Published online by Cambridge University Press: 21 February 2011
Solutions have been prepared containing silicon ethoxide, titanium butoxide, and zirconium propoxide as metal organic compounds. Additions of water (for hydrolysis), solvents (ethanol, formamide), and hydrochloric acid (as a catalyst) have been varied systematically. The reaction kinetics of the hydrolysis and condensation steps in these mixtures have been studied by measuring viscosity and 29Si NMR data as a function of time. After gelling, the products have been dried and then converted to glassy materials by firing. Temperatures well below 1000 °C have been used for that. Glasses from the title system have been obtained both in bulk and in thin film form. Properties like density, specific surface, and hardness have been investigated and are reported as well.