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 ≈ 1.011 mm/mm, tensile stress ≈ 0.34 MPa) and large elasticity (the elongation at break ≈ 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. © 2018 Society of Plastics Engineers