A molecular-level equilibrium partition coefficient model has been formulated and tested for the uptake of aqueous monovalent/divalent cation-salt mixtures into a Nafion 1 17 perfluorosulfonic acid cation-exchange membrane. The model utilizes a simple cylindrical-pore microstructure for Nafion and considers ion hydration free energy changes which occur during solute partitioning, the orientation of water dipoles within a membrane pore due to the strong electric field generated by the membrane's fixed-charge sites, and the formation of contact ion pairs (coordinate covalent bonds) between divalent cations and membrane ion-exchange sites.Membrane structure parameters in the model (pore-radius and pore-wall fixed-charge concentration) were determined from membrane porosity experiments and X-ray diffraction data in the literature. When the fraction of sulfonate sites which bind to divalent cations was used as an adjustable parameter, the model was able to predict accurately the divalent/monovalent cation selectivity (membrane-phase concentrations) of Pb2+ and Cd2+ with a coabsorbed alkali metal cation (either Li+, Na+, K+, or Cs+) for external salt concentrations of 0.05 and 0.25 M. Independent verification and quantification of the extent of divalent cation binding were made by NMR analyses of salt-equilibrated membranes. The NMR results and model predictions for the fraction of total membrane-phase lead that was bound to sulfonate sites were found to be in excellent agreement with an average error less than 6% for a series of 16 uptake experiments with Pb2+ and either Li+ or K+.

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The stereochemistry of addition of a variety of "ate" complexes with such ketones as 4-tertbutylcyclohexanone, 3,3,5-trimethylcyclohexanone, norcamphor, and camphor has been studied. The reaction of LiAl(CH3)4 and LiAl(¿-C^HgLCHs with 4-tertbutylcyclohexanone in benzene, diethyl ether, tetrahydrofuran, and dimethoxyethane results in predominant axial attack to form equatorial alcohol (via methylation), regardless of reactant ratio or reaction time. However, the reaction of other "ate" complexes such as LiB(CH3)4 and Li"M(CH3)2+" compounds (where M = Mg and Zn and n = 1, 2, or 3) with 4-tertbutylcyclohexanone yields predominantly equatorial attack in diethyl ether. Reaction of all ate complexes studied with 3,3,5-trimethylcyclohexanone yields 100% axial alcohol. Reaction of norcamphor and camphor with all ate complexes studied yields 95% endo alcohol and 99% exo alcohol, respectively, regardless of reactant ratio.

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The interaction of anhydrous ferric chloride with nylon 6 has been inferred from Fourier transform infrared spectroscopy (FTIR), wide‐angle x‐ray diffraction (WAXD), thermal (DSC and TGA), and rheological (Rheometrics) measurements. At very low additive concentration of ∼0.25 wt %, an about 50‐fold melt viscosity increase of nylon 6 was observed. However, progressive decrease in melt viscosity was also observed with increasing additive concentrations indicative of degradation as confirmed by the enhancement of weight loss with TGA at a lower temperature. Decrease in crystallinity content of the filled nylon samples is inferred from the reduction of the melting endotherms with DSC, pronounced reduction in diffraction intensity with WAXD, an increase in amorphous CH2 bending band (1400 cm−1) with FTIR. The above results can be attributed to the strong complex formation between the FeCl3 and the NH groups as suggested by the subtraction spectra of FTIR where decreased intensities of the 690, 1200, and 1265 cm−1 bands were observed.