| Abstrakt: |
A series of transparent SnO-P2O5 (SP) and SnO-P2O5-B2O3 (SPB) glasses, with the composition 67SnO-(33-x) P2O5-XB2O3 where X=0, 3, 5, 7 and 10 mol%, were immersed in distilled water at 40 and 70°C for up to 504 hours (3 weeks). Their dissolution behaviour was evaluated by macroscopic inspection, by measurement of weight loss per unit area, changes in the pH of the solution, x-ray diffraction analysis and infrared spectroscopy. The dissolution of Q1 phosphate species and/or BO3 and BO4 borate units into water for the SP and SPB glasses with ⩽7 mol% B2O3 is accompanies crystallization of Sn3(PO4)2. Infrared spectroscopy provides further evidence of the good durability of SPB glass containing 10 mol% B2O3 and reveals the formation of a hydrous layer related to B-O-B linkages on the glass surface. [ABSTRACT FROM AUTHOR] |
