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Kim, Young-Min MacGregor John Frederick. "Photopolymerization of cycloaliphatic epoxide and vinyl ether /." *McMaster only, 2005.
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Kirschbaum, Stefan [Verfasser]. "Vinyl ether functional polyurethanes as novel photopolymers / Stefan Kirschbaum." Mainz : Universitätsbibliothek Mainz, 2017. http://d-nb.info/1125907592/34.
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Pietri, Valerie. "Electron beam irradiation of polystyrene/poly(vinyl methyl ether) blends." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-07292009-090349/.
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Gestoso, Souto Patricia. "Orientation study of poly(vinyl phenol)/poly(vinyl methyl ether) blends by infrared dichroism and molecular dynamics." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65420.pdf.
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Lang, Weihong. "Synthesis of oligo (vinyl ether)s in ab initio cationic polymerisation." Thesis, University of Sheffield, 2002. http://etheses.whiterose.ac.uk/10205/.
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Terminally functionalised oligo(vinyl ether)s were produced in ab initio cationic polymerisations. Various polymerisations and chain end functionalisation systems were investigated. MALDI-TOF mass spectrometry was applied to analyse the obtained oligomers and thus the polymerisation and chain end functionalisation process. Oligo(isobutyl vinyl ether), also oligo(ethyl vinyl ether) and oligo(methyl vinyl ether) were synthesised in cationic polymerisation. Silyl enol ethers were added to the polymerisation as end-capping agents before initiations and they compete with monomer to cap the carbocationic chain end. The methodology relies on a comparable end capping rate to chain propagation rate so that oligomers can still be produced in the presence of reactive end-capping agents whilst other side reactions are suppressed. Polymerisation temperatures investigated range from -78°C to the room temperature (21 °C), 4 out of 6 silyl enol ethers were applied and are proved to be reactive in the end-capping. Initiation systems investigated include iBVEHCl/Yb(OTf)3 and iBVE-HCl/SnC14 and both produced oligomers with high chain end functionalities. Generally silyl enol ether functionalised oligo(vinyl ether)s have lower molecular weights and broader molecular weight distributions than their identical control polymerisations without end-capping. The iBVE-HCl/SnCI4 initiation system produced functionalised oligomers with narrower molecular weight distribution than iBVE-HCl/Yb(OTf)3 initiation system. Different silyl enol ether reactivities in end-capping were observed. It was also observed that ab initio chain end functionalisation by reactive silyl enol ethers largely suppressed the majority of side reactions during polymerisation. This suppression was attributed to the higher rates of end-capping than side reaction rates. When (1-tert-butyl-vinyloxy)trimethyl-silane was applied as end-capping agent, the polymerisation system produced oligomers with narrower molecular weight distributions than the control polymerisations without end-capping while the chain end functionalities were also obtained. This indicates the possibility of setting up a controlled ab initio chain end functionalisation cationic polymerisation system in which the oligomer's molecular weight, polydispersity and chain end functionality can be regulated at the same time. MALDI-TOF MS, NMR and SEC are mainly applied in the oligomer characterisation. Side reactions in this polymerisation system were examined from these analyses. Under less critical polymerisation conditions 7 different chain ends from side reactions are observed in MALDI-TOF mass spectra. Based on the MS and NMR observation the various chain end structures are identified. Side reactions are also postulated which mainly include ß-proton elimination, water capping of the carbocationic chain end and combinations of these. Sample preparation for MALDI-TOF MS analysis of oligo(vinyl ether)s is investigated. Direct laser desorption of oligo(isobutyl vinyl ether) was observed for the samples of molecular weight of up to 2k Daltons. Complementary information of oligo(isobutyl vinyl ether)s obtained from ESI MS indicates a serious mass discrimination in MALDI-TOF MS technique and thus it is regarded that MALDITOF MS can not provide reliable molecular weight distributions for polymers with broad molecular weight distributions. Combination of SEC and MALDI-TOF MS to calibrate SEC columns and quantitative application of MALDI-TOF MS to analyse the oligomers' chain end functionalities were also explored.
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Kalita, Deep Jyoti. "Polymers and Coatings Derived From Novel Bio-Based Vinyl Ether Monomers." Diss., North Dakota State University, 2018. https://hdl.handle.net/10365/27852.
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To fulfill the demand for household, industrial, light weight transportation, health, and cosmetic products etc., production of polymeric materials has been increasing every year. However, limited resource of fossil fuel is threatening the sustainability of the raw materials used to produce these products. These products have very low to no biodegradability, thereby staying in the ecosystem for long time causing serious threats. Increasing environmental concerns and strict regulations has made renewable based materials suitable for the development of environmental friendly polymers with sustainability. Novel plant oil based vinyl ether (POVE) monomers were derived from plant oil such as soybean, linseed and camelina oil. Polymers varying in molecular weight (MW) were derived from these monomers and studied for air-drying coatings. Study of the coating and free film properties showed that at a given MW, Tensile (Young’s modulus, and tensile strength), viscoelastic (Tg, XLD), physical (hardness, solvent resistance, and impact resistance) properties increased with increasing unsaturation in the parent PO. Polymers derived from distilled POVE monomers resulted essentially colorless poly(POVEs) which were evaluated as a binder for artist paint in comparison to linseed oil. Colorless poly(POVE)s showed significantly faster dry/cure along with dramatically lower yellowness than linseed oil. Novel, vinyl ether monomers, were also synthesized from cardanol (CEVE) and eugenol (EEVE) and coatings produced from their homopolymers and copolymers with cyclohexyl vinyl ether were studied in comparison to commercial alkyds. Glass transition temperatures of these homopolymers were increased with CHVE incorporation. However, incorporation of 25% CHVE resulted in cured coatings and free films with better mechanical, viscoelastic and physical properties than commercial alkyds. Incorporation of CHVE > 50wt.% in the copolymer resulted in low crosslinked networks with reduced properties such as percent elongation, chemical resistance and impact resistance. Epoxidized poly(EEVE) resins varying in percent epoxide (30%, 50% and 70%) were synthesized and studied for two component amine cured coatings in comparison to BPA based epoxy resin. Results obtained from high throughput experimentation showed the ability of Epoly(EEVE) resins with 50% or higher epoxide to form harder, higher crosslinked coatings with tunability based on type of curative than BPA based resin.National Science Foundation EPSCoR Program (grant IIA-1355466)
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Kleissler, Charles Richard. "Comparison of poly(vinyl alcohol) backbone-grafted ethers and chain-growth crown ether polymers in selective cation adsorption." Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/10115.
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Ohgi, Hiroyuki. "Studies on Synthesis and Physical Properties of Highly Isotactic Poly(vinyl alcohol) Derived from Poly(tert-butyl vinyl ether)." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/57290.
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Chang, Teng. "Studies of Genistein Modified Poly(Ether Sulfone)/Poly(Vinyl Pyrrolidone) and Poly(Vinyl Chloride)/Epoxidized Soybean Oil Blends with Enhanced Blood-Compatibility for Biomedical Application." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1427712989.
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Lea, Santa Cinzia Chemical Sciences & Engineering Faculty of Engineering UNSW. "An investigation into the synthesis of poly(co-maleic anhydride/iso-butyl vinyl ether)with RAFT polymerisation." Awarded by:University of New South Wales. Chemical Sciences and Engineering, 2006. http://handle.unsw.edu.au/1959.4/31435.
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Poly (co iso-butyl vinyl ether-alt-maleic anhydride), an alternating copolymer, was synthesised. For this class of copolymers the formation of an electron-donor complex is invoked to explain their microstructure in which the two comonomers strictly alternate. Due to its polarity, this copolymer constitutes a potential additive for imparting hydrophilic properties to a hydrophobic matrix. In order to obtain narrow molecular weight polymers and study the relation between the molecular weight of this additive and its ability to migrate to the host polymer surface, chain transfer agents were introduced in the system and also the Reversible Addition-Fragmentation chain Transfer (RAFT) process was employed. Free radical polymerisation was first carried out to allow for a comparison with the RAFT process and kinetics of copolymerisation was studied by NIR-FTIR and 1H NMR spectroscopy in order to analyse the rate of reaction of each comonomer. Dibenzyl trithiobenzoate, 3-benzyl sulfanyl thiocarbonyl sulfanyl-propionic acid and dibenzyl trithiobenzoate were used as RAFT agents. Results demonstrate that only benzyl dithiobenzoate is able to control the molecular weight of this copolymer and decrease its polydispersity index; possible reasons laying behind this result are discussed. It was also found that, in particular in the presence of benzyl dithiobenzoate, poly(iso-butyl vinyl ether) forms. This is an unusual phenomenon considering that the free radical polymerisation affords alternating copolymers and that iso-butyl vinyl ether is a monomer that polymerises through the cationic process. Experiments were carried out in various solvents in an attempt to counteract this side reaction, but no appreciable correlation between the properties of the solvents and the formation of homopolymer were found. Various hypothesis are considered, however it is likely that, in the conditions adopted, the presence of the RAFT agents alters the equilibrium constant of complex formation favouring the synthesis of the homopolymer. In addition to this side???reaction also inhibition of the copolymerisation reaction was at times encountered and an investigation into this phenomenon was also conducted.
