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Cross-linking cotton cellulose by the combination of maleic acid and sodium hypophosphite. 1. / Charles Q. Yang in Industrial & engineering chemistry research, Vol. 49 N° 18 (Septembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 18 (Septembre 2010) . - pp. 8325–8332 Titre : Cross-linking cotton cellulose by the combination of maleic acid and sodium hypophosphite. 1. : fabric wrinkle resistance Type de document : texte imprimé Auteurs : Charles Q. Yang, Auteur ; Dongzhong Chen, Auteur ; Jinping Guan, Auteur Année de publication : 2010 Article en page(s) : pp. 8325–8332 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hypophosphite  Acid Résumé : Durable press finishing agents used to produce wrinkle-resistant cotton garments are cross-linking agents for cotton cellulose. Polycarboxylic acids have been the promising durable press finishing agents to replace the formaldehyde-based reagents when sodium hypophosphite (NaH2PO2) was used as the catalyst. In our previous research, we found that a polycarboxylic acid esterifies cotton cellulose by first forming a five-membered cyclic anhydride as a reactive intermediate. Maleic acid (MA) is a bifunctional carboxylic acid, therefore is not able to form the second cyclic anhydride intermediate once it forms the first ester linkage with cotton. However, we discovered that MA imparted wrinkle resistance to cotton fabrics when NaH2PO2 was present, thus indicating that MA was able to cross-link cotton. Sodium hypophosphite functions as the catalyst for the esterification of cellulose by MA, and the esterification takes place at relatively low temperatures (≥130 °C). Esterification of MA forms single esterlinkage with cellulose and does not cross-link cotton cellulose. As the temperature increases ≥160 °C, NaH2PO2 starts to be bound to cotton. The data suggested that H−P−H of hypophosphite likely reacts with the >C═C< bonds of the two MA molecules already esterified with cellulose, thus forming a cross-linkage between two cellulose molecules. Even though this proposed cross-linking mechanism of MA on cotton is supported indirectly by the data presented here, direct experimental evidence are still needed to prove such a mechanism. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1007294 [article] Cross-linking cotton cellulose by the combination of maleic acid and sodium hypophosphite. 1. : fabric wrinkle resistance [texte imprimé] / Charles Q. Yang, Auteur ; Dongzhong Chen, Auteur ; Jinping Guan, Auteur . - 2010 . - pp. 8325–8332. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 18 (Septembre 2010) . - pp. 8325–8332 Mots-clés : Hypophosphite  Acid Résumé : Durable press finishing agents used to produce wrinkle-resistant cotton garments are cross-linking agents for cotton cellulose. Polycarboxylic acids have been the promising durable press finishing agents to replace the formaldehyde-based reagents when sodium hypophosphite (NaH2PO2) was used as the catalyst. In our previous research, we found that a polycarboxylic acid esterifies cotton cellulose by first forming a five-membered cyclic anhydride as a reactive intermediate. Maleic acid (MA) is a bifunctional carboxylic acid, therefore is not able to form the second cyclic anhydride intermediate once it forms the first ester linkage with cotton. However, we discovered that MA imparted wrinkle resistance to cotton fabrics when NaH2PO2 was present, thus indicating that MA was able to cross-link cotton. Sodium hypophosphite functions as the catalyst for the esterification of cellulose by MA, and the esterification takes place at relatively low temperatures (≥130 °C). Esterification of MA forms single esterlinkage with cellulose and does not cross-link cotton cellulose. As the temperature increases ≥160 °C, NaH2PO2 starts to be bound to cotton. The data suggested that H−P−H of hypophosphite likely reacts with the >C═C< bonds of the two MA molecules already esterified with cellulose, thus forming a cross-linkage between two cellulose molecules. Even though this proposed cross-linking mechanism of MA on cotton is supported indirectly by the data presented here, direct experimental evidence are still needed to prove such a mechanism. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1007294

Cross-linking cotton cellulose by the combination of maleic acid and sodium hypophosphite. 2. fabric fire performance / Charles Q. Yang in Industrial & engineering chemistry research, Vol. 50 N° 10 (Mai 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 5889-5897 Titre : Cross-linking cotton cellulose by the combination of maleic acid and sodium hypophosphite. 2. fabric fire performance Type de document : texte imprimé Auteurs : Charles Q. Yang, Auteur ; Qingliang He, Auteur ; Bojana Voncina, Auteur Année de publication : 2011 Article en page(s) : pp. 5889-5897 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Fires Résumé : Multifunctional carboxylic acids have been used as durable press finishing agents for cotton with sodium hypophosphite (NaH2PO2) as the most effective catalyst. In our previous research, we found that cellulose cross-linking takes place when cotton fabric treated with a combination of maleic acid and NaH2PO2 is cured at ≥150°C. The data suggested that H-P-H of hypophosphite likely reacts with >C=C< of the maleic acid already esterified with cotton cellulose, thus making it possible to form cross-linking on cotton. In this research, we studied the effect of the maleic acid (MA) and NaH2PO2 treatment on the fire performance of cotton using microscale combustion calorimetry. We found that esterification of cotton by MA reduces the flammability of the cotton cellulose. NaH2PO2 catalyzes the esterification ofMA on cotton, thus further reducing the cotton fabric's flammability by increasing esterification on cotton. The quantity of ester formed on cotton reaches the optimum range when the curing temperature is increased to ≥ 140 °C. When the curing temperature reaches ≥150°C, the reaction between NaR2PO2 and MA takes place on cotton. The bonding of hypophosphite to cotton further enhances the flame retardancy of the MA-treated cotton fabric as indicated by further decrease in heat release rate and further increase in char formation. The cotton fleece treated with the combination of maleic acid and NaH2PO2 at low concentrations is able to achieve class 1 flammability specified by 16 CFR 1610 at low concentrations. