Modified polyacrylonitrile nanofibers for improved dyeability using anionic dyes

Besides the functional properties of nanofibers, esthetic properties are also very significant for their applications and, thus, should be paid sufficient attention to. In the present article, the coloration of electrospun-modified polyacrylonitrile (PAN) nanofibers was investigated, where the PAN nanofibers were colored by anionic reactive dyes. To improve the dyeability, PAN was modified by introducing second and third monomer on the macromolecular chains using the free radical polymerization method. Then the modified PAN nanofibers were fabricated by electrospinning and dyed with reactive dyestuff, where the dyeing parameters such as temperature, time, pH and concentrations of the dyestuff were optimized. Compared to their unmodified counterparts, modified PAN nanofibers showed much better dye uptake and color fastness. Moreover, the morphology of nanofibers was not affected by the dyeing process, which is necessary for many critical applications of PAN nanofibers.