Chemical durability of glasses; a thermodynamic approach

The various hypotheses regarding corrosion of oxide glass surface by aqueous solutions have been reviewed. It has been shown that the long-term chemical resistance of a glass is mainly determined by the thermodynamic activity and stability of its component oxides in aqueous solutions. The stability of different oxides commonly used in glass-making like SiO2, ZnO, PbO, Al2O3, ZrO2 etc. in aqueous solutions of different pH has been calculated with available thermodynamic data, and these have been discussed in relation to the corrosion behaviour of glasses (prepared with these oxides) in aqueous solutions of various pH range. Suitable experimental results have been furnished to justify the importance of thermodynamic stability of component oxides of a glass on its corrosion behaviour in aqueous solutions.