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Aerosol-OT Sodium

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-... [Pg.149]

In some cases a single surfactant may be sufficient for lowering y far enough for microemulsion formation to become possible examples include Aerosol OT (sodium diethyl hexyl sulphosuccinate) and many nonionic surfactants. [Pg.309]

Sodium di(ethylhexyl)sulfosuccinate (Aerosol-OT, sodium docusate) [577-11-7] M 444.6. Dissolve it in MeOH and the inorganic salts which precipitate are filtered off. Water is added and the solution is extracted several times with hexane. The residue is evaporated to one-fifth its original volume, benzene is added and azeotropic distillation is continued until no water remains. The solvent is evaporated. The white residual soHd is crushed and dried in vacuo over P2O5 for 48hours [El Seoud Fendler J Chem Soc, Fcrcukiy Trans 1 71 452 1975]. [Beilstein 4 IV 114.] It solubilises major myelin trans membrane proteolipids, and forms reverse micelles in hydrocarbon solvents. [Pg.551]

Aerosol OT (sodium diethylhexylsulfosuccinate) Didodecyldimethylammonium bromide Nonionic surfactant of the polyethylene glycol alkyl ether type the alkyl chain contains i carbon atoms and the polar group j ethylene glycol units Critical micelle concentration... [Pg.164]

The reverse micelles refer to the aggregates of surfactants formed in nonpolar solvents, in which the polar head groups of the surfactants point inward while the hydrocarbon chains project outward into the nonpolar solvent (Fig. 7) [101-126], Their cmc depends on the nonpolar solvent used. The cmc of aerosol-OT (sodium dioctyl sulfosuccinate, AOT) in a hydrocarbon solvent is about 0.1 mM [102]. The AOT reverse micelle is fairly monodisperse with aggregation number around 20 and is spherical with a hydrodynamic radius of 1.5 nm. No salt effect is observed for NaCl concentration up to 0.4 M. Apart from liquid hydrocarbons, recently several microemulsions are reported in supercritical fluids such as ethane, propane, and carbon dioxide [111-113]. [Pg.303]

All the systems described thus far require relatively high salinity, which is considered to be critical in soil remediation processes [60]. Another approach for effective microemulsification of organic liquids is the use of co-surfactants. Sodium mono- and dimethyl naphthalene sulphonate were found to be effective co-surfactants in formulations with Aerosol OT (sodium bis(2-ethylhexyl) sulphosuccinate) for diverse chlorinated hydrocarbons and their mixtures between 15 and 25°C [60, 61]. All types of microemulsions could be obtained with this approach. [Pg.308]

In 1997, Eastoe et al. launched a study of fluorinated anionic sulfosuccinate surfactants, which are analogous to the hydrocarbon Aerosol-OT (sodium bis-2-ethylhexyl sulfosuccinate, AOT) (13,24-26, 27 a). Example molecular structures are shown on Figure 1. Furthermore, fluoroalkylphosphates have been assessed for C02-activity (27 b, c). A detailed presentation of these systems is given in section 2 below. In 2001, Erkey and co-workers also showed interest in these very promising sulfosuccinate surfactants (28, 29). Small-angle X-ray scattering (SAXS) was used to characterize di-HCF4 at 0.1 M in CO2 at 27 °C and 345 bar for w between 0 and 20 (29). [Pg.287]

Most commonly, in the emulsion polymerization of vinyl acetate, anionic surfactants are used either alone or in combination with a protective colloid. Typical examples of surfactants which have found application are Aerosol OT (sodium dioctylsulfosuccinate), alkyl aryl sulfonate salts (e.g., Santomerse-3), sodium lauiyl sulfate, etc. A study of the kinetics of the vinyl acetate polymerization in the presence of sodium lauryl sulfate indicated that the rate of polymerization was proportional to the square root of the initiator concentration and the 0.25th power of the number of particles. The number of particles were proportional to the 0.5th 0.05 power of the surfactant concentration but independent of the level of potassium persulfate. The intrinsic viscosity of the final polymer was said to be independent of the initiator concentration and of the munber of polymer particles. These observations were said to suggest that the mechanism of the vinyl acetate polymerization in emulsion resembles that of vinyl chloride [153]. [Pg.256]

While the various intervals in emulsion polymerization of VAc have a profound affect on the development of molar mass, other components added during the polymerization can also affect molar mass. Lee and Mallinson [21] determined that simple components such as surfactants can profoundly influence molar mass. They studied Aerosol OT [sodium bis-(2-ethylhexyl) sulfosuccinate] (AOT) and determined it can change the molar mass of a product by broadening the molar mass distribution. They reported an increase in polydispersity from 4.2-14 when AOT was substituted for sodium dodecyl sulfate in a VAc system. They attributed these results to significant chain transfer effects of AOT. [Pg.296]

Acrylamide (AM) was polymerized in Aerosol OT (sodium l,4-bis(2-ethylhexyl) sulfosuccinate, AOT) reverse micelles (d 6 run) where the oil was toluene, benzene, decane or heptane [47-56]. [Pg.786]

Preparation of iron oxide magnetic nanoparticles and their encapsulation with polymers in W/0, i.e. inverse microemulsion polymerization, was also applied by O Connor et al. [167]. Inverse microemulsion polymerization was used to prepare submicron hydrophilic magnetic latex containing 5-23 wt% iron oxide. AM and crosslinker MBA were added to an aqueous suspension of previously synthesized iron oxide nanoparticles (6 wt%) this aqueous phase was dispersed in a aerosol OT (sodium l,4-bis(2-ethylhexoxy)-l,4-dioxobutane-2-sulfonate) (AOT)-toluene solution to form a W/O microemulsion, followed by polymerization with AIBN or V-50 as initiator. The particle size (80-180nm)was controlled by tuning the concentration of the water-soluble crosslinker agent as well as the amount of surfactant with respect to water [168]. [Pg.272]

