Study of the structure of nanocomposites based on magnetite and vegetable oil polymeric matrices by SAXS

D. MURACA; O. MOSCOSO LONDOÑO; M. I. ARANGUEN; M. A. MOSIEWICKI; L. M. SOCOLOVSKY; K. R. PIROTA; M. KNOBEL; C. MEIORIN

Buenos Aires

Workshop; BIOPOLI2015; 2015

SAXS experiments allow obtaining the structural correlation length of different materials [1]. In this work, we use this technique to investigate the structure of magnetic nanoparticles (MNPs) included in a non-magnetic matrix. The cluster formation is studied through the fractal aggregate model. These measurements are fundamental to correlate the morphology with other magnetic, thermal and also structural behavior. The knowledge of sizes and spatial distribution of the MNPs allow us to better modeling the results of magnetic properties, which are, size-dependent.MATERIALS AND METHODSMNPs were prepared by a co-precipitation method from an aqueous solution of Fe3+/Fe2+ salts and then coated with oleic acid [2]. The nanocomposites (NCP) were prepared mixing styrene (St) or methyl ester (ME) and tung oil at a weight ratio of 70/30 (TO/comonomer) (S1 and S2, respectively). Other NCPs were prepared by adding acrylated epoxidized soybean oil (AESO) with a weight ratio (TO/modifier) of 90/10 (S3). The mixture was stirred, then the cationic initiator, BF3.OEt2,, was added. The MNPs (1wt.%) were added to the original mixture and subjected to ultrasonication. Finally, the mixed dispersion was poured in a mold and cured in a convection oven [2]. Small-angle X-ray (SAXS) experiments were performed on SAXS beamline at the Brazilian Synchrotron Light Laboratory (LNLS), CNPEM, in Campinas, Brazil.