| 초록 |
We investigated the kinetics of core-corona inversion in polystyrene-b-poly(4 vinylpyridine) micelles containing various types of metal ions. Monolayer of PS-b-P4VP micelles prepared either on silicon wafer or on mica by spin coating was dipped in metal ion/ethanol(EtOH) solution. The inversion kinetics is completely different, depending on the metal ions dissolved in EtOH. While an instantaneous inversion to PS core micelle occurred in pure EtOH, PVP core micelle maintained at least for the dipping time of 5 min. in silver acetate(AgAc)/EtOH. The microstructural changes during the inversion was monitored with transmission electron microscope (TEM) and atomic force microscope (AFM) as a function of dipping time. Futhermore, we utilize a pre-patterned polydimethylsiloxane (PDMS) stamp to fabricate a chemically modified micropattern of the micelles. The PDMS pre-pattern induced the selective contact of micelles with solvents such as hydrochloric acid, EtOH, resulting in conversion of the PVP core micelles into PS core micelles. The region intact from micro contact stamping can be used as an effective site for metal/metal oxide nano particle synthesis. |