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158884 [article] Cross-linking cotton cellulose by the combination of maleic acid and sodium hypophosphite. 2. fabric fire performance [texte imprimé] / Charles Q. Yang, Auteur ; Qingliang He, Auteur ; Bojana Voncina, Auteur . - 2011 . - pp. 5889-5897. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 5889-5897 Mots-clés : Fires Résumé : Multifunctional carboxylic acids have been used as durable press finishing agents for cotton with sodium hypophosphite (NaH2PO2) as the most effective catalyst. In our previous research, we found that cellulose cross-linking takes place when cotton fabric treated with a combination of maleic acid and NaH2PO2 is cured at ≥150°C. The data suggested that H-P-H of hypophosphite likely reacts with >C=C< of the maleic acid already esterified with cotton cellulose, thus making it possible to form cross-linking on cotton. In this research, we studied the effect of the maleic acid (MA) and NaH2PO2 treatment on the fire performance of cotton using microscale combustion calorimetry. We found that esterification of cotton by MA reduces the flammability of the cotton cellulose. NaH2PO2 catalyzes the esterification ofMA on cotton, thus further reducing the cotton fabric's flammability by increasing esterification on cotton. The quantity of ester formed on cotton reaches the optimum range when the curing temperature is increased to ≥ 140 °C. When the curing temperature reaches ≥150°C, the reaction between NaR2PO2 and MA takes place on cotton. The bonding of hypophosphite to cotton further enhances the flame retardancy of the MA-treated cotton fabric as indicated by further decrease in heat release rate and further increase in char formation. The cotton fleece treated with the combination of maleic acid and NaH2PO2 at low concentrations is able to achieve class 1 flammability specified by 16 CFR 1610 at low concentrations. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158884

The Combination of itaconic acid and sodium hypophosphite as a new cross - linking system for cotton / Huitao Peng in Industrial & engineering chemistry research, Vol. 51 N° 35 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 35 (Septembre 2012) . - pp. 11301-11311 Titre : The Combination of itaconic acid and sodium hypophosphite as a new cross - linking system for cotton Type de document : texte imprimé Auteurs : Huitao Peng, Auteur ; Charles Q. Yang, Auteur ; Xilie Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 11301-11311 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Itaconic  acid Résumé : In this research, we studied cross-linking of cotton fabrics using the combination of itaconic acid (ITA) and sodium hypophosphite (NaH2PO2). ITA, a bifunctional carboxylic acid, was able to esterify cotton cellulose to form a single ester linkage, but it was not able to form cross-linking between two cellulose molecules. In the presence of NaH2PO2, the amount of ester formed on cotton fabric was increased substantially and the esterification temperature of ITA was reduced. Therefore, NaH2PO2 functioned as a catalyst for esterification of cotton by ITA. Moreover, we found that wrinkle resistance of the cotton fabric was significantly improved when cotton fabrics were treated with the combination of ITA and NaH2PO2.We also found that phosphorus was bound to the treated cotton fabric and that the increase in the wrinkle recovery angle of the treated fabric was correlated to the increase in the amount of phosphorus bound to cotton. All the data indicated that H–P–H of sodium hypophosphite probably reacts with the >C═C< of two ITA molecules, which are also esterified with cellulose, thus forming a cross-linkage between the two cellulose molecules. The cotton fabrics treated with the ITA/NaH2PO2 system demonstrated a high level of durable press performance with significantly lower tensile strength loss than those treated with the formaldehyde-based dimethyloldihydroxyethyleneurea. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3005644 [article] The Combination of itaconic acid and sodium hypophosphite as a new cross - linking system for cotton [texte imprimé] / Huitao Peng, Auteur ; Charles Q. Yang, Auteur ; Xilie Wang, Auteur . - 2012 . - pp. 11301-11311. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 35 (Septembre 2012) . - pp. 11301-11311 Mots-clés : Itaconic  acid Résumé : In this research, we studied cross-linking of cotton fabrics using the combination of itaconic acid (ITA) and sodium hypophosphite (NaH2PO2). ITA, a bifunctional carboxylic acid, was able to esterify cotton cellulose to form a single ester linkage, but it was not able to form cross-linking between two cellulose molecules. In the presence of NaH2PO2, the amount of ester formed on cotton fabric was increased substantially and the esterification temperature of ITA was reduced. Therefore, NaH2PO2 functioned as a catalyst for esterification of cotton by ITA. Moreover, we found that wrinkle resistance of the cotton fabric was significantly improved when cotton fabrics were treated with the combination of ITA and NaH2PO2.We also found that phosphorus was bound to the treated cotton fabric and that the increase in the wrinkle recovery angle of the treated fabric was correlated to the increase in the amount of phosphorus bound to cotton. All the data indicated that H–P–H of sodium hypophosphite probably reacts with the >C═C< of two ITA molecules, which are also esterified with cellulose, thus forming a cross-linkage between the two cellulose molecules. The cotton fabrics treated with the ITA/NaH2PO2 system demonstrated a high level of durable press performance with significantly lower tensile strength loss than those treated with the formaldehyde-based dimethyloldihydroxyethyleneurea. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3005644