溶胶-凝胶法制备超细氧化镁陶瓷纤维  

Preparation of superfine magnesia fibre by sol-gel process

作　　者：张春野[1] 沈湘黔[1] 王涛平[1] 景茂祥[1] 

机构地区：[1]江苏大学材料科学与工程学院,镇江212013

出　　处：《耐火材料》2004年第6期389-392,共4页Refractories

基　　金：国家自然科学基金项目(50344035)。

摘　　要：以碱式碳酸镁和柠檬酸为原料,采用溶胶- 凝胶法成功制得超细氧化镁陶瓷纤维,并应用红外光 谱仪(FTIR)分析了胶体的形成;应用DSC分析了凝 胶前驱体的热处理过程;通过XRD、SEM分析和观察 了凝胶前驱体纤维及其于450℃热处理后所得到的 超细氧化镁陶瓷纤维的形貌和结构。结果表明:凝胶 的可纺性主要受合成反应溶液中柠檬酸与镁离子物 质的量比、溶液的pH值及搅拌时间的影响,在柠檬 酸与镁离子的物质的量比为2,溶液的pH值在4.0 ～5.0,搅拌时间为16～18h的条件下,制得的凝胶 具有较好的可纺性;凝胶的热分解经历脱水、分解及 氧化镁的形成3个阶段,前驱体凝胶纤维经450℃保 温0.5h处理后,可得到直径均匀,表面光滑、致密的 超细氧化镁陶瓷纤维,其直径可在1μm以下。The superfine magnesia fibres were successfully prepared with citric acid and magnesium basic carbonate as the starting reagents by using the sol-gel method.The gel formation was studied by Fourier-Transform Infrared Spectroscopy (FTIR).The thermal decomposition for the gel precursor was investigated by differential scanning calorimeter (DSC).The morphologies and structure for the gel precursor fibres and superfine magnesia fibres derived from the thermal decomposition of the gel precursor fibre at 450 ℃ were characterized by Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD).The results show that the gel spinnability was influenced largely by the mole ratio of citric acid to magnesium ions in the solution,pH value and the stirring time.When the mole ratio of citric acid to magnesium ions was 2,solution pH value 4.0~5.0 and stirring time 16~18 h,the gel obtained exhibited excellent spinnability.The dense superfine magnesia fibre with smooth surface,diameter less than 1 μm was prepared after treating the gel precursor fibres at 450 ℃ for 0.5 h.

关 键 词：陶瓷纤维 超细 氧化镁 前驱体 溶胶-凝胶法 DSC分析 可纺性 物质的量比 溶液 FTIR 

分 类 号：TQ174[化学工程—陶瓷工业] TQ343[化学工程—硅酸盐工业]