Aerosol® Sulfosuccinates

Results can sometimes be unexpected. The first study of this type made use of labeled Aerosol OTN [111], an anionic surfactant, also known as di-n-octylsodium sulfosuccinate. The measured F was twice that in Eq. III-93 and it was realized that hydrolysis had occurred, that is, X + H2O = HX + OH , and that it was the undissociated acid HX that was surface-active. Since pH was essentially constant, the activity of HX was just proportional to C. A similar behavior was found for aqueous sodium stearate [112]. 

LialkylSulfosuccinates. Introduced in 1939 by the American Cyanamid Company under the Aerosol trademark, dialkyl sulfosuccinates have become widely used specialty surfactants (Table 8) (9). Within the limitations in hydrolytic stabiUty imposed by the presence of the ester groups, sulfosuccinates are mild, versatile surfactants used when strong wetting, detergency, rewetting, penetration, and solubilization effectiveness is needed. 

Sodium di(ethylhexyl)sulfosuccinate (Aerosol-OT) [577-11-7] M 444.6. Dissolved in MeOH and inorganic salts which ppted were filtered off. Water was added and the solution was extracted several times with hexane. The residue was evaporated to one fifth its original volume, benzene was added and azeotropic distillation was continued until no water remained. Solvent was then evaporated. The white solid was crushed and dried in vacuum over P2O5 for 48h [El Seoud and Fendler J Chem Soc, Faraday Trans I 71 452 /9751. 

Chemical Designations - Synonyms Aerosol Surfactant Alrowet D65 Bis(2-ethylhexyl)sodlum Sulfosuccinate Di(2-ethylhexyl)Sulfosuccinate, Sodium Salt Sodium Dioctyl Sulfosuccinate Chemical Formula C8H,700CCH2CH-(S03Na)C00C8H,7. 

Di(2-ethylhexyl)sodium sulfosuccinate (diisoocytyl sulfosuc-cinate. Aerosol OT, AOT) was obtained from Aldrich and purified by... 

Surfactants employed for w/o-ME formation, listed in Table 1, are more lipophilic than those employed in aqueous systems, e.g., for micelles or oil-in-water emulsions, having a hydrophilic-lipophilic balance (HLB) value of around 8-11 [4-40]. The most commonly employed surfactant for w/o-ME formation is Aerosol-OT, or AOT [sodium bis(2-ethylhexyl) sulfosuccinate], containing an anionic sulfonate headgroup and two hydrocarbon tails. Common cationic surfactants, such as cetyl trimethyl ammonium bromide (CTAB) and trioctylmethyl ammonium bromide (TOMAC), have also fulfilled this purpose however, cosurfactants (e.g., fatty alcohols, such as 1-butanol or 1-octanol) must be added for a monophasic w/o-ME (Winsor IV) system to occur. Nonionic and mixed ionic-nonionic surfactant systems have received a great deal of attention recently because they are more biocompatible and they promote less inactivation of biomolecules compared to ionic surfactants. Surfactants with two or more hydrophobic tail groups of different lengths frequently form w/o-MEs more readily than one-tailed surfactants without the requirement of cosurfactant, perhaps because of their wedge-shaped molecular structure [17,41]. 

Aerosol OT (dioctylsulfosuccinate, sodium salt sodium bis(2-ethylhexyl)-sulfosuccinate) 444.6 2.5 a... 

AOT sodium bis(2-ethyl-l-hexyl) sulfosuccinate, aerosol OT ARMES affinity based reverse micellar extraction and separation... 

RME shows particular promise in the recovery of proteins/enzymes [12-14]. In the past two decades, the potential of RME in the separation of biological macromolecules has been demonstrated [15-20]. RMs have also been used as media for hosting enzymatic reactions [21-23]. Martinek et al. [24] were the first to demonstrate the catalytic activity of a-chymotrypsin in RMs of bis (2-ethyl-hexyl) sodium sulfosuccinate (Aerosol-OT or AOT) in octane. Since then, many enzymes have been solubilized and studied for their activity in RMs. Other important applications of RME include tertiary oil recovery [25], extraction of metals from raw ores [26], and in drug delivery [27]. Application of RMs/mi-croemulsions/surfactant emulsions were recognized as a simple and highly effective method for enzyme immobilization for carrying out several enzymatic transformations [28-31]. Recently, Scheper and coworkers have provided a detailed account on the emulsion immobiUzed enzymes in an exhaustive review [32]. 

