WET SPINNING OF CHITOSAN AND THE ACETYLATION OF CHITOSAN FIBERS

Chitosan fibers were made by wet spinning of its solution in 2% aqueou s acetic acid. The fiber properties were affected by processing condit ions, such as spin stretch ratio, coagulation bath composition, and dr ying conditions. The chitosan fibers were acetylated with acetic anhyd ride in methanol, producing regenerated chitin fibers. The acetylation process was affected by the reaction temperature, the treatment time, and the molar ratio of anhydride to amine groups. The properties of t he acetylated chitosan fibers were studied in terms of thermal stabili ty, solubility, and mechanical properties. It was found that, after ac etylation, the fibers had an improved thermal stability and tensile st rength. (C) 1993 John Wiley & Sons, Inc.