Water sodium lauryl sulfate

Chloroxylenol 3% and cocamidopropyl PG-dimonium chloride phosphate 3%. Inactive ingredients water, sodium lauryl sulfate, cocamide DEA, propylene glycol, cocamidopropyl betaine, citric acid, tetrasodium EDTA,... 

Figure 1 shows the results obtained by Francois and Skoulios (27) on the conductivity of various liquid crystalline phases in the binary systems water-sodium lauryl sulfate and water-potassium laurate at 50 °C. As might be expected, the water-continuous normal hexagonal phase has the highest conductivity among the liquid crystals while the lamellar phase with its bimolecular leaflets of surfactant has the lowest conductivity. Francois (28) has presented data on the conductivity of the hexagonal phases of other soaps. She has also discussed the mechanism of ion transport in the hexagonal phase and its similarity to ion transport in aqueous solutions of rodlike polyelectrolytes. 

Figure 1. Electrical conductivity of liquid crystalline phases in water-sodium lauryl sulfate (Curve 1) and water-potassium laurate (Curve II) systems (27).

The independent measurements of surface tension were obtained by the tedious Wilhelmy plate method. Figure 3 illustrates such a calibration curve for one set of orifices and for five types of test fluids (methanol-water, ethanol-water, acetone-water, sodium lauryl sulfate in water saturated with methyl methacrylate, and polymethylmethacrylate latices). This is a "universal" calibration curve independent of the fluid being monitored. For the 63 data points shown in Figure 3, the least squares regression line is given by... 

A simple shampoo consists of a mixture of water, sodium lauryl sulfate, and an amide to make it foam. I heat the mixture and then I have to adjust the acidity. Most shampoos are neutral. If it s more basic than that, I adjust it with a citric acid solution. Then I cool it and check the viscosity, or how it flows. I don t want it to be either water-thin or molasses-thick, so I ll adjust the viscosity by using a 20 percent sodium chloride solution. Perfume and color are added to make it smell and look good. 

Detergents are substances including soaps that cleanse by micellar action A large number of synthetic detergents are known One example is sodium lauryl sulfate Sodium lauryl sulfate has a long hydrocarbon chain terminating m a polar sulfate ion and forms soap like micelles m water... 

Detergents are designed to be effective in hard water meaning water containing calcium salts that form insoluble calcium carboxylates with soaps These precipitates rob the soap of Its cleansing power and form an unpleasant scum The calcium salts of synthetic deter gents such as sodium lauryl sulfate however are soluble and retain their micelle forming ability even m hard water... 

The kinetics of vinyl acetate emulsion polymeriza tion in the presence of alkyl phenyl ethoxylate surfactants of various chain lengths indicate that part of the emulsion polymerization occurs in the aqueous phase and part in the particles (115). A study of the emulsion polymerization of vinyl acetate in the presence of sodium lauryl sulfate reveals that a water-soluble poly(vinyl acetate)—sodium dodecyl sulfate polyelectrolyte complex forms, and that latex stabihty, polymer hydrolysis, and molecular weight are controlled by this phenomenon (116). 

Alcohol sulfates decompose at high temperature. At 100°C they lose any associated water and at 150°C thermal decomposition begins. The organic part of the molecule is completely decomposed at 285 °C. Main decomposition substances of sodium lauryl sulfate are dilauryl ether and sodium pyrosulfate [64]. 

Water serves as a base value in this test and sodium lauryl sulfate as a well-known irritating surfactant. Lauryl ether sulfate served as a substance with high sales volume and good skin tolerance. As was to be expected, lauryl ether sulfate scored only slightly better than lauryl sulfate. Sulfosuccinate values obtained were classified under little skin roughening effect. ... 

The active ingredients in a shampoo play three fundamental roles. Some allow water to wash away the substances that make hair dirty. Others adhere to hair to impart a desirable feel and texture. The rest are emulsifiers that keep the mixture from separating into its components. To accomplish these effects, ingredients combine two types of interactions a strong attraction to water (hydrophilic) and an aversion to water (hydrophobic). It may seem that these properties are incompatible, but shampoos contain molecules that are designed to be simultaneously hydrophilic and hydrophobic. One example is sodium lauryl sulfate, our inset molecule. The ionic head of the molecule is hydrophilic, so it interacts attractively with water. The hydrocarbon tail is hydrophobic, so it interacts attractively with grease and dirt. Molecules of the shampoo associate with hydrophobic dirt particles to form hydrophilic clumps that dissolve in water and wash away. 

