Durably and intrinsically antibacterial polyamide 6(PA6)via backbone end-capping with high temperature-resistant imidazolium

The antibacterial polyamide 6(PA6)material has attracted great research interest due to its wide ap-plication in food packaging,biomedical fields,functional textiles,and other fields.However,it is still a challenge to prepare intrinsically antibacterial PA6 with highly efficient and durably antibacterial activity via polymerization.Herein,the antibacterial imidazolium ionic liquid of 3-carboxymethyl-1-decyl imida-zole chloride was designed and synthesized for adapting the polymerization and processing temperature of PA6.Then antibacterial PA6(PA6-IL)was synthesized through hydrolyzed ring-opening copolymeriza-tion with imidazolium at the end of the backbones.Compared to physical blending or post-modification methods,antibacterial agents as end-capping reagents of polymer backbones endowed PA6 with intrin-sic antibacterial activity.As expected,the obtained PA6-IL exhibited not just comparable physicochemical and mechanical properties to conventional PA6 but excellent antibacterial activity of low antibacterial time to 60 min and durability for 28 days.Additionally,the corresponding electrospun PA6-IL nanofi-brous membranes showed homogenous morphology and remarkable hydrophilicity of 7.7° as well as the high-efficient antibacterial activity.Melt-spun PA6-IL microfibers revealed a smooth surface as well as enhanced tensile strength and increased breaking elongation compared to those of conventional PA6.The PA6-IL microfibers also behaved with excellent antibacterial efficiency and durability.Accordingly,this work provides a feasible and straightforward strategy to prepare durably and intrinsically antibacterial PA6 materials especially PA6 fibers,which can be widely applied in the textiles field.