Sustainable Water-Resistant Cotton Fabrics Coated with a Chitosan/Wax Composite Extracted from Discarded Outer Cabbage Leaves

The water-resistant properties of a chitosan/OCL wax composite were evaluated on cotton fabrics using a dip-coating method. The plant-based wax was extracted from discarded outer cabbage leaves. The influence of the chitosan-to-OCL wax weight ratio on textile properties—including wettability, air permeability, mechanical performance, and stiffness—was systematically investigated. In addition, laundering tests were conducted to assess the durability of the coating. The results demonstrated that the cotton fabric coated with a chitosan/OCL wax composite at a 70/30 weight ratio exhibited the highest hydrophobicity, achieving a water contact angle of 157.87°. The coated cotton fabrics also showed good washing stability. Measurements of bending length and flexural rigidity revealed that cotton fabrics coated with the chitosan/OCL wax composite exhibited greater stiffness than the untreated samples. The combined use of chitosan and OCL wax provided a synergistic enhancement in water-resistant performance. These findings highlight the potential of the chitosan/OCL wax composite as a non-toxic and environmentally friendly finishing agent for cotton fabrics.