Determination of the structure factor of interparticle interactions in the ferrofluid by small-angle neutron scattering

Abstract

Results of the structure and interparticle interaction investigations of polar magnetic fluid with different con-tent of magnetite, which are obtained by small-angle neutron scattering (SANS) are presented in the work. The experiment was performed on small-angle scattering spectrometer YuMO at the Pulsed Reactor IBR-2 in the Joint Institute for Nuclear Research (Dubna, Russia). Polar ferrofluid magnetite/oleic and dodecyl-benzenesulfonic acid/isobutanol was considered. It is shown that the experimental SANS curves are well described by form-factor for polydisperse spherical particles only for ferrofluids with magnetite concentration of about 0.5 vol. %. Signifi-cant effect of structural factors on the SANS spectra was observed for respectively large concentrations of mag-netic material in the volume of ferrofluid. Aggregation of magnetic particles and the molecules of the stabilizer do not occur in the considered concentration range of magnetic material. Experimentally obtained dependences of the effective structure factor as well as the comparison with the theoretical curve calculated for the hard sphere potential in polydisperse approximation are presented in the work.

Keywords

• magnetic fluid
• ferrofluid
• small angle neutron scattering
• structure factor
• the interparticle interaction