Comprehensive Characterization of Enhanced Performance PLA/TiO2 Packaging Films Synthesized Via Ultrasonication Assisted Solution Casting Process

This study aims to fabricate poly (lactic acid)/titanium dioxide (PLA/TiO₂) nano composite films for food packaging applications by using ultrasonication-assisted solvent casting approach. Conventional solvent-casting techniques often suffer from TiO₂ particle agglomeration leading to limited functional properties improvements. The proposed method combines ethanol pre-treatment of TiO₂ nanoparticles with prolonged ultrasonication followed by solvent casting. This method ensures uniform nanoparticle dispersion within the PLA matrix. Significant morphological, structural and functional improvements in properties is observed which includes shifts in carbonyl bands indicated in Fourier Transform Infrared Spectroscopy (FTIR), pronounced anatase peaks in X-ray diffraction (XRD). Further, water vapor permeability and water solubility was reduced to 43.5% and 50% respectively. Also, mechanical properties of PLA namely as tensile strength and Young’s modulus are increased by 24% and 160%, respectively. Additionally, TiO₂ acts as a strong nucleating agent, enhancing crystallinity and thermal stability, simultaneously hindering the growth of Staphylococcus aureus and Escherichia coli bacteria significantly. Cytotoxicity assessments realised composites’ biocompatibility with L929 fibroblast cells. Overall, this work presents a novel strategy to enhance uniform dispersion of nanoparticles for high-performance, antimicrobial, and thermally stable PLA/TiO₂ nano composite films, paving the way for next-generation biodegradable food packaging solutions.