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Dyeing natural cellulose fibers from cornhusks / Narendra Reddy in Industrial & engineering chemistry research, Vol. 50 N° 9 (Mai 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 9 (Mai 2011) . - pp. 5642-5650 Titre : Dyeing natural cellulose fibers from cornhusks : a comparative study with cotton fibers Type de document : texte imprimé Auteurs : Narendra Reddy, Auteur ; Vigneshwar Arul Thillainayagam, Auteur ; Yiqi Yang, Auteur Année de publication : 2011 Article en page(s) : pp. 5642-5650 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Comparative  study Résumé : This research shows that natural cellulose fibers extracted from cornhusks have better dyeing properties for direct and sulfur dyes and similar dyeing properties for reactive and vat dyes compared to cotton fibers dyed under similar dyeing conditions. Cornhusk fibers have unique structure and properties compared to cotton and common lignocellulosic fibers. However, the short single cells, higher amounts of lignin and hemicellulose, lower percent crystallinity and relatively coarse fibers make the common cellulose fiber dyeing conditions unsuitable to dye cornhusk fibers. In this research, cornhusk fibers were dyed with one dye each from four dye classes, direct, reactive, vat, and sulfur dyes. The dyeing behavior of the fibers was fit in to the common isotherms and the kinetic parameters such as dyeing rate constant, diffusion coefficient, and half-time for dyeing were calculated. It was found that the physical properties of the fibers and structure of the dye had considerable influence on the dye sorption and rate of dyeing. Lower percent crystallinity, smaller crystal size, and presence of hemicellulose, lignin, and higher amounts of surface impurities are mostly responsible for the higher dye sorption on com fibers compared to cotton. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24128689 [article] Dyeing natural cellulose fibers from cornhusks : a comparative study with cotton fibers [texte imprimé] / Narendra Reddy, Auteur ; Vigneshwar Arul Thillainayagam, Auteur ; Yiqi Yang, Auteur . - 2011 . - pp. 5642-5650. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 9 (Mai 2011) . - pp. 5642-5650 Mots-clés : Comparative  study Résumé : This research shows that natural cellulose fibers extracted from cornhusks have better dyeing properties for direct and sulfur dyes and similar dyeing properties for reactive and vat dyes compared to cotton fibers dyed under similar dyeing conditions. Cornhusk fibers have unique structure and properties compared to cotton and common lignocellulosic fibers. However, the short single cells, higher amounts of lignin and hemicellulose, lower percent crystallinity and relatively coarse fibers make the common cellulose fiber dyeing conditions unsuitable to dye cornhusk fibers. In this research, cornhusk fibers were dyed with one dye each from four dye classes, direct, reactive, vat, and sulfur dyes. The dyeing behavior of the fibers was fit in to the common isotherms and the kinetic parameters such as dyeing rate constant, diffusion coefficient, and half-time for dyeing were calculated. It was found that the physical properties of the fibers and structure of the dye had considerable influence on the dye sorption and rate of dyeing. Lower percent crystallinity, smaller crystal size, and presence of hemicellulose, lignin, and higher amounts of surface impurities are mostly responsible for the higher dye sorption on com fibers compared to cotton. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24128689

Improving the resistance of sulfur dyes to oxidation / Wenlong Zhou in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4720–4725 Titre : Improving the resistance of sulfur dyes to oxidation Type de document : texte imprimé Auteurs : Wenlong Zhou, Auteur ; Yiqi Yang, Auteur Année de publication : 2010 Article en page(s) : pp. 4720–4725 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Sulfur  Oxidation Résumé : A method that substantially improves the oxidative bleaching resistance of sulfur dyed textiles is reported. Sulfur dyes are known for their poor bleaching resistance due to the sensitivity of the sulfur linkages to oxidation. This disadvantage severely prohibits the broad application of sulfur dyes because of the existence of the activated oxidative bleaching agents in many commercial detergents. In this study, 1% (w/w) of lanthanum triacetate was applied to sulfur dyed cotton fabrics via a simple padding procedure to chemically stabilize the sulfur linkages. The treatment could render sulfur dyed cotton fabrics a reduction in color changes of about 50% after laundering with detergent containing a bleaching agent, an improvement in strength retention of almost 100% after aging and an improvement in staining resistance of at least 0.5-class for about 1/3 of the sulfur dyes examined. These improvements were proved durable to repeated launderings. