中文摘要：

以铝粉、盐酸和硅溶胶、聚乙烯醇为原料,去离子水为溶剂,采用溶胶-凝胶法制备了水溶性的莫来石纤维纺丝原液及其前驱体纤维。探讨了纺丝助剂加入量对纺丝原液可纺性的影响,采用红外吸收光谱FTIR和旋转流变仪分别研究了纺丝原液的红外吸收特性和流变学行为,借助XRD表征了前驱体纤维热处理后的物相组成。结果表明,纺丝助剂PVA的加入量为2%-4%时,纺丝原液为剪切变稀的非牛顿型流体,呈现无管虹吸现象;固含量在30%-40%,粘度在4-7 Pa·s时,溶胶可纺性指标25-26 cm/s,纺丝性能最佳;纺丝原液中存在着利于成纤的Al-O-Si的链状结构的线性高分子聚合物。经过1050℃热处理后纤维的主晶相为莫来石。

英文摘要：

The spinning solution for polycrystalline mullite fiber was prepared by sol-gel method,using aluminum powders,HCl and silica sol as raw materials,deionized water as solution. The effect of the amount of PVA on the spinnabiltiy of sol was inspected. The infrared absorption characteristics and the behavior of rheology of the spinning sole were studied respectively by infrared absorption spectra of FTIR and rotational rheometer. The phase composition of the precursor fibers after heat treatment was analyzed with the help of XRD. The results show that the sol is non-newtonian fluid with shear thinning property and presents no tube siphon phenomenon when the amount of additives of PVA is in the range of 2%-4%. The sol with solid content in the 30%-40% and viscosity in the 4-7 Pa · s has excellent spinnability,with sol spinnability index of 25-26 cm /s. In the spinning sol there are linear polymer chain structures of Al-O-Si,which are benefit to spinning. The main crystal phase of fiber calcined at 1050 ℃is mullite.