Cascade poly(aryl ether) containing aryl sulfide or aryl sulfone groups, and aryl fluoride terminal functionality, were synthesized. Four generations of the dendrimers were prepared. The divergent initiator core method was employed, using 4,4$ sp prime$-difluorodiphenyl sulfone, as the core precursor, and a relatively high molecular weight phenol as the monomer. The strategy is based on an activation/condensation sequence that involves oxidation of the aryl sulfide group and the displacement of the activated aryl halide moiety by a phenolate ion. The aryl halide was activated by a sulfone group formed by oxidation of a sulfide group. / Optimum conditions for the condensation reaction utilized a very active metal carbonate, such as cesium carbonate, in conjunction with magnesium hydroxide or calcium carbonate which removes some of the fluoride ions formed. The phenolate was generated in situ from an organic carbonate, thus eliminating the usual dehydration step. NMR characterization indicated that the reactions were most quantitative and MALDI-TOF-MS confirmed those results up to the third generation. No reaction intermediates were detected. Imperfections in some molecules of the dendrimers, formed by reaction of the core precursors with an impurity present in the phenol, were also identified. / Simultaneously, aryl halide-terminated and phenol-terminated hyperbranched poly(ether sulfone)s were prepared by the polycondensation of A$ sb2$B monomers via a one-pot approach. Syntheses were developed for all the new monomers required. The main advantage of this method is its simplicity, which allows rapid access to large amounts of hyperbranched polymers. Molecular weights and viscosities were controlled by the concentration of the monomer and temperature of the reaction. The best conditions were obtained when the condensation agent was a mixture of $ rm Cs sb2CO sb3$ and Mg(OH)$ sb2$ and the displaced halide was a fluoride.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.39962 |
| Date | January 1995 |
| Creators | Martínez, Coromoto |
| Contributors | Hay, A. S. (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 | Doctor of Philosophy (Department of Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001484218, proquestno: NN12432, Theses scanned by UMI/ProQuest. |
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