Bimetallic ions synergistic cross-linking high-strength rapid self-healing antibacterial hydrogel

In this work, a novel PAA-Fe3+-Al3+ hydrogel with triple network structure (TN) was synthesized via bimetallic ions synergistic cross-linking strategy. As-synthesized samples were characterized by scanning electron microscope, Fourier transform infrared analysis, and X-ray diffractometer. The relevant experiment results demonstrated that the hydrogel can rapidly self-heal in ambient temperature without any external stimulus with 95% healing efficiency in 60 s. Simultaneously, the relatively rapid self-healing of PAA-Fe3+-Al3+ polymer can be obtained through the coordination of metal ions with the-COO- in PAA and the oxygen of agar in the TN hydrogel system. And the prepared hydrogels demonstrate excellent mechanical properties-high tensile strength (the tensile strain approximate to 1.011 mm/mm, tensile stress approximate to 0.34 MPa) and large elasticity (the elongation at break approximate to 74%). Especially, the antimicrobial activity of the novel hydrogel against Staphylococcus aureus and Escherichia coli bacteria was investigated using the inhibition zone method, showing remarkable antibacterial activity. POLYM. ENG. SCI., 59:919-927, 2019. (c) 2018 Society of Plastics Engineers