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901901r [article] Improving the resistance of sulfur dyes to oxidation [texte imprimé] / Wenlong Zhou, Auteur ; Yiqi Yang, Auteur . - 2010 . - pp. 4720–4725. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4720–4725 Mots-clés : Sulfur  Oxidation Résumé : A method that substantially improves the oxidative bleaching resistance of sulfur dyed textiles is reported. Sulfur dyes are known for their poor bleaching resistance due to the sensitivity of the sulfur linkages to oxidation. This disadvantage severely prohibits the broad application of sulfur dyes because of the existence of the activated oxidative bleaching agents in many commercial detergents. In this study, 1% (w/w) of lanthanum triacetate was applied to sulfur dyed cotton fabrics via a simple padding procedure to chemically stabilize the sulfur linkages. The treatment could render sulfur dyed cotton fabrics a reduction in color changes of about 50% after laundering with detergent containing a bleaching agent, an improvement in strength retention of almost 100% after aging and an improvement in staining resistance of at least 0.5-class for about 1/3 of the sulfur dyes examined. These improvements were proved durable to repeated launderings. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901901r

Low-temperature wet-cross-linking of silk with citric acid / Narendra Reddy in Industrial & engineering chemistry research, Vol. 50 N° 8 (Avril 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4458–4463 Titre : Low-temperature wet-cross-linking of silk with citric acid Type de document : texte imprimé Auteurs : Narendra Reddy, Auteur ; Karlin Warner, Auteur ; Yiqi Yang, Auteur Année de publication : 2011 Article en page(s) : pp. 4458–4463 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Silk  Citric  acid Résumé : We report the development of a novel method of improving the wet wrinkle recovery of silk fabrics without affecting the whiteness or the tensile properties of the cross-linked fabrics. Previous attempts on cross-linking silk with poly(carboxylic acids) have been done in the dry state at high temperatures (150−175 °C) in the presence of the toxic catalyst, sodium hypophosphite, with decrease in the whiteness and tensile properties of the cross-linked fabrics. In this research, citric acid (CA) was used to cross-link silk in the wet state at low temperatures using weak acidic to neutral pH as catalyst. The effect of cross-linking conditions on the wrinkle recovery, whiteness index and yarn tensile and fabric tear strength were studied. The durability of the cross-linking to laundering was also examined. The new method of cross-linking improves the wet wrinkle recovery of the silk fabrics by about 32% compared to the noncross-linked fabric without affecting the whiteness or the tensile properties of the fabrics. The improvement in the functional properties of silk was stable to multiple launderings. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie102226f [article] Low-temperature wet-cross-linking of silk with citric acid [texte imprimé] / Narendra Reddy, Auteur ; Karlin Warner, Auteur ; Yiqi Yang, Auteur . - 2011 . - pp. 4458–4463. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4458–4463 Mots-clés : Silk  Citric  acid Résumé : We report the development of a novel method of improving the wet wrinkle recovery of silk fabrics without affecting the whiteness or the tensile properties of the cross-linked fabrics. Previous attempts on cross-linking silk with poly(carboxylic acids) have been done in the dry state at high temperatures (150−175 °C) in the presence of the toxic catalyst, sodium hypophosphite, with decrease in the whiteness and tensile properties of the cross-linked fabrics. In this research, citric acid (CA) was used to cross-link silk in the wet state at low temperatures using weak acidic to neutral pH as catalyst. The effect of cross-linking conditions on the wrinkle recovery, whiteness index and yarn tensile and fabric tear strength were studied. The durability of the cross-linking to laundering was also examined. The new method of cross-linking improves the wet wrinkle recovery of the silk fabrics by about 32% compared to the noncross-linked fabric without affecting the whiteness or the tensile properties of the fabrics. The improvement in the functional properties of silk was stable to multiple launderings. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie102226f