| 초록 |
Small angle neutron scattering (SANS) was used to investigate the formation of the mesoscopic ordering of the sol-gel solutions of tetraethyl orthosilicate (TEOS) with amphiphilic triblock copolymer poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (EO20PO70EO20, numbers in subscripts denote the molar ratios of each component). Based on small angle X-ray scattering (SAXS) and transmission electron microscope (TEM) results, the mesostructures were strongly influenced by silica / polymer ratio and the amount of hydrochloric acid used for inducing electrostatic interaction to nonionic route (SoIo). The formation mechanism of the micellar ordering and supramolecular cooperative self-assembly was postulated based on the SANS data monitored at various reaction times during sol-gel reaction which showed that a long-range liquid crystal-like mesoscopic ordering of the micelles of EO20PO70EO20 was collapsed shortly after being mixed with the prehydrolyzed inorganic solution, but it was gradually recovered during evaporation of the mixed solvents of D2O and ethanol to facilitate the condensation of silanol group in inorganic framework phases.
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