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1
Gallet, Yves. "La magnetostratigraphie : aspects fondamentaux et appliques." Paris 7, 1988. http://www.theses.fr/1988PA077056.
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Une eetude magnetostratigraphique de la limite jurassique/cretace au maroc permet de discuter les possibilites de correlation stratigraphique en l'absence d'une biostratigraphie bien etablie. Avec des donnees du forage de cony, on met en evidence des series triasiques et permiennes. Les resultats paleomagnetiques permettent de preciser la derive des poles magnetiques de l'eurasie. On modelise aussi le champ magnetique a l'interieur d'un forage
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CAMMAS, SANDRINE. "Le poly (acide beta-malique) et ses derives : synthese et caracterisation." Paris 6, 1993. http://www.theses.fr/1993PA066328.
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L'interet recent pour le devenir des polymeres dans l'environnement fait de la biodegradation une propriete necessaire pour certaines utilisations, mais sa realisation n'est pas evidente. Cependant, l'interet pour de telles structures macromoleculaires, destinees a disparaitre apres une utilisation temporaire, est reconnu depuis plus de dix ans en chirurgie et en pharmacologie. Dans le domaine pharmaceutique, la synthese de nouvelles formes galeniques necessite le developpement de nouveaux polymeres possedant des specifications tres strictes. C'est pourquoi, m. Vert et r. W. Lenz ont choisi le poly (acide beta-malique), polymere correspondant aux specifications des materiaux bioresorbables pour des utilisations therapeutiques temporaires. Le poly (acide beta-malique) est le parent d'une large famille de derives grace a la presence de la fonction acide carboxylique laterale. Plus particulierement, l'introduction de fonctions esters laterales est tres interessante pour modifier la balance hydrophobe/hydrophile des derives et ainsi modifier et ajuster les proprietes telles que la solubilite et la degradation en fonction du nombre et de la repartition de ces groupes dans la chaine. Les proprietes physico-chimiques du materiau peuvent etre egalement modulees en jouant sur la composition enantiomerique du carbone asymetrique de la chaine principale et par l'introduction d'un second centre de chiralite dans la chaine laterale ou principale. Ce memoire presente la synthese et la caracterisation (masses, structure) du poly (acide beta-malique) et de ses derives ainsi que l'etude d'un poly (acide malique) naturel mis en evidence dans un microorganisme
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Dolman, Richard. "Physical properties derived from seismic modelling at the toe of the Barbados accretionary complex." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364522.
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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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Pena, Paula Cristina de Aguiar. "Semi-pinacol rearrangements of epoxy tertiary alcohols derived using poly-L-leucine methodology." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272797.
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Renard, Isabelle. "Derives du poly(acide beta-malique) : modulation des proprietes par modification de leurs structures." Paris 6, 1995. http://www.theses.fr/1995PA066447.
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Quel que soit le domaine d'utilisation des polymeres, l'ajustement necessaire des proprietes du materiau a une application choisie implique l'elargissement du spectre des polymeres disponibles. Les polymeres biodegradables ont un interet tout particulier pour un secteur industriel important: le biomedical. Les normes pour ce domaine sont strictement controlees et le cahier des charges est bien precis pour chaque application. Dans la partie bibliographique de ce memoire, nous abordons le probleme des prodrogues macromoleculaires: leur place dans la liberation controlee des molecules therapeutiquement actives, les types de polymeres utilises, la presence d'un groupement espaceur pour faciliter le relargage de la drogue, les possibilites de ciblage pour augmenter l'efficacite du medicament. Le travail de recherche est divise en deux parties. La premiere presente la synthese des derives du poly(acide beta-malique) possedant des unites malates d'alkyle dont le groupement alkyle est peu encombrant. Ces polymeres passent par la synthese de beta-lactones beta-substituees. L'acces a ces monomeres varie en fonction du substituant et necessite la mise au point de voies de syntheses particulieres. Divers mecanismes sont proposes afin d'expliquer les reactions qui peuvent intervenir et empecher dans certains cas l'acces aux monomeres. L'obtention d'homo ou de copolymeres de hautes masses molaires possedant des groupements peu encombrants varie egalement en fonction de l'encombrement du groupement alkyle, ce qui fait intervenir des reactions de transfert. Neanmoins, les polymeres de masses molaires faibles ou moyennes sont utilises en tant que modele pour la synthese de prodrogues macromoleculaires. La derniere partie est consacree a la synthese et a l'etude du poly(acide beta-3-methylmalique). Ce nouveau polyester de type poly(beta-hydroxy acide) elargit la famille des derives du poly(acide beta-malique) en permettant le faconnage de polystereoisomeres possedant simultanement, sur la chaine macromoleculaire, deux centres stereogenes, des groupements alkyles hydrophobes et des fonctions acides carboxyliques hydrophiles
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Rebourt, Eymard. "Vers des polymères conducteurs tridimensionnels : préparation et caractérisation de poly(n-octyl-3-thiophènes) réticulés totalement conjugués." Université Joseph Fourier (Grenoble), 1994. http://www.theses.fr/1994GRE10182.
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Il nous a paru interessant de jouer sur la dimensionnalite des polymeres conducteurs electroniques afin d'obtenir des materiaux dont les proprietes (notamment la conductivite) seraient particulieres. D'ou l'idee de preparer des structures totalement conjuguees de dimension fractale voire tridimensionnelles. Pour obtenir ces structures, nous avons reticule des chaines de poly(n-octyl-3-thiophene) avec quatre types de trithienylbenzenes prealablement prepares et caracterises: le tri(thienyl-2)-1,3,5-benzene, le tri(thienyl-2)-1,2,4-benzene, le tri(thienyl-3)-1,3,5-benzene et le tri(thienyl-3)-1,2,4-benzene. La reactivite des quatre types de points de reticulation a ete etudiee. Pour cela, des copolymeres ont ete prepares avec les quatre differents points de reticulation deuteries sur les positions supposees reactives. L'etude par spectroscopie ir des copolymeres ainsi obtenus a permis de determiner des pourcentages de positions supposees reactives des points de reticulation ayant effectivement reagi pendant la copolymerisation. 22 copolymeres ont ete prepares en faisant varier la teneur r en point de reticulation dans le melange reactionnel. Lorsque seule une fraction soluble est obtenue, la caracterisation du copolymere est tres delicate. En revanche, lorsque nous obtenons une fraction soluble et une fraction insoluble, en faisant l'hypothese que tous les points de reticulation sont presents uniquement dans la fraction insoluble, nous pouvons determiner des valeurs limites superieures de r dans les fractions insolubles. Ces copolymeres insolubles presentent des conductivites en continu semblables a celle du poly(n-octyl-3-thiopene). Ce sont des gels dont le taux de gonflement varie lineairement en fonction de l'inverse de r, ce qui est l'indice que la repartition des points de reticulation dans les copolymeres est homogene. Les fractions insolubles ont ete caracterisees par differentes methodes: ir, dsc, diffraction des rayons x, rpe
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BOUTAULT-CHENON, KARINE. "Synthese et caracterisation de derives du poly(acide b-malique) presentant deux centres de chiralite." Nantes, 1995. http://www.theses.fr/1995NANT2081.
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L'utilisation des ressources renouvelables du gisement naturel que constitue la biomasse peut etre un moyen d'acces a de nouvelles molecules monomeres et donc a de nouveaux materiaux polymeres. Nous avons choisi de partir de l'acide threo (2s,3s)-3-isopropylaspartique obtenu par bioconversion sous l'action de la b-methylaspartase, pour preparer la lactone monomere (3s,4r)-3-isopropyl-4-benzyloxycarbonyl-2-oxetanone qui est ensuite polymerisee anioniquement par ouverture de cycle en poly(threo-(2s,3s)-b-3-isopropylmalate de benzyle). Ce polymere est ensuite deprotege par hydrogenolyse catalytique, specifique du groupement benzyle, pour conduire au poly(threo(2s,3s)-acide-b-3-isopropylmalique). L'interet de ces nouveaux polyesters degradables optiquement actifs est evident: non seulement ils peuvent etre hydrolyses avec des vitesses de degradation variables grace a la presence des deux centres asymetriques, mais la fonction acide laterale peut conduire a des multimeres fonctionnalises. Nous avons elargi la gamme des polymeres derives de l'acide malique en synthetisant des poly(b-malate d'alkyles) presentant deux centres de chiralite. Les differents polystereoisomeres du poly(b-malate de 2-butyle) et du poly(b-malate de 3,3-dimethyl-2-butyle) ont ete prepares et caracterises
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ALGARRA, LIONEL. "Amines grasses (poly)glycerylees et derives : syntheses, caracterisations fondamentales, et evaluation de leur potentiel industriel." Rennes 1, 1999. http://www.theses.fr/1999REN10131.
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Les tensioactifs glyceryles constituent une classe d'amphiphiles non ioniques appelee a remplacer les derives ethoxyles dans le cadre d'une eventuelle modification de la legislation en matiere de toxicite et de biodegradabilite. Les ethers et esters de glycerol etant largement decrits, nous nous sommes orientes vers l'etude d'amines grasses glycerylees. La premiere partie de ce memoire presente les syntheses d'amphiphiles mono- et bicatenaires. La strategie employee utilise des synthons polyglycerol et permet d'acceder a des amines polyglycerylees definies, et non a des melanges ayant une distribution statistique du nombre de motifs glycerol. Pour developper l'interet industriel de ces composes, l'optimisation des voies de syntheses et la preparation de nouveaux derives bicatenaires sont decrites. Les amines glycerylees interviennent alors comme intermediaires pour l'obtention de catanioniques et de pseudoceramides. La caracterisation des systemes moleculaires organises formes par les amphiphiles glyceryles necessite des methodes d'analyses physico-chimiques dont les principes sont rappeles dans la deuxieme partie. Les resultats de ces etudes sont presentes dans la derniere partie pour les trois familles. Les amines grasses monocatenaires possedent un bon pouvoir tensioactif, et des proprietes cristallines liquides qui peuvent etre exploitees pour la synthese de solides mesoporeux. De plus leur comportement en formulation peut etre module par plusieurs parametres. Les catanioniques glyceryles sont des cristaux liquides amphotropes, qui conduisent a la formation de nombreux types de phases lamellaires et de liposomes. Les amphiphiles glyceryles etudies presentent des caracteristiques interessantes pour des applications en detergence, en cosmetique ou en pharmacie. Leurs bonnes proprietes tensioactives et cristallines liquides en font des concurrents des composes ethoxyles, en particulier dans les domaines ou leur caractere biodegradable represente un atout supplementaire.
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Lavoie, Jean-Michel. "Mammalian cell culture on poly (dimethyl siloxane) functionalized for covalent immobilization of extracellular matrix-derived proteins." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116017.
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In vitro cell culture is an essential part of many cell and tissue engineering approaches. In particular, monolayer culture of mammalian cells is a key tool for applications such as cell therapy. Novel bioreactors like the Cellerator(TM) allow for expansion of cell populations on mechanically stimulated surfaces coated with proteins. This thesis constitutes a preliminary study which focused on cell-matrix interactions in the absence of stretch. The aim was to establish standard protocols for protein coating on poly (dimethyl siloxane) (PDMS) and for measuring cell proliferation. Specifically, the proliferation of rat pulmonary artery vascular smooth muscle (PAC1) cells on type I collagen and soluble fibronectin was studied. Growth curves were obtained and the doubling time for subconfluent cultures was computed. Although cell-matrix interactions do not enhance proliferation of PAC1 cells, it was found that a preliminary sulphuric acid treatment is necessary to yield a well-behaved culture.
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Machado, Thiago Ouriques. "Synthesis of Poly(thioether-ester) nanoparticles derived from renewable resources via thiol-ene polymerization in miniemulsion." reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/160646.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2015.Made available in DSpace on 2016-04-19T04:05:04Z (GMT). No. of bitstreams: 1 337587.pdf: 1909336 bytes, checksum: d0d665576c317d2582474610cce5d6a9 (MD5) Previous issue date: 2015
Abstract : Green chemistry has drawn attention from researchers and even some industries due to concerns about the depletion of fossil oil reserves and aggravation in the global warming and other environmental issues. Polymeric materials from biofeedstocks-derived monomers are a promising environmentally friendly alternative to petrol-derived polymers, especially for high value added applications. In this context, vegetable oils and saccharides are interesting raw materials that can be applied as chemical platforms in the synthesis of novel fully renewable monomers through chemical modification. In addition, thiol-ene polymerization has been shown as a versatile tool to produce polymers from fully renewable a,?-diene monomers bearing, for example ester, ether, or amide functional groups in the backbone chain. However, works portraying the polymerization of renewable monomers through thiol-ene polymerization in dispersed medium are still uncommon. Herein, it is presented the synthesis and characterisation of poly(thioether-ester) nanoparticles via thiol-ene polymerization in miniemulsion using a monomer derived from renewable resources. The synthesis of a renewable a,?-diene diester monomer, dianhydro-D-glucityl diundec-10-enoate (DGU), produced from 10-undecenoic acid (derived from castor oil) and isosorbide (derived from starch) was performed. DGU was copolymerized with 1,4-butanedithiol (Bu(SH)2) through thiol-ene polymerization both in bulk and miniemulsion to yield linear semi-crystalline poly(thioether-ester)s. Different parameters were evaluated such as reaction temperature, initiator concentration, surfactant type and surfactant concentration. Particle size distribution and morphology was observed by DLS and TEM respectively resulting in spherical particles with an intensity average particle diameter around 200 nm. Polymer with higher molecular weight was obtained by miniemulsion polymerization when compared to bulk polymerization. Number average molecular weight of 11 kDa was obtained through miniemulsion polymerization at 80°C for 4h using AIBN at 1 mol% (in relation to Bu(SH)2). Furthermore, DSC and XRD analyses have shown that the synthesized polymer was semi-crystalline with a degree of crystallinity above 20% and Tm around 60°C. Finally, depending on the co-stabilizer type, hexadecane or Crodamol, and amount, phase segregation within polymer particles was observed through DSC.
