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dc.contributor.authorLi, Yien_US
dc.date.accessioned2014-03-14T20:38:35Z
dc.date.available2014-03-14T20:38:35Z
dc.date.issued2009-05-07en_US
dc.identifier.otheretd-05252009-021808en_US
dc.identifier.urihttp://hdl.handle.net/10919/33235
dc.description.abstractStilbene containing polymers are a group of interesting and versatile polymers. The pendent phenyl ring along the polymer backbone can impart unusual rigidity to the polymer backbone due to steric repulsion. By functionalizing stilbene, a variety of functional groups and ionic groups can be precisely placed along the polymer chain with tunable charge density. Therefore, stilbene containing polymers are potentially rod-like polyelectrolytes with controllable charges and charge density. They are the basis of a novel group of rigid synthetic polyelectrolytes and can be used for furthering our knowledge of rigid polyelectrolytes.

A novel series of methyl substituted stilbenes were synthesized and copolymerized with maleic anhydride. A conversion-time study was undertaken to understand the methyl substituent effect on copolymerization rates. Methyl substituted stilbene-maleic anhydride copolymer compositions were determined by quantitative 13C 1D NMR. SEC measurements showed the weight average molecular weights of these copolymers vary from 3 000 to over 1 000 000 g/mol. No glass transition temperature or crystalline melting temperature was observed between 0 oC and 250 oC by DSC. TGA showed that these polymers have 5% weight loss around 290 oC.

Precursors to a polycation and a polyanion based on functionalized stilbenes and maleimides have been prepared: poly(di-t-butyl-(E)-4,4â -stilbenedicarboxylate-co- N-(4-(t-butoxycarbonyl)phenyl)maleimide) and poly(N,N,Nâ ,Nâ -tetraalkyl-4,4â -di- aminostilbenes-co-N-4-(Nâ ,Nâ -dimethylaminophenyl)-maleimide). These copolymer precursors were characterized by 1H NMR, SEC, TGA, and DSC. The 1H NMR spectrum indicated the rigidity of copolymer backbones. SEC measurements showed the weight average molecular weights of these copolymers vary from 5 000 to 11 700 g/mol. No glass transition temperature or crystalline melting temperature was observed between 0 oC and 175 oC by DSC for poly(di-t-butyl-(E)-4,4â -stilbenedicarboxylate-co-N-(4-(t-butoxy- carbonyl)phenyl)maleimide). TGA showed that this polymer has 5% weight loss around 210 oC and 26% weight loss on the first stage of decomposition which corresponds to elimination of t-butyl functional group in the copolymer.

The homopolymerization of EMS-III via free radical polymerization, anionic polymerization and cationic polymerization was attempted. However, no polymer was obtained from any of these polymerization methods. In anionic polymerization, the solution changed to red upon the addition of the initiator sec-bu-Li, indicating the successful addition of the sec-bu-Li to EMS-III. However, the initiated monomer did not propagate to form homopolymer.

en_US
dc.publisherVirginia Techen_US
dc.relation.haspartYili_ThesisFinal1.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.subjectPolyelectrolytesen_US
dc.subjectHomopolymerizationen_US
dc.subjectAlternating Copolymerizationen_US
dc.subjectN-Phenyl substituted Maleimidesen_US
dc.subjectSubstituted Stilbenesen_US
dc.titleStudies Related to the Alternating Copolymerization of Substituted Stilbenesen_US
dc.typeThesisen_US
dc.contributor.departmentChemistryen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineChemistryen_US
dc.contributor.committeechairTurner, Sam Richarden_US
dc.contributor.committeememberLong, Timothy E.en_US
dc.contributor.committeememberRiffle, Judy S.en_US
dc.contributor.committeememberMarand, Hervé L.en_US
dc.contributor.committeememberDavis, Richey M.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05252009-021808/en_US
dc.date.sdate2009-05-25en_US
dc.date.rdate2010-01-26
dc.date.adate2010-01-26en_US


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