Investigation of Ionically-Driven Structure-Property Relationships in Polyelectrolyte Networks
thesisposted on 2020-07-29, 20:08 authored by Jessica L SargentJessica L Sargent
Despite the abundant current applications for ionic hydrogels, much about the stimuli-responsive behavior of these materials remains poorly understood. Due to the soft nature of these materials, the number of traditional characterization methods which can be applied to these systems is limited. Many studies have been conducted to characterize bulk property responses of these materials, and experimental studies have been produced examining the distribution of free ions around single polyelectrolyte chains. However, little experimental work has been published in which molecular-scale interactions are elucidated in confined polyelectrolyte networks. Furthermore, the way in which responsive properties, other than bulk swelling capacity, scale with ionic fraction in mixed polyelectrolyte-non-polyelectrolyte hydrogel systems has not been thoroughly investigated.
The distribution and strength of polymer-counter-ion bonds has a remarkable effect on hydrogel properties such as absorption capacity, mechanical strength, and size and chemical selectivity. In order to tailor these properties for targeted applications in ionic environments, it is imperative that we thoroughly understand the character of these polymer-ion interactions and their arrangement within the bulk hydrogel. In order to do so, however, non-traditional methods of analysis must be employed.
This dissertation focuses on a model part-ionic hydrogel system, poly(sodium acrylate-co-acrylamide), in order to assess not only the polymer-counter-ion interactions but also the impact of gel ionic fraction on these interactions and the responses which they induce in gel performance properties. A model alkali (NaCl), alkaline earth (CaCl2), and transition (CuSO4) metal salt are employed to investigate changes in polymer properties from the macroscale to the nanoscale. The aim of this dissertation is to lay the foundation for the development of fundamental structure-property relationships by which we may fully understand the ionically-induced performance properties of polyelectrolyte networks.
NSF CMMI 1454360
Degree TypeDoctor of Philosophy
Campus locationWest Lafayette
Advisor/Supervisor/Committee ChairKendra A. Erk
Advisor/Supervisor/Committee co-chairJohn A. Howarter
Additional Committee Member 2Carlos J. Martinez
Additional Committee Member 3Jeffrey P. Youngblood
- Materials engineering not elsewhere classified
- Polymers and plastics
- Functional materials
- Inorganic materials (incl. nanomaterials)
- Macromolecular materials
- Structure and dynamics of materials
- Macromolecular and materials chemistry not elsewhere classified
- Physical properties of materials
- Condensed matter characterisation technique development
polymer chemistrypolymer physicspolyelectrolytehydrogelMaterials characterizationMaterials chemistryMaterials Engineering not elsewhere classifiedPolymers and PlasticsFunctional MaterialsChemical Characterisation of MaterialsMacromolecular and Materials Chemistry not elsewhere classifiedPhysical Chemistry of MaterialsSynthesis of MaterialsCondensed Matter Characterisation Technique Development