SI File.pdf

Biopolymers composed of polysaccharides are often used in various fields to either fully or partially replace synthetic polymers. Chitosan (CS), a linear polysaccharide, is mostly used in the field of packaging and medicine. The objective of this research was to investigate the feasibility of CS and poly(allylamine ‎hydrochloric acid) (PAH) blend films in terms of color, the presence of functional groups, ‎morphology, thermal stability, tensile strength (TS), and biodegradability for food packaging ‎applications. Four films namely, CPA-0 (100% CS), CPA-1 (90% CS/10% PAH), CPA-2 (80% CS/20% PAH), and CPA-3 (70% CS/30% PAH) were prepared and characterized. The films were characterized using UV/Vis, FT-IR, XRD, and DSC. The physical properties (grammage, thickness, density, and water solubility), optical properties (color and opacity), moisture barrier properties (WVTR and WVP), mechanical strength (% elongation, TS, and YM), thermal characteristics, and biodegradability were investigated to assess the potential of prepared films for their utilization in food packaging applications. It was observed that the film comprising 10% PAH (CPA-1) displayed relatively better mechanical properties, thermal stability, promising moisture barrier, biodegradability (100% within 14 days), and good color tones. CPA-1 exhibited maximum values of TS (83.62 MPa) and YM (2.9 GPa). UV/Visible spectroscopy showed that CPA-1 exhibited 80% transmittance in the visible region. DSC analysis indicated that CPA-1 exhibited an endothermic peak at a relatively high temperature of 130 °C, suggesting enhanced molecular stability of the CS matrix upon the addition of PAH. The results of the XRD analysis revealed a semi-crystalline structure featuring an orderly arrangement of the polymer, which was instrumental in imparting good mechanical properties. This study may pave the way for new possibilities in utilizing blend films as a viable option for food packaging.,