Impact of Cu‐ <scp> TiO ₂ </scp> Nanocomposite on the Physical, Mechanical, and Antimicrobial Properties of Polylactic Acid/Thermoplastic Starch Films

ABSTRACT Extensive research is being carried out on the development of biodegradable packaging films. Antimicrobial activity is one among the critical factors in food packaging. In the present work, Cu‐TiO 2 nanocomposite has been synthesized by the reduction of copper ions using L‐ascorbic acid in the presence of TiO 2 nanoparticles. Formation of copper nanoparticles has been confirmed by x‐ray diffraction, and morphology has been observed by scanning electron microscopy. Nanocomposite has been compounded with poly lactic acid (PLA) and thermoplastic starch (TPS) using a twin‐screw extruder, followed by the blowing of films. The prepared film has tensile strength and elongation of 31.11 ± 0.93 MPa and 2.83% ± 0.12%, respectively. The obtained values are similar to PLA/TPS film with TiO 2 . Cu‐TiO 2 nanocomposite film has ~80%–85% transparency in the visible region. Antimicrobial activity against E. coli and S. aureus has been observed for the Cu‐TiO 2 nanocomposite film, with about an order of magnitude lower colony‐forming unit as compared to the film with TiO 2 . Weight loss of 4.4% has been observed for the film buried in composting medium for 30 days.