Counterion binding degree

Here (log cmc) is tire log cmc in tire absence of added electrolyte, is related to tire degree of counterion binding and electrostatic screening and c- is tire ionic strengtli (concentration) of inert electrolyte. Effects of added salt on cmc are illustrated in table C2.3.7. 

In Figure 3, the curves for the ionic/ionic systems are all below the curve for the nonionic/nonionic case. As the degree of counterion binding increases, i.e. as y9j and increase, the value of c /c2 decreases for a given value of a. The bottom curve in Figure 3 corresponds to the ionic/ionic system with Pi = 0.6, P2 = 0.0, and P = 1.0. This case is probably physically unrealistic, inasmuch as these parameters correspond to a system in which both surfactants 1 and 2 are ionic and contribute counterions to the system but surfactant 2 in the micelles acts as a nonionic surfactant and therefore has a zero degree of counterion binding. 

Rationalization of the packing of the AA headgroups at the water-air interface is, unfortunately, less than straightforward [97]. The absence of information concerning the extent of headgroup ionization (at a bulk pH of 5.5), counterion binding and the degree of hydration hinders the interpretation of... 

The effect of methanol on micellar solutions is slight at the low concentration used (5% v/v = 1.3 mol/L = 0.022 mole fraction). The effect of NaCl however, is more significant the CMC is greatly decreased, the degree of counterion binding and the aggregation number are increased. 

Solution behavior of ionomers can be divided into two types, primarily depending on the polarity of the solvent [46,47], One is polyelectrolyte behavior due to the dissociation of counterions in polar solvents (e.g., DMF), and another is association behavior due to the formation of ion pairs and even higher order aggregates in less polar solvents (e.g., THF). Table 2 shows the solvents frequently used for the study of ionomer solutions, as well as their dielectric constants. As the dielectric constant decreases, the degree of counterion binding and also ion pair formation changes (increases) gradually, and so does the solution behavior. In this chapter, only the polyelectrolyte behavior of ionomers in a polar solvent is described. Some brief... 

Much less is known about micellar charge and counterion binding in the case of bile salts. Based on the result of ionic self-diffusion measurements [20,163,173], conductance studies [17,18,187], Na, and Ca activity coefficients [16,19,144,188,189] and NMR studies with Na, Rb and Cs [190], a number of generalities can be made. Below the operational CMC, all bile salts behave as fully dissociated 1 1 electrolytes, yet interionic effects between cations and bile salt anions decrease the equivalent conductance of very dilute solutions [17,18,187]. With the onset of micelle formation, counterions become bound to a small degree values at this concentration are about < 0.07-0.13 and are not greatly influenced by the species of monovalent alkali cations [163,190]. At concentrations above the CMC, values remain relatively constant to 100 mM in the case of C and this... 

For non-ionic/ionic mixed micelles the degree of counterion binding must be proportional to the mole fraction of ionic component, in contrast to experimental observations. 

Theories, considering changes of the micellar electrical potential and degree of counterion binding form a third group [29, 30, 47, 48]. 

If the adsorption values are the same in both relations (5.143), an expression for the degree of counterion binding from experimental surface tensions can be easily obtained... 

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