材料结晶度对纳米羟基磷灰石表面性能和溶解性能的影响

采用化学共沉淀法合成不同结晶度的纳米羟基磷灰石（ nHAP）粉体，作为对比，用固相法合成体相羟基磷灰石（bulk-HAP）。利用红外光谱（IR）、透射电镜（TEM）或扫描电镜（SEM）以及粉末X射线衍射法（XRD）对羟基磷灰石（ HAP）样品的形貌、晶体结构进行表征。利用溶解实验探索 HAP结晶度与其溶解性能的关系。结果表明，结晶度越小样品的粒径越小，nHAP结晶度明显小于体相HAP的。此外，在恒定 pH（2～7）条件下，nHAP的结晶度越小溶解性能越好，从而能释放出越多的磷酸根，进而表现出越强的反应性能。

The Eeffect of Crystallinity on the Surface Properties and Rreactivity of Nnano-sized Hydroxyaptite

The nano-sized hydroxyapatite（nHAPs ） were synthesized by using precipitation method.For comparison, the bulk samples were obtained by conventional solid-state reaction.XRD, TEM,SEM,IR were used to characterize these HAPs.Results showed that the samples were pure HAP and the size of samples increased with its crystallinities .In addition, determination of dis-solution rates for nHAP was conducted at the controlled pH condition .It was showed that the dissolution was inversely related to pH and the solubility of HAPs increased with decreasing crystallinity of HAP .The more release of phosphorus in the solution , the more reactivity found.