Dresden 2003 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 20: POSTER A
CPP 20.47: Poster
Montag, 24. März 2003, 19:00–21:00, ZEU/250
Reconformation and Metallization of Unimolecular Micelles in Controlled Environment — •Anton Kiriy1, Ganna Gorodyska1, Sergiy Minko1, Constantinos Tsitsilianis2, and Manfred Stamm1 — 1Institut fuer Polymerforschung Dresden, Hohe Strasse 6, 01069 Dresden — 2Department of Chemical Ingineering, University of Patras, 26500 Patras, Greece
Micellezation of star shaped polysterene/poly(2-vinylpyridine) (PS7-P2VP7) block copolymer have been studied by means of atomic force microscopy. PS7-P2VP7 undergo diverse conformational transition response to external stimuli. At certain concentrations PS7-P2VP7 exists in molecularly dissolved state in both selective (acid water, toluene) and non-selective (chloroform, tetrahydrofurane) solvents. In acid conditions PS7-P2VP7 form either unimolecular micelles or multimolecular one dependent on pH. Size of unimers dissolved in acid water can be reduced by addition of Na3PO4. PS7-P2VP7 undergo reverse intramolecular segregation upon addition of toluene. In this case P2VP constitute the dense core whereas PS form an extended shell of reverse unimolecular micelles. Metallization of unimers adsorbed onto silica wafers from acid water by Pd leads to star-shaped nanocomposites in which several nanometers palladium clusters are localized in the outer shell of unimers. Such stimuli-responsive nanoparticles can be used as a drug delivery systems and for nanoelectronics needs.