Phosphate based glass

PIA-Calcium Phosphate-Based Glass Fibers Artificial Tendon and Ligament... 

A number of other phosphate-based glass-ceramic systems have been investigated. Fine-grained glass-ceramics based on crystals isostructural with NZP (NaZt O ) can be prepared from certain transition-metal orthophosphate and silicophosphate glasses (27). The extensive solid solution possible in the NZP phase provides for a wide range in thermal expansion, with coefficients ranging from —20 to 60 x 10-7 /°C. 

Knowles, J.C. Phosphate based glasses for biomedical applications. J. Mater. Chem. 2003, 13, 2395-2401. 

Alumino-phosphate-based glasses were extensively studied to understand their excellent resistance against water attack [43]. In 2000, Egan used the CP technique on sodium alumino-phosphate to edit 2D correlation maps tracing the nature of the P—O—A1 bonds by differencing, along... 

The D-HMQC technique also participates to the reinvestigation of boro-phosphate-based glasses structure in 2011 [48,49]. These glasses, investigated for their high thermal stabiHty and for their ionic conductivity when alkali ions are inserted in the formulation, have been studied by CP-MAS in 2005 [50]. The first ever reported 2D correlation map clearly shows... 

Immobilization is carried out with a phosphate based glass and an assumed waste loading of 15 wt.%, reaching a density of 2.85 kg/dm. ... 

Metaphosphate glasses are of particular interest in the development of glass-ceramics and glass-ceramic fibers (Griffith 1995) by the controlled crystallization of phosphate base glasses. These glasses are composed of (PO ) tetrahedra chains. In chemical terms, these structural units must be called condensed phosphates. 

BPO glass-ceramics are also characterized by a low dielectric constant between 3.8 and 4.5. As a result, the material is suitable for microelectronic applications, where circuit speed is inversely related to the square root of the dielectric constant. Since phosphate-based glass-ceramics are known to exhibit a coefficient of thermal expansion exceeding 100 x 10 K , this coefficient had to be lowered before the material could be used for microelectronic packaging of silicon circuitry. This objective was fulfilled using Si02-rich glass-ceramics, for example, with composition 1 in Table 2-24. A coefficient of thermal expansion of almost 40 x 10" (20°C-300°C) was... 

A. ffiani, L.S. CahiU, E.A. Abou Neel, J.V. Hanna, M.E. Smith, J.C. Knowles, Physical properties and MAS-NMR studies of titanium phosphate-based glasses. Mater. Chem. Phys. 120(1), 68-74 (2010)... 

In general the Ni-YSZ cermet is very stable towards other stack components. No detrimental reactions are detected for silica-based glass seals in contact with the cermet, whereas Ni-depletion by nickel-phosphate formation is observed by reaction with phosphate-based glasses [44]. 

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