Durable antimicrobial cotton fabric fabricated by carboxymethyl chitosan and quaternary ammonium salts

In this article, carboxymethyl chitosan (CMC) and (3-carboxypropyl) trimethylammonium chloride (CPTC) were used as raw materials to prepare an antibacterial cotton fabric with excellent laundering durability. CMC was first anchored to the surface of cotton fiber via esterification between the carboxyl groups of CMC and the hydroxyl groups of the cellulose molecules on the cotton fiber surface, and then the CPTC was linked to the CMC chains via amidation to the amino groups of the grafted CMC chains. The antibacterial tests showed that the bacteriostatic reduction rate (BR) of the finished cotton fabric against S. aureus and E. coli was above 99.9%, and the BR value of modified cotton fabric remained above 99.9% even after 120 laundering cycles. The results of cytotoxicity, vapor transmissibility, and tensile strength of the fabric samples, as well as the evaluation of water absorption and flexibility show that the modified cotton fabrics are safe and comfortable.