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Acids esterifying

Other minor raw materials are used for specific needs. Eumaric acid [110-17-8] the geometric isomer of maleic acid, is selected to maximize thermal or corrosion performance and is the sole acid esterified with bisphenol A diol derivatives to obtain optimum polymer performance. CycloaUphatics such as hydrogenated bisphenol A (HBPA) and cyclohexanedimethanol (CHDM) are used in selective formulations for electrical apphcations. TetrahydrophthaUc anhydride [85-43-8] (THPA) can be used to improve resiUence and impart useful air-drying properties to polyester resins intended for coating or lining apphcations. [Pg.313]

Acylglycerols can be hydrolyzed by heating with acid or base or by treatment with lipases. Hydrolysis with alkali is called saponification and yields salts of free fatty acids and glycerol. This is how soap (a metal salt of an acid derived from fat) was made by our ancestors. One method used potassium hydroxide potash) leached from wood ashes to hydrolyze animal fat (mostly triacylglycerols). (The tendency of such soaps to be precipitated by Mg and Ca ions in hard water makes them less useful than modern detergents.) When the fatty acids esterified at the first and third carbons of glycerol are different, the sec-... [Pg.242]

Phosphatidic acid, the parent compound for the glycerol-based phospholipids (Figure 8.4), consists of 5w-glycerol-3-phosphate, with fatty acids esterified at the T and 2-positions. Phosphatidic acid is found in small amounts in most natural systems and is an important intermediate in the biosynthesis of the more common glycerophospholipids (Figure 8.6). In these compounds, a... [Pg.244]

Examples of polyfunctional carboxylic acids esterified by this method are shown in Table I. Yields are uniformly high, with the exception of those cases (maleic and fumaric acids) where some of the product appears to be lost during work-up as a result of water solubility. Even with carboxylic acids containing a second functional group (e.g., amide, nitrile) which can readily react with the oxonium salt, the more nucleophilic carboxylate anion is preferentially alkylated. The examples described in detail above illustrate the esterification of an acid containing a labile acetoxy group, which would not survive other procedures such as the traditional Fischer esterification. [Pg.62]

Paraplex. A trademark for a group of alkyd type polymeric materials known as polyester resins. These resins are primarily long chain polybasic acids esterified with polyhydric alcohols such as glycol sebacate, glycerol, or ethylene glycol. Some are oil-modified while others are unmodified polyesters... [Pg.489]

Phosphoric acid esterified with polyethoxylated p-nonylphenol. [Pg.284]

In general, these authorities agree that pyrethroids containing both a halogenated acid esterified with the a-cyano-3-phenoxybenzyl alcohol — such as fenvalerate, deltamethrin, and cyper-... [Pg.1099]

These are the most common class of complex lipid (Figure 12.11) and contain a phosphoric acid residue (phosphate group) and two fatty acids esterified to glycerol. Attached to the phosphate group is an amino alcohol, sometimes referred to as the nitrogenous base, which may be either serine, choline or ethanolamine or sometimes the monomethyl or dimethyl derivatives of ethanolamine (Table 12.4). Alternatively, a polyhydroxy compound which is either glycerol, myo-inositol or one of their derivatives is attached instead... [Pg.416]

Prodrugs of Active Carboxylic Acids Esterified with a Phenol or Hydroxylamine... [Pg.436]

The stress relaxation properties of SA-modified wood in media of different pH have also been studied (Nakano etal., 1990a,b, 1991 Nakano, 1993a,b). It was found that an increase in pH led to an increase in stress relaxation properties due to side chain ionization, with maximum swelling of the wood occurring between pH 5-8. In addition, cross-linking within the wood was achieved by treatment with bivalent or trivalent metal ions. The rheological properties of maleic acid esterified wood also show that thermoplasticity is imparted to the wood by such modification (Norimoto etal, 1992). [Pg.82]

Seed oil triglycerides consist of three fatty acids esterified to glycerin. Although most plants produce at least some Cie fatty acids, the majority of the triglycerides are comprised of Cig fatty acids. The balance of the fatty acids is quite specific to the plant from which the oil is derived, but the most prominent fatty acids among all plant species consist of a series of 18-carbon fatty acids containing zero, one, two, or three sites of unsaturation. These fatty acids are stearic, oleic, linoleic, and linolenic acids, respectively. These are the main fatty acids found in most seed oils and are illustrated in Fig. 5. [Pg.323]

Triacylglycerol. Triglyceride a compound consisting of three molecules of fatty acids esterified to glycerol. It is a neutral fat synthesized from carbohydrates for storage in animal adipose cells. On enzymatic hydrolysis, it releases free fatty acids in the blood. Tuberculosis. Any of the infectious diseases of man and animals caused by species Mycobacterium and characterized by the formation of tubercles and caseous necrosis in the tissues. [Pg.576]

The principal components of oils and fats on which all the physical and chemical properties depend are the TAG molecules. The TAGs are in turn made up of a variety of fatty acids esterified to the hydroxyl groups on glycerol molecules. TAG profiles of morama bean oil has been carried out by Mitei et ah (2008) who found seven major TAG classes, with the dominating classes being C54 4, C54 3, and C52 3. Occupancy of the sn-1 and sn-3 positions is 45.0% saturated, 38.4% oleoyl, and 16.6% linoleoyl. The sn-2 position is occupied by oleoyl (56.4%) and linoleoyl (43.6%). [Pg.198]

Arac hiidonic acid esterified in membrane phospholipids... [Pg.397]

The polar lipids, with polar heads and nonpolar tails, are major components of membranes. The most abundant are the glycerophospholipids, which contain fatty acids esterified to two of the hydroxyl groups of glycerol, and a second alcohol, the head group, esterified to the third hydroxyl of glycerol via a phosphodiester bond. Other polar lipids are the sterols. [Pg.355]

Two of the arms of a tRNA are critical for its adaptor function. The amino acid arm can carry a specific amino acid esterified by its carboxyl group to the 2 - or... [Pg.1050]

Structure of triacylglycerols (TAG) The three fatty acids esterified] to a glycerol molecule are usually not of the same type. The fefy I acid on carbon 1 is typically saturated, that on carbon 2 is typi-j cally unsaturated, and that on carbon 3 can be either. Recall thal the presence of the unsaturated fatty acid(s) decrease(s) thl I melting temperature of the lipid. An example of a TAG molecule H shown in Figure 16.12. [Pg.186]


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Esterified

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