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Souza, Ligia Elene [Verfasser]. "Poly(vinyl methyl ether-alt-maleic anhydride) based nanoparticles and nanocapsules : formulation and characterization / Ligia Elene Souza." Halle, 2017. http://d-nb.info/1155173295/34.
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Bronk, John M. "Synthesis and characterization of poly (butyl vinyl ether) homopolymers and copolymers utilizing the aluminum hydrogen sulfate catalyst system." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040347/.
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Iftene, Fadela. "Nouveaux monomères et (co)polymères éthers vinyliques phosphonés." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2012. http://www.theses.fr/2012ENCM0006/document.
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L'objectif de cette thèse est de synthétiser de nouveaux monomères éthers vinyliques porteurs de groupements phosphonate, dans le but d'étudier leur efficacité comme retardateurs de flamme. Les produits phosphorés s'avèrent de bonnes alternatives aux retardateurs de flamme halogénés, qui présentent des problèmes environnementaux. Dans un premier temps, nous avons réalisé la synthèse des éthers vinyliques phosphonés par transéthérification de l'éthylvinyl éther en présence d'alcools phosphonés. Ensuite, nous avons choisi la copolymérisation radicalaire (A/D) afin de préparer des copolymères à base d'éthers vinyliques phosphonés et de différents accepteurs. Des études cinétiques par Infra-Rouge en temps réel et plusieurs méthodes d'analyses ont été effectuées afin de caractériser ces copolymères. Dans un second temps, nous avons réalisé des cinétiques de photocopolymérisation radicalaire du 2-vinyloxyéthylphosphonate de diméthyle avec une série de monomères accepteurs, par exemple, les maléimides avec qui ce monomère forme des complexes forts. La photopolymérisation cationique a aussi été réalisée et offre de meilleurs résultats que la photopolymérisation radicalaire. Un bilan de tous les polymères phosphonés a été réalisé dans le but de tester leurs performances en tant que retardateurs de flamme. Les caractérisations thermogravimétriques et microcalorimétriques de ces copolymères ont montré une quantité importante de résidus et des valeurs de chaleur dégagée encourageantes en vue d'une utilisation de ceux-ci en tant que retardateurs de flammeThe aim of this work is the synthesis of new vinyl ethers monomers bearing phosphonate groups, in order to study their efficiency as flame retardants. Phosphorus products are known to be a good alternative to halogenated flame retardants, which are involved in environmental problems. Initially, the synthesis of phosphonated vinyl ethers was performed by trans-etherification of ethylvinyl ether in the presence of phosphonated alcohols. Then, the radical copolymerization (A/D) was used to prepare copolymers based on phosphonated vinyl ether and various electron-accepting monomers. Kinetic studies by real-time Infrared and several methods of analyzes were used to characterize these copolymers. In a second step, the radical photocopolymerization of 2-dimethylvinyloxyethylphosphonate was led with a series of electron-accepting monomers, for instance maleimides which form strong complexes with vinyl ethers. The cationic photopolymerization of these phosphonated vinyl ethers is also possible and affords better results than radical photopolymerization. An assessment of all phosphonated polymers was performed in order to test their performances as flame retardants. Thermogravimetric and microcalorimetric characterizations showed good amount of released residues showing that these copolymers are good candidates as flame retardants
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Haraldsson, Klas Tommy. "Fabrication of polymeric microfluidic devices via photocurable liquid monomers." Doctoral thesis, Stockholm : Fibre and Polymer Technology, Department of Chemical Engineering and Technology, Royal Institute of Technology (KTH), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-466.
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Yaacoub, Saly. "Etude de couches hybrides photopolymérisables de type vinyl éther silane : Application à la fabrication de composants optiques intégrés." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20175/document.
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Depuis plusieurs dizaines d'années, les matériaux hybrides organiques-inorganiques constituent une classe de matériaux particulièrement bien adaptée aux applications en optique intégrée. Le réseau minéral, élaboré par procédé sol-gel, confère au matériau la tenue mécanique. Quant au réseau organique, qui est réticulable par voie photochimique, il permet la formation des systèmes guidants. Des travaux antérieurs réalisés au sein de notre laboratoire ont montré le potentiel d'un matériau à base d'un précurseur hybride 2-(3,4 epoxycyclohexylethyltrimethoxysilane) (EETMOS) pour l'application en optique intégrée. Bien que la qualité des composants réalisés à 1,31µm se soit révélée satisfaisante, un problème subsiste : une trop forte atténuation à 1,55 µm. La transmission optique autour de ces longueurs d'ondes est limitée par la présence des groupements OH et CH aliphatiques.L'objectif principal de ce travail est de développer une nouvelle génération de matériaux hybrides avec une très grande réactivité et de diminuer la quantité de groupements impliqués dans l'atténuation. Nous avons choisi la fonction vinyl éther comme fonction organique grâce à sa grande réactivité par voie cationique en comparaison avec la fonction époxyde. Nous avons étudié la double fonctionnalité de polymérisation du nouveau matériau hybride à base d'un vinyl éther silane. En premier lieu, les réactions d'hydrolyse et de polycondensation du sol ont été suivies par la spectroscopie RMN liquide du Si-29 en fonction du temps, de la température et du pH de l'eau impliquée dans l'hydrolyse. Le but était d'obtenir le plus haut taux d'oligomère multifonctionnel possible et le minium de groupement OH. La photopolymérisation de type cationique de la fonction vinyl éther a ensuite été étudiée, en utilisant la spectroscopie d'absorption dans l'infrarouge moyen. En présence du photoamorceur diaryliodonium, la photopolymérisation a été étudiée en suivant l'évolution de la bande d'absorption de la double liaison vinyl éther avant et après irradiation. La photopolymérisation cationique est rapidement initiée dès le début de l'exposition aux UV, ce qui prouve la réactivité important de la fonction vinyl éther. En utilisant la spectroscopie d'absorption dans le proche infrarouge, les résultats montrent des niveaux d'atténuation très prometteurs pour l'utilisation de ce matériau en optique intégré à 1,31 et 1,55 µmIn the last few years, organic-inorganic hybrid materials were particularly attractive for integrated optical circuits. Hybrid network could be prepared by the formation of inorganic and organic network simultaneously through sol-gel technique and photopolymerization process.A composition based on [2-(3, 4 epoxycyclohexylethyltrimethoxysilane)] has already allowed the fabrication of optical integrated devices. The organic polymerization is on a cationic way. Results show the contributions of OH and aliphatic CH groups to the attenuation in the third telecommunication window located at 1,55 µm.The main objective of this work is to remove this difficulty by developing a new generation of hybrid materials with a very high reactivity and low amount of groups involved in the attenuation. We have chosen vinyl ether function as an organic part because of their well known high polymerization rates via cationic way which are faster than the epoxide function and which lead to no OH groups generation and a very low aliphatic CH groups introduction.In this work, we study the dual functional structure of a new vinyl ether alkoxysilane hybrid precursor. Firstly, hydrolysis and polycondensation of vinyl ether based solution are followed by liquid and solid Si-NMR spectroscopy. The kinetic reaction is followed as a function of time, temperature and pH of the water involved in the hydrolysis, in order to obtain the highest reactive multifunctional oligomer and the lowest OH groups. Secondly, results of the cationic photopolymerization of vinyl ether- based monomers are also reported, using middle infrared spectroscopy. In the presence of diaryliodonium photoinitator, the photopolymerization is studied by monitoring the absorption band of vinyl ether double bond before and after irradiation. The cationic photopolymerization occurs rapidly upon UV-exposure and vinyl ether monomers proved to be very effective monomers. Using near infrared spectroscopy, results show promising attenuation for the use of this material in integrated optic at 1,31 µmand 1,55 µm
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Datta, Gopal K. "Heck Reactions with Aryl Chlorides : Studies of Regio- and Stereoselectivity." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9202.
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Ben, Ayed Achich Kawther. "Synthèse énantiosélective d'aminoacides disubstitués polyfonctionnels via cycloaddition dipolaire d'α-carboxy cétonitrones." Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1013/document.
