Hydrophobic chains

A Acylsarcosinates. Sodium A/-lautoylsarcosinate [7631-98-3] is a good soap-like surfactant. Table 4 gives trade names and properties. The amido group in the hydrophobe chain lessens the interaction with hardness ions. A/-Acylosarcosinates have been used in dentifrices (qv) where they ate claimed to inactivate enzymes that convert glucose to lactic acid in the mouth (57). They ate prepared from a fatty acid chloride and satcosine ... 

The pify of the leaving group and the hydrophobe chain length can dramatically affect the efficiency of the perhydrolysis reaction. Additionally, the stmcture of the acid portion of the precursor can affect the yield and sensitivity of the reaction to pH. The mono-4-hydroxybenzenesulfonic acid ester of a-decylsuccinic acid (13) undergoes extremely efficient perhydrolysis at much lower pHs than other peracid precursors, eg, decanoyloxybenzene sulfonate (14). This may be because of the neighboring group participation of the adjacent carboxylate as shown in Table 2 (115). 

According to the other kinetic model proposed for the soapless emulsion process, the growing macroradicals may also form micelle structures at earlier polymerization times since they have both a hydrophilic end coming from the initiator and a hydrophobic chain [74]. 

Fig. 32. 2H spectra of a polymer model membrane, cf. Fig. 27b), selectively deuterated at the a-methylene group of the hydrophobic chain. The spectra are compared for the monomer as well as the polymer lamellar phases at the same temperatures, respectively... 

Salts of monovalent metals of alcohol and alcohol ether sulfates are soluble in water, with the solubility dependend on the cation and the chain length. Ammonium salts are more soluble than sodium salts and these are more soluble than potassium salts. On the other hand, sulfates with short hydrophobic chains are more soluble than those with longer chains but the short-chain molecules have a solubilizing effect on the more insoluble longer chain molecules [68], The solubility of sodium salts of different alcohol sulfates is shown in Fig. 2 and the solubility of sodium and potassium salts of dodecyl sulfate is compared. 

Computing the length of the hydrophobic chain transforms Eq. (11) into Eq. 12, which at 35°C is... 

FIG. 9 CMC vs. the average number of carbon atoms (n) in the hydrophobic chain for mixtures of two sodium alkyl sulfates [123]. 

Aggregation numbers increase as the length of the hydrophobic chain increases. The presence of electrolytes also causes an increase in the aggregation... 

The composition of AOS and IOS is determined by the choice of the olefin feedstock, by the way the feedstock is sulfonated and by manufacturing conditions. As will be shown later, the structural parameters such as hydrophobe chain length and branching, the ratio of alkene- to hydroxyalkanesulfonate, and (for AOS) the mono disulfonate ratio determine the physicochemical properties of AOS and IOS these in turn determine the performance of AOS and IOS in their end formulations. 

Effect of hydrophobe carbon number on AOS calcium tolerance. The hydrophobe chain branching and the di monosulfonate ratio were held constant in these experiments (5-7% branching and 5-7% disulfonate). Increasing AOS carbon number from 14-16 to 16-18 and finally to 20-24 greatly decreases the calcium ion tolerance of AOS see Fig. 3. Addition of less than 200 ppm calcium ion reduced the transmittance of an AOS 2024 surfactant to less than 10% of its initial value. Addition of more than 300 ppm calcium ion was required to reduce AOS 1618 solution transmittance by a similar amount. AOS 1416 was the most calcium-tolerant surfactant. Approximately 400 ppm calcium ion was required to reduce the transmittance of AOS 1416 solution to 10% of its initial value. 

Effect of hydrophobe chain branching. The effects of hydrophobe structure on olefinsulfonate calcium ion tolerance were studied for AOS, IOS, and vinylidenesulfonate (VOS), and the results are shown in Table 7. 

Compared with sodium w-alkyl sulfates the ester sulfonates with the same number of carbon atoms in the hydrophobic chain have lower CMC values because the methyl group also contributes to the micellization. 

The retention of potent enzyme inhibition and in vitro antiviral activity in the presence of functionalisation with relatively long hydrophobic chains at C-7 of zanamivir has been exploited in the development of di- and poly-valent structmes carrying zanamivir (reviewed in Sun 2007). Multivalent presentation of drug may... 

The peripheral substitution with hydrophobic chains on one hemisphere and hydrophilic groups on the other provides the perfect hydrophobic/hydrophilic balance allowing the formation of stable Langmuir films. In addition, a perfect reversibility has been observed in successive compression/decompression cycles (Fig. 18). 

ANANDAMIDE TRANSPORT INHIBITORS The Hydrophobic Chain The Carboxamide/Carboxylate Group The Polar Head Group... 

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