Transfer Law and Influence of Water Molecules in Cotton Fabric After Liquid-Ammonia Treatment

Cotton, as a rich cellulose polysaccharide material in nature, has increasing applications. This work studies the transfer law of water in cotton fabric after liquid-ammonia treatment. The morphological and structural changes in cotton fabric, after liquid-ammonia treatment, are analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. The relationships between the gaseous and liquid water-transfer performances and the fiber morphology and structure are studied. Cotton fiber swells after liquid-ammonia treatment, and its surface becomes relatively smooth with increasing treatment time. The fiber changes from a twisted bent shape to a cylindrical shape, with a slight increase in luster. The chemical structure of cotton fiber treated with liquid ammonia does not show significant changes; however, its crystallinity decreases. After liquid-ammonia treatment, the breaking strength of cotton fabric increases and the elongation at break decreases; the K/S value of the dyed fabric increases, while the L^* value decreases accordingly. In addition, the breathability and moisture permeability increase. The wicking height first increases and then decreases, whereas the water retention gradually decreases. Using the entropy-weight–TOPSIS method, the water-transfer performance of cotton fabric treated with liquid ammonia at different times is comprehensively evaluated. The advantages and disadvantages of the treatment are ranked, to objectively and comprehensively analyze their rationality and theoretical significance. This work provides a new evaluation basis for the comprehensive analysis and evaluation of the moisture-transfer and moisture-comfort performance of cotton fabric.

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