The effect of surface adsorption of caffeic, chlorogenic, and gallic acids on the properties of cellulose- and nanocellulose-based films

Abstract

The study of plant waste-based composites as alternatives to plastic is significant due to their biodegradability and environmental impact. However, composites based on natural plant fibers still need improvement, particularly in terms of mechanical, hydrophobic, antioxidant, and antimicrobial properties. Bioactive compounds such as phenolic acids may enhance these properties. This study aims to elucidate the mechanisms and effects of polysaccharide films made from micro- and nanofibrillated cellulose derived from apple pomace, and the adsorption of phenolic acids (caffeic, chlorogenic, and gallic acids) on their surface. Molecular interactions affecting the surface, mechanical, antioxidant, and antimicrobial properties of the composites were investigated. Raman spectroscopy revealed spectral changes in C-O and C-OH bonds, which influenced the composites' surface wettability. Nanocellulose-based composites with caffeic acid exhibited the best packaging properties, including a homogeneous structure, increased stiffness, deformation resistance, and enhanced hydrophobicity. Composites with gallic acid showed the highest surface hydrophilicity and antioxidant capacity. Understanding these molecular interactions can aid in the further development of packaging materials