Sodium bis(2-ethyl-l-hexyl) sulfosuccinate (Aerosol OT, AOT) sodium do-decylbenzene sulfonate (SDBS) sodium di-2-ethyl hexyl phosphate (NaDEHP) dioleyl phosphoric acid (DOLPA) di(tridecyl) phosphoric acid (DTDPA) sodium dodecyl sulfate (SDS) 1,3-dilauroyl glycerol-2-disodium phosphate (2-modified 1,3-diacyl glycerol)... 

Older compilations about the state of the art can be found in several review articles [41 -47]. It is surprising that most work is carried out with the surfactant bis-ethylhexyl-sulfosuccinate (tradename AOT or Aerosol OT). The reasons seem to be the variability of the obtained reverse micelles (from very low up to high water concentrations) and the well-known phase behaviour of AOT with water and several oils [48,49]. AOT is approved for medical application, e.g. as an additive in suppositories, but not for food engineering. 

Docusate sodium, sodium di-(2-ethylhexyl) sulfosuccinate, aerosol OT (oral suspensions)... 

On the other hand addition of anionic emulsifiers, such as American Cyanamid Aerosol OT sodium dioctyl sulfosuccinate or Proctor Gamble Ivory Soap Flakes, markedly decreased volume resistitity. Thus, it seems that an impurity will con-... 

Aerosol A-102 Mono-ester sulfosuccinate surfactant Cytec... 

Holmes et al. (1998) performed two enzymatic reactions, the lipase-catalyzed hydrolysis of y>-nitrophenol butyrate and lipoxygenase-catalyzed peroxidation of linoleic acid, in w/c microemulsions stabilized by a fluorinated two-chained sulfosuccinate surfactant (di-HCF4). The activity of both enzymes in the w/c microemulsion environment was found to be essentially equivalent to that in a water/heptane microemulsion stabilized by Aerosol OT, a surfactant with the same headgroup as di-HCF4. The buffer 2-(A-morpholino)ethanesulfonic acid (MES) was used to fix the pH in the range 5-6. 

A = Aerosol MA (bis-1,3-dimethylbutyl sodium sulfosuccinate) B = Sipon WD (sodium lauryl sulfate)... 

A) AEROSOL A-102 M. HT 1800 DISODIUM ETHOXYLATED ALCOHOL (C10 - C ) HALF ESTER OF SULFOSUCCINIC ACID... 

Table 3.2. The physical properties of water in the water pool (WP) in reverse micelles of sodium bis-2-ethylhexyl sulfosuccinate (Aerosol OT or AOT) in isooctane. The spectroscopic properties of the hydrated electrons (e"aq) in the micellar water pool (Wo)...

Notes Aerosol OT is the dioctyl ester of sodium sulfosuccinic acid. 

The ultralow interfacial tension can be produced by using a combination of two surfactants, one predominantly water soluble (such as sodium dodecyl sulfate) and the other predominantly oil soluble (such as a medium-chain alcohol, e.g., pentanol or hexanol). In some cases, one surfactant may be sufficient to produce the microemulsion, e.g., Aerosol OT (dioctyl sulfosuccinate), which can produce a W/O microemulsions. Nonionic surfactants, such as alcohol ethoxylates, can also produce O/W microemulsions, within a narrow temperature range. As the temperature of the system increases, the interfacial tension decreases, reaching a very low value near the phase inversion temperature. At such temperatures, an O/W microemulsion may be produced. 

Granulation - the uses of HMX are such, that 6 classes are required Class A to Class F, inclusive - the coarsest crystals being retained on a US Std Sieve No 12 and finest cry stals passing thru a a No 325- The granulation is determined by aid of a mechanical sieve washer and pressure tank, using eth anol sat with HMX or a spray nozzle under water tap pressure, and a 2% solution of a wetting agent such as dioctyl sodium sulfosuccinate (Aerosol-OT)... 

