Tetrafluoroethylene fibers

The electrochemical oxidation of phenols produces quinones that can be used as dienophiles for the Diels-Alder reaction. A typical example is shown in Scheme 14, where a lithium perchlorate/nitromethane system and an electrode coated with a PTFE [poly-(tetrafluoroethylene)] fiber, to create a hydrophobic reaction layer. 

Z.H. Wang, Z.P. Zhang, Z.P. Wang, L.W. Liu, X.P. Yan, Acrylic acid grafted poly-tetrafluoroethylene fiber as new packing for flow injection on-line microcolumn preconcentration coupled with flame atomic absorption spectrometry for determination of lead and cadmium in environmental and biological samples, Anal. Chim. Acta 514 (2004) 151. 

Poly(phenylene sulfone) see also PPSU Poly(tetrafluoroethylene) fibers... 

Shaw, D. and Shoichet, M.S., Toward spinal cord injury repair strategies peptide surface modification of expanded poly(tetrafluoroethylene) fibers for guided neurite outgrowth in vitro, J. Craniofac. Surg. 14,308,2003. 

Fluorinated ethylene-propylene resin Poly(vinylidene fluoride) Ethylene-tetrafluoroethylene copolymer Ethylene- chlorotrifluoro- ethylene copolymer Cellulose- filled Glass-fiber- reinforced... 

Liquid polyalurninum chloride is acidic and corrosive to common metals. Suitable materials for constmction of storage and handling facilities include synthetic mbber-lined steel, corrosion resistant fiber glass reinforced plastics (FRP), ceramics, tetrafluoroethylene polymer (PTFE), poly(vinyhdene fluoride) (PVDF), polyethylene, polypropylene, and poly(vinyl chloride) (PVG). Suitable shipping containers include mbber-lined tank tmcks and rail cars for bulk shipment and plastic-lined or aH-plastic dmms and tote bins for smaller quantities. Except for aluminum chlorohydrates, PAG products are shipped as hazardous substances because of their acidity. 

Thermal properties. See also Temperature of aromatic polyamides, 19 718 of asbestos, 3 300-304 of diesel fuel, 12 423 of ethylene—tetrafluoroethylene copolymers, 18 319-321 of fibers, 11 167 of filled polymers, 11 309—310 of gallium, 12 342 of glass, 12 588... 

Wallace Carothers and coworkers at DuPont synthesized aliphatic polyesters in the 1930s [Furukawa, 1998 Hounshell and Smith, 1988]. These had melting points below 100°C, which made them unsuitable for firber use. Carothers then turned successfully to polyamides, based on the theoretical consideration that amides melt higher than esters. Polyamides were the first synthetic fibers to be produced commercially. The polyester and polyamide research at DuPont had a major impact on all of polymer science. Carothers laid the foundation for much of our understanding of how to synthesize polymeric materials. Out of that work came other discoveries in the late 1930s, including neoprene, an elastomer produced from chloro-prene, and Teflon, produced from tetrafluoroethylene. The initial commercial application for nylon 6/6 was women s hosiery, but this was short-lived with the intrusion of World War II. The entire nylon 6/6 production was allocated to the war effort in applications for parachutes, tire cord, sewing thread, and rope. The civilian applications for nylon products burst forth and expanded rapidly after the war. 

In order to fabricate a resin laminated copper foil, the composition is poured over a glass cloth placed on a glass fiber reinforced poly-(tetrafluoroethylene) (PTFE) film. Another sheet PTFE film is placed... 

Studies of the plasma polymerization of tetrafluoroethylene in such a capacltively coupled system are described in another paper presented at this symposium [ 9]. The apparatus has been used to coat polysulfone hollow fibers with pyridine and acetylene + nitrogen plasma polymer to form a composite reverse osmosis desalination membrane. Salt rejections of 90-93% have been achieved at fluxes of 1.5-2.0 g.f.d with a fiber take up rate of 50-100 cm/min. 

This is analogous to the extraction of sugars with boronic acids described earlier. The recovery of phenylalanine from a fermentation broth has been simplified by using a microporous poly(tetrafluoroethylene) membrane with tri-/j-octylmethylammonium chloride in toluene in the pores.133 Phenylalanine can also be separated using the quaternary ammonium salt with 2-nitrophenyl octyl ether in a cellulose triacetate membrane.134 Kerosene flowing in hollow fiber membranes can remove 99.9% of organic pollutants, such as benzene, p dichlorobenzenc, chloroform, and carbon tetrachloride, from wastewater outside the fibers.135... 

Through plasma treatment, grafing of monomers can also take place on the polymer surface. For example, monomers, e.g., tetrafluoroethylene or hexafluoroethane, can be grafted onto wool or polypropylene fibers ( ). This type of grafting can improve such tribological properties as low friction. 

Other examples of well-established trade names are Kevlar (poly(paraphenylene terephthalamide)), Plexy-glass (sheets of poly(methyl methacrylate)). Teflon (poly(tetrafluoroethylene)), and Dacron (PET fiber). 

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