Suspensions of cellulose nanocrystals may be prepared by hydrolysing wood pulp or cotton filter paper with sulfuric acid. Due to the rod-like shape of the nanocrystals, these aqueous suspensions display liquid crystalline behaviour. This thesis examines these unique suspensions at three different concentration ranges. At low cellulose concentrations the suspensions are disordered, becoming ordered upon reaching a critical concentration, which depends on the aspect ratio of the rods. AFM and TEM were used to characterize particle size and polydispersity. Just beyond the critical concentration for anisotropic phase formation is an intermediate concentration range in which the isotropic and anisotropic phases co-exist. This biphasic region was examined for its potential to partition dextran molecules. At extremely high cellulose concentrations, solid cellulose films that maintain some chiral nematic order may be obtained. The degree of order in the films has been measured using induced circular dichroism and optimized by magnetic alignment. These suspensions can also be used to create model surfaces of cellulose I. The smooth cellulose surfaces have been characterized by XPS, X-ray diffraction, and AFM.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.37663 |
| Date | January 2002 |
| Creators | Edgar, Catherine D. |
| Contributors | Gray, Derek G. (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: 001956130, proquestno: NQ85702, Theses scanned by UMI/ProQuest. |
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