Sugarcane bagasse-derived xanthan gum improves polyvinyl alcohol films for food packaging

Abstract

Introduction: The increasing demand for environmentally responsible packaging materials has intensified the search for renewable alternatives to conventional fossil-based plastics. Among the available options, biodegradable polymers show great potential, although their mechanical performance and barrier properties still require improvement for broader industrial use. Materials and methods: In this study, films based on polyvinyl alcohol (PVA) and xanthan gum (XG), including two xanthan gum variants produced from sugarcane bagasse (XGL1 and XGL2), were prepared by the solventcasting method and evaluated through mechanical, thermal, morphological, spectroscopic, and water vapor barrier analyses. Results: The incorporation of xanthan gum positively affected film performance, particularly for the PVA/XGL1 formulation. This film showed a 37.9% increase in tensile strength compared with pure PVA, an elongation at break of 270.97%, lower water vapor permeability (0.243 g·mm/m2·h·kPa), and a higher contact angle (80.81°), indicating reduced sensitivity to moisture. Fourier transform infrared spectroscopy (FTIR) results suggested strong intermolecular interactions between PVA and xanthan gum, while Field emission gun scanning electron microscopy (FEG-SEM) analysis revealed homogeneous and compact structures. Conclusions: Although the films remained moderately water-soluble and thermal degradation began near 200 °C, the overall performance obtained demonstrates the potential of the PVA/XGL1 blend for food packaging applications. In addition to improving material properties, the use of xanthan gum produced from sugarcane bagasse provides a productive route for valorizing agro-industrial residues, contributing to the development of sustainable packaging materials with reduced environmental impact.