Development of Cross-linked Chitosan Films Reinforced with Chitin Nanofibers

The growing demand for sustainable alternatives to petroleum-based polymer materials has driven the development of bio-based materials. Among them, chitosan stands out as a promising biopolymer due to its biodegradability and biocompatibility. However, its hydrophilicity, causing high water absorption, limits its practical applications. In this study, tannic acid was employed as a cross-linking agent, and chitin nanofibers (ChNFs) were introduced as a reinforcing agent to enhance the properties of the chitosan-based films. The incorporation of ChNFs significantly improved the tensile stress of the films without compromising their transparency. Furthermore, the cross-linked chitosan films with ChNFs exhibited excellent UV-blocking capabilities. This highlights their potential as an alternative to conventional petroleum-based polymers.