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Lors de ces travaux de thèse, nous nous sommes intéressés au développement de deux voies différentes de cycloaddition dipolaire-1,3 (CD-1,3) asymétrique pour accéder à des acides aminés disubstitués polyfonctionnels nouveaux de façon stéréochimiquement contrôlée.Dans la première partie, nous avons réalisé l’étude de la cycloaddition dipolaire-1,3 diastéréosélective entre différentes nitrones fonctionnelles et différents éthers vinyliques chiraux. La CD-1,3 de la cétonitrone aspartique et de l’éther vinylique du (R) ou (S) stéricol s'opère avec un double contrôle diastéréochimique élevé. Ce contrôle est possible en raison de la stabilité de la nitrone sous une forme (E) qui favorise l’approche exo, facialement contrôlée par le dipolarophile. La N-déprotection chimiosélective de l'adduit fournit une isoxazolidine sous une forme diastéréo- et énantiomériquement pure qui peut être transformée en dérivé d’acide aminé après N-acylation et coupure de la liaison N-O selon un processus dismutatif.Dans la deuxième partie, nous avons réalisé une étude approfondie de la cycloaddition dipolaire-1,3 organocatalysée entre différentes cétonitrones dérivées d’acides aminés vis-à-vis de dipolarophiles pauvres en électrons de type énal ou ynal. Avec le (E)-crotonalldéhyde, de hautes diastéréo- et énantiosélectivités sont obtenues en présence du catalyseur de MacMillan. Cette réaction organocatalysée a été étendue à une variété de d'α-carboxy cétonitrones différemment substituées, ainsi qu'à différents énals β-substitués par un groupement alkyle moyennant une modification de la nature du co-acide. En revanche, les ynals ne montrent aucune réactivité vis à vis des cétonitrones en conditions organocatalytiques. Notre étude a été complétée par l’accès des dérivés d’amino-acides polyhydroxylés par ouverture des adduits obtenus par la voie énantiosélective en utilisant les énals comme dipolarophiles. Cette étude préliminaire permet d’envisager d’accéder à des analogues de la myriocineDuring this thesis, we were interested to develop two different ways of 1,3 dipolar cycloaddition to reach enantiopure disubstituted polyfunctionnal amino acids.We have described in a first part the diastereoselective 1,3-dipolar cycloaddition between an aspartic nitrone and chiral vinyl ethers. The aspartic ketonitrone and vinyl ether of (R) or (S) stericol led to high diastreocontrols. This control is due to the stability of the nitrone under (E) geometry which favors the exo approach, facially controlled by the dipolarophile. The chemoselective N-deprotection of this adduct leads to a diastereo- and enantiomerically pure isoxazolidine which affords the target DAA after N-acylation and N-O ring opening by a dismutative pathway. In a second part, we describe the synthesis of isoxazolidines obtained by organocatalytic enantioselective 1,3-dipolar cycloaddition between an alanine-derived nitrone and an enal or an ynal as the dipolarophile. With enals β-substituted by alkyl groups, good diastereoselectivities and ees were obtained in the presence of the MacMillan catalyst. These organocatalyzed conditions can be applied to a range of carboxy ketonitrones, and to different enals, provided an appropriate choice of the co-acid. Ynals show no reactivity under these organocatalytic conditions, although they lead regioselectively to polyfunctional quaternary isoxazolines under thermal conditions.Our study was achieved by the access of polyhydroxylated amino acids derived from opening adducts obtained by the enantioselective route using enals as dipolarophiles. This study allows to envisage the enantioselective synthesis of analogs of myriocin
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Goetz, Lee Ann. "Preparation and analysis of crosslinked lignocellulosic fibers and cellulose nanowhiskers with poly(methyl-vinyl ether co maleic acid) â " polyethylene glycol to create novel water absorbing materials." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45893.
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The search for cellulosic based products as a viable alternative for petroleum-based products was the impetus for covalently crosslinking lignocellulosic fibers and nanocellulose whiskers with poly(methyl vinyl ether) co maleic acid (PMVEMA) - polyethylene glycol (PEG). The lignocellulosics used were ECF bleached softwood (pine) and ECF bleached birch kraft pulp. This thesis also tests the hypothesis that water absorption and retention can be improved by grafting PMVEMA-PEG to the surface of ECF bleached kraft pulp hardwood and softwood fibers via microwave initiated crosslinking. The crosslinking of the PMVEMA to hardwood and softwood kraft ECF bleached pulp fibers resulted in enhanced water absorbing pulp fibers where the PMVEMA is grafted onto the surface of the fibers. The crosslinking was initiated both thermally and via microwave irradiation and the water absorption and water retention was measured as the percent of grafted PMVEMA. This was the first application of microwave crosslinking of pulp fibers with the goal of creating water absorbing pulp fibers. Ultimately, the water absorption values ranged from 28.70 g water per g dry crosslinked pulp fiber (g/g) to 230.10 g/g and the water retention values ranged from 26% to 71% of the water retained that was absorbed by the crosslinked pulp fibers. The microwave initiated crosslinked fibers had comparable results to the thermally crosslinked fibers with a decreased reaction time, from 6.50 min (thermal) to 1 min 45 sec (microwave).
Cellulose nanowhiskers, crystalline rods of cellulose, have been investigated due to their unique properties, such as nanoscale dimensions, low density, high surface area, mechanical strength, and surface morphology and available surface chemistry. Prior to this study, the crosslinking of cellulose whiskers with the matrix via solution casting of liquid suspensions of whiskers and matrix had not been explored. The hypothesis to be investigated was that incorporating cellulosic whiskers with the PMVEMA-PEG matrix and crosslinking the whiskers with the matrix would yield films that demonstrate unique properties when compared to prior work of crosslinking of PMVEMA-PEG to macroscopic ECF bleached kraft pulp fibers.
Solution cast composites of cellulose nanowhiskers-PMVEMA-PEG were crosslinked at 135 °C for 6.5 min and analyzed for crosslinking, thermal stability, strength and mechanical properties, whisker dispersion, and water absorption and uptake rates. The whisker-composites demonstrated unique properties upon crosslinking the whiskers with PMVEMA-PEG, especially the elongation at break and tensile strength upon conditioning of the final materials at various relative humidities. In addition, the whiskers improved the thermal stability of the PMVEMA-PEG matrix. This is significant as methods of improving processing thermal stability are key to developing new materials that utilize cellulose whiskers, PMVEMA, and PEG. This thesis addresses the hypothesis that cellulose nanowhiskers that are crosslinked with a matrix can create new whisker-matrix composites that behave differently after crosslinking.
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Trejos, Alejandro. "Palladium-Catalysed Couplings in Organic Synthesis : Exploring Catalyst-Presenting Strategies and Medicinal Chemistry Applications." Doctoral thesis, Uppsala universitet, Avdelningen för organisk farmaceutisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-173068.
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Palladium-catalysed coupling reactions have been embraced by synthetic chemists as one of the preferred means for smooth formation of new carbon-carbon bonds: a truly ubiquitous methodology of synthesizing complex molecules. This thesis describes the study of a series of palladium(0)-catalysed C2-arylations of a 1-cyclopentenyl ether, equipped with a chiral (S)-N-methyl-pyrrolidine auxiliary. The investigated olefin was demonstrated to undergo Si-face insertion, providing (R)-configuration of the arylated C2-carbon. In addition, the mild and novel palladium(II)-catalysed dominoHeck/Suzuki β,α-diarylation-reduction of a dimethylaminoethyl-substituted chelating vinyl ether was developed using arylboronic acids as arylating agents in combination with 1,4-benzoquinone (BQ). Further, highly regioselective palladium(II)-catalysed α-and β-monoarylation of the chelating vinyl ether was achieved using either a bidentate ligand or by employing ligand-less conditions. These studies demonstrate that the choice of ligands has a profound effect on the reaction outcome, as productive β,α-diarylation could only be obtained by suppressing the competing β-hydride elimination using BQ as the stabilising ligand and terminal reoxidant. The pivotal role of BQ in the reaction was studied using computer-aided density functional theory calculations. The calculations highlight the crucial role of BQ as a Pd(II)-ligand. In addition of serving as an oxidant of palladium, the calculations support the view that the coordination of BQ to the Pd(II)-centre in the key σ-alkyl complex leads to a low-energy pathway, aided by a strong η2 Pd-BQ donation-back-donation interaction. Furthermore, an investigation of the scope and limitations of novel stereoselective and BQ-mediated palladium(II)-catalysed domino Heck/Suzuki β,α-diarylation reactions, involving metal coordinating cyclic methylamino vinyl ethers and a number of electronically diverse arylboronic acids, conducted. In addition, a set of 4-quinolone-3-carboxylic acids, structurally related to elvitegravir and bearing different substituents on the condensed benzene ring, was designed and synthesized as potential HIV-1 integrase inhibitors. Finally, in an effort to identify a new class of HIV-1 protease inhibitors, four different stereopure β-hydroxy γ-lactam-containing inhibitors were synthesized, biologically evaluated, and co-crystallized with the enzyme.The time 12:05 for the public defense mentioned in the thesis is incorrect. It will take place at 09:15, 2012-06-08.
