Preparation and characterization of porous silica templated by a nonionic fluorinated systems

Taking advantage of our experience in the field of fluorinated surfactants, we report the preparation and characterization of both large pore mesoporous and macroporous silica by using fluorinated systems. Here, in particular we have investigated in detail the effect of fluorocarbon solubilization on the properties of materials. Our results show that the various investigated systems can be used for the synthesis of large pore mesoporous materials. Nevertheless, depending on different surfactants, we have to consider two different swelling mechanisms. Indeed, concerning RF8(EO)9, the pore size expansion occurs via the swelling of surfactant-silica hybrid mesophase. On the contrary, for the compounds prepared from RF7(EO)8, the mesopore enlargement takes place through the swollen micelles. In addition, macroporous silica could be design by using fluorinated emulsions as template. Our study also reveals that the formation of macroporous materials is correlated to the phase inversion temperature. We presume that the system with high PIT value conduce the formation of macroporous materials.