Tannic acid/polyvinyl alcohol/2-hydroxypropyl trimethyl ammonium chloride chitosan double-network hydrogel with adhesive, antibacterial and biocompatible properties

Hydrogels have great potential for biomedical applications. However, there are still significant challenges in preparing biomass-based hydrogels with excellent adhesive, antibacterial and biocompatible properties. In this study, pure physically cross-linked tannic acid (TA)/polyvinyl alcohol (PVA)/2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC) double-network (PVA/HACC-TA) hydrogels are prepared by a combination approach of cyclic freeze-thaw and soaking method. The prepared PVA/HACC-TA hydrogels are formed by hydrogen bond cross-linking and do not use any toxic and harmful cross-linking agents. Meanwhile, the prepared PVA/HACC-TA hydrogels have excellent mechanical properties, the maximum tensile strength can reach 4.13 MPa and the maximum tensile strain can attain 830%. In addition, PVA/HACC-TA hydrogels display good adhesion to different materials. At the same time, the PVA/HACC-TA hydrogels also show favorable antibacterial activities. Therefore, the excellent mechanical, adhesive, antibacterial and cytocompatible biomass hydrogels showed promising potential applications in the biomedicine field, especially as the skin wound dressings.