| 초록 |
Nanostructured organic-inorganic hybrid mesoporous materials have been used as highly functional materials in wide varieties of applications such as optical and electromagnetic devices and metal catalysts. The mesoporous materials are derived with assemblies of supramolecular surfactants or block copolymer as a template. Especially, mesoporous silicates using block copolymer can control pore size and structure as change of block copolymer molecular weight. Between the template and inorganic source it is well known that some mediates is necessary for association with silicate precursors for nonionic templates, however the direct association with silicate precursor is possible for ionic templates. Here, we synthesize new mesoporous materials using quaternized poly(styrene)-block-poly(4-vinylpyridine) (PS-b-P4VP) as a template. Amphiphilic block copolymer, PS-b-P4VP, can be microphase-separated. Moreover P4VPs can be changed with ionic components as quaternization with alkyl-halide, which can directly associate with silicate precursor. PS-b-P4VPs were synthesized by anionic polymerization with various molecular weights and compositions. Quaternization of PS-b-P4VPs was performed with alkylhalide(CH3I) and degree of quaternization depending on different quaternizing agents was calculated by combining FT-IR and nuclear magnetic resonance(NMR). Packing structure and pore size of mesoporous silicates using quaternized PS-b-P4VPs were characterized by small angle x-ray scattering(SAXS). transmission electron microsocope(TEM) and Brunauer Emmett Teller(BET) method. |
