Soft matter, sol-gel process and external magnetic field to design macrocellular silica scaffolds

Rational design toward macrocellular silica scaffolds has been reached. The first technique employed is based on the use of concentrated direct emulsions as a macroscale pattern where the final monolith textures can vary upon the oil volumic fraction, emulsification process, and pH conditions. Also, in order to improve void spaces alignment we can make the use of external magnetic field. In this issue, an hydrophobic Ferro-fluid replaces the oily phase. The second approach is rather focussed on a non-static patterning method that allows a complete control over width, length and curvature of the silica foam Plateau's borders. Furthermore, those macroscale void space structurations are associated to secondary mesoscale porosity emerging from aqueous media lyotropic mesophase while the SiO4 tetrahedral statistic connectivity is offering a third microscale porosity. This void space texturation in registry provides finally hierarchically organized monolith-type materials. (c) 2004 Elsevier B.V. All rights reserved.