The Characterization of Corn Starch Films Reinforced by Cellulose Nanocrystals Obtained From Collard Stems

Collard stems are considered waste materials containing high amounts of cellulose. The cellulose contained in collard stems was obtained with a yield of 28.59%. In this study, cellulose nanocrystals were produced using the extracted cellulose. FT‐IR spectra revealed that the bond structures of extracted cellulose and nanocellulose were not different from those of commercial cellulose. Zeta potential results indicated that particles had moderate stability, and the average diameter of the nanoparticles in solution was 506.3 nm. Biodegradable films were produced using corn starch (5%) with different CNC concentrations (1%, 2%, 3%, and 5%). The mechanical, barrier, and physicochemical properties of the films were investigated. Among the films, 5% CNC had the highest opacity. Moreover, the addition of 5% CNC provided the highest tensile strength. However, no significant effect was observed on water solubility and water vapor permeability. SEM images of the films revealed that the CNC filler was successfully embedded in the film. According to the TGA results, the addition of CNC resulted in a higher residual weight. Consequently, CNC is a promising filler material for biodegradable food packaging.