Structural, Thermal, Optical, Mechanical, and Antibacterial Properties of PLA/Nanoclay/TiO2 Nanocomposite Films

In this report, Polylactide/Nanoclay/TiO2 nanocomposite films with two different weight percentages (2wt% and 5wt %) of clay and TiO2 nanoparticles were prepared by a cost-effective approach. A solvent casting process with the help of a cost-effective film applicator was used to prepare nanocomposite films. The surface morphology investigations revealed the agglomeration of fillers at higher weight percentages and uniform mixing of fillers at lower weight percentages. The crystallinity of the prepared films did not alter much with the nanofiller addition. Nanofillers with a 2wt% concentration in the PLA matrix enhanced thermal and mechanical properties significantly. The PLA nanocomposite films have exhibited an intense broad emission band in violet color with a wavelength of ≈420 nm. In addition, the antibacterial activity of polylactic acid nanocomposite films was investigated against Gram-positive S. aureus and Gram-negative E. coli bacteria. The enhanced antibacterial activity is observed for a 5wt% concentration of nanofillers. The results showed that the antibacterial activity increases with nanofiller concentration. This study presents a simple and cost-effective approach to preparing nanocomposite films with tuneable properties of mechanical, thermal, and antibacterial activity.