Properties and structure of (50 ? x)BaO–xZnO–50P2O5 glasses

The thermal, mechanical, chemical properties and the structure of (50 ? x)BaO–xZnO–50P₂O₅ (0 ? x ? 50 mol%) glasses were investigated. For these glasses, the density (ρ), glass transition temperature (T_g), dissolution rate (DR), ³¹P magic angle spinning nuclear magnetic resonance (MAS-NMR) spectra and Fourier-transformed infrared (FTIR) spectra were determined. As BaO was replaced by ZnO, all the properties were similarly decreased in density, Young’s modulus, T_g and water resistance. FTIR analyses revealed a shortening of phosphate chains by the shift of (P–O–P)_as band to a higher wave number owing to the substitution ZnO of BaO. The NMR spectra showed that the replacement of BaO by ZnO decreased the concentration of Q²-tetrahedral sites and increased that of Q¹-tetrahedral sites.