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Joo, Minjung. "Silane terminated macromonomers with nanoparticles and surface segregation of fluorinated moieties." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1478876813425998.
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Hamdi, Abdelrahman. "Asymmetric Synthesis of Oxaproline-Based Tripeptides Analogs of Asunaprevir and their Biological Evaluations." Thesis, Le Mans, 2020. http://www.theses.fr/2020LEMA1020.
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L’’ infection par le virus de l’ hépatite C (HCV) est considérée comme un des défis majeurs de santé publique en Egypte où la prévalence du virus de 10 % est la plus élevée au monde selon l’EHIS (Enquête sur les Problèmes de Santé en Egypte). Dans les récents développements thérapeutiques de nouveaux médicaments anti-HCV, une gamme d’inhibiteurs de protéase actifs a déjà été approuvée dans le traitement de l’HCV dans plusieurs pays (asunaprévir, paritaprévir, grazoprévir). Ces membres de la famille “prévir” ont en commun une structure tripeptidique équipée d’une unité 4-hétéroarylproline centrale. Notre travail de thèse s’est donné comme objectif de préparer deux nouvelles séries d’analogues potentiellement actifs comme anti-HCV. Ceux-ci impliquent le remplacement isostérique du cycle de la proline par un cycle isoxazolidine et l’introduction d’un groupe en position 4 de type heteroaryloxy- ou -CH2-. Les précurseurs des oxaprolines ont été synthétisés de novo avec une stratégie par cycloaddition 1,3-dipolaire (1,3-DC) impliquant une carboxynitrone et une vinyloxy/ allyl quinoline. L’unité oxaproline obtenue a été deprotégée séquentiellement (groupes N- et CO2H) et couplée jusqu’à l’obtention des tripeptides visés. Notre travail inclut deux domaines de la recherche méthodologique en chimie organique : (i) l’accès à des isoxazolidines très fonctionnelles par 1,3-DC avec la difficulté du diastéréocontrôle avec des aldonitrones et la sensibilité en milieu acide de ces composés et (ii) la synthèse et le couplage de dérivés d’acides aminés optiquement actifs non-naturels et difficile à faire. Des tests biochimiques et cellulaires ont été effectués sur les analogues formésHepatitis C virus (HCV) infection is considered the most challenging public health problem in Egypt where the prevalence is the highest in the world. Recent survey known as the Egyptian Health Issues Survey (EHIS) reported a prevalence of 10% HCV infection. In the recent therapeutical development of new anti-HCV drugs, a variety of active protease inhibitors have been already approved for treatment of HCV in some countries (asunaprevir, paritaprevir, grazoprevir). These members of the "previr" family display a common structure based on a tripeptide featuring a central 4-heteroarylproline unit. Our PhD work involves the attempts to prepare two new series of anti-protease analogues as novel anti-HCV agents. These analogues involve isosteric replacement of proline ring by isoxazolidine ring and introduction of either a heteroaryloxy or a heteroaryl-CH2- appendage at the C4 position. The oxaproline precursors have been de novo synthetized using an asymmetric 1,3-dipolar cycloaddition (1,3-DC) strategy, that involves the reaction between a vinyloxy / allyl quinoline and a carbalkoxynitrone. The obtained oxaproline unit have been subjected to sequential deprotection of N- and CO2H groups, and amide couplings to afford the target tripeptide analogues. Our work includes two domains of methodologic research in organic chemistry: (i) the access of highly functional isoxazolidines by 1,3-DC with the difficulty of diastereocontrol with aldonitrones and the acid sensitivity of these compounds (ii) the synthesis and the coupling of optically active non-natural and «difficult to make» amino acid derivatives. Both biochemical and cell-based assays have been done for the formed analogues
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Dawkins, David Anthony. "Asymmetric synthesis using chiral vinyl ethers." Thesis, University of Leicester, 1992. http://hdl.handle.net/2381/33644.
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Using chiral alcohol precursors, a number of chiral vinyl ethers were prepared by mercuric acetate-catalysed transetherification with butyl vinyl ether. a-Lithiation of (1R)-menthyl vinyl ether was unsuccessful under a variety of conditions. (1S)-(Menthylthio)ethene was prepared from (1S)-menthanethiol but deprotonation was not possible as the thioether was found to decompose rapidly at room temperature. The deprotonation of (R)-phenethyl vinyl ether, (S)-l-(2-naphthyl)-l-ethyl vinyl ether and (S)-l-phenyl-1-butyl vinyl ether and attempted reaction with benzaldehyde yielded none of the a-alkylated adduct but a Wittig rearrangement reaction was seen. The cycloaddition reaction of benzonitrile oxide with a range of chiral vinyl ethers was investigated. The isoxazoline product was isolated as a mixture of two diastereoisomers after flash column chromatography. In most cases the diastereoisomer ratio neared 1:1, but (S)-l-(2-naphthyl)-l-ethyl vinyl ether and 1-phenyl-1-butyl vinyl ether gave a single diastereoisomer of the isoxazoline product, after chromatography, with a variety of nitrile oxides. Conditions have been developed for the removal of the chiral auxiliary but as yet only achiral isoxazolines have been obtained by this method. Attempts at ring deprotonation/alkylation and also the addition of a nucleophile or radical to the isoxazoline C=N bond were hindered by the instability of the isoxazoline adducts. A chiral vinyl pyrrolidinone was also prepared and found to undergo an asymmetric cycloaddition reaction with benzonitrile oxide to yield a single diastereoisomer of the isoxazoline product. The equivalent acrylamide was synthesised and, although this gave a 1:1 mixture of diastereoisomers with both benzonitrile oxide and 2,2-dimethylpropanenitrile oxide, these diastereoisomers could be separated. Removal of the chiral auxiliary yielded hydroxyisoxazolines with an enantiomeric excess of 90-94%. Attempts to investigate the extent of any asymmetric induction in the cycloaddition of nitrile oxides to chiral vinyl sulphoxides were hampered by the instability of the isoxazoline product, which underwent an immediate syn-elimination. In an effort to determine the potential of chloromethyl-(1R)-menthyl ether as a chiral OH protecting group, a series of (1R)-menthoxymethyl ethers were prepared from a variety of racemic and homochiral alcohols. Conditions for deprotection were developed which did not lead to the racemisation of homochiral alcohols. The usefulness of the (1R)-menthoxymethyl ether group as a simple means of measuring enantiomeric excess was demonstrated in a silicon-directed diene synthesis.
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Forder, Clive. "Water-soluble block copolymers via living cationic polymerisation." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318608.
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Bovell, Ivor. "The synthesis and photochemistry of propenyl and vinyl ethers." Thesis, University of Kent, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411945.
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Moss, Neil. "Divinylcyclopropane rearrangements : preparation of tricyclic ring systems and a formal total synthesis of (±)-quadrone." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25942.
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The first section of this thesis describes three model studies involving the synthesis of the divinylcyclopropanes (135), (136), and (137) and the subsequent thermal rearrangement of these compounds to provide the interesting tricyclic compounds (139), (140), and (141). [Formula Omitted] The second section of this thesis describes a formal total synthesis of the antitumor sesquiterpenoid (±)-quadrone (34). The synthesis is based on the chemistry developed in the model studies and involves the thermal rearrangement of the divinylcyclopropane (304) as the key step. The resulting product, compound (305), is- subsequently elaborated into the keto aldehyde (230), and since compound (230) has previously been converted into (t)-quadrone (34) by Burke and coworkers,¹⁰¹ the isolation of (230) comprises a formal total synthesis of the sesquiterpenoid. [Formula Omitted] The third section of this thesis describes a study involving the facile vinylmethylenecyclopropane rearrangement of enolates derived from various 7-exo-vinylbicyclo[4.1.0]heptan-2-ones.Science, Faculty of
Chemistry, Department of
Graduate
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Cho, Chang Gi. "Controlled polymerization of alkyl vinyl ethers via 'covalent' propagating species." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53930.
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The study of the polymerization of alkyl vinyl ethers initiated by HI/I₂ catalyst is directed into two areas: the kinetics of the polymerization and the strategy of amine functionalized prepolymer synthesis.
