Long-chain soaps

Consider using long chain soaps for apphcations at temperatures > 60°C, and shorter chains (C12-C14) for application at low temperatures. Use in a mixture with ethoxylated fatty alcohols to enhance efficiency. 

In the field of synthetic polyelectrolytes, the special case of polysoaps (defined as synthetic polymers into which long chain soap-like groups have been introduced) was extensively studied [2]. Their compact conformation was shown to be primarly due to strong apolar-apolar interactions between the long aliphatic side groups carried by the main chain. 

Clearly, long-chain soaps and fatty acids are likely to form calcium soap antifoams even in the presence of large amounts of sodium tripolyphosphate builder. However, if builders with complexation constants significantly lower than those of sodium tripolyphosphate are used, then it is possible that calcium soap formation may be inhibited and antifoam effects diminished. Observations of Schmadel and Kurzendorfer [5] comparing the antifoam effect of soaps in the presence of nitrilotri-acetic acid and sodium tripolyphosphate are consistent with that expectation. 

The phase changes during the hydration process involve the dissolution of the eta type solid-phase phases to form additional liquid crystal and solution phases. The less soluble kappa phases that contain longer chain soaps also dissolve and the long chain soaps then reprecipitate as insoluble solids. These solids along with the liquid crystalline phases are responsible for the mush layer which forms on the bar surface. 

Fatty acids and their alkali salts (soaps) [45,53,54] have been used for a long time. Their efficacy is influenced by water hardness and the builder s system of the laundry-washing product. The chain length of the fatty acid determines the efficacy of soap as an antifoam as a function of the water temperature. Long-chain soaps are effective at high temperatures (>60°C) shorter chains (C12-C14) are effective at low water temperatures. 

Ester hydrolysis in base is called saponification, which means soap making Over 2000 years ago the Phoenicians made soap by heating animal fat with wood ashes Animal fat is rich m glycerol triesters and wood ashes are a source of potassium car bonate Basic hydrolysis of the fats produced a mixture of long chain carboxylic acids as their potassium salts... 

Fats and oils are one of the oldest classes of chemical compounds used by humans. Animal fats were prized for edibiUty, candles, lamp oils, and conversion to soap. Fats and oils are composed primarily of triglycerides (1), esters of glycerol and fatty acids. However, some oils such as sperm whale (1), jojoba (2), and orange roughy (3) are largely composed of wax esters (2). Waxes (qv) are esters of fatty acids with long-chain aUphatic alcohols, sterols, tocopherols, or similar materials. 

Reaction with Fatty Acids and Esters. Alkanolamines and long-chain fatty acids react at room temperature to give neutral alkanolamine soaps, which are waxy, noncrystaUine materials with widespread commercial appHcations as emulsifiers. At elevated temperatures, 140 —160°C, A/-aIkanolamides are the main products, at a 1 1 reaction ratio (7,8). 

Release agents function by either lessening intermolecular interactions between the two surfaces in contact or preventing such close contact. Thus, they can be low surface-tension materials based on aUphatic hydrocarbon, fluorocarbon groups, or particulate soHds. The principal categories of material used are waxes, fatty acid metal soaps, other long-chain alkyl derivatives, polymers, and fluorinated compounds. 

Emulsion Polymerization. In this method, polymerization is initiated by a water-soluble catalyst, eg, a persulfate or a redox system, within the micelles formed by an emulsifying agent (11). The choice of the emulsifier is important because acrylates are readily hydrolyzed under basic conditions (11). As a consequence, the commonly used salts of fatty acids (soaps) are preferably substituted by salts of long-chain sulfonic acids, since they operate well under neutral and acid conditions (12). After polymerization is complete the excess monomer is steam-stripped, and the polymer is coagulated with a salt solution the cmmbs are washed, dried, and finally baled. 

Hydrolysis of animal fats in the presence of strong base leads to glycerol and salts of long-chain carboxylic acids. The latter are known as soaps . 

