Preparation and properties of 2-(2-aminoethoxy) ethyl chitosan/cellulose fiber using N-methylmorpholine-N-oxide process

N-methylmorpholine-N-oxide (NMMO) is used widely in the manufacturing of man-made cellulose fibers and functional lyocell fibers due to its environment-friendly advantage. Although chitosan is known as a natural antibacterial polymer it has poor solubility in neutral to basic medium and the antibacterial activity is shown only in acidic medium. Chitosan’s poor solubility in NMMO is the disadvantage for the production of antibacterial lyocell fibers. This paper investigates a more “NMMO soluble” derivative of chitosan, 2-(2-aminoethoxy) ethyl chitosan (AECS). AECS has greatly improved solubility in NMMO hydrate, and stronger antibacterial activity than chitosan. AECS was introduced to modify the lyocell fiber spun in a co-solution of cellulose and AECS in NMMO hydrate. The physical properties and antibacterial activity of the fibers were examined and the results indicated that the modified lyocell fiber, containing more than 2 wt% of AECS, exhibits good antibacterial activity against E. coli and slightly decreased tensile strength compared with unmodified fibers.