Design of magnetic elastomer composites with tunable magnetic responses from soft to hard magnetization.

• Isotropic and anisotropic elastomers with tunable responses were investigated. • Magnetic fillings are homologous nanosheets with different magnetic properties. • The internal chain structures of the magnetic elastomers can be controlled. • Magnetic alignment makes composites behave better than isotropic elastomers. Magnetic elastomer composites with tunable magnetic responses from soft to hard magnetization have been synthesized. Co-Ti co-doped barium hexaferrite (BaCo x Ti x Fe 12–2x O 19) nanopowders were used as the filling and polydimethylsiloxane (PDMS) as the matrix. The effects of magnetic field-induced alignment of BaM magnetic particles in the matrix on the properties of the prepared composites have been investigated. For anisotropic magnetic elastomers, the formed chain structure plays a positive role in the enhancement of the shear energy storage modulus of the elastomers. The enhanced energy storage modulus is increased by about 190 % compared with that of the isotropic magnetic elastomers. Due to the magnetic chain structure of the magnetic particles and its effect on the rubber molecular chain, the anisotropic magnetic elastomers can obtain higher magnetic deformation response capability in the direction of the parallel magnetic field. Their research lays a foundation for further designing tunable magnetic flexible sensors. [Display omitted] [ABSTRACT FROM AUTHOR]