Effect of carbonyl iron concentration and processing conditions on the structure and properties of the thermoplastic magnetorheological elastomer composites based on poly(styrene- b -ethylene-co-butylene- b -styrene) (SEBS)

Isotropic and anisotropic thermoplastic magnetorheological elastomer (MRE) composites were prepared by melt blending carbonyl iron (CI) particles with poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS) matrix in the absence and presence of a magnetic field. Effects of CI concentration and processing conditions on the microstructure, thermal stability, mechanical properties, viscoelastic properties and magnetorheological properties of these MRE composites based on SEBS were investigated. Adding magnetic CI particles significantly improves the thermal stability and mechanical strength of SEBS matrix, but does not sacrifice the elasticity and toughness. The CI/SEBS composites, prepared with greater CI concentration at higher temperature, longer time and stronger magnetic field for pre-structuring, exhibit higher field induced modulus change and greater magnetorheological effect, due to the strengthening of mutual particle interactions and the formation of longer and more ordered chain structures.