Dresden 2011 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 36: Poster: Nanoparticles and Composite Materials

CPP 36.4: Poster

Mittwoch, 16. März 2011, 17:00–19:00, P2

Determination of the intrinsic permeability of nanoparticles in composites with unknown microstructure — •Béatrice Hallouet and Rolf Pelster — FR 7.2 Experimentalphysik, Universität des Saarlandes, Campus E 26, D 66123 Saarbrücken, Germany

In general the details of the microstructure in nanocomposites are unknown. Nevertheless there is a need to determine the intrinsic properties of the dispersed phase, e.g. the permeability of nanoparticles, from the measured effective properties of the system. Due to the unknown microstructure a tentative analysis using simple mixture formulas can be highly erroneous. We present a method to extract at least a partial information about the intrinsic permeability of the particles from the measured spectra. Combining dielectric and magnetic measurements we are able to convert the magnetic spectra into lower and upper bounds for the permeability of the particles. The method applies to composites in a frequency range below the interfacial polarisation peak (MWS) and has been tested for magnetic nanocomposites (nanoparticles of magnetite dispersed in a polymer), the permeability spectra of which a ferromagnetic resonance exhibit.