Fatty-acid soaps characteristics

A fatty acid soap in which a polyglycol ether group has been introduced between the fatty chain and the carboxylic group, which transforms some unfavorable properties of soaps into positive characteristics without decreasing the overall positive effects, and... 

Fatty-acid soaps have some inherent characteristics which make them more acceptable as a means of reducing compound viscosity than do chemical peptizers. Because of their fatty-acid soap base they could eliminate or reduce the need for added fatty acid activators, and considerably reduce the stickiness of low-viscosity natural rubber masterbatches. They can be used in a number of applications where conventional chemical peptizers could cause contamination problems, e.g. in the food industry. They must, however, be used in considerably higher dosages than chemical peptizers. 

The solubihty characteristics of sodium acyl isethionates allow them to be used in synthetic detergent (syndet) bars. Complex blends of an isethionate and various soaps, free fatty acids, and small amounts of other surfactants reportedly are essentially nonirritant skin cleansers (66). As a rule, the more detersive surfactants, for example alkyl sulfates, a-olefin sulfonates, and alkylaryl sulfonates, are used in limited amounts in skin cleansers. Most skin cleansers are compounded to leave an emollient residue on the skin after rinsing with water. Free fatty acids, alkyl betaines, and some compatible cationic or quaternary compounds have been found to be especially useful. A mildly acidic environment on the skin helps control the growth of resident microbial species. Detergent-based skin cleansers can be formulated with abrasives to remove scaly or hard-to-remove materials from the skin. 

Properties are furthermore determined by the nature of the organic acid, the type of metal and its concentration, the presence of solvent and additives, and the method of manufacture. Higher melting points are characteristics of soaps made of high molecular-weight, straight-chain, saturated fatty acids. Branched-chain unsaturated fatty acids form soaps with lower melting points. Table 1 Hsts the properties of some soHd metal soaps. 

In positive ion mode, the characteristic peaks representative of the binding media were fatty acids from lead soaps (of palmitic acid at m/z 461 463 and of stearic acid at m/z 489 491). Other peaks corresponding to mono- and diacylglycerol cations, protonated stearic acid or its acylium ions could be found in the spectra of the reference products but not in the paint sample. The spectrum of lead white egg tempera paint exhibits peaks of phosphocholine (m/z 184) and protonated ketocholesterol (m/z 401). These peaks were not found in the spectrum from the cross-section. In negative ion mode, the spectrum of the oil... 

Damp-proofing admixtures include soaps and fatty acids which react with the cement hydrates to modify workability, bleeding and settlement, air content, compressive strength and durability characteristics. Mix proportions, mix consistency, admixture dosage and poor mixing influence the effects produced by the admixture. In cement-rich mixes void content is often increased, resulting in increased permeability. Since the admixture... 

Nor are those in phase 2 free of 5.8- to 5.9-micron absorbing material. The latter peak is characteristic of both free fatty acid and phase 1 acid-soap. Hence, this does not allow a definitive statement of the second species present. It is, however, likely to be phase 1 (or 3) material since the DTA results point to the absence of free fatty acid in most cases. Furthermore, acid-soap in one phase can transform to another phase as has been clearly demonstrated. 

Snap. A critical ingredient for emulsion polymerization is the soap, which performs a number of key roles, including production of oil (monomer) m water emulsion, provision of the loci for polymerization (micelle), stabilization of the latex particle, and imputation of characteristics to the finished polymer. Both fatty acid and rosin acid soaps, mamly derived from tall oil, are used in ESBR,... 

Many anionic surfactants can react with a cationic dye such as methylene blue to form strong ion pairs that can be extracted by a suitable organic solvent and can be determined using colorimetric techniques. The anionic surfactants that respond to the methylene blue test are primarily the sulfonate (RS03 Na+) and the sulfate ester (R0S03 Na+) type substances. On the other hand, soaps and the alkali salts of fatty acids (C-10 to C-20) used in certain detergents do not respond to the above test. The various anionic surfactants and their characteristic structural features are presented in Figure 2.32.1. 

An amber-yellow coloured oil with a pleasant characteristic odour. Particularly suited to greasy complexions as it rapidly penetrates the skin, having an astringent and circulatory stimulating effect in addition to its nutritive properties. When diluted with other carriers like sunflower or grapeseed the blend may benefit conditions like acne. Cosmetically hazelnut oil is used in sun filter lotions and creams, soaps, shampoos and other hair products. Its main fatty acids are oleic (70-84%), linoleic (9-19%) and stearic (1-4%). It has been reported to cause immunological urticaria (a skin condition also known as hives) and in common with other nut oils there is a possibility of anaphylactic shock. 

Lanthanides react with fatty acids such as lauric, palmitic and stearic acids to give compounds of the formula Ln(COOR)3. Lanthanide alkoxides react with fatty acids to yield mixed ligand soaps, [Ln(OR)A ], where A is a fatty acid. Reaction of [Ln(OR)A ] with acetyl chloride or acetyl bromide yield lanthanide chloride- or bromide-mixed soaps. The spectral characteristics of the alkoxide-mixed soaps, chloride-mixed soaps, bromide-mixed soaps and quaternary-mixed soaps of Pr(III) and Nd(III) were studied and the spectral parameters were evaluated by regression analysis. The intensification of the bands and the nephelauxetic effect were in the order quaternary soaps > alkoxide soaps > chloride-bromide-mixed soaps. The above order is in agreement with the calculated covalency due to the lowering of coulombic interaction parameters as well as the lower melting points of the mixed soaps. 

Solubility differences of fatty acid salts In 1828, Gusserow introduced a method that lead salts or soaps of fatty acids in ether can be separated depending on the solubility differences. Saturated and unsaturated fatty acids form salts with metallic ions (e.g., Li) whose solubihties in water and organic solvents vary with the nature of the metallic ion and the chain length, degree of unsaturation, and other characteristics of the acid radicals. Substitution of ethanol for diethyl ether (113) allows better separation. 

Raw and acidulated RBL are combined in dilferent ratios with animal tallow to produce soaps of varying characteristics. Palm oil and coconut oil are the dominant fatty acid sources for soap manufacturing. Coconut oil and tallow are complementary in fatty acid composition such that in combination they provide the ingredients of toilet soap (96). There has been speculation regarding the use of safflower and sunflower RBL in this capacity if alterations were made to processing methods. Cottonseed and soybean RBLs are available in large quantities but the cost of upgrading these to the quality necessary for use in toilet soap inhibits their use. 

The major use of rendered fats is in the production of tallow soaps and in the area of fat hydrolysis, sphtting triglycerides into fatty acids, and byproduct glycerine. As the soap-making industry grew and became more refined, the quality standards and specifications for animal fat became more precise to meet the soap industry s need. The specihcations and terminology, from the soap industry, form the basis for the quality standards and characteristics used today. 

Official methods of chemical analysis of conventional diesel are often not adequate to characterize biodiesel. Tests for the levels of sulfur and aromatic components in biodiesel are useful but usually reveal that the concentrations of compounds containing these atoms or functional groups are very low. Analysis of biodiesel chemistry can reveal characteristics conferred by the source of the oU, the method of manufacture, and duration of storage (20, 21). For example, free and bound glycerol is measured to ascertain if biodiesel has been completely formed during synthesis. Fatty acid content, residual soaps, iodine value, peroxide value, and fatty acid composition all may reflect the quality of biodiesel (Table 1) but are unimportant and inapplicable in conventional diesel fuel quality determination. 

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