High antibacterial durability of silver nanoparticles anchored on cotton fiber surfaces by 4-vinylpyridine polymers synthesized via a “grafting through” strategy

This study aims at developing novel methodology to prepare antibacterial cotton fabric with excellent antibacterial durability, and a “grafting through” approach was adopted to enhance affinity of Ag NPs with cotton fiber surfaces. The surface modification was carried out by covalently linking acrylic acid (AA) molecules onto the fibers, then 4-vinylpyridine was copolymerized with the AA moieties as a polymeric binder. Once the coordination bonds were formed between silver nanoparticles (Ag NPs) and the pyridine nitrogen, Ag NPs could be stably immobilized on the cotton fabric. Experimental results showed that the AA-co-PVP grafting copolymer had a significant regulatory effect on the dispersion and particle size of Ag particles, and the resulting cotton fabric presented a high antibacterial property with excellent durability. Even after 120 washing cycles, the bacterial reduction rates of the modified fabric against both Staphylococcus aureus and Escherichia coli retained a level higher than 99%. In addition, other textile attributes, such as vapor transmissibility, water absorbability and flexibility, could be largely retained in the modified fabrics.