-14-3] (13,14), or by anionic ring-opening polymeriza tion of tetrafluorooxetane [765-63-9] followed by direct fluorination (15). 

The monomer reactant of this polymerization reaction contains a double bond. The product polymer has no double bond, so an addition reaction must have occurred. Thus, this reaction is an addition polymerization reaction. Since the monomer s name is tetrafluoroethene, the product s name is polytetrafluoroethene. 

Teflon, discovered accidentally by Roy Plunkett at DuPont, is formed by polymerizing tetrafluoroethene. Teflon has a low coefficient of friction and is remarkably resistant to chemical attack. The ability of Teflon to flow under pressure makes it an ideal sealant for pipe threads and vessels, and... 

Despite the possibly unfavourable thermodynamics for phosgene polymerization, it may be possible to prepare polyphosgene by alternative routes. Poly(carbonyl fluoride), for example, has been prepared from the reaction of tetrafluoroethene with trioxygen (ozone) (see Chapter 13). Alternatively, the co-polymerisation of phosgene with, for example, alkenes may be worthy of investigation [ICI94]. 

TETRAFLUOROETHENE (116-14-3) Highly reactive, thermally unstable, flammable gas (flash point <32°F/<0°C). Explodes under pressure. Able to form unstable peroxides in air. If inhibitor (usually limolene) is not present in adequate concentrations, explosive polymerization may occur above 2025 mm Hg/2.66 bar at normal temperatures. Inhibited monomer will explode on contact with iodine pentafluoride and other substances, or in elevated temperatures. Violent reaction with chloroperoxytrifluoromethane, difluoromethyl-ene dihypofluorite, dioxygen difluoride, halogens, oxidizers, oxygen, sulfur trioxide, triboron pentafluoride. Incompatible with ethylene, hexafluoropropene forms an explosive peroxide. 

Write the structure of tetrafluoroethene. This aUcene polymerizes to form polytetrafluoroethene (PTFE). Write the... 

Teflon is made in a similar way by free-radical polymerization of tetrafluoroethene. Carbon-fluorine bonds are quite strong (slightly stronger than C—H bonds), and like polyethylene. Teflon is a very stable, inert material. We are all familiar with the most characteristic property of Teflon, its nonstick surface. This can be understood by comparing Teflon and polyethylene. The high electronegativity of fluorine makes C—F bonds less polarizable than C—H bonds, causing the dispersion forces in Teflon to be less than... 

C) prepared by the polymerization of tetrafluoroethene under pressure (45-50 atmospheres). The reaction requites an initiator, ammonium petoxosulphate. The polymer has a low coefficient of friction and its anti-stick properties ate probably due to its helical structure with the fluorine atoms on the surface of an inner ting of carbon atoms. It is used for coating cooking utensils and nonlubricated beatings. 

The ultimate product of the polymerization of the CF, unit is the solid known as poly(tetrafluoroethene) or PTFE (Teflon), used in non-stick surface coverings. In the polymer there are C-C linkages between the tetrafluoroethene monomer units. All the atoms obey the octet rule, all the carbon atoms are four-valent, and each of the fluorine atoms participate in one single bond. That the oxidation state of the carbon is +2 is very misleading. 

Teflon is produced from the polymerization of tetrafluoroethene. Write the structure of Teflon showing the monomeric unit in parentheses. 

The polymers, thus simply based on (CF2)n that subsequently come from that monomer are actually produced by the free radical polymerization of the alkene (tetrafluoroethene tetrafluoroethylene, CF2=CF2). They are known, generically, as... 

Bulk polymerization of tetrafluoroethene (TFE) by radiation was studied in the gas, liquid, and solid phase over a wide range of temperatures from —196 to 90 °C by a number of methods (e.g. NMR and FTIR spectroscopy). Volkova et al. [710] studied the radiation-induced polymerization in the gas phase from 12 to 90 °C. Different activation energies were found below and above 70 °C. Enslin et al. [711] reported that the rate of polymerization in the gas phase was a zero-order function of the monomer pressure. However, the rate of polymerization was profoundly influenced by the initial monomer pressure (4.6-order dependence) and on the radiation intensity (0.36-order dependence). 

Teflon is the polymer formed from polymerization of tetrafluoroethene. Here are several useful applications of this wonderful material. 

Two important polymers are manufactured from chlorofluoro-compounds. The mmiomer for the commercially named Teflon or PTFE is C2F4 (tetrafluoroethene) which is prepared by reaction 14.45. Polymerization occurs in the presence of water with an organic peroxide catalyst. Teflon is an inert white solid, stable up to 570 K. It has widespread domestic applications, e.g. non-stick coatings for kitchenware. The monomer CF2=CFC1 is used to manufacture the commercial polymer Kel-F. Both Teflon... 

When the polymer polytetrafluoroethylene is made from the monomer tetrafluoroethene, there is no loss of atoms from each monomer molecule. Classify the polymerization as either addition or condensation. 

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