Preparation and characteristics of hydroxyapatite whiskers by homogeneous precipitation method

Hydroxyapatite whiskers were prepared by the homogeneous precipitation method. Soluble calcium ion and phosphate ion were used as initial materials, they were refluxed respectively at 85degreesC, 90degreesC and 95degreesC for various lengths of time. A proper precipitation agent was selected to control the releasing speed of ions m the system; it induced the hydroxyapatite crystal to grow in a desired way. The pH values of each solutions were measured continuously during the reaction. After the reaction, the products were characterized by X-ray powder diffractometry (XRD), scanning electron microscopy (SEM) and infrared spectroscopy (IR). It is shown that long hydroxyapatite whiskers were obtained under the conditions of 95degreesC - 48 h and 90degreesC - 72 h, 85degreesC - 120 h.