Abstract
Biopolymeric films (BFs) offer sustainable packaging alternatives but face limitations in mechanical strength and moisture resistance. This review explores dynamic covalent chemistry via Schiff base reactions (SBRs) as a transformative strategy to enhance BFs. Crosslinking amino-rich biopolymers (e.g., chitosan, gelatin) with aldehyde donors (e.g., dialdehyde polysaccharides, plant aldehydes) improves film stability, barrier properties, and stimuli-responsive behavior. Plant aldehydes serve dual roles as crosslinkers and antimicrobial agents, enabling pH-triggered release to combat spoilage. Advances in polysaccharide/protein-based films demonstrate efficacy in preserving fruits, vegetables, and meats. Innovations like pH-sensitive indicators and respiration-triggered release underscore SBR-engineered films' versatility for active packaging. Challenges in scalability, safety, and industrial integration remain. This work provides a roadmap for next-generation packaging balancing performance, sustainability, and precision preservation.