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Aggregation of hydrophobic substituents of poly(acrylate)s and their competitive complexation by β- and γ-cyclodextrins and their linked dimers in aqueous solution / Jie Wang in Industrial & engineering chemistry research, Vol. 50 N° 12 (Juin 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 12 (Juin 2011) . - pp. 7566–7571 Titre : Aggregation of hydrophobic substituents of poly(acrylate)s and their competitive complexation by β- and γ-cyclodextrins and their linked dimers in aqueous solution Type de document : texte imprimé Auteurs : Jie Wang, Auteur ; Li, Li, Auteur ; Xuhong Guo, Auteur Année de publication : 2011 Article en page(s) : pp. 7566–7571 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Hydrophobic  substituents  Aqueous  solution Résumé : Competition between the aggregation of the octadecyl substituents of 3% randomly substituted poly(acrylate), PAAC18, and of the dodecyl substituents of the PAAC12 analogue, and their complexation by β-cyclodextrin, βCD, the linked dimers, N,N′-bis(6A-deoxy-6A-β-cyclodextrin)urea, 66βCD2ur, and N,N′-bis(6A-deoxy-6A-β-cyclodextrin)succinamide, 66βCD2su, and γ-cyclodextrin, γCD, and the analogous dimers 66γCD2ur and 66γCD2su have been studied in aqueous solution. The zero-shear viscosities of 3.3 wt % aqueous solutions of PAAC18, decreases in the presence of βCD, 66βCD2ur, 66βCD2su and γCD, is little changed in the presence of 66γCD2ur, and increases in the presence of 66γCD2su. In contrast, the zero-shear viscosities of aqueous solutions of PAAC12 increase in the presence of βCD, γCD, and their dimers but they are much less than those of the corresponding PAAC18 solutions. These macroscopic variations are due to host–guest complexation of the octadecyl and dodecyl substituents by βCD, γCD, and their dimers (as shown by 2D 1H NOESY NMR spectroscopy) competing with aggregation of the octadecyl and dodecyl substituents where differences in substituent length and cyclodextrin annular size are dominant factors. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101705e [article] Aggregation of hydrophobic substituents of poly(acrylate)s and their competitive complexation by β- and γ-cyclodextrins and their linked dimers in aqueous solution [texte imprimé] / Jie Wang, Auteur ; Li, Li, Auteur ; Xuhong Guo, Auteur . - 2011 . - pp. 7566–7571. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 12 (Juin 2011) . - pp. 7566–7571 Mots-clés : Hydrophobic  substituents  Aqueous  solution Résumé : Competition between the aggregation of the octadecyl substituents of 3% randomly substituted poly(acrylate), PAAC18, and of the dodecyl substituents of the PAAC12 analogue, and their complexation by β-cyclodextrin, βCD, the linked dimers, N,N′-bis(6A-deoxy-6A-β-cyclodextrin)urea, 66βCD2ur, and N,N′-bis(6A-deoxy-6A-β-cyclodextrin)succinamide, 66βCD2su, and γ-cyclodextrin, γCD, and the analogous dimers 66γCD2ur and 66γCD2su have been studied in aqueous solution. The zero-shear viscosities of 3.3 wt % aqueous solutions of PAAC18, decreases in the presence of βCD, 66βCD2ur, 66βCD2su and γCD, is little changed in the presence of 66γCD2ur, and increases in the presence of 66γCD2su. In contrast, the zero-shear viscosities of aqueous solutions of PAAC12 increase in the presence of βCD, γCD, and their dimers but they are much less than those of the corresponding PAAC18 solutions. These macroscopic variations are due to host–guest complexation of the octadecyl and dodecyl substituents by βCD, γCD, and their dimers (as shown by 2D 1H NOESY NMR spectroscopy) competing with aggregation of the octadecyl and dodecyl substituents where differences in substituent length and cyclodextrin annular size are dominant factors. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101705e

