Examining correlations between the dissolution rates and optical basicity of modified aluminoborate glasses

Abstract

Methods for determining the dissolution rate of glass networks vary based on the application, glass chemistry, and morphology. Research spanning many glass systems has resulted in a substantial amount of dissolution data, but inconsistencies limit the utility of the data collected. Furthermore, predicting the dissolution of any glass system remains a critical challenge for many industrial glass applications. This work compares the dissolution of five single modified (Na, K, Ca, Sr, and Ba) aluminoborate glasses to their optical basicity values to gain fundamental understanding of how the glass composition influences dissolution at 37°C in alkaline water. X-ray photoelectron spectroscopy (XPS) was used to directly measure the binding energy of the oxygen in each glass to evaluate the underlying glass structure. Results showed that aluminoborate glasses synthesized with monovalent cations exhibit approximately an order of magnitude faster dissolution of the modifier ion compared to divalent cation glasses. Further grouping in the monovalent and divalent glasses is observed in the normalized dissolution rate of B and Al from the glass network. No correlation was observed between the normalized forward dissolution rate of boron, the primary network former, and the measured binding energy of the aluminoborate glasses. Furthermore, no defined trend was observed between the optical basicity and O1s binding energy in the modified aluminoborate glass compositions.