Particle matrix interfacial interaction effect on the viscoelastic properties of electrolyte iron particle based...

The particle-matrix interfacial interaction is studied through the viscoelastic properties in magnetorheological elastomers, comprising 25 wt% of electrolyte iron particles with (MRE25G) and without (MRE25) grease as an additive. The cross-link density (CLD) and electron microscopy images of the MRE25G sample show a decrease in particle-matrix interface interaction compared to MRE25. However, the magnetisation curve remains identical for both MRE25 and MRE25G. The storage (G') and loss modulus (G'') in MRE25 exhibit higher values than that of pure elastomer (MRE0) and MRE25G. The decrement in G'' value in MRE25G suggests decreased interfacial interaction between particle-matrix and the change in the LVE regime in MRE25G. The increased critical strain amplitude by 2 to 2.5 times upon adding grease indicates a higher re-agglomeration rate than de-agglomeration. In zero magnetic field, the cohesive energy increases nearly five times for MRE25G compared to MRE25, demonstrating increased structure stability with strain. The increase in particle-particle interaction due to the reduction in particle-matrix friction has also enhanced the magnetic field-induced effect, the MR effect, by 30% at the highest magnetic field in MRE25G. The creep-recovery results suggest that the elastic stress (EM) remains identical to the magnetic field for MRE25 and MRE25G. At the same time, the Maxwell viscosity for MRE25G is higher than MRE25. Thus, the interface interaction exhibits a higher impact in zero fields and nearly contributes the same to the field.