Anhydrous soaps

Drymet . [Crosfield Rhone-Poulenc Basic] Sodium metasilicate anhydrous soap builder and detergent for formulating industrial cleaners aids buffering capacity and corrosion inhibition of soft metals and ceramic glazes. 

Phases with noncubic structures were first identified by X-ray scattering from aqueous soap mixtures [68, 69] and anhydrous soap melts in a series of papers by Luzzati and Skoulios [69-73]. In the first of these papers [68] the term intermediate was applied to a rectangular structure found in aqueous mixtures of potassium and sodium oleates and potassium laurate and pal-mitate. The structures found in the anhydrous soaps were reinterpreted as intermediate, tetragonal, rhombohedral, and ribbon structures in the paper by Luzzati and coworkers [74] in 1968. It was not until the early eighties that interest in these unusual phase structures was rekindled. 

The first identification of intermediate mesh phase structures was by Luzzati [74] from the measurements by Spegt and Skoulios [70-73] in anhydrous soap melts. It was not until the work of Kekicheff and others [62, 76-81] on sodium dodecyl sulfate (SDS)/water and on lithium perfluoroocta-... 

The ARMOUR process (Ladyn, 1964) uses a De Laval column to neutralize fatty acids while Alfa Laval have developed their own system where again a De Laval column is used with concentrated (50%) sodium hydroxide to produce an 86% anhydrous soap which therefore requires no drying step, a considerable process improvement. 

For more than two thousand years liquid-crystalline phases of soaps have been used for cleaning. The physical structure of these phases was revealed only recently. This was mainly due to the opinion that soap molecules should be regarded as rigid rods. In an infrared absorption spectroscopy study of anhydrous soaps, Chapman (1958) concluded that a high-temperature phase transition was caused by melting of the chains. Later Luzzati and co-workers (1960) conclusively demonstrated the liquid nature of the hydrocarbon chains as a fundamental feature in the structure of liquid-crystalline phases. They were also able to determine the structures of the most common liquid-crystalline phases. 

The sample of silicate of soda contained, therefore, 2 per cent, of anhydrous soap, but as such a solution... 

Sodium linear alkylbenzene sulfonate Anhydrous soap... 

Sodium cocoyl isethionate Sodium alkylbenzene sulfonate Anhydrous soap Sodium isethionate Stearic acid Sodium sulfate... 

A substantial amount of work has been carried out on thermotropic transitions of anhydrous soaps and other surfactants using high-temperature XRD and NMR. The mobility of the hydrocarbon chains increases with temperature, which leads to the formation of mobile solid phases (waxy phases) and liquid aystalline phases [27-29], These transitions have very limited application in cleansing products. Some of these transitions take place during processing of soap at elevated temperatures. 

Anhydrous Soap The physical properties of anhydrous soaps are varied. The hydrocarbon chains crystaUize and form a solid at ambient temperature. A bilayer structure is normally formed from alkaline soap with the hydrocarbon chains orienting perpendicular... 

Anhydrous Soap Content a soap sample dissolved in a mixed solvent of ethanol and water is treated with mineral acids. The liberated fatty acid reacts with sodium hydroxide solution to form soap. The resulting soap is dried and weighed to establish the anhydrous soap content of the original sample. 

Total and Free Fatty Acids. The total fatty acids are determined by extraction as given above for the method of determination of soap in pharmaceutical preparations. For an oleic acid soap, the fatty acids X 0 968 (to correct for the water formed by combination) plus the combined alkali will give the percentage of anhydrous soap. For an olive oil soap, the error involved by calculating the fatty acids as oleic acid would be negligible. 

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