Mesostructured fatty acid-tethered silicas: sustaining the order by co-templating with bulky precursorsElectronic supplementary information (ESI) available. See DOI: 10.1039/c2dt31835k

The co-condensation of functional alkoxysilanes with tetraethoxysilane in the presence of a structure directing agent under sol-gel process chemistry is a common way to access functional organosilica with an ordered mesostructure. In this report, bulky silylated fatty acid methyl esters were used both as co-templating bio-molecules and functionalizing agents in the process of supra-molecular silica mineralization. The highest structural regularity in terms of pore size distribution and channel size homogeneity was observed for carboxy-tethered silica possessing SBA-15-type architecture due to an enhanced fatty acid precursor-surfactant interaction. The carboxylic surface embedded within the hydrophobic environment of the fatty compounds confers to these materials interesting reactive-surface properties with promising applications as drug-delivery systems and bio-catalytic nanoreactors. Despite their bulkiness, the fatty acid precursors can be embedded within the silicates framework without suffering from microphase separation.