Alkali metal stearates

Newer polyacrylate rubbers can be cured with certain amines and are more responsive to a broad range of curative systems, e.g., alkali metal stearate/sulphur or sulphur donor, methyl zimate and ammonium adipate. 

Sears and Schulman (51) measured surface pressures and potentials vs. molecular area (20 to 110 sq. A. per molecule) for the alkali metal stearates over 0.5N solutions of LiOH, NaOH, and KOH. Like Adam and Miller, they detected a specific cation effect on the 7r-A and AV-A isotherms of the ionized monolayer at high pH the ir-A curves were expanded in the order of the crystalline sizes of the alkali metal cations K > Na > Li. The sequence is the reverse observed for the long-chain... 

Ibid, Emulsion Type Explosive Composition Containing Ammonium Stearate or Alkali Metal Stearate , U P 3770522 (1973) CA 80, 49974 (1974) 4) Merck (1976), 75 (No 584)... 

Differential scanning calorimetry was used by Murrill and co-workers (43-45) to elucidate solid - solid phase transitions in a large number of organic compounds. First-order transitions were reported for tetrahedral compounds of the type CR1R2R2R4, where R is methyl, methylol, amino, nitro, and carboxy, as well as for octahedral-type compounds. This technique was also used to detect phase transitions in alkali metal stearates (46), some dibenzazepines, carbazoles, and phenothiazines (16), and the half esters of O-phthalic acid (31). The solid-state decomposition kinetics and activation parameters of N-aryl-N -tosyl-oxydt-imide N-oxides were determined using DSC by Dorko et al. (49). 

The phenomenon of a substantial increase in the seleetivity (S) and conversion (C) of the ethylbenzene oxidation to the to a-phenyl ethyl hydroperoxide upon addition of PhOH together with alkali metal stearate M St (NT = Li, Na) as ligands to metal complexes NiII(acac)2 was discovered in our works [1, 2, 4]. 

L = N-metylpyrrolidone-2 (MP), hexamethylphosphorotriamide (HMPA) or alkali metal stearate MSt (M = Li, Na)) seems to be associated with the formation of supramolecular structures due to intermolecular hydrogen bonds. 

Anionic surfactants are negatively charged in an aqueous solution (i.e., -COO-, -OSOj), and widely used because of their cost and performance. Sodium lauryl sulfate, the main component of which is sodium dodecyl sulfate, is highly soluble in water and commonly used to form oil-in-water (O/W) emulsions. Reacting an alkali hydroxide with a fatty acid (e.g., oleic acid) can produce alkali metal soaps (e.g., sodium oleate). Careful attention must be paid to the pH of the dispersion medium and the presence of multivalent metals (see Section 4.2.5). Alkali earth metal soaps (e.g., calcium oleate) produce stable water-in-oil (W/O) emulsions because of their low water solubility and are produced by reacting oleic acid with calcium hydroxide. Triethanolamine stearate produces stable O/W emulsions in situ by reacting triethanolamine in aqueous solution with melted stearic acid at approximately 65°C (e.g., vanishing cream). 

As commercially made by the saponification of fats, soaps are not pure chemical individuals but consist of a mixture of the alkali-metal salts of the several fatty acids contained as esters in the original fat or oil. The composition of soap, therefore, depends upon the composition of the fat from which it is made. As the common fats and oils which are used for this purpose contain, mostly the glycerol esters of palmitic, stearic and oleic acids, the common soaps are mixtures of sodium, or potassium, palmitate, stearate and oleate. We shall consider now,... 

Hydrogenated castor oil retains the hydroxyl group. Its lithium and other alkali metal soaps are outstanding thickeners, providing a gel structure important to the multipurpose greases that are used for automotive, truck, aviation, railroad, and industrial applications. Insolubility of the hydroxyl stearic soap is the key to the formation of a stable and diuable gel strueture. Castor oil is also often used in cosmeties as simple esters, mono- and diglyeerides, glycol esters, and hydroxyl stearates. 

The word soap is used technically to refer to any salt in which the negative ion contains the carboxylate group, —COO", and a long hydrocarbon chain. Thus, sodium stearate is a soap, but sodium lauryl sulfate is not it is a nonsoap detergent or synthetic detergent. Carboxylate salts of metals other than the alkali metals are usually only slightly soluble in water, and therefore not useful as detergents, but they are nevertheless called soaps. Some of them find industrial application as... 

Fatty-acid soaps Alkali, alkaline earth, and other metal soaps sodium stearate aluminum stearate Gear oils paper stock paper sizing glue solutions... 

Aluminum Stearate (or Aluminum tristearate). Al(C18H3502)(Ref2), Al(Cl8H3s02)1>5 (Ref 3), A1(C18H3502)3 (Refs 1 6) mw 313.51 to 877.35 white powder mp 115°, 117—20°(separate values) d 1.065g/cc at 30° (specific gravity 1.070). Sol in alkali, petr, turpentine oil insol in ethanol, ether and w. Forms a gel with aliphatic and aromatic hydrocarbons. Prepn is by reaction in an aq soln of A1 hydroxide, A1 or activated (with Hg chloride in methanol) A1 metal with stearic acid or Na stearate. The reaction product is filtered and dried. CA Registry No [637-12-7]... 

Fatty adds are predominantly used as intermediates. Main applieations are water soluble soaps for household eleaning, personal care, industrial and institutional (I I) cleaning and synthetic rubber manufacturing by emulsion polymerization. Soaps are made by reaction of fatty acids with caustic alkalis, alkali carbonate or ammonia or (>90%) by direct saponification of the triglyceride oil. Another important group of fatty add soaps are dry, water-insoluble metal soaps used as lubricants or stabilizers for PVC and other plastics and aqueous calcium stearate dispersions applied as paper coating... 

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