Controlled Regulation of Antibacterial and Degradable Performance via Host (Cyclodextrin)–Guest (Vanillin) Multilevel Structures

The development of biobased polymeric materials is expected to reduce dependence on nonrenewable resources. However, the controlled regulation of performance via host–guest multilevel structures remains a great challenge. To tackle this challenge, host–guest block copolymers (P(CD)₂-b-P(VMA)_x, x = 7, 10, 72, 159) were fabricated by reversible addition–fragmentation chain transfer (RAFT) block copolymerization using β-cyclodextrin-derived monomer and biomass-derived vanillin monomer as the host–guest building blocks. In parallel, P(CD)₂-b-P(VMA)_x self-assembled in situ into honeycomb nanoporous channel materials via two-dimensional (2D) mechanical interlocking and three-dimensional (3D) physical cross-linking. Notably, high cross-linking density (x = 7, 10) showed 89.0% against both E. coli and S. aureus and complete hydrolysis of the ester bonds of host–guest building blocks on the copolymer chain, while low cross-linking density (x = 72, 159) had no antibacterial activity and was partially hydrolyzed. Overall, this strategy showcases an approach for regulating the multilevel structures, providing an eco-friendly material with adjustable properties.