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Innovative, gemini-type molecular defoamer technology for improved coating aesthetics / Ernie C. Galgoci in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 3, N° 1 (01/2006)
[article]
Titre : Innovative, gemini-type molecular defoamer technology for improved coating aesthetics Type de document : texte imprimé Auteurs : Ernie C. Galgoci, Auteur ; Steven Y. Chan, Auteur ; Khalil Yacoub, Auteur Année de publication : 2006 Article en page(s) : p. 77-85 Note générale : Bibliogr. Langues : Américain (ame) Tags : Agent surface gemini Etude expérimentale Relation formulation propriété Démoussage Evaluation performance Diol Composé acétylénique non ionique Antimoussant Additif Peinture eau Matériau revêtement Index. décimale : 667.9 Revêtements et enduits Résumé : The use of conventional surfactants and defoamers in waterbome coatings can often create an undesirable cycle, whereby each imparts a negative effect that requires the other to solve. Molecular defoamers represent a novelclass of defoamers that break foam on a molecular level, which is unlike conventional defoamers that utilize macroscopic physical incompatibility within a coating formulation. This is accomplished by the ability of the molecular defoamer to adsorb at the air-water interface of a foam bubble and, thereby, displace some of the surfactants that stabilize the foam. Based on a fundamental understanding of the effects of basic adsorption parameters, innovative nonsilicone molecular defoamers were developed that provide long-term foam control, effectively reduce both surface tension and foam in a variety of emulsion polymers, and decrease significantly the level of defects in waterbome coating applications. A synergistic performance benefit was obtained when these molecular defoamers were used in combination in an acrylic, industrial maintenance formulation. DOI : 10.1007/s11998-006-0008-3 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-006-0008-3.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3723
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 3, N° 1 (01/2006) . - p. 77-85[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 003762 - Périodique Bibliothèque principale Documentaires Disponible Bis (diquaternary ammonium)salts : synthesis, effect of spacer on surface activities and aggregation properties of reactive red 198 in aqueous – surfactants solutions / Fatma H. Abdel-Salam in TENSIDE, SURFACTANTS, DETERGENTS, Vol. 48, N° 3/2011 (05/2011)
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Titre : Bis (diquaternary ammonium)salts : synthesis, effect of spacer on surface activities and aggregation properties of reactive red 198 in aqueous – surfactants solutions Type de document : texte imprimé Auteurs : Fatma H. Abdel-Salam, Auteur ; A. G. El-Said, Auteur Année de publication : 2011 Article en page(s) : p. 239-248 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Ammoniums quaternaires
Chimie des surfaces
Colorants réactifs
Précipitation (chimie)
SurfactantsTags : Synthèse 'Surfactants gémini cationiques' 'Propriétés surface' Aggrégation 'Comportement pigment réactif rouge 198' (RR 198) Index. décimale : 668.1 Agents tensioactifs : savons, détergents Résumé : A series of bis-diquaternary ammonium salts (cationic Gemini surfactants) with different length in spacer were prepared and characterized. The surface properties such as the critical micelle concentration CMC, minimum surface tension γCMC, effectiveness of the surface tension reduction πCMC, maximum surface excess Γmax and surface area per molecule Amin have been determined by means of surface tension measurements. As expected, these surfactants have good surface activities than those conventional monomeric ones (dodecyl trimethyl ammonium chloride (DTAC)) and the spacer plays an important role in the surface properties. Under experimental conditions, surface parameters decreases with the increase of carbon number of the spacer the except analogue with a benzene ring due to its inflexibility. The aggregation ability of some practically used reactive azodyes (C. I. Reactive Red 198) in aqueous solutions and the prepared surfactants was investigated using UV-visible spectroscopic methods. The spectroscopic studies were extended in order to determine the effect of molecular structure of the surfactants on the aggregative properties of C. I. Reactive Red 198 (RR 198). The aggregation behaviour of the RR 198 in solutions and in the presence of additives is related to their apparent deviations from Beer’s law and aggregation number (N). The aggregation constant (Kn) of the monomer/dimer equilibrium was calculated. The aggregate structures and the nature of the interacting pairs in this dye were discussed using Kasha exciton theory. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Methods - Synthesis - Measurements.
