【作者】 杨为中；

【导师】 周大利； 尹光福；

【作者基本信息】 四川大学 ， 材料学， 2003， 硕士

【摘要】 磷灰石／硅灰石生物活性玻璃陶瓷（AW GC）材料是一种力学性能、生物活性和生物相容性非常优异的材料，长期以来，作为人体硬组织的修复和替代材料为人类健康水平的提高发挥了重要的作用。AW生物活性玻璃陶瓷材料一般通过传统的熔融法制备基础玻璃，再经陶瓷工艺对玻璃进行热处理析晶得到。本研究在国内首创溶胶—凝胶法制备AW生物活性玻璃陶瓷前驱体粉的新工艺。 实验按组成MgO4.6、CaO44.9、SiO₂34.2、P₂O₅16.3、CaF₂0.5（wt％）配方，通过筛选实验确定选用正硅酸乙酯、磷酸三乙酯、硝酸钙、硝酸镁、氟氢化铵为原料，加料顺序为依次加入，最终可获得均匀、清澈、稳定性好的溶胶。研究证明体系温度升高有利于形成凝胶，适宜的温度为50～60℃；体系的pH值对凝胶化也有一定影响，当PH值为5～6时，凝胶化的过程能迅速完成。实验中对凝胶的陈化温度为60℃（50h），干燥温度为180℃（48h），所得干凝胶在500～550℃进行煅烧，经325目筛筛分后可以获得粒度分布均匀、分散性好及反应活性高的非晶态前驱体无机粉末。 干压成型中使用3～4wt％的聚乙烯醇水溶液作为有机粘合剂，粘合剂加入量为10～20wt％，致密型柱状或片状试样的加压压力为10MPa。最佳的烧结温度宜控制在1250℃，保温时间为3h，在此温度下烧成的试样其X衍射图谱得到了所期望的磷灰石晶相和硅灰石晶相的衍射峰；相应FTIR图谱可以分析出磷灰石和硅灰石的结构特征。扫描电镜分析显示此种材料具有微观的孔隙结构，抗压强度实验证明其抗压强度达45MPa，能满足骨修复材料的力学强度要求。 将前驱体粉末锻烧之后再添加造孔剂压制成型，最后锻烧除去造孔剂和有机粘合剂得到孔隙结构。造孔剂硬脂酸颗粒粒径为20～30目，其加入量为 30～40Wt％，多孔材料的孔隙率为 45～55％，所得陶瓷体微观孔与宏观孔相结合、孔隙相互连通，微孔尺寸约 in m，大孔尺寸约 400 u m。材料的孔隙特征和贯通状况有利于骨组织的长入。初步研究证明溶胶一凝胶法制备的A．W玻璃陶瓷化学稳定性好，且能在材料表层形成大量磷灰石晶粒，进而形成表面磷灰石层，因而具有生物活性。 初探了AW／p—TCP复合材料的工艺制备过程，初探了大鼠骨髓基质干细胞／AW生物活性玻璃陶瓷复合材料及大鼠骨膜成骨细胞／AW生物活性玻璃陶瓷复合材料的制备，并预计它们在骨组织工程领域将具有广阔的应用前景。更多还原

【Abstract】 Apatite/Wollastonite bioactive glass-ceramic(AW GC) is a type of biomaterials with excellent mechanic properties, bioactivity and biocompatibility. For a long time, AW GC has played an important role for improving the health level of human being as a bone repairing and replacement material. Traditionally, AW GC is prepared by the following steps: 1. prepare the parent glass through melt method in a high temperature; 2. Crystallize in the parent glass through proper heat-treatment. This paper pioneered to prepare the predecessor powder of AW GC through sol-gel method, and consequently prepared AW GC and its porous materials.To prepare the predecessor powder of AW GC, the composition was accorded with MgO4.6, CaO44.9, SiO234.2, P2O516.3 and CaF20.5 (wt% ). By screening test, tetraethoxysilane(TEOS), triethylphosphate(TEP), calcium nitrate tetra-hydrate, magnesium nitrate hexa- hydrate and ammonium bifluoride were adopted as the raw materials. They were added in the above listed order. As the result, the uniform, lucid and stable sol was obtained. It was also proved that: 1. the proper temperature improving was favored for gelling, and the suitable temperature was 50-60 ; 2. PH value had some influence on gelling, and gel formation was more rapid when PH value was 5-6. The aging temperature was 60 ( for 50h), and the drying temperature was 180 (for 48h). After the dry gel was calcined in 500-550 , sieved with the griddle of 325 mesh, we obtained the predecessor inorganic powder with good distribution of particle size, gooddispersibility, high reactivity and noncrystalline structure.The powder was molded through pressure molding method with 10~20wt% 3~4wt% PVA aqueous solution being added. Dense samples were compressed in lOMPa, and porous samples were compressed in 5MPa. The best sintered temperature was 1250 , keeping 3 hour. The XRD pattern showed the diffraction peaks of apatite phase and wollastonite phase, which were expected. FTIR spectra also showed the corresponded structure. SEM analyzing proved the microporous structure of the material. Compressive strength of the material reached 45 MPa, which was satisfied to be some bone-repairing biomaterials.To get the materials with macroporous structure, the predecessor powder was sintered, and pore-created, and calcined to get rid of the poreforming material. The poreforming material was the particles of stearic acid of 20-30 mesh. About 30~40wt% of them were added to get the porous materials with 45-55% porosity. The materials had both micro pores and macro pores, which connected together. The size of micro pores was 1 m, and the macro pores was 400 m. The size and the structure feature of the materials would be favor for the incoming of blood vessel and bone tissue. Elementary study proved that much grain of apatite could form in the surface of the materials, and might become apatite layer, which endowed the material with bioactivity.Elementarily studied the preparation process of AW GC / - TCP composite material. Elementarily investigated the preparation of Rat marrow stromal cells(MSC)/AW GC composite and Rat periosteum osteoblast/ AW GC composite. These composites were expected to have bright application potential in bone tissue engineering.更多还原