Aerosol OT (sodium diethylhexyl sulfosuccinate) is a surfactant known to form readily reverse micelles, in organic nonpolar solvents [4], Sulfosuccinates absorb slightly UV light at short wavelengths. However, the ester group is sensitive to hydrolysis, so they can only be used in near neutral solutions. [Pg.13]

There are also surfactants which display monomer h-mer association in nonpolar solvents [12,14] they often contain two hydrocarbon tails. Dialkyl sulfosucci-nates [15-22], dinonylnaphthalenesulfonates [23, 24] and phosphatidylcholines [25-31] are perhaps the most extensively studied. Aggregation numbers typically range from 12 to about 30, but dodecylammonium benzoate forms a trimer in a monomer h-mer association [32]. Even with these surfactants, the definition of a CMC is not without ambiguity. Thus in the case of Aerosol OT (sodium di(2-ethylhexyl) sulfosuccinate, AOT) [33-36], a premicellar linear trimer which undergoes a conformational transition to a closed trimeric unit has been implicated. [Pg.199]

In smectic mesophase of aerosol-OT—water decanol-decanoate-water and 4-n-butyloxybenzylidene-4 -acetoaniline. (Aerosol-OT = sodium l,4-bis(2-ethylhexyl)sulfosuccinate). ... [Pg.444]

From [75Setl], (Aerosol-OT=sodium l,4-bis(2-ethylhexyl)sulfosuccinate). [Pg.474]

It is well known that the effectiveness of hydrophobed silica-polydimethylsiloxane antifoams in aqneons solntions deteriorates markedly during both use [1-7] and dispersal as an emnlsion [6], Resnlts of Marinova et al. [7] illustrating this effect are reproduced in Figure 6.1. Here the time taken for foam collapse after repeated shake-quiescent cycles of a solution of 0.01 M aerosol OT (sodium bis-octyl sulfo-succinate) containing -0.1 g dm of hydrophobed silica-polydimethylsiloxane antifoam is plotted against number of cycles. Antifoam was added neat to the solution without predispersal. Marked deactivation of the antifoam is observed after 50-60 cycles. [Pg.343]

A study [17] has been made of the effect of a dialyzed styrene-acrylate copolymer latex on the foam and the resistance to antifoam of three different surfactants—SDS, aerosol OT (sodium bis-diethylhexyl sulfosucdnate), and Triton X-100 (OP.EOjq)— all at a nominal concentration of 0.03 M. The polymer particles were dispersed in the surfactant solutions at a proportion of 25.5 wt.%. Adsorption of the surfactant onto the polymer particles significantly reduced the concentration of free surfactant in solution. A comparison was therefore made between the foam and resistance to antifoam behavior of the latex polymer-containing surfactant solution and a surfactant solution at the same depleted surfactant concentration, but containing no polymer. These depleted solutions were all submicellar—from about 80% to 99.9% of the surfactant (depending on the surfactant) was lost by adsorption onto the polymer-water surface. [Pg.488]

AOT, aerosol OT, sodium bis-diethylhexyl sulfosuccinate in 3 x 10 M EDTA SDS, sodium dodecyl sulfate TX-lOO, octylphenol ethoxylated (OP.EOlO) in 1.55 x 10 M NaCl. [Pg.490]

Whether an emulsion is 0/W or W/0 depends on a number of variables like oihwater ratio, electrolyte concentration, temperature, etc. For most of this centiuy, emulsion chemists have known that surfactants more soluble in water tend to make 0/W emulsions and surfactants more soluble in oil tend to make W/0 emulsions. This is the essence of Bancroft s rule, which states that the continuous phase of an emulsion tends to be the phase in which the emulsifier is preferentially soluble. The word soluble is misleading, however, for two reasons. Firstly, a surfactant may be more soluble in, say, oil than in water in a binary system, but in the ternary system of oil -I- water + surfactant it may partition more into water. A good example of this is with the anionic surfactant Aerosol OT (sodium bis-2-ethylhexylsulfosuccinate) which dissolves in heptane at 25 C up to at least 0.5 m but has a solubility limit in water of only 0.03 M. An emulsion made from equal volumes of water and heptane at 25 °C is 0/W, however. Secondly, no distinction is made between the solubility of monomeric or aggregated surfactant in oil or water. We will see that this is an important omission. [Pg.2]

Abbreviation ACN 1,1 -azobiscyclohexane-l-carbonitrile AEN 2,2 -azobisisobutyronitrile BPO benzoyl peroxide DCPC dicyclohexyl peroxidicarbonate DEE diethyl ehter DMF dimethylformamide DTBP di-tert-butyl peroxide LPO lauroyl peroxide TBPB len-butyi perbenzoate TBPO ferr-butyl peroctoate THE tetrahydrofuran SDS sodium dodecylsulfate Aerosol OT sodium dioctyl sulfosuccinate tBPP fert-butyl pervivalate. [Pg.468]


See other pages where Aerosol-OT Sodium is mentioned: [Pg.137]    [Pg.183]    [Pg.766]    [Pg.610]    [Pg.156]    [Pg.369]    [Pg.254]    [Pg.292]    [Pg.119]    [Pg.412]    [Pg.24]    [Pg.473]    [Pg.313]    [Pg.346]    [Pg.115]    [Pg.245]   


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Aerosol-OT

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