Enhancing properties of thermoplastic starch composite films with chitin nanofibers

Our study focuses on the extraction of chitin nanofibers (ChNFs) from shrimp shell waste using a combined deacetylation treatment and mechanical disintegration approach. The deacetylation process involving sodium hydroxide partially replaces acetamido groups within the chitin structure with amino groups, facilitating the disintegration of ChNFs. These disintegrated nanofibers were subsequently incorporated into thermoplastic starch (TPS). The incorporation of ChNFs into TPS resulted in a significant improvement in the mechanical properties, wettability, and barrier properties of the composites. This improvement was attributed to the better interfacial interaction between ChNFs and TPS associated with well-dispersed ChNFs within the matrix. Additionally, the starch-based composite films exhibited superior water resistance, compared to the neat TPS films. After immersion in distilled water for 12 h with vigorous stirring, the neat TPS film exhibited fragmentation, whereas the ChNF-reinforced TPS composites showed resistance to fragmentation. These findings highlight the potential of chitin nanofiber-reinforced composite films as sustainable packaging materials.