A química verde tem chamado a atenção de pesquisadores e até mesmo de algumas indústrias devido à preocupação com o esgotamento das reservas fósseis e o agravamento de problemas ambientais. Materiais poliméricos obtidos de monômeros derivados de fontes renováveis são uma alternativa ambientalmente correta aos polímeros derivados do petróleo, especialmente para aplicações de alto valor agregado. Neste contexto, óleos vegetais e sacarídeos são matérias-primas interessantes que podem ser utilizadas como plataformas químicas para a síntese de novos monômeros, completamente renováveis, através da modificação química. Além disso, polimerização tiol-eno mostrou-se uma versátil ferramenta para a produção de polímeros a partir de monômeros verdes (a,?-dienos) providos de grupos funcionais como éster, éter ou amida na cadeia principal. Entretanto, trabalhos sobre a polimerização de monômeros renováveis através da polimerização tiol-eno em meios dispersos ainda são escassos. Neste trabalho, a síntese e a caracterização de nanopartículas de poli(tioéter-éster) via polimerização tiol-eno em miniemulsão usando um monômero proveniente de fontes renováveis são apresentadas. O monômero verde utilizado é um a,?-dieno diéster, diundec-10-enoato de dianidro-D-glucitila (DGU), produzido a partir de ácido 10-undecenóico (derivado do óleo de mamona) e isosorbídeo (derivado do amido). DGU foi copolimerizado com 1,4-butanoditiol (Bu(SH)2) através polimerização tiol-eno em massa e em miniemulsão para produzir poli(tioéter-éster) linear e semicristalino. Diferentes parâmetros foram avaliados, como por exemplo temperatura, concentração de iniciador, tipo e concentração do surfactante. A distribuição de tamanho e a morfologia das partículas foram observadas por DLS e TEM respectivamente, revelando partículas esféricas com diâmetro de 200 nm. O polímero obtido pela polimerização em miniemulsão, 11 kDa onde as condições reacionais foram 80°C por 4h usando 1 mol% de AIBN (em relação ao Bu(SH)2), mostrou-se com maior massa molar em comparação àquele obtido em polimerização em massa. Análises de DSC e DRX mostraram que o polímero sintetizado é semicristalino com grau de cristalinidade de pelo menos 20% e Tm em torno de 60°C. Dependendo do tipo de co-estabilizador utilizado, hexadecano ou Crodamol, e da quantidade, pode-se observar por DSC segregação de fases nas partículas poliméricas.
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Kim, Yoon-Sung. "Synthese, caracterisation et structure de poly beta-amides aspartiques portant des groupes lateraux derives du carbazole." Paris 6, 1988. http://www.theses.fr/1988PA066331.
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Polymerisation non-assistee des esters benzylique, carbazolyl-9 ethyliques-2 et du (carbazolyl-9) ethylamide-2 de l'acide oxo-4 azetidinecarboxylique-2 et etude par ir de leur structure et notamment des liaisons imide inter- et intramoleculaire
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Beyer, Doreen, Shiyong Wang, Carlo A. Pignedoli, Jason Melidonie, Bingkai Yuan, Can Li, Jan Wilhelm, et al. "Graphene Nanoribbons Derived from Zigzag Edge-Encased Poly(para-2,9-dibenzo[bc,kl]coronenylene) Polymer Chains." ACS Publications, 2019. https://tud.qucosa.de/id/qucosa%3A37010.
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In this work, we demonstrate the bottom-up on-surface synthesis of poly(para-dibenzo[bc,kl]-coronenylene) (PPDBC), a zigzag edge-encased analog of poly(para-phenylene) (PPP), and its lateral fusion into zigzag edge-extended graphene nanoribbons (zeeGNRs). Toward this end, we designed a dihalogenated di(meta-xylyl)anthracene monomer displaying strategic methyl groups at the substituted phenyl ring and investigated its applicability as precursor in the thermally induced surface-assisted polymerization and cyclodehydrogenation. The structure of the resulting zigzag edge-rich (70%) polymer PPDBC was unambiguously confirmed by scanning tunneling microscopy (STM) and non-contact atomic force microscopy (nc-AFM). Remarkably, by further thermal treatment at 450 °C two and three aligned PPDBC chains can be laterally fused into expanded zeeGNRs, with a ribbon width of nine (N = 9) up to 17 (N = 17) carbon atoms. Moreover, the resulting zeeGNRs exhibit a high ratio of zigzag (67%) vs armchair (25%) edge segments and feature electronic band gaps as low as 0.9 eV according to gaps quasiparticle calculations.
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Xia, Changlei. "Biomass-Derived Activated Carbon Through Self-Activation Process." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849716/.
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Self-activation is a process that takes advantage of the gases emitted from the pyrolysis process of biomass to activate the converted carbon. The pyrolytic gases from the biomass contain CO2 and H2O, which can be used as activating agents. As two common methods, both of physical activation using CO2 and chemical activation using ZnCl2 introduce additional gas (CO2) or chemical (ZnCl2), in which the CO2 emission from the activation process or the zinc compound removal by acid from the follow-up process will cause environmental concerns. In comparison with these conventional activation processes, the self-activation process could avoid the cost of activating agents and is more environmentally friendly, since the exhaust gases (CO and H2) can be used as fuel or feedstock for the further synthesis in methanol production. In this research, many types of biomass were successfully converted into activated carbon through the self-activation process. An activation model was developed to describe the changes of specific surface area and pore volume during the activation. The relationships between the activating temperature, dwelling time, yield, specific surface area, and specific pore volume were detailed investigated. The highest specific surface area and pore volume of the biomass-derived activated carbon through the self-activation process were up to 2738 m2 g-1 and 2.209 cm3 g-1, respectively. Moreover, the applications of the activated carbons from the self-activation process have been studied, including lithium-ion battery (LIB) manufacturing, water cleaning, oil absorption, and electromagnetic interference (EMI) shielding.
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Aguiar, Kelen Menezes Flores Rossi de. "Síntese de hidroxiuretana-poli(dimetilsiloxano) com diferentes terminações de cadeia via fixação de CO2: síntese, caracterizações e potenciais aplicações." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-26102015-114419/.
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Neste trabalho uretanas livres de isocianatos produzidas a partir de um precursor bis(ciclocarbonato) oligomérico contendo segmentos de poli(dimetil siloxano) (CCPDMS) foram sintetizadas. Para tal, utilizou-se diferentes aminas primárias como a 3-aminometil-3,5,5 trimetilciclohexilamina (IPDA) e as monoaminas 3-aminopropil(trietóxisilano) (APTES), feniletilamina (PEA), catecol amina (dopamina) e um decapeptídeo derivado da proteína de adesão de mariscos (mefp-1).O precursor oligomérico CCPDMS foi produzido por fixação de dióxido de carbono em anéis epóxi catalisado por um sal quarternário de amônio, o brometo de tetraetilamônio (BTA). O precursor CCPDMS foi então reagido com as aminas por meio de polimerização por abertura de anel formando hidroxiuretanas derivadas de PDMS (PDMSUr) com diferentes terminações de cadeia. Tendo como terminador de cadeia o APTES, foi possível produzir um material híbrido com domínios inorgânicos de sílica organicamente modificada (ormosil) interligadas com a parte orgânica de PDMS por meio de ligações uretana. Nesta matriz híbrida foram adicionadas diferentes porcentagens mássicas de ácido fosfotúngstico (PWA), variando entre 1% a 55%. Os materiais foram caracterizados quanto à sua estrutura química por técnicas espectroscópicas (Ressonância Magnética Nuclear, Infravermelho, Espectroscopia de Fotoelétrons, MALDI-ToF), propriedade anti-corrosão (espectroscopia de impedância eletroquímica, polarização potenciodinâmica), propriedades superficiais (energia livre superficial, nanoindentação), análise morfológica (Microscopia Eletrônica de Varredura), estabilidade térmica (Análise Termogravimétrica), testes de adesão (pull-off-test e cisalhamento), testes microbiológicos (adesão de bactérias, tecidos e citotoxicidade), além de ensaios de fotocromismo. O polioxometalato PWA conferiu propriedades fotocrômicas aos filmes híbridos de PDMSUr com máxima absorbância de 1,6 u.a após irradiação por luz ultra-violeta (UV). PDMSUr híbridas com ou sem PWA foram testadas como adesivos para vidro, alumínio, aço (SS316L) e liga de titânio (Ti6Al4V) apresentando valores de força de adesão entre 2-7 MPa. Filmes de PDMSUr preparados em diferentes substratos apresentaram comportamento bacteriostático frente à adesão de Escherichia coli (E.coli) e Lactobacillus casei (L.casei). A PDMSUr biomimética terminada por grupos catecóis foi capaz de formar camadas em superfícies metálicas apresentando boa estabilidade frente à remoção da camada depositada por lavagem com etanol.Free isocyanate urethanes produced from an oligomeric precursor bis(cyclic carbonate) bearing poly(dimethylsiloxane) (CCPDMS) were synthesized in this work. Different primary amines such as 3-Aminomethyl-3,5,5-trimethylcyclohexylamine (IPDA) and monoamines 3-aminopropyltriethoxysilane (APTES), phenylethylamine (PEA), catechol amine (dopamine) and a decapeptide derived from marine mussel foot protein (mefp-1). The precursor cyclic carbonate CCPDMS was obtained from carbon dioxide fixation into epoxy rings catalized by a quaternary ammonium salt, tetraethylamonium bromide (TEAB). The precursor CCPDMS was reacted with the different amines by ring opening polymerization affording the formation of hydroxyurethanes PDMS derived (PDMSUr) with different chain terminations. Using APTES as chain terminator was feasible to obtain a hybrid material containing inorganic domains of organically modified silica (ormosil) interconnected to the organic part PDMS through urethane bond. In this hybrid matrix different mass percentages, varying from 1%wt to 55 wt%, of phosphotungstic acid (PWA) were added. The materials were characterized regarding their chemical structure by spectroscopic techniques (Nuclear Magnetic Resonance, Infrared, and X-ray photoelectron spectroscopy), mass spectrometry (MALDI-ToF and GPC), anti corrosive property (Electrochemical Impedance Spectroscopy and potentiodynamic polarization), surface properties (free surface energy, nanoindentation), morphology (Scanning Electron Microscopy), thermal stability (Thermogravimetric analysis), adhesion strenght measurements (pull-off-test and lap-shear), microbiologic assays (bacteria adhesion, tissue adhesion and citotoxicity test) besides photochromic assays. The polyoxometalate PWA provided photochromic property to the PDMSUr hybrid films presenting a maximum absorbance of 1.6 a.u after ultraviolet (UV) irradiation. Hybrids PDMSUr with or without PWA were tested as adhesive for glass, aluminium, steel (SS316L) and titanium alloy (Ti6Al4V) showing adhesion strength values ranging from 2-7 MPa. PDMSUr films prepared on different substrates showed bacteriostatic behavior against Escherichia coli (E.coli) and Lactobacillus casei (L.casei). The biomimetic PDMSUr catechol endcapped was able to form a layer on metallic surfaces showing good stability after rinsing with ethanol.
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BALAEI, SALEH. "Nouvelles methodes spectrofluoroelectrochimiques appliquees a l'etude des films de poly(n-vinylcarbazone) et d'autres derives du carbazole." Paris 7, 1991. http://www.theses.fr/1991PA077213.
