抄録
The objective of this study is to prepare and characterize hydroxyapatite (HAP) particles having hydrophobic surface. Alkylphosphate (AP) was incorporated to the surface of HAP by virtue of electrostatic interaction and/or isomorphous substitution, resulting in formation of hydrophobic surface on HAP. The polar head group of AP was oriented to the HAP while the nonpolar tail group oriented to an aqueous phase. Hydrophobic properties of the surface were discussed mainly by means of contact angle measurement of a water drop placed on the HAP pellet. It was confirmed that various organic and hydrophobic compounds were adsorbed to the surface of the HAP prepared here. The driving force was hydrophobic interaction. The adsorption amount of calcium cation and phosphate anion, which are the component ions of HAP, decreased with the degree of hydrophobicity of the surface, i.e., surface concentration of AP, because nonpolar groups of AP on the surface prevented these lattice ions from approaching to the surface.
