Soap ratio, alcohol

For soap/alcohol combinations — g will depend not only on the soap counter ion but also on the alcohol/soap ratio. Furthermore, when a certain alcohol/soap ratio is exceeded (=2 for the potassium oleate system) S becomes Independent of the water content of the lamellar phase. This condition applies for Inverse structures and the water/pentanol/potassium oleate inverse micellar system will be examined for the structure determining ratio in Table I. 

The o c experimental results for the water/pentanol/potas-slum oleate system (18,19) show that a pentanol/potasslum oleate molecular ratio of 5.5 and lower should give a premlcellar aggregate/lamellar liquid crystal transition instead of the pre-micellar aggregate/Inverse micelle transition at high alcohol/ soap ratios. 

The destabilization of the premlcellar aggregates at high water content may give rise to a) separation of liquid water, b) formation of Inverse micelles, or c) separation of a lamellar liquid crystal. Approximate calculations using the Tanford-Nlnham approach gave correct Information for a model system, but the critical ratio appeared too Insensitive to the alcohol/soap ratio to be useful. 

The enhanced water solubihty, on the other hand, is caused by the existence of inverse micelles. The maximum size of these to allow maximum water solubilization depends critically on the alcohol/soap ratio in Figure lb maximum water solubility is obtained at a weight ratio of 5 2. 

Identical conditions exist if the corresponding solubility region is determined at constant hydrocarbon content in a microemulsion. Such compositions mean that a fourth component is introduced, and a tetrahedral representation is necessary such as in Figures 2a, b, and c. From this and other diagrams (8,9,10) an important conclusion concerning microemulsion conditions may be drawn— the alcohol/soap ratio necessary to obtain maximum water solubihzation remains identical at different hydrocarbon contents. 

Wherever possible, the soaps and surfactants were added to the natural rubber latex as dilute aqueous solutions. The cases where this was not possible were (a) ethylene oxide-fatty alcohol condensates of low ethylene oxide fatty alcohol mole ratio, and (b) sparingly-soluble fatty-acid soaps such as lithium laurate and calcium soaps. The former were added as pastes with water, the latter as dry powders. In all cases, the latex samples were allowed to mature for about three days at room temperature before their mechanical stabilities were determined. This allowed some opportunity for the attainment of adsorption equilibrium. 

The mean polar head group area in a water/decanol/potassium oleate system is approximately 26 A for an alcohol/soap molecular ratio of 2.l — For the soap alone an area of 36.0 3 was found. Assuming a linear relationship a value of 22 A is obtained for the decanol. This value will be used also for the pentanol. The volume, chain length and area can now be estimated ... 

Fig. 7. Relative intensities versus volume fraction (() for microemulsions relative to the same water/soap ratio but to different kinds of oil and alcohol.

Fig. 9. Influence of water/soap ratio and of oil and alcohol nature on diffusion coefficient.

Fig, 11. Comparative conductive behavior of water-in-hexadecane systems using potassium oleate as the surfactant and either 1-pentanol or 1-hexanol. Soap to alcohol mass ratio equal to 3/5. Combined soap and alcohol mass fraction p equal to 0.40. represents the water volume fraction. Temperature T = 25°C. 

It can be synthesized by reaction of a 1 1 molar ratio of ethyl vinyl ether and phenethyl alcohol in the presence of cation exchange resin [141]. It imparts fresh, floral, green notes and is used in fine fragrances as well as in soap, cosmetics and detergents. 

The composition data obtained for the series of mixed fatty acid-potassium soap systems, prepared by both the ethanol and petroleum ether routes, lend strong support to the formation of 1 to 1 acid-soap complexes. It is of interest to inquire into the phase relationships in these two-component systems. A phase diagram presented by McBain and Field (15) for the lauric acid-potassium laurate system shows that compound formation takes place between the two components at the 1 to 1 molar ratio, but the compound undergoes melting with decomposition at 91.3 °C. [A similar type of phase behavior has been reported by us for the sodium alkyl sulfate-alkyl alcohol (9) and sodium alkyl sulfonate-alkyl alcohol (12) systems, but in these cases the stoichiometry is 2 to 1]. 

This can be prepared in several different ways. Commonly dry Castile soap is dissolved in 80 per cent, alcohol in such proportions as will yield a solution well above the desired final concentration 100 grams per litre is a convenient ratio. After allowing this solution to stand at rest for several days for the deposition of undissolved matter, a quantity of the clear liquid is withdrawn (usually 75-100 c.c. per litre of final solution), and so diluted with 80 per cent, alcohol as to produce a solution which on titration with a known weight of calcium chloride solution under the standard conditions will give results in accordance with Clark s table. The calcium chloride solution is best prepared by dissolving 0-2 grams of Iceland spar in dilute hydrochloric acid excess of acid is removed by evaporation on a water bath and the solution then diluted to 1 litre with distilled water. A mixture of 25 c.c. of this solution, mixed with 25 c.c. of water, should require 7-8 e.e. of Clark s standard solution for the production of a permanent lather. 

The difference is pronounced. In an alcohol solution a minimum of approximately six water molecules are required per soap to bring it into solution. A liquid carboxylic acid will dissolve the soap without water to a soap/acld molecular ratio of 1/2. It appears reasonable to evaluate these differences from terms of intermolecular forces. These forces, the strong hydrogen bonds and ligand bonds to the metal ion will be treated in the following section. 

The results showed distinct and regular changes for the aqueous solubility region in pentanol surfactant mixtures. With increased electrolyte content, the "minimum amount of water for solubility was enhanced, the solubility limit towards the pentanol water axis was shifted to higher soap concentrations, and the "maximum solubility of the aqueous sodium chloride solution was obtained for higher surfactant alcohol ratios (Figure 2). 

The shift of the solubility limit against the pentanol water axis (Figure 2, left) towards higher concentration of soap with an added electrolyte is mainly related to the solubility of the water in pentanol. The solubility of the aqueous solution in pentanol is reduced with increasing sodium chloride concentration this fact accounts for the lowering of solubility at low surfactant alcohol ratios. 

However, since many natural oils and absolutes also possess a correspondingly high odour strength and quality, the ratio of the cost to strength and quality should always be considered carefully before removing them. In this case, it is difficult to justify inclusion of the broom absolute in the soap context, so in its place a small quantity of methyl anthranilate (the chemical that quantitatively dominated the headspace of broom) is added. Care should always be taken with anthranilates because of the possible formation of Schiff s bases upon reaction with aldehydes. Extra aldehydes will certainly be added to the soap version of the alcoholic perfume because of their excellent odour performance in covering the fatty smell of common soap bases. 

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