One-Step Zwitterionic Modification of Polyamide–Polyurethane Mixed Textile through Acidic Catalyzation

In this study, a straightforward one-step zwitterionic surface modification technique was developed for polyamide materials and fiber products, providing excellent antibiofouling properties. The surface of polyamide (PA) and polyurethane (PU) was modified using an epoxy-type biomimetic zwitterionic copolymer, poly(glycidyl methacrylate-<i>co</i>-sulfobetaine acrylamide) (PGSA), composed of glycidyl methacrylate and sulfobetaine acrylamide through an acidic-catalyzed one-step dip-coating method. Under acidic conditions, the molecular chains of polyamide were activated, exposing terminal amine groups that facilitated reactivity, enabling the epoxy-type zwitterionic copolymer to undergo ring-opening addition reactions. The optimization of coating parameters, including reaction temperature, solid concentration, copolymer molar ratio, and pH conditions, was conducted to achieve optimal antibiofouling performance. The modified polyamide fabric demonstrated enhanced biocompatibility and antibiofouling capabilities, including a 70% reduction of fibrinogen adsorption, a 93% reduction of whole-blood cell attachment, a 95% reduction of red blood cell attachment, and a 98.2% reduction of bacterial attachment. This simple and cost-effective zwitterionic modification technology for polyamide and polyurethane surfaces holds significant potential for biomedical device modification and functional textile applications.