The expected trends are born out for the low molecular weight enzymes ribonuclease-a, cytochrome-c, and lysozyme, as shown in Figure 2. These results are presented as the percentage of the protein transferred from a 1 mg/ml aqueous protein solution to an equal volume of isooctane containing 50 mM of the anionic surfactant Aerosol 0T, or AOT (di-2-ethylhexyl sodium sulfosuccinate). As anticipated, only at pH s lower than the pi was there any appreciable solubilisation of a given protein, while above the pi the solubilisation appears to have been totally suppressed. Note, however, that as the pH was lowered even further, there was a drop in the degree of solubilisation of the proteins. This was accompanied by the formation of a precipitate at the interface between the two phases, attributed to a denaturation of the protein. 

Borkovec et al. [59] also reported on a two-stage percolation process for the ME AOT (Aerosol OT, bis(2-ethylhexyl)sodium sulfosuccinate) system AOT-decane-water. The structural inversions were investigated using viscosity, conductivity, and electro-optical effect measurements. The viscosity results showed a characteristic profile with two maxima, which was interpreted as evidence for two symmetrical percolation processes an oil percolation on the water-rich side of the phase diagram and a water percolation process on the oil-rich side. 

Laboratory Treatments. Colorfastness of the dyed wool samples was determined in aqueous and nonaqueous media. Colored samples were cut into 2- X 2-in. squares and sandwiched between multifiber fabrics (Test Fabrics) and undyed wool fabrics of the same dimensions. The fabrics were loosely sewn together by hand with white cotton thread. Two surfactants were chosen for the aqueous treatments Tergitol NPX, a nonionic ethoxylated nonylphenol (Union Carbide) and Orvus WA, an anionic sodium alkyl sulfate (Proctor Gamble). Solutions of 0.1% surfactant in distilled water were prepared. Tests were run in 250-mL Erlenmeyer flasks at a liquor-to-cloth ratio of 50 1. The flasks were placed in an Eberbach constant-temperature shaker bath adjusted to 30 °C and an agitation of 40 cycles/min. Treatment time was 1 h, after which the samples were opened and allowed to dry on blotter paper. This same procedure was used for the nonaqueous treatments. Commercial grade tetrachloroethylene (R. R. Street Co.) with and without 1% Aerosol OT, the anionic surfactant sodium sulfosuccinate (Aldrich Chemical) was selected. The treated samples were removed from the liquids, opened, and dried on blotter paper in a ventilated hood. 

When a single chain anionic surfactant (such as sodium dodecyl sulfate, SDS) is used, it generally requires a cosurfactant for the formation of a microemulsion. A cosurfactant may not be needed to form a microemulsion if nonionic surfactant(s), certain types of cationic surfactants, or double-chain surfactants such as sodium l,4-bis(2-ethylhexyl)sulfosuccinate (Aerosol OT or simply AOT) are used. 

SYNS AEROSOL GPG ALCOPOL O ALPHASOL OT BEROL 478 BIS(ETHYLHEXYL) ESTER of SODIUM SULFOSUCCINTC ACID BIS(2-ETHYLHEX-YL)SODIUM SULFOSUCCINATE BIS(2-ETHYLHEX-YL)-S-SODIUM SULFOSUCCINATE 1,4-BIS(2-ETHYLHEXYL) SODIUM SULFOSUCCINATE 1,4-BIS(2-... 

Finally, in the discussion of reverse microemulsion systems, mention should be made of one of the most widely studied systems. The surfactant, sodium bis(2-ethylhexyl) sulfosuccinate or Aerosol-OT (AOT), is one of the most thoroughly studied reverse micelleforming surfactants since it readily forms reverse micelle and microemulsion phases in a multitude of different solvents without the addition of cosurfactants or other solvent modifiers. The phase behavior of AOT in liquid alkane/water systems is already well documented. Indeed, the first report of the existence of the formation of microemulsions in a supercritical fluid involved an AOT/alkane/ water system. A The spherical structure of an AOT/nonpolar-fluid/ water microemulsion droplet is shown in Fig. 1. In the now well-known structure, it can be seen that the two hydrocarbon tails of each AOT molecule point outward into the nonpolar phase (e g., supercritical fluid). These tails are lipophilic and are solvated by the nonpolar continuous phase solvent whereas the hydrophilic head groups are always positioned in the aqueous core. 

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