TY  - JOUR
AU  - Xia, X.
AU  - Metwalli, E.
AU  - Ruderer, M.A.
AU  - Korstgens, V.
AU  - Busch, P.
AU  - Boni, P.
AU  - Muller-Buschbaum, P.
TI  - Nanostructured diblock copolymer films with embedded magnetic nanoparticles
JO  - Journal of physics / Condensed matter
VL  - 23
SN  - 0953-8984
CY  - Bristol
PB  - IOP Publ.
M1  - PreJuSER-20189
SP  - 254203
PY  - 2011
N1  - We thank Barbara Russ and Andreas Neubauer for their help during the magnetic measurements and Walter Schirmacher for fruitful discussion. XX thanks the Erasmus Mundus MaMaSELF program for funding. MAR thanks the Bavarian State Ministry of Sciences, Research and Arts for funding this research work through the International Graduate School 'Materials Science of Complex Interfaces' (CompInt).
AB  - Nanostructured diblock copolymer films with embedded magnetic nanoparticles are prepared by solution casting. The diblock copolymer polystyrene-block-polymethylmethacrylate with a fully deuterated polystyrene block of a weight ratio of 0.22 is used as a structure-directing matrix. Maghemite nanoparticles (gamma-Fe2O3) are coated with polystyrene and thus have a selective affinity to the minority block of the diblock copolymer. The hybrid film morphology is investigated as a function of nanoparticle concentration. The surface structure is probed with atomic force microscopy and scanning electron microscopy. The inner film structure and the structure at the polymer-substrate interface are detected with grazing incidence small angle neutron scattering (GISANS). Irrespective of the nanoparticle concentration a well developed micro-phase separation structure is present. From the Bragg peaks observed in the GISANS data a linear nanoparticle concentration dependence of the inter-domain spacing of the micro-phase separation structure is determined. The superparamagnetic and blocking behavior can be explained with a generalized Stoner-Wohlfarth-Neel theory which includes either an elastic torque being exerted on the nanoparticles by the field or a broad distribution of anisotropy constants.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000291433000006
DO  - DOI:10.1088/0953-8984/23/25/254203
UR  - https://juser.fz-juelich.de/record/20189
ER  -