THE CHELATING PROPERTIES OF CHITOSAN FIBERS

Chitosan fibers were treated with aqueous solutions of CuSO4 and ZnSO4 for different periods of time to prepare samples containing different levels of metal-ion contents. The effect of metal ions on the tensile properties of chitosan fibers was studied. It was found that after ch elation of metal ions the chitosan fibers gained substantial increases in both dry and wet strengths. The metal ions were readily removed fr om the chitosan fibers by treatment with an aqueous EDTA solution. The effect of the degree of acetylation on the chelating ability of the c hitosan fibers was also studied. It was found that after acetylation t he chitosan fibers lost the chelating ability due to the conversion of primary amine groups to acetamide groups.