Predicting the dissolution rate of borosilicate glasses using QSPR analysis based on molecular dynamics simulations

Quantitative Structure Property Relationship (QSPR) analysis based on molecular dynamics (MD) simulations is a promising approach for establishing the composition-property relationships of glasses and other materials with complex structures. A series of 20 borosilicate, aluminosilicate, and boroaluminosilicate glasses have been modeled using MD simulations with recently developed effective potentials. Short- and medium-range structures of these glasses were analyzed and, based on the structural information, QSPR analysis of the initial dissolution rates (r₀) of these glasses that were measured at 90°C and pH 9 by using various structural descriptors such as percentage of bridging oxygen species, network connectivity, and average ring size. The structural descriptor, F_net, which contains both energetic information such as single bond strength and structural information such as cation coordination number and Q_n distribution, was also used. It was found that while the overall network connectivity, average ring size and F_net provide reasonable correlations with r₀ of studied glasses, F_net gives the best correlation among the descriptors. For glasses that show incongruent dissolution, it was found that modification of glass compositions to account for preferential release of modifier cations is necessary to achieve best correlations. The findings were discussed with results of recent studies on evaluating the compositional dependence of glass dissolution behavior using the topological-constraints-based models.