A series of ether group and amino group cosubstitutent phosphazene copolymers was synthesized and characterized by a combination of NMR, elemental analysis, and FTIR spectroscopy. The length of the alkyl group in the amino side chain and the content of the methoxyethoxyethoxy (MEE) substituent on the polymer properties were varied. Dynamic mechanical analysis (DMA) demonstrated that the cosubstitutent polymers prepared have better mechanical properties than the ether homopolyphosphazene, poly[bis(2-methoxyethoxy)ethoxy]phosphazene, MEEP. The copolymers that possessed multiple electron-donor coordination sites, nitrogen and oxygen atoms, were complexed with various amounts of lithium perchlorate (LiClO 4) to form polymer electrolytes. The ionic conductivity of the polymer electrolytes were determined by an impedance analyzer in a temperature range of 30-80 °C. According to those results, the conductivities of the prepared polymer electrolytes increased according to the rise in the MEE side chain contents and reached optima at F ) 0.2-0.25. The best conductivity obtained is 2.2 × 10 -5 S/cm for CPE-3A with F ) 0.25.

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Montmorillonite clay was modified with four kinds of quaternary alkylammonium salts to enable the intercalation of polyacrylonitrile (PAN) into the resulting organophilic clay in PC/EC cosolvents. X-ray diffraction experiments revealed that PAN was able to intercalate in the clay galleries. The exfoliation and intercalation phenomena were also confirmed by transmission electron microscopy. A series of gel PAN/clay nanocomposite electrolyte materials were successfully prepared by incorporating appropriate fractions of PAN, organophilic clay, PC/EC cosolvent, and LiClO 4. The PAN/clay nanocomposite electrolyte shows a maximum ionic conductivity of 1.4 × 10 -2 S/cm and exhibits superior ability in film formation and plasticizer absorption, and dimensional stability in comparison to the electrolyte that contains no organophilic clay. Cyclic voltammetric data indicated that the addition of organophilic clay significantly enhances the electrochemical stability of the composite electrolyte system.

Four quaternary alkyl ammonium salts were used in an organophilic procedure, performed on montmorillonite clay, and resulted in intercalation in dimethylformamide (DMF) or ethylene carbonate (EC)/propylene carbonate (PC) as a cosolvent between poly(vinylidene fluoride) (PVdF) and the organophilic clay. An examination using X‐ray diffraction revealed that PVdF entered galleries of montmorillonite clay, and it exhibited exfoliation and intercalation phenomena when it was analyzed with transmission electron microscopy. Gel PVdF nanocomposite electrolyte materials were successfully prepared by the addition of the appropriate percentages of DMF or PC/EC as a cosolvent, organophilic clay, and lithium perchlorate to PVdF. The maximum ionic conductivity was 1.03 × 10−2 S/cm, and the materials exhibited better film formation, solvent‐maintaining capability, and dimensional stability than electrolyte films without added organophilic clays. The results of cyclic voltammetry testing showed that the addition of the organophilic clays significantly enhanced the electrochemical stability of the polymer electrolyte system. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3873–3882, 2002

Two series of new phosphazene polymer electrolytes, PPAP/LiClO4 and PHAP/LiClO4, were prepared by complexing lithium perchlorate, LiClO4, to poly(bis(pentylamino)phosphazene), PPAP, and poly(bis(hexylamino)phosphazene), PHAP, respectively. The electrolytes were characterized by the combination of FTIR, 31P-NMR, and 13C-NMR spectroscopies. Films of these electrolytes showed good dimensional stability and ionic conductivity. The glass transition temperatures were determined by differential scanning calorimetry. The highest ionic conductivity, σ, was 7 orders higher in magnitude than the σ of its parent polymer and was similar to the σ of PEO at room temperature. The plots of ionic conductivity versus temperature for the polymer electrolytes were found to correspond to the Vogel−Tammann−Fulcher equation throughout the temperature range 30−100 °C.