This dissertation describes the characterization of polystyrene- b-poly(acrylic acid) (PS-b-PAA) copolymer micelles by nuclear magnetic resonance spectroscopy (NMR). The segmental chain dynamics of the polystyrene-b-poly(acrylic acid) copolymer during the micellization process was investigated by solution-state proton NMR measurements. The spin-lattice and spin-spin relaxation parameters revealed the increased motional restriction of the PS blocks of the PS-b-PAA copolymer as aggregation was induced. The mobility of the PAA segments also decreased during the micellization process. However, the PAA blocks experienced greater motional freedom than the PS component forming the aggregate core. / 129Xenon NMR spectroscopy was used to determine the glass transition temperature of the PS core of the polystyrene-b-poly(acrylic acid) copolymer aggregates in dioxane/water mixtures. The temperature dependence of the NMR line shapes and resonance shifts of xenon in the PS and solvent phases of the PS-b-PAA copolymer micelles was analyzed. Discontinuities in the slope of the chemical shift-temperature curves for xenon sorbed in the PS component revealed phase transitions in the copolymer micelles. The PS core of the phase separated PS100-b-PAA 25 copolymer aggregates underwent the glass transition in the temperature region of 40°C to 45°C. The glass transition temperature of the PS core of PS218-b-PAA20 copolymer aggregates suspended in solution was in the 33°C to 35°C temperature region.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.32983 |
| Date | January 2001 |
| Creators | Chijiwa, Sachiko. |
| Contributors | Reven, L. (advisor), Eisenberg, A. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001845448, proquestno: MQ75293, Theses scanned by UMI/ProQuest. |
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