PARTIAL REDUCTION OF WOOL FABRICS WITH THIOGLYCOLIC ACID IN CONCENTRATED AQUEOUS SOLUTION OF SODIUM CHLORIDE

Autor: Koh-Ichi Kajiyama, Yasumasa Sato, Munenori Sakamoto
Rok vydání: 1977
Předmět:
Zdroj: Sen'i Gakkaishi. 33:T307-T313
ISSN: 1884-2259
0037-9875
DOI: 10.2115/fiber.33.7_t307
Popis: Wool fabrics were partially reduced with thioglycolic acid (TGA) in the aqueous solution of NaCl of different concentration followed by S-cyanoethylation with acrylonitrile (AN) under the conditions sufficient for the complete S-cyanoethylation of cysteine residues in reduced wool. The gas-liquid chromatographic amino acid analysis of the reduced and cyanoethylated wool fabrics indicated that the extent of the reduction with TGA decreased remarkably with increase in the concentration of NaCl of the reducing bath. Thus, the reduction with 0.5M TGA at 40°C for 30 min yielded 154μ moles/g of S-cyanoethylcysteine residues, while the reduction with 0.5M TGA in the saturated aqueous solution of NaCl at the same temperature for the same duration yielded only 34μ moles/g, both after the treatment with AN. The MIR infrared spectra of the sample A (prepared by partial reduction in the saturated aqueous solution of NaCl followed by the treatment with AN) and the sample B (prepared by complete reduction with tri-n-butylphosphine followed by the treatment with AN) showed the v C≡N absorption peak of about the same absorbance, suggesting that the surface layer of wool fibers was preferentially reduced in the saturated aqueous solution of NaCl. Abrasion resistance and hand of the fabrics were unchanged by reduction in the saturated aqueous solution of NaCl and the treatment with AN. The sample A did not exhibit the expected antifelting property. The sample B exhibited decreased felting shrinkage, however, with much decreased abrasion resistance. Yellowing took place during reduction and the treatment with AN. The yellowed fabrics were bleached by irradiation (carbon arc) for 10 h.
Databáze: OpenAIRE