The polymerization reactions show living behavior in nonpolar solvents at low temperatures. The observed rate of polymerization under reaction conditions is linearly dependent on the initial concentration of hydrogen iodide and iodine, respectively. However, the monomer concentration does not influence the rate of polymerization(apparent zero-order). Two possible reaction schemes are proposed from the observed rate equation and attempts are made to distinguish them by using UV/visible spectroscopy and carbon-13 NMR spectroscopy. In both schemes a reversible interaction between a monomer and an iodine molecule is postulated as a necessary elemental reaction to fit the observed expression for the rate of polymerization. From spectroscopic analysis results, the interaction between the iodide compound(chain end) and the iodine molecule seems to be very weak compared to the interaction between the monomer and the iodine molecule.
A synthetic strategy for amine functionalized prepolymer synthesis has been developed via a series of model reactions. Incorporation of a styrenic monomer at the propagating chain end of living poly(alkyl vinyl ethers) provides a convenient intermediate synthesis of a relatively stable amine functionalized prepolymer. Proper selection of substituents at the styrenic monomer optimizes the cross addition reaction and amination reactions. Linear alkylamines with lower carbon numbers are used in the amination reaction in order to promote the nucleophilic substitution reaction and to minimize possible elimination reactions. A series of amine functionalized oligomers are synthesized by employing the synthetic strategy in combination with the previous kinetic result of the homopolymerization. For oligomers, incorporation of a few units of ethyl vinyl ethers at the chain end facilitates the cross addition reaction. Synthesized amines are characterized by various spectroscopic methods. Then, titrated molecular weights show good agreement with their theoretical molecular weights in several cases.Ph. D.
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Pollex, Annett. "Viridiofungins and xeniolide F: target oriented synthesis using different rearrangement reactions of a common substrate class." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1160474365794-44380.
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The present dissertation covers the total synthesis of viridiofungin triesters and studies toward the total synthesis of xeniolide F. In both cases, sigmatropic rearrangements of α-allyloxy substituted α,β-unsaturated esters are employed: for the viridiofungin ester synthesis a [2,3]-Wittig rearrangement and for the xeniolide F synthesis a catalytic asymmetric Claisen rearrangement CAC. For both rearrangement reactions the historical development, main characteristic and important variations are discussed. The viridiofungin triester synthesis represents a convergent and highly flexible route toward these natural products. The [2,3]-Wittig rearrangement allowed the diastereoselective synthesis of the polar head group with two adjacent stereogenic centers. The E-configured double bond was formed by a Julia-Kocienski olefination. During the studies toward the total synthesis of xeniolide F a new, diastereoselective strategy for the generation of allyl vinyl ethers with E-configured vinyl ether double bond was established employing rhodium catalyzed OH-insertion and an E-selective Horner-Wadsworth-Emmons olefination. Under the conditions of the catalytic asymmetric Claisen rearrangement (CAC) this highly substituted allyl vinyl ether rearranged diastero- and enantioselectively to the corresponding a-keto ester. This example clearly illustrates the high potential of the CAC as synthetic tool for natural product synthesisIn der vorliegenden Arbeit wird die Totalsynthese von Tirestern der Viridiofungine A, A2 und A4 sowie die Synthese eines Schlüsselintermediates für die Totalsynthese von Xeniolid F dargestellt. In beiden Fällen wird ausgehend von einem α-allyloxysubstituierten α,β-ungesättigten Ester eine Umlagerungsreaktion als Schlüsselschritt eingesetzt: im Falle der Viridiofunginester eine diastereoselektive [2,3]-Wittig-Umlagerung, bei den Arbeiten zur Totalsynthese von Xeniolid F eine diastero- und enantioselektive, katalytische Claisenumlagerung. Für beide Umlagerungsreaktionen werden ausführlich die theoretischen Hintergründe sowie die historische Entwicklung und wichtige Varianten besprochen. Mit der Viridiofungintriestersynthese wird eine konvergente und bezüglich der lipophilen Seitenkette sehr flexible Syntheseroute vorgestellt. Die [2,3]-Wittig-Umlagerung konnte dabei erfolgreich für die diastereoselektive Synthese der hochsubstituierten, polaren Kopfgruppe der Viridiofunginester mit zwei benachbarten stereogenen Zentren (davon eines quartär) eingesetzt werden. Zur Bildung der E-konfigurierten Doppelbindung wurde die Julia-Kocienskie-Olefinierung ausgenutzt. Bei den Arbeiten zur Totalsynthese von Xeniolid F wurde eine neuartige Strategie zur diastereoselektiven Synthese eines Allylvinylethers mit E-konfigurierter Vinyletherdoppelbindung eingesetzt. Die Horner-Wadsworth-Emmons-Olefinierung (HWE-Olefinierung) generierte dabei E-selektiv die Vinyletherdoppelbindung. Das für die HWE-Olefinierung benötigte Phosphonat wurde durch rhodiumkatalysierte OH-Insertion aus einem Allylalkohol und einem Diazaphosphonoacetat hergestellt. Der hochsubstituierte Allylvinylether wurde unter den Bedingungen der katalytisch asymmetrischen Claisenumlagerung umgesetzt und führte mit exzellenter Diastereo- und Enantioselektivität zum entsprechenden α-Ketoester. Anhand dieses Beispiels konnte das Potential der katalytisch asymmetrischen Claisenumlagerung zum Aufbau von hochfunktionalisierten Bausteinen für die Naturstoffsynthese verdeutlicht werden
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Pichavant, Loïc. "Design, synthèse et réactivité de monomères issus de ressources renouvelables pour la polymérisation radicalaire." Reims, 2009. http://theses.univ-reims.fr/exl-doc/GED00001124.pdf.
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L’utilisation de la biomasse comme source de matière première renouvelable constitue une alternative jugée économiquement et écologiquement prometteuse pour obtenir de nouveaux polymères de synthèse. Les voies possibles sont néanmoins très nombreuses. Elles méritent d’être explorées et évaluées par des études approfondies en vue de retenir les options les plus pertinentes. Dans le cadre de la valorisation d’agro-ressources, la synthèse de monomères éther de vinyle et éther d’allyle à partir de monosaccharides a été envisagée. Le design de nouveaux monomères non conventionnels passe par la connaissance de la réactivité de modèles simples. Dans un premier temps, l’étude de monomères monofonctionnels en copolymérisation radicalaire de type donneur-accepteur photo-amorcée a été réalisée en utilisant des monomères alkylés simples et en modifiant progressivement la structure jusqu'à l’étude de dérivés de sucre. La bonne réactivité de ces modèles ainsi que la relation entre la structure et la réactivité ont été montrées, avec notamment l’augmentation de la vitesse de copolymérisation avec la présence de liaisons physiques fortes. Les copolymères obtenus par cette voie ont été caractérisés en terme de microstructure (composition, enchaînement, extrémités de chaînes) permettant la mise en évidence des mécanismes réactionnels. La bonne connaissance de la réactivité de ces modèles a ensuite permis l’étude de la réactivité de monomères allylés polyfonctionnels afin d’obtenir des matériaux organiques par la formation de réseaux tridimensionnels. Les propriétés physiques de ces matériaux ont pu être caractérisées et ont laissées entrevoir d’éventuelles applicationsThe use of biomass as a source of renewable raw material is an economically and environmentally promising alternative for new synthetic polymers. Numerous ways are possible for the same. These ways shall be explored and evaluated in detail in order to retain the most relevant options. The synthesis of vinyl and allyl ether monomers from carbohydrates has been proposed to upgrade agro-resources. The knowledge on the reactivity of simple models is essential for designing new nonconventional monomers. To begin with the study of monofunctional monomers in a photoinitiated donor-acceptor radical copolymerization was performed by using simple alkylated monomers. This was followed by gradually modifying the structure of these monomers to study the corresponding sugar derivatives. The good reactivity of these chemical moeties and the relationship between the structure and reactivity has been demonstrated. An increased copolymerization rate due to presence of physical interactions was also observed. The copolymers thus obtained, have been characterized in terms of their microstructure (i. E. Composition, chaining, chain-endings) to investigate the reaction mechanisms. A good knowledge of the reactivity of these models allowed the study of the reactivity of the polyfunctional allyl monomers and obtains organic materials by formation of threedimensional networks. Physical properties of these materials have been characterized and the results are promising to enable their role in possible applications
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Dejean, de La Batie Rémi. "Etude des mouvements moléculaires dans les polymères en masse par résonance magnétique nucléaire du 13c et simulation de Monte-Carlo." Paris 6, 1986. http://www.theses.fr/1986PA066284.
