Scalable wet-spun fibers with hierarchical conductive networks toward wearable strain sensors

The development of fiber-based strain sensors with superior strain-sensing performances is fundamentally hindered by the aggregation-driven disruption of conductive networks, and seriously limits their large-scale production. To address the limitation, we introduce a mechanically robust and continuously conductive wet-spun fibers constructed by combination of two parts: (i) dopamine-polystyrene sulfonic acid (DA: PSS)-doped thermoplastic polyurethane (TPU) and (ii) acrylamide-modified single-walled carbon nanotubes (SWCNTs-AM), Ti 3 C 2 T x MXene, and AgNPs. Meanwhile, a cooperative design featuring hierarchical conductive networks and chain-interlocked architecture was presented. Electrostatic interactions and hydrogen bonding within the interpenetrated polymer chains enhance mechanical robustness, yielding a tensile strength of 0.054 MPa, a deformation range exceeding 648 %, and a toughness of 32.87 ± 5 kJ m -3 . The improved charge transport behavior of under dynamic mechanical deformations endowed these conducive fibers with exceptional strain-sensing performances (e.g., high gauge factor (GF = 3048.98)). Notably, they were industrially knitted using a knitting machine to enable comprehensive monitoring of joint movement signals. The resulting knitted fabric demonstrated a rapid response time (45 ms), stable performance under various strains, superior electromagnetic interference (EMI) shielding, and outstanding durability over 6000 cycles at 15 % strain. This paper presents a continuous TPU wet-spun fibers with excellent mechanical robustness and strain-sensing performances based on the hierarchical conductive networks via a wet-spinning technique, which can be knitted into textile fabrics for electromagnetic shielding and wearable sensors. • Illustration of the fabrication of DCTM-Ag wet-spun fibers by a scalable wet-spinning technique. • The construction of hierarchical conductive networks based on the interfacial dynamic interactions between conductive nanomaterials. • Prominent motion capability of as-proposed knitted sensors with electromagnetic and sensing properties.