Audio frequency electrical conductivity and relaxation studies have been carried out on Parel 58 elastomer and Parel 58 elastomer complexed with a variety of lithium salts. The measurements have been carried out in vacuum over the temperature range 5–380 K and at pressures up to 0.65 GPa over the temperature range 230–380 K. Both the electrical conductivity for the complexed material and the electrical relaxation time associated with the α relaxation in the uncomplexed material exhibit VTF or WLF behavior. From a VTF analysis for both the vacuum electrical relaxation time and electrical conductivity, Ea is found to be about 0.09 eV and T0 is found to be about 40 °C below the ‘‘central’’ glass transition temperature. In addition, it is found that the activation volumes for the electrical relaxation time and the electrical conductivity are the same when compared relative to T0. These results imply that the mechanism controlling ionic conductivity is the same as that for the α relaxation, namely large-scale segmental motions of the polymer chain.

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The 1000-Hz 300°K dielectric constants were measured for crystalline α-quartz, sapphire, MgF2, and MgO, and polycrystalline sapphire (Lucalox), magnesium fluoride (IRTRAN 1), and magnesium oxide (IRTRAN 5). The measurements were performed using the method of substitution (two-fluid method). The results are as follows: single-crystal α-quartz, εs∥=4.6368±0.001 and εs⊥=4.5208±0.001; single-crystal sapphire, εs∥ = 11.589±0.005 and εs⊥=9.395±0.005; polycrystalline sapphire (Lucalox), εs=10.154±0.007; single-crystal MgF2, εs∥ =4.826±0.01 and εs⊥=5.501±0.01; polycrystalline MgF2 (IRTRAN 1), εs=5.289±0.001; single-crystal MgO, εs=9.830 ±0.001; and polycrystalline MgO (IRTRAN 5), εs=9.833±0.001, where εs∥ and εs⊥ are the dielectric constants parallel and perpendicular, respectively, to the c axis.

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A substitution method for highly accurate determination of the static dielectric constant of solids is presented along with techniques for refining capacitance measurements. The results for some alkaline earth fluorides are CaF_: 6.799, SrF 2 : 6.466, and BaF,: 7.359, and an alkali halide, KC1, is: 4.818.