Fatty acids soap production

Three generations of latices as characterized by the type of surfactant used in manufacture have been defined (53). The first generation includes latices made with conventional (/) anionic surfactants like fatty acid soaps, alkyl carboxylates, alkyl sulfates, and alkyl sulfonates (54) (2) nonionic surfactants like poly(ethylene oxide) or poly(vinyl alcohol) used to improve freeze—thaw and shear stabiUty and (J) cationic surfactants like amines, nitriles, and other nitrogen bases, rarely used because of incompatibiUty problems. Portiand cement latex modifiers are one example where cationic surfactants are used. Anionic surfactants yield smaller particles than nonionic surfactants (55). Often a combination of anionic surfactants or anionic and nonionic surfactants are used to provide improved stabiUty. The stabilizing abiUty of anionic fatty acid soaps diminishes at lower pH as the soaps revert to their acids. First-generation latices also suffer from the presence of soap on the polymer particles at the end of the polymerization. Steam and vacuum stripping methods are often used to remove the soap and unreacted monomer from the final product (56). 

Cosmetics and Personal Care Products. Alkanolamines ate important taw materials in the manufacture of creams (95—97), lotions, shampoos, soaps, and cosmetics. Soaps (98) formed from triethanolamine and fatty acids ate mild, with low alkalinity and excellent detergency. Triethanolamine lauryl sulfate is a common base for shampoos (99—101) and offers significant mildness over sodiumlauryl sulfate. Diethanolamine lauryl sulfate and fatty acid soaps of mono- and trietban olamine can also be used in shampoos and bubble bath formulations. Chemistry similar to that used in soluble oils and other emulsifiers is appUcable to cleansing creams and lotions (102,103). Alkanolamides or salts ate added to the shampoo base to give a smooth, dense foam (104). 

Emulsions. The fatty acid soaps of alkanolamines ate excellent emulsification agents for use in such products as floor poHshes, cosmetics, and functional fluids such as hydrauhc and metalworking fluids. For example, improved hardwater stabiUty of a hydrauhc fluid emulsion is obtained using AMP in the formulation (12). 

Soap Bars. In soap bars the primary surfactant is predominantly sodium salts of fatty acids. These products typically contain between 70 and 85% soap. Occasionally, potassium soap ( 5-30%) is included in the formulation to increase the solubiUty of the soap and, hence, the bar s lathering properties. The low Krafft temperatures for potassium soap are the basis for the lather enhancement, but also limits their content in bars. 

An emulsified fatty acid soap (e.g., magnesium or iron tallate, having between 8 and 18% metal content. This type of product is cationic and may exhibit some partial solubility in both oil and water. It can be fed by pump (usually a progressive cavity pump or a screw pump). 

Because of improved mildness and lime soap dispersing properties ether carboxylates are also used in fatty acid soap-containing products like soap bars and liquid soaps [57,62] a foam improvement in hard water takes place. 

The use of AOS in toiletries and personal care products has now been established. In India, for example, AOS has been used by leading toilet soap manufacturers with clear performance benefits, especially in hard water-sensitive areas. Combo bars, where part of the usual fatty acid soap is replaced by synthetic AOS as shown in Table 29, seem to be especially attractive from a cost/performance point of view. 

Several decades ago, metal salts of fatty acids—soaps—were the most common anionic surfactants. Due to lots of disadvantages (irritation potential, lime soap, etc.) and the rise of petrochemical industry, the market for soaps dropped down with the exception of the field of body cleaning [1]. Today either surfactants based on petrochemical or natural products can be found in the market. 

Surfactant Fatty acid soaps Emulsification of product... 

Principal use of these products as detergents occurred during World War II when they were used with fatty acid soaps in formulating army all-purpose detergent bars (25). Their low molecular weight and high water solubility limited their value for use alone in efficient detergent formulations. 

Glycerine is a byproduct that usually remains with the hnal product. The typical composition of the product consists of 80-85% alkanolamide, 5-7% or less free amine, and traces of fatty acid soap and other byproducts. 

Water-in-oil emulsions traditionally contain surfactants of natural origin such as cholesterol, wool fat, wool alcohols, lanolin, divalent salts of fatty acids soaps, calcium oleate and/or synthetic agents of low hydrophilic-lipophilic balance (HLB) (indicating high lipophilicity), such as Spans (fatty acid esters of sorbi-tan). An example of such a product is Oily Cream B.P. which consists of a 1 1 mixture of wool alcohols and water. 

The third aspect of improvement may mean an entirely different process for making an old substance. For many decades soap has been manufactured by caustic soda saponification of fats in the batch process. In recent years plants have been installed for the high pressure, high temperature rapid hydrolysis of fats in the countercurrent liquid mixed phase using water and a catalyst. In this case the sodium fatty acid or the soap may be prepared by neutralizing the free fatty acid hydrolysis product with caustic soda or soda ash depending upon convenience and the market. Naturally the unit consumption factors changed when the improved process was used. 

The use of builders in liquid laundry formulations has effectively been restricted to citrates and fatty acid soaps (in isotropic compositions sold in the U.S. and Europe). Although liquid laundry products can contain tripolyphosphate, soda ash, NTA, and other common builders found in powder laundry, limitations on solubility (in a surfactant matrix) or regulatory concerns have restricted their utilization. There is a finite number of patents covering zeolite-built HDLDs, but problems... 

Those fata taken in with the food are unaltered by the digestive fluids, except in that they are freed from tiieir enclosing membranes in the stoniAcb, until they reach the duodenum here, under the influence of the pancreatic juice, the major port is converted into a fine emulsion, in which form it is absorbed by the ueteals. A smaller portion ia saponified, and the products of the saponification, free fatty acids, soaps, and glycerin. Sub uentiy absorbed ig lacteals and blood-vessels. 

Fatty acids are used in various industrial applications in the form of the free acid or as derivatives such as soaps, esters, alcohols, or amides. End uses of fatty acid-derived products are mainly in the detergent, personal care, soap, cosmetics, and plastics sector. In 2000 the world production capacity of fatty acids was more than 5 million metric tons, with renewable fats and oils being the most important... 

Typical enulsifiers used in emulsion polymerization of VC are anirmic emulsifiers like sodium alkyl sulfonates, sodium diaUcyl sulfosucdnates, fatty acid soaps and sodium ethoxy sulfates. Neutral emulsifiers like alltyl phenol ethoxylates and fatty acid ethoxylates are often added during after polymerization in Oder b> increase latex stability. The emulsifiers are not only chosen for control of the particle formation and latex stability during polymerization, but for a number of other reasons like mechanical stability, reactor wall build-up, plastisol formation, heat and colour stability and water resistance of the final product [1]. 

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