聚氨酯泡沫转化法制备多孔生物活性陶瓷

Porous Bioactive Ceramic Derived from Polyurethane Foams

采用溶胶-凝胶法制备了生物陶瓷基体粉料,添加自制助熔剂、聚乙烯醇(PVA)、羧乙基纤维素、正丁醇等制成水基浆料。将经水解和表面改性预处理后的聚氨酯泡沫浸渍于浆料中,排除多余浆料后进行干燥和高温烧成处理,获得生物活性陶瓷。实验研究了PVA含量、自制助熔剂含量及烧成温度等因素对试样孔隙率及抗折强度的影响﹔并通过扫描电子显微镜(SEM)分析试样的孔隙结构﹔通过配置模拟体液(SBF)进行试样的生物活性测试,采用X射线衍射(XRD)分析样品矿化前后物相的变化。实验结果表明,添加30wt%助熔剂、0.76 wt.%PVA的样品在烧成温度为1000℃时可以制备出综合性能较好的多孔生物活性陶瓷,其孔隙率为81.35%、抗折强度为2.75MPa。

Bioceramic matrix powders were synthesized by using a sol-gel method, while water based slurries were prepared by adding lab-made flux, polyvinyl alcohol(PVA), carboxyethyl cellulose and n-butanol. Polyurethane foams after hydrolysis and surface modification were impregnated in the slurries and the excess slurries were removed. The samples were then dried and sintered at high temperatures to obtain bioactive ceramics. The effects of PVA content, self-prepared flux content and sintering temperature on porosity and flexural strength of the samples were systematically studied. The pore samples were analyzed b y using scanning electron microscope(SEM), their biological activity was examined by using simulated body fluid(SBF), and the phase changes before and after mineralization were characterized by using X-ray diffraction(XRD). It was found that porous bioa ctive ceramics with promising comprehensive properties can be obtained by adding 30 wt.% flux and 0.76 wt.% PVA, with a sintering temperature of 1000 ℃. The porosity of the optimized sample is 81.35% and the flexural strength is 2.75 MPa.