Magnetorheological elastomers with efficient electromagnetic shielding

This study is concerned not only with an investigation of rheological performance of magnetorheological elastomers (MREs) with random distribution based on modified magnetic particles, but also discusses their electromagnetic shielding properties for the first time. The current work further highlights the necessity of magnetic particles protection against oxidation species affecting them in real application conditions. Two kinds of MREs differing in matrix type represented by silicone elastomer and thermoplastic elastomer are prepared, and pristine carbonyl iron (CI) particles and siloxane-modified CI particles were used for each matrix. The difference in magnetic properties after the modification of particles is negligible while the modification significantly improves the anti-acid-corrosion properties. Moreover, modification of particles surface enhances their compatibility with silicone elastomer matrix which is evidenced by the measurements of viscoelastic properties under the external magnetic field applied. It is also shown that all the developed MREs can be successfully applied for the absorption of electromagnetic radiation in ultra-high frequency band, namely the frequency range from 700. MHz to 1.6. GHz can be readily covered by these materials. © 2015 Elsevier Ltd.Grant Agency of the Czech Republic [14-32114P]; Operational Program Research and Development for Innovations - European Regional Development Fund (ERDF); national budget of the Czech Republic, within Centre of Polymer Systems [CZ.1.05/2.1.00/03.0111