Design and Characterization of High-Performance SiO₂-WO₃-PLA Bio nanocomposites: Integrating Computational Modeling with Experimental Techniques for Next-Generation Food Packaging Thin Films

In this study, polylactic acid (PLA), in conjunction with polyethylene glycol (PEG), was utilized as the primary matrix, while green-synthesized silica (SiO₂) derived from rice husk and tungsten oxide (WO₃) were systematically incorporated into the composite formulation. A series of thin-film preparations were meticulously developed with varying SiO₂-WO₃ loadings (1%, 3%, 5%, 7%, and 10%) to assess their physicochemical enhancements. A comprehensive characterization regime was undertaken to elucidate the structural, morphological, thermal, and optical attributes of the fabricated thin films. X-ray diffraction (XRD) analysis confirmed the successful phase incorporation, exhibiting intensified crystallinity and congruence with pre-existing literature. Field emission scanning electron microscopy (FESEM) provided insights into the surface topology and homogeneity of the composite, while energy-dispersive X-ray spectroscopy (EDX) validated the elemental dispersion and compositional fidelity of the materials. Fourier transform infrared spectroscopy (FTIR) substantiated the molecular interactions and functional group retention within the PLA matrix. Furthermore, differential scanning calorimetry (DSC) delineated the thermal transitions and phase stability, whereas thermogravimetric analysis (TGA) revealed the degradation kinetics and thermostability of the synthesized bio composites. UV-visible (UV-Vis) spectroscopy facilitated the optical characterization, evaluating both transmittance and absorption properties, which were found to be highly promising for biodegradable packaging applications. Additionally, X-ray photoelectron spectroscopy (XPS) provided deeper insights into the electronic states and surface chemical composition of the composite materials. Mechanical properties, including tensile strength and elongation at break, were rigorously analyzed, revealing significant improvements with increasing silica and tungsten oxide loadings. Moreover, oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) assessments indicated superior barrier characteristics, crucial for food packaging applications. The resultant biodegradable thin films exhibited remarkable potential in sustainable material science, holding profound implications for the future of eco-friendly packaging solutions and advanced biopolymer-based engineering. The antimicrobial efficacy of the synthesized PLA-PEG-SiO₂-WO₃ composite thin films was rigorously evaluated through comprehensive antimicrobial assays. The assessment encompassed a broad-spectrum analysis against Gram-positive and Gram-negative bacterial strains, demonstrating significant bactericidal and bacteriostatic activities. The zone of inhibition (ZOI) studies, in conjunction with colony-forming unit (CFU) reduction assays, confirmed the antimicrobial potency, further corroborating the material’s suitability for food packaging and biomedical applications. The antimicrobial characterization results were systematically integrated into the abstract, emphasizing the composite's potential in pathogen-resistant biodegradable film development.