Rheological, microstructural, thermal and barrier properties of polylactide/polyethylene glycol/inulin/encapsulated cinnamon essential oil films

The ongoing use of polymeric materials and associated pollution is a challenge to our society. It has resulted in a shift in the industry from polymeric to sustainable packaging. The aim of this work was to fabricate extruded polylactide (PLA)-based packaging by incorporating inulin, polyethylene glycol, and cinnamon essential oil encapsulates. The fabricated film samples were characterized by various analytical tools (rheometer, TGA, FTIR, XRD, and AFM) to gain deeper insights into their compatibility and the effect of microstructure evolution on film-forming properties for their potential packaging applications. Rheologically, the blend melt exhibited a shear-thinning behavior and improved the mechanical rigidity of plasticized PLA films upon incorporation of CEO encapsulates. The thermal stability of the films was validated by the TGA thermograms, and the analyzed films showed insignificant variations from one another. The smoothness of the PLA/PEG/CEOINL film, along with the presence of some inulin particles on the surface, was evident. The XRD and FTIR peaks suggest a loss of volatiles during extrusion. The barrier properties of the films did not enhance with the addition of encapsulates or inulin to PLA. Overall, the PLA/PEG/CEOINL film has potential for active food packaging in anticipation of its antimicrobial properties, as demonstrated in the encapsulates. Highlights: PLA/inulin/cinnamon essential oil active packaging films were fabricated. The addition of inulin lowered the mechanical and thermal properties of the film. The melt rheology of the films exhibited the shear-thinning behavior. Unlike inulin, CEO distributes well on the PLA composite films.