The field-dependent complex modulus of magnetorheological elastomers consisting of sucrose acetate isobutyrate ester

In this work, epoxidized natural rubber-50 magnetorheological elastomer was synthesized using conventional rubber processing. The ester plasticizer sucrose acetate isobutyrate was then incorporated into epoxidized natural rubber-50 to soften the matrix and to improve the relative magnetorheological effect. The influence of sucrose acetate isobutyrate ester on the microstructures and properties of epoxidized natural rubber-50 magnetorheological elastomers were experimentally investigated. It has been identified that the addition of sucrose acetate isobutyrate ester can reduce the viscosity of the matrix and increase the mobility of magnetic particles in a matrix. The elongation of magnetorheological elastomer was increased by 19%, and the tensile strength was reduced by 17% at 10 wt% content of the sucrose acetate isobutyrate ester. It is observed that the employment of sucrose acetate isobutyrate ester enhanced the thermal stability leading to low degradation of the properties of magnetorheological elastomer. In rheology test, both absolute and relative magnetorheological effects were increased by 0.16 MPa and 23%, respectively, with incorporation of the 7.5-wt% sucrose acetate isobutyrate ester. It is also identified that the storage and loss moduli as well as loss factor are increased as the excitation frequency is increased. It is finally concluded that agglomeration issues in isotropic magnetorheological elastomer which degrade performances of magnetorheological elastomer application devices and systems can be resolved by the addition of sucrose acetate isobutyrate ester to epoxidized natural rubber-50 used in this work.