Natural polyphenol tannin-immobilized composites: rational design and versatile applications

, Mannich reaction, Schiff base reaction, graft copolymerization, oxidation coupling, electrostatic interaction, and hydrogen bonding) between them. Further, the application of tannin-immobilized composites in the biomedical (tissue engineering, wound healing, cancer therapy, and biosensors) and other (leather materials, environmental remediation, and functional food packaging) fields is highlighted. Finally, we conclude with some thoughts on the open challenges and future perspectives of tannin composites. It can be anticipated that tannin-immobilized composites will continuously draw attention from more and more researchers, and further promising applications of tannin composites will be explored.