Micelle formation from free ions

Here clustering of ions of like charge occurs to give a cluster of colloidal size. Unambiguous detection of micelle formation is fairly easy experimentally because  

Electrolytes showing clustering properties are typified by paraffin chain salts where there is a long paraffin-like chain with a cationic group at the end, as in a quaternary ammonium group  

Added salts can encourage the aggregation of ions to micelles, salting out . This is of considerable importance in biological electrolytes, such as bile salts and phospholipids. 

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In contrast to Equations 7 and 8, based on the binding of counter ion to micelle, an equation including a form for the electrostatic part of free energy of micelle formation, Fgi, evaluated from double... 

In the second item above, the presence of bound and free water molecules was noted. Both bound ions and ionic surfactant groups are hydrated to about the same extent in the micelle as would be observed for the independent ions. The dehydration of these ionic species is an endothermic process, and this would contribute significantly to the AH of micellization if ion dehydration occurred. In the next section we discuss the thermodynamics of micellization, but it can be noted for now that there is no evidence of a dehydration contribution to the AH of micelle formation. The extent of micellar hydration can be estimated from viscosity... 

In the second approach, metal-ion/complex was first attached to one of the polymer blocks. A thin film of the resulting polymer metal complex was then obtained by spin coating/solution casting. Alternatively, the polymer metal complex may also be dissolved in a suitable solvent system that selectively dissolves one of the blocks. Micelles or nanosized aggregates formed in this case. The micellization of amphiphilic block copolymers and their use in the formation of metal nanoparticles has been discussed previously.44 A monolayer of micelles was introduced on a substrate surface by dipping or electrostatic attraction. The substrate was then subjected to further chemical or physical treatments as mentioned earlier. The third approach involves the formation of micelles from the metal-free block copolymer in a suitable solvent system. The micelle solution was then added with metal ion, which was selectively coordinated to one of the blocks. These micelle-metal complexes can also be processed by a procedures similar to the second approach. 

In Figure 4 the equilibrium concentration of dodecyl sulfate ions is plotted against the total surfactant concentration for the PEO-NaDS system in the presence of 0.1 M NaN03. While the PEO-NaDS complex formation starts around 1 mmol.kg, the micelles appear in a detectable amount only if the free surfactant ion concentration exceeds the value of 1.3 mmol.kg" (see the 0 PEO curve). The upper limit of the free DS concentration is the value of Cjyj = 1.44 mmoLkg". In the presence of the polymer, the equilibrium DS concentration shows two inflexion points, the position of which is shifted to higher surfactant concentration with increasing polymer content. From the analysis of Equation 5 at constant counter-ion activity, it follows that... 

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