Abstract. Modification of the fabric is one of the best routes to improve the affinity between dye and fabric. In this study, chemical modification of organic cotton fabric has been done by the greener way with the use of chitosan and nanochitosan. Chitosan is a kind of natural polysaccharide was prepared from crab shells. The prepared chitosan converted into nanochitosan by ultrasonification. Organic cotton is a variety which is grown and processed without using synthetic fertilizer and pesticides. The modification levels were measured by dyeing with two reactive dyes. The present work proved that considerable value of dye uptake was noticed in modified organic cotton using chitosan and nanochitosan. Due to the absorption of dyes by chitosan is mostly by electrostatic interactions and the larger surface area of chitosan nanoparticles. The above statements are proved by K/S values of dyed samples. By using XRD and debye scherrer’s formula we predict the crystal size of the chitosan nanoparticles. The differences in surface morphology of the ordinary chitosan and nano chitosan treated organic fabrics were confirmed by SEM analysis. AFM studies show the 2D and 3D form of nano chitosan particles.



Keywords: Chitosan, Nanochitosan, Modification, Organic cotton, Reactive dye.