Effect of curcumin-modified nanodiamonds on properties of eco-friendly polylactic acid composite films

Polylactic acid (PLA) has attracted much attention as a biodegradable polymer material, but its inherent brittleness limits its application. In order to improve the overall performance of PLA, thermoplastic polyurethane (TPU) was first blended with PLA to improve the toughness, and then curcumin-functionalized nanodiamond (ND-Cur) was added to the polymer matrix to improve the strength and toughness of PLA. The effects of nanoparticles on the structure, thermal and mechanical properties of polymer matrix were investigated by scanning electron microscopy, thermogravimetric analysis and tensile testing. When the addition of ND-Cur is 1.5 wt%, the mechanical properties of the composite are the best, and the elongation at break is 124.8%, which is 119.9% higher than that of PLA. At this time, the improvement of thermal stability is also the most significant, and the T5% (temperature at 5% heat loss of sample) of the film is 47.9% higher than that of pure PLA. In addition, the modification also improved the hydrophobicity of the composite film.