Radiofrequency characterization of polydimethylsiloxane – iron oxide based nanocomposites

Colloidal iron oxide nanoparticles with diameters ranging from 15 ± 1 nm up to 29 ± 3 nm are used as pure dielectric fillers for nanoparticles-doped nanocomposites. We show that their superparamagnetic behavior allows them to increase the real dielectric constant of polydimethylsiloxane keeping unchanged the magnetic permittivity. Moreover, all the realized nanocomposites (concentration up to 8 wt.%) show very low dielectric and magnetic losses, suggesting that, at the investigated concentrations, the proposed material can be used as a substrate for electromagnetic circuits in the frequency range between 0.5 GHz and 2.5 GHz.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Iron-oxide nanoparticles are suggested as dielectric fillers for polymer-based nanocomposites. ► Magnetic permittivity is kept very close to pure polymer value. ► Concentration up to 8 wt.% and particles with different diameters are tested. ► Dielectric constant values do not depend on particles diameter. ► Very low dielectric and magnetic losses have been found for all tested samples.