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Effect of surfactants on iridescence developed by swollen lamellar phase of C12-alkenylsuccinic acid / Sudipta G. Dastidar in Industrial & engineering chemistry research, Vol. 48 N° 19 (Octobre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 19 (Octobre 2009) . - pp. 8856–8864 Titre : Effect of surfactants on iridescence developed by swollen lamellar phase of C12-alkenylsuccinic acid Type de document : texte imprimé Auteurs : Sudipta G. Dastidar, Auteur ; Bharath P., Auteur ; Antara Pal, Auteur Année de publication : 2009 Article en page(s) : pp. 8856–8864 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : C12-alkenylsuccinic  acid  Ionic  surfactants  Nonionic  surfactant  Cationic  surfactantSmall  angle  X-ray  scattering Résumé : The iridescence phenomenon of C12-alkenylsuccinic acid (ASA) is a result of the coherent reflection of light from periodically ordered alternating lamellar surfactant stacks and solvent molecules. Here we report the effect of cationic, anionic, and nonionic surfactants on the iridescence of ASA. It was observed that ionic surfactants resulted in destabilization of the iridescence of ASA, while the addition of nonionic surfactant stabilized the system. The nature of the interactions of these surfactants on ASA was investigated using reflectance spectroscopy, differential scanning calorimetry, optical microscopy, and small angle X-ray scattering (SAXS). The bilayer thickness was determined using reflectance spectra, SAXS, and theoretical calculations. It was observed that the nonionic surfactant does not alter the lamellar spacing of ASA, while ionic surfactant was seen to lower it by creating water-filled defects. The diffraction patterns also exhibit an additional broad peak which indicates formation of uncorrelated bilayers. This study thus provides understanding of such swollen lamellar systems. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie802011w [article] Effect of surfactants on iridescence developed by swollen lamellar phase of C12-alkenylsuccinic acid [texte imprimé] / Sudipta G. Dastidar, Auteur ; Bharath P., Auteur ; Antara Pal, Auteur . - 2009 . - pp. 8856–8864. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 19 (Octobre 2009) . - pp. 8856–8864 Mots-clés : C12-alkenylsuccinic  acid  Ionic  surfactants  Nonionic  surfactant  Cationic  surfactantSmall  angle  X-ray  scattering Résumé : The iridescence phenomenon of C12-alkenylsuccinic acid (ASA) is a result of the coherent reflection of light from periodically ordered alternating lamellar surfactant stacks and solvent molecules. Here we report the effect of cationic, anionic, and nonionic surfactants on the iridescence of ASA. It was observed that ionic surfactants resulted in destabilization of the iridescence of ASA, while the addition of nonionic surfactant stabilized the system. The nature of the interactions of these surfactants on ASA was investigated using reflectance spectroscopy, differential scanning calorimetry, optical microscopy, and small angle X-ray scattering (SAXS). The bilayer thickness was determined using reflectance spectra, SAXS, and theoretical calculations. It was observed that the nonionic surfactant does not alter the lamellar spacing of ASA, while ionic surfactant was seen to lower it by creating water-filled defects. The diffraction patterns also exhibit an additional broad peak which indicates formation of uncorrelated bilayers. This study thus provides understanding of such swollen lamellar systems. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie802011w