Effect of Amine Additives on the Morphology of Hydroxyapatite
Long HA whiskers with uniform morphology, high aspect ratio, and good crystallinity could be prepared using a hydrothermal technique at 180 oC for 10 h. Whisker morphology was sensitively-dependent on preparation conditions. Compared with formamide and urea, acetamide showed a low hydrolysis rate; it was found to be an appropriate additive to synthesize HA whiskers. Length and aspect ratio could be controlled by selecting solution conditions with the Ca/P ratio at 1.67 in the range 42 - 84 mmol/L calcium and 25 - 50 mmol/L phosphate and 0.75 – 1.25 mol/L additive concentration (as amide, -NH2).
Guy Daculsi and Pierre Layrolle
H. Q. Zhang and B. W. Darvell, "Effect of Amine Additives on the Morphology of Hydroxyapatite", Key Engineering Materials, Vols. 361-363, pp. 115-118, 2008