Dope-dyed polyurethane electrospun nanofibers

Electrospun polyurethane nanofibrous mats are used in stretchable, flexible, memory and other technical materials. Lately, their potential for aesthetic purposes has been explored, and various dyeing techniques, as an additional process, and the environmental impact have been reported. Herein, the dope dyeing technique of polyurethane electrospun nanofibers with disperse dyes is reported as a part of the electrospinning process. Dope dyeing when compared to other techniques consumes lesser time, reduced cost and environmental impact, and produces better color and uniformity. The preparation of dope solution, electrospinning and post dye curing processes was optimized for producing the colored polyurethane nanofibrous mat. Dope-dyed polyurethane nanofibrous mats produced good colored yield and colorfastness results. Moreover, the morphology of undyed and dyed polyurethane nanofibers was similar as observed in the SEM analysis and presence of the dye molecules were evident in the FTIR analysis.