SCIENTIFIC BASIS OF SILVER NANOPARTICLES COATINGS FORMATION ON SURFACE OF POLYPROPYLENE ULTRATHIN FIBERS

New principles of silver nanoparticles coatings formation on the ultrathin fibers surface using electromagnetic radiation of the deci- and nanometer ranges for bactericidal modification of liquid media were proposed. Coating production involves the formation of silver nanoparticles as a result of photoreduction from an aqueous solution of AgNO3 with a concentration of 0.001M at the presence of ultrathin polypropylene fibers with their subsequent stabilization on the surface of the fibers with microwave radiation of the fiber material are initiated, which prevents agglomeration and stabilize silver nanoparticles on their surface. Ultrathin polypropylene fibers obtained as a result of pneumatic spraying of the melt are represented by an average diameter dav = 1.5-6 μm and a fairly wide lognormal distribution. The possibility of a two-step formation of coatings on the polymer fibers surface has been demonstrated using the method of numerical simulation of the self-assembly and self-organization of silver nanoparticles, taking into account the dissipation of their energy into the polymeric matrix through the exciton and phonon channels. It has been established that as a result of local microwave heating of silver nanoparticles, processes of the formation of supramolecular structures of the fiber material are initiated, which prevents agglomeration and stabilizes silver nanoparticles on their surface. The coatings obtained were characterized by transmission electron microscopy and spectroscopy. For example, silver nanoparticles formed and attached to the surface of fibers as a result of a ten-minute exposure to ultraviolet radiation have a size of 50 ± 18 nm. Studies of bactericidal activity showed that ultrathin polypropylene fibrous materials with coatings based on silver nanoparticles can effectively perform antibacterial treatment of natural waters with a high level of microbiological contamination. After 10 cycles of water purification, the amount of silver in the samples, according to atomic emission spectroscopy, remains unchanged.