Surfactants sulfated esters

Features Rec. for use alone or in combination with syn. lubricant components such as functional fluids, block polymers, low-foam surfactants, sulfated esters, etc. low foaming hard water stable contains P alkaline compat. 

Sulfated Natural Oils and Fats. Sulfated natural triglycerides were the first nonsoap commercial surfactants introduced in the middle of the nineteenth century. Since then sulfates of many vegetable, animal, and fish oils have been investigated (see also Fats AND FATTY oils). With its hydroxyl group and a double bond, ricinoleic acid (12-hydroxy-9,10-octadecenoic acid) is an oil constituent particularly suited for sulfation. Its sulfate is known as turkey-red oil. Oleic acid is also suited for sulfation. Esters of these acids can be sulfated with a minimum of hydrolysis of the glyceride group. Polyunsaturated acids, with several double bonds, lead to dark-colored sulfation products. The reaction with sulfuric acid proceeds through either the hydroxyl or the double bond. The sulfuric acid half ester thus formed is neutralized with caustic soda ... 

Compared with the fatty alcohol sulfates, which are also oleochemically produced anionic surfactants, the ester sulfonates have the advantage that their raw materials are on a low and therefore cost-effective level of fat refinement. The ester sulfonates are produced directly from the fatty acid esters by sulfona-tion, whereas the fatty alcohols, which are the source materials of the fatty alcohol sulfates, have to be formed by the catalytic high-pressure hydrogenation of fatty acids esters [9]. The fatty acid esters are obtained directly from the fats and oils by transesterification of the triglycerides with alcohols [10]. 

Fujiwara et al. used the CMC values of sodium and calcium salts to calculate the energetic parameters of the micellization [61]. The cohesive energy change in micelle formation of the a-sulfonated fatty acid methyl esters, calculated from the dependency of the CMC on the numbers of C atoms, is equivalent to that of typical ionic surfactants (Na ester sulfonates, 1.1 kT Ca ester sulfonates, 0.93 kT Na dodecyl sulfate, 1.1 kT). The degree of dissociation for the counterions bound to the micelle can be calculated from the dependency of the CMC on the concentration of the counterions. The values of the ester sulfonates are also in the same range as for other typical ionic surfactants (Na ester sulfonates, 0.61 Ca ester sulfonates, 0.70 Na dodecyl sulfate, 0.66). 

There are many parallels between phosphates and sulfates of aliphatic alcohols. Both types of surfactants contain ester bonds undergoing hydrolysis in acid solutions. In that case the starting materials are received once more. By dry heating of the salts above a temperature of 140°C destruction will occur forming the corresponding alkenes and an inorganic acid salt. In the same way as sulfonic and sulfinic acids are formed by C-S bonds, C-P bonds lead to phosphonic and phosphinic acids. 

When ethoxylated nonylphenol and polyethylene glycol is treated with a mixture of H2S04 and H3P04 and neutralized with an alkali metal hydroxide or amine, surfactants containing sulfate esters and phosphate esters are obtained which cause little corrosion of metals such as surfaces of laundering equipments and automobiles [55]. 

Although sulfate is formed by hydrolysis of both alkyl and aryl sulfates, the pathway of degradation for aryl sulfates is controlled by the source of sulfur (Cook et al. 1999). The complex issues surrounding the hydrolysis of sulfate esters have been discussed (Kertesz 1999), and are illustrated by the number and substrate specificity of alkyl sulfatases for the surfactant 2-butyloctyl sulfate in Pseudomonas sp. strain AE-A (Ellis et al. 2002). 

Surfactants Methylene blue derivatives of sulfate esters and 652... 

Many anionic surfactants can react with a cationic dye such as methylene blue to form strong ion pairs that can be extracted by a suitable organic solvent and can be determined using colorimetric techniques. The anionic surfactants that respond to the methylene blue test are primarily the sulfonate (RS03 Na+) and the sulfate ester (R0S03 Na+) type substances. On the other hand, soaps and the alkali salts of fatty acids (C-10 to C-20) used in certain detergents do not respond to the above test. The various anionic surfactants and their characteristic structural features are presented in Figure 2.32.1. 

Data on the effects of surfactants on the hydrolysis of aryl sulfate esters have become available only recently. A non-ionic heterodisperse polyoxyethylene sorbitan monooleate surfactant, Polysorbate 80, was found to increase the observed rate constant for the acid-catalyzed hydrolysis of potassium 2,4-dichloronaphthyl sulfate by a factor of 16-3 at a surfactant concentration of 8 g/1, but an additional 5-fold increase... 

Surfactants with low foamability were found to be poor candidates for mobility control. In general, anionic surfactants appear superior in the static foam tests. Sulfate esters of ethyoxylated linear alcohols were slightly better than the other classes of surfactants. Most sulfonates do not appear compatible with even small amounts of calcium and, therefore, produce very little foam at the temperatures used, 75-120 F. 

