Fatty synthetic

A.gllsethionates. These are among the oldest of the synthetic detergents and were developed ia Germany to overcome problems of hard water. They are prepared by reaction of fatty acid chlorides with a salt of isethionic acid, ie, 2-hydroxyethanesulfonic acid [107-36-8]. These detergents have moderate foaming properties and have seen only limited use ia shampoos. 

Interest in synthetic naphthenic acid has grown as the supply of natural product has fluctuated. Oxidation of naphthene-based hydrocarbons has been studied extensively (35—37), but no commercially viable processes are known. Extensive purification schemes must be employed to maximize naphthene content in the feedstock and remove hydroxy acids and nonacidic by-products from the oxidation product. Free-radical addition of carboxylic acids to olefins (38,39) and addition of unsaturated fatty acids to cycloparaffins (40) have also been studied but have not been commercialized. 

Emulsifiers are incorporated in oil and synthetic mud formulations to maintain a stable emulsion of the internal brine phase. These materials include calcium and magnesium soaps of fatty acids and polyamines and amides and their mixtures (123,127). The specific chemistry of these additives depends on the nature of the continuous phase of the mud, ie, whether diesel oil, mineral oil, or a synthetic Hquid. Lime is added along with the fatty acid to form the... 

To overcome these difficulties, drilling fluids are treated with a variety of mud lubricants available from various suppHers. They are mostly general-purpose, low toxicity, nonfluorescent types that are blends of several anionic or nonionic surfactants and products such as glycols and glycerols, fatty acid esters, synthetic hydrocarbons, and vegetable oil derivatives. Extreme pressure lubricants containing sulfurized or sulfonated derivatives of natural fatty acid products or petroleum-base hydrocarbons can be quite toxic to marine life and are rarely used for environmental reasons. Diesel and mineral oils were once used as lubricants at levels of 3 to 10 vol % but this practice has been curtailed significantly for environmental reasons. 

Unsubstituted Amides. The most widely used synthetic route for primary amides is the reaction of fatty acid with anhydrous ammonia (11). Fatty acid and ammonia are allowed to react at approximately 200°C for 10 to 12 h under a constant vent of excess ammonia and water by-product. A pressure of 345—690 kPa (50—100 psi) is maintained by the addition of ammonia while the venting of water faciUtates the completion of the reaction. 

In recent years, especially in the USSR and Europe, synthetic fatty acids, prepared via hydrocarbon oxidation, have been used to prepare fatty amines (2,9). In 1978 Eastern Europeans produced an estimated 0.55 biUion kg of synthetic fatty acids with odd and even numbers of carbon atoms, whereas in the United States, production of natural fatty acids with even carbon atom chain-length acids was 435 million kg. To date, there has been no significant production of synthetic fatty acids in the United States. 

Synthesis and Manufacture of Amines. The chemical and busiaess segments of amines (qv) and quaternaries are so closely linked that it is difficult to consider these separately. The majority of commercially produced amines origiaate from three amine raw materials natural fats and oils, a-olefins, and fatty alcohols. Most large commercial manufacturers of quaternary ammonium compounds are fully back-iategrated to at least one of these three sources of amines. The amines are then used to produce a wide array of commercially available quaternary ammonium compounds. Some iadividual quaternary ammonium compounds can be produced by more than one synthetic route. 

A fermented-egg product (EEP), patented as an attractive bait for synanthropic flies, has been shown to be attractive to coyotes and repeUent to deer (79). Its components are variable, with relative concentrations of 77% fatty acids, 13% bases, and 10% (primarily) neutrals composed of at least 54 volatiles such as ethyl esters, dimethyl disulfide, and 2-mercaptoethanol. Synthetic formulations have been evaluated to find a replacement for a patented fermented-egg protein product that attracts coyotes and repels deer. Ten aUphatic acids (C-2 to C-8), four amines (pentyl, hexyl, heptyl, and trimethyl), dimethyl disulfide, 2-mercaptoethanol, and 54 more volatiles (C-1 to C-5 esters of C-1 to C-8 acids) have been tested as synthetic fermented egg (SEE) (80) in approximately the same proportions that are present in EEP. Weathering was a problem that caused decreased efficacy, which suggests trials of controUed-release formulations. Eourteen repeUents have been examined against white-taU deer in Peimsylvania in choice tests when treated onto sheUed com (81). 

