Fabrication of antimicrobial and high-toughness poly (lactic acid) composite films using tung oil derivatives

Int J Biol Macromol. 2024 Jan;254(Pt 1):127792. doi: 10.1016/j.ijbiomac.2023.127792. Epub 2023 Nov 1.

Abstract

Tung oil derivatives are promising alternatives to traditional toxic plasticizers for improving the toughness of poly (lactic acid) (PLA) films. In this study, a tung oil-based quaternary ammonium salt (Q-ETO) was synthesized using a multi-step process involving epoxidation, ring opening, and substitution reactions. PLA based composite films with various amounts of Q-ETO were prepared by solvent casting. The impact of various amount of Q-ETO on PLA/Q-ETO composite films were evaluated with regard to their mechanical properties, hydrophilicity, water vapor permeability, optical properties, thermal stability, antibacterial properties, and leaching properties. The PLA/5%Q-ETO composite film yielded the highest elongation at break (82.52 ± 9.53 %), which was 153.67 % higher than that of pure PLA. All PLA composite films showed an antibacterial efficiency exceeding 90 % against both S. aureus and E. coli. Moreover, the PLA/Q-ETO composite film blocked the transmission of both ultraviolet and visible light while preventing the permeation of water vapor. The addition of Q-ETO only weakly affected the color and thermal stability of the PLA/Q-ETO composite film. Given the numerous advantages of the PLA composite film, it has significant potential for application as a food packaging material.

Keywords: Antibacterial efficiency; High-toughness; Poly (lactic acid); Tung oil derivative.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Anti-Infective Agents*
  • Escherichia coli*
  • Food Packaging
  • Lactic Acid
  • Polyesters
  • Staphylococcus aureus
  • Steam

Substances

  • tung oil
  • Steam
  • Anti-Infective Agents
  • Anti-Bacterial Agents
  • Polyesters
  • Lactic Acid