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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Monomer and polyimide production for radiation shielding purposes in manned space exploration /

Bate, Norah G. January 2009 (has links)
Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references (leaf 36). Also available via the World Wide Web.
42

Polymer-supported chiral lithium amide bases and structural investigation on bis(amino)boron enolates.

Ma, Lili. January 2008 (has links)
Thesis (Ph.D.)--Brown University, 2008. / Source: Dissertation Abstracts International, Volume: 69-06, Section: B, page: 3587. Adviser: Paul G. williard. Includes bibliographical references.
43

Synthesis of water-soluble polymers via atom transfer radical polymerisation

Ashford, Emma J. January 2000 (has links)
A study of the atom transfer radical polymerisation (ATRP) of water-soluble, acidic, monomers was carried out in aqueous media. The ATRP of sodium methacrylate (MAANa) produced polymers with controlled molecular weights and narrow polydispersities (Me/M, - 1.3) at 90°C. This is the first reported example of direct polymerisation of an acidic monomer via ATRP. Previously, such acidic polymers were produced by polymerisation of protected monomers. In this thesis, copper(l) bromide and iron(II) bromide were investigated as ATRP catalysts. Both were found to be effective when solubilised by 2,2'-bipyridine (bipy). Monomer conversions between 75 and 85 % were obtained in the presence of Cu(l)Brlbipy, and conversions as high as 94 % were obtained in the presence of Fe(II)Br2Ibipy. Kinetic studies carried out on the ATRP of MAANa using the CuBrlbipy catalyst and an oligo(ethylene glycol)-based initiator indicated that polymerisation proceeded via first order kinetics with respect to monomer consumption, and that molecular weight increased linearly with conversion. This is as expected for a living polymerisation. At approximately 75 - 85 % conversion, however, premature termination occurred. Both bromine microanalyses and 'n and 13CNMR studies indicated that the halide-capped polymer chain-ends undergo HBr elimination. Low molecular weight « 10,000 g mol") MAANa homopolymers and oligo(ethylene glycol)-sodium methacrylate block copolymers (PEG-b-PMAANa) were examined as possible macro initiators for the ATRP of sodium 4-styrenesulfonate (SSNa), potassium 3- sulfopropyl methacrylate (SPMAK) and sodium allyl sulfonate (SAS). PEG-b-PMAANa was found to initiate the ATRP of SSNa, yielding a polymer with controlled molecular weight and a polydispersity of 1.23. Initiation of the ATRP of SPMAK and SAS was less successful. This was likely due to the loss of functionality of the MAANa-based polymers. Block copolymers were obtained, however, by macroinitiating the aqueous ATRP of MAANa using a monomethoxy-capped oligo(ethylene glycol) methacrylate homopolymer. Successful ATRP of MAANa was also achievable at ambient temperatures in the presence of a co-solvent, 2-(dimethylamino)ethanol, DMAE. DMAE appears to dramatically increase the rate of polymerisation whilst still maintaining control when used in equimolar quantities (relative to the monomer). Polymers with predetermined molecular weights and narrow polydispersities were produced in good yield (up to 86 % conversion) within five minutes at 20°C. The ATRP of other hydrophilic monomers was also investigated, albeit in less detail. These monomers included sodium acrylate, mono-2-(methacryloyloxy)ethyl succinate, 2- hydroxyethyl acrylate, itaconic acid, and 2-acrylamido-2-methyl-propanesulfonic acid. Generally less control was achieved for such syntheses than for the ATRP of MAANa.
44

Synthesis of cationic macromonomers by living polymerizations for comb-branched polyelectrolytes /

Zeng, Faquan. January 2001 (has links)
Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references. Also available via World Wide Web.
45

Application of quantum mechanical QSAR to dental molecule design

Ye, Lin, Holder, Andrew J. January 2007 (has links)
Thesis (Ph. D.)--Dept. of Chemistry and School of Pharmacy. University of Missouri--Kansas City, 2007. / "A dissertation in chemistry and pharmaceutical science." Advisor: Andrew J. Holder. Typescript. Vita. Description based on contents viewed Apr. 15, 2008; title from "catalog record" of the print edition. Includes bibliographical references (leaves 89-93). Online version of the print edition.
46

Monomer recovery from nylon carpets via reactive extrusion

Bryson, Latoya G. January 2008 (has links)
Thesis (Ph. D.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Muzzy, John D.; Committee Member: Cook, Fred L.; Committee Member: Jones, Christopher W.; Committee Member: Mayor, J. Rhett; Committee Member: Realff, Matthew J.; Committee Member: Schork, F. Joseph.
47

A process for melt grafting itaconic anhydride onto polyethylene

Hanipah, Suhaiza Hanim. January 2008 (has links)
Thesis (M.E.)--University of Waikato, 2008. / Title from PDF cover (viewed August 26, 2008) Includes bibliographical references (p. 92-96)
48

Synthesis and properties of novel polyimides /

Zheng, Hai Bin, January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2001. / Includes bibliographical references. Also available in electronic format on the Internet.
49

Synthesis and characterization of norbornene-functionalized side-chain monomers for potential use as transport materials in organic light-emitting diodes

McClary, LaKeisha Michelle. January 2007 (has links)
Thesis (M.S.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2008. / Committee Chair: Marder, Seth; Committee Member: Bredas, Jean-Luc; Committee Member: Tolber, Laren. Part of the SMARTech Electronic Thesis and Dissertation Collection.
50

Accurate ab initio intermolecular potentials with a focus on monomer flexibility

Murdachaew, Garold. January 2005 (has links)
Thesis (Ph.D.)--University of Delaware, 2005. / Principal faculty advisor: Krzysztof Szalewicz, Dept. of Physics and Astronomy. Includes bibliographical references.

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