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Deux nouvelles methodes spectrofluoroelectrochimiques ex situ et in situ ont ete developpees et appliquees a l'etude des processus electrochimiques d'oxydoreduction des films de pvca (poly(n-vinylcarbazole) prepares dans une solution n(bu)4c104; n(bu)4pf6 et n(bu)4bf4 (0,1m) d'acetonitrile. La methode ex situ indique l'existence de differences importantes entre structure des films de pvca chimiques et electropolymerises et permet de distinguer entre les films du pvca dopes et non dopes. La methode in situ (sfeis) permet d'evaluer le degre de reversibilite du systeme pvca/pvca+, qui varie selon la sequence c104>pf6>bf4. Les principales caracteristiques du processus redox et de l'oligomerisation electrochimiques du n-ethylcarbazone, de son dimere, du n-vinylcarbazole (nvc) et du carbazole non substitue sont etudiees fluorimetriquement en solution d'acetonitrile. Les resultats sont confirmes par analyse clhp
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MORONI, MARC. "Polymeres rigides solubles pour l'optique non-lineaire : synthese et caracterisation de derives substitues du poly(p-phenyleneethynylene)." Université Louis Pasteur (Strasbourg) (1971-2008), 1995. http://www.theses.fr/1995STR13050.
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Dans le but d'obtenir de nouveaux materiaux organiques pour l'optique non lineaire, une serie de poly(para-phenyleneethynylenes) a ete preparee par polycondensation, catalysee par un complexe du palladium. Le greffage de longues chaines alkyles souples a permis d'accroitre la solubilite des materiaux et d'obtenir des polymeres de grande masse. La nature chimique des substituants influe sur la conjugaison, qui a ete etudiee par spectroscopie uv-visible et diffusion raman. Des oligomeres de taille determinee, modeles des polymeres precedents, ont ete prepares. Une etude de la longueur de delocalisation electronique a ainsi ete effectuee. Des copolymeres alternes ont ete synthetises. La conjugaison est accrue en incorporant dans le squelette rigide des groupements aromatiques particuliers, comme l'anthracenyle, ou des cycles aromatiques qui provoquent de forts transferts de charge intramoleculaires. La formation de liaisons hydrogene intramoleculaires ameliore la planeite de la chaine et le recouvrement orbitalaire, ce qui accroit la conjugaison. De tres fortes susceptibilites d'ordre trois ont ete observees par melange d'ondes degenerees et par triplement de frequence sur plusieurs polymeres et copolymeres
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TORCQ, FREDERIC. "Evolution et destruction de la pangee du carbonifere au jurassique derive des poles magnetiques et etude de la dipolarite du champ." Paris 7, 1997. http://www.theses.fr/1997PA077082.
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L'analyse des donnees d'arabie nous a permis de definir un pole paleomagnetique pour le gondwana ouest a 244 millions d'annees. Nos donnees sont en faveur d'une pangee evolutive (pangee de type b) ou la partie nord de l'amerique du sud fait face a l'est de l'amerique du nord pour les epoques allant du permien au trias inferieur. L'analyse des donnees argentines confirme nos conclusions obtenues pour l'arabie a la limite entre le permien et le trias et nous permet de calculer un pole pour le gondwana a la limite permo-carbonifere lui-meme en faveur d'une pangee de type b. Nos donnees impliquent donc une configuration des plaques differente de wegener et un decrochement de 3500 kilometres entre gondwana et laurussie du permien superieur au trias superieur. Deux missions effectuees en 1994 et 1995 dans la region d'abadeh (iran) nous ont permis de deduire l'evolution en latitude du bloc iranien entre le permien superieur et le trias superieur. Celui-ci migre entre le gondwana et la laurussie a une vitesse de l'ordre de 13 centimetres par an. De maniere a tester l'hypothese du dipole axial centre qui permet de comparer entre eux des poles paleomagnetiques lorsque aucune cinematique oceanique n'est disponible, nous avons constitue une base de donnees mondiale entre 0 et 140 millions d'annees en utilisant en plus des donnees a terre les donnees de sites dsdp, et des paleopoles calcules a partir des anomalies magnetiques marines (skew). L'observation de la distribution statistique des donnees pour chacun de ces poles confirme l'hypothese du dipole axial.
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Schreiber, Martin Schreiber Martin. "Synthese und Charakterisierung funktionalisierter Tetraethinylethen-, Oligo(pentaacetylen)- und Poly(triacetylen)-Derivate sowie expandierter Radialene /." [S.l.] : [s.n.], 1996. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11904.
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Oschatz, M., W. Nickel, M. Thommes, K. A. Cychosz, M. Leistner, M. Adam, G. Mondin, P. Strubel, L. Borchardt, and S. Kaskel. "Evolution of porosity in carbide-derived carbon aerogels." Royal Society of Chemistry, 2014. https://tud.qucosa.de/id/qucosa%3A36239.
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Carbide-derived carbon (CDC) aerogel monoliths with very high porosity are synthesized starting from polymeric precursors. Cross-linking by platinum-catalyzed hydrosilylation of polycarbosilanes followed by supercritical drying yields preceramic aerogels. After ceramic conversion and silicon extraction in hot chlorine gas, hierarchically porous carbon materials with specific surface areas as high as 2122 m² g⁻¹ and outstanding total pore volumes close to 9 cm³ g⁻¹ are obtained. Their pore structure is controllable by the applied synthesis temperature as shown by combined nitrogen (-196 °C) and carbon dioxide (0 °C) measurements coupled with electron microscopic methods. The combination of large micropore volumes and the aerogel-type pore system leads to advanced adsorption properties due to a combination of large storage capacities and effective materials transport in comparison with purely microporous reference materials as shown by thermal response measurements.
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Gervasio, Michelle Rose. "Sub-micron Patterning of ZnO-PMMA Hybrid Films." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/86887.
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Sub-micron patterning is fundamental to the fabrication of numerous devices Traditional commercial manufacturing methods either lack the resolution needed to attain the appropriate size or are prohibitively expensive due to low throughput or the necessity of expensive equipment. Imprint lithography is a rapid, inexpensive alternative to making sub-micron features that can be tailored to work with a variety of materials. Imprint lithography, while traditionally used with pure polymers has been tailored to be used with nanoparticle-polymer hybrid films. This work has achieved high-fidelity pattern transfer onto polymer-nanoparticle hybrid films with feature sizes as small as 250 nm.
The polymer-nanoparticle hybrid was fabricated by creating a liquid suspension of functionalized ZnO nanoparticles and poly(methyl methacrylate) (PMMA) in a solvent. The ZnO particles were functionalized by adding nonanoic acid in order to facilitate the dispersion of the particles in a non-polar solvent. This suspension was spread onto substrate, imprinted with a patterned stamp, allowed to dry, and was demolded. The final result was features ranging from 250 nm to 1 μm in size with good fidelity as determined by the accuracy of the feature replication and the surface roughness of the overall sample. The effect of the ZnO content as well as the method of combining the suspension components on the feature fidelity was studied. In general, it was found that feature fidelity is acceptable up to a dry-film composition of 15 vol% ZnO and that feature sizes above 500 nm were more tolerant of higher solids loading.
The same imprint lithography method was also used to pattern a polymer-derived SiOC glass. The SiOC was shown to be have interesting shrinkage properties where the feature-level linear shrinkage was up to 5% more than that of the bulk. The features were
shown to be stable during pyrolysis up to 1000oC and stable at operating temperatures up to 1000oC.
A constant number Monte Carlo simulation was used to describe the suspension behavior to confirm the empirical results from the physical experiments. The effects of Van der Waals forces, steric stabilization, depletion flocculation, as well as the physical impediment of entangled polymer chains were considered. A similar agglomeration behavior was shown in the simulations compared to the physical experiments.
This thesis shows that polymer-nanoparticle hybrid films are a compatible material for imprint lithography using appropriate suspension parameters. This is very important for a variety of applications and devices. Using imprint lithography to make these devices makes them cheaper and more accessible to the commercial market and can make a large number of theoretical devices a reality.Ph. D.
Sub-micron patterning is an integral part of making many modern technologies such as memory storage devices or integrated circuits. As this technology becomes smaller and smaller, the limiting factor for making these devices has become the ability to manufacture effectively at the appropriate scale. Traditional commercial manufacturing methods lack the resolution needed to attain small enough features. Manufacturing methods that can make small enough features are often either extremely expensive or offer incomplete control of the feature morphology. Imprint lithography is a high-throughput, inexpensive alternative to making sub-micron features that can be tailored to work with a variety of materials. Imprint lithography is simple process in which a patterned stamp is pressed into a softened film of material in order to transfer the pattern of the stamp onto that material. Traditionally, imprint lithography works best with polymers and researchers have struggled to pattern nanoparticle-based materials. This work has achieved high-fidelity pattern transfer onto polymer-nanoparticle hybrid films with feature sizes on the same order as the polymer films found reported in literature. The polymer-nanoparticle hybrid was realized by creating a liquid suspension of functionalized ZnO nanoparticles and poly(methyl methacrylate) (PMMA) in a solvent. The ZnO particles were functionalized by adding nonanoic acid, allowing the normally polar particles to disperse in the non-polar solvent needed to dissolve the PMMA. This suspension was spread onto a glass substrate, imprinted with a patterned stamp, allowed to dry, and was demolded. The final result was the successful transfer of features ranging from 250 nm to 1 μm in size with good fidelity. The effect of the ZnO content as well as the method of combining the suspension components on the feature fidelity was studied. To help prove the broad applicability of this imprint method, it was adapted for use with polymer-derived ceramics. Additionally, a computer simulation was developed to help understand the behavior of the nanoparticle-polymer suspension during the imprint process.
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Ostler, Jeffery Brent Jr. "Characterization of Pol IV and Pol V-Dependent Non-Coding RNAs Derived from aGeminivirus Genome." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492698361649423.
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Drzic, Juraj. "The synthesis of 1,4-bis(2-(4-(4-fluorobenzoyl)phenoxyethoxy)benzene and poly(aralkyl ether)s derived from 1,4-bis(2-tosyloxyethoxy)benzene." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1401459744.
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GARREAU, SEBASTIEN. "Etude des potentialites du poly(3,4-ethylenedioxythiophene) (pedt) et de ses derives a travers les spectroscopies optiques et vibrationnelles." Nantes, 2000. http://www.theses.fr/2000NANT2056.
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Les proprietes optiques et vibrationnelles du pedt et de certains derives sont etudiees, au moyen de spectroscopies optiques : diffusion raman, absorption infrarouge, absorption optique. Ces resultats permettent d'interpreter les modifications de structure electronique qui se produisent le long de la chaine polymere lors du dopage electrochimique, et d'en proposer un mecanisme. Nous presentons tout d'abord une etude optique du polymere synthetise par voie electrochimique, puis celle des proprietes d'un polymere resultant d'une synthese chimique. Nous presentons egalement l'etude du polymere synthetise a l'etat neutre. Ensuite sont presentees la synthese d'un compose intrinsequement soluble, comportant une chaine alkyle avec 14 carbones, et l'etude de ses proprietes optiques, afin de degager l'influence de la chaine laterale sur ces proprietes. Des calculs de dynamique moleculaire sont effectues afin de permettre une interpretation en termes de modes de vibrations de ces experiences, ce qui conduit alors a la proposition d'un mecanisme d'oxydation des polymeres. L'etude de l'influence du groupement lateral sur les proprietes du polymere a ete poursuivie sur d'autres derives comportant cette fois-ci une chaine alkoxy. Enfin, nous presentons la synthese de nanotubes de pedt ainsi que les premiers resultats obtenus dans cette nouvelle orientation.
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Yang, Jinlian III. "Part I: Synthesis of Aromatic Polyketones Via Soluble Precursors Derived from Bis(A-Amininitrile)S; Part Ii: Modifications of Epoxy Resins with Functional Hyperbranched Poly(Arylene Ester)s." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30440.
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Part I: This part of the dissertation describes a new approach to high molecular weight aromatic polyketones via soluble precursors derived from bis(a-aminonitrile)s. Bis(a-aminonitrile)s were easily synthesized from dialdehydes and secondary amines in very high yield by the Strecker reaction. Polymerization of bis(a-aminonitrile)s with activated dihalides using NaH as base in DMF yielded soluble, high molecular weight polyaminonitriles, which were hydrolyzed in acidic conditions to produce the corresponding polyketones. A novel approach to the synthesis of high molecular weight wholly aromatic polyketones without ether linkages or alkyl substituents in the polymeric backbones was demonstrated. These polyketones displayed excellent thermal properties and solvent resistance. A very efficient synthesis for diphenol and activated dihalide monomers containing keto groups was also developed based on a-aminonitrile chemistry. Novel activated dihalide monomers were obtained in quantitative yields. This method is suitable for any activated dihalide by reaction with 2 equivalents of 4-fluorobenzylaminonitrile and NaH, followed by hydrolysis to produce a new monomer with two more p-fluorobenzoyl units. For the synthesis of polyaminonitriles containing ether linkages in the polymeric backbone, only low to medium molecular weight polymers were obtained. The model studies proved that the carbanions of the aminonitriles can react with ether linkages to form more stable phenoxide anions and cause the termination of the polymerization.
