Poly tetrafluoro ethylene

Chemical Name poly(tetrafluoro- ethylene) poly(perfluoroalkoxy) resin poly(perfluoroethylene- propylene) poly(chloro- trifluoro- ethylene)... 

The isotope fluorine-18 has a half-life of 110 min if the interval between its preparation and use can be kept short, it might be useful in a number of connections. It has been suggested (48) that 18F-labelled poly-tetrafluoro-ethylene and other fluoro-polymers might be used to determine their very low solubilities, and to study their frictional properties by methods similar to those already used in examination of the lubricating properties of other materials. 

A sensor for organic chloride-containing compounds was constructed by immobilization of luminol or tris (2,2 bipyridyl) ruthenium (III) between a PMT and a poly (tetrafluoro) ethylene (PTFE) membrane [15], through which a stream of air was sampled by diffusion. A heated Pt filament incorporated in the gas line leading to the CL cell was used to oxidize the analytes prior to diffusion across the PTFE membrane. Detection limits for CC14, CHC13, and CH2C12 were 1.2-4 ppm. A similar device could also be used for the determination of hydrazine and its monomethyl and dimethyl derivatives or NH3 vapor. The detection limit for hydrazine was only 0.42 ppb [16]. 

POLYPROPYLENE zPOLYETHYLENE H.D. POLY(TETRAFLUORO ETHYLENE) (Teflon )... 

Poly(tetrafluoro ethylene) Poly(vinyl acetate)... 

Besides scientific names, many polymers are indicated by their common name, trade name, brand name, or abbreviation (commercial names) [4]. Typical examples of common names are nylon or silicone. Several nylons are known and the name nylon 6 is used for poly[imino(1-oxo-1,6-hexandiyl)], the name nylon 66 is used for poly(iminohexa-methyleneiminoadipolyl), etc. Trade names such as Teflon for poly(tetrafluoro-ethylene) made by DuPont, Nomex for poly(iminoisophthaloylimino-1,3-phenylene), or Kevlar for poly(iminoisophthaloylimino-1,4-phenylene) are also common. Many abbreviations are in use for both homopolymers and copolymers. Table 1.2.1 gives some of the common abbreviations for polymers. 

Lattice Visualization of Poly(tetrafluoro ethylene) (PTFE) by CM-AFM Sample Preparation Friction Deposition... 

The generic process for electrochemical synthesis of sp-carbon chains was electrochemical reductive carbonization (corrosion) of poly(tetrafluoro-ethylene) (PTFE) by alkali metal amalgams, pioneered by Jansta and dousek [6 9] (for review see Reference 3). The reaction occurs at the interface of a dry contact between PTFE and alkali metal amalgams, hence, it does not seem to recall an electrochemical synthesis in its classical sense. The purely electrochemical carbonization of PTFE on a Pt electrode in aprotic electrolyte solution is also possible [3], but the amalgam-driven process is superior, presenting a clean and well-defined alternative to classical (wet) electrochemistry. 

Fluoropolymers are still one of the largest scale applications of fluororganic compounds [1]. This field began with the serendipitous discovery of poly(tetrafluoro-ethylene) (PTFE, or Teflon) by R. J. Plunkett at DuPont in 1938 (Figure 4.1). When... 

Poly-tetrafluoro-ethylene film Polyethylene (low 328 350 Unknown... 

Expanded poly(tetrafluoro ethylene) (ePTFE) CORE-TEX W.L. Core Associates, Flagstaff, USA Regenerative membrane, osteoconductive membrane, large diameter aortic, and carotid vascular grafts, tension-free repair of ventral incisional hernia orbital reconstruction, facial reconstruction, rhinoplasty... 

TUM Tuminello, W.H., Brill, D.J., Walsh, D.J., and Paulaitis, M E., Dissolving poly(tetrafluoro-ethylene) in low boiling halocaibons, J. Appl Polym. Sci., 56, 495, 1995. 

This is a thermoplastic material, the correct name for which is poly-tetrafluoro-ethylene, though it is usually referred to as PTFE. 

The discussed examples of random rotational and translation displacement disorder of chains around their axes have important implications for the interpretation of the X-ray fiber diffraction patterns of poly(tetrafluoro-ethylene) oriented samples in the mesomorphic forms stable at high temperatures (Sect. 5.7). 

Scratchproof coatings on poly(methyl methacrylate) can be produced by application of a 50 50 mixture of poly(silicic acid) and poly(tetrafluoro-ethylene-co-hydroxyalkyl vinyl ether). It is not known why coatings as scratchproof as glass can be produced in this manner. 

Poly(tetrafluoro ethylene) and Poly(fluoioe1hylene/pirqrylene Ct lymer), J. Appl. Polym. ScL, 25, 1755 (1980). 

The composition and curing properties of epoxy resins are of great commercial importance, and many workers have published separations. Heitz [38] used a poly(vinylacetate) gel with a coiled poly(tetrafluoro ethylene) column (1000 x 0.2 cm), with dimethylformamide as eluent at a very low flow rate. This gave plate counts of up to 160000. He showed the separation of oligomers up to n = 10, but other smaller components, which have different end groups, are visible. The telomerization of tetrahydrofuran is also described. 

In fluorinated polyalkanes, the C—F bond is very resistant to thermal or chemical scission because of both the high bond energy of the carbon-fluorine bond (Table 25-5) and the associated decrease in the C—F bond length. The most striking representative of this group is poly(tetrafluoro-ethylene), - CF2—CF2-)- , which was first introduced commercially as Teflon by Du Pont. However, the name Teflon has now become a generic name for a whole series of fluorinated polyalkanes. 

Baradie, B., et al.. Synthesis and solubility of linear poly(tetrafluoro-ethylene-co-vinyl acetate) in dense C02 Experimental and molecular modeling results. Macromolecules, 2004. 37(20) p. 7799-7807. 

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