Netsu Sokutei, 50 (2), p. 63, (2023)



Glass Transition on Viscosity Measurements

The glass transition has been observed using apparatuses for viscosity and calorimetry measurements. We developed a new method which can measure a high viscosity of an equilibrated glass using the same specimen in a whole temperature range near the glass transition temperature (Tg). The glass transition was discussed using obtained data based on the Adam-Gibbs theory. We propose a new model of intermediate-range orders (IROs) such as cooperatively rearranging regions (CRRs). After IROs emerge at the mode coupling temperature (Tc) due to a cage effect in a supercooled liquid, IROs freeze at Tg to make a glass state. A glass relaxes to an ideal glass during prolonged aging due to the enthalpy recovery below the Kauzmann temperature (TK). An ideal glass reaches to a polycrystal during an extremely long time due to the structural recovery. An ideal glass has the dissipative structure in a nonequilibrium steady state, which was presented by Prigogine.