Carboxylated surfactants

Carboxylated surfactants (i.e. those for which the hydrophilic group is a carboxylic ion)... 

Observations of large contact angles in emulsions were first reported by Aronson and Princen [105,106]. The authors have studied oil-in-water droplets stabilized by anionic surfactant in the presence of various salts. Similar systems were studied by Poulin [110]. Anionic surfactants such as sulfate, sulfonate, or carboxylate surfactants [106,110] exhibit a good stability and a strong adhesion in the presence... 

Moreover, the adhesion depends strongly on the nature of the salt [105]. A pronounced difference is noted in Fig. 2.37, where the energy of adhesion with KCl, NaCl and LiCl are compared [110]. The system is much more adhesive with KCl. This is the contrary with a carboxylate surfactant [106,110]. This behavior is important because it suggests that the adhesion is linked to the solubility of the... 

Some carboxylate surfactants, such as long-chain fatty acids or their anionic esters with Coenzyme A, are precipitated in the presence ( fCSmd M + (Constantinides and Steim, 1986). Measurements of CMC in the presence of divalent ions should be avoided since the insoluble surfactant could introduce serious artifacts. Traces of transition-metal ions can catalyze autooxidation of some polyoxyethylene surfactants. In a recent article by Xiao (Xiao, 2006), interactions between anionic surfactant (SDS) micellar solutions and several familiar metal salt solutio b. 

Brine Increase in salinity Increase in divalent/monovalent ratio Decrease in pH (for carboxylated surfactants)... 

FIG. 10 The effect on emulsion type of changing the hydrophobic tail length of n-alkyl carboxylate surfactants. The question mark domain corresponds to the emulsion breaking region where emulsion type was found to be uncertain. C9, Cll, C13, and C15 stand for m = 9, 11, 13, and 15 in the above surfactant chemical structure (From Ref. 152.)... 

In view of the fact that one would expect interference with surfactant action by Ca(ll), Mg(ll), and other multivalent ions to be more severe with carboxylates than with sulfonates, the high interfacial tensions observed are discouraging from a practical point of view. However, there are interesting effects of structure between the salts studied, in particular between the cis and trans isomers, elaidate and oleate, and between compounds of different degrees of unsaturation. We are now preparing derivatives of these acids, in order to get more information on the effect of minor structure modifications. In addition, the possibilities of beneficial effects of cosurfactants have been as yet little explored. We believe it premature to conclude that carboxylate surfactants are of no utility. 

Rhodium complexes generated from the water-insoluble carboxylated surfactant phosphine 17 (n = 3, 5, 7, 9, 11) were used as catalysts in the micellar hydrogenation of a- and cyclic olefins, such as 1-octene, 1-dodecene, and cyclohexene, in the presence of conventional cationic or anionic tensides such as cetyltrimethylammo-nium bromide (CTAB) or SDS and co-solvents, e.g., dimethyl sulfoxide [15], After the reaction the catalyst was separated from the organic products by decantation and recycled without loss in activity. There is a critical relationship between the length of the hydrocarbon chain of the ligand 17 and the length and nature of the added conventional surfactant, for obtaining maximum reactivity. For example,... 

SOURCE Sandoz Chemicals Sandopan Carboxylated Surfactants Formula... 

Akypo . [Chem-Y GmbH] Carboxyls surfactants for cosmetics, industrial cleaning detrargent emulsifier, thickens. 

Similar transformations were used to demonstrate the possibility of using water/ CO2 microemulsions as reaction media, which were stabilized using the anionic perfluoropolyether ammonium carboxylate surfactant [PFPECOO] [NH4] [25]. No additional phase transfer catalysts are necessary under these conditions. For example, the reaction between potassium bromide and benzyl chloride to form benzyl bromide [Eqs. (2)-(4)] resulted in a much better yield in the H2O/CO2 system than in a conventional water-in-oil microemulsion. 

Sodium laureth-6 carboxylate Sodium laureth-13 carboxylate surfactant. It. duty cleaners Ammonium nonoxynoM sulfate surfactant. It. duty detergents Disodium PEG-4 cocamido MIPA sulfosuccinate Dodecylbenzenesulfonic acid surfactant, It.-colored epoxy curing agents Dimer acid, hydrogenated surfactant, lubricant ester derivs. 

