Matrix dependence of the linear viscoelastic region in magnetorheological elastomers

The aim of this work is to study the linear viscoelastic region limit of isotropic magnetorheological elastomers at different compositions and working conditions. Regarding the synthesis process, the matrix and the particle content are analysed. The analysed matrixes are a natural rubber, a silicone rubber and ELASTOSIL® silicone, and three particle contents are synthesised. The influence of the characterisation variables on the linear viscoelastic limit, that is, frequency, external magnetic field and temperature, is also analysed. Strain sweep tests are used to determine the dynamic complex modulus. The loss factor and the storage modulus are analysed to define the linear viscoelastic limit of each isotropic magnetorheological elastomer sample in all the working conditions. The results show that the linear viscoelastic region of the magnetorheological elastomers is defined by the loss factor. Moreover, the volumetric particle content reduces and frequency increases the linear viscoelastic region of all the matrixes, whereas the external magnetic field and the temperature influences are matrix dependent.