The major subgroups of anionic surfactants include the alkali carboxylates (soaps), sulfates, sulfonates, and to a smaller degree, phosphates. The esterification of alcohol with sulfuric acid yields probably the best-studied surfactant, sodium dodecylsulfate or SDS. SDS, a sulfate ester, is an extremely effective emulsifier because of its high-electrostatic repulsion. Other sulfates are, for example, sulfated esters from fatty acids, sulfated ethers, and sulfated fats and oils. Sulfonates stem from the reaction of sulfonic acid with suitable substrates. Members of the class of sulfonates are, for example, sulfonic acid salts or aliphatic sulfonates. Other anionic surfactants include substances such as carboxylated soaps and esters of phosphoric acid. 

These compounds are permanently anionic and are moderately polar (surfactants are organic molecules that are surface active). This means that they concentrate on the surface of a liquid in which they are dissolved. Generally, these types of analytes contain both a hydrophobic and a hydrophilic segment. There are anionic, cationic, neutral, and amphoteric surfactants. They may be readily sorbed from water by reversed-phase SPE. Elution requires methanol or acetonitrile rather than ethyl acetate because of their polar, ionic functional groups, which are typically sulfate esters or sulfonic acids (Fig. 7.18). 

Some polysaccharides carry negative charges, by virtue of their uronic acid components and/or modification of OH groups as sulfate esters or cyclic acetals of pyruvic acid (CH3COCOOH) these can often be precipitated by cationic surfactants such as cetyltrimethylammonium bromide. They can also be fractionated on weak anion exchangers. For neutral polysaccharides, elaborate precipitation protocols involving initial removal of proteins and nucleic acids have to be used - a useful precipitant of the polysaccharide is 50% ethanol. 

Here cholesterol forms the hydrophobic tail of the surfactant and is attached via a spacer to a hydrophilic pyridinium sulfate ester head. The effect of molecular imprinting in these particles was elegantly demonstrated by an immunoprecipita-tion experiment, in which a,co-cholesterol-functionalized poly(ethylene oxide) was mixed with a suspension of the imprinted particles which led to bridging flocculation and precipitation. 

Definition Sodium salt of the sulfate ester of the PEG ether of coconut alcohol Formula R-(0CH2CH2)n0S03Na, R rep. alkyl groups from coconut oil, avg. n = 1-4 Uses Surfactant in cosmetics... 

Properties Anionic Uses Surfactant in cosmetics Sodium laureth-12 sulfate CAS 9004-82-4 (generic) 66161-57-7 EINECS/ELINCS 221-416-0 266-192-5 Synonyms PEG (12) lauryl ether sulfate, sodium salt PEG 600 lauryl ether sulfate, sodium salt Sodium 3,6,9,12,15,18,21,24,27,30,33,36-dodecaoxaoctatetracontyl sulfate Sodium POE (12) lauryl ether sulfate Definition Sodium salt of the sulfate ester of the PEG ether of lauryl alcohol Empirical C36H74O16S Na Formula CH3(CH2)ioCH2(OCH2CH2)nOS03Na, avg. n = 12... 

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. 

Ethoxylated alcohols Ethoxylated fatty acids Lauryl sulfates Mono and diglycerides Nonionic surfactants Phosphate esters Quaternary surfactants Sorbitan derivatives... 

The broad class of products described as sulfonates results from reactions that create a carbon-sulfur bond and utilizes sulfur VI reagent SO3 and its derivatives and adducts such as sulfuric acid. A smaller number of sulfonate products are prepared using sulfur IV reagent SOj as well as its derivatives and adducts such as sodium bisulfite. The preparation of sulfate esters involves the creation of carbon-oxygen-sulfur bonds, and can utilize SO3, sulfuric acid, or chlorosul-fonic acid to form alcohol sulfates that are labile and susceptible to hydrolysis in the presence of water as well as elimination reactions at elevated temperatures, and must be handled under milder conditions than sulfonates during formation and neutralization. Numerous older reviews and recent publications exist covering sulfonation and sulfation processes to produce surfactant products. " ... 

Which sulfate ester will you choose if you are interested in cleaning with the minimum amount of surfactant ... 

Synonyms Lanolin alcohols, ethoxylated, hydrogen sulfates, 2,2, 2"-nitrilotrisetha-nol salts Triethanolammonium PEG (5) lanolin ether sulfate Triethanolammo-nium POE (5) lanolin ether sulfate Definition Triethanolamine salt of the sulfate ester of laneth-5 Uses Emulsifier, surfactant, and skin conditioner in cosmetics Manuf./Distrib. Somerset Cosmetic Co, Variati TEA-lauraminopropionate CAS 14171-00-7 EINECS/ELINCS 238-015-1... 

Potentiometric titration of these compounds has been demonstrated after formation of the sulfate esters (101). They are titrated with a cationic surfactant, as described in Chapter 16. Since there are multiple hydroxyl groups available for the derivatization reaction, response factors must be developed for each commercial product. 

As the name implies, the sulfate ester surfactants contain a sulfuric acid ester group, which acts as the solubilizing group. Usually encountered as the alkali or ammonium salts, this class of materials has the generic formula ROSO M, where R is one of the hydrophobic groups described earlier. While the best-known members of this class are the simple straight-chain aliphatic materials such as SDS, many more complex structures are known and have found wide application. 

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