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Etude des mouvements locaux dans le polyvinylmethylether, le polybutadiene-1,4cis et le polyisoprene-1,4cis, le polyisobutène, les polyéthers en masse; polyoxypropylène et réseaux de polyoxyéthylène, influence de la microstructure sur les mouvements moléculaires locaux. Etude de la transition vitreuse dans les polymères en masse par simulation de Monte-Carlo dynamique; simulation de systemes de polymères places dans le réseau tétraédrique et simulation de systemes de sphères libres et de systemes de polymères en milieu continu.
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Yan, Zhiqing. "Theoretical and Experimental Studies of the Lithiation of Cyclic Vinyl Ethers in Gas Phase and Ethereal Solutions." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1091024241.
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Abe, Masahiro. "Etude de la réactivité d'ynolethers et ynamines arylogues pour des réactions d'hydroamination. Etude visant la synthèse énantiosélective de la molécule koumine." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR062.
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Le noyau pipéridine est un des motifs les plus courant dans les produits naturels et pharmaceutiques ce qui explique que la synthèse énantiosélective de piperidines polyfonctionnalisées soit un domaine particulièrement dynamique. De par sa capacité à associer une fonction amine à un groupement carbonylé, la réaction de Mannich est un outil efficace pour former une liaison C-C de manière énantiosélective tandis que la réaction d’hydroamination intramoléculaire d’alcynes est pratique pour construire des hétérocycles azotés par formation de liaisons C-N. Dans cette thèse, nous avons combiné ces deux stratégies pour former de manière concise et énantiosélective des pipéridines polysusbstituées. Un couplage énantiosélectif de Mannich anti-sélectif fut employé pour préparer des amines chirales contenant une fonction alcyne connectée à un noyau aromatique riche en électrons. En présence d’acide de Brønsted, une réaction d’hydroamination cyclisante eut lieu démontrant une réactivité arylogue d’ynolethers et d’ynamines, la régiosélectivité de la cyclisation dépendant fortement de la densité électronique de l’alcyne. Ainsi lorsque la densité électronique est insuffisante, des pyrrolidines à cinq chainons furent obtenus tandis que lorsque la densité électronique est élevée des piperidines furent isolées, illustrant la passage d’une activation de triple liaison par liaison hydrogène à sa protonation. A partir des tetrahydropyridines et piperidines, une étude fut lancée dans le but d’achever la première synthèse totale énantiosélective du produit naturel koumine, un alcaloïde de type GelsemiumPiperidine ring is one of the most common heterocycles in natural products and the motif is especially well represented in pharmaceuticals. Consequently, enantioselective synthesis of multi-substituted piperidines is an important topic of investigation. For the synthesis of nitrogen-containing compounds, asymmetric Mannich coupling is a useful strategy while intramolecular hydroamination of alkynes is a practical route to construct N-heterocyclic products. In this thesis, the two strategies were combined. anti-Selective enantioselective Mannich reactions were thus employed to prepare chiral arylalkynyl amines. Connected to various aromatics, the reactivity of the triple bond was then studied in the framework of the intramolecular hydroamination reaction promoted with Brønsted acid. It was shown that depending on the electronic density of the alkyne, these adducts were converted into 5- or 6-membered rings, highlighting the balance between H-bonding and protonation. Tetrahydropyridines and piperidines were thus obtained with high regio-, diastereo-, and enantioselectivity and further functionalizations were also investigated in view of the first enantioselective total synthesis of Gelsemium alkaloid koumine
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郭富超 and Fu-chiu Kwok. "A systematic study of heterocyclic keto-enol tautomerism and the observation of mechanistic change in the hydrolysis of someheterocyclic vinyl ethers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31230908.
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Kwok, Fu-chiu. "A systematic study of heterocyclic keto-enol tautomerism and the observation of mechanistic change in the hydrolysis of some heterocyclic vinyl ethers /." [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1234560X.
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Ngono, Bernadette. "Organométalliques à carbonyle masqué : quelques propriétés du lithio-1 triméthylsiloxy-2 éthylène." Rouen, 1989. http://www.theses.fr/1989ROUES021.
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La condensation du lithio-1 triméthylsiloxy-2 éthylène avec les chlorotrialkylsilanes et le triflate de t-butyldiméthylsilyle conduit aux éthers d'énols silyles -silyles. L'hydrolyse acide de ces derniers permet d'isoler le t-butyldiméthylsilyl acétaldéhyde. D'autre part, la condensation du lithio-1 triméthylsiloxy-2 éthylène avec les chlorures d'acides non énolisables conduit a des esters d'énols de -cétoaldéhydes
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Guerre, Marc. "Synthèse et Auto-assemblage de Copolymères Fluorés Amphiphiles Deeper insight into the MADIX Polymerization of Vinylidene Fluoride A Journey into the Microstructure of PVDF Made by RAFT Limits of vinylidene Fluoride RAFT Polymerization One-pot Synthesis of Poly(Vinylidene Fluoride) Methacrylate Macromonomer via thia-Michael addition RAFT synthesis of well-defined PVDF-b-PVAc block copolymers Combination of cationic and radical RAFT polymerization: A versatile route to well-defined poly(vinyl ethyl ether)-block-poly(vinylidene fluoride) block copolymers Amphiphilic poly(vinylidene fluoride)-b-poly(vinyl alcohol) block copolymer: Synthesis and Self-Assembly in water Polymerization-induced Self-Assembly of PVAc-b-PVDF block copolymers via RAFT dispersion polymerization of VDF in dimethylcarbonate." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2017. http://www.theses.fr/2017ENCM0006.
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Les polymères fluorés constituent une classe de polymères à part, aux propriétés remarquables (résistance chimique et thermique, ferroélectricité et piézoélectricité lorsqu‟ils sont semicristallins pour en citer quelques-unes). Les polymères fluorés ont trouvé de nombreuses applications industrielles. Toutefois, ils n‟ont pas encore attiré tout l‟intérêt qui leur est dû de la part de la communauté scientifique. Il reste en effet difficile de préparer des architectures polymères fluorées bien définies. Les techniques de synthèse développées et utilisées jusqu‟à présent permettent la synthèse d‟architectures polymères intéressantes, mais elles souffrent de deux inconvénients majeurs : 1) Elles ne permettent pas d‟accéder à de hautes masses molaires, et 2) les architectures obtenues ne sont pas bien définies. En conséquence, les études physiques de ségrégation de phases en films ou en masse, et ou bien celles qui portent sur la cristallisation des polymères fluorés ont été limitées aux homopolymères et aux mélanges. De même, il existe très peu de travaux sur l‟auto-assemblage d‟architectures polymères fluorées en solution. A travers une étude cinétique approfondie, des caractérisations détaillées en spectroscopie (NMR) ainsi que des calculs DFT, cette étude a révélé la remarquable éfficacité de la RAFT pour synthétiser des architectures de PVDF bien définies. L‟auto-assemblage de blocs PVDF-b-PVA ainsi que l‟autoassemblage induit par la polymérisation de copolymères PVAc-b-PVDF ont dévoilé les premières nanostructures de type coeur/coquille et rose des sables à base de PVDFFluoropolymers constitute a specific class of polymers, with remarkable properties (high resistance to chemicals and heat, ferroelectricity and piezoelectricity for semi-crystalline polymers, to name a few). Fluoropolymers have found many industrial applications. However, fluoropolymers have not yet attracted all the interest they deserve from the scientific community. It is indeed difficult to prepare well-defined fluorinated polymeric architectures. The synthesis techniques developed and used so far allow the preparation of interesting architectures, but they suffer from two major drawbacks: 1) They do not allow access to high molar mass, and 2) The resulting architectures are ill-defined. As a result, physical chemistry studies of the phase segregation phenomena in films or in the bulk, or of the crystallization of fluorinated polymers were for the most part limited to homopolymers and blends. Similarly, very few studies of the self-assembly in solution of fluorinated polymeric architectures have been reported. Throughout deeper kinetic study, NMR characterizations and DFT calculation, this study reveals the remarkable efficiency of the RAFT polymerization to synthesize well-defined PVDF–based architectures. Self-assembly of PVDF-b-PVA block copolymers as well as polymerization-induced self-assembly of PVAc-b-PVDF block copolymers led to the first crystalline core/shell and desert-rose PVDF-based nanostructures
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Honoré, Jean-Claude. "Conception et synthèse de nouveaux acétals de cétènes cycliques pour l’obtention de polyesters aliphatiques fonctionnalisés." Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0045.
