Preparation and Anti-Bacterial Properties of Chitosan/Nano-Ag Modified Carboxymethyl Cellulose for Wound Dressing Materials

Aim at developing high-performance wound dressing with super moisture control performance, excellent antimicrobial activity, good biocompatibility as well as reduced cost, carboxymethyl rayon viscose yarns (CM-RVYs) had been successfully prepared by alkalinization and etherification of rayon viscose yarns using sodium hydroxide and chloroacetic acid. The antibacterial CM-RVYs were obtained by uniting chitosan/nano-Ag to the CM-RVYs through electrostatic interaction of the polyelectrolyte. The FTIR and XRD analysis showed that the rayon viscose yarns underwent different degrees of carboxymethylation with the change of the degree of substitution (DS). The change of DS could affect the water absorption, water retention, mechanical properties and antimicrobial properties of CM-RVYs, which in turn could determine their performance as antimicrobial and moisture control dressing. The research results indicated that with the increasing DS, crystallinity degree of CM-RVYs decreased gradually. The surface and cross section of modified rayon viscose yarns became rough and irregular along with various white crystal-like protuberances appeared on its surface. And water absorption and water retention of CM-RVYs both rose a lot, but its breaking strength first increased then decreased compared with breaking elongation fluctuated just between 16%. With DS of 0.51, the water absorption of CM-RVYs reached 13.01 g·g-1 and its breaking strength and breaking elongation were respectively at 8.54 cN and 15.27%. And chitosan/nano-Ag modified CM-RVYs showed good antibacterial properties against E. coli and S. aureus which would be used as high performance antibacterial and moisture control dressing.