Highly soluble alcohol sulfates

A specific example, using model surfactant structures, was studied in the P G laboratories. Snoody found that the Krafft boundary could be altered dramatically by addition of a small methyl substituent on the chain of a methyl-substituted octadecylsulfate. P G has published some work on mixtures of midchain methyl-substituted alcohol sulfate surfactants. The resulting increased solubility of these alcohol sulfates called highly soluble alcohol sulfates (HSAS) allows use of long-chain alcohols, such as in laundry detergents under today s cold and hard water environments. The solubility effect is maximized when the methyl substitution is away from the end of the surfactant chain as shown in Figure 6.13. 

It has been reported that the LAS/AS mixed active system was produced by continuous oleum sulfonation of LAB followed by addition of the alcohol and more oleum to provide a tandem sulfation [40]. Tallow range alcohol sulfate (Ci6-is AS) was used in the past when U.S. wash temperatures were as high as 60°C. At these wash temperatures and in phosphate-built formulations the Ci6 18 AS gave very good detergency performance [41]. However, as U.S. washing temperatures decreased, C16.,8 AS was replaced by the more soluble shorter-chain ASs, such as C12.I8 or C,4, 5. 

Sodium alcohol sulfates have a limited solubility compared to sodium alcohol ether sulfates and are more suitable for cream, pearlized, and paste shampoos. Alcohol sulfates are more frequently used in general shampoo formulations in the United States than in Europe. Europe has moved toward alcohol ether sulfates for historical and traditional reasons, different availability of ethylene oxide, and possibly other technical reasons such as the more favorable dermatological properties of alcohol ether sulfates and their better behavior in hard waters. Triethanolamine alcohol sulfates are widely used in shampoos because of their comparatively high solubility in water, good foaming properties, and low irritancy. 

Colorless crystals triclinic structure density 2.435g/cm3 at 13°C melts above 315°C decomposes on further heating soluble in water, 28.6 g/lOOmL at 25°C highly soluble in boiling water, lOOg/100 mL at 100°C aqueous solution strongly acidic, pH of 0.1 M solution 1.4 insoluble in liquid ammonia decomposed by alcohol into sodium sulfate and sulfuric acid... 

The presence of highly electronegative atoms which can participate in hydrogen bonding is required for the solubility of polymers in water. Such groups include amines, imines, ethers, alcohols, sulfates, carboxylic acids and associated salts, and, to a lesser extent, thiols. The water solubility is also affected by pH and the formation of charged species. Thus the copolymer derived from vinylamine and vinyl sulfonate is not soluble in water, whereas the corresponding sodium salt of this copolymer is water-soluble. 

Alkyl ether sulfates (AES) are anionic surfactants obtained by ethoxy-lation and subsequent salfation of alcohols derived from feedstock or synthetic alcohol. AES, also known as alcohol ether sulfates, have low sensitivity to water hardness (Fig. 5.3), high solubility, and good storage stability at low temperature [4, 11]. 

AESs are anionic surfactants made by sulfating alcohol ethoxylates, and the degree of ethoxyl-ation typically ranges from 1 to 4, but predominantly 2-3 moles of ethoxylation (EO) are used with both natural and synthetic alcohol sources. AES provides numerous benefits such as high solubility. 

While the above examples demonstrate that product control to a significant extent is possible in oxythallation by careful choice of substrate or reaction conditions, the synthetic utility of oxythallation has been illustrated most convincingly by the results obtained with highly ionic thallium(III) salts, especially the nitrate (hereafter abbreviated TTN). Unlike the sulfate, perchlorate, or fluoroborate salts (165), TTN can easily be obtained as the stable, crystalline trihydrate which is soluble in alcohols, carboxylic acids, ethers such as dimethoxyethane (glyme), and dilute mineral acids. Oxidations by TTN can therefore be carried out under a wide variety of experimental conditions. 

The phase behavior of anionic-cationic surfactant mixture/alcohol/oil/ water systems exhibit a similar effect. First of all, it should be mentioned that because of the low solubility of the catanionic compound, it tends to precipitate in absence of co-surfactant, such as a short alcohol. When a small amount of cationic surfactant is added to a SOW system containing an anionic surfactant and alcohol (A), three-phase behavior is exhibited at the proper formulation, and the effect of the added cationic surfactant may be deduced from the variation of the optimum salinity (S ) for three-phase behavior as in Figs. 5-6 plots. Figure 16 (left) shows that when some cationic surfactant is added to a SOWA system containing mostly an anionic surfactant, the value of In S decreases strongly, which is an indication of a reduction in hydrophilicity of the surfactant mixture. The same happens when a small amount of anionic surfactant is added to a SOWA system containing mostly a cationic surfactant. As seen in Fig. 16 (left), the values of In S at which the parent anionic and cationic surfactant systems exhibit three-phase behavior are quite high, which means that both base surfactants, e.g., dodecyl sulfate... 

An interesting example of the salting out by nonelectrolytes in water was given by Grigorovich and Samoilov (69). They studied the solubility of praseodymium chloride and sulfate in water in the presence of various nonelectrolytes (methyl alcohol, ethyl alcohol, and diethyl ether.) Their results show that the decrease in solubility of praseodymium chloride is only of the order of a few percent but that this decrease is probably highly significant because praseodymium chloride is more soluble in pure methyl and ethyl alcohol than in pure water. (The... 

J-Butyl Ether. -Butyl ether is prepared by dehydration of -butyl alcohol by sulfuric acid or by catalytic dehydration over ferric chloride, copper sulfate, silica, or alumina at high temperatures. It is an important solvent for Grignard reagents and other reactions that require an anhydrous, inert medium. /7-Butyl ether is also an excellent extracting agent for use with aqueous systems owing to its very low water-solubility. 

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