Fluoride glasses reviewed

TaF has been characterized by ir, Raman, x-ray diffraction, and mass spectrometry (3,11,12). TaF has been used as a superacid catalyst for the conversion of CH to gasoline-range hydrocarbons (qv) (12) in the manufacture of fluoride glass and fluoride glass optical fiber preforms (13), and incorporated in semiconductor devices (14). TaF is also a catalyst for the Hquid-phase addition of HF to polychlorinated ethenes (15). The chemistry of TaF has been reviewed (1,16—19). Total commercial production for TaF is thought to be no more than a few hundred kilograms aimuaHy. 

This paper reviews the optical properties of undoped and activated fluoride glasses for the period 1985-1998. First, the infrared transmission, Rayleigh scattering, and refractive indices of several fluoride glasses are given and discussed. For the sake of completeness, fundamental physical characteristics such as thermo-mechanical properties are also given, although they may have been published before this period. 

Gan, F., 1995. Optical properties of fluoride glasses a review. J. Non-Cryst. Solids 184, 9 20. 

Takahashi, S., 1992. Prospects for ultra-low loss using fluoride glass optical fiber a review. J. Non-Ciyst. Solids 140, 172-178. 

Tran, D., Sigel, G., Bendow, B., 1984. Heavy metal fluoride glasses and fibers a review. J. Lightw. Technol. 2 (5), 566—586. 

Gamard A., Babot O., Jousseaume B., Rascle M.C., Toupance T., Campet G. Conductive F-doped tin dioxide sol-gel materials from fluorinated beta-diketonate tin(IV) complexes. Characterization and thermolytic behavior. Chem. Mater. 2000 12 3419-3426 Gan F.X. Optical-properties of fluoride glasses—a review. J. Non-Cryst. Solids 1995 184 9-20... 

Moisture Deteriorating effects of moisture are well known as reviewed early in this chapter (OTHER BEHAVIOR, Drying Plastic). Examples for high moisture applications include polyphenylene oxide, polysulfone, acrylic, butyrate, diallyl phthalate, glass-bonded mica, mineral-filled phenolic, chlorotrifluoroethylene, vinylidene, chlorinated polyether chloride, vinylidene fluoride, and fluorocarbon. Diallyl phthalate, polysulfone, and polyphenylene oxide have performed well with moisture/steam on one side and air on the other (a troublesome... 

Safety glasses must be worn in the laboratory at all times. Other personal protection equipment should be worn as needed, especially appropriate safety gloves. Sodium fluoride is a deadly poison if ingested full chemical precautions should be observed. Material safety data sheets (MSDS) should be reviewed before beginning the experiment. 

Mixtures of poly(vinylidene fluoride) with poly (methyl methacrylate) and with poly (ethyl methacrylate) form compatible blends. As evidence of compatibility, single glass transition temperatures are observed for the mixtures, and transparency is observed over a broad range of composition. These criteria, in combination, are acceptable evidence for true molecular intermixing (1, 19). These systems are particularly interesting in view of Bohns (1) review, in which he concludes that a compatible mixture of one crystalline polymer with any other polymer is unlikely except in the remotely possible case of mixed crystal formation. In the present case, the crystalline PVdF is effectively dissolved into the amorphous methacrylate polymer melt, and the dissolved, now amorphous, PVdF behaves as a plasticizer for the glassy methacrylate polymers. 

Within a few years these very first results were followed by laser effects in other R ions such as Pr +, Ho +, Er +, Tm +, Yb +, Dy +. In particular Er laser emission at 1.5 pm was obtained in silica glass (Snitzer and Woodcock 1965), and studied in phosphate, beryllium fluoride, fluorophosphate glasses (Auzel 1966a, 1968). All these pioneer results have already been reviewed in several books (for instance, Di Bartolo 1968, Roess 1969, Weber 1979 in volume 4 of this Handbook Kaminskii 1981, Reisfeld and Jorgensen 1977). 

Hydrogen fluoride is a powerful solvent but its use has been severly restricted both by its reactivity towards glass and silica and by its physiological properties. Experimental techniques have, however, been developed which allow the more widespread use of this interesting solvent. Polytetrafluoroethylene and poly-chlorotrifluoroethylene (the latter being transparent) are now available to handle liquid hydrogen fluoride. Some details have been given in a recent review article. ... 

Except for the trifluoride, anhydrous californium trihalides are hygroscopic and must be protected from moisture. The dihalides are very sensitive to both moisture and oxygen. Normally, their syntheses are carried out in glass (except for fluorides) so that products can be flame-sealed in situ, avoiding subsequent transfers of the products. Some preparative and experimental techniques for studying californium halides have been reviewed [74,146]. 

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