To utilize the fascinating properties of clays, including their large surface areas, many dissociable cations in the interlayers and low-dimensional structure, we focused on controlling the orientation of clay layers in ion-conductive polymer electrolytes. The application of a strong magnetic field is one of the effective methods used to control the orientation of clay layers and to improve the ionic conductivity of the clay composites. In this study, two different composite films were obtained using different orientations of the magnetic field: perpendicular (M ?) and parallel (M //) to the film surface. From two-dimensional wide-angle X-ray diffraction measurements, the montmorillonite (MMT) layers preferentially oriented along the direction of the magnetic fields in the composites. There were substantial correlations between the conductivity and the ratio of MMT layers oriented along the direction of the conductivity measurement. The lowest conductivity was observed in the M // composite, whereas the M ? composite showed very good conductivity. The value was higher than that of the original electrolytes (PMEO 10 LiClO 4) at 30 1C. These results clearly suggest that the orientation direction of the MMT layers toward the direction parallel to the conductivity measurement causes an improvement in the conductivity of the composites. In particular, the conductivity value of the M ? composite with 5 wt% Li-MMT was 1.2 Â 10 À5 S cm À1 at 30 1C, which was more than six times higher than the original electrolyte.
The composite material P(EO/EM)-Sa consisting of synthetic saponite (Sa) dispersed in poly[ethylene oxide-co-2-(2-methoxyethoxy)ethyl glycidyl ether] (P(EO/EM)) is studied by "in situ" measurements using broadband electrical spectroscopy (BES) under pressurized CO2 to characterize the dynamic behavior of conductivity and the dielectric relaxations of the ion host polymer matrix. It is revealed that there are three dielectric relaxation processes associated with: (I) the dipolar motions in the short oxyethylene side chains of P(EO/EM) (β); and (II) the segmental motion of the main chains comprising the polyether components (αfast, αslow). αslow is attributed to the slow α-relaxation of P(EO/EM) macromolecules, which is hindered by the strong coordination interactions with the ions. Two conduction processes are observed, σDC and σID, which are attributed, respectively, to the bulk conductivity and the interdomain conductivity. The temperature dependence of conductivity and relaxation processes reveals that αfast and αslow are strongly correlated with σDC and σID. The "in situ" BES measurements under pressurized CO2 indicate a fast decrease in σDC at the initial CO2 treatment time resulting from the decrease in the concentration of polyether-M(n+) complexes, which is driven by the CO2 permeation. The relaxation frequency (fR) of αslow at the initial CO2 treatment time increases and shows a steep rise with time with the same behavior of the αfast mode. It is demonstrated that the interactions between polyether chains of P(EO/EM) and cations in the polymer electrolyte layers embedded in Sa are probably weakened by the low permittivity of CO2 (ε = 1.08). Thus, the formation of ion pairs in the polymer electrolyte domains of P(EO/EM)-Sa occurs, with a corresponding reduction in the concentration of ion carriers.
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