ChemInform Abstract: Sol—Gel Synthesis of Amorphous Calcium Phosphate and Sintering into Microporous Hydroxyapatite Bioceramics.

✍ Scribed by P. LAYROLLE; A. ITO; T. TATEISHI

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 36 KB
• Volume: 29
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199838294

✦ Synopsis

Sol-Gel Synthesis of Amorphous Calcium Phosphate and Sintering into Microporous Hydroxyapatite Bioceramics.

-An amorphous, nanosized, and carbonate-containing Ca phosphate powder (Ca:P ratio of 1.67) is synthesized from Ca(OEt) 2 and H 3 PO 4 in ethanol via sol-gel process. The powder is pressed at 98 MPa into green sheets and then heated to a temp. range of 500-1300 • C. At 600 • C the powder crystallizes to a carbonated hydroxyapatite and a trace of β-tricalcium phosphate before converting to hydroxyapatite, Ca 10 (PO 4 ) 6 (OH) 2 , at 900 • C. The thermal crystallization is associated with grain growth, shrinkage, and active surface diffusion. The activation energy of grain growth is 37 kJ/mol. After sintering at 1100 • C, the decomposition of carbonated hydroxyapatite generates a microporous ceramic with an average pore size of 0.2 µm and an open porosity of 15.5%.

-(LAYROLLE, P.;