Densification-crystallization behavior of biodegradable copper-doped modified 45S5 glasses

In the current work, modified 45S5 glasses containing different amounts of copper oxide (1, 3, and 5 weight ratios) were prepared using melting procedure and characterized for their physical properties after sintering at various temperatures. Characterization of the copper doped glasses was performed using various analytical techniques, including X-ray diffractometry, differential thermal analysis, and scanning electron microscopy. To this purpose, a systematic study was conducted on densification-crystallization of the copper doped glasses and optimizing sintering temperature. Differential thermal analysis revealed weak exothermic peaks located above 800 °C, corresponding to the crystallization temperature (Tc) of the studied glasses. This analysis suggests that copper oxide has a limited effect on the thermal properties of the modified 45S5 glasses. Densification behavior of glass specimens was studied at temperatures ranging from 600 to 850 °C. The optimal densification temperature was found to be 650 °C, respectively. The results indicated that the presence of copper ions in the structure of studied glasses results in the formation of porous structures after sintering. It seems that copper ions generate oxygen gas during sintering and promote the formation of a cellular foam structures.