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Saponify

C. A trilerpenoid or irimethylsierol, first found in the non-saponifiable material of wool wax. Lanosterol (4,4,14ot-trimethyl-5a-choiesta-8,24-dien-3 -ol) is the precursor in animals and fungi of other sterols such as... [Pg.234]

Esters of sulphuric acid. These compounds are generally water insoluble liquids and are saponified by boiling with water or dilute alkali to the corresponding alcohols and sulphuric acid ... [Pg.1078]

J. Rebek, Jr., (1987) first developed a new synthesis of Kemp s acid and then extensively explored its application in model studies. The synthesis involves the straightforward hydrogenation (A. Steitz, 1968), esterification and methylation of inexpensive 1,3,5-benzenetricar-boxylic acid (trimesic acid 30/100 g). The methylation of the trimethyl ester with dimethyl sulfate, mediated by lithium diisopropylamide (V. J. Shiner, 1981), produced mainly the desired aff-cis-1,3,5-trimethyl isomer, which was saponified to give Kemp s acid. [Pg.347]

Animal fats and vegetable oils are triacylglycerols, or triesters, formed from the reaction of glycerol (1,2, 3-propanetriol) with three long-chain fatty acids. One of the methods used to characterize a fat or an oil is a determination of its saponification number. When treated with boiling aqueous KOH, an ester is saponified into the parent alcohol and fatty acids (as carboxylate ions). The saponification number is the number of milligrams of KOH required to saponify 1.000 g of the fat or oil. In a typical analysis, a 2.085-g sample of butter is added to 25.00 ml of 0.5131 M KOH. After saponification is complete, the excess KOH is back titrated with 10.26 ml of0.5000 M HCl. What is the saponification number for this sample of butter ... [Pg.363]

Acryhc esters may be saponified, converted to other esters (particularly of higher alcohols by acid catalyzed alcohol interchange), or converted to amides by aminolysis. Transesterification is comphcated by the azeotropic behavior of lower acrylates and alcohols but is useful in preparation of higher alkyl acrylates. [Pg.150]

The use of the various tempera and of wax has been identified on objects dating back to ancient Egypt. The Eayum mummy portraits are beautiful examples of encaustic painting, ie, using molten wax as medium. A rather special variation was the technique used by the Romans for wall paintings. In these, the medium, referred to by Pliny as Punic wax, probably consisted of partially saponified wax. In Europe, wax ceased to be used by the ninth century. [Pg.420]

The sulfur amino acid content of soy protein can be enhanced by preparing plasteins from soy protein hydrolysate and sources of methionine or cystine, such as ovalbumin hydrolysate (plastein AB), wool keratin hydrolysate (plastein AC), or L-methionine ethyl ester [3082-77-7] (alkaU saponified plastein) (153). Typical PER values for a 1 2 mixture of plastein AC and soybean, and a 1 3 mixture of alkah-saponified plastein and soybean protein, were 2.86 and 3.38, respectively, as compared with 1.28 for the soy protein hydrolysate and 2.40 for casein. [Pg.471]

Maleic acid and fumaric acid can also be, and are often, incorporated in alkyd resins in the form of the Diels-Alder adduct of rosin. The adducts are tribasic acids which provide pendent carboxyl groups in the resin molecules, which can be saponified to give ionic, and, in turn, water-soluble characteristics to the resin. However, the resultant alkyds often have poorer color retention, toughness, gloss retention, and exterior durabiUty. [Pg.33]

In the initial black Hquor concentration, saponified fatty and resin acid salts separate as tall oil soaps (see Tall oil). These soaps can be skimmed from the aqueous spent Hquor, acidified, and refined to give a cmde tall oil composed of resin acids, chiefly abietic and neoabietic fatty acids, chiefly oleic and Hnoleic and an unsaponifiable fraction made of phytosterols, alcohols, and hydrocarbons. Tall oil is fractionated primarily into fatty acids (see... [Pg.270]

Composition. Rosin is primarily a complex mixture of monocarboxyUc acids of alkylated hydrophenanthrene nuclei. These constituents, known as resin acids, represent about 90% of rosin. The resin acids are subdivided into two types, based on their skeletal stmcture. The abietic-type acids contain an isopropyl group pendent from the carbon numbered 13. The pimaric-type acids have a methyl and vinyl group pendent from the same carbon atom. Figure 1 shows the stmcture of typical resin acids abietic acid, C2QH2QO2 (1) is predominant. The remaining 10% of commercial rosin consists of neutral materials that are either hydrocarbons or saponifiable esters. These materials are derived from resin acids by decarboxylation or esterification. [Pg.138]

