Compatibility and dynamics of mixed micelles of polymer associates

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This research project aims to investigate the formation and ordering of mixed micelles with focusing our attention to "mixing and multi-component effects" in the diverse behavior of micelles formed by amphiphilic polymers. We mainly dealt with aqueous sol utions of various hydrophobically-modified poly(ethyleneglycol)s, and used the means of light scattering, x-ray scattering, and viscoelasticity. Contents of the results are classified into the following three issues ; (A)mixed micelles in dilute solution, (B)lyotropic liquid crystals consisting of mixed micelles, and (C)gelation and mixed micellization in amphiphilic substances having multiple associative moieties. Main results obtained are as follows. As for (A), (1)when those which form spherical micelles by themselves are added to the string-type micelles, the micelles change their shapes to be spherical transitionally at a certain composition with increasing composition of the added surfactant. (2)This shape change is associated w … More ith the localization of the guest molecules at the ends of a micelle, which was confirmed by computational simulations based on the self-consistent field(SCF) calculation. As for (B), (3)we can clearly observe the isotroic to liquid-crystal phase transition as a sol-gel transition by mechanical measurements. (4)The hexagonal liquid crystalline phase is relatively stable for the incorporation of guest surfactants which tend to form spherical micelles in dilute solution. (5)To the contrary, the cubic phase becomes easily unstable by the incorporation of guest surfactants. (6)Packing density and association number in the liquid crystalline phase have been evaluated as a function of composition, and discussed with using the results of SCF calculations. (7)In both cases of (A) and (B), we have found good compatibitities between cores of different chemical structures. As for (C), (8)we have observed co-associations between diblock-type and triblock-type surfactants making bridge sand loops over the two components. Less