Abstract
As hydrolyzed in 10 mass% NaOH solution at 75 oC for 1h, the nano-size hydroxyapatite (HA) powders were obtained through a synthesis process using dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD) and CaCO3 as starting materials. For the HA powders synthesized only from DCPD and heat treated at 600 oC for 4h, the phase formed was hydroxyapatite for which the crystallinity was improved with the heat treatment time increasing. On the other hand, the crystallinity of HA powder formed from DCPD excelled that from the DCPD with CaCO3 additive at a Ca/P ratio of 1.67, the latter has the crystal phases of HA and CaO as heat treated at 600 oC for 4h. The morphology of HA formed from DCPD has a well one dimension aligned of nano-particles, but the additive CaCO3 inhibits the aligned phenomenon of the nano-particles.Keywords: hydrolysis, nano-size, hydroxyapatite, CaHPO4·2H2O (DCPD), CaCO3.
