The Influence of Biodegradable Dispersed Fillers Obtained by Spray Drying on the Mechanical Properties of Polylactide Fibers

Composite fibers based on a polylactide (PLA) matrix with the addition of dispersed spherical particles, namely chitin nanoparticles modified with polyethylene glygol (PEG) and silver nanoparticles modified with polyvinylpyrrolidone, have been obtained using a twin-screw microextruder. The resulting fibers were subjected to high-temperature orientational drawing four and six times. The features of the mechanical properties and supramolecular structure of oriented composite fibers have been studied. The similar character of the curves of the tensile diagrams of PLA fibers and composite fibers based on it is shown. A gradual increase in the strength of composite fibers elongated by a factor of four with an increase in the concentration of spherical particles has been established. In the case of fiber drawing by a factor of six, the maximum strength is observed by an average of 20% at a concentration of silver nanoparticles of 1 wt %, and chitin nanoparticles 5 wt %. The values of deformation and elastic modulus of composite fibers remain close to those of unfilled PLA fibers. It has been found that composite fibers have a highly oriented fibrillar structure. Good adhesion of the PLA matrix to the surface of PEG-modified chitin particles has been shown.