posted on 2024-06-25, 14:36authored byXin Gao, Jilin Su, Chang Xu, Shichun Cao, Shijia Gu, Wei Sun, Zhengwei You
Elastic electromagnetic fibers are
promising building blocks for
next-generation flexible electronics. However, fabrication of elastic
fibers is still difficult and usually requires organic solvents or
high temperatures, restricting their widespread applications. Furthermore,
the continuous production of electromagnetic fibers has not been realized
previously. In this study, we propose an ionic chelation strategy
to continuously produce electromagnetic fibers with a magnetic liquid
metal (MLM) as the core and elastic polyurethane as the sheath in
water at room temperature. Sodium alginate (SA) has been introduced
to rapidly chelate with calcium ions (Ca2+) in a coagulation
bath to support the continuous spinning of waterborne polyurethane
(WPU) as a sheath. Meanwhile, WPU-encapsulated MLM microparticles
efficiently suppress the fluid instability of MLM for continuous extrusion
as the core. The resultant fiber exhibits excellent mechanical performances
(tensile strength and toughness up to 32 MPa and 124 MJ/m3, respectively), high conductive stability in large deformations
(high conductivity of 7.6 × 104 S/m at 580% strain),
and magnetoactive properties. The applications of this electromagnetic
fiber have been demonstrated by conductance-stable wires, sensors,
actuation, and electromagnetic interference shielding. This work offers
a water-based molecular principle for efficient and green fabrication
of multifunctional fibers and will inspire a series of applications.