Flexible and Stretchable Poly(styrene-butadiene-styrene)/MXene Nanosheet Composite and Coaxial Fibers for Wearable Strain Sensors

Fiber-based strain sensors have become a vital part for wearable electronics owing to their lightweight, flexibility, and easy processing. A poly(styrene-butadiene-styrene) (SBS)/MXene composite and coaxial fiber-based strain sensors were produced through a continuous, facile, and scalable wet-spinning approach, which exhibited both high stretchability and sensitivity. Electromechanical properties displayed that SBS/MXene composite fibers showed extremely high sensitivity (1.63 × 10 4 ), low strain detection (0.5%), and outstanding durability and reliability, which laid a foundation for detecting human motion including subtle activities, such as breathing and wrist pulse, and large-scale activities, such as bending of limb joints. The strain-sensing performance was further investigated by SBS/MXene coaxial fibers with SBS/MXene as sheath and SBS as core, presenting high sensitivity (4.69 × 10 3 ) and repeatability. SBS/MXene composite and coaxial fiber sensors demonstrated the potential application in wearable electronics with human motion detection.