Pereira M M, Jones J R, Orefice R L, Hench L L
Department of Materials, Imperial College London, UK.
J Mater Sci Mater Med. 2005 Nov;16(11):1045-50. doi: 10.1007/s10856-005-4758-8.
A new class of materials based on inorganic and organic species combined at a nanoscale level has received large attention recently. In this work the idea of producing hybrid materials with controllable properties is applied to obtain foams to be used as scaffolds for tissue engineering. Hybrids were synthesized by reacting poly(vinyl alcohol) in acidic solution with tetraethylorthosilicate. The inorganic phase was also modified by incorporating a calcium compound. Hydrated calcium chloride was used as precursor. A surfactant was added and a foam was produced by vigorous agitation, which was cast just before the gel point. Hydrofluoric acid solution was added in order to catalyze the gelation. The foamed hybrids were aged at 40 degrees C and vacuum dried at 40 degrees C. The hybrid foams were analyzed by Scanning Electron Microscopy, Mercury Porosimetry, Nitrogen Adsorption, X-ray Diffraction and Infra-red Spectroscopy. The mechanical behavior was evaluated by compression tests. The foams obtained had a high porosity varying from 60 to 90% and the macropore diameter ranged from 30 to 500 microm. The modal macropore diameter varied with the inorganic phase composition and with the polymer content in the hybrid. The surface area and mesopore volume decreased as polymer concentration increased in the hybrids. The strain at fracture of the hybrid foams was substantially greater than pure gel-glass foams.
一类基于在纳米尺度上结合的无机和有机物质的新型材料近来受到了广泛关注。在这项工作中，将制备具有可控性质的杂化材料的想法应用于获得用作组织工程支架的泡沫材料。通过使酸性溶液中的聚乙烯醇与原硅酸四乙酯反应来合成杂化物。无机相也通过掺入钙化合物进行改性。使用水合氯化钙作为前体。添加一种表面活性剂，并通过剧烈搅拌产生泡沫，在凝胶点之前将其浇铸。加入氢氟酸溶液以催化凝胶化。将发泡的杂化物在40℃下老化并在40℃下真空干燥。通过扫描电子显微镜、压汞法、氮吸附、X射线衍射和红外光谱对杂化泡沫进行分析。通过压缩试验评估力学行为。所获得的泡沫具有60%至90%的高孔隙率，大孔直径范围为30至500微米。模态大孔直径随杂化物中的无机相组成和聚合物含量而变化。随着杂化物中聚合物浓度的增加，表面积和中孔体积减小。杂化泡沫的断裂应变明显大于纯凝胶 - 玻璃泡沫。
