This study developed a new kind of self-healing polyurethane hydrogels（SPUGs） through a synergistic crosslinking strategy combining dynamic covalent disulfide bonds and non-covalent hydrogen bonds. A specifically synthesized quadrifunctional crosslinker， 3，3'-disulfanediylbis（propane-1，2-diol）， was employed to react with poly（ethylene glycol）-based polyurethane prepolymers， followed by solvent-exchange method to produce SPUGs. The physicochemical properties of SPUGs and lyophilized gels（DSPUGs） were characterized comprehensively， and the results revealed that the dual-crosslinked systems exhibited enhanced thermal stability［temperature at 5% mass loss（T5%）>250 ℃］ and low glass transition temperature（Tg<0 ℃）. With the increase of disulfide bond content， the surface hydrophilicity and equilibrium swelling ratio of SPUGs reduced， while water-retaining capacity increased. Mechanical tests demonstrated that SPUGs exhibited elastic deformation and possessed outstanding tensile properties， compressive toughness and fatigue-resistant capacities. SPUG-II with a moderate crosslinking density achieved a maximum tensile strength of 112.2 kPa， elongation at break of 459.4% and fracture toughness of 267.6 kJ/m3. The double dynamic bonds endowed SPUGs with high self-healing efficiency（≥90% at 50 ℃ for 2 h） and redox-triggered reversible gel-sol transitions. Methyl thiazolyl tetrazolium（MTT） assays confirmed favorable cytocompatibility with cell survival rate exceeding 80% after 72 h incubation. The SPUG hydrogels with superior mechanical properties， reversible gel-sol transitions， high self-healing capability， and good biocompatibility indicated promising prospects in biomedical applications.
