Triazine-Based Porous Organic Polymers with High CO2 Adsorption Capacity: Enhancing Flame Retardancy and Preventing Molten Dripping in Biobased Nylon 56

Biobased Nylon 56 is inherently flammable and prone to producing significant melt droplets during combustion, presenting substantial challenges for flame-retardant applications. Herein, we propose a novel and eco-friendly flame-retardant strategy for Nylon 56 by leveraging the high CO₂ adsorption capacity of triazine-based organic porous polymers. These triazine-based organic porous polymers (PTs), constructed within the fabric through a simple in situ polymerization process, form a robust protective barrier during combustion. They showed a good CO₂ adsorption capacity of 51.20 cm³ g^-1 at 273 K/1.0 bar, and the adsorbed CO₂ can act as a noncombustible gas, diluting flammable gases, lowering oxygen concentration, and reducing combustion temperature, thereby effectively suppressing flame propagation. Additionally, the porous structure enables the intertwining of polyamide chains in Nylon 56, enhancing the wash durability and long-term stability. Treated fabrics (NY-PT-1 and NY-PT-2) achieved a UL-94 V-0 rating, with limiting oxygen index (LOI) values increasing from 23% to 29.3% and 28%, respectively, while preventing molten dripping and maintaining excellent washing durability. This work demonstrates a sustainable and innovative approach to flame retardancy, combining CO₂ adsorption, thermal insulation, and char formation, offering a significant advancement in fire-safe textile development.