Starch–PVA Bio‐Composite Films: Structural, Antimicrobial, and Biodegradation Studies for Sustainable Packaging

Abstract This study shows fully biodegradable starch‐polyvinyl alcohol (PVA) composite films formed via solvent casting as long‐term alternatives to synthetic packaging. The impact of starch concentration (0.0050–0.0125 M) on structural, functional, and environmental aspects was thoroughly assessed utilizing molecular modeling and material characterization techniques. Ultrasonic treatment enhanced polymer compatibility, leading to higher binding energies (−2.6 to −4.92 kcal/mol) at higher starch concentrations. The optimized films demonstrated excellent thermal stability, uniform morphology (FESEM), and controlled swelling (3.02–15.86%). The composites had strong antimicrobial activity against Staphylococcus aureus , Bacillus cereus (Gram‐positive), Klebsiella pneumoniae (Gram‐negative), and fungi ( Aspergillus fumigatus, A. niger) , with binding energies of −4.27 to −5.19 kcal/mol (bacteria) and −6.59 to −7.31 kcal/mol (fungi). Notably, soil burial studies revealed rapid biodegradation, with film degrading in just 21 days, 3.2 times faster than traditional PVA. These starch‐PVA biocomposites stand out as viable alternatives for environmentally friendly food packaging due to their strong antibacterial efficacy and rapid breakdown. The findings offer vital insights into sustainable polymer design, emphasizing the structure‐property‐degradation linkages that are critical for next‐generation green materials. This approach provides a practical solution to reduce plastic pollution while maintaining functional performance.