Manufacture and performance of O-carboxymethyl chitosan sodium salt/cellulose fibers in N-methylmorpholine-N-oxide system

A series of O-carboxymethyl chitosan sodium salt (NaCMCh) with different degree of substitution (DS) of -CH₂COONa agent were successfully prepared by altering the reaction temperature and time. Both fourier transform infrared spectroscopy (FTIR) and ¹³C-Nuclear Magnetic Resonance (¹³C-NMR) were used to study the structure of NaCMCh. And the impact of DS on the antibacterial activity of NaCMCh was investigated. Then, the NaCMCh with optimal antibacterial activity was selected to prepare NaCMCh/cellulose fibers in N-methylmorpholine-N-oxide (NMMO) system. The structure, crystallization behavior, thermal property and morphology of obtained fibers were carefully studied with FTIR, Wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermal gravimetric (TG) and scanning electron microscope (SEM), respectively. Meanwhile, the antibacterial activity as well as mechanical properties of resultant fibers was also investigated. The results demonstrated that the fibers had strong antibacterial activity against Escherichia coli (E. coli), acceptable mechanical properties and good water retention.