Preparation and properties of SnO–SnCl2–P2O5 glass

Abstract The glass forming region in the ternary system SnO–SnCl 2 –P 2 O 5 has been determined. Glass transition temperature ( T g ), dilatomeric softening temperature ( T s ) of the glass, and the viscosity of the liquids in the binary SnO–P 2 O 5 and SnCl 2 –P 2 O 5 systems were measured. Compositional dependencies of these properties have been investigated. The T g and T s of the glasses and the viscosity of liquids for the SnO–P 2 O 5 glasses increase linearly with increasing SnO content in a range of 40–60 mol% SnO. The substitution of chlorine for oxygen by increasing the SnCl 2 /SnO ratio results in a decrease of T g and T s of the glasses and the viscosity of the liquids. The T g and T s of the glasses and the viscosity of the liquids of the SnCl 2 –P 2 O 5 system increase between 40 and 60 mol% SnCl 2 , are a maximum at about 60 mol% SnCl 2 , and then decrease with further addition. The SnCl 2 –P 2 O 5 systems had a decreasing viscosity, which is not observed in the SnO–P 2 O 5 and SnF 2 –P 2 O 5 systems. The 70SnCl 2 –30P 2 O 5 glass, having a viscosity between 0.4 and 10 Pa s in a temperature range of 500–600 K, would be useful in a practical application for sealing glasses.