Regensburg 2010 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 40: Nanoparticles and Composite Materials I
CPP 40.8: Vortrag
Donnerstag, 25. März 2010, 11:30–11:45, H48
Polymer-grafted Silica Nanoparticles: a Structural Characterization in Solution and Bulk — •Mathias Meyer1, Eike Hübner1, Wim Pyckhout-Hintzen1, Jürgen Allgaier1, Aurel Radulescu2, Dieter Richter1,2, Pieter J. in 't Veld3, and Horst Weiss3 — 1Institut für Festkörperforschung, Forschungszentrum Jülich GmbH — 2Jülich Centre for Neutron Science, Garching, Forschungszentrum Jülich GmbH — 3BASF SE, Ludwigshafen
Though nanocomposites with their astonishing properties are of great interest for research and industry, microscopic details of the polymer-interface have been scarcely investigated. Therefore a model system basing on grafted silica nanoparticles is designed and studied. From TEM, SANS and SAXS experiments, particle sizes and their distribution were determined independently. Despite surface stabilization, attractive inter-particle interactions, formerly neglected in literature, lead to small dynamic aggregates, which we described microscopically in a consistent manner. The influence of the grafting density and the chain length and type of the graft as well as of the dispersing medium were investigated in terms of a polydisperse core-shell-type model. Our experimental results are compared to multiscale simulations within an EU FP7 project (NanoModel), focussing on the radial density profile of the polymer shell. Due to our newly developed "grafting to" approach a labelling of the grafted chains is now possible, which allows for the first time to investigate the chain conformation in the shell. Unlike with other grafting methods (i.e. ATRP), also polymers with a low entanglement molecular weight can be grafted to.