Chemistry Commons^™

Redox-Active Polymerization Catalysts And Their Applications, Nicholas M. Shawver

Masters Theses

Traditional catalyst systems are reliable means to produce polymers with well-defined architectures and thermomechanical properties; however, they are often limited by a narrow monomer scope and their ability access few, if any, advanced polymer architectures. To address this limitation, a new class of catalysts have recently emerged that feature redox-active moieties that may access advanced architectures through catalyst electronic modulation that arises from redox events occurring on the ligand scaffold or at the active metal center itself. For example, researchers have explored the ability of redox-active catalysts to impart “on-off” kinetic control during ring-opening polymerizations and their ability to access …

The Development Of Photoinduced Initiation Of Olefin Polymerization And Its Applications, Justin M. Burroughs

Doctoral Dissertations

Polyolefin synthesis is an ever-growing field due to the low cost of monomer feed stocks and the wide range of applications of the resulting polymeric material. Polyolefins are most commonly polymerized through coordination-insertion polymerization. One area this field of research has progressed is the development of complex ligand scaffolds to achieve various levels of control over polymerization. For example, researchers have been able to control molecular weight, branching density, and tacticity of various olefin polymerizations. As a result of complex ligand scaffolds, the catalytic systems become more expensive and less industrially applicable. On the other hand, little research efforts have …

Simplified Synthesis Of Conjugated Polymers Enabled Via 1,4-Dihydropyrrolo[3,2-B]Pyrrole, Kenneth-John Jack Bell

Master of Science in Chemical Sciences Theses

Conjugated polymers have attracted significant attention as the active layer material in organic electronics, such as organic photovoltaics and light-emitting diodes, partly due to the ability to influence a broad range of properties through structural design motifs. However, high performance conjugated polymers suffer from numerous synthetic steps, generation of toxic waste, and harsh reaction conditions all of which impart additional costs that inhibit their widespread utilization. Therefore, an emphasis on reducing synthetic complexity and utilizing abundant, commercially available starting materials is needed for organic electronics to reach their full potential. Dihydropyrrolo[3,2-b]pyrrole (H₂DPP) chromophores offer a simple one-pot synthesis …

Reversible Addition-Fragmentation Chain-Transfer Emulsion Polymerization And Its Application To Waterborne Coatings, Andrew Balgeman

Graduate Research Theses & Dissertations

Waterborne acrylic latex makes up a vast majority of the architectural coatings market, including most of the paints sold in retail stores. Most, if not all, of these latex formulations are prepared using radical polymerization of acrylic monomers. Reversible addition-fragmentation chain-transfer (RAFT) polymerization has been researched for over two decades, but to this point has made very little progress finding success in commercial applications. Indeed, a majority of RAFT research has been dedicated to successfully polymerizing different monomers with good degree of polymerization control, and very little research has been directed toward actual coating applications. In this study, we focused …

Advancements In Bio-Based Novel (Co)Monomers For Polymeric Materials, Khristal Anne Monroe

Electronic Theses and Dissertations

Most current research in the area of sustainable and environmentally friendly materials relate to the use of renewable sources for the fabrication of bio-based polymers and composites. Using plant-based derivatives is a common strategy. Pine sap can be distilled into turpentines (light fraction) and pine rosin (heavy fraction). Pine rosin is obtained as a brittle solid and its major component is abietic acid. This project aims at investigating a synthetic approach for the synthesis of a pine rosin-based polymer that can be potentially used for manufacturing a collection device for pine sap. The synthetic strategy consisted in the preparation of …

Direct Arylation Polymerization Of Indophenine-Based Monomers, Sarah Severson

Student Research, Papers, and Creative Works

Indophenine, a deep blue dye and a quinoidal compound, has shown potential as a monomer in donor-acceptor copolymer formation for use in energy and device applications. Despite the barrier of low solubility, we previously polymerized an indophenine-based monomer IQ to form PolyIQ-co-thiophene (PIQ) in a 95% yield using Stille coupling. Although PIQ has desirable electronic properties, Stille coupling is a particularly unsustainable method. In contrast, direct arylation polymerization (DArP) is a more sustainable polymerization method that reduces synthetic steps and toxic byproducts. Therefore, we now report the DArP of IQ to form PolyIQ-co-ProDOT (ProPIQ) in a 96% yield. ProPIQ boasts …

Hierarchical Conjugated Polymer Systems Prepared By Controlled Chain-Growth Polymerization, Chunwa Peter Kei

LSU Doctoral Dissertations

π-Conjugated polymer materials may have a significant economic impact on society by providing means for designing affordable, flexible, and portable organic electronic devices. Their successful commercialization will depend on major scientific advancements, which will challenge human society to seek out ever more detailed and fundamental processes to command. Controlled polymerization affords such a power; allowing for the design of meticulous and precisely defined systems granting detailed insight into structure-property relationships in the polymer materials and bettering understanding of novel physical phenomena.

