Effects of carboxymethyl cellulose fiber formations with chitosan incorporation via coating and mixing processes

To date, the utilization of carboxymethyl cellulose (CMC) fibers are only restricted to weak mechanical application such as wound dressing. Physically, CMC has a weak mechanical strength due to the high hydrophilicity trait. However, this flaw was saved by the extensive number of reactive functional groups, allowing this macromolecule to form linkages with chitosan to ensure its versatility. This work successfully fabricated CMC-chitosan fiber via dissolution, crosslinking, dry-jet wet-spinning extrusion, and coagulation processes. Chitosan was constituted with CMC fiber in two approaches, coating, and inclusion at various concentrations. Morphologically, chitosan incorporation has triggered agglomerations and roughness toward CMC fibers (CMCF). Chemically, the interaction between CMC and chitosan was proved through FTIR analysis at peaks 1245 cm^-1 (ECH covalent crosslinking), while 3340 cm^-1 and 1586 cm^-1 were due to ionic and hydrogen bonding. The result from analysis showed that at higher chitosan concentrations, the chitosan-included CMC fiber (CMCF-I) and chitosan-coated CMC fiber (CMFC) were mechanically enhanced (up to 86.77 and 82.72 MPa), thermally more stable (33 % residual mass), and less hydrophilic compared to the plain CMCF. The properties of CMC-chitosan fibers have opened up vast possible applications, especially as a reinforcement in a watery medium such as a hydrogel.