Diisostearyl malate Myristoyl hydrolyzed collagen PEG-75 lanolin surfactant, MDI-based PU foam systems Silicone glycol copolymer surfactant, medicated cleansers Ricinoleamidopropyl betaine surfactant, medicated shampoo Sodium laureth-5 carboxylate surfactant, medicated soaps Sodium laureth-5 carboxylate surfactant, medicated treatments Disodium undecylenamido MEA-sulfosuccinate surfactant, medicinal soaps Potassium cocoate surfactant, metal cleaners Cl 2-15 pareth-9 DEA-lauryl sulfate Magnesium lauryl sulfate PEG-5 oleate PEG-14 oleate... 

The oriented-wedge theory is based on the concept that, for anionic surfactant emulsifiers, polyvalent metal ions will tend to form each coordinate to the polar groups of two surfactant molecules, forcing the hydrocarbon tails into a wedge-like orientation. In this case, the hydrocarbon tails in a close-packed interfacial layer are most easily accommodated if the oil phase is the continuous phase. As a result, aruonic surfactants associated with monovalent metal cations should tend to produce O/W emulsions, while those of polyvalent metal cations should tend to produce W/O emulsions. This works best for carboxylate surfactants. 

Abe, M., Schechter, R.S., Selliah, R.D., Sheikh, B. and Wade, W.H., Phase Behavior of Branched Tail Ethoxylated Carboxylate Surfactant/Electrolyte/Alkane Systems., J. Dispersion Sci. Technol., 8(2) 157-172 (1987). 

Miller [72] have made a similar identification of paraffinic carboxylate surfactants as the principal surfactant type released in the processing of Utah tar sands. 

Several methods have been developed specifically for naphthenic acids, a class which includes the surface active carboxylate surfactants. Naphthenic acids are present as a complex mixture of a number of homologues with only a small range in molar mass (166-450 mol/g), little change in solubility character, and have been difficult to assay using conventional analytical methods. Methods such as negative ion-mode mass spectrometry using fast atom bombardment (FABMS), have been successfully applied to the analysis of naphthenic acid mixtures [93, 94], Other promising techniques include fluoride ion chemical ionization mass spectrometry (FI-MS) [95], and electrospray ionization mass spectrometry (ESIMS), which may allow for the quantification of the various naphthenic acid fractions [96]. 

An FTIR method has also been developed for the determination of the naphthenic acids in oil sand process tailings [97]. In this method, a tailings sample is clarified by filtration (0.45 pm nominal pore size) then by ultrafiltration. Acidification to pH 2.5 with sulfuric acid ensures the acid form of all carboxylate functionalities and thus complete dissolution. The sample is then extracted with methylene chloride and evaporated to dryness. The naphthenic acid residue is dissolved in methylene chloride, the carbonyl stretching frequencies at 1708 and 1748 cm are observed and the corresponding absorbance values determined by FTIR. The method determines total organic carboxylates and therefore is sensitive to a broader range of structures than the carboxylate surfactants alone, but is sometimes used as an indicator of relative carboxylate surfactant concentrations, especially in studies of oil sand tailings pond samples. 

With guidelines for the critical concentrations and recognizing the preferential adsorption behaviour (dominance) of the carboxylate surfactant, an extremely wide range of oil sand processing behaviours can be nnderstood, as illustrated in a number of papers on the subject [70, 101-104,116],... 

Figure 20(b) illustrates a case where, at low NaOH addition, the concentration of carboxylate surfactants is near-zero and when the sulfonate surfactant concentration reaches Css, a first primary recovery maximum is observed. For the same oil sand processed at a moderately high NaOH addition level, the carboxylate snrfactant concentration has increased and reaches Ccs, which condition a second primary recovery maximum is observed. This two-peak processibdity curve is not an artifact, as it has been reproduced in mnltiple laboratory studies and also in continuous pilot-scale testing [104], This particular kind of oil sand (a type of channel margin origin) first gained notice when a so-called problem ore in a commercial extraction plant was encountered, for which traditional feed-forward fines-content process control strategies failed. 

These polymers were found to be useful surfaetants. For example, an OVAc- -PEG-OVAC triblock surfactant was found to emulsify up to 97% (v/v) CAV emulsion which was stable for at lease 48 h. An OVAc-Z -PEG diblock copolymer was used to form a 90% (v/v) C/W emulsion. The polymerization of the continuous aqueous phase led to the formation of highly porous crosslinked poly(acrylamide) (Fig. 5), which was comparable to that prepared with perfluoropolyether ammonium carboxylate surfactants [28]. 

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