Electrospun TPU Nanofibers with Natural Dyes: Parameter Optimization and Properties Analysis

Thermoplastic polyurethane (TPU) nanofibers were successfully fabricated using natural dyes derived from turmeric and black tea via an electrospinning process, offering a sustainable and eco-friendly alternative to synthetic dyes. This study addresses the environmental and health concerns associated with synthetic dyes by systematically optimizing the dyeing process. We determined that 80 °C for 60 min is ideal for turmeric dye extraction, while 60 °C for 60 min yields the best results for black tea, achieving superior color yield and mechanical performance. The incorporation of natural dyes significantly enhanced the mechanical properties of the nanofibers, with turmeric-dyed nanofibers exhibiting a tensile strength of 31 MPa and strain elongation of 153.21% and black tea-dyed nanofibers achieving a tensile strength of 45 MPa and 99% strain elongation. The dyed nanofibers demonstrated excellent colorfastness to washing, rubbing, and light exposure as evaluated by the ISO 105-C10:2006 standard method, ensuring their durability in practical applications. Additionally, the nanofibers exhibited functional properties, including UV protection, antibacterial activity, and antioxidant effects, making them suitable for applications in protective clothing, filtration membranes, tissue engineering scaffolds, and drug delivery systems. This research highlights the dual advantages of natural dyes in improving both the mechanical performance and functional properties of TPU nanofibers. By replacing synthetic dyes with natural alternatives, this study offers a sustainable solution to reduce the environmental impact of textile production and supports their commercialization.