Investigation of physical, mechanical and in-vitro bioactivity of bioactive glass-ceramics fabricated from waste soda-lime-silica glass doped P2O5 by microwave irradiation sintering

Abstract

The ever-increasing generation of waste glass, poses a major environmental challenges due to its large volume and limited recycling options. This research explores a novel sustainable approach to repurposing this waste by transforming it into silicate based bioactive glass-ceramics (SBGCs). The glass waste was recycled into powder form and homogeneously mixed with sodium dihydrogen orthophosphate (NaH 2 PO 4 ) in the step of 2, 4, 6, 8 and 10 wt % respectively with addition of organic binder and sintered by microwave irradiation approach. The obtained SBGCs were then characterized for its phase constituents, microstructure, physical, mechanical, and in-vitro bioactivity behaviour. The results showed that the samples exhibited considerable density and porosity while both the micro-hardness and compressive strength decreased with increased phosphate content. Sample SLP2% showed optimum hardness and compressive strength of 7.3 GPa and 87 MPa respectively. Combeite was obtained as the major phase while wollastonite and quartz were also detected. The developed SBGCs also showed increased hydroxyapatite (HA) formation after immersion in simulated body fluid (SBF) and displayed good antibacterial capacity when reacted with four bacteria strains. The results obtained indicate that the developed SBGCs might be considered a potential candidate for biomedical applications. However, sample SLP8% is the best sample to serve as bioactive glass-ceramics considering the combination of its high HA and good CHA formation, besides its considerable density and mechanical properties.