The structural changes of the amorphous silicate network in the oxyfluoride aluminosilicate glass series was investigated as a function of SrO for CaO substitution (0.0 to 2.0 moles). Using Fourier Transform Infrared (FTIR) spectroscopy coupled with Gaussian deconvolution, this study quantifies the transition from a polymerised calcium-aluminosilicate framework to a more fragmented strontium-calcium aluminosilicate architecture. Results demonstrate a linear increase in Q 3 species and a concomitant rise in structural disorder (FWHM) and bond strengths around the silicate tetrahedra. These findings confirm that Sr 2+ acts as a much more potent network modifier than previously thought, inducing direct network depolymerisation that likely dictates the energy kinetics and thermodynamics for the subsequent crystalline phase formation.
Tomas Duminis (Wed,) studied this question.