LAUSR

Due to their self-recovery ability and fatigue resistance, double-network (DN) hydrogels with hybrid ionically-covalently crosslinking have received wide attention. In this work, by a simple "one-pot" method, a novel kind of hybrid ionic-covalent chitosan/polysulfobetaine (CS/PSBMA) double-network hydrogels was prepared. The hydrogels showed high tensile strength (2.0 MPa), strong elastic modulus (0.5 MPa), fast self-recovery ability as well as excellent fatigue resistance and high mechanical strength and toughness retention rate after soaking in water for 24 hours. Additionally, the mechanical properties of the DN gels were enhanced after stretch and relaxation because of the rearrangement of chitosan network. More excitingly, due to the antifouling feature of PSBMA and the inherent anti-bacterial property of chitosan, the hybrid DN hydrogels demonstrated a "repel and kill" effect on microorganisms. The CS/PSBMA DN hydrogels may find potential applications in biomedical fields, such as artificial connective tissues, implantable devices and wound dressing.