Glass-ceramic powders with the oxide batch formulation 54wt%SiO
2, 20wt%P
2O
5 and 30wt%CaO were prepared by the sol-gel process using tetraethoxysilane, calcium nitrate and phosphoric acid as raw materials. The obtained gels and powders were characterized by TG-DTA thermal analysis, FTIR analyses and XRD measurements. The results indicated that (1) heating to more than 600°C brought about elimination of -OC
2H
5 side chains from gels, and formation of a SiO
2-based glass network, (2) crystallization such as Ca
3(PO
4)
2 notably occurred in the SiO
2-based glass matrix when heated to more than 900°C, (3) -OH groups existed on SiO
2-based glass-ceramic surfaces in the temperature region less than 900°C, and (4) the melting point of this composition was more than 1400°C. This study suggests that sol-gel-derived SiO
2-based glass-ceramic powder containing P and Ca might be useful as bioactive implant materials.
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