Ion Transport, Viscoelastic, and Thermal Properties of Several Poly(Ethylene Glycol) and Poly(Propylene Glycol) Based Polymer Electrolytes
type: CreativeWork
description: This dissertation explores the relationship between ionic conductivity, viscosity, and thermal properties of several MePEG and MePPG based copolymer electrolytes. In particular two main copolymer modifications have been investigated namely copolymerization with "bulky groups" and cross polymerization of MePEG and MePPG monomers. The modifications were made to vary the fractional free volume of the MePEG polymers. All of the copolymers obeyed the Doolittle equation. For both the bulky copolymers and MePEG/MePPG copolymers, increases in the FFV corresponded to increases in the viscosity and decreases in FFV correspond to decreases in viscosity. The FFV and H+ conductivity for these copolymers were not correlated per the Forsythe equation. When the Vf,ether was substituted for FFV in the Forsythe equation, a strong correlation was observed indicating that the mechanism of proton conduction is dependent on the amount of ether units in the material. The viscosity and ionic conductivity for each individual copolymer electrolyte were correlated following the Walden rule. The ? values for all of the copolymer electrolytes were between 0.3 and 0.6 indicating that forces besides viscosity impede the ionic conductivity. These forces can include polymer rigidity, dissociation constant and the blocking of H+ channels. Most of the copolymer electrolytes had similar ? values which indicates that the same forces are affecting all of the copolymer electrolytes. The Cp shoa correlation to the activation energy for viscosity only for the MePPG3/MePPG2 copolymers. There was no correlation observed for all of the other copolymer electrolyte series. The correlation for the MePPG3/MePPG2 copolymers indicates that the molecular rearrangement in the material is dependent on the intermolecular forces present. There was no correlation observed between Cp and the activation energy for H+ conductivity for neither the high or low acid concentration MePEG/MePPG copolymers nor the low acid concent…
abstract: This dissertation explores the relationship between ionic conductivity, viscosity, and thermal properties of several MePEG and MePPG based copolymer electrolytes. In particular two main copolymer modifications have been investigated namely copolymerization with "bulky groups" and cross polymerization of MePEG and MePPG monomers. The modifications were made to vary the fractional free volume of the MePEG polymers. All of the copolymers obeyed the Doolittle equation. For both the bulky copolymers and MePEG/MePPG copolymers, increases in the FFV corresponded to increases in the viscosity and decreases in FFV correspond to decreases in viscosity. The FFV and H+ conductivity for these copolymers were not correlated per the Forsythe equation. When the Vf,ether was substituted for FFV in the Forsythe equation, a strong correlation was observed indicating that the mechanism of proton conduction is dependent on the amount of ether units in the material. The viscosity and ionic conductivity for each individual copolymer electrolyte were correlated following the Walden rule. The ? values for all of the copolymer electrolytes were between 0.3 and 0.6 indicating that forces besides viscosity impede the ionic conductivity. These forces can include polymer rigidity, dissociation constant and the blocking of H+ channels. Most of the copolymer electrolytes had similar ? values which indicates that the same forces are affecting all of the copolymer electrolytes. The Cp shoa correlation to the activation energy for viscosity only for the MePPG3/MePPG2 copolymers. There was no correlation observed for all of the other copolymer electrolyte series. The correlation for the MePPG3/MePPG2 copolymers indicates that the molecular rearrangement in the material is dependent on the intermolecular forces present. There was no correlation observed between Cp and the activation energy for H+ conductivity for neither the high or low acid concentration MePEG/MePPG copolymers nor the low acid concent…
author: Yancey, Benjamin Jacob
keywords: Conductivity, Free Volume Theory, Poly (Ethylene Glycol), Polymer Electrolyte, Viscosity, Chemistry
date published: 2011-01-01T08:00:00Z
date modified: 2026-07-24T03:05:22Z
provider: University of Mississippi
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Mississippi