Evaluation of ultrasonic probe and bath sonication methods for the dispersion of TiO ₂ nanoparticles in PLA-based nanocomposites

Polylactic acid (PLA) is a promising biodegradable polymer that has someday, valuable applications in many industries. Its inherent brittleness and limited thermal stability, however, are restricting its wider use. In this study, titanium dioxide (TiO 2 ) nanoparticles were added to PLA films to enhance their mechanical and thermal properties. The two different methods of dispersing the nanoparticles, ultrasonic-probe sonication (UPS) and bath sonication (BS), were investigated for their effectiveness to achieve homogeneous nanoparticle distribution. The findings revealed improvement in mechanical and thermal properties of PLA/TiO 2 nanocomposites using both methods. UPS outperformed in achieving better dispersion, which led to measurably enhanced material properties. However, BS proved to be a valid and economically feasible method, producing composites with substantially improved properties compared to pure PLA, making it suitable for large-scale applications. Results indicated that the two approaches could thus be effectively utilized in creating high-performance nanocomposites from PLA intended for environmentally friendly biodegradable packaging, biomedical materials, or structural components requiring improved property performance.