Goethite nanorods as a cheap and effective filler for siloxane nanocomposite elastomers

Abstract

Iron oxide (goethite) with a nanorod morphology was prepared by a chemical precipitation method and characterized by FTIR, EDX, TEM, WAXD. This was used as an active filler to prepare dielectric elastomer nanocomposites by its incorporation, besides silica, in a silicone matrix consisting in a high molecular weight polydimethylsiloxane-α,ω-diol (PDMS). The nanocomposites were processed as films, stabilized by peroxidic crosslinking at high temperature, and their properties of interest for potential use in the structure of electromechanical devices were studied. It is for the first time that such composites, based on PDMS and iron oxide in a well-defined type (goethite) and shape (nanorods) are approached from the perspective of dielectric elastomers. The introduction of iron oxide nanoparticles into the polymer matrix resulted in improvements in both mechanical and dielectric properties. Thus the breaking strain and the dielectric constant values increased in comparison with those of the pure polymer sample, while the dielectric loss preserved low values specific for dielectrics.