溶胶-凝胶法制备纳米羟基磷灰石

Synthesis of Nanometer Hydroxyapatite by Sol-gel Method

目的以四水硝酸钙和磷酸三甲酯为原料,水和无水乙醇为溶剂,采用溶胶-凝胶法合成纳米羟基磷灰石;并对影响溶胶-凝胶形成的工艺条件(溶剂的选择及加入量、溶液的pH值)以及干凝胶的低温燃烧特性进行研究。方法利用乌氏粘度计测定溶胶-凝胶转化过程中溶液粘度的变化;借助TG-DTA研究干凝胶的热历程;通过红外光谱和X射线衍射研究干凝胶燃烧前后组成及其物相的变化,并采用透射电镜观察合成粉末的形貌。结果在溶剂中引入一定量的乙二醇和控制合适的pH值有助于形成稳定、均一的溶胶,生成的干凝胶具有低温燃烧的特性,燃烧后直接生成羟基磷灰石粉末晶体,经焙烧可得到50nm左右、分散良好的纳米羟基磷灰石。结论采用溶胶-凝胶法可以合成颗粒大小均匀、分散性好的纳米羟基磷灰石。

Objective To synthesize nanometer hydroxyapatite(HAP)by sol-gel method from Ca(NO 3 ) 2 ·4H 2 O and PO(CH 3 O) 3 with water and ethanol as solvents and to study the factors that can affect the formation of sol-gel,including the type of solvents,amount of solvents,pH value,as well as properties under the condition of low temperature combustion of dried gel. Methods The viscosities of sol were determined on WU viscosimeter.TG-DTA was used to analyze the thermal procedure of dried gel by increasing temperature.Characterization of the dried gel and powder after combustion were evaluated by X-ray diffraction and infrared spectrum.The morphology of the powder was observed by transmission electron microscopy. Results Stable and homogeneous gel could be obtained at appropriate pH value when ethylene glycol was added into solvent.The dried gel had the feature of low temperature combustion.HAP powder with particle size of50nm was directly prepared. Conclusion Nanometer HAP powder with uniform particle size can be synthesized by sol-gel method.