Makoto HADA
Measurements of dynamic viscoelasticity of oxide glasses
Kazumasa MATUSITA
It has been desired to analyze viscoelasticity of glasses quantitatively far below Tg. There are static and dynamic methods in the viscoelasticity measurement. In the latter, elastic and viscous components can be measured simultaneously in short time.
In this study, dynamic method was established for the viscoelasticity measurements of oxide glasses. Furthermore, was investigated the relationship between viscosity and volume based on free volume theory.
As a result, it was found that the viscosity (log(/(PaEs))) at Tg of phosphate and borate glasses measured by dynamic method was about 12 and agreed with that by static method. It was also found that as the temperature is decreasing to 50, the viscosity increases close to 15|16. It was confirmed that the variation of viscosity from room temperature to near Tg could be expressed by free volume theory.