Preparation of polyacrylonitrile-based fibres with chelated Ag ions for antibacterial applications

The need for an excellent antibacterial material that is sufficiently powerful to never develop bacterial resistance is urgent. In this study, a series of novel polyacrylonitrile-based fibres with chelated Ag ions (referred to as Ag-SH-PANF) were prepared by a two-step chemical modification process: grafting and chelating. The properties of the as-prepared Ag-SH-PANF were characterized by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The antibacterial activities of Ag-SH-PANF were examined against pathogenic bacteria, and an antibacterial mechanism was explicated based on the release of Ag ions from the fibres' surfaces. The results showed that, although chelation occurred between the Ag ions and the grafted amino, sulfhydryl and disulfide groups, Ag-SH-PANF retained its fine microstructure and thermal stability. Moreover, Ag-SH-PANF displayed excellent antibacterial ability against pathogenic bacteria as well as good washing durability. In terms of the antibacterial mechanism, Ag ions are the main bactericidal agents in the role of catalysts and are not consumed in the antibacterial process. Nonetheless, a relatively higher concentration of Ag ions can accelerate the bactericidal process.