Polymeric networks assembled by adamantyl and β-cyclodextrin substituted poly(acrylate)s / Wang, Jie in Industrial & engineering chemistry research, Vol. 49 N° 2 (Janvier 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 2 (Janvier 2010) . - pp 609–612 Titre : Polymeric networks assembled by adamantyl and β-cyclodextrin substituted poly(acrylate)s : host−guest interactions, and the effects of ionic strength and extent of substitution Type de document : texte imprimé Auteurs : Wang, Jie, Auteur ; Pham, Duc-Truc, Auteur ; Xuhong Guo, Auteur Année de publication : 2010 Article en page(s) : pp 609–612 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Polymer  networks  Cyclodextrine  Acrylate  Ionic  strength. Résumé : The construction of polymer networks through host−guest complexation between the β-cyclodextrin (βCD) substituents of 6A-(1-(2-aminoethyl)amino)-6A-deoxy-β-cyclodextrin 2, 3, and 6% randomly substituted poly(acrylate) (PAAβCDen) and the adamantyl (AD) substituents of 1-(2-aminoethyl)amidoadamantyl 2, 3, and 6% randomly substituted poly(acrylate) (PAAADen) is reported. A 2D 1H NOESY NMR spectroscopic study shows the formation of host−guest complexes by the βCD and AD substituents. This is characterized by a complexation constant, K1 = 3020 ± 60 mol−1 dm3, for 3% substituted PAAβCDen and PAAADen as shown by isothermal titration calorimetry. The viscosity of a 2 wt % equimolar mixture of 3% randomly substituted PAAβCDen and PAAADen reaches a maximum at [NaCl] = 0.1 mol dm−3, and the viscosity and the storage and loss moduli (G′ and G′′) increase with the increase in degree of substitution from 2 to 6%. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901178q [article] Polymeric networks assembled by adamantyl and β-cyclodextrin substituted poly(acrylate)s : host−guest interactions, and the effects of ionic strength and extent of substitution [texte imprimé] / Wang, Jie, Auteur ; Pham, Duc-Truc, Auteur ; Xuhong Guo, Auteur . - 2010 . - pp 609–612. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 2 (Janvier 2010) . - pp 609–612 Mots-clés : Polymer  networks  Cyclodextrine  Acrylate  Ionic  strength. Résumé : The construction of polymer networks through host−guest complexation between the β-cyclodextrin (βCD) substituents of 6A-(1-(2-aminoethyl)amino)-6A-deoxy-β-cyclodextrin 2, 3, and 6% randomly substituted poly(acrylate) (PAAβCDen) and the adamantyl (AD) substituents of 1-(2-aminoethyl)amidoadamantyl 2, 3, and 6% randomly substituted poly(acrylate) (PAAADen) is reported. A 2D 1H NOESY NMR spectroscopic study shows the formation of host−guest complexes by the βCD and AD substituents. This is characterized by a complexation constant, K1 = 3020 ± 60 mol−1 dm3, for 3% substituted PAAβCDen and PAAADen as shown by isothermal titration calorimetry. The viscosity of a 2 wt % equimolar mixture of 3% randomly substituted PAAβCDen and PAAADen reaches a maximum at [NaCl] = 0.1 mol dm−3, and the viscosity and the storage and loss moduli (G′ and G′′) increase with the increase in degree of substitution from 2 to 6%. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901178q

Preparation of nickel nanoparticles in spherical polyelectrolyte brush nanoreactor and their catalytic activity / Zhongming Zhu in Industrial & engineering chemistry research, Vol. 50 N° 24 (Décembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13848-13853 Titre : Preparation of nickel nanoparticles in spherical polyelectrolyte brush nanoreactor and their catalytic activity Type de document : texte imprimé Auteurs : Zhongming Zhu, Auteur ; Xuhong Guo, Auteur ; Shuang Wu, Auteur Année de publication : 2012 Article en page(s) : pp. 13848-13853 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Catalyst  activity  Polyelectrolyte  Nanoparticle  Preparation Résumé : Nickel nanoparticles (Ni-NPs) with controlled size and narrow size distribution were successfully prepared in spherical poly (acrylic acid) (PAA) brushes (SPBs). The brushes act as nanoreactors for generating the Ni-NPs via adsorption of nickel ions in the brushes and subsequent reduction by addition of NaBH4. The size of Ni-NPs can be well-controlled in several nanometers and with narrow size-distribution. Most interestingly, the size can be tuned by the reaction temperature: the average size increased from 3 to 7 nm upon increasing the reaction temperature from 273 to 303 K. The catalytic activity of these Ni-NPs trapped in SPBs were evaluated using a model reaction based on the reduction of 4-nitrophenol to 4-aminophenol by NaBH4. The kinetic data were observed to follow the pseudofirst-order rate law, and the apparent rate constant was linearly dependent on the total surface area of the Ni-NPs and the reaction temperatures. This work opens a new way to prepare well-controlled Ni-NPs which should be ideal candidates for catalysts with high performance. