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.

This paper reports the improvement of the mechanical properties of epoxy/nanoclay/multi-walled carbon nanotube (MWNT) nanocomposites prepared by the solution casting method for a range of pre-cure temperatures (room temperature, 50, and 70 °C), cure temperature (120, 130, and 140 °C), nanoclay content (0.5, 1.0, 1.5 wt%) and content of MWNT (0.2, 0.6, 1.0 wt%) for three levels. The influence of these parameters on the mechanical properties of epoxy/nanoclay/MWNT has been investigated using Taguchi's experimental design. The output measured responses are the tensile properties (tensile modulus, tensile strength and strain at break), impact strength and fracture toughness. From the Analysis of Mean (ANOM) and Analysis of Variance (ANOVA), MWNT content, pre-cure temperature and cure temperature had the most significant effects for the impact strength with contribution percentages of 38%, 28% and 23% respectively. However, for the fracture toughness and strain at break, the enhancements of properties come from the nanoclay content (59%), MWNT content (18%) and pre-cure temperature (23%). While the improvement in tensile strength was influenced by nanoclay and MWNT content, the cure temperature has a stronger effect on the tensile modulus. In this respect, Taguchi method points to the Taguchi method, in this way, points to the dominant parameters and gives the optimum parameter settings for each mechanical property. Confirmation experiments were performed with the optimum parameter settings and the mechanical properties were measured compared with the predicted results.