The role of MgO on the structural properties of CaO–Na2O(MgO)–P2O5–CaF2–SiO2 derived glass ceramics

Bioactive Glasses with Low Ca/P Ratio and Enhanced Bioactivity

“…To discuss this behavior, another subject has to be brought into account, which is the increase in the Ca/P ratio of the glass as CaF 2 increases. It is already known that fluorapatite undergoes phase separation below crystallization [35]. Thus, glasses with higher amount of P 2 O 5 (as glass B4) would present a lower activation energy for the nucleation of fluorapatite, as the addition of P 2 O 5 induces phase separation in the glass network.…”

“…Furthermore, it was already studied that, apart from being a network modifier, MgO may be also considered as an intermediate oxide that is stored in the network in the form of MgO 4 . The intercalation of this MgO 4 species in the glass network contributes to an increase in the polymerization of the glass, which in turn results in a decrease of bioactivity [35]. …”

“…The presence of MgO in the glass B32 caused a slightly lower solubility of the same until seven days of immersion in SBF solution. This lower glass degradability may arise not only from the higher energy of Mg–O bond, limiting its reactivity and ion leaching, but also from the role of this oxide in glass network, that may to act either as a glass modifier or as an intermediate oxide [35,51]. After 14 days immersion in SBF solution, this glass presents a slightly higher solubility that may be linked with an increased kinetics of ionic exchange between the glass and SBF solution at this stage, which is in accordance with the pH changes observed for this same time period (Figure 9).…”

Self‐Healing Behavior of Barium–Lanthanum–Borosilicate Glass and Its Reactivity with Different Electrolytes for SOFC Applications

“…After 750‐h treatment, BL glass gets converted to glass ceramic as BaSiO 3 phase has been obtained for both the coupled glasses. These glass ceramics are basically polycrystalline solids with residual glassy matrix, which leads to their characteristic microstructure allowing better performance . Moreover, higher temperature and longer time is required for BL glass indicating its high devitrification resistance.…”

“…These glass ceramics are basically polycrystalline solids with residual glassy matrix, which leads to their characteristic microstructure allowing better performance. 54 Moreover, higher temperature and longer time is required for BL glass indicating its high devitrification resistance. La 2 O 3 is considered to be an oxide, which is used to reduce the tendency of glass melt to devitrify.…”