Part II: Functional hyperbranched poly(arylene ester)s were synthesized by thermal polymerization of 5-acetoxyisophthalic acid or 3,5-diacetoxybenzoic acid. Carboxylic terminated hyperbranched copolyesters were also synthesized by copolymerization of 5-acetoxyisophthalic acid and 3-hydroxybenzoic acid using different molar ratios of these two monomers. Both carboxylic acid and phenolic terminated hyperbranched polyesters were functionalized with different reactive groups. The carboxyl terminated hyperbranched poly(arylene ester)s were successfully used to modify inherently brittle epoxy resins. The hyperbranched polymers were chemically incorporated into the epoxy networks using triphenylphosphine (TPP) as a catalyst and 4,4'-diaminodiphenyl sulfone (DDS) as a curing agent. The chemistry and the proper formation of crosslinked networks were confirmed by solution 1H NMR, solid state CPMAS 13C NMR, kinetic FTIR spectroscopes and gel fraction analysis. Fracture toughness was improved without sacrificing thermal properties. The fracture toughness K1C values of the modified epoxies were found to be a function of the percentage loading, the molecular weights and the proportion of linear units of hyperbranched polyesters. Because the carboxylic acid terminated hyperbranched poly(arylene ester)s were immiscible with the commercially available epoxy EPON 828, the percentage loadings of hyperbranched modifiers were limited and the processibility of epoxy resins was difficult, especially at high percentage loadings of hyperbranched modifiers. These problems could be solved using phenolic terminated hyperbranched poly(arylene ester)s, which are more soluble in epoxy resins.Ph. D.
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Escobar, Domínguez María Gisela. "Incursiones urbanas en Poble Nou: imágenes y experiencias desde la mirada cenital y la mirada impura en un territorio en transformación." Doctoral thesis, Universitat Autònoma de Barcelona, 2009. http://hdl.handle.net/10803/5467.
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Este ejercicio de conocimiento, donde la ciudad no deja de ser un pretexto, apuesta por reivindicar la subjetividad y la experiencia desde el lugar del sujeto en la producción y la interpretación de los espacios. Este sujeto soy yo misma, en derivas a través de un ejercicio de conocimiento situado y en derivas a través de las calles del barrio de Poble Nou en Barcelona, dejándome llevar por mis sentidos y percepciones. En este ejercicio, intento proponer una epistemología y una práctica nómada donde el acto mismo de deambular no solo implica un gusto por las errancias sino la inconformidad con los espacios llenos y la centralidad dominante.La subjetividad nómada otorga un lugar preferente a los recorridos a través de las imágenes, las metáforas y la estética como formas que proponen sentidos sociales no limitados por las constricciones gramaticales. Con la recuperación del giro visual intento problematizar la ciudad desde lo visible, en lugar de pensarla únicamente como lugar geográfico; en otras palabras, proponer la ciudad como espacio de posibilidad donde las cosas se presentan a nuestras miradas y devienen producidas y atravesadas por nuestras experiencias.
Paralelamente, el giro visual pone al descubierto cómo los mecanismos del poder actúan bajo otros procedimientos de subjetivación y performativización distintos a los del entramando discursivo, los cuales circulan en nuestra cotidianidad bajo los matices de la imagen global. En el barrio de Poble Nou, la imagen se presenta como un objeto que circula tanto a nivel macro como micropolítico: desde la imagen-modelo de ciudad que se presenta bajo el slogan de <
1.- Cartografías de la mirada cenital: es la figuración del ideal de verdad absoluta y de pretendida universalidad cuando intenta abarcar el territorio en conjunto y simular un mundo a escala, desconfiando de las prácticas cotidianas, subjetivas y plurales. Este espacio sedimenta en el proyecto 22@ de Poble Nou y se recorre a través de cuatro hitos: a.) el ojo divino, b.) la promesa de los dispositivos visuales, c.) miradas-otro y espacios subalternos y d.) las cartografías racionales.
2.- Escenario de la mirada impura: con esta metáfora provocadora problematizo la idea de pureza que subyace a la pretensión de verdad que pretende datos descontaminados de los sentidos, para proponer la impureza como implicación de nuestro cuerpo en la comprensión del mundo desde un pensamiento mestizo, experiencial, imaginario y afectivo. Desde aquí propongo un giro al modelo cenital de enunciar los espacios urbanos para pensar en los sujetos al ras del suelo. Este escenario se recorre a través de los siguientes hitos: a.) lugares de la mirada, b.) cartografías contrahegemónicas, c.) la ciudad es una forma y d.) política de la experiencia estética.
Estas dos perspectivas son retratadas a través de las reflexiones de mis experiencias y derivas por las calles de Poble Nou, donde los objetos urbanos motivan las interpretaciones de un barrio en acelerada transformación urbanística frente a la potencia transformadora de sus habitantes.
In this research, where the city is a pretext, I'm interested to claim subjectivity and experience in the production and interpretation of urban spaces through an exercise of situated knowledge. The subject it's me; in wanderings through the streets of Poble Nou's neighbourhood in Barcelona, leaving me by my senses and perceptions.
I suggest not only a nomadic practice but a nomadic epistemology because wandering proposes the nonconformity with the hegemonic and dominant centrality. This nomadic subjectivity offers a preferential position to images, metaphors and aesthetics as forms that propose social senses beyond the limits of grammatical constructions.
Through the visual turn, I try to make problematic the city from its visible objects, instead of thinking it as just a geographical place; in other words, I intend to propose the city as a possible space where the objects are presented to our views while they are crossed by our experiences. By another hand, visual turn also reveals how the mechanisms of power creates performance meanings that are not in the frame of discursive construction, but circulates in our ordinary live under the shades of global image.
In my comprehension to Poble Nou, the images are process that circulates in a macro and micro-political level: from the global image-model where the city is presented under the slogan of <
To clarify the tension among the global power and practices of every day life I propose a trip through two metaphors that also figures two perspectives to the city:
1.- Zenithal view cartographies: is the figuration of the truly absolute ideal and supposed universality of the knowledge that pretends to cover the territory simulating a world to scale, distrusting the plural, subjective and routine practices in the cities. This space is portrayed by the Poble Nou/22@ project and crosses by four points: a.) the divine eye, b.) the promise of the visual devices, c.) subordinates spaces and d.) rational cartographies.
2.- Impure view setting: this provocative metaphor makes problematic the purity that underlies scientific pretension and proposes impurity as implication of our body in the comprehension of the world from a <
In both perspectives urban objects motivate the interpretations of a gentrificated neighbourhood in a quickly urban transformation, in front of the political potency of their inhabitants.
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Mosblech, Alina [Verfasser], Ingo [Akademischer Betreuer] Heilmann, Andrea [Akademischer Betreuer] Polle, and Gerhard [Akademischer Betreuer] Braus. "Requirement of phosphoinositol-derived signals in the wounding response of Arabidopsis thaliana / Alina Mosblech. Gutachter: Ingo Heilmann ; Andrea Polle ; Gerhard Braus. Betreuer: Ingo Heilmann." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1043068481/34.
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Morice, Pierre-Marie. "Evaluation de la déficience de la recombinaison homologue et de la réponse des tumeurs ovariennes aux inhibiteurs de PARP grâce à l'utilisation de modèles de culture 3D en vue du développement d'un test prédictif Identifying eligible patients to PARP inhibitors: from NGS-based tests to promising 3D functional assays Automated scoring for assessment of RAD51-mediated homologous recombination in patient-derived tumor organoids of ovarian cancers Risk of myelodysplastic syndrome and acute myeloid leukemia related to PARP inhibitors: a combined approach using a safety meta-analysis of placebo randomized controlled trials and the World Health Organization's pharmacovigilance database The long non-coding RNA ‘UCA1’ modulates the response to chemotherapy of ovarian cancer through direct binding to miR-27a-5p and control of UBE2N levels." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMC414.
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Chaque année, plus de 150 000 décès sont associés aux cancers épithéliaux de l’ovaire dans le monde, notamment en raison du développement d’une résistance à la chimiothérapie. Environ la moitié de ces cancers présentent des altérations moléculaires provoquant une déficience de la réparation de l’ADN par recombinaison homologue (HRD) qui les sensibilise à l’action des inhibiteurs de la protéine PARP (PARPi). A ce jour, il n’existe pas de test capable d’appréhender le phénotype HRD dans sa globalité, limitant ainsi l’accès à ces traitements. Dans ce contexte, nous avons entrepris de mettre au point des tests fonctionnels basés sur l’utilisation d’explants tumoraux tranchés puis sur l’utilisation d’organoïdes tumoraux dérivés de tumeurs ovariennes de patientes chimio-naïves ou antérieurement traitées. La culture d’explants s’est révélée inappropriée pour la réalisation de ces tests et nous avons alors focalisé nos travaux sur les organoïdes tumoraux. Ces derniers ont été exposés au carboplatine (traitement de 1e ligne) et à deux inhibiteurs de PARP (l’olaparib et le niraparib) utilisés en traitement d’entretien. En parallèle, nous avons collecté les données cliniques des patientes (survie, intervalle sans platine, RECIST, traitements) afin d’évaluer le potentiel prédictif de ces modèles. Les organoïdes tumoraux établis ont répondu de façon hétérogène aux différents médicaments testés, et nos résultats montrent que les tests réalisés sur les organoïdes sont capables d’identifier des patientes présentant un niveau de résistance élevé au carboplatine, suggérant que ce test fonctionnel pourrait présenter un intérêt prédictif vis-à-vis de ce médicament. Concernant le potentiel prédictif des organoïdes vis-à-vis des PARPi, des profils de sensibilité variés ont été identifiés, mais la corrélation avec la réponse clinique reste à établir par des études menées sur des échantillons de tumeurs issus de patientes traitées par ces médicamentsWorldwide each year, more than 150 000 women die from epithelial ovarian cancer largely due to emergence of resistance to chemotherapy. Approximately half of these cancers display molecular alterations that cause deficiency of DNA repair via homologous recombination (HRD), which confer sensitivity to PARP protein inhibitors (PARPi). To date, there is no test capable of fully identifying the HRD phenotype, thus limiting access to these treatments. In this context, we are developing functional assays based on the use of tumor explant slices and then, on the use of tumor organoids derived from ovarian tumors of chemotherapy-naive or previously treated patients. The culture of explants was unsuitable for this application and we then focused our work on tumor organoids. Tumor organoids were exposed to carboplatin (first-line treatment) and two PARP inhibitors (olaparib and niraparib) used for maintenance therapy. In parallel, we collected clinical data from patients (survival, platinum-free interval, RECIST, treatments) to evaluate the predictive potential of these models. The established tumor organoids responded heterogeneously to different drugs, and our results show that the organoid-based assay is capable of identifying patients highly resistant to carboplatin, suggesting that this functional assay could have a predictive value for patients treated with carboplatin. Regarding the potential of organoids in predicting PARPi response, multiple sensitivity profiles have been identified, but the correlation with clinical response has yet to be determined by studies conducted on tumor samples from patients treated with these drugs
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Lakay, Eugene Marlin. "Novel ion-exchange materials derived from poly(styrene-co-maleimide) and a study of the extraction and recovery of gold (III) chloride from acidic solutions." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80148.
