Structural and Physical Properties of Iron Oxychloride Phosphate Glasses

Glasses in the system xFeCl₃–10Fe₂O₃–(90–x)P₂O₅ have been prepared by the normal quenching method over a wide range of composition (x = 15 up to 50 mol%). The glass structure has been investigated using IR spectral analyses which shows that the intermediate range order is affected by substitution of FeCl₃ for P₂O₅. Thermal expansion coefficient, glass transition temperature, density and dissolution rate in HCl were also investigated. The formation of P–O–Fe and P–Cl bonds at the expense of P = O bonds is responsible for the good chemical durability of the studied glasses. Changes in other properties are interpreted in terms of the depolymerization of the glassy matrix by FeCl₃.