Highly Porous Silica Monoliths from Ethyl (L)-Lactate Modified Silanes

Summary. A new type of silica precursor was synthesized by (trans)alkoxylation of alkoxy- and chlorosilanes with ethyl (L)-lactate. This novel ethyl lactate modified silane was hydrolyzed and condensed in the presence of a non-ionic surfactant – poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) triblock copolymer (P123) – to give monolithic silica gels. The wet gels were dried using two different drying techniques resulting in crack-free monoliths: a) supercritical drying with CO₂ to yield a porous inorganic material and b) surface silylation with trimethylchlorosilane to yield an inorganic–organic nanocomposite material. The obtained porous gels were characterized by different techniques including thermal analysis, nitrogen sorption, and electron microscopy (TEM, SEM).