Patent ID: 6159539
Filing Date: 2000-12-12
Classification: C07F,Y10T

Abstract:
A process for preparing organically modified aerogels, in whicha) a siliceous lyogel or hydrogel is introduced,b) the gel prepared in step a) is optionally subjected to partial solvent exchange with an organic solvent,c) the gel obtained in step a) or b) is reacted in the presence of water with at least one silylation agent, and wherein the water content is about 1% to 25% by weight based on the wet gel,d) the silylated gel obtained in step c) is optionally washed with an organic solvent, ande) the gel obtained in step c) or d) is dried subcritically, which comprises reacting in step c) the gel obtained in step a) or b) in the presence of water with at least one chlorine-free silylation agent of the formula I and/or II, ##STR4## where R.sup.1, R.sup.2, R.sup.3 independently of one another are, identically or differently, hydrogen atoms, unbranched or branched C.sub.1 -C.sub.6 -alkyl, cyclohexyl or phenyl radicals.