Sol-gel preparation of MgO fibers

MgO fibers have been prepared using two sol-gel routes. The first employed magnesium carboxylates and the second used magnesium alkoxides as precursors for the sol-gel chemistry. Polyacrylic acid combined with magnesium gave the best results among the carboxylic acids; the products were characterized by excellent rheological properties suitable for the drawing process. In the alkoxide route, gels were formed by the addition of diols or triols to a methanolic solution of Mg(OCH3)(2). Ethylene glycol gave gels which were the most suitable for the extruding process. MgO fibers produced by the alkoxide route with diameter of ca. 50 mu m have a perfectly cylindrical shape, a smooth surface and better mechanical properties than those of the same diameter produced by the carboxylate method.