Core-sheath structured polystyrene-ethylene-butene-styrene/carbon nanotubes/carbonyl iron particlecomposite fiber with high stretchability for strain and magnetic field dual-mode sensing

To meet the requirement of high stretchability, high sensitivity, and multifunction for flexible sensors, core-sheath structured polystyrene-ethylene-butene-styrene (SEBS)/carbon nanotubes (CNTs)/carbonyl iron particle (CIP) fiber with SEBS/CNTs as the sheath and SEBS/CIP as the core was prepared through wet spinning. The contents of CNTs and CIP in the composite fiber were adjusted by changing the extrusion speed of the SEBS/CNTs and SEBS/CIP spinning solutions. The morphology, electromechanical sensing, and magnetic precepting performances of the fiber were studied. The SEBS/CNTs/CIP fiber sensor showed high stretchability with a maximum strain sensing range of 0%-216.9%, high sensitivity with a gauge factor (GF) of up to 1068.28, as well as excellent durability. In addition, the SEBS/CNTs/CIP fiber sensor exhibited excellent magnetic sensing performance by changing the relative resistance of 35.2% with a magnetic flux density variation of 1.2 T. The applications of SEBS/CNTs/CIP fiber in stretchable circuits, human body motion monitoring, and magnetic field perception were demonstrated.Highlights center dot SEBS/CNTs/CIP fiber for strain and magnetic field sensing was fabricated.center dot The SEBS/CNTs/CIP fiber sensor could sense 216.9% strain with GF up to 1068.28. Relative resistance of center dot SEBS/CNTs/CIP fiber sensor changed by 35.2% under 1.2 T.center dot SEBS/CNTs/CIP fiber was used in human motion monitoring and magnetic perception.