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dc.contributor.advisorDarensbourg, Donald
dc.creatorMackiewicz, Ryan Michael
dc.date.accessioned2006-08-16T19:06:14Z
dc.date.available2006-08-16T19:06:14Z
dc.date.created2003-05
dc.date.issued2006-08-16
dc.identifier.urihttp://hdl.handle.net/1969.1/3849
dc.description.abstractThe ability to utilize cheaper starting materials in the synthesis of commercially important materials has been a goal of scientists since the advent of the chemical industry. The ideal situation would be one in which by combining the correct proportions of hydrogen, nitrogen, carbon and oxygen that virtually anything from simple sugars to complex polymers could be produced. Unfortunately, such processes are flights of fancy often reserved for movies and television shows. On a more realistic level, the utilization of simple molecules and a transition metal catalyst has been a process that industry has exploited for many years. The most easily identifiable process is that for polyolefin production, that employs homopolymerization of simple monomers such as ethylene and catalysts ranging from Ziegler-Natta to metallocene type catalysts. On a more difficult level copolymerization reactions require a delicate balance between two competing reactions and as a result these reactions have been much less successful. For over a decade now the Darensbourg Research Laboratories have focused on utilizing another simple molecule: carbon dioxide. Carbon dioxide is a cheap, inert, nontoxic starting material that appears to be an ideal monomer. Although simplistic, CO2 is also very stable and its utilization in polymerization reactions have proven to be quite complex. In order for us to facilitate these reactions we employ both a transition metal catalyst and a comonomer. Epoxides act as an effective comonomer because the thermodynamic energy gained from breaking the strained three membered epoxide ring overcomes the stability of CO2 and allows the copolymerization reaction to occur. We have demonstrated a great deal of success with this process, most of which will be mentioned throughout this report. The majority of this dissertation will detail our use of salen complexes to optimize this copolymerization process, in order to further the use of CO2 as a viable source of C1 feedstock. Herein, I will illustrate how we have obtained more than a 100 fold increase in the rate of polymer formation as well as detailed mechanistic data that will provide a basis for future catalyst design studies.en
dc.format.extent2725696 bytesen
dc.format.mediumelectronicen
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherTexas A&M University
dc.subjectinorganicen
dc.subjectpolymeren
dc.subjectcopolymerizationen
dc.subjectCO2en
dc.subjectsalenen
dc.subjectchromiumen
dc.titleStructural and mechanistic studies into the copolymerization of carbon dioxide and epoxides catalyzed by chromium salen complexesen
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentChemistryen
thesis.degree.disciplineChemistryen
thesis.degree.grantorTexas A&M Universityen
thesis.degree.nameDoctor of Philosophyen
thesis.degree.levelDoctoralen
dc.contributor.committeeMemberCreasy, Terry
dc.contributor.committeeMemberDeRose, Victoria
dc.contributor.committeeMemberDunbar, Kim
dc.type.genreElectronic Dissertationen
dc.type.materialtexten
dc.format.digitalOriginborn digitalen


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