原位反应合成CaO-P_2O_5-SiO_2系生物陶瓷

In-situ reaction synthesis of the CaO-P_2O_5-SiO_2 system bioceramic

以碳酸钙、磷酸和正硅酸乙脂为原料,原位反应合成了CaO P2O5 SiO2系生物陶瓷。研究表明:240℃水热合成8h,在1020℃下烧结2h试样的主晶相为β TCP,次晶相为HA,此外尚含有SiO2。二次水热处理工艺后,多孔生物陶瓷中的颗粒状β TCP向针状缺钙型HA转变,试样的开口气孔率从二次水热处理前的65.5%增加到75.0%,抗压强度从二次水热处理前的1.80MPa提高为2.90MPa。原位形成的针状缺钙型HA晶体提高了多孔生物陶瓷的抗压强度。

The CaOP2O5-SiO2 system bioceramics were prepared by in-situ reaction synthesis from calcium carbonate, phosphonic acid and tetraethyoxysilane (TEOS). It was found that phases of the sample consist of β-TCP as main-crystal-phase, hydroxyapatite as secondary crystal-phase and silicon dioxide by way of both processed at 240'C hydrothermal condition for 8h and sintered at 1020°C for 2h. Further hydrothermal process induces that the sample undergoes a phase-change from grain-like β-TCP to needle-like calcium-deficient hydroxyapatite. At the same time, the porosity increases from 65.5% to 75.0%, the compressive strength enhances from 1.80 MPa to 2.90 MPa. Needle-like calcium-deficient hydroxyapatite created in-situ reinforces compressive strength of the porous bioceramic.