Laby, L., Rutgers - State Univ. of New Jersey, Dept. of Ceramics, P.O. Box 909, Piscataway, NJ 08855-0909, United States
Klein, L.C., Rutgers - State Univ. of New Jersey, Dept. of Ceramics, P.O. Box 909, Piscataway, NJ 08855-0909, United States
Turniansky, A., Hebrew University of Jerusalem, Dept. of Organic Chemistry, Jerusalem 91904, Israel
Avnir, D., Hebrew University of Jerusalem, Dept. of Organic Chemistry, Jerusalem 91904, Israel

Using the sol-gel process, we prepared two types of xerogels. Thin, transparent, crack-free alumina disks were prepared from aluminum tri-secondary butoxide (ASB). Addition of partially hydrolyzed tetraethylorthosilicate (TEOS) to such alumina sols produced translucent, warped silica-containing alumina xerogels. While the pure alumina xerogels were water soluble, addition of silica improved their durability. To understand the change in water solubility, we investigated the chemical and structural changes that occurred when silica was added. Characterization was performed using X-ray diffraction analysis, thermal analysis, nitrogen sorption analysis and 27Al NMR spectroscopy.