Regensburg 2007 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 18: Light-Induced Phenomena
CPP 18.4: Vortrag
Mittwoch, 28. März 2007, 15:15–15:30, H40
Molecular tracer diffusion in thin azobenzene polymer layers — •Norman Mechau1,3, Marina Saphiannikova2, and Dieter Neher1 — 1Institute of Physics, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany — 2Leibniz Institute of Polymer Research, Hohe Straße 6, 01069 Dresden, Germany — 3Forschungszentrum Karlsruhe, Institut of Nanotechnology, 76021, Karlsruhe, Germany
Translational diffusion of fluorescent tracer molecules in azobenzene polymer layers is studied at different temperatures and under illumination using the method of fluorescence recovery after photo-bleaching. Diffusion is clearly observed in the dark above the glass transition temperature, while homogenous illumination at 488 nm and 100 mW/cm^2 does not cause any detectable diffusion of the dye molecules within azobenzene layers. This implies that the viscosity of azobenzene layers remains nearly unchanged under illumination with visible light in absence of internal or external forces.