The catalytic oxidation of long-chain paraffins (C18-C30) over manganese salts produces a mixture of fatty acids with different chain lengths. Temperature and pressure ranges of 105-120°C and 15-60 atmospheres are used. About 60 wt% yield of fatty acids in the range of C12-C14 is obtained. These acids are used for making soaps. The main source for fatty acids for soap manufacture, however, is the hydrolysis of fats and oils (a nonpetroleum source). Oxidation of paraffins to fatty acids may be illustrated as ... 

Soaps act as cleansers because the two ends of a soap molecule are so different. The carboxylate end of the long-chain molecule is ionic and therefore hydrophilic (Section 2.13), or attracted to w ater. The long hydrocarbon portion of the molecule, however, is nonpolar and hydrophobic, avoiding water and therefore more soluble in oils. The net effect of these tw O opposing tendencies is that soaps are attracted to both oils and water and are therefore useful as cleansers. 

Stearic acid is the most common of the long-chain fatty acids. It is found in many foods, such as beef fat and cocoa butter. It is widely used as a lubricant in soaps, cosmetics, food packaging, deodorant sticks, and toothpastes. It is also a commonly used softener in rubber. 

The development of alkylbenzenesulfonates (ABSs) goes back to 1923, when the British chemist Adams discovered that it was possible to obtain water-soluble products by the sulfonation and neutralization of hexadecyl- and octadecyl-benzene. Such products have also soap-like characteristics [1]. In 1926 IG-Farbenindustrie (Hoechst) and Chemische Fabrik Pott, Pirna/Sachsen simultaneously discovered that long-chain ABSs have excellent surface-active properties. 

The cleaning action of soaps and detergents relies on the like-dissolves-like rule. Soaps are the sodium salts of long-chain carboxylic acids, including sodium stearate (3). 

Lithium compounds are used in ceramics, lubricants, and medicine. Small daily doses of lithium carbonate are an effective treatment for bipolar (manic-depressive) disorder but scientists still do not fully understand why. Lithium soaps—the lithium salts of long-chain carboxylic acids—are used as thickeners in lubricating greases for high-temperature applications because they have higher melting points than more conventional sodium and potassium soaps. 

The alkaline product from the wood ash was a crude solution of sodium and potassium carbonates called "lye". On boiling the vegetable oil with the lye, the soap (sodium and potassium salts of long chained fatty acids) separated from the lye due to the dispersive interactions between the of the fatty acid alkane chains and were thus, called "lyophobic". It follows that "lyophobic", from a physical chemical point of view, would be the same as "hydrophobic", and interactions between hydrophobic and lyophobic materials are dominantly dispersive. The other product of the soap making industry was glycerol which remained in the lye and was consequently, termed "lyophilic". Thus, glycerol mixes with water because of its many hydroxyl groups and is very polar and hence a "hydrophilic" or "lyophilic" substance. 

A few of the important reactions carboxylic acids undergo are shown above. Soap is made by reacting sodium or potassium hydroxide with long-chain acids such as C17H35COOH (stearic acid). Acid chlorides and acid anhydrides are more reactive than their corresponding carboxylic acids and are used in the chemical industry to make various acid derivatives. A very important industrial reaction is the reaction of carboxylic acids (or the chlorides or anhydrides) with alcohols to form esters. 

Sodium carbonate is an alkali, a strongly basic compound that has a pH of 9 or more in solution. Boiling an alkali with fat makes soap. Chemically, soap contains a long chain of hydrocarbons that repels water but has an affinity for other fatty substances. When treated with alkali, the ends of the fatty chains are modified so that they are attracted to water. A molecule with one end that attracts fatty substances and another end that likes to dissolve in water is ideal for coating dirt particles and floating them away in water. Soap can be made from any kind of fat, whether from kitchen scraps or whale, olive, or palm oil. 

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