High Pressure and Molecular Weight Variation of Electrical Relaxation in Poly(Ethylene Oxide).
Abstract
Vacuum audio frequency complex admittance measurements have been performed on poly(ethylene oxide) using a fully automated dielectric spectrometer. Measurements have been made over the temperature range 5.5-320 K for molecular weights from 18,500 to 4,000,000. The gamma relaxation is essentially unchanged over the range of molecular weights studied. This represents evidence against assigning the gamma relaxation to the motion of end groups. Next, previously reported data for the gamma relaxation is reanalyzed using a reduced plot. The activation volume is found to be 3-4 cc/mol in good agreement with previous work and the small value implies that the relaxation is associated with the motion of very small segments of the polymer chain. Next, the relaxation associated with the glass transition, alpha subscript a , is only observed in temperature for some samples but is observed in both frequency and temperature for others. The strength of alpha subscript a decreases monotonically as molecular weight decreases. Finally, alpha subscript a was studied up to pressures of about 0.2 GPa for 5,000,000 molecular weight material. The results for the shift of alpha subscript a with pressure are in qualitative agreement with recent theories. Originator supplied keywords include: Solid electrolytes, polymer electrolytes, poly(ethylene oxide), electrical relaxation, high pressures, molecular weight.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1985
- Accession Number
- ADA157660
Entities
People
- John J. Fontanella
- M. C. Wintersgill
Organizations
- United States Naval Academy