Chlorate micelles

The large deviation in the exponent for the viscosity from the prediction of the living polymer model has also been reported for other systems [2, 3]. For example, Khatory et al. have performed rheological measurements on cetypyridinium chlorate micelles in NaClOs brine [31]. The obtained exponents are 2 and 1 for 0.1 M and 1M NaClOs, respectively. Hoffmann has measured the viscosity on tetrade-cyldimethylaminoxide (C14DMAO)/ decanol/water system for different ratios of CuDMAOidecanol [2, 3]. He has shown that the exponent decreases from about 5.4 to 1.3 as the ratio of decanol increases from 0 to C14DMAO decanol = 5 1. 

A better method for studying the alkali metal cation-soap anion interaction on the surface, according to Weil (58), is to assume a similarity between surface behavior and solution behavior and to use the activity coefficient of the solute in the solution as the parameter to account for surface behavior. By plotting activity coefficients as a function of the molality for the salts of the alkali metals (7, 26), the resulting order of the curves of the weak acids (formates, acetates, hydroxides) is the reverse of that found for the strong acids (chlorides, bromides, nitrates, chlorates, sulfates). The activity curves of the acetate salts can be used as the counterparts for the long-chain fatty acid salts, while those for the chlorides can be the analogs of the alkyl sulfates. The scheme is speculative in that the fatty acid and alkyl sulfate salts micellize, and acetate and chloride do not. 

The shape and size of self-assembled micellar systems depend on the conditions for a given system. Changes can be induced, e.g., by addition of cosurfactant or salt or by high surfactant concentrations. An aqueous solution of cetyltrimethylammonium chloride (CTAC) exhibits a transition from spherical micelles to elongated cylinders upon addition of chlorate anions, which is shown, for instance, by a strong increase in viscosity [25]. This system was experimentally studied by TRLQ, with results in good agreement with theory, as shown in Fig. 4. 

The probe and quencher were in this case hydrophobic enough to be confined within the aggregates. By choosing a low probe concentration and low intensity of the excitation flash, it was ensured that no aggregate contained more than one excited lumophore. A characteristic feature of the decay curve family in Fig. 4 is that all curves start in the same nonexponential way but separate and become linear and parallel to the unquenched exponential curve after a certain time, which is longer the larger the micelles. There is no difference between the curves for the two highest concentrations of chlorate, in spite... 

---

See also in sourсe #XX -- [ ]

---