POROUS TEXTURE CHARACTERISTICS OF A HOMOLOGOUS SERIES OF BASE-CATALYZED SILICA AEROGELS

Eighteen samples of base-catalyzed silica aerogels obtained using vari ous tetraethylorthosilicate (TEOS) and water contents in the reaction system were characterized using N-2 adsorption. From the observed pore size distribution and adsorption isotherms the volumetric and surface fractal dimensions were determined and also the range of power-law be haviour of the porous network. The porous texture of both the bulk aer ogel and surface of clusters appeared to be dependent on the concentra tion of reactants. The water content, however, emerges as a factor con trolling surface fractal structure, its principal effect being exerted on the pore volume in the mesopore size range.