Silicate glass properties

The physical and chemical properties of silicate glasses depend on the composition of the material, ion size, and cation coordination number (9). A melt or glass having a Si02/Na20 ratio of 1, ie, sodium metasiUcate [1344-09-8] is expected to possess a high proportion of (SiO ) chains. At a ratio of 2, sheets might predominate. However, litde direct evidence has been shown for a clear predominance of any of these stmctures. The potential stmctures of sihcate melts of different ratios are discussed in detail elsewhere (10—12). 

Silicon shows a rich variety of chemical properties and it lies at the heart of much modern technology/ Indeed, it ranges from such bulk commodities as concrete, clays and ceramics, through more chemically modified systems such as soluble silicates, glasses and glazes to the recent industries based on silicone polymers and solid-state electronics devices. The refined technology of ultrapure silicon itself is perhaps the most elegant example of the close relation between chemistry and solid-state physics and has led to numerous developments such as the transistor, printed circuits and microelectronics (p. 332). 

Physical properties, silicate glasses. 152-54 Phytoplankton, impact of Pu waste. 275-92... 

Silicate glasses, physical properties, 150-54 Single-phase reactions, ground-water 335-44 Site, ground-water leaching,... 

Orthopedic devices, 3 721-735 joint replacement, 3 727-735 Orthopedic marrow needles, 3 743-744 Orthophosphate (PO4), in soil, 11 112 Orthophosphates, 18 830-841 20 637 magnesium, 18 839 manufacture of, 18 853-855 Orthophosphate salts, 18 836 Orthophosphoric acid, 18 815, 817-826 condensation of, 18 826 properties of, 18 817-819 solubility of boron halides in, 4 140t orf/zo-phthalic resins, 20 101, 113 formulation of, 20 102 Orthorhombic crystal system, 8 114t Orthorhombic phosphorus pentoxide, 19 49 Orthorhombic structure, of ferroelectric crystals, 11 95, 96 Orthorhombic symmetry, 8 114t Orthosilicate monomers, in silicate glasses, 22 453... 

Silicate glasses, 72 571-572, 608 durability of, 72 584-585 modulus of elasticity of, 72 590 thermal properties of, 72 588 Silicate glasses, atomic structure of, 22 453-454... 

Richet P. and Bottinga Y. (1986). Thermochemical properties of silicate glasses and liquids A review. Rev. Geophys. Space Phys., 24 1-25. 

Brezhneva, N. E., Oziraner, S. G., Minaev, A. A. Kuztetsov, D. G. 1976. Properties of phosphate and silicate glasses for solidification of radioactive wastes. In Management of Radioactive Wastes from the Nuclear Fuel Cycle. IAEA, Vienna, 2, 85-94. 

Glass fibers are the most common reinforcing fiber due to their excellent combination of mechanical properties, dielectric properties, thermal stability and relatively low cost. As a result, there are many different types of silicate glass fibers, all with varying properties designed for various applications (see Table 1.32). The majority... 

Chemical Properties. The chemical durability is a function of the durability of the crystals and the residual glass. Generally, highly siliceous glass-ceramics with low alkali residual glasses, such as glass-ceramics based on quartz and (3-spodumene, have excellent chemical durability and corrosion resistance similar to that obtained in borosilicate glasses. 

Botkin P. Ya., 1970, Mekhanicheskie svoistva silikatnykh stekol (Mechanical Properties of Silicate Glasses), Izd. Nauka, Leningrad. 

The most important property of sodium and potassium silicate glasses and hydrated amorphous powders is their solubility in water. The dissolution of vitreous alkali is a two-stage process. In an ion-exchange process between the alkali-metal ions in the glass and the hydrogen ions in the aqueous phase, the aqueous phase becomes alkaline, due to the excess of hydroxyl ions produced while a protective layer of silanol groups is formed in the surface of the glass. In the second phase, a nucleophilic depolymerization similar to the base-catalyzed depolymerization of silicate micelles in water takes place. 

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