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dc.contributor.authorKrasznai, Danielen
dc.date2012-02-28 11:20:01.568
dc.date.accessioned2012-02-29T16:44:36Z
dc.date.available2012-02-29T16:44:36Z
dc.date.issued2012-02-29
dc.identifier.urihttp://hdl.handle.net/1974/7018
dc.descriptionThesis (Master, Chemical Engineering) -- Queen's University, 2012-02-28 11:20:01.568en
dc.description.abstractThe plant cell wall contains significant quantities of renewable polymers in the form of cellulose, hemicellulose, and lignin. These three renewable polymers have the potential to complement or replace synthetic polymers in a variety of applications. Rapidly determining the quantities of these polysaccharides in lignocellulosic biomass is important yet difficult since plant biomass is recalcitrant and highly variable in composition. Part of this contribution outlines a novel compositional analysis protocol using infrared spectroscopy and multivariate regression techniques that is rapid and inexpensive. Multivariate regression models based on calibration mixtures can be used to discern between populations of lignocellulosic biomass or to predict cellulose, hemicellulose, and lignin quantities. Thus, the compositional analysis step can be expedited so that other processes, like fractionation of the lignocellulose polymers, can be tuned accordingly to maximize the value of the final product. Hybrid materials were also generated using a variety of polymerization techniques and post-polymerization modifications. A novel controlled/living radical polymerization initiator was synthesized (2-bromo-2-methylpropane hydrazide) containing a hydrazide functionality that was covalently linked to the reducing-end of dextran. Despite the rapid coupling of the hydrazide- based initiator to the reducing-end of dextran, the instability of the alkyl bromide bond resulted in several unsuccessful attempts at Cu(0)-mediated controlled/living radical polymerization. Recommendations were given to improve the stability of this compound; however, an alternative approach to synthesizing hybrid copolymers was also investigated in parallel. Hyperbranched polymers were synthesized using commercially available vinyl and divinyl monomers in the presence of a cobalt(II) complex that enabled control over the size, architecture, and mol% of pendant vinyl groups amenable to post-polymerization modification. Modifying the ratio of divinyl monomer to cobalt(II) complex provided a series of hyperbranched polymers with variable morphology and mol% pendant vinyl groups. The pendant vinyl bonds were subsequently converted to amines via thiol additions with cysteamine. These amine functionalized hyperbranched polymers were then used in a subsequent reductive amination reaction with the reducing-end of dextran to produce the amphiphilic core-shell copolymer poly(methyl methacrylate-co-ethylene glycol dimethacrylate)-b-dextran. These amphiphilic copolymers mimicked the colloidal behaviour of conventional block copolymer micelles without requiring difficult syntheses or tedious self-assembly steps.en
dc.language.isoengen
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectMultivariateen
dc.subjectRenewableen
dc.subjectCCTPen
dc.subjectBiomassen
dc.subjectCRPen
dc.subjectLRPen
dc.subjectPLSen
dc.subjectCelluloseen
dc.subjectPolysaccharideen
dc.subjectLignocelluloseen
dc.subjectCu(0)en
dc.subjectHydrazideen
dc.subjectPCAen
dc.subjectCalibrationen
dc.subjectPolymeren
dc.titleMultivariate Characterization of Lignocellulosic Biomass and Graft Modification of Natural Polymersen
dc.typethesisen
dc.description.degreeM.A.Sc.en
dc.contributor.supervisorChampagne, Pascaleen
dc.contributor.supervisorCunningham, Michael F.en
dc.contributor.departmentChemical Engineeringen
dc.degree.grantorQueen's University at Kingstonen


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