Natural mbber usually contains sufficient levels of naturally occurring fatty acids to solubilize the zinc salt. However, if these fatty acids are first extracted by acetone, the resultant "clean" natural mbber exhibits a much lower state of cure. Therefore, to ensure consistent cure rate, fatty acids are usually added. Synthetic mbbers, especially the solution polymers, do not contain fatty acids and requite thein addition to the cure system. 

Although soaps have many physical properties in common with the broader class of surfactants, they also have several distinguishing factors. First, soaps are most often derived direcdy from natural sources of fats and oils (see Fats and fatty oils). Fats and oils are triglycerides, ie, molecules comprised of a glycerol backbone and three ester-linked fatty oils. Other synthetic surfactants may use fats and oils or petrochemicals as initial building blocks, but generally require additional chemical manipulations such as sulfonation, esterification, sulfation, and amidation. 

Minor ingredients include excess fatty acids, preservatives, and potentially other synthetic surfactants. Alternatively, mixing can be achieved through the use of in-line static mixers, with the accurate addition of the minors into a flowing stream of the wet soap. 

Vatty Acids andFattyAcidLsters. Sulfolane exhibits selective solvency for fatty acids and fatty acid esters which depends on the molecular weight and degree of fatty acid unsaturation (40—42). AppHcations for this process are enriching the unsaturation level in animal and vegetable fatty oHs to provide products with better properties for use in paint, synthetic resins, food products, plastics, and soaps. 

Early waterproofing treatments consisted of coatings of a continuous layer impenetrable by water. Later water-repellent fabrics permitted air and moisture passage to improve the comfort of the wearer. Aluminum and zirconium salts of fatty acids, siUcone polymers, and perfluoro compounds are apphed to synthetic as well as natural fibers. An increase in the contact angle of water on the surface of the fiber results in an increase in water repeUency. Hydrophobic fibers exhibit higher contact angles than ceUulosics but may stiU require a finish (142). 

Carboxylic acids having 6—24 carbon atoms are commonly known as fatty acids. Shorter-chain acids, such as formic, acetic, and propionic acid, are not classified as fatty acids and are produced synthetically from petroleum sources (see Acetic acid Formic acid and derivatives Oxo process). Fatty acids are produced primarily from natural fats and oils through a series of unit operations. Clay bleaching and acid washing are sometimes also included with the above operations in the manufacture of fatty acids for the removal of impurities prior to subsequent processing. 

Synthetic Routes to Fatty Acids from Petroleum... 

Catalytic Oxidation for Straight-Chain Paraffinic Hydrocarbons. Synthetic fatty acids (SFA) are produced by Eastern European countries, Russia, and China using a manganese-catalyzed oxidation of selected paraffinic streams. The technology is based on German developments that were in use during World War II. The production volume in 1984 was estimated to be about 5.5 x ICf t/yr. The oxidation is highly exothermic and is carried out at about 105—125°C, mostly in continuous equipment. 

Cobalt in Driers for Paints, Inks, and Varnishes. The cobalt soaps, eg, the oleate, naphthenate, resinate, Hnoleate, ethyUiexanoate, synthetic tertiary neodecanoate, and tall oils, are used to accelerate the natural drying process of unsaturated oils such as linseed oil and soybean oil. These oils are esters of unsaturated fatty acids and contain acids such as oleic, linoleic, and eleostearic. On exposure to air for several days a film of the acids convert from Hquid to soHd form by oxidative polymeri2ation. The incorporation of oil-soluble cobalt salts effects this drying process in hours instead of days. Soaps of manganese, lead, cerium, and vanadium are also used as driers, but none are as effective as cobalt (see Drying). 

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. 

Adsorption. Many studies have been made of the adsorption of soaps and synthetic surfactants on fibers in an attempt to relate detergency behavior to adsorption effects. Relatively fewer studies have been made of the adsorption of surfactants by soils (57). Plots of the adsorption of sodium soaps by a series of carbon blacks and charcoals show that the fatty acid and the alkaU are adsorbed independently, within limits, although the presence of excess aLkaU reduces the sorption of total fatty acids (58). No straightforward relationship was noted between detergency and adsorption. 

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