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Thesis (PhD)--Stellenbosch University, 2013.ENGLISH ABSTRACT: In this study an economical, environmentally friendly, selective and efficient process for the extraction and recovery of [AuCl4]- from aqueous acidic chloride-rich solutions, particularly those aqueous solutions having low concentrations of the precious metal complexes has been investigated. Functionalized poly(styrene-co-maleimide) (PSMI) nanoparticles were synthesized by thermal imidization of the poly(styrene-co-maleic anhydride) (PSMA) copolymer with 3-N,N-dimethylaminopropylamine. Stable water-based dispersions were obtained containing spherical, monodisperse PSMI nanoparticles with a narrow size-distribution and average diameters of 50 ± 5 nm. The specific surface area of the bulk PSMI nanoparticles is 88.1 ± 2.2 m2/g with an average pore diameter of 82.3 Å. 13C NMR, FTIR and elemental analyses confirmed the successful and complete conversion of PSMA into the PSMI derivative. The functionalized PSMI nanoparticles synthesized were investigated as a novel anion-exchange material for the extraction of [AuCl4]- ions from aqueous acidic solutions. Batch sorption studies were carried out as a function of various parameters, such as initial gold concentration, PSMI mass, contact time and agitation rate. The [AuCl4]- extraction occurred with extremely fast sorption kinetics and is dependent on the rate of agitation during the batch sorption process. The functionalized PSMI nanoparticles show a maximum gold loading capacity of 1.76 mmol/g (347.7 mg/g). Langmuir and Freundlich isotherm models were applied to analyze the experimental sorption data. The best model describing the sorption process is given by the Langmuir model. Desorption efficiencies of about 80 % and 93 % were obtained using acidified thiourea (0.25 M thiourea/2 M HCl) and a mixture of 10 M HNO3/0.5 HCl as elutant solutions, respectively. X-ray photoelectron spectroscopy (XPS) analysis unambiguously confirms that the immobilized gold species exists in several oxidation states of 0, +I and +III on the PSMI nanoparticles. This proves that the [AuCl4]- ions initially present in the gold feed solutions unfortunately are subject to a reduction phenomenon on the surface of the functionalized PSMI nanoparticles. The existence of the various gold species contributed significantly to poor desorption efficiencies. In addition to PSMI nanoparticles, micro- to millimeter size PSMI resin beads was prepared by an electrospray methodology. This allows for a wide range of PSMI spherical and quasi-spherical bead diameters of shape to be prepared by manipulation of the experimental conditions employed during the electrospray process, such as the concentration of the PSMI in solution, the capillary tip-to-collector distance, flow rate and the applied voltage. 13C NMR and FTIR spectroscopy analyses show that the electrospray methodology allows PSMI resin beads preparation without any change in chemical composition of the PSMI material. Surface area and porosity analysis shows that 450 μm and 1620 μm PSMI beads selected for use in the gold extraction experiments are microporous and have BET specific surface areas of 2.8 ± 0.4 m2/g and 2.0 ± 0.1 m2/g, respectively. Micro- to millimeter size PSMI resin beads of 450 μm and 1620 μm diameter were tested as potential anion-exchange resins for the extraction of [AuCl4]- from aqueous acidic solutions. The time-dependent studies reveal that the extent of gold uptake increases with an increase in contact time and is dependent on the gold concentration in the [AuCl4]- feed solutions. A maximum loading capacity of 120.7 mg/g and 98.16 mg/g was attained for the 450 μm and 1620 μm resin beads, respectively. The experimental sorption data followed a linear trend consistent with a Freundlich sorption model. This sorption trend for [AuCl4]- suggests that a multi-layer sorption process predominates. Desorption of immobilized gold species from the loaded PSMI resin beads was investigated using various elutants such as HCl, HNO3, thiourea, NaCN and NaOH solutions. The best results were obtained using a mixture of 10 M HNO3/0.5 M HCl as elutant with a desorption efficiency of about 97%. Finally, superparamagnetic magnetite (Fe3O4) nanoparticles with a high degree of crystallinity and phase purity were synthesized by a chemical co-precipitation of Fe2+ and Fe3+ salts. The average diameters of the obtained Fe3O4 nanoparticles were about 7 – 8 nm. The Fe3O4 nanoparticles were coated with oleic acid surfactant molecules and used as seed particles for the preparation of 50 nm diameter magnetic PSMI nanoparticles via an in situ imidization reaction. TEM analysis confirmed that the magnetically responsive PSMI nanoparticles consist of magnetite core-polymer shell structure, although more work is required to perfect such materials.
AFRIKAANSE OPSOMMING: In hierdie studie is ‘n ekonomiese, omgewings vriendelike, seleketiewe en effektiewe proses vir die ekstraksie en herwinning van [AuCl4]- uit suur chloried-ryke oplossings, spesifiek oplossings van lae konsentrasies van edel metal komplekse was bestudeer. Gefunksionaliseerde poli(stireen-ko-maleïmied) (PSMI) nanopartikels was gesintetiseer deur middel van termiese imidisasie van die poli(stireen-ko-maleïk anhidried) kopolimeer met 3-N,N-dimetielaminopropielamien. Stabiele dispersies in water was gevind wat soos sweriese mono-disperse PSMI nanopartikels met ‘n noue partikel-grootte verspreiding met ‘n gemiddelde deursnee van 50 ± 5 nm. Die spesifieke oppervlak area van die massa PSMI nanopartikels is 88.1 ± 2.2 m2/g met ‘n gemiddelde porie-grootte van 82.3 Å. 13C NMR, FTIR en elementêre analiese bevestig die suksesvolle en volledige omskakeling van PSMA na PSMI. Die gefunksionaliseerde PSMI nanopartikels was bestudeer as ‘n nuwe anion-uitruil material vir die ekstraksie van [AuCl4]- ione uit suur oplossings. Stel sorpsie studies was uitgevoer as ‘n funksie van verskeie parameters soos onder andere die goud konentrasie in oplossing, PSMI massa, kontak tyd en ‘n mengings tempo. Die [AuCl4]- ekstraksie gebeur met ‘n geweldige sorpsie kinetika en is afhanklik van die mengings tempo gedurende die stel sorpsie proses. Die gefunksionaliseerde PSMI nanopartikels het ‘n maksimum goud sorpsie kapsiteit van 1.76 mmol/g (347.7 mg/g). Langmuir en Freundlich isoterm modelle was gepas en geanaliseer op die experimentele sorpsie data waarvan die Langmuir isoterm model die data die beste gepas het. De-sorpsie effektiwiteit van ongeveer 80 % en 93% was vekry vir die aangesuurde thiourea (0.25 M thiourea/2 M HCl) en ‘n mengsel van 10 M HNO3/0.5 M HCl as elueer oplossings, onderskeidelik. X-straal foto-elektron spektroskopie (XPS) analiese bevestig ongetwydeld die geimmobileerde goud spesies in oksidasietoestande van 0, +I, en +III op die PSMI nanopartikels. Hierdie is bewyse dat die [AuCl4]- oorspronklik teenwoordig in die goud oplossings is onderhewe auto-reduksie fenomeen op die oppervlak van die gefunksionalieerde PSMI nanopartikels. Die bestaan van verskeie goud spesies dra by tot die power de-sorpsie effektiwiteit van ge-immobiliseerde goud. Bykomend tot die nanopartikels is mikro- tot millimeter grootte PSMI partikels voorberei met ‘n elektro-sproei proses. Hierdie metode stel ons instaat om ‘n wye reeks sferiese en quasi-sferiese PSMI partikel se deersnee voorteberei. Deur die manupulasie van die eksperimentele kondisies gedurende die elektro-sproei proses, soos die konsentrasie van die PSMI in oplossing, die kapilêre punt-tot-ontvanger afstant, vloeispoed en die toegepasde potensiaal. 13C KMR en FTIR spectroskopiese analiese wys dat die elektro-sproei proses die PSMI partikel bereiding toelaat sonder enige veranderinge in die chemiese samestelling van die PSMI materiaal. Oppervlak area en porie-grootte analise wys dat 450lksdfhld en dskl jmm partikels gebruik in die goud ekstraksie eksperimente is mikro-porieës en het spesifieke oppervlak-areas van 2.8 ± 0.4 m2/g en 2.0 ± 0.1 m2/g onderskeidelik. Mikro- tot millimeter grootte poli(stireen-ko-maleimied) (PSMI) partikels van 450 μm en 1620 μm deursnee was getoets as potensieele anion-uitruilings-hars vir die ekstraksie van [AuCl4]- vanuit suur oplossings. Die tyd afhanklike studies gee aanduiding dat die mate van goud opname toeneem met ‘n toename in kontak-tyd en is afhanklik van die goud konsentrasie in die [AuCl4]- oplossings. ‘n Maksimum opname-kapasiteit van 120.7 mg/g en 98.2 mg/g was verkry vir die 450 μm en 1620 μm hars partikels onderskeidelik. Die eksperimentele sorpsie-data volg ‘n lineêre neiging in ooreenstemming met die Freundlich model. Die sorpsie neiging van [AuCl4]- dui aan dat ‘n meervuldige laag sorpsie proses domineer. De-sorpsie van die geimobiliseerde goud spesies vanaf die PSMI hars partikels was bestudeer deur gebruik te maak van verskeie elueermiddels soos HCl, HNO3, thiourea, NaCN en NaOH oplossings. Die beste resultate is verkry deur ‘n mengsel te gebruik van 10M HNO3/0.5M HCl as elueermiddel met n de-sorpsie effektiviteit van ongeveer 97%. Superparamagnetiese magnetiet (Fe3O4) nanopartikels met ‘n hoë graad van kristaliniteit en fase-reinheid was voorberei deur ‘n chemiese ko-neerslagvorming van Fe2+ en Fe3+ soute. Die gemiddelde deursnee van die Fe3O4 nanopartikels was ongeveer 7 – 8 nm. Die Fe3O4 nanopartikels was omhul met oleic suur benatter molekules wat gebruik word as saadjies vir voorbereiding van 50 nm deursnee-magnetiese PSMI nanopartikels deur middel van ‘n imidisasie reaksie. TEM analiese bevestig dat die magnetiese PSMI partikels nanopartikels bestaan uit ‘n magnetiet-kern polimeer-skil struktuur.
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Mailley, Pascal. "Immobilisation d'enzymes dans des poly(pyrrole-amphiphiles) : caractérisation et application à la biodétection ampérométrique du glucose." Université Joseph Fourier (Grenoble ; 1971-2015), 1995. http://www.theses.fr/1995GRE10160.
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Les biocapteurs amperometriques decrits dans ce travail sont des dispositifs analytiques bases sur l'immobilisation d'une enzyme a la surface d'une electrode. Les performances du biocapteur sont fortement conditionnees par la methode d'immobilisation mise en uvre ainsi que par les caracteristiques de la matrice hote qui en resulte. Dans ce contexte, ce travail developpe une nouvelle technique d'immobilisation electrochimique d'enzyme basee sur les proprietes remarquables d'une famille de derives n-substitues amphiphiles du pyrrole. Les tres larges potentialites de cette technique, qui fait appel a l'electropolymerisation d'un depot adherent d'enzyme et de monomere, ont ete demontrees pour une serie de cinq enzymes presentant des tailles et des points isoelectriques tres differents. Les performances analytiques des differents biocapteurs ont ete comparees et correlees a la permeabilite des matrices polymeres hotes. Le monomere presentant les meilleures potentialites (12-(pyrrol, yl)dodecyltriethylammonium) a ensuite ete applique a l'immobilisation de la glucose oxydase. Apres optimisation des parametres operationnels (temperature, ph,) et structuraux (composition du bio-materiau), les caracteristiques metrologiques des biocapteurs a la glucose ont ete modulees grace a l'elaboration de structures multicouches. Finalement, trois strategies, basees sur l'optimisation de la detection amperometrique ou sur l'utilisation de membranes semi-permeables, ont ete etudiees de maniere a augmenter la selectivite des biocapteurs au glucose vis-a-vis des interferents
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Yang, Zheng, and 楊爭. "Identification of non-HIV-derived (poly)peptides as primary immunogens for HIV-1 vaccine development and localization of two dominant ADCC epitopes on hemagglutinin antigen of pandemic H1N1 influenza virus." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208007.
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Development of effective vaccines against mutable viruses (i.e HIV-1 and influenza) remains a big challenge. Antibody-dependent cell-mediated cytotoxicity (ADCC) has been found to be a key component of immune protection against viral infections in vivo. Therefore, vaccine immunogens that elicit broadly neutralizing antibodies with high ADCC are desired for vaccine development. This study is to identify primary immunogens that can initiate somatic maturation of germline antibodies of known broadly neutralizing HIV-1 antibodies (bnAbs) for HIV vaccine development and to localize dominant ADCC epitopes on hemagglutinin (HA) of pandemic H1N1 influenza virus for development of a flu vaccine.
Based on the observations that known HIV-1 bnAbs have extensive somatic mutation compared to their germline versions and that HIV-1 envelope (Env) glycoprotein lacks measurable binding to putative germline antibodies of known bnAbs, we hypothesized that non-HIV-derived (poly)peptides may serve as primary immunogens to trigger somatic maturation of germline antibodies of bnAbs, leading to elicitation of intermediate antibodies (iAbs) that can further mature to HIV-1 bnAbs upon Env vaccination or HIV-1 infection. Using b12 as a model bnAb, we identified five non-HIV-derived (poly)peptides that bound to putative b12 germline and iAbs, and immunized rabbits with the (poly)peptide priming followed by Env boosting. Rabbit immunization with (poly)peptides alone induced high titers of antibodies that were cross-reactive with gp140SF162 trimer and resurfaced Env RSC3, and the serum IgGs neutralized SF162 and JRFL. These results suggest that the (poly)peptides might structurally mimic CD4bs of Env. Priming rabbits with (poly)peptides followed by boosts with gp140SF162 and RSC3 resulted in antibodies capable of competing with b12 for binding to gp140SF162 trimer and neutralizing cross-clade isolates, while control rabbits without priming produced antibodies that were unable to compete with b12 for gp140SF162 trimer binding, and the serum IgGs neutralized only 3 clade B isolates. Our results provide proof of concept that non-HIV-derived (poly)peptides may serve as primary vaccine immunogens to initiate guided immune responses towards bnAbs.
