Vanillin cross-linked chitosan/gelatin bio-polymer film with antioxidant, water resistance and ultraviolet-proof properties

Cross-linking is the most promising method for preparing high-performance chitosan/gelatin bio-polymer film. In this work, vanillin cross-linked chitosan/gelatin bio-polymer (CGGV) film with good mechanics, water resistance, antioxidant and ultraviolet-proof property was prepared. The micro-structure, physical and functional properties of CGGV film were studied. Results showed that vanillin as a cross-linking agent provided a compact inner micro-structure through Schiff base and hydrogen bond interaction. Moderate cross-linking significantly improved mechanical strength, thermal ability, hydrophobicity of the films and reduced the water vapor permeability, swelling ratio and water solubility. Especially, CGGV films showed stronger ultraviolet-proof properties and possessed potent radical scavenging activity. Therefore, CGGV film is suitable to protect per-mature fruits and could be used as novel multifunctional packaging in the agriculture and foods industry.