Bioactive Organic-Inorganic Hybrids Based on CaO - SiO_2 Sol-Gel Glasses

摘要

Bioactive organic-inorganic hybrids, CaO-SiO_2-poly(dimethylsiloxane) (PDMS) and CaO-SiO_2-poly(vinyl alcohol) (PVA), were synthesized by a sol-gel method and characterized before and after soaking in Kokubo's Simulated Body Fluid (SBF). The synthesis conditions to obtain monoliths were established in both series. CaO-SiO_2-PDMS hybrids presented elastic behavior when TEOS∶PDMS molar ratio was under 3.5, and they showed in vitro bioactivity when Ca(NO_3)_2.4H_2O∶TEOS molar ratio was close to 0.10. Moreover, the relative amount of H_2O used for TEOS hydrolysis also played a role in their mechanical behavior and in vitro bioactivity. In the CaO-SiO_2-PVA hybrids, the presence of PVA favored both the synthesis of crack-free monoliths as well as a marked degradation, around to 50 wt-%, for the first 6 h in SBF. All the studied compositions presented in vitro bioactivity. In addition, PVA contents played a major role in the in vitro behavior.