HA protein has high level of immunogenicity and considered the most important target for immune protection against influenza virus infection. Several potent HA-specific bnAbs have been reported with their conserved neutralizing epitopes revealed, but there has been no report so far about ADCC epitopes on HA. Using yeast display and flow cytometry assisted cell sorting, we mapped the epitope of convalescent plasma IgGs with different ADCC activity, we identified two dominant ADCC epitopes, designated HA-E1 [AA92-117] and HA-E2 (AA 124-159), on HA of 2009 pandemic H1N1 influenza virus. E1 and E2 overlapped with the immunodominant epitopes of HA. Depletion of purified patient plasma IgGs with yeast cells expressing E1 or E2 peptides decreased ADCC activity of the IgGs. E1 and E2 sequences are highly conserved in H1N1 strains, but less so in other subtypes of influenza A viruses. Our study may aid in designing immunogens that can elicit antibodies with high ADCC activity. Vaccine immunogens designed to include the structural determinants of potent bnAbs and ADCC epitopes may confer a comprehensive immune protection against influenza virus infection.published_or_final_version
Microbiology
Doctoral
Doctor of Philosophy
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Romagnoli, Barbara. "Synthesis and characterisation of a novel class of chiral poly(aromatic aminde) dendrimers incorporating a C₃-symmetric core system derived from the α-amino acids L- and D-serine." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250671.
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COGNAULT, SOPHIE. "Importance de l'interaction entre les acides gras poly-insatures et la vitamine e dans la croissance tumorale mammaire. Role des derives peroxydes mis en evidence dans le modele de tumeurs chimio-induites chez la ratte." Paris 7, 1999. http://www.theses.fr/1999PA077054.
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Ce travail vise a mieux comprendre le role des acides gras poly-insatures (agpi) dans la cancerogenese en utilisant un modele de tumeurs mammaires chimio-induites chez la ratte. Nous avons fait l'hypothese que les agpi modulent la croissance tumorale via la formation de peroxydes et que toute augmentation in vivo de leur production s'accompagne d'une reduction de la croissance tumorale. Pour verifier cela, nous avons module dans le regime la source de produits peroxydables (riche ou pauvre en agpi) et/ou la source de produits inhibant (anti-oxydant) ou favorisant (oxydant) la peroxydation. Nous avons observe que la presence conjointe d'une huile riche en agpi et d'un anti-oxydant, la vitamine e, augmente la croissance tumorale en comparaison du meme regime sans vitamine e. A l'inverse, l'apport d'oxydants reduit la croissance tumorale. De plus, aucune variation n'est observee selon le statut oxydant si l'huile riche en agpi est remplacee par une huile pauvre en agpi. Ces resultats montrent l'importance du statut oxydant du regime dans l'effet des agpi sur la cancerogenese et suggerent une implication de la lipoperoxydation. Les analyses biochimiques et de croissance cellulaire semblent indiquer que la production de peroxydes aurait une action cytotoxique sur les cellules tumorales en induisant l'apoptose, sans affecter la proliferation cellulaire. Par ailleurs, les genes de la cycline d 1 et de l'acide gras synthase, impliques dans la proliferation ou la survie des cellules tumorales, ne constituent pas des marqueurs de l'action des agpi car leur expression n'est pas modulable in vivo. Ces donnees montrent la necessite de prendre en compte l'influence que des nutriments comme les agpi et la vitamine e peuvent avoir l'un sur l'autre en matiere de controle de la cancerogenese. Elles fournissent des informations utiles a la conception de futures etudes, en termes de facteurs a analyser, de marqueurs nutritionnels exploitables ou de marqueurs moleculaires non pertinents.
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Schuler, Tunísia Eufrausino. "Síntese e caracterização de copolímeros randônicos poli[bis-(fenilenovinileno)-stat-(1,8-bis-(2,6-dioximetano-1,4-fenilenovinileno)-dioxioctano)-1,4-fenileno)] e aplicação em diodos emissores de luz orgânicos (OLEDs)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-02102008-174734/.
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Com o intuito de melhorar a eficiência dos dispositivos emissores de luz poliméricos uma das técnicas utilizadas é o confinamento da conjugação, diminuindo as perdas de energia em sítios de extinção, como fins de cadeia, defeitos ou armadilhas. Além disso, o confinamento quântico permite o controle do comprimento de onda emissivo desses materiais. Um dos mecanismos para o confinamento é a copolimerização, por meio da qual bloco conjugados são inseridos como grupos laterais na cadeia principal ou espaçadores nãoconjugados são inseridos ao longo da cadeia principal conjugada, limitando o comprimento da conjugação. O presente trabalho visou sintetizar e estudar as propriedades de copolímeros estatísticos derivados do PPV contendo segmentos com diferentes graus de conjugação distribuídos aleatoriamente na cadeia e limitados por segmentos não conjugados, e o estudo do comportamento desses materiais como camada ativa em dispositivos emissores de luz (PLEDs). Para a obtenção dos copolímeros randômicos poli[bis-(fenilenovinileno)-stat-(1,8-bis- (2,6-dioximetano-1,4- fenilenovinileno)-dioxioctano)-1,4-fenileno) (RBPV-DODM-PPV) utilizou-se a rota de Wittig, a partir dos monômeros: tereftaldeído (um dialdeído completamente conjugado), 1,8 bis (4 formil 2,6 dimetoxifenoxi) octano (um dialdeído interespaçado por uma cadeia saturada de oitometilenos) e o dicloreto de 1,4 bis (trifenilfosfôniometil) benzeno. Três razões molares x:y dos monômeros dialdeídos foram utilizadas para sintetizar os polímeros randômicos, obtendo-se diferentes proporções e tamanhos de segmentos conjugados distribuídos aleatoriamente nas cadeias poliméricas. Os materiais foram caracterizados por espectroscopia de ressonância magnética nuclear (RMN), no infravermelho, UV-visível, e fluorescência. A técnica de GPC foi utilizada para obtenção das massas moleculares e medidas de Tg foram realizadas por meio de DSC. As propriedades físico-químicas desses materiais foram analisadas em função das razões molares x:y utilizadas nas sínteses. E um estudo estatístico foi realizado para verificar as probabilidades de distribuição dos diferentes segmentos conjugados ao longo da cadeia em função dessas razões. Um estudo da morfologia e espessura dos filmes poliméricos em função dos parâmetros de deposição foi realizado a fim de descobrir as melhores condições para se obter filmes homogêneos e com espessuras da ordem de 20 a 60nm, necessários para alcançar melhores eficiências nos diodos emissores de luz poliméricos (PLEDs). Para a fabricação dos PLEDs foram utilizados ITO e Al como anodo e catodo, respectivamente, e uma camada de 20nm do polímero estatístico como matriz ativa e eletroluminescente. Para facilitar o transporte de portadores de cargas, camadas de PEDOT:PSS e BPBD foram colocadas entre o filme polimérico e os eletrodos. Também foram realizados testes com filmes da molécula Alq-3 como camada transportador-injetora de elétrons. Os dispositivos apresentaram eletroluminescência EL em quase toda a faixa do espectro visível, com máximos na região do ciano, para o copolímero R55 e na região do verde, para o copolímero p37. Baseado no mecanismo de Forster de transferência de energia, concluímos que os filmes desses polímeros estatísticos comportam-se como sistema hospedeiro-hóspede, devido a sobreposição parcial dos espectros de absorção e emissão dos polímeros, ocorrendo a transferência dos excitons-singletos dos segmentos de maior gap para os de menor gap, e, assim, o deslocamento dos centros emissivos para o vermelho e o aumento da eficiência dos dispositivos.In order to improve the efficiency of polymeric light-emitting devices one of the techniques used is the conjugation confinement, decreasing the losses of energy in quenching sites, such as chain ends, defects or impurities. Moreover, the quantum confinement allows control the emissive wavelength of these materials. One of the confinement mechanisms is the copolymerization, which conjugated blocks are inserted as side groups in the main chain or non-conjugated spacers are inserted along the conjugated main chain, limiting the conjugation length. This study aimed synthesize and study the properties of random copolymers containing segments with different conjugation degrees randomly distributed in the chain and limited by no conjugated segments, and the study of the behaviour of these materials as active layer in a light emitting devices (PLEDs). To obtain random copolymers of poly [bis (fenilenovinileno)-stat-(1,8-bis-(2,6-dioximetano- 1, 4 - fenilenovinileno)-dioxioctano) -1,4-phenylene) (RBPV-DODM - PPV) have been used the Wittig route, from monomers: terephtaldeyde (a dialdeyde completely conjugated), 1.8 - bis (4 - formyl - 2.6 - dimethoxiphenoxi) octane (a dialdeyde interspaced by a saturated chain of eight methylene) and dichloride of 1.4 - a (triphenylphosphoniomethil) benzene. Three molars reasons x: y of dialdeydes monomers were used to synthesize the random polymers, obtaining various proportions and sizes of conjugated segments randomly distributed in the polymer chains. Infrared (IR) and ultravioletvisible (UVvis)spectroscopies, hydrogen nuclear magnetic resonance (1HNMR) spectrometry and differential scanning calorimetry(DSC) were used to characterize the prepared copolymersstructures. Polymers molecular weights were determined by gel permeation chromatography (GPC). The physical-chemical properties of these materials were analyzed by the molars reasons x: y used in the synthesis. And a statistical study was conducted to ascertain the probability of distribution of the various conjugated segments along the chain by these reasons. A study of the morphology and thickness of the polymer films as a function of the parameters of deposition was conducted in order to find out the best conditions to obtain homogeneous films with thickness in the order of 20 to 60 nm, necessary to achieve the best efficiencies in the polymer light emitting diode (PLEDs). For the manufacture of PLEDs ITO and Al were used as anode and cathode respectively, and a layer of 20nm of the statistical polymer as active matrix and electroluminescent. To facilitate the transport of charge carriers, layers of PEDOT: PSS and BPBD were placed between the film and polymer electrodes. Tests were also carried out with films of the molecule Alq-3 as layer electron carrier / injector. The devices had electroluminescence EL in almost the entire range of the visible spectrum, with maximum in the region of cyan, for the copolymer R55 and in the green, for the copolymer p37. Based on the Forster mechanism of energy transfer, we find that the films of these statistical polymers behave themselves as host-guest system, due to partial overlap of absorption and emission spectra of the polymers, occurring the transfer of excitons-singletes of the segments with largest gap for the smaller gap, and thus the displacement of the emission centers for the red.
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Haji, mansor Muhammad. "Functionalized polymer implants for the trapping of glioblastoma cells Development of a non-toxic and non-denaturing formulation process for encapsulation of SDF-1α into PLGA/PEG-PLGA nanoparticles to achieve sustained release Reversing the Tumor Target: Establishment of a Tumor Trap." Thesis, Angers, 2019. http://www.theses.fr/2019ANGE0015.
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Le glioblastome (GBM) est la forme de cancer du cerveau la plus courante et la plus meurtrière. Sa nature diffusive entraine une impossibilité d’élimination complète par chirurgie. Une récidive de la tumeur chez ≥ 90% des patients peut être provoqué par des cellules GBM résiduelles se trouvant près du bord de la cavité de résection. Un implant pouvant libérer de manière durable la protéine SDF-1α, qui se lie aux récepteur CXCR4 à la surface des cellules GBM, peut être utile pour induire le recrutement des cellules GBM résiduelles, permettre leur élimination sélective et finalement réduire la récurrence de la tumeur. Dans ce travail, le SDF-1α a été initialement encapsulé dans des nanoparticules à base d'acide poly-lactique-co-glycolique (PLGA). Une efficacité d'encapsulation élevée (76%) a pu être obtenue en utilisant un processus simple de séparation de phase. Les nanoparticules chargées de SDF-1α ont ensuite été incorporées dans un scaffold à base de chitosan par électrofilage pour obtenir des implants nanofibreux imitant la structure de la matrice extracellulaire du cerveau. Une étude de libération in vitro a révélé que l'implant pouvait fournir une libération prolongée de SDF-1α jusqu'à 35 jours, utile pour établir un gradient de concentration de SDF-1α dans le cerveau et induire une attraction des cellules GBM. Une étude de biocompatibilité in vivo à 7 jours a révélé des signes d'inflammation locale sans aucun signe visible de détérioration clinique chez les sujets animaux. Une étude à 100 jours visant à confirmer l'innocuité in vivo des implants avant de passer aux études d'efficacité dans un modèle de résection GBM approprié est actuellement en coursGlioblastoma (GBM) is the most common and lethal form of brain cancer. The diffusive nature of GBM means the neoplastic tissue can not be removed completely by surgery. Often, residual GBM cells can be found close to the border of the resection cavity and these cells can multiply to cause tumor recurrence in ≥90% of GBM patients. An implant that can sustainably release chemoattractant molecules called stromal cell-derived factor-1α (SDF-1α), which bind selectively to CXCR4 receptors on the surface of GBM cells, may be useful for inducing chemotaxis and recruitment of the residual GBM cells. This may then give access to selective killing of the cells and ultimately reduce tumor recurrence. In this work, SDF-1α was initially encapsulated into poly-lactic-coglycolicacid (PLGA)-based nanoparticles. A high encapsulation efficiency (76%) could be achieved using a simple phase separation process. The SDF-1α-loaded nanoparticles were then incorporated into a chitosan-based scaffold by electrospinning to obtain nanofibrous implants that mimic the brain extracellular matrix structure. In vitro release study revealed that the implant could provide sustainedSDF-1α release for 5 weeks. The gradual SDF-1αrelease will be useful for establishing SDF-1α concentration gradients in the brain, which is critical for the chemotaxis of GBM cells. A 7-day in vivo biocompatibility study revealed evidence of inflammation at the implantation site without any visible signs of clinical deterioration in the animal subjects. A long-term study (100 days) aiming to confirm the in vivo safety of the implants before proceeding to efficacy studies in a suitable GBM resection model is currently underway
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Tseng, Feng-Po, and 曾峰柏. "Preparation, Property and Applications of Poly(oxyalkylene)amine Derived Polymers." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/43329820940408533814.
