Electromagnetic functionalized ultrafine polymer/γ-Fe2O3 fibers prepared by magnetic-mechanical spinning and their application as strain sensors with ultrahigh stretchability

A novel magnetic-mechanical spinning method was used to fabricate ultrafine parallel polyaniline/polyvinylidene fluoride/γ-Fe2O3 (PANI/PVDF/γ-Fe2O3) fibers. The magnetic field is generated by a permanent magnet which plays a decisive role in the spinning process. Moreover, the resultant fiber is continuous and the length of the fiber can be tens of meters. Additionally, the fibers are well aligned and the alignment can be maintained. The composite fibers show an electrical conductivity of 6.4 × 10−4 S cm−1 and good superparamagnetism at room temperature. In particular, the strain sensor based on the twisted fibers shows an ultrahigh stretchability up to 440%, and a quick and repeatable response to finger pressure. The electromagnetic functionalized composite fibers may be used in stretchable devices, sensors, or electromagnetic interference shielding.