Effects of silver nanoparticle on mechanical properties of polylactide composite yarns with different structure

In this work, composite mono- and multifilament yarns of polylactide (PLA) containing 1 wt.% of commercial Poviargol (silver nanoparticles stabilized with poly(vinylpyrrolidone)) were prepared. The results of scanning electron microscopy revealed that filler particles are uniformly distributed inside PLA yarns, irrespective of sample type. It was also shown that, during spinning of monofilament yarns, the filler did not emerge to the yarn surface, whereas the surfaces of multifilament yarns were virtually strewn with silver nanoparticles. The analysis of antibacterial response demonstrated that the Poviargol-containing multifilament yarns, unlike the monofilament yarns, possessed antibacterial activity against the standard Staphylococcus aureus strain (dilutions 1 × 10⁶ and 1 × 10⁷ CFU/mL). Differential scanning calorimetry showed that the presence of 1 wt.% of Poviargol did not exert any influence on thermal performance and phase transitions in PLA. Finally, it was confirmed that Poviargol did not affect mechanical properties of monofilaments, and although its presence caused a certain decrease in mechanical strength of multifilaments, this difference did not exceed 15%.