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博士國立交通大學
應用化學系
89
The object of this study was investigated the applications of different poly(oxyalkylene)amine derivatives in the field of compatibilizer, electrostatic dissipation and epoxy curing. The in situ formed poly(oxypropylene)-amide grafted polypropylene(PP-g-MA-co-POPs) were used as compatibilizers for the PA6/PP blends. The compatibilization effect was examined in terms of morphology, thermal and mechanical properties. Using these PP-g-MA-co-POP copolymers, the compatibilized blends show improvements in mechanical properties, including Izod impact strength and tensile toughness, over a conventional compatibilizer. The suitable molecular weight of the poly(oxypropylene) diamines in the range of 230 to 2000 is the key factor to act as an effective compatibilizer. During the compounding process, these compatibilizers further react with PA6 in situ to afford the mixture of PP-g-MA-co-POP-PA6, PP-g-MA-co-POP-co-PA6 and/or PP-g-MA-co-PA6 copolymers, which further improves the compatibilizing effect. However, the synthesized SMA-co-M-2070-co-DAP copolymers are less effective compatibilizers for the PA6/PS blends due to less interactions of M-2070 with PA6. The suitable molecular weight of the poly(oxyalkylene)amines and the PS backbone is the key factor to act as an effective compatibilizer. The electrostatic dissipating ability, probed by surface resistivity, of the poly(oxyalkylene)amine derived epoxies and polyesteramides is found to be affected by the nature, mobility and the weight content of poly(oxyethylene) segment in the polymer backbone, as well as the degree of crystallinity. The surface resistivity decrease is proportion to the nature, mobility and the weight content of poly(oxyethylene) segment and adversely affects by the degree of crystallinity. Comparing with PEG-2000 and ED-2001 derived polyesteramides, the presence of amide group can enhance the hydrophilic property. The polymer surfaces absorb moisture through hydrogen bonding by POE segment. The partial ionization of water into H＋ and OH－ promotes electronic conductivity. With a proper selection of mixed poly(oxyethylene-oxypropylene)diamine (25wt%) and 2-aminoethanol (9wt%), the DGEBA cured polymer was extremely ductile in appearance and shown over 500 % elongation at break under the mechanical tests. The high flexibility is rationalized by the balanced chemical structure of poly(oxyalkylene) segments and bisphenol-A distributed in a slightly crosslinking system. A family of novel Mannich bases were prepared from the Mannich reaction of phenols, formaldehyde, and poly(oxyalkylene)diamines with different molar ratios. The use of these novel Mannich bases for epoxy curing allowed us to study the structure/property relationship. By varying the ratio of phenols/amine and chemical structure of the starting poly(oxyalkylene)diamine, a series of products consisting of multiple functionalities of primary/secondary amines, phenols, and polyethers were prepared. The curing properties of these products toward diglycidyl ether of bisphenol-A (DGEBA) were examined by a differential scanning calorimeter (DSC). Mechanical properties of the cured polymers were also tested. The important features for these structures and curing properties were noticed: (1) Compared with poly(oxyalkylene)amines, the built-in phenols in the structures of Mannich bases can function as a accelerator for amine curing toward diglycidyl ethers which made Mannich bases exhibit a high curing rate (2) the tailored Mannich structures had a diversity of consecutive amine and phenol curings under catalytic (triphenyl phosphine) or different temperature conditions in a stepwise manner, which affected cured properties accordingly. (3) the polymers cured by the Mannich bases had demonstrated an improved mechanical properties, including tensile and flexural strength, over materials cured by the corresponding poly(oxyalkylene)diamines. The curing profiles and the mechanical properties of the cured polymers can be correlated with the Mannich structural variations. These NP/DCPD adducts mixed with novolak (PF1120) or JeffamineR D-400 amine as co-curing agents, the tricyclodecane structure was introduced into the epoxy network and resulted an improvement of flexibility. The improvement in tensile strength and elongation has been shown by using NP/DCPD derived Mannich amine as curing agents in comparison with poly(oxypropylene) diamine at 400 molecular weight and diethylenetriamine.
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蔡仲銘. "Reaction mechanism of poly(oxyalkylene)amine-derived polymers intercalating montmorillonite." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/26055880450867012264.
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Chu, Chien-Chia, and 朱建嘉. "The Mechanism of Poly(oxyalkylene)amine-Derived Polymers Intercalatind Montmorillonite to Exfoliation." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/62818688945611355501.
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碩士國立中興大學
化學工程學系
91
In this paper, using two kinds of diamines (PO and EO) to polymerize two kinds of polymers. One is Amine-Terminated Mannich Oligomers (AMO), the other is Amine-Terminated BPA Epoxy Oligomers(AEO), and go a step further to use these two polymers to intercalate montmorillonite (MMT). Comparing the mechanism with intercalation and exfoliation, and using XRD to measure MMT’s basal-spacing. In part one, two kinds of wide molecular weight copolymers were prepared from the reaction of poly(oxyalkylene)diamine, p-cresol and formaldehyde. By the acidification of the end group amine of the copolymers, the quarternary amine salt can exchange with the Na+ in the layer silicate galleries. D2000 AMO is hydrophobic can enlarge basal-spacing to 50Å. Furthermore, by controlling the HCl amount addition, the one-step exfoliation will observe by zig-zag conformation. In the other hand, ED2001 AMO is hydrophilic. By treating with different equivalents of hydrochloric acid, and the basal-spacing is still 18Å. In part two, two kinds of wide molecular weight copolymers were prepared from the reaction of poly(oxyalkylene)diamine and epoxy. By the acidification of the end group amine of the copolymers, the quarternary amine salt can exchange with the Na+ in the layer silicate galleries. D2000 AEO is hydrophobic can enlarge basal-spacing to 56Å. In the other hand, ED2001 AEO is hydrophilic. By treating with different equivalents of hydrochloric acid, and the basal-spacing is still 18Å.
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Lin, Shiau Feng, and 林曉峰. "The Properties of Mannich Bases Derived from Poly(oxyalkylene)amines and Phenols." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/43791605205824932529.
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碩士國立中興大學
化學工程學系
88
The Mannich reaction of poly(oxyalkylene)amine, alkyl-phenol, and formaldehyde gives a series of mixing products, namely Mannich Bases. The structures of these adducts were constituted of the poly(oxyalkylene) segments, phenols, and amines which identified by GPC, H1-NMR, amine titration etc. These products were divided into two classes according to the nature of products: one is lipophilic Mannich Bases; the other is hydrophilic Mannich Bases. The lipophilic Mannich Bases are water-insoluble. And, the hydrophilic Mannich Bases consist of poly(oxyethylene)-segments which could associate with water. This renders the Mannich Bases hydrophilic water-soluble, and surface-active. In part one, the lipophilic Mannich Bases were applied on epoxy curing system. The reaction profiles of amine adducts with epoxides were observed in DSC. The results showed that these adducts could lower the reaction temperatures and activation energies. Besides, the cured polymers also had higher Tg, better thermal stability and improved mechanical strength. In part two, the fundamental surfactancy of hydrophilic Mannich Bases is discussed. These novel surfactants lowered the surface tension of water and interfacial tension of water/toluene (or water/n-hexane) to 31 ~ 33 dyne/cm and 5 dyne/cm, respectively. Some adducts of this series also had cloud points as same as the nonionic surfactants. But the cloud point disappeared in acidic environment due to the increased solubility by the formation of quaternary salt. The aggregating behaviors of these surfactant molecules were also observed by light scattering technique (hydrodynamic diameter) and H1-NMR in different solvents.
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Chin, Stacy Lee. "Synthesis and characterization of glucose- and galactose- derived poly-amido-saccharides (PAS)." Thesis, 2017. https://hdl.handle.net/2144/27571.
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Polysaccharides are widely diverse in structure and can vary in molecular weight, sugar composition, monomeric sequence, stereochemistry, glycosidic linkage, branching, and functionalization. Due to these attributes, polysaccharides are highly abundant in nature and are found in a variety of applications across biology, chemistry, medicine, and commercial products. As the structural diversity within carbohydrate polymers is challenging to replicate under synthetic means, these materials are commonly isolated from natural resources, which introduces unwanted variation between batch samples and requires extensive purification to isolate final products. Although enzymatic approaches to obtain polysaccharides have been explored, these routes typically require expensive starting materials and cannot introduce non-natural functional groups. While chemical synthetic routes of polysaccharide structures and polymer-mimics have been reported, it is challenging to have synthetic control over molecular weight, stereochemistry, and linkages while maintaining the high density of similar functional groups and rigid pyranose backbone.
Poly-amido-saccharides (PASs) are enantiopure carbohydrate polymers in which sugar units are joined by 1,2-amide linkages. By using an anionic ring-opening polymerization of β-lactam monomers, PAS structures are synthesized with control over molecular weight, functional groups, batch-to-batch consistency, and at low polydispersity. Importantly, PAS samples are water-soluble and contain the rigid pyranose backbone as found in natural polysaccharides. As PAS structures are not found in nature, the unnatural peptide linkage between monosaccharide units contributes to their unique structural features and chemical properties. The Grinstaff group has reported PASs to have a robust helical secondary structure; minimal cytotoxicity in different mammalian cell lines; ability to be functionalized on the monomer and polymer level; varying water-solubility depending on its sugar composition; and, potential to be recognized as natural carbohydrates (glucose-derived PAS are recognized by lectin concanavalin A similarly to glucose).
Experimental and computational techniques, including circular dichroism, 2D-NMR spectroscopy, and molecular dynamics simulations, were used to explore structure-function relationships between glucose- (glc-) and galactose- (gal-) PAS structures. Cytotoxicity and cellular uptake studies were conducted to investigate their biocompatibility properties. Finally, sulfated glc-PASs structures were explored to possess anticoagulation activity and binding interactions with antithrombin III to serve as heparin-mimics to address current clinical challenges associated with heparin usage.2019-03-17T00:00:00Z
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Hsu, Yen-Chi, and 許彥琦. "Poly(styrene-co-maleic anhydride) derived polymeric dispersants and organic mechanism of Clay." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/33695217349954649856.
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碩士國立中興大學
化學工程學系
93
In this dissertation, a host of dispersants derived by poly(styrene-co-maleic anhydride)(SMA) were prepared. Part 1 By varying the structure parameters of the SMA copolymer and the functions of side chain, the designed dispersants are effective to disperse several kinds of the inorganic particles. Carboxylic sodium salts (-COONa) on the SMA backbone with the ratio of styrene/MA=6/1(SMA6000) which could disperse MgSO4 in toluene phase at 12 wt % and stable for 2 month. SMA2000 grafted on the M2070 as the pendents could decrease the yellow pigments’ particle size (α-FeOOH) from the range of 550-1750 nm to 210 nm and it also effective as the coloring agents (improve the color ability).SMA1000-MPEG is good for wetting the cement particle, which could reduce the water quantity (from 30g/100g to 24g/100g water/cements) for cement mixture. Part 2 A family of comb-like polyamines was synthesized by grafting various polyoxypropylene-amines (POP-amines) on the styrene/maleic anhydride copolymers (SMA) through the amidoacid linkages. The polyamines were found to have a superior surfactancy of lowering the toluene/H2O interfacial tension until 4mN/m at extremely low critical micelle concentration (CEC) of 10-3 w%. By varying the length of amine pendents and the styrene/maleic anhydride backbone ratio, the POP-grafting copolymers enable to intercalate sodium montmorillonite (Na+-MMT) in two different manners. With the ionic exchanging intercalation, the flexible pendants may anchor into silicate interlayer by the multiple quaternary ammonium salt (-NH3+Cl−) tethering groups. The driving force of ionic exchanging rendered the embedding of organic components and also the expansion of silicate gallery from 13 Å to 44 Å. As a result, the hydrophobic backbone of SMA copolymers could generate a corona phase or partially embedding in the gallery. Two types of core-shell structure with the layered silicates as a rigid core reflect their difference in the hydrophilic/hydrophobic balance and hence the interfacial property. Their characterizations in thermal stability, dispersion in toluene and ability of decreasing surface tension are correlated to the core-shell structures.
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Xu, Wei-Hao, and 胥偉豪. "The Optimization Model for Factories Location of Poly Lactic Acid’s Refuse Derived Fuel." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/59629097056618001236.
