【作者】 王莉丽；

【导师】 赵康；

【作者基本信息】 西安理工大学 ， 材料学， 2005， 硕士

【摘要】 多孔羟基磷灰石生物陶瓷以其优良的生物活性在骨组织缺损修复、组织重建、骨病治疗等骨科临床治疗方面具有良好的应用前景。 因此研制一种三维内部连通的具有良好生物活性的多孔体并获得良好的机械性能以满足组织工程学对骨缺损修复的要求就显得尤为重要了。本文通过溶胶-凝胶法来制备HA粉体,利用所得粉体制备多孔HA支架,采用高分子模板浸渍法,以及将其和凝胶浇铸法相结合的新工艺技术一凝胶成型法。通过材料试验机、X射线衍射(XRD)、电子显微镜(TEM)、扫描电子显微镜(SEM)以及体外模拟试验等现代分析测试技术和分析手段对其形貌和性能进行了检测。并将两种方法所得多孔体进行了性能对比分析,获得了制备高性能羟基磷灰石多孔体的新方法。研究结果表明:在溶胶-凝胶法制备羟基磷灰石粉体的过程中,钙磷比是影响粉体相结构和粉体质量的重要参数,钙磷比控制在1. 67是制取高纯度的HA的关键;浓度对羟基磷灰石粉体合成有很大的影响;陈化处理是制备羟基磷灰石粉体的关键步骤。采用高分子模板浸渍法可以得到三维网状开孔结构的多孔HA支架,通过改变循环浸渍次数实现了对孔隙率的可控,通过改变母体模板和将料涂层的厚度实现了对孔径的可控。采用凝胶成型法也可以很好的控制多孔支架材料的孔洞结构、大小、孔分布均匀且内部连通,孔径在300-500um之间。通过改变工艺参数可以控制孔隙率在92%-45%之间变化。获得了良好的机械性能,当孔隙率为45%时,压缩强度达到西安理工大学硕士学位论文SMPa。为了研究制备出的多孔HA支架的生物相容性,进行了体外细胞培养试验,通过扫描电镜观察其表面生长情况。试验结果表明这种内部相互贯通、呈网状孔结构的特点有利于骨细胞的生长,具有良好的生物相容性。关键字经基磷灰石溶胶一凝胶法多孔陶瓷凝胶成型法体外模拟更多还原

【Abstract】 Hydroxyapatite(HA) powder was prepared by sol-gel method with Ca(NO3 ).4H2O and P2O5 ethanol solution. This process was simple and reactants were cheap compared with other methods. The phase structures were studied by XRD. The results showed that 600℃ seemed to be the appropriate temperature to prepare the fine HA powder. The ageing of the sol influenced the purity greatly. The CaO phase was observed in the powder without ageing .The ageing could increase the stabilization of HA. Proportion of Ca/P influenced HA powder’s structure and quality greatly. Proportion of Ca/P was controlled to be 1.67 was the key of preparation of pure HA powder. Concentration was also very important. The higher the concentration was, the lower the sinter temperature was needed. This process was simple and appropriate to produce HA powder in large quantities.In this study, we also reported two novel methods to prepare HA porous scaffolds. One was polymer sponge method, the other was integrating the gel-casting technique with polymer sponge method to prepare HA porous scaffolds. The pore morphology, size, and distribution of the scaffolds were characterized using a electron microscope. The scaffolds prepared by both methods have an open, uniform and interconnected porous structure with a pore size of 300μm-500μm. The later method could prepare HA porous scaffolds with improved mechanical strength compared with the former one.The porous biomaterial was proved to have a good compatible by vitro cellular assay. The osteoblast-like cells were attached and spread well throughout the porous scaffold. Compressive yield strength and the porosity of the open pores in the scaffold could be controlled by changing HA concentration .更多还原