ECOLOGICALLY COMPATIBLE WATER-BASED MULLITE SOLS, MULLITE COMPOSITIONS AND METHODS OF MAKING THE SAME

摘要

This invention relates to novel ecologically compatible water-based stable mullite precursor sols, mullite composites, and methods for making the same. The mullite precursor sols are synthesized using tetraethoxysilane and aluminum nitrate in water. The tetraethoxysilane is hydrolyzed with water and ammonium hydroxide catalyst to make a silica sol, which is then quenched with an aqueous solution of aluminum nitrate. The mullite precursor sols of the invention may be used to make highly densified ceramic composites.