To prepare Silica Aerogel the Sol-gel process is used. The chemical step is the first one to obtain a gel in alcoholic or acetonic medium. The aim of this work is the study of the influence ofsuch physico-chemical parameters on gel preparation and specially the acido-basic catalyst which gaverns the two steps of sol-gel process. For all precursors used (TMOS, TEOS et PEDS-Px) a reactionnal mecanism was given. Eventually the gelation time and the ageig of the gel were studied.
E. El Aloui, G.M. Pajonk
Sol-gel process, Silica, catalyst, precursors