On the organic/inorganic interface between mesoporous SBA-16 silica and its structural directing polymer: a combined FT-IR and solid state NMR study

Abstract

In the last years large attention was devoted to the synthesis and characterization of SBA-16 material focusing the interest on the formation mechanisms of copolymer micelles which drive the organization of the final siliceous mesostructure. However, there are relatively few reports on the block copolymer-silica self-assembly interaction phenomena which mainly occur at solid state and which help to understand how the copolymer is organized in the final solid sample. The physico-chemical properties at the interface between silica framework and triblock EO₁₀₆PO₇₀EO₁₀₆ co-polymer in a SBA-16 material were investigated. In particular, the combination of infrared spectroscopy with solid state NMR allowed to obtain complementary information on how the surfactant co-polymer interacts with the SBA-16 surface silanols in the presence or absence of physisorbed water and to follow the evolution of the structural organization of the co-polymer, which depends on the hydration degree of the SBA-16 sample.