Aluminosilicate glasses types

In 1968 Wilson published an account of his early search for alternatives to orthophosphoric acid as a cement-former with aluminosilicate glasses. Aluminosilicate glasses of the type used in dental silicate cements were used in the study and were reacted with concentrated solutions of various organic and inorganic adds. Wilson (1968) made certain general observations on the nature of cement formation which apply to all cements based on aluminosilicate glasses. 

Ellis and Wilson also examined cement formation from aluminosilicate glasses and concentrated solutions of PVPA (Wilson Ellis, 1989 Ellis, 1989 Ellis Wilson, 1990). These cements, like the glass polyalkenoate cements, are a type of glass-ionomer cement. 

In principle these compounds offer access to materials with AliCh-SiCL and Al203 2Si02 stoichiometries. The latter stoichiometry is equivalent to the Al[OSi(OBu-t)3 (OBu-t)] precursor. The major drawbacks with these materials are their air and moisture sensitivity, and the cost of the starting materials. Although the idealized stoichiometries of the above ceramics products are not those of crystalline aluminosilicates, amorphous aluminosilicate glasses are often important in optical applications or in scratch-resistant coatings. Furthermore, they may offer potential for CVD-type applications. There still remains considerable need for simple precursors to crystalline aluminosilicates, especially for structural applications. Dense, phase pure crystalline ceramic materials are desired for optimal mechanical properties, e.g. ceramic fibers for composite manufacture. 

Type /, Class B glass is an aluminosilicate glass. It can be used for all... 

Alkaline earth feldspar glass with excess Si02 (Types E and F). Thirty to fifty wt% of an aluminosilicate glass matrix of the 7 0 Al203 wSi02 type where R = Ca, Ba, Sr and n = 2 can be incorporated for alkaline earth feldspars. 

The T. of alkaline earth aluminosilicate glasses of the type used for halogen headlamp inner bulb application may be estimated by the relation ... 

Calorimetric data on sodium and calcium aluminosilicate crystals and glasses (Navrotsky et al., 1982, 1985) indicate that, in an exchange reaction of type... 

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