Dyeing and characterization of cellulose nanofibers to improve color yields by dual padding method

The study of functional and dyeing properties of the electrospun nanofibers has recently gained substantial interest. However, the dyeing of nanofibers still in transition phase and faces problem of lower color yield. Owing to the higher surface area of cellulose nanofibers, the color yield obtained is nearly four to five times lower than the conventional cotton fiber. The present work reports on dyeing of cellulose nanofibers with CI reactive black 5 dye via a simple and dual padding method to improve color yield and dye fixation. The color yields were determined by K/S values and color coordinates using spectrophotometer and the results were compered between single and dual padding methods. The dyed cellulose nanofibers were characterized by FTIR, WAXD and FE-SEM. X-ray diffraction studies revealed that the dyed cellulose nanofibers having Cellulose II form and show a better crystallinity than the undyed cellulose nanofibers.