Self-assembly of alkyl-substituted cubic siloxane cages into ordered hybrid materials

Atsushi Shimojima, Ryota Goto, Norimasa Atsumi, Kazuyuki Kuroda

    Research output: Contribution to journalArticle

    54 Citations (Scopus)

    Abstract

    Siloxane-organic hybrids with well-ordered mesostructures were synthesized through the self-assembly of novel amphiphilic molecules that consist of cubic siloxane heads and hydrophobic alkyl tails. The monoalkyl precursors functionalized with ethoxy groups (CnH2n+1Si 8O12(OEt)7, 1Cn, n = 16, 18, and 20) were hydrolyzed under acidic conditions with the retention of the siloxane cages, leading to the formation of two-dimensional hexagonal phases by evaporation-induced self-assembly processes. Analysis of the solidstate 29Si MAS NMR spectra of these hybrid mesostructures confirmed that the cubic siloxane units were crosslinked to form siloxane networks. Calcination of these hybrids gave mesoporous silica, the pore diameter of which varied depending on the alkyl-chain length. We also found that the precursors that had two alkyl chains formed lamellar phases, thus confirming that the number of alkyl chains per cage had a strong influence on the mesostructures. These results expand the design possibility of novel nanohybrid and nanoporous materials through the self-assembly of well-defined oligosiloxane-based precursors.

    Original languageEnglish
    Pages (from-to)8500-8506
    Number of pages7
    JournalChemistry - A European Journal
    Volume14
    Issue number28
    DOIs
    Publication statusPublished - 2008 Sep 26

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    Keywords

    • Amphiphiles
    • Mesoporous materials
    • Nanostructures
    • Self-assembly
    • Silica-based hybrid

    ASJC Scopus subject areas

    • Chemistry(all)

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