Oleyl groups

Yasuhira, T., Nagase, A., Kuwahara, Y., Sugawara, R. Aggregation of Bursaphelenchus lignicolus (Nematoda Aphelenchoididae) to several compounds containing oleyl group. Appl Entomol Zool 1982 17 46-51. 

The effect of various snake venoms on surface films of lecithin is to remove one of the long-chain fatty-acid groups from the molecule, causing a considerable fall in surface potential 3 this reaction is much slowed by compression of the film as the result of compression is to remove the double bonds in the oleyl group (the one split off) of the lecithin from the surface, it is possible that the lecithinase, the enzyme which splits off the oleyl group, has a molecular structure which fits both the end group and the double bond in the lecithin. 

In a subsequent paper [182], the authors added to the polymeric core solution magnetite NPs that were surface-coated with oleyl groups. By applying thermal annealing, they were able to achieve a hierarchical spatial distribution of NPs that spontaneously migrated in the fiber nanodomains occupied by isoprene blocks (Fig. 23e, f). 

Abstract Phase behavior of penta-, deca- and eicosa-oxyethylene oleyl ether in water were investigated. Differently from ordinary oleyl surfactants, the lipophilic chains of the present surfactants consist of pure oleyl group. The basic feature of the phase behavior extremely resembles that of pure polyoxyethylene hexadecyl ether systems although the solid present regions in the oleyl surfactant systems are very narrow due to the low melting point of oleyl group. 

The lipophilic group of polyoxyethylene oleyl ethers (POEs) used in the present study is almost pure oleyl group because POEs were synthesized from high-purity oleyl alcohol (99.7%). On the other hand, their oxyethyl-ene chains have distribution. If a system contains a large amount of oil, one has to consider the effect of the hydrophilic-chain distribution on the phase behavior, because the solubility of each surfactant of the mixture in oil is largely different [5]. However, critical micelle concentrations of POEs are considered to be very low [6], the effect of the distribution of the hydrophilic chains on the phase behavior may be small except in a very dilute region. 

The feature of the series of the present phase diagrams in the POE/water systems is similar to those in the CieEO /water systems [1], because the phase diagrams of POE(5) and POE(IO) systems are extremely similar to those of C16EO4 and CieEOg systems, respectively. Since the carbon number of the oleyl group is 18, the lipophilic nature of the oleyl group is not very much different from... 

Figure 26.2 shows the structures of two typical triacylglycerols, 2-oleyl-l,3-distearylglycerol (Figure 26.2a) and tristearin (Figure 26.2b). Both occur naturally—in cocoa butter, for example. All three acyl groups in tristearin are stearyl (octadecanoyl) groups. In 2-oleyl-l,3-distearylglycerol, two of the acyl groups are stearyl, but the one...

A mixture of monolauryl phosphate sodium salt and triethylamine in H20 was treated with glycidol at 80°C for 8 h to give 98% lauryl 2,3-dihydro-xypropyl phosphate sodium salt [304]. Dyeing aids for polyester fibers exist of triethanolamine salts of ethoxylated phenol-styrene adduct phosphate esters [294], Fatty ethanolamide phosphate surfactant are obtained from the reaction of fatty alcohols and fatty ethanolamides with phosphorus pentoxide and neutralization of the product [295]. A double bond in the alkyl group of phosphoric acid esters alter the properties of the molecule. Diethylethanolamine salt of oleyl phosphate is effectively used as a dispersant for antimony oxide in a mixture of xylene-type solvent and water. The composition is useful as an additive for preventing functional deterioration of fluid catalytic cracking catalysts for heavy petroleum fractions. When it was allowed to stand at room temperature for 1 month it shows almost no precipitation [241]. 

Figure 4. Phase equilibria for oleyl homologs varying in polar group in bile salt solution...

Under certain conditions hydrogenation may be confined to the —COOH group, e.g., oleic acid —> oleyl alcohol. 

CH2li2 6rl5i ,w3.M+, or alkyl caboxylates H(Cih n W2-M+ withn typically 7-15 and M+ an alkali metal cation, generally sodium, or they may be anionic, such as H(CH2- 12 3+C1- or H(CH2 12 3 3+C1-. The alkyl chains need not be normal i.e., they may be branched, and may be fluorine-substituted. Some natural surfactants are also of importance e.g., lecithins such as 1,2-diacyl glycero-3-phosphate, with the acyl groups being H(CH2 an< n typica-Hy 12 18, the latter possibly oleyl, i.e., unsaturated. 

From the results of Figure 14.3, interestingly, the protein extraction behaviour by dilinoleyl phosphoric acid (DLIPA) is distinct from the result obtained by DOLPA, in spite of the similar hydrophobic chain. The oleyl and linoleyl groups are unsaturated C18 chains. The former has one unsaturated cis-double bond at the position between C9 and CIO, while the latter has two at the position between C9 and CIO and between C12 and Cl 3. The two double bonds in the hydrophobic part of the surfactant DLIPA provide some inflexibility in the chain, which can lead to steric hindrance and to solvation by the organic phase (Figure 14.5). 

The octanol log F values begin at —0.54 for formic, rise to —0.17 for acetic, and 0.33 for propionic. That is, it takes between two and three lipophilic methylene groups to balance the hydrophilic carboxyl group and allow octanol to share the solute equally with water. In oleyl alcohol/ water it takes one additional methylene before a carboxylic acid is lipophilic enough to be equally shared—i.e., log F(0ieyiaic.) = 0 between propionic and butyric acids. In nitrobenzene/water it takes two additional methylenes, in benzene/water it takes three, and in carbon tetrachloride it takes about 4.5 additional methylenes before log F = 0. 

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