Syntheses and characterization of new organically grafted silica foams

In this study, new hybrid Organo-Si(HIPE) macrocellular foams have been synthesized via sol–gel process, direct emulsions and lyotropic mesophases as templating agents followed by a final grafting process of silane organically modified. A variety of sililated groups, including methyl, benzyl, amines, mercapto, pyrrol and dinitro have been successfully grafted. The effects of the various organosilanes on the physical chemical properties of the resulting materials have been thoroughly characterized using several analytical techniques (SEM, TEM, SAXS, mercury porosimetry, nitrogen adsorption isotherms, FTIR, 29Si MAS NMR). If the resulting grafted compounds, labeled gOrgano-Si(HIPE), exhibit the same macroscopic texture than the starting silica open-cell matrices, we found a reduction of the mesoporosity depending upon the size of the organic moiety in use and the associated enhance molecular hindrance. Final porous materials functionalized at the molecular level are potential outstanding candidates for applications such as heterogeneous catalyst, scavenger and sensor.