Foaming properties, alcohol

Glasl [149] reported the foaming properties of several alcohol sulfates and alcohol ether sulfates using the perforated disk method as described in the DIN standard 53902. All values were obtained at 0.28 g/L surfactant concentration, both in distilled water and in water of 16°dH hardness at 20, 40, and 60°C. The results are shown in Figs. 15-17. 

The foaming properties of sodium symmetrical secondary alcohol sulfates, sodium secondary alcohol sulfates, isomeric sodium secondary pentanol sulfates, and sodium linear alcohol sulfates were studied by Dreger et al. [72] via the Ross-Miles test [150] at 46°C. Within the linear series sodium tetradecyl sulfate produces the largest amount of foam. The influence of several electrolytes was also studied. 

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. 

Alcohol ether sulfates are used in mixture with sulfonates, either alkyl-benzenesulfonates or a-olefinsulfonates, and other surfactants, such as fatty alkanolamides, in manual liquid dishwashing detergents and light-duty detergents. These combinations show the excellent emulsifying and foaming properties required in dishwashing. 

FIG. 6 Influence of the temperature on the foaming properties of an alkyl ether carboxylate compared to an alcohol ethoxylate. 0.1% solution, pH = 11. (From Refs. 61 and 64.)... 

Alcohol sulfates (AS) are usually manufactured by the reaction of a primary alcohol with sulfur trioxide or chlorosulfonic acid followed by neutralization with a base. These are high foam surfactants but they are sensitive to water hardness and higher levels of phosphates are required. This latter requirement has harmed the market for this type of detergent, but they are 2% of production for the major household surfactant market. Sodium lauryl sulfate (R = Cn) is a constituent of shampoos to take advantage of its high-foaming properties. 

Pour point, viscosity, cloud point, wetting power and foam properties, being important advantages of SAE, are presented here in comparison with other commercial products derived from primary alcohols (Ziegler and Oxo) or nonylphenol (branched chain). 

Figure 32. Foam properties of propylene oxide adduct of secondary alcohol ethoxylate compared with those of others. Test conditions method—Ross-Miles (JIS-K-3362) surfactant concentration—1.0 wt % water temperature—25°C. ((- -) Cn.H SAE (7EO) + (4.5PO) (-1-) CI2 + Ii PAE (7EO) + (4.5PO) (-U-) HPE (8EO) + (4.5PO))...

Correlation equations relating surfactant chemical structure to performance characteristics and physical properties have been established. One atmosphere foaming properties of alcohol ethoxyl-ates and alcohol ethoxylate derivatives have been related to surfactant hydrophobe carbon chain length, ethylene oxide content, aqueous phase salinity, and temperature. Similar correlations have been established for critical micelle concentration, surfactant cloud point, and surfactant adsorption. 

Foam exhibits higher apparent viscosity and lower mobility within permeable media than do its separate constituents.(1-3) This lower mobility can be attained by the presence of less than 0.1% surfactant in the aqueous fluid being injected.(4) The foaming properties of surfactants and other properties relevant to surfactant performance in enhanced oil recovery (EOR) processes are dependent upon surfactant chemical structure. Alcohol ethoxylates and alcohol ethoxylate derivatives were chosen to study techniques of relating surfactant performance parameters to chemical structure. These classes of surfactants have been evaluated as mobility control agents in laboratory studies (see references 5 and 6 and references therein). One member of this class of surfactants has been used in three field trials.(7-9) These particular surfactants have well defined structures and chemical structure variables can be assigned numerical values. Commercial products can be manufactured in relatively high purity. 

Alcohol ethoxylates and alcohol ethoxylate derivatives were chosen for study based on their predicted foaming properties, thermal and chemical stability, salinity tolerance, and adsorption characteristics. Table 1 illustrates the classes of surfactants used and the shorthand surfactant naming system employed. Except when noted, surfactants were developmental ENORDET surfactants from Shell Chemical Company or were research samples synthesized in our laboratory or at Koninlijke/Shell Laboratorium, Amsterdam. AES 810-2.6A was obtained from GAF Corporation. 

The foaming properties of a large number of alcohol ethoxylates have been reported in the literature(13) (Table 3). No oil phase was present in these tests. Surfactants were obtained from two different suppliers. 

Various anionic derivatives of alcohol ethoxylates have been shown to possess improved saline media foaming properties in the... 

Foaming properties of alcohol ethoxylates and alcohol ethoxylate derivatives are related to chemical structure features such as hydrophobe size and linearity, ethylene oxide chain length, and the terminating group at the end of the ethylene oxide chain. Foaming properties may be mathematically related to chemical structure parameters using multiple correlation analysis. ... 

Alcohol sulfates are not stable in acid and are used in alkaline formulations. C12-C16 alcohol sulfates have excellent detergency, high foam, and good wetting properties. Alcohol sulfates are fully biodegradable under aerobic and anaerobic conditions and compete in performance with petrochemical-derived linear alkyl-benzene sulfonates (LABS). 

By far, the greatest apphcation of fatty alcohol is in the manufacture of fatty alcohol sulfate and fatty alcohol ether sulfate. These materials possess good foaming properties and ready biodegradability and are extensively used as base surfactants for laundry detergent products, shampoos, dishwashing liquids, and cleaners. 

Other coco-based surfactants are sulfosuccinates formed by the reaction of coco fatty alcohol with maleic anhydride and further reaction with sodium sulfite or bisulfite. This product possesses good foaming properties, is compatible with soap, and is a good lime dispersant. It is used in toilet soap formulation, shampoos, hand cleaning pastes, and for scouring raw wool. Its ether variant, with 2-4 moles ethylene oxide, forms intense, finely structured foam and is used in combination with ether sulfate in baby shampoos and bath preparations. 

This formulation has excellent wetting, detergent, rinsing and foaming properties. It is recommended as a medium duty cleaner for truck bodies, floor scrubs, wax strippers, etc. This product is clear from -5C to 70C. This formula would require approximately 4 times as much sodium xylene sulfonate as the amount of Monateric CEM-36 used to achieve clarity. Other nonionic ethoxy-lates, such as those based on primary alcohol or alkyl phenol may... 

Patist, A., Axelberd, T., and Shah, D. O., Effect of long chain alcohols on micellar relaxation times and foaming properties of sodium dodecyl sulfate solutions, J. Colloid Interface Sci., 208, 259-265 (1998). 

The strategy of wort supplementation with metal ions, lipids and yeast foods , with the aim to improve fermentation performance, is reviewed in detail by Gibson (2011). Among metal ions, zinc and magnesium were identified as elements with a crucial role in wort fermentation, the supplementation of which led to reduced attenuation time (Zn, Mg), increased uptake of trisaccharides (Zn) and increased ethanol production (Zn) and tolerance (Mg). It was also found that zinc has an indirect effect on the synthesis of higher alcohols and esters as well as on foam properties. Calcium supplementation of wort may only be beneficial when Ca concentration is limited in the local water supply (Gibson, 2011). 

Nonionic surfactants, such as fatty ethoxylated alcohols, are rarely used as primary surfactants in shampoos because of their poor foaming properties (Table 6.8). 

Poorly soluble alkanolamine salts of fatty saturated acids in or more fatty alcohols (tallow, cetyl, and steryl alcohols), which are good for conditioning but reduce foaming properties. 

The broad cut (Ciq-Cis) alcohol sulphates represent a compromise of cost/performance in terms of detergency, solubility and foaming properties. This product can partially or totally substitute other anionics in liquid and powder detergent formulations with the advantages of good biodegradability and low "defatting" action which is important for human tissue and delicate natural or synthetic fibres. 

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