Modification of PA/PU superfine non-woven fiber for breath property using collagen and vegetable tannins

Unfigured sea-island superfine fiber PA/PU non-woven (USFSLB) is used to mimic leather's microstructure as the base of artificial leather. USFSLB has many characteristics and advantages resembling those of natural leather. However, compared with natural leather, the wearing comfort of artificial leather is inferior due to its poor moisture adsorption and permeability. In this work, a two-step method of chemical treatment is proposed, in which collagen/chromium-vegetable tannin (C-CrT) is immobilized on nylon fiber of USFSLB to improve its moisture adsorption and permeability (breath property). The two-step surface modification involved sulfuric acid hydrolysis and modifying the C-CrT on nylon fiber. Compared with the pristine USFSLB, the tensile strength, the elongation at break, the anti-static performance, the thickness, and the uniformity of C-CrT-treated USFSLB were improved at different levels. Importantly, the C-CrT-treated USFSLB showed excellent moisture adsorption and permeability, especially the liquid wicking rate (LWR) improved by 344%. The self-assembly mechanism of collagen/chromium-vegetable tannin (C-CrT) modified on nylon fibers was analyzed and discussed.