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碩士東海大學
環境科學與工程學系
104
With the development of industry technology, oil can be replaced by disposable plastic product which made from corn. About 106 tons PLA will be produce in each month, and there are many disadvantage of recycle PLA with compost 、incineration and material recycled. Refuse Derived Fuel is a kind of fuel which made from organic waste with physical process, the renewable fuel start to become an important alternative energy. During this particular research, the RDF will go through the burning process to eliminate the PLA.while the main purpose among the research is to find the best location and optimal scale, with the mathematical programming method and to reach the minimum cost. To accomplish the ultimate goal, the optimal solution will need to use the Lingo 11.0 software to calculate, towards to find the best location PLA should be transported into the factories in record, and to reach the balance between the output of PLA and RDF-5 processing efficiency. In order to investigate the development in the future, which relies on the scenario analysis, to find out the most appropriate location and scale among the various situations.
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Jan, Jun-Zhe, and 簡俊哲. "Selective Synthesis and Properties of Copolymers Derived from Poly(oxyalkylene)amines Cyanuric Chloride." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/59443190914420702547.
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碩士國立中興大學
化學工程學系
89
Abstract The nuclephilic substitution reaction of poly(oxyalkylene)amine and cyanuric chloride (cc) gives a series of derivatives in a selective manner by controlling the reaction temperature. The structures of these derivatives are constituted of the hydrophobic poly(oxypropylene)-segments and hydrophilic poly(oxyethylene)-segments which could interact with water by hydrogen bonding. As a resalt, the cyanuric chloride derivatives was proved to be a polymeric surfactant. First, this study was investigated with respect to the selectivity of cyanuric chloride with Jeffamine® M-2070. By varying the molar ratios of M-2070 and temperature, the suitable reaction conditions of the three avtive sites in cyanuric chloride was found (0oC、25oC、130oC). The structures were determined by GPC. Furthermore, a family of block copolymers with different molecular weights and stuctures were prepared by using the selective reactions of cyanuric chloride and polyetheramines. Their fundamental surfactancy has been discussed. These polymeric surfactants lowered the surface tension of water and interfacial tension of water/toluene (or water/n-hexane) to 29~35 dyne/cm and 2.1 dyne/cm, respectively. Some adducts exhibited cloud points similar to the nonionic surfactants. The higher cloud point temperatures were observed for the higher HLB values.
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LO, MEI-LING, and 羅梅玲. "Micelle Formation in Poly(L-lactide)/Poly(ethylene glycol)/Poly(L-lactide) Block Copolymers and Drug Release from the Microcapsules Derived from Micelles:Experiments and Model Analysis." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/49374255158240496792.
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碩士國立臺灣科技大學
高分子工程系
92
Abstract (Part I ) The PLLA-PEG-PLLA triblock copolymers with fixed PEG length(Mn=4000 g/mol) and various PLLA lengths from 4,600 to 28,000 g/mol were synthesized and their critical micelle concentrations(CMC) in water were determined with fluorescence spectroscopy and pyrene probe in aqueous solutions.The CMC data over 25~45℃were used to evaluate entropy and enthalpy of micellization, and to calculate the Flory-Huggins interaction parameters(χ) between PLLA blocks and water based on Leibler’s theory. With PLLA block length increasing, χ increases, and oppositely the enthalpy of micellization and the entropy of micellization decrease. In contrast to CMC data for MePEG-PLLA diblocks, the looping of PEG blocks in triblocks significantly affects the micellization. The triblocks exhibit the more ordered structure and stronger cohesion in micelles, as the Flory-Huggins parameters increase. Moreover, the micellization thermodynamics show a more significant difference between diblock and triblock copolymers while the hydrophobic block length increases. Abstract (Part II) In this study, we use the experimental data for Clonazepam drug release from PBLG/PEO microcapsules to calculate the drug diffusion coefficient by the Higuchi model. We then discussed the correlation between the hydrophobic block length and the diffusion coefficient. According to calculations, it revealed that, increasing the hydrophobic block length leads to a greater diffusion coefficient. By using the method of dimension analysis to analyze the control variants of the initial diffusion and the final dissolution, we get five π dimensionless groups: 1－F(the amount of the drug released at a certain time instant ), π1( dimensionless release time), π2( the reciprocal of drug partition constant, π3( the dimensionless dissolution time), π4( the maximum release amount when the release time approaches infinity). Higuchi model can deal with the first 3 dimensionless variables. When the experimental dimensionless releasing time (π1) decreases, the exponent of the power relation between the amount of drug released and π1 approaches 1. According to calculations, it revealed that, when the values of π2 are in the same π1 range in the initial stage, the smaller the π2 values, the longer the line within with range, and the release mechanism approaches the constant rate release. However, the Higuchi model is limited to large values of π2; the model predicts the exponent for the power relation between the amount of drug released (1-F) and π1 approaches 0.5 and therefore does not correspond to the calculations of the experimental data. Furthermore, the calculations of the experimental data based on Higuchi model show that the Higuchi model is more suitable for the release kinetics at an intermediate stage. Moreover, when the Higuchi model is used to analyze the experimental data of the amphiphilic block copolymer microcapsule, the value of the diffusion coefficient is unreasonably small in the initial stage. One of the reasons for this is because the hydrophobic drugs are dispersed heterogeneously in the zone between the hydrophobic core and the hydrophilic shell. This leads to the drug release initially from the heterogeneous-region in the microcapsules, that is in contradiction with the homogeneity assumption in Higuchi’s model.
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Chen, Shih-Yu, and 陳世育. "Poly(acrylic)/Rare Earth Elements Composites Hybrid Thin Film Derived From Nanosize Colloidal Silica." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/54050132623113274260.
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碩士明志科技大學
化工與材料工程研究所
95
Usually, powder-like rare-earth compounds are prepared through sintering at high temperature. However, it is difficult to incorporate rare-earth compounds into inorganic or organic matrices to achieve a uniform dispersion at the molecular level. Fortunately, rare-earth complexes with organic ligands have shown good solubility in common organic solvents. The study used radical polymerization to synthesize the precursor of single functional acrylate (Poly(MMAMSMA)) and poly-functional acrylate (Poly(EDMA-TMPTA-MSMA)). After the synthesis, sol-gel method was applied to prepare the hybrid thin film of (PMMA)/SiO2/EuL3•2H2O and (PEDMA/PTMPTA)/SiO2 /EuL3•2H2O. The results of SCMS, TEM, and XPS showed that both SiO2 and EuL3•2H2O were able to disperse in the hybrid thin film without aggregation. The PL spectra showed the unique emission of Eu3+. The addition of SiO2 made the compounds of Eu3+ disperse better and diminished the effect of concentration quenching and obtained the maximum fluorescence intensity. The UV/Vis spectra and n&k analysis showed that the hybrid thin film had good transparency in visible light, and the refractive index was effectively controlled by the different ratio of SiO2 to EuL3•2H2O. The results of SEM and AFM showed that the hybrid thin film which formed from the polyfunctional acrylic/SiO2/EuL3•2H2O had a flatter surface. The TGA and DSC analysis indicated that the temperature of pyrolysis and Tg increased by the contained volume of SiO2. In addition, the residue also showed an increase in the thermal stability. Finally, acrylic polymer/silica hybrid films were prepared by UV-curing. The reaction of each component in the hybrid films were investigated by FTIR and Raman spectroscopy in this study.
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Lee, Chuan-Min, and 李權珉. "Synthesis and Properties of Crosslinkable Low-dielectric characteristic Poly(phenyl oxide) derived from Eugenol." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/278z9z.
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碩士國立中興大學
化學工程學系所
106
This study mainly discusses the modification and synthesis of engineering plastic Poly(phenyl oxide) PPO. Generally, Poly(phenyl oxide) PPO is difficult to process due to high molecular weight during preparation. The PPO used in this article is a low molecular weight PPO derivative (NORYL SA90). SA90 is a difunctional oligomer. This article uses Hexafluorobenzene to introduce the ends of SA90, and hexafluorobenzene has good structure is symmetrical and has low polarity characteristics and excellent electrical characteristics. The bio-based raw material eugenol and Iso Eugenol was functionalized at the end, and then cured by thermal crosslinking. The comparison and analysis of the thermal properties and electrical property of the modified bio-type Poly(phenyl oxide) PPO and the same commercial products OPE-2st
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Poel, Marc te [Verfasser]. "Experimentelle Untersuchungen zur Identität des Endothelium Derived Relaxing Faktor (EDRF) / vorgelegt von Marc te Poel." 2001. http://d-nb.info/963472038/34.
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Li, Jing. "Cell adhesion mediated by surface-conjugated fibronectin- derived peptides on poly(ethylene glycol)- based polymers." 2004. http://www.library.wisc.edu/databases/connect/dissertations.html.
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Hsu, Yu-Hsien, and 徐毓賢. "Synthesis and Properties of Polyimide-Silica Hybrid Derived from Alkoxysilane-Containing Poly(amic acid)s." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/g4q77j.
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碩士中原大學
化學工程研究所
92
In this study, a silane-containing functional molecule, (3,5-diaminobenzamide-n-propyltriethoxylsilane) was synthesized by the acid chloride reaction and used as diamine monomer to condensate with 3,3-4,4-benzophenone tetracarboxylic dianhydride forming poly(amic acid). And then the syntheses of polyimide-silica hybrid materials were carried out via the sol-gel reaction of TEOS precursor in the presence of the thus-prepared polyamic acids. The morphology, microstructure and the particle sizes and their distribution of silica in hybrid materials was examined by SEM and AFM. The results showed that the SiO2 nanoparticles were evenly distributed inside the hybrid thin films and the silica particle size increased as the silica content increased. The AFM study demonstrated that the thin hybrid films have excellent planarity. The thermal properties of these hybrid materials were measured by TGA, DSC, and TMA. The thermal decomposition temperatures (Td) of hybrid thin films are all above 430℃. The thin hybrid films of BTDA-PDA/silica are more thermal stable than the films of BTDA-PDA/PTSDA/silica owing to the higher molecular weight. The glass transition temperature (Tg) in BTDA-PDA/PTSDA series is higher than BTDA-PDA series because of the coupling effect between polymer chains. Moreover, the results also showed that the glass transition temperature (Tg) increased slightly by decreasing the size of silica particle. Besides, the dielectric constant of hybrid thin films was increased by coupling as well as sol-gel effect and the increase of the silica content. However, the decrease of the silica particle size did not result in a significant effect on the dielectric constant. The coefficient of thermal expansion decreased as the inorganic content increased. Moreover, the coefficient of thermal expansion in BTDA-PDA/PTSDA series was lower than BTDA-PDA series owing to coupling effect. The transparency of the hybrid by UV/vis spectra is also included in this study. In addition, we designed and synthesized a novel diamine, diaminophenyldiethoxysilane, which contains more aromatic groups and symmetrical structure. Therefore, it is expected that the PI/silica hybrid film derived from this monomer will exhibit higher thermal stability and mechanical properties. Consequently, they could have good opportunities to be used in microelectronic process.
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Huang, Ting-Kai, and 黃亭凱. "Modification of Montmorillonite by Using Poly(oxyalkylene)amines and the Applications of the Derived Nanocomposites." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/27955679478651011386.
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博士國立臺灣大學
高分子科學與工程學研究所
101
Poly(oxyalkylene)-amines (POA-amine) are used for affecting sodium montmorillonite (Na+-MMT) in protic mediums. In water, the hydrophobic aggregation of poly(oxypropylene)-rich (POP-) amines in the silicate galleries expands the interlayer spacing up to 10 nm and to exfoliation with over 5 amine equivalents, where as hydrophilic poly(oxyethylene)-rich (POE-) amines could only achieve in a low interlayer spacing of 1.8 nm. On the other hand, all POA-amines in isopropanol (IPA) afford the exfoliation with over 3 amine equivalents. The unexpected exfoliation is explained by the thermodynamic formations of an imaginary membrane surrounding the clay units, followed by amine diffusion from the solvent into the clay galleries. The POA-amine-modification of Na+-MMT in IPA opened a gateway to the preparation of randomized organoclays which in general were not easily achieved by conventional methods. This new finding allowed the exploration of new exfoliating agents embedding particular functionalities for special applications, such as hexachlorophosphazenes (HCP) for enhancing the thermal properties of common polymers. The amine substitution of HCP with POA monoamines (M-amine) afforded aminophosphazenes (AP) at molecular level. Na+-MMT was modified by using HCl-treated AP to prepare AP-exfoliated MMT clay (AP/EMMT) nanohybrids. When the nanohybrid was blended into polyurethane (PU), the presence of silicate platelets promoted the PU stability and retarded the degradation for more than 60 oC under the standard TGA measurement. The co-existence of AP and EMMT at various wt ratios demonstrated a synergistic effect on the improvements of thermal stability as well as the UV resistance under the standard test of UV exposure in wavelength range of 365 to 400 nm. The molecular-level dispersion of AP and silicate platelets had synergistically contributed to the PU thermal and UV stability.