The micromorphology of the hydrogel was studied using scanning electron microscopy (SEM). The SEM images showed a dense and uniform structure with no obvious pores above 1 μm. The addition of chitosan (CS) to polyvinyl alcohol (PVA) increased the formation of porous structures, which was due to the ice crystals produced during freezing. The addition of CS also increased the number of polymer chain aggregates, which was confirmed by resonance light scattering (RLS) spectra. The self-healing properties of the PVA-CS/TA hydrogels were evaluated using tensile testing, and the results showed that the hydrogels with a higher CS content had better self-healing properties. The microscopic self-healing behavior of the PVA-CS/TA0.5 hydrogel was also studied using optical microscopy, and the results showed that the fissures were well-restored over time. The static self-healing efficiency of the PVA-CS/TA0.5 hydrogel was evaluated, and the results showed that it reached 84% within 2 hours. The molecule structure of PVA, TA, and CS was also discussed, and the self-healing mechanism was proposed to be due to the formation of hydrogen bonds and electrostatic interactions between the three molecules.
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