Abstract:
Batches of 48SiO2 – 6CaO – 8SrO – 36ZnO – 2P2O5 (mol%) ‘control’ glass and a similar ‘GE-2’ glass with 12 mol% GeO2, in lieu SiO2, were produced. These glass powders were then annealed and mixed with E9 or E11 polyacrylic acid (PAA) and water in order to form Ge-GPC (glass polyalkenoate cement) samples for compression testing. Two types of synthetic media were employed for this study, simulated body fluid (SBF) and simulated gastric fluid (SGF). Each Ge-GPC was submerged in ~5 ml of the corresponding media (SBF and SGF) and allowed remained submerged for a specific period of time (1, 10, 100, 1000 hours) in groups of 5. After soaking in the media for the allotted time, the samples in each group were then tested in compression using an Instron 5566 testing machine. The samples’ apparent stiffness, compressive strengths, and moduli of compression were calculated. The resulting data suggested that the GE-2 GPCs become stronger over time when exposed to the SBF media. The differences at each time period border between being statistically significant and statistically insignificant but are noticeable nonetheless. Lastly, it is already known that in general, higher MW acids (E11), create GPC’s with slightly stronger mechanical properties than lower MW acids (E9). This trend appears to hold true for the Ge GPC’s as part of this work, but the data also indicates that the acid MW could positively impact the Ge-GPC’s ability to strengthen over time in the media.
