Flexible anisotropic magneto-sensitive elastomer films with out-of-plane particle chain for bionic actuator

Owing to the flexible and controllable characteristics, the magnetic composite film becomes an ideal option for future portable, efficient and multifunctional magnetic soft actuators. Here, an anisotropic magneto-sensitive elastomer film (MSEF) composite based on polydimethylsiloxane (PDMS) and high concentration of carbonyl iron particles (CIPs) was developed. The off-plane design of CIP structures endows MSEF excellent field-dependent deformability and actuation ability. The off-plane bending angle of the MSEF-30° in 87mT uniform magnetic field could reach 70.78°. Moreover, the MSEF-20° could lift a heavy object 66.4 times its own weight. The influences of particle chain orientation, CIP contents, thickness and applied magnetic field on the magneto-induced deformation behavior were fully discussed, and finite element calculations were performed to clarify the experimental results. An improved balance equation was proposed and qualitatively explained the experimental results under different magnetic fields. Based on the MSEF composite, biomimetic soft actuators with bidirectional deformation and self-sensing functions were produced respectively. The two easy preparation and programmable soft actuators could achieve the expected actuation effect, indicating that the anisotropic MSEFs have great potential as soft actuators in the fields of biomedicine, microfluidics, intelligent robots and bionics applications.