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Les polyesters aliphatiques représentent l’une des familles de polymères les plus utilisées à ce jour dans de nombreux domaines. Leurs propriétés de (bio)dégradation en font des matériaux très intéressants pour des applications environnementales ou biomédicales. Obtenus traditionnellement par polycondensation, biosynthèse ou polymérisation par ouverture de cycle (ROP), ces procédés ne permettent pas aisément la réalisation de matériaux cumulant dégradabilité et propriétés des polymères issus de monomères vinyliques. L’utilisation de monomères spécifiques, les acétals de cétènes cycliques (CKA), permet par la polymérisation radicalaire par ouverture de cycle (r-ROP) d’obtenir des polyesters aliphatiques avec des propriétés de dégradation intéressantes. Ce travail de thèse a consisté en la conception de polyesters aliphatiques biodégradables et fonctionnels. Pour cela, nous avons montré qu’il est possible d’obtenir aisément ces polyesters aliphatiques fonctionnels par copolymérisation des CKA avec les éthers de vinyles (VE) présentant des fonctions d’intérêts et synthétisés au préalable. De plus, l’utilisation d’éthers de divinyle commerciaux a permis l’obtention de matériaux (bio)dégradables réticulés présentant des propriétés mécaniques et biologiques compatibles avec une application en ingénierie tissulaire, et notamment en thérapie cardiaqueAliphatic polyesters represent one of the most widely used families of polymers in many fields. Their (bio)-degradation properties make them very interesting materials for environmental or biomedical applications. Obtained traditionally by polycondensation, biosynthesis or by Ring-Opening Polymerization (ROP), these processes do not easily allow the realization of materials combining degradability and properties of polymers derived from vinyl monomers. The use of specific monomers, Cyclic Ketene Acetals (CKA), allows by Radical Ring-Opening Polymerization (r-ROP) to obtain aliphatic polyesters with interesting degradation properties.This PhD work consist in the design of biodegradable and functional aliphatic polyesters. For this, we first showed that it is possible to easily obtain these functional aliphatic polyesters by copolymerization of CKA with vinyl ethers (VE) having functions of interest and synthesized beforehand. Then, the use of commercial divinyl ethers has made it possible to obtain crosslinked (bio)-degradable materials having mechanical and biological properties compatible with an application in tissue engineering, and in particular in cardiac therapy
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Denys, Goument Colombe. "Dicétones-1,4 thiosubstituées." Rouen, 1988. http://www.theses.fr/1988ROUES023.
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Lin, Hui-Fen, and 林慧棻. "Study of the UV-initiated cationic polymerization of vinyl ether." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/91941040092825856534.
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Kim, Chol-han. "Thermochemistry of vinyl alcohol and vinyl ether radical and kinetic analysis of neopentyl radical reaction with molecular oxygen." Thesis, 2002. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2002-006.
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Rema, B. "Studies Of Moisture-induced Crosslinking in Some Novel Vinyl Ether-Maleic Anhydride Copolymers and Terpolymers And Synthesis And Characterization Of Hyperbranched Polyketals." Thesis, 1999. http://etd.iisc.ernet.in/handle/2005/1660.
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Huang, Zheng-Shan, and 黃丁山. "The syntheses of azulene derivatives by the reaction of 2H-cyclohepta [ b ] furan-2-ones with vinyl ether and vinyl acetates." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/72142215866384143423.
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Chiang, Wan-Jing, and 蔣宛菁. "Effects of Poly(vinyl methyl ether) on Phase Morphology in Blends Comprising Biodegradable Polyesters." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/77926870645651589616.
Full textAbstract:
碩士國立成功大學
化學工程學系碩博士班
95
Various phase behavior of blends of poly(vinyl methyl ether) (PVME) with a series of polyesters with different ratios of aliphatic carbons to ester groups were examined using differential scanning calorimetry (DSC) and optical microscopy (OM). Effects of varying the main-chain polarity of the constituent polyesters on the phase behavior of the blends were analyzed. Miscibility in PVME/polyester blends were found only in polyesters with backbone CH2/CO ratio = 3.5 to 7.0. Tg-composition relationships for blends of PVME with highly crystalline polyesters (PBA, PHA, PCL, PHS) were found to differ significantly from those for PVME blends with less-crystalline polyesters (PTA, PEAz). Crystallinity of highly-crystalline polyester constituents in blends caused significant asymmetry in the Tg-composition relationships, and induced positive deviation of blends’ Tg above linearity; on the other hand, blends of PVME with less crystalline polyesters exhibit typical Fox or Gordon-Taylor types of relationships. The interaction parameters for the miscible blends were found to range from -0.17 to -0.33, reflecting generally weak interactions. Phase behavior was analyzed and compared among blends of PVME with rapidly-crystallizing vs. less-crystallizing polyesters, respectively. Effects of polyesters’ crystallinity and structures on phase behavior of PVME/polyester blends are discussed. As analogous polyester to PCL, PHA (with the same CH2/CO ratio) was used for comparison purpose; however, PHA has a stronger tendency for crystallization than PCL. Both PVME/PCL and PVME/PHA blends were proven to be miscible with weak and non-specific interactions, which is typical in blends involving ether-containing and carboxyl-containing polymers. Difference in spherulite ring-band patterns between neat PCL, neat PHA and miscible blends was probed to correlate with growth regimes. Spherulite growth in thin-film forms and transformation of spherulite patterns in different regimes were investigated. For neat PCL, in transition from regime III to regime II, the spherulites are patterned in ring-less to ring-banded types, respectively, in different regimes. For the PVME/PCL (20/80) blend, ring bands in spherulites are easily seen in Regime-III, but ring bands disappear in Regime-II. For neat PHA, in transition from regime II to regime I, the spherulites are patterned in ring-banded to ring-less types. For the PVME/PHA (20/80) blend, ring bands in spherulites are easily seen only in crystallization from Tc=40 ~ 42oC (Regime-II), but ring bands disappear in crystallization from Tc=30 ~ 38oC (Regime-II) and Tc=46 ~ 50oC (Regime-I).
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Juang, Yau-Tsung, and 莊曜聰. "Structure Dependence of Miscibility in Blends of Poly(vinyl ether) with Homologous Polyacrylates or Polymethacrylates." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/42890675132530581235.
Full textAbstract:
碩士國立成功大學
化學工程學系碩博士班
93
Effect of the side-chain structure on the miscibility and morphology of poly(vinyl methyl ether)(PVME) and poly(vinyl ethyl ether)(PVEE) with homologous series of polymethacrylates or polyacrylates were investigated by using differential scanning calorimeter (DSC), polarized-optical microscopy (POM), scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR) in this study. In poly(ethyl methacrylate)(PEMA) /poly(vinyl methyl ether)(PVME) blend, solvents strongly affect the morphology and lead to different phase structures of the blends. Although blend system shows a single glass transition temperature, the broadening of the glass transition suggests a marginal miscibility. According to FT-IR the intermolecular interactions are weak and not specific, which is in agreement with the glass transition behavior of the blends. Poly(n-propyl methacrylate)(PnPMA)/PVME and poly(isopropyl methacrylate)(PiPMA) /PVME blend system are immiscible at ambient temperature but actually could become miscible at higher temperatures, exhibiting an interesting and rare UCST phenomenon. If changing the methyl group of the PVME’s side chain into ethyl group, PVEE, the polymetharyltes/PVEE blend are immiscible. In homologous polyacrylates, poly(n-butyl acrylate)(PBA)/PVEE blend system shows homogeneous phase and exhibits a single Tg, indicating a miscible system. Additionally, this study also shows that PVEE is immiscible with any other polyacrylates, such as poly(methyl acrylate)(PMA), poly(ethyl acrylate)(PEA) and poly(n-propyl acrylate)(PPA).
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Lue, Lie-Chuan, and 盧麗娟. "Crown Ether Phase Transfer Catalysts for Anionic Polymerization of Bisphenol A/Sulfone And Vinyl Monomers." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/20522289654487512631.
Full textAbstract:
碩士國立臺灣師範大學
化學學系
82
It's has been demonstrated that crown ethers are able to form quite stable complexes with many metal ions especially alkali metal ions. Crown ethers not only can increase the solubility of metal salts (MX) in organic solvent but also can promate the activation of the anions (X-) of alkali metal salts (MX). IN this study crown ethers were successfully applied as phase-transfer-catalysts for anionic polymerizations of bisphenol A/sulfone and vinyl monomers such as acrylonitrile and styrene. Effects of crown erhers, concentrations of initiators (NaNH2, NaOH, KOH ), solvents, and temperature on polymerization were investrgated, In addition, the moleculat weight, viscosity, IR, and NMR spetra of polymers were studied. Without crown ethers as catalysts, only low yield and low molecular weight polymers were produced, whereas the addition of crown ethers resulted in increase of the yield and molecular weight remarkly. The catalytic abbilities of crown ethers seem to be in the order of : 15 crown 5>B15 crown 5>18C6>DC18C6>DB18C6>12C4. NaNH2 not only can be used as a quite good initiator but also can get rid of the problems of hydrolysis in copolymeriation bisphenol A and 4, 4'-dichloro diphenyl sulfone. The reaction procedures for polymerization of bisphenol A /sulfone, acrylonitrile, and styrene are quite simple and useful, while critical condition were required in the traditional methods for polymerization of bisphenol A/sulfone. Crown ethers have been demonstrated as quite efficient phase-tranrfer-catalysts and maybe to be applied in industrial mass production for these useful polymers in the future.
