Papers by Author: Feng Yan Li

Abstract: Enzymes including starch-degrading enzymes and glucose oxidase are used in one-bath process to desize and bleach cotton fabrics. The effect of enzyme concentration on pretreatment efficiency, especially bleaching of cotton fabrics has been investigated by innovatively focusing on glucose conversion ratio of desizing products. The results showed that the starch sizing materials of cotton fabrics were completely removed by starch-degrading enzymes. The conversion ratio of glucose in desized liquor increased with concentration of glucoamylase. Consequently, whiteness of cotton fabrics bleached in one-bath process was also improved, and an increase of 7% in whiteness of bleached fabrics was observed. The fabric tear strength was decreased. However, the loss ratio could be controlled below 15%. The properties of softness and adsorption of bleached cotton fabrics were satisfactory.

Abstract: Electrically conductive fabrics were prepared with interlacing polyester yarns and wrapped yarn of polyester/NiCr filament. The wrapped yarns are lined in different distance along filling direction, and the effect of distance on electrically conductivity of fabrics with plain weave is analyzed. In addition, wearing properties including fabric thickness and air permeability of such fabrics are also tested. The results show that surface charge density decrease with number increase of wrapped yarns in filling direction. When wrapped yarns are arranged at 3 yarns/ 6 cm for twill weave, the fabric density and air permeability increase with fabric density.

Abstract: The 80Ni20Cr coatings on cotton fabric substrates using the electron beam evaporated deposition are reported to improve the electrical conductivity of fabric substrates. The cotton fabrics are coated twice for single-faced NiCr film and one time per face for double-faced NiCr film, respectively. The morphology of coatings is characterized by an optical microscopy. The effect of sample length and test orientation of warp-wise and weft-wise on electrical conductivity is measured. It is found that the NiCr coatings dramatically increase the electrical conductivity of cotton fabrics. For warp-wise orientation with lengthwidth (4 cm1 cm) of test sample, the surface resistance is about 0.7 MΩ for single-faced coating and 0.89 MΩ for double-faced coating, while the surface resistance of raw cotton fabric is above 104 MΩ. The results tested from warp-wise and weft-wise are uniform, which is mainly because of the structure balance of the plain fabrics. The microstructure observation indicates that the single-faced coatings are uniform and dense, and the present double-faced coating processes are not enough to completely cover the fabric substrates. The uniform and dense coatings of single-faced NiCr coatings could be the reason that the electrical conductivity is better than that of the present double-faced NiCr coating.