Decanol, solubilization

The solubilization of decanol and toluene in micellar solutions of surfactant [Q] with X = OH was investigated by small-angle neutron seattering (SANS). The micelles were modeled as spheres (for toluene solubilization) and cylinders (for decanol solubilization) in order to fit the SANS data. A growth of the micelle dimensions was thus evidenced upon addition of toluene and decanol [100]. 

An example for a partially known ternary phase diagram is the sodium octane 1 -sulfonate/ 1-decanol/water system [61]. Figure 34 shows the isotropic areas L, and L2 for the water-rich surfactant phase with solubilized alcohol and for the solvent-rich surfactant phase with solubilized water, respectively. Furthermore, the lamellar neat phase D and the anisotropic hexagonal middle phase E are indicated (for systematics, cf. Ref. 62). For the quaternary sodium octane 1-sulfonate (A)/l-butanol (B)/n-tetradecane (0)/water (W) system, the tricritical point which characterizes the transition of three coexisting phases into one liquid phase is at 40.1°C A, 0.042 (mass parts) B, 0.958 (A + B = 56 wt %) O, 0.54 W, 0.46 [63]. For both the binary phase equilibrium dodecane... 

The situation is further confused by qualitative observations, such as the conflicting views as to the solubilizing effect or otherwise of the CH2OH group in kojates and derived hydroxypyridinonates (238). In relation to Table XVIII, the trend of increasing solubility from water to ethanol followed by a steady decrease to 1-decanol, common to ethylmaltol and its iron complex, resembles that established for Fe(bipy)2(CN)2 and Fe(phen)2(CN)2, though in the case of these... 

So far it has not been possible to measure the chemical potentials of the components in the mesophases. This measurement is possible, however, in solutions which are in equilibrium with the mesophases. If pure water is taken as the standard state, the activity of water in equilibrium with the D and E phases in the system NaC8-decanol-water is more than 0.8 (4). From these activities in micellar solutions, the activity of the fatty acid salt has sometimes been calculated. The salt is incorrectly treated as a completely dissociated electrolyte. The activity of the fatty acid in solutions of short chain carboxylates has also been determined by gas chromatography from these determinations the carboxylate anion activity can be determined (18). Low CMC values for the carboxylate are obtained (15). The same method has shown that the activity of solubilized pentanol in octanoate solutions is still very low when the solution is in equilibrium with phase D (Figure 10) (15). 

Solvent polymeric membranes that incorporate quaternary ammonium salt anion-exchangers, such as tri-n-octylpro-pylammonium chloride decanol, are used to construct CP-selective electrodes in clinical analyzers. Although by far the most common method for measuring CP in clinical laboratories, these electrodes have been described to suffer from membrane instability and lot-to-lot inconsistency in selectivity to other anions. " Anions that tend to be problematic are other halides and organic anions, such as SCN", which can be particularly problematic because of their ability to solubilize in the polymeric organic membrane of these electrodes. 

Polymeric quaternary ammonium surfactants made from w-dodecyl bromide and poly(2-vinylpyridine) are better solubilizers for oil-soluble azo dyes and for n-decanol than monomeric quaternary cationics with similar (monomeric) structures (Tokiwa, 1963 Inoue, 1964). Solubilization of n-decanol in the polycationics increased as the alkyl chain content increased to a maximum at 24% alkyl content and resulted, at high decanol content, in intermolecular aggregation of the poly cationic molecules (Inoue, 1964). 

Fontell studied the solubilization of n-decanol by NaDC (38). His phase diagram is redrawn in Fig. 55 and demonstrates that bile salt in adequate quantities produces a single liquid phase extending from pure water to pure decanol. Thus, bile salt not only solubilizes decanol in an aqueous solution (left side) but also solubilizes water in a decanol solution (right side). 

The interactions of another alcohol, cholesterol, with water and bile salt have been studied at 20 and 37 °C (2, 6, 47). Figure 56 shows that unlike decanol bile salt does not solubilize cholesterol well. Both free and conjugated bile salts are ineffective (6, 47). Perhaps the bulky steroid nucleus. 

The situation is, however, more unpredictable at surfactant concentrations well in excess of the CMC when other effects of electrolyte on micellar properties predominate. The complexity is demonstrated by a detailed study by Ekwall et al [166] of the effect of sodium chloride on the solubilization of decanol by sodium octanoate. At low octanoate concentrations (up to about 0.3 mol 1 the decanol solubility, as expected, begins to increase only when the CMC is exceeded and the increase proceeds up to the highest chloride additions studied (Fig. 5.20). However, at octanoate concentrations > 0.3 mol 1 the first chloride additions caused a more or less pronounced increase of decanol solubility, but this increase is changed to a decrease at further increase of the salt concentration the maximum of the solubility curve occurs at lower sodium chloride when the octanoate content of the system is increased. At octanoate concentrations above about 0.7 mol 1 the addition of salt caused an immediate decrease in the solubilizing capacity of the system. This complex effect of added salt was... 

Figure 5.26 Solubilization and cloud-point curves of 1 % Cjo H210 (CH2 CH2 O)io CH3 solutions in the presence of added n-decanol. After Nagakawa and Tori [152].

Chem. Descrip. POE (20) decanol Ionic Nature Nonionic Uses Solubilizer cleansing agent Properties Liq. HLB 17 cloud pt, 75 C (1% in NaC110%) lmbentln-AG/102/045 [Dr. W. Kolb AG]... 

A concentrated surfactant solution containing a hexagonal close-packed meso-phase would be appropriate for solubilizing which of the following materials in the discontinuous phase butyl myrstate, n-decanol, or lecithin. 

A study of the solubilization of decanol in solutions of sodium octanoate showed that at low surfactant concentrations the solubilization of the additive increased rapidly after the cmc was exceeded, and continued to do so for some time as the concentration of sodium chloride was increased. At higher surfactant concentrations, however, it was found that there was an initial increase in decanol incorporation, which reached a maximum and then began to decrease as the salt level continued to increase. When the octanoate concentration well exceeded the cmc, the addition of salt resulted in an immediate decrease in the ability of the system to incorporate the additive. Such complex interactions have been attributed to alterations in the thermodynamics of mixed micelle formation for the decanol and carboxylate salt. Similar results may be seen in systems where the increased electrolyte content produces a change in the character of the micellar system a sphere-to-rod micellar transformation or the development of a mesophase, for example. 

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