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The aqueous solution properties of polyglycidol-based analogues are examined by rhealogy in relation to pluronic block polymers. Shear thinning is observed at concentrations above the critical micellization concentration. Zero shear viscosities are maximum at polyglycidol content of 50% wt, and decreased with increase in temperature.

The effects of electrolyte on the hydration behavior F127 triblock copolymer micelles are investigated by using dynamic Stokes' shift and fluorescence anisotropy measurements of coumarin 153 (C153) and coumarin 151 (C151) as fluorescence probes. The results have shown that [Na.sup.+] ions reside deep in the corona region in comparison to [Li.sup.+] ions and larger clusters of F127 micelles are formed above 2M LiCl.

The micelles formed with the binary mixtures of surfactant polyoxyethylene alkyl ethers are characterized by static (SLS) and dynamic light scattering (DLS) experiments. It is found that the micellar length increases with increasing concentration or with raising temperature irrespective of the composition of the surfactant mixtures.

Different methods like time-resolved fluorescence quenching (TRFQ), electron paramagnetic resonance (EPR), conductivity, Krafft temperature, and density measurements are used to characterize the micelles that are formed in water from ammonium dodecyl sulfate (AmDS). The ionization degree of the AmDS micelles is determined from electrical conductivity data using Evans' method.

Conductivity, density and adiabatic compressibility of dodecyldimethylbenzylammonium chloride in aqueous solution, under different range of temperatures are studied using the results of conductometric and densitometric measurements. The results displayed a shallow minimum of the critical micelle concentration (cmc) values at twenty-five degree centigrade, whereas the ionization degree of micelles increased and the standard free energy of micellization decreased with the increase in temperature.

A number of studies were conducted to demonstrate the complicated interplay between interchain association and disaggregation generated by electrostatic repulsive forces in solutions of thermoresponsive amphiphilic copolymers. The observation shows that the temperature-induced aggregation in aqueous solutions of an amphiphilic copolymer can be significantly controlled by electrostatic interactions.

The implementation of the computer simulation-free-energy/molecular thermodynamics (CS-FE/MT) model for evaluating the free energy of micellization is described. The studies have shown that the CS-FE/MT model can be used for making accurate predictions of the free-energy changes associated with forming multicomponent surfactant and solubilizate micelles in aqueous solution where the chemical structures of the surfactants, cosurfactants and solubilizates are different

The phenomenological description of the behavior of surfactant molecules near the critical micelle concentration (CMC) for a pure surfactant solution is presented. The studies provide insight into the local maximum of the chemical potential, local minimum of the surface tension and the estimate of the micelle size.

Different methods are used for examining the interfacial and bulk behaviors of binary and ternary combinations of tetradecyltrimethylammonium bromide ([C.sub.14]TAB), tetradecyltriphenylphosphonium bromide ([C.sub.14]TPB), and tetradecylpyridinium bromide ([C.sub.14]PB). The self-aggregation processes are exothermic and entropy controlled and the ternary micelles are all spherical when compared to the binaries.

The structure and dynamics of the water layer present at the surface of the cationic micelle decyltrimethylammonium bromide by using atomistic molecular dynamics simulations is studied. The results demonstrate that the slow dynamics of hydration layer water is generic to macromolecular surfaces of either polarity.

Rotational diffusion of two structurally similar hydrophobic probes, 2,5-dimethyl-1,4-dioxo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DMDPP) and 1,4-dioxo-3,6-diphenylpyrrolo[3,4-c] pyrrole (DPP) in nonionic Brij-35 micelles as a function of temperature to explore the micellar internal environment is studied. Results show that the anisotrophy decays of both the probes are described by biexponential functions with two time constants.

The light scattering studies on the hydrodynamic radius of TX-100 micelles increases by a factor of 2.2 upon the addition of 2.0 M NaCl due to increase in both the aggregation number and mechanically entrapped water. The micelle gets dehydrated in the presence of electrolyte due to decrease in the thermodynamically bound water, and consequently the 'dry' micelle radius increases.

A thermodynamic theory is developed describing the transfer process of nonpolar substances from water to their pure state and the micellization process. If an error free result is considered (r= -0.2), it is possible to conclude that the absolute value of variation of the standard heat capacity is one order of magnitude bigger than the variation of the standard entropy.