Temperature-dependent mechanisms of the atmospheric alteration of a mixed-alkali lime silicate glass

Abstract : The atmospheric alteration of a mixed-alkali lime silicate glass is described as a function of time and temperature. The glass hydration kinetics self-accelerates with time and is considerably enhanced with the temperature. At 80 °C, alkali and alkaline earth ions are retained in hydrate-type environments while at 40 °C, they are partially leached out forming surface carbonates, in the order Ca2+>Na+>>K+. The temperature dependency of hydrolysis processes, the important role of the hydration energy of cations and the diminished solvation properties of bound water are considered to discuss experimental observations and advance in the understanding of the specificities of glass atmospheric alteration.