title: Arrangement of Maghemite Nanoparticles via Wet Chemical Self-Assembly in PS-b-PNIPAM Diblock Copolymer Films.
abstract: The structure and magnetic behavior of hybrid films composed of maghemite (γ-Fe2O3) nanoparticles (NPs) and an asymmetric diblock copolymer (DBC) polystyrene61-block-polyN-isopropylacrylamide115 are investigated. The NPs are coated with PS chains, which allow for a selective incorporation inside the PS domains at different NP concentrations. Upon incorporation of low amounts of NPs into the DBC thin films, the initial parallel (to film surface) cylinder morphology changes to a well ordered, perpendicularly oriented one. The characteristic domain distance of the DBC is increased due to the swelling of the PS domains with NPs. At higher NP concentrations, the excess NPs which can no longer be embedded in the PS domains, are accumulated at the film surface, and NP aggregates form. Irrespective of NP concentration, a superparamagnetic behavior of the metal oxide-DBC hybrid films is found. Such superparamagnetic properties make the established hybrid films interesting for high density magnetic storage media and thermoresponsive magnetic sensors.
authors.affiliation: †Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching, Germany.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yao
authors.affiliation: †Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching, Germany.
authors.forename: Ezzeldin
authors.initials: E
authors.lastname: Metwalli
authors.affiliation: †Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching, Germany.
authors.forename: Bo
authors.initials: B
authors.lastname: Su
authors.affiliation: †Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Körstgens
authors.affiliation: †Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Moseguí González
authors.affiliation: ‡Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Miasnikova
authors.affiliation: ‡Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany.|§Fraunhofer Institut für Angewandte Polymerforschung IAP, Geiselbergstrasse 69, 14476 Potsdam-Golm, Germany.
authors.forename: Andre
authors.initials: A
authors.lastname: Laschewsky
authors.affiliation: ∥Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Walther-Meissner-Strasse 8, 85748 Garching, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Opel
authors.affiliation: ⊥Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22603 Hamburg, Germany.|#Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, sor Juana Inés de la Cruz 3, Cantoblanco, 28049 Madrid, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Santoro
authors.affiliation: ⊥Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22603 Hamburg, Germany.
authors.forename: Stephan V
authors.initials: SV
authors.lastname: Roth
authors.affiliation: †Technische Universität München, Physik-Department, Lehrstuhl für Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Müller-Buschbaum
keywords: GISAXS; block copolymer; hybrid films; maghemite nanoparticles; nanocomposites