Phosphate-rich glass powders in the CaO-P2O5 system were prepared by the sol-gel method using aqueous solutions of Ca(NO3)2·4H2O and H3PO4. Glass powders were subjected to reaction with Ca(OH)2 and water under varied experimental conditions, such as temperature (25-90 °C), particle size (1-5 and 40 μm), and ultrasound waves (20 kHz). Parallel experiments were also conducted without ultrasound for comparison. The reaction products were composed of Ca(H2PO4)2·H2O (monocalcium phosphate monohydrate), CaHPO4 (monatite), CaHPO4 · 2H2O (brushite), Ca5(PO4)3OH (hydroxyapatite) and amorphous calcium phosphate. It is interesting to note that hydroxyapatite and brushite were obtained at a low temperature of 60 °C in a very short period of time (30 min). All samples were characterized by X-ray diffraction and scanning electron microscopy.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering