Influence of Chemical Modification on Sorption and Mechanical Properties of Cotton Fibers Treated with Chitosan

In the case of conventional application of textiles, efficient and permanent fixation of chitosan is of major importance. Cotton fibers were differently pre-treated (alkali treatment, bleaching, demineralization) and then oxidized using differing procedures containing KIO4 solutions in order to discover which preparation procedure for cotton fibers is, from the viewpoint of mechanical and sorption properties, the most convenient for later treatments with chitosan. The results showed that all the oxidation procedures, even under very mild conditions, have a significant influence on the worsening of mechanical properties. The treatment of oxidized cotton with chitosan had no influence on breaking force and elongation, but increased Young's initial modulus of fibers. Chitosan adsorption also increased the moisture absorption of the fibers. Contact angles with water, however, depend on the average molecular weight of the chitosan used. Chitosan with lower molecular weight increased the hydrophilicity of the treated fibers, but chitosan with higher molecular weight, decreased it.