Estudo da inserção de nanopartículas de prata em tecido de poliéster durante a etapa de tingimento do tecido para acabamento antimicrobiano

Abstract

Smart textiles have gained prominence in the modern textile industry by incorporating nanomaterials capable of providing advanced functional properties. However, the direct incorporation of nanoparticles into textile fibers is costly and complex, while conventional finishing techniques often exhibit poor durability in nanoparticle fixation. To address this gap, the present study investigated an alternative approach: the in situ incorporation of silver nanoparticles (AgNPs) into polyester fabrics during the exhaust dyeing process. Three synthesis methodologies were developed and compared, all employing chitosan as a stabilizing agent. In one method, sodium borohydride was used as the reducing agent, whereas in the others, reduction was induced by water under controlled conditions. The nanoparticles were characterized using UV-Visible spectroscopy, dynamic light scattering (DLS), thermogravimetric analysis (TGA), scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS), and X-ray diffraction (XRD), both before and after lyophilization. The results indicated that lyophilization promoted greater particle size uniformity and enhanced antimicrobial activity. However, SEM and atomic absorption analyses revealed low incorporation of nanoparticles into the fabric. Although the dyed fabrics exhibited antimicrobial activity, it was not possible to attribute this effect solely to AgNPs, as both chitosan and sodium hydroxide used in the syntheses also possess intrinsic antimicrobial properties. It is concluded that dyeing-based functionalization with nanoparticles is a promising strategy for developing antimicrobial textiles, though further optimization is needed regarding synthesis conditions and nanoparticle–substrate interactions. Future work should include stability and wash resistance tests, as well as isolated evaluation of the individual synthesis components, to better elucidate the mechanisms responsible for the observed antimicrobial activity.