Rubars DuBois Chemicals 1.04 60—85 (bars) saponified fatty acids... [Pg.245]

Continuous Saponification Systems. A relatively recent innovation in the production of soap, these systems have led to improved manufacturing efficiency and considerably shorter processing times. There are a number of commercial systems available even though these systems are different in design aspects or specific operations, they all saponify fats and oils to finished soap using the same general process (Fig. 3). [Pg.153]

Uses ndReactions. The Prins reaction of 3-carene with formaldehyde in acetic acid gives mainly 2-carene-4-methanol acetate, which when saponified produces the 2-carene-4-methanol, both of which are commercial products of modest usage (60). 3-Carene (28) also reacts with acetic anhydride with a catalyst (ZnCl2) to give 4-acetyl-2-carene (29) (61), which is also a commercial product. Although 3-carene does not polymerize to produce terpene resins, copolymerization with phenol has been successfully commercialized by DRT in France (62). [Pg.414]

Rosin is commonly modified with maleic or fumaric acid to improve efficiency. Since the 1970s, dispersions of unsaponifted rosin have become more popular as a result of their improved sizing efficiency, lower alum requirements, and reduced pH sensitivity vs saponified rosins. Cationic dispersed rosin size, which can be effective at near-neutral and neutral papermaking conditions, is also available (63—65). Commercially available rosin sizes include Pexol, Neuphor, and Hi-pHase (Hercules Inc.), Plasmine and NeuRos (Plasmine), Stafor (Westvaco), Novaplus, and Novasize (Georgia Pacific), and NeuRos and Roscol (Akzo Nobel). [Pg.310]

The alkahes do not sequester heavy-metal ions and have Httie soil-suspending effect. They are effective in maintaining a high pH and saponify the acidic constituents of soil and thus promote cleaning. In the cleaning of ceramics, glass, and metal surfaces, however, the alkahes act as primary detergents even in the absence of surfactants in these systems. [Pg.528]

Cellulose Diacetate. When preparing cellulose diacetate for dyeing, strong alkahes must be avoided in the scouring of acetate because the surface of the cellulose acetate would be saponified by such treatment. Many fabrics tend to crease and therefore requke open-width handling. Scouring is frequendy carried out on a jig or beam using 1.0 g/L of surfactant and 0.5—1.0 g/L tetrasodium pyrophosphate for 30 min at 70—80°C. [Pg.365]

The bound chloiine formed does not readily saponify with metal hydroxide solutions and is analyzed as part of the total chlorine of the resin. (3) Incomplete dehydrohalogenation which results in residual saponifiable or hydrolyzable chlorine ... [Pg.366]

The flask is then fitted with a reflux condenser and the contents boiled for two hours. In order to saponify the small amount of ester which is produced, a solution of 20 g. of sodium hydroxide in 30 cc. of water is then added and boiling continued... [Pg.96]

Alkaline cleaners (caustic based) These are caustic soda based and are suitable for ferrous metals only. They are more effective in removing greases of vegetable oils, rather than mineral (petroleum) oils, as they do not saponify the mineral oils. [Pg.400]

C. Saponification. The ester is saponified by refluxing for 5 hours with 75 ml. of a 10% sodium hydroxide solution containing 3 ml. of ethyl alcohol it is then poured into 150 ml. of water and decolorized with Norite. Upon acidification of the alkaline solution with dilute hydrochloric acid, 18-19 g. (40-43%) (Notes 7 and 8) of acid is obtained, melting at 191-193° (corr.). [Pg.30]


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See also in sourсe #XX -- [ Pg.240 ]

See also in sourсe #XX -- [ Pg.199 , Pg.360 ]

See also in sourсe #XX -- [ Pg.138 ]




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Non-saponifiable compounds

Rayon saponified acetate

Saponifiable lipids

Saponified

Saponified

Saponified Cellulose Acetate

Saponified graft copolymers

Saponified starch-g-polyacrylonitrile

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