采用st ber法制备SiO2胶粒,经自然沉降的过程制备SiO2有序模板,再通过HA前驱体溶胶灌注、烧结和碱液浸渍等过程,制备了三维有序多孔羟基磷灰石(HA).采用XRD、TEM、FESEM和Zeta电位对样品的物相、微观结构、孔分布及表面电性能进行研究.结果显示,H2O2表面改性使得SiO2胶粒Zeta电位升高,有利于提高模板的有序性.制备的SiO2胶粒粒径约为250nm,由胶粒形成的多孔羟基磷灰石的孔径约为200nm,孔间由孔径约为20nm的微孔互相连接.此外,还考察了羟基磷灰石前驱体浓度、用量以及碱液浸渍时间对多孔材料的成型、孔结构、孔隙率的影响.当使用的前驱体浓度为0.8mol/L,用量占模板体积的30%,浸渍在4mol/L的NaOH中3d后,形成的多孔HA有序性良好.
SiO2 colloidal template was prepared through St ber method, followed by gravitational sedimentation. Hydroxyapatite (HA) with highly ordered three-dimensional pores was fabricated through infiltrating the template with HA precursor, sintering and then removing the template by immersing in NaOH solution. The samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), field emission scanning electron microscope (FESEM). The effects of the concentration and amount of HA precursor, and the time of immersion in NaOH solution on the preparation technique, the porous structure and the porosity were investigated. The results show that the Zeta potential of SiO2 spheres increase after surface modification by H2 O2, thus improving the order degree of the silica colloidal template. The sizes of SiO2 colloid spheres and the pores formed by dissolved spheres are about 250nm and 200nm, respectively. There are a great number of micro-pores with dimension of 20nm on the wall of the HA pore formed by removing SiO2 spheres. The well-ordered HA with three-dimension pores are fabricated on the condition that the HA precursor concentration is 0.8mol/L, the volume ratio of HA precursor to the whole template is 30%, immersion in 4mol/L NaOH solution for 3d.