Rapid and quantitative determination of critical micelle concentration by automatic continuous mixing and static light scattering

cited By 29International audienceWe present the rapid and quantitative characterization of ionic, non-ionic and zwitterionic surfactants based upon the combination of an automatic continuous mixing technique and static light scattering. Collection and subsequent analysis of data are both rapid and semiautomatic, which increases precision, sensitivity, and range of applicability while substantially decreasing the amount of manual intervention required by the investigator. By treating the continuous data, the entire data set may be rapidly analyzed in the context of the closed association model to determine the critical micelle concentration cmc and aggregation number Nag of a detergent; these technique are comparable in the scope and resolution currently obtainable from other conductimetric, fluorescence and surface tension techniques. © 2009

Thermogelation of methylcellulose: rheological considerations

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Hydrophobically modified associating polyacrylamide (HAPAM) synthesized by micellar copolymerization at high monomer concentration

cited By 57International audienceA series of hydrophobically modified polyacrylamides and their hydrolyzed derivatives containing both long hydrophobic groups C18 (<1.2 mol%), and carboxylic groups (20 mol%) have been prepared by micellar polymerization at high monomer concentration (19 wt%) and post-hydrolysis. 1H and 13C NMR elucidation of polymer microstructures displayed a good agreement with feed ratio. Post-hydrolysis process seems to be a more effective route to control the hydrolysis degree. Physico-chemical parameters determination by automatic continuous mixing (ACM) techniques in dilute solution shows the effect of the blocky distribution on the reinforcement of intramolecular hydrophobic association. Rheological measurements show potential thickening properties according to sticky reptation model. © 2007 Elsevier Ltd. All rights reserved

Wood protective fungicidal treatment: Quaternary ammonium molecules grafting on cellulose assisted by afterglows at atmospheric pressure

International audienceWood or cellulosic materials protection against fungi is possible by binding covalent molecules as quaternary ammonium compounds (QAC) on the hydroxyl reactive groups present in cellulose. This work firstly consists in the synthesis of a specific quaternary ammonium molecule containing a long aliphatic chain and an epoxide reactive group: Glycidyldimethyldodecylammonium chloride (GDDAC). Fungicidal properties of this molecule have been proven. Secondly, afterglows issued from atmospheric pressure Dielectric Barrier Discharges (DBDs), can assist QAC grafting on cellulose. The efficiency of the reaction is improved by adding a few percentage of oxygen in nitrogen DBD. Antifungal efficiency of GDDAC grafting on wood sawdust is finally shown demonstrating the great interest of such process. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Interaction between poly(4-vinylpyridine-graft-bromodecane) and textile blue basic dye by spectrophotometric study

cited By 1International audienceThe interactions between poly(4-vinylpyridine-graft-bromodecane) (P4VPBrD) and textile blue basic (TBB) dye in aqueous solution were investigated by a spectrophotometric method at room temperature, considering that the electrostatic force is the main binding force and that the color change during the combination is due to the transformation of dye species of acidic form into bound basic form as well as the bathochromic and hypsochromic effects of conjugation. The formation of an isosbestic point in the absorption spectra of textile blue basic dye species of acidic form was explained based on a new consideration about the solution equilibrium. An application based on the interaction of P4VPBrD with the basic coloring agent is presented. Tests were carried out to estimate the retention rate of the dye by P4VPBrD. © 2012 Springer Science+Business Media Dordrecht

Associative polymers for EOR - towards a better understanding and control of their adsorption in porous media

cited By 0International audienceAdsorption properties of associative polymers (AP) were investigated in porous media to evaluate the performances of these chemicals as EOR mobility control agents. Two different AP were studied. For AP Type 1, results indicated a strong adsorption as compared to equivalent non associative polymers and a poor in-depth propagation. AP Type 2 were easily injected, and their adsorption was found to depend on the ionic strength of the dilution brine. It is thus shown that: i) AP adsorption is a significant parameter for the success of polymer flooding operations since it can impair injectivily and reduce the effective viscosity of the polymer solution, and ii) a control of AP adsorption can be achieved through an adjustment of the injection conditions

Associative polymers for EOR - towards a better understanding and control of their adsorption in porous media

cited By 0International audienceAdsorption properties of associative polymers (AP) were investigated in porous media to evaluate the performances of these chemicals as EOR mobility control agents. Two different AP were studied. For AP Type 1, results indicated a strong adsorption as compared to equivalent non associative polymers and a poor in-depth propagation. AP Type 2 were easily injected, and their adsorption was found to depend on the ionic strength of the dilution brine. It is thus shown that: i) AP adsorption is a significant parameter for the success of polymer flooding operations since it can impair injectivily and reduce the effective viscosity of the polymer solution, and ii) a control of AP adsorption can be achieved through an adjustment of the injection conditions