Abstract
Variable-temperature powder X-ray diffraction (VTXRD) and differential scanning calorimetry (DSC) have been used to determine the poly(ethylene oxide):Ca(CF3SO3)2 phase diagram. A new crystalline complex with a stoichiometry corresponding to 6 ether oxygens/Ca2+ ion has been identified. The data show that this complex exhibits a phase transition at approximately 200-degrees-C between a low temperature, alpha and high temperature, beta, polymorph; at higher temperature the beta polymorph melts incongruently. At lower salt contents, precipitation of Ca(CF3SO3)2 from the amorphous phase upon increasing the temperature is observed, indicating a negative entropy for the dissolution of the salt in the polymer. Finally, temperature dependent conductivities are presented for a range of compositions.
| Original language | English |
|---|---|
| Pages (from-to) | 1338-1343 |
| Number of pages | 6 |
| Journal | Chemistry of Materials |
| Volume | 5 |
| Issue number | 9 |
| Publication status | Published - Sept 1993 |
Keywords
- POLYMER ELECTROLYTES
- OXIDE)
- COMPLEXES