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YANG, XIAN-WEI, and 楊顯威. "The nuclear magnetic resonance studies of the miscibility of polystyrene/poly (vinyl methyl ether) blend." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/98067088709894671623.
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Davies, Katherine. "An Iterative synthesis of oligo-vinyl ethers and applications thereof." Thesis, 2012. http://hdl.handle.net/1828/3900.
Full textAbstract:
An iterative protocol is a highly efficient strategy for the generation of large, complex molecules that has been applied in many different subfields of organic synthesis. The use of a tandem or cascade reaction is also an effective approach for the rapid introduction of molecular complexity into a system since the number of steps requiring independent optimization is greatly reduced. With the aim of creating new synthetic strategies to efficiently gain access to stereochemically complex small molecules, we envisioned the use of short iterative protocols to prepare reactive oligomers to which a diverse range of cascade cyclization processes could be applied.
In an attempt to minimize reaction optimization and chromatographic purification steps during the development of our small molecule precursors, we first developed an iterative synthesis based on a conjugate addition/reduction sequence that has allowed us to access a diverse series of oligo-vinyl ether intermediates. Significantly, both the addition and reduction steps proceed in near-quantitative yield, and reaction co-products can be removed without column chromatography. At the same time, most of our vinyl ether intermediates are stable to silica gel, and so analytically pure samples can be prepared when desired. Except for when very sterically demanding substrates are employed as electrophiles, the intermediates are isolated as single geometrical isomers. We also developed an improved synthesis of a previously intractable class of alkynoate starting materials (4-aryl-2-butynoates) to ensure a diverse range of easily accessible monomeric building blocks were available for our use.
With this effective iterative route in hand, we have several interesting small molecule targets at our disposal. We first applied our iterative route to synthesize oxygen-containing analogues of juvenile hormone III. These mono- and bis-vinyl ethers are currently undergoing biological testing (in collaboration with Dr. Steve Perlman and Dr. Michael Horst), and early results show promise as ecologically degradable insect control agents.
We also developed an unprecedented 6-endo/5-exo radical cascade reaction across bis-vinyl ethers which proceeds in good yield, high diastereoselectivity, and excellent regiochemical control. This reaction represents the first cascading radical cyclization ever reported for a bis-vinyl ether system and validates our iterative approach to molecular complexity.Graduate
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Jiang, Z., Y. Wang, L. Fu, Benjamin R. Whiteside, John Wyborn, Keith Norris, Z. Wu, Philip D. Coates, and Y. Men. "Tensile Deformation of Oriented Poly(ε-caprolactone) and Its Miscible Blends with Poly(vinyl methyl ether)." 2013. http://hdl.handle.net/10454/6037.
Full textAbstract:
The structural evolution of micromolded poly(ε-caprolactone)
(PCL) and its miscible blends with noncrystallizable poly(vinyl
methyl ether) (PVME) at the nanoscale was investigated as a function of
deformation ratio and blend composition using in situ synchrotron smallangle
X-ray scattering (SAXS) and scanning SAXS techniques. It was
found that the deformation mechanism of the oriented samples shows a
general scheme for the process of tensile deformation: crystal block slips
within the lamellae occur at small deformations followed by a stressinduced
fragmentation and recrystallization process along the drawing
direction at a critical strain where the average thickness of the crystalline
lamellae remains essentially constant during stretching. The value of the
critical strain depends on the amount of the amorphous component
incorporated in the blends, which could be traced back to the lower
modulus of the entangled amorphous phase and, therefore, the reduced network stress acting on the crystallites upon addition of
PVME. When stretching beyond the critical strain the slippage of the fibrils (stacks of newly formed lamellae) past each other
takes place resulting in a relaxation of stretched interlamellar amorphous chains. Because of deformation-induced introduction of
the amorphous PVME into the interfibrillar regions in the highly oriented blends, the interactions between fibrils becomes
stronger upon further deformation and thus impeding sliding of the fibrils to some extent leading finally to less contraction of the
interlamellar amorphous layers compared to the pure PCLNational Natural Science Foundation of China (21204088 and 21134006). This work is within the framework of the RCUK/EPSRC Science Bridges China project of UK−China Advanced Materials Research Institute (AMRI).
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Al-Dossary, Mona S. "Synthesis and Properties of the Metallo-Supramolecular Polymer Hydrogel Poly[methyl vinyl ether-alt-mono-sodium maleate]∙AgNO3." Thesis, 2014. http://hdl.handle.net/10754/316937.
Full textAbstract:
Gels are a special class of materials which are composed of 3D networks of crosslinked polymer chains that encapsulate liquid/air in the matrix. They can be classified into organogels or hydrogels (organic solvent for organogel and water for hydrogel). For hydrogels that contain metallic elements in the form of ions, the term of metallo-supramolecular polymer hydrogel (MSPHG) is often used. The aim of this project is to develop a kind of new MSPHG and investigate its properties and possible applications. The commercial polymeric anhydride poly(methyl vinyl ether-alt-maleic anhydride) (PVM/MA) is converted by reaction with NaOH to give poly(methyl vinyl ether-alt-monosodium maleate) (PVM/Na-MA). By addition of AgNO3-solution, the formation of the silver(I) supramolecular polymer hydrogel poly[methyl vinyl ether-alt-mono-sodium maleate]∙AgNO3 is obtained. Freeze-dried samples of the hydrogel show a mesoporous network of polycarboxylate ligands that are crosslinked by silver(I) cations. The supercritical CO2 dried silver(I) hydrogel was characterized by FT-IR, SEM-EDAX, TEM, TGA and Physical adsorption (BET) measurements. The intact silver(I) hydrogel was characterized by cryo-SEM. In the intact hydrogel, ion-exchange studies are reported and it is shown that Ag+ ions can be exchanged by copper(II) cations without disintegration of the hydrogel. The silver(I) hydrogel shows effective antibacterial activity and potential application as burn wound dressing.
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Quinn, Michael Patrick. "Boron and Titanium(IV) Halide Mediated Reactions." 2010. http://trace.tennessee.edu/utk_graddiss/908.
Full textAbstract:
This dissertation summarizes research efforts focused on the use of boron and transition metal halides to form new carbon-carbon and carbon-halide bonds. The boron halide mediated alkyne-aldehyde coupling reaction to generate 1,3,5-triaryl-1,5-dihalo-1,4-dienes was reinvestigated in an attempt to explain the stereochemistry observed during changing of both the mode of addition and the reaction temperature. Either (Z,Z)-1,4-dienes or (Z,E)-1,4-dienes can be the predominant product depending on reaction conditions used. This mechanistic investigation also led to the discovery of several novel reactions. These include the stereoselective preparation of (Z)-3-chloroallylic ethers from the reaction of alkenylboron dichlorides with aryl aldehydes in the presence of an amine; the titanium(IV) halide coupling of alkoxides and alkynes; the haloallylation of aryl aldehydes with boron trihalide using different allylmetals; and the base induced elimination of the haloallylated products to form 1,3-dienes. The results of these studies strongly imply a cationic mechanism. The new reactions described herein can be characterized as atom-efficient, environmentally friendly, and capable of generating the desired products in good to excellent yields.
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MAO, Yung-jen, and 毛勇仁. "Phase Behavior and Miscibility in a Ternary Blend System Comprising Polycaprolactone, Poly(benzyl methacrylate) and Poly(vinyl methyl ether)." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/15644801075846606593.
Full textAbstract:
碩士國立成功大學
化學工程學系
88
Phase behavior and miscibility of a ternary polymer blend comprising polycaprolactone (PCL), poly(benzyl methacrylate) (PBzMA) and poly(vinyl methyl ether) (PVME) was investigated by polarizing optical microscopy (POM), scanning electron microscopy (SEM), differential scanning calorimeter (DSC) and Fourier-transform infrared spectroscopy (FTIR). Each composition of the ternary mixture forms a miscible blend with a homogeneous phase structure. The ternary blend system exhibits lower critical solution temperature (LCST) behavior through optical observation for phase separation on heating. The existence of a single Tg in each blend also indicates that the ternary blend system is miscible according to the conventional standard of glass transition. Nevertheless, widening of the thermal transition breadth was obvious and contingent upon blend composition suggesting that miscellaneous scales of molecular aggregation. The FTIR result shows that the intermolecular interactions were weak and not specific