Abstract:
Acrylic acid (AA), acrylamide (AM), silk fibroin (SF), tannic acid (TA), iron oxide (Fe
3O
4) nanoparticles, and two-dimensional MXene nanosheets were used as raw materials. A conductive hydrogel marked as P(AA-
co-AM)/SF/TA-Fe
3O
4@MXene was fabricated via one-pot free radical polymerization in a water/glycerol binary solvent at room temperature. TA-modified Fe
3O
4 nanoparticles anchored on MXene nanosheets (TA-Fe
3O
4@MXene) were employed as functional fillers in a system requiring no external energy supply. The composition, chemical states, and microstructure of the material were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The tensile and compressive mechanical properties and anti-fatigue performance of the hydrogel were evaluated using an electronic universal testing machine. Its wide-temperature stability was assessed by differential scanning calorimetry (DSC). The electrical conductivity and strain-sensing performance were investigated using a digital multimeter combined with a tensile apparatus. The hydrogel exhibits ultrahigh stretchability (1 640%), high tensile strength (282 kPa), high electrical conductivity (206.8 μS/cm), and excellent wide-temperature (−40 ℃ to 60 ℃) stability. As a flexible strain sensor, it demonstrates high sensitivity (gauge factor (GF) of 5.92), good cycling stability, and real-time response to weak physiological signals such as joint motion and throat vibration, showing great potential for flexible wearable electronics.