Abstract:Recently, hydrogel has shown great application prospects in the field of flexible wearable sensor, but the simultaneous realization of remarkable tensile, anti- freezing and adhesion features via a facile method remains challenging. In this work, based on intermolecular physical interactions, poly(N-hydroxyethyl acrylamide) (PHEAA) and gelatin (GE) were employed to prepare PHEAA-GE-EG-NaCl hydrogel by adding sodium chloride (NaCl) and ethylene glycol (EG) into the gel precursor solution via a facile “one- pot” method. The universal tensile machine (UTA), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), rotational rheometer (DHR) and electrochemical workstation were used to characterize the structure and properties of hydrogels. The results show the tensile strain of PHEAA-GE- EG- NaCl hydrogel is 1567%. The PHEAA-GE- EG- NaCl hydrogel possesses outstanding anti- freezing capability, it can maintain the excellent stretchability (558%) and conductivity (0.21 S/m) at -30 ℃. Meanwhile, PHEAA-GE-EG-NaCl hydrogel exhibits the excellent adhesion property to different substrates. More importantly, the PHEAA- GE- EG- NaCl hydrogel- based strain sensor has the excellent strain sensitivity and cyclic stability for both large strain and small strain, and it is capable of stably detecting and monitoring both large-scale human motions and subtle physiological signals in a wide temperature range (-30~25 ℃). Therefore, the PHEAA-GE-EG-NaCl hydrogel holds promising potentials as wearable sensor.