This dissertation primarily focuses on development and preparation of well-defined hierarchically organized macromolecular systems. The novel chain-growth polymerization methodologies …

Development Of Highly Efficient Catalyst And Reactions For Organic Synthesis: Monophosphine-Coordinated Palladacycle Complexes For Cross-Coupling Reactions/Polymerizations, Jie Dong

Dissertations, Theses, and Capstone Projects

Transition metal-catalyzed cross-coupling reactions such as Suzuki-Miyaura cross-couplings, are among the most powerful transformations in organic synthesis. They have been extensively used for the synthesis of a wide variety of organic compounds. Recently the Suzuki cross-coupling reaction has been extended to conjugated polymer synthesis, especially the controlled Suzuki cross-coupling polymerization for polymers with the desired length. My research is on developing highly efficient monophosphine-coordinated palladacycle complexes for cross-coupling reactions/polymerizations.

Based on the understanding of transition metal-catalyzed Suzuki cross-coupling reactions including polymerization, my dissertation started with Pd(0)- and Ni(0)-catalyzed borylation reactions of aryl halides and tosylates with bis(pinacolato)diboron to access arylboronates …

Development Of Palladium(0)-Catalyzed Suzuki Cross-Coupling Polymerizations, Wei Peng

Dissertations, Theses, and Capstone Projects

The synthesis of well-defined and high molecular weight π-conjugated polymers under mild condition within short reaction time is a challenging and important task in both organic chemistry and polymer chemistry. As one of the most efficient and high tolerance to solvents and reaction conditions, palladium(0)-catalyzed cross-coupling reactions would give us a good chance to achieve the goal. Thus, my Ph. D dissertation research projects focused on developing Pd(0)-catalyzed Suzuki cross-coupling polymerization reactions including controlled ones.

My research first studied t-Bu₃P-coordinated 2-phenylaniline-based palladacycle complex catalyzed Suzuki cross-coupling polymerization of aryl dibromides with aryldiboronic acids at room temperature. Based …

Synthesis Of Dimeric Zinc Complexes For Use As Ring Opening Polymerization Catalysts, Kyle D. Brooks, Arnlold Rheingold, David B. Green, Joe Fritsch

Seaver College Research And Scholarly Achievement Symposium

No abstract provided.

Synthesis And Characterization Of Mpims : Metallopolymers Of Intrinsic Microporosity, Kelly Walter

Legacy Theses & Dissertations (2009 - 2024)

Polymers of intrinsic microporosity (PIMs) are class of polymers known for high surface areas arising from their contorted and rigid backbone structures. While high surface area compounds are applicable in many fields, simultaneous solubility and conductivity in PIMs is still lacking. In general, the monomeric units that form the backbone, necessary to yield inefficient polymer strand packing and contortion, also break conjugation in the along the polymer backbone and therefore limit conductivity. It has been previously noted that extended conjugation and the addition of metal atoms (along the backbone) increases conductivity. We therefore sought to use a strategy whereby the …

Optimizing Solvent Blends For A Quinary System, Thomas L. Hoy

Williams Honors College, Honors Research Projects

The Department of Polymer Engineering had received a grant from the Keck foundation to produce a process in which hundreds of copolymers can be formulated, synthesized, analyzed and then extrapolated to produce the optimal polymer for the desired material property. This process involves synthesizing approximately fifty polymers in a custom apparatus, none of which necessarily have the same monomer components. This leads to issue of which solvent or blend of solvents to use that would sufficiently dissolve both monomers and the resulting copolymer. If the monomers are not completely dissolved, a homogenous reaction will be impossible and if the copolymer …

The Effects Of Clay On Glycerol/Carboxylic Acid Polymerization: Implications Of Mineral Controls In Prebiotic Chemistry, Joseph T. Romero

Geology: Student Scholarship & Creative Works

Proto-enzymatic catalysis on early Earth is an important consideration in prebiotic chemistry research as it leads to the understanding of the emergence of the metabolic reaction networks. Contemporary enzymes are comprised of either organic or inorganic factors scaffolded by globular protein structure whereas we consider hyperbranched polyesters as a possible extant scaffold that is easier assembled than the peptide one. The goals of this project are to consider prebiotically plausible starting materials for such structure formation utilizing a subset of conditions for polymer synthesis involving the presence of mineral surfaces as well as temperature and hydration differential. As likely candidates …

Synthesis, Structure And Attempted Polymerization Of A Diepoxide Macrocycle, Paul Yarincik, Jeffrey H. Glans

Chemistry & Physics Faculty Publications

A novel diepoxide containing paracyclophane was synthesized by peracid oxidation of a known paracyclophane diene. The resulting diepoxide was characterized. It was investigated as a potential monomer for a cyclophane containing polyether by cationic ring opening polymerization. None of the standard catalyst systems for such a polymerization were successful in producing polymer.

The Synthesis Of New Maleimide Addition Polymer Precursors, Richard B. Brown

Chemistry & Biochemistry Theses & Dissertations

1H-2,3-dimethylpyrrolo(1,2-a) benzimidazol-l-one (27) and 1H,9H- 2,3,7,8-tetramethyl-bispyrrolo(1,2-a:6,7-a')benzodiimidazo1-1,9-dione (32) have been synthesized from dimethylmaleic anhydride and o-phenylenediamine and 1,2,4,5-tetraaminobenzene, respectively. The presence of reactive olefinic double bonds in the synthesized compounds was of interest as a site for possible addition polymerization.

The synthetic route involved, in both cases, a simple nucleophilic substitution reaction between the diamine(or tetraamine) and the anhydride to form an intermediate amide-acid-amine which rapidly cyclized to the imide amine. The final ring closure required more rigorous conditions and occurred at melt reaction temperatures.