The formation of crew-cut aggregates from polystyrene-b-poly(acrylic acid) (PS-b-PAA) copolymer in low alkanols (methanol, ethanol, iso-propanol and n-butanol) was investigated. The block copolymer employed has 390 PS units and 79 PAA units. The copolymer is solubilised upon heating and micellisation occurs as the temperature decreases: this preparation is referred to as the single-solvent method. Temperatures reached are above 120°C and thus require the use of pressure reactors as low alkanols have low boiling points. Three types of reactors were employed. The first was the unstirred reactor which validated the method. Secondly, a stirred reactor was used in order to maximise the dissolution of the copolymer over a broader range of conditions that achieved in the unstirred reactor. Micellisation induced on cooling is explained as being analogous to that encountered on adding a precipitant to a copolymer solution. The effects of stirring and pressure are also discussed. / Various morphologies were obtained in both reactors, including a highly ordered bicontinuous morphology in the stirred reactor. To determine the thermodynamics of the micellisation at high temperatures and elevated pressures, a reactor with windows was acquired. The set-up, interfacing and development of a more advanced instrument including this windowed reactor are described. Preliminary experiments showed that in-situ turbidity measurements can be carried out on this instrument; the results of these studies are also briefly reported. Finally, preliminary light scattering studies of polycaprolactone- b-poly(ethylene oxide) (PCL-b-PEO) copolymers of different compositions have been carried out. The dependence of the critical water content (cwc) on copolymer composition and concentration was studied and the results described.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.21541 |
| Date | January 1999 |
| Creators | Desbaumes, Luc. |
| Contributors | Eisenberg, Adi (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: 001654716, proquestno: MQ50756, Theses scanned by UMI/ProQuest. |
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