EFFECT OF WATER CONTENT ON PROPERTIES OF Na 2 0 . 3 Si 0 2 GLASSES

Na20-3Si02 glasses with up to =12 wtZ water were prepared under high-pressure, hydrothermal conditions and their densities, glass transition temperatures, mechanical properties, electrical conductivities, sodium diffusion coefficients and radiation effects were measured. The density, glass transition temperature, hardness and brittleness decreased with increasing water content. The conductivity was found to depend on H2VO content in a manner similar to the "mixed-alkali" effect. Glasses with high water content were found to be extremely resistant to radiation coloration.