无机莫来石连续纤维材料制备研究进展

 无机莫来石连续纤维具有良好的热稳定性、化学稳定性及高温强度，因而被广泛用作绝热材料、高温结构材料和纤维增强体，是一类具有重要用途的高温陶瓷材料。莫来石连续纤维制备工艺复杂，影响因素众多，制备较为困难。美日企业已经掌握了莫来石连续纤维的制备工艺并开展了商业化生产，而国内仍集中于低附加值莫来石短纤维的生产，尚未开发出莫来石连续纤维商业化产品。本文系统介绍了溶胶-凝胶、静电纺丝、超细微粉挤出、熔融、内结晶等莫来石连续纤维制备方法的优缺点，总结了国内外在这一领域的近期研究进展，重点论述了溶胶-凝胶法干纺方法的优势；介绍了金属无机盐溶胶-凝胶和金属醇盐溶胶-凝胶两种技术路线，对其中涉及到的溶胶结构、稳定性、助剂作用等关键问题进行了探讨，并展望了莫来石连续纤维制备技术的发展方向。

Research Development for the Fabrication of Inorganic Continuous Mullite Fiber

Inorganic continuous mullite fiber is a widely-used high-temperature ceramic material. It is used as an insulation material, a high temperature structure material, and a reinforcement fiber, because of its excellent thermal stability, chemical stability, and high-temperature mechanical strength. The complexity of processing and numerous other factors pose difficulties for the fabrication of the continuous mullite fiber. The preparation of continuous mullite fiber has been mastered by some foreign companies in the United States and Japan, and lucrative commercial products were made available. China still focuses on the production of short mullite fiber with little added value instead of the continuous fiber. In this paper, the merits and drawbacks of preparation methods of continuous mullite fiber are introduced, including sol-gel, electrospun, extrusion processes and the melting method. Recent progress in this field, both international and domestic, is summarized. Dry-spinning preparation via the sol-gel method is illustrated, and two technical routes, namely, the metal inorganic salt sol-gel and metal alkoxide sol-gel methods, are introduced. The structure and stability of the solution and the effects of spinning additives are discussed. Finally, the development prospects of the sol-gel method are presented.