Composition of Emulsion, The prototype oil/water emulsion described in Table I contained ingredients typical of a large number of cosmetic products, although simplified somewhat to avoid analytical problems. The aqueous phase contained sodium lauryl sulfate (SLS) as emulsifier, 0,2% (19 n ) DEA as precursor to NDEIA and 0,1% benzoic acid as preservative. 

Melt the stearyl alcohol and white petrolatum (steam bath) and warm to about 75°C. Heat the water to 75°C and add the sodium lauryl sulfate, propylene glycol, methylparaben, and propylparaben. Add the aqueous phase and stir until congealed. IV. Water-soluble ointment (polyethylene glycol ointment, USP 14) Polyethylene glycol 4000 (Carbowax 4000) 50%... 

JR Crison, ND Weiner, GL Amidon. Dissolution media for in vitro testing of water-insoluble drugs Effect of surfactant purity on in vitro dissolution of carbama-zepine in aqueous solutions of sodium lauryl sulfate. J Pharm Sci 86 384-388, 1997. 

Besides the test substance, a positive control substance (a known skin irritant, 1% sodium lauryl sulfate in distilled water) and a negative control (untreated patch) are applied to the skin. When a vehicle is used for diluting, suspending, or moistening the test substance, a vehicle control patch is required, especially if the vehicle is known to cause any toxic dermal reactions or if there is insufficient information about the dermal effects of the vehicle. 

For the purpose of the following discussion, the xenobiotics studied in the dogfish shark were divided into three classes 1) those relatively hydrophilic (Table V) those relatively lipophilic (i.e., solubility in water less than 1 mg/ml, Table VI) and, 3) metal-containing pollutants (Table VII) Most of these data have been previously reported (18-23) using C compound, for assay, with the exception of sodium lauryl sulfate (SLS) ( S), cis-Pt (atomic absorption spectroscopy) and phenol red (spectrophotometry). Unless otherwise stated these data are presented as total radioactivity and the hazards of doing so are recognized (24). 

The liquid chromatographic analysis was carried out using serial 4x300mm u-Bondagel E-125 and E-500 columns obtained from Waters Associates, Inc. The carrier was prepared to contain (A) 0.25M sodium perchlorate, 0.1% sodium lauryl sulfate that was dissolved and brought to pH 7.2 using ammonium phosphate and (B) tetrahydrofuran. An A/B ratio of 9 1 was mixed and filtered through a 0.2um membrane. 

It is noted that these analytical conditions were not problem-free. Period column washing with water and frequent pump dissembly and cleaning were necessary to compensate for column and apparatus fouling that may have been caused by higher molecular weight homologs in the sodium lauryl sulfate additive. 

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. 

Fig. 13. Comparison of effect of sodium lauryl sulfate on the transfer of acetic acid from water to benzene at 25°C. in an unstirred (36, 37), and in a stirred cell (60).

Frankild S, Andersen KE, Nielsen GD. 1995. Effect of sodium lauryl sulfate (SLS) on in vitro percutaneous penetration of water, hydrocortisone and nickel. Contact Dermatitis 32 338-345. 

Surfactants can act like lipids or emulsifiers in solubilizing flavor materials in surfactant micelles. Headspace analysis techniques were used to follow the release of several common dentifrice flavorants from a solution containing the surfactant sodium lauryl sulfate. Water/micelle partition coefficients were derived to describe the solubilization of the flavorants in tiie surfactant micelle (76). Initially, the flavor is solubilized in the surfactant micelle. As both the micelle and flavor concentration decrease on dilution, flavor compounds, which are highly soluble in the micelle, preferentially increase in the headspace [HGURE11]. 

A stirring rate of about 200 rpm should be adequate to keep the monomer dispersed without the formation of a separate monomer layer. Once polymerization is underway, the rate of agitation may not be important as long as no separate monomer layer forms. Once sodium lauryl sulfate has been added to the water, the nitrogen inlet tube must be raised above the liquid level to reduce foam and bubble formation. 

---