Surfactants foaming properties

The value of the 1.0X 1.5X brine foam volume ratio at 75 C may be taken as a measure of the sensitivity of surfactant foaming properties to aqueous phase salinity. Values of this ratio determined at 75 C in the presence of decane are summarized below ... 

Unlike previous one atmosphere foam test designs, the present test permits the effect of the oil phase on surfactant foaming properties to be determined. Refined hydrocarbons were used as model oil phases. Results summarized in Tables I and Figure 3 indicated that the presence of hydrocarbons decreased the foam stability. Examination of Table I indicated that the presence of a hydrocarbon substantially reduced the 75 C foam volumes produced by AES and AESo surfactants. 

Table II. Effect of an Oil Phase and Aqueous Phase Salinity on Surfactant Foaming Properties...

Surfactant foaming properties are related to surfactant chemical structure parameters such as hydrophobe size, ethylene oxide chain length, and hydrophile functional group. 

Surfactant foaming properties are related to oil phase composition. The composition of the residual oil will change in the course of a COj EOR project. The optimum COj mobility control agent may thus change during the course of the project. 

Polyall lene Oxide Block Copolymers. The higher alkylene oxides derived from propjiene, butylene, styrene (qv), and cyclohexene react with active oxygens in a manner analogous to the reaction of ethylene oxide. Because the hydrophilic oxygen constitutes a smaller proportion of these molecules, the net effect is that the oxides, unlike ethylene oxide, are hydrophobic. The higher oxides are not used commercially as surfactant raw materials except for minor quantities that are employed as chain terminators in polyoxyethylene surfactants to lower the foaming tendency. The hydrophobic nature of propylene oxide units, —CH(CH2)CH20—, has been utilized in several ways in the manufacture of surfactants. Manufacture, properties, and uses of poly(oxyethylene- (9-oxypropylene) have been reviewed (98). 

Many of the surfactants made from ethyleneamines contain the imidazoline stmcture or are prepared through an imidazoline intermediate. Various 2-alkyl-imidazolines and their salts prepared mainly from EDA or monoethoxylated EDA are reported to have good foaming properties (292—295). Ethyleneamine-based imida zolines are also important intermediates for surfactants used in shampoos by virtue of their mildness and good foaming characteristics. 2- Alkyl imidazolines made from DETA or monoethoxylated EDA and fatty acids or their methyl esters are the principal commercial intermediates (296—298). They are converted into shampoo surfactants commonly by reaction with one or two moles of sodium chloroacetate to yield amphoteric surfactants (299—301). The ease with which the imidazoline intermediates are hydrolyzed leads to arnidoamine-type stmctures when these derivatives are prepared under aqueous alkaline conditions. However, reaction of the imidazoline under anhydrous conditions with acryflc acid [79-10-7] to make salt-free, amphoteric products, leaves the imidazoline stmcture essentially intact. Certain polyamine derivatives also function as water-in-oil or od-in-water emulsifiers. These include the products of a reaction between DETA, TETA, or TEPA and fatty acids (302) or oxidized hydrocarbon wax (303). The amidoamine made from lauric acid [143-07-7] and DETA mono- and bis(2-ethylhexyl) phosphate is a very effective water-in-od emulsifier (304). 

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. 

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. 

These higher foaming properties are very useful for such cosmetic formulations as shampoos, showerbaths, and so on. This is the same with the forming of fine bubbles and the improving of foam stability of other surfactants such as, for example, alkyl ether sulfates due to the combination with ether carboxylates [57,67-69] (Table 9). 

Due to the good lime soap dispersing properties it is possible to improve the foaming properties of hard water-susceptible surfactants. Improvement of the formulation of a fatty acid soap by laureth-17 carboxylic acid, sodium salt [57,62], and an amidether carboxylate [62] has been described. 

Muller et al. [80] described the use of IOS surfactants together with the sulfonate of a C12-C24 unsaturated fatty acid containing one to six double bonds in shampoo formulations they combine good detergency with good foam properties and mildness to the skin. 

The basis for the foam properties is given by interfacial parameters. Although correlations have been shown between a single parameter and foam properties, there is still a lack in a general correlation between interfacial properties and the foam behavior of complex systems in detergency. The simplest approach to correlate interfacial parameters to foam properties is the comparison of the surface activity measured by the surface tension of a surfactant system and foam stability. 

Structured products, such as cosmetics, detergents, surfactant foams, inks, paints, drugs, foods and agrochemicals, combine several functions and properties in a single product. Design of these structured products involve the creation and the control of the particle size distribution in operations such as crystallization, precipitation, generation of aerosols, and nanoparticles as well as... 

Surfactants retain their foaming properties in natural waters in concentrations as low as 1 mg/L, and although such concentrations are nontoxic to humans [24], the presence of surfactants in drinking water is esthetically undesirable. More important, however, is the generation of large volumes of foam in activated sludge plants and below weirs and dams on rivers. 

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. 

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))...

The foam properties of products are mainly governed by the surfactant system and the use of anti-foams discussed below. Besides this the chemical composition of the product or the washing liquor, for example electrolyte content and soil, strongly influences the foam properties. Physical parameters such as temperature and pH value or mechanical input in the system additionally have to be taken into account. 

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