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dc.contributor.authorLane, Ozma Redden_US
dc.date.accessioned2014-03-14T20:49:09Z
dc.date.available2014-03-14T20:49:09Z
dc.date.issued2011-11-18en_US
dc.identifier.otheretd-12082011-172023en_US
dc.identifier.urihttp://hdl.handle.net/10919/36016
dc.description.abstractProton exchange membrane fuels cells (PEMFCs) are one of the primary alternatives to internal combustion engines. The key component is the proton exchange membrane, or PEM, which should meet a number of requirements, including good proton conductivity under partially humidified conditions. A number of alternative PEMs have been synthesized by copolymerizing various aromatic comonomers, but the smaller ion channels prohibit rapid proton transport under partially hydrated conditions. One solution has been to synthesize multiblock copolymers from hydrophilic and hydrophobic oligomers to ensure sufficient ion channel size. Four multiblock systems were synthesized from hydrophobic and hydrophilic oligomers and were characterized in this thesis. The first multiblock system incorporated a partially fluorinated monomer into the hydrophobic block, to improve phase separation and performance under partially humidified conditions. The second study was focused on phase separation and structure-property relationships as a function of casting conditions of a biphenol-based multiblock series. The third study featured a novel hydroquinone-based hydrophilic oligomer in the multiblock copolymer, which showed the promise of a higher ionic density, degree of phase separation and proton conductivity values. The fourth study in this thesis entailed the comparison of a block copolymer produced with two distinct synthetic routes: the multiblock synthesis from separate oligomers as previously published in the literature, and a segmented route seeking to achieve comparable structure-property relationships with the same monomers, but using a simpler synthetic route. The two block copolymer series were found to be comparable in their structure-property relationships.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartLane_O_T_2011.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectproton exchange membraneen_US
dc.subjecthydrogen fuel cellen_US
dc.subjectmultiblock copolymersen_US
dc.subjectproton conducting materialsen_US
dc.titleCharacterization of Structure-Property Relationships in Hydrophilic-Hydrophobic Multiblock Copolymers for Use in Proton Exchange Membrane Fuel Cellsen_US
dc.typeThesisen_US
dc.contributor.departmentMacromolecular Science and Engineeringen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeechairMcGrath, James E.en_US
dc.contributor.committeememberRiffle, Judy S.en_US
dc.contributor.committeememberDillard, John G.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-12082011-172023/en_US
dc.date.sdate2011-12-08en_US
dc.date.rdate2012-01-10
dc.date.adate2012-01-10en_US


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