- RESULTS AND DISCUSSION : Structure characterization - Critical micelle concentration (CMC) - Adsorption on the air/solution interface - Aggregation of RR 198 under different concentration in aqueous solution - Aggregative properties of RR 198 dye in aqueous-surfactant solution - Molecular excitation of dimer structure of RR 198.Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=11706
in TENSIDE, SURFACTANTS, DETERGENTS > Vol. 48, N° 3/2011 (05/2011) . - p. 239-248[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 012974 - Périodique Bibliothèque principale Documentaires Disponible Development of cleavable surfactants / D. Shukla in TENSIDE, SURFACTANTS, DETERGENTS, Vol. 47, N° 1/2010 (01-02/2010)
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Titre : Development of cleavable surfactants Type de document : texte imprimé Auteurs : D. Shukla, Auteur ; V. K. Tyagi, Auteur Année de publication : 2010 Article en page(s) : p. 7-12 Note générale : Bibliogr. Langues : Anglais (eng) Tags : Cleavable surfactants Biodegradation Chemodegradable Hydrolyzable Gemini Diels-Alder reaction Index. décimale : 668.1 Agents tensioactifs : savons, détergents Résumé : Cleavable surfactants are of great interest for numerous reasons. These are amphiphiles in which a weak linkage has been deliberately inserted, normally, but not always, between the hydrophobic tail and the polar head group. Surfactant may degrade by chemical means, e.g., induced by acid, alkali, ultraviolet (UV) light, heat, or ozone. Acid- and alkali-labile surfactants have also attracted the attention in recent years. The main purpose for development of novel cleavable surfactants is to improve the biodegradation characteristics and the rate of biodegradation has consequently been studied for several of the surfactants. Alkali labile linkages that have been used for the purpose include normal ester bonds, betaine esters, and carbonates. This review deals the development of monomeric and gemini type cleavable surfactants. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8063
in TENSIDE, SURFACTANTS, DETERGENTS > Vol. 47, N° 1/2010 (01-02/2010) . - p. 7-12[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 011905 - Périodique Bibliothèque principale Documentaires Disponible Synthesis of 1,3-Bis-[(Dodecanoyl Oxypropyl Dimethylammonium) Propane] Dibromide Ester-Quat Surfactant: Micellar, Thermodynamic and Corrosion-Inhibiting Properties / S. Alehyen in TENSIDE, SURFACTANTS, DETERGENTS, Vol. 44, N° 3/2007 (06-07/2007)
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Titre : Synthesis of 1,3-Bis-[(Dodecanoyl Oxypropyl Dimethylammonium) Propane] Dibromide Ester-Quat Surfactant: Micellar, Thermodynamic and Corrosion-Inhibiting Properties Type de document : texte imprimé Auteurs : S. Alehyen, Auteur ; F. Benssejjay, Auteur ; M. El Achouri, Auteur ; M. R. Infante, Auteur ; L. Perez, Auteur ; Y. Benssouda, Auteur Année de publication : 2007 Article en page(s) : p. 160-167 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Anticorrosifs
Micelles
Surfactants
Tension superficielleTags : Gemini surfactant Bis-ester-quat Critical micellar concentration Surface tension corrosion inhibitor Index. décimale : 668.1 Agents tensioactifs : savons, détergents Résumé : Ester–quat surfactant: 1,3-bis-[(dodecanoyl oxypropyl dimethylammonium) propane] dibromide referred as 12-3-3-3-12 was synthesized, purified and characterized by Elemental Analysis, 1H-NMR, 13C-NMR, IR and Mass Spectra. The thermodynamic properties of aqueous solutions of this ester-quat were investigated using Electrical Conductivity and SurfaceTension measurements. The corresponding parameters of micellisation were determined for each technique. Otherwise the inhibitive action of the ester-quat (12-3-3-3-12) on the corrosion behaviour of iron was investigated in HCl and H2SO4 medium by means Electrochemical Resistance and Polarisation methods. The ester-quat 12-3-3-3-12 acts as a cathodic-type inhibitor. The maximum inhibition efficiency was reached around the critical micellar concentration. The ester-quat appears to be adsorbed in the metal/liquid interface through the general mode following the Frumkin adsorption model. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3216
in TENSIDE, SURFACTANTS, DETERGENTS > Vol. 44, N° 3/2007 (06-07/2007) . - p. 160-167[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 007660 - Périodique Bibliothèque principale Documentaires Disponible