We demonstrate that miscibility affects the ionic conductivity of ternary polymer blends of lithium perchlorate (LiClO4), poly(ethylene oxide) (PEO), and poly( -caprolactone) (PCL). Although individually these three binary blends are fully miscible, a closed immiscibility loop exists in the ternary blend phase diagram as a result of the complicated interactions among LiClO4, PEO, and PCL. The addition of PCL suppresses the crystallization of PEO and results in higher ionic conductivity. FTIR spectroscopy studies indicate that an excess PCL content causes immiscibility, which results in PCL being excluded from the ternary blends. Consequently, the maximum ionic conductivity (6.3 × 10 -7 S cm -1 ) at ambient temperature of ternary blends having a fixed LiClO4 content (25 wt %) is at a composition of 25/60/15

This study demonstrates that adding clay that was organically modified by dimethyldioctadecylammonium chloride (DDAC) and d2000 surfactants increases the ionic conductivity of polymeric electrolyte. A.C. impedance, differential scanning calorimetric (DSC), and Fourier transform infrared (FTIR) studies revealed that the silicate layers strongly interact with the dopant salt lithium perchlorate (LiClO 4 ) within a poly(ethylene oxide) (PEO)/clay/LiClO 4 system. DSC characterization verified that the addition of a small amount of the organic clay reduces the glass-transition temperature of PEO as a result of the interaction between the negative charge in the clay and the lithium cation. Additionally, the strength of such a specific interaction depends on the extent of PEO intercalation. With respect to the interaction between the silicate layer and the lithium cation, three types of complexes are assumed. In complex I, lithium cation is distributed within the PEO phase. In complex II, lithium cation resides in an PEO/exfoliated-clay environment. In complex III, the lithium cation is located in PEO/ agglomerated-clay domains. More clay favors complex III over complexes II and I, reducing the interaction between the silicate layers and the lithium cations because of strong self-aggregation among the silicate layers. Notably, the (PEO) 8 LiClO 4 /DDACmodified clay (DDAC-mClay) composition can form a nanocomposite electrolyte with high ionic conductivity (8 ϫ 10 Ϫ5 S/cm) at room temperature.

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