The X-ray patterns of lithium (LiDC) and potassium (KDC) deoxycholate fibers, drawn from aqueous micellar solutions, have been interpreted by means of a packing of 8/1 helices formed by trimers. Previously, these helices satisfactorily represented the structure of the sodium (NaDC) and rubidium (RbDC) deoxycholate micellar aggregates. Dielectric measurements show that the trend of the average electric dipole moment µ of a NaDC monomer as a function of temperature and concentration supports a two-structure equilibrium. The high µ values (32-58 D) can be explained by the remarkable hydration of the NaDC micellar aggregates. The µ moderate decrease when the size of the aggregates increases can agree with the presence of small helices but disagrees with the existence of aggregates that are disordered or have a center (or a pseudocenter) of symmetry. Formerly, it was observed that sodium taurodeoxycholate (NaTDC) micellar aggregates, represented by 7/1 helices, formed by trimers, behave similarly. The contribution to the electrical conductivity of NaDC and NaTDC in aqueous solutions containing NaCl tends to zero by increasing the NaCl concentration, denoting strong interactions between Na + ions and anion aggregates. According to the similar 7/1 and 8/1 helices, which have the Na + ions in their inner part, the micellar size and the fraction of Na + ions trapped inside the helices increase together. The aggregate apparent hydrodynamic radius (R h ) increases by increasing the ionic strength in the order LiDC > NaDC > KDC > RbDC. Fibers drawn from solutions containing two cations at the same concentration show that the affinity for the anionic structure seems to follow the order Li + > Na + > K + > Rb + at high ionic strength. The R h values vs the mole fractions of Li + and Rb + or Na + and K + at lower ionic strength are fitted by straight lines. Probably, the free energy gains, associated with the cation and anion transfer from the bulk solution to the micellar aggregates, are almost equal for the four salts at lower ionic strength.

A number of microporous fairly hydrophilic poly(N,N-dimethylacrylamide-methylenebisacrylamide) (poly(DMAA-MBAA)) resins (cross-linking degree from 2 to 8%) have been examined with techniques that provide information on the structure on the nanometer scale and molecular accessibility of these materials in the swollen state. Electron spin resonance (ESR), pulsed-gradient-spin-echo nuclear magnetic resonance (PGSE−NMR) spectroscopies, and inverse steric exclusion chromatography (ISEC) gave consistent results in water, tetrahydrofuran (THF), and dichloromethane (DCM). The results are interpreted on the basis of physical models which fit reasonably the experimental data. The resulting equations between the translational diffusion coefficient of the solvent, the rotational correlation time of the spin-probe 2,2,6,6-tetramethyl-4-oxo-1-oxyl-pyperidine (TEMPONE) dispersed inside the swollen resins, and the polymer chain concentration appear to be promising tools in the design of macromolecular materials for chemical and catalytic applications.