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25299850 [article] Preparation of nickel nanoparticles in spherical polyelectrolyte brush nanoreactor and their catalytic activity [texte imprimé] / Zhongming Zhu, Auteur ; Xuhong Guo, Auteur ; Shuang Wu, Auteur . - 2012 . - pp. 13848-13853. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13848-13853 Mots-clés : Catalyst  activity  Polyelectrolyte  Nanoparticle  Preparation Résumé : Nickel nanoparticles (Ni-NPs) with controlled size and narrow size distribution were successfully prepared in spherical poly (acrylic acid) (PAA) brushes (SPBs). The brushes act as nanoreactors for generating the Ni-NPs via adsorption of nickel ions in the brushes and subsequent reduction by addition of NaBH4. The size of Ni-NPs can be well-controlled in several nanometers and with narrow size-distribution. Most interestingly, the size can be tuned by the reaction temperature: the average size increased from 3 to 7 nm upon increasing the reaction temperature from 273 to 303 K. The catalytic activity of these Ni-NPs trapped in SPBs were evaluated using a model reaction based on the reduction of 4-nitrophenol to 4-aminophenol by NaBH4. The kinetic data were observed to follow the pseudofirst-order rate law, and the apparent rate constant was linearly dependent on the total surface area of the Ni-NPs and the reaction temperatures. This work opens a new way to prepare well-controlled Ni-NPs which should be ideal candidates for catalysts with high performance. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25299850

Recoverable platinum nanocatalysts immobilized on magnetic spherical polyelectrolyte brushes / Shuang Wu in Industrial & engineering chemistry research, Vol. 51 N° 15 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 15 (Avril 2012) . - pp. 5608-5614 Titre : Recoverable platinum nanocatalysts immobilized on magnetic spherical polyelectrolyte brushes Type de document : texte imprimé Auteurs : Shuang Wu, Auteur ; Julian Kaiser, Auteur ; Xuhong Guo, Auteur Année de publication : 2012 Article en page(s) : pp. 5608-5614 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Polyelectrolyte Résumé : Recoverable platinum nanocatalysts immobilized on magnetic spherical polyelectrolyte brushes (MSPB) were synthesized and characterized by high resolution transmission electron microscope (HRTEM), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). High catalytic activity was found by photometrically monitoring the reduction of 4-nitrophenol by NaBH4 in the presence of MSPB-Pt composites. An excellent stability and recyclability of catalyst was observed after consecutive eight runs following by external magnetic-separation and redispersion. This novel approach provides an excited potential application in preparation of recyclable metal nanocatalysts with high activity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25815841 [article] Recoverable platinum nanocatalysts immobilized on magnetic spherical polyelectrolyte brushes [texte imprimé] / Shuang Wu, Auteur ; Julian Kaiser, Auteur ; Xuhong Guo, Auteur . - 2012 . - pp. 5608-5614. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 15 (Avril 2012) . - pp. 5608-5614 Mots-clés : Polyelectrolyte Résumé : Recoverable platinum nanocatalysts immobilized on magnetic spherical polyelectrolyte brushes (MSPB) were synthesized and characterized by high resolution transmission electron microscope (HRTEM), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). High catalytic activity was found by photometrically monitoring the reduction of 4-nitrophenol by NaBH4 in the presence of MSPB-Pt composites. An excellent stability and recyclability of catalyst was observed after consecutive eight runs following by external magnetic-separation and redispersion. This novel approach provides an excited potential application in preparation of recyclable metal nanocatalysts with high activity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25815841