Durably Antibacterial Cotton Fabric Prepared by a Combination of Betaine and Carboxymethyl Chitosan

A simple pad-dry-cure modification process is proposed to prepare the antibacterial cotton fabrics with durable antibacterial properties. Two natural antibacterial materials, carboxymethyl chitosan (CMC) and betaine (Bet), were grafted on cotton fiber surface to achieve the goal. FTIR-ATR and XPS results reveal that esterification and amidation reactions have taken place between the CMC, Bet, and the cellulose chains on the surface of cotton fibers. Antibacterial evaluation results confirm the antibacterial capability and the durability of the modified fabrics. The bacterial reduction (BR) rates against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are higher than 99.99 % and can be kept at a level higher than 95 % even after 20 washing cycles. According to the XRD results presented, the entire modification process wreaks little damage to the crystalline structure of the cotton fabric. Especially, both the water vapor permeability and water absorption capability were improved (371.1 g/m2/d and 198 %, respectively) when compared to the original cotton fabric. This work provided a new way to fabricate antimicrobial cotton fabric using bio-based compounds, displaying great application potential in the antibacterial textile industry.