Related physicochemical, rheological, and dielectric properties of nanocomposites of superparamagnetic iron oxide nanoparticles with polyethyleneglycol

Abstract

ABSTRACTIn this study, we present the physicochemical, rheological, and dielectric properties of the superparamagnetic iron oxide nanoparticles (SPIONs) coated with polyethyleneglycol (PEG). It was observed that the increase of the concentration of PEG prohibited the sedimentation of nanoparticles, which increased the colloidal stability of nanocomposites. The surface study of the polymer and the nanocomposites using TOF‐SIMS showed that the samples did not have the same surface properties. The analysis of the intensity ratios of the FeO+/Fe+ and OH−/O− peaks of the nanocomposites of bare, positively, and negatively charged SPIONs with PEG revealed that no reduction occurred for these nanoparticles when coated with PEG, whereas the iron atoms on the surface of PEG negatively charged SPIONs were less oxidized than those on the surface of PEG‐bare SPIONs, and the iron atoms on the surface of PEG positively charged SPIONs were more oxidized than the second ones. The rheological study of the polymer and the nanocomposites revealed that the presence of SPIONs did not change the rheological behavior of PEG. The analysis of the dielectric properties of PEG and its composites with SPIONs showed that when SPIONs particles (bare and positively charged) were included in PEG, low frequency dispersion (LFD) was strongly enhanced, that the iron oxide nanoparticles reduced the impedance of PEG in the nanocomposites and that the difference in their surface charge affected their impedance. Taken together, these results suggest that the nanocomposites of PEG with SPIONs have appropriate properties for fluid modification and applications in the nanotechnology and photovoltaic devices. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48280.