Bien que thermodynamiquement et cinétiquement stable, le dioxyde de carbone est une molécule qui peut être convertie en carbonates cycliques à cinq ou six atomes respectivement au départ d’époxydes ou d’oxétanes moyennant l’utilisation d’un catalyseur approprié. Ces carbonates cycliques sont utilisés comme solvants verts, électrolytes pour les batteries au lithium ou comme intermédiaires pour la synthèse de polymères. Cependant, les performances catalytiques doivent être améliorées en particulier pour lecouplage du CO2 avec les huiles végétales époxydées ou les oxétanes. Dans ce contexte, nous avons développé un nouveau catalyseur homogène bicomposant organique composé d’un sel d’ammonium jouant le rôle de catalyseur et d’un co-catalyseur fluoré simple ou double donneur de liaison hydrogène. Dans un premier temps, l’efficacité de ces nouveaux catalyseurs a été évaluée et optimisée pour le couplage entre un époxyde terminal et le CO2 via des études cinétiques par spectroscopie FTIR ou Raman in-situ sous pression. Ces études ont démontré que l’utilisation combinée de sels d’ammonium et d’alcools fluorés induit un effet synergique permettant la fixation rapide et sélective du CO2 sur les époxydes modèles et les huiles végétales époxydées dans des conditions douces et sans solvant. L’utilisation de cette plateforme catalytique performante a ensuite été exploitée pour la synthèse d’oligocarbonates hydroxyles téléchéliques au départ d’oxétanes nettement moins réactifs que les époxydes. Ces oligocarbonates ont finalement été valorisés pour la synthèse de polyuréthanes CO2-sourcés par extension de chaines en présence de diisocyanates. En complément de ces travaux, une compréhension fine des mécanismes réactionnels a été réalisée via calculs DFT qui ont mis en évidence que l’efficacité catalytique de ces catalyseurs était liée à la stabilisation multiple des intermédiaires et états de transition par liaisons hydrogènes. A ce jour, via une étude comparative, nous avons mis en évidence que ce système catalytique bicomposant constitue un des catalyseurs organiques les plus performants pour le couplage du CO2 et d’époxydes et le seul système organique permettant la conversion d’oxétanes en synthons d’intérêt. / Although it is a thermodynamically and kinetically stable molecule, carbon dioxide can beconverted into five- and six-membered cyclic carbonates by coupling with epoxides or oxetanes, respectively, using appropriate catalysts. Cyclic carbonates are used as green solvents, electrolytes for Liion batteries or intermediates for the synthesis of polymers. However, the catalytic performance must be further enhanced in particular for the coupling of CO2 with epoxidized vegetable oils or oxetanes. In this context, we developed a new highly efficient bicomponent homogeneous organocatalyst composed of anammonium salt as the catalyst and fluorinated single or double hydrogen bond donors as co-catalysts. First,a screening of onium-based catalysts and hydrogen-bond donors was performed. Performances of thecatalysts and optimization of the reaction was realized through detailed kinetics studies using in-situ FTIR/Raman spectroscopy under pressure. We demonstrated that fluorinated alcohols showed unexpected co-catalytic activity due to synergisms between the onium salt and fluorinated co-catalysts enabling the fast and selective addition of CO2 on to model epoxides and epoxidized vegetable oils under solvent-free and mild experimental conditions. The use of this powerful dual catalyst was then extended to the first organocatalytic coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonates that were used asprecursor of CO2-based polyurethanes by chain-extension with a diisocyanate. In addition, a fine comprehension of the mechanisms was investigated by DFT calculations highlighting that the co-catalytic performance of the onium salt/fluorinated alcohol binary catalyst arose from the strong stabilization of the intermediates and transitions states by hydrogen-bonding. To date, through comparative studies, we evidenced that this new catalyst is one

Polímeros dopados com complexos de terras raras são materiais vantajosos na produção de filmes para várias aplicações no campo da luminescência. Neste estudo de polímeros luminescentes obtidos a partir de polímeros como o policarbonato (PC) e o poli(9-vinilcarbazol) (PVK), os filmes dopados com o complexo diaquatris (tenoiltrifluoroacetonato) de európio (III) [Eu(tta)3(H2O)2] foram preparados e suas propriedades térmicas e luminescentes no estado sólido relatadas. O comportamento térmico foi investigado por uso de calorimetria diferencial exploratória (DSC) e análise termogravimétrica (TGA). Devido à adição de complexo terras raras [Eu(tta)3(H2O)2] na matriz de PC e PVK, foram observadas alterações no comportamento térmico, relativo à transição vítrea e estabilidade térmica. As emissões finas características do íon Eu3+ decorrentes das transições 5DO → 7FJ (J = 0-4) indicaram a incorporação de íons de Eu3+ nos polímeros. Os filmes mostraram que a intensidade de emissão luminescente aumenta com o aumento da concentração de terras raras na matriz polimérica acompanhado por uma diminuição na estabilidade térmica. / Polymers doped with rare earth complexes are advantaged in film production for many applications in the luminescent field. In this study luminescent polymer obtained from polycarbonate (PC) and poly (9-vinylcarbazole) films doped with diaquatris (thenoyltrifluoroacetonate) europium (III) complex [Eu(tta)3(H2O)2] were prepared and their calorimetric and luminescent properties in the solid state are reported. The thermal behavior was investigated by differential scannig calorimetry (DSC) and thermogravimetry analysis (TGA). Due of the addition of rare earth [Eu(tta)3(H2O)2] into PC and PVK matrices, changes were observed in the thermal behavior concerning the glass transition and thermal stability. Characteristic broadened narrow bands arising from de 5DO → 7FJ transitions (J = 0-4) of Eu3+ ion indicate the incorporation of the Eu3+ ions into those polymers. The luminescent films show enhancement emission intensity with an increase in the rare earth concentration in polymeric matrix accompanied by decrease in thermal stability.

Studies concerning the formation of industrially useful polycarbonates are the focus of this dissertation. Of particular importance is the biodegradable polymer, poly(trimethylene carbonate) which has a wide range of medical applications. The production of polycarbonates can be achieved by the ring-opening polymerization of cyclic carbonate, or the copolymerization of carbon dioxide and oxiranes or oxetanes. For the production of polycarbonates from these monomers, Schiff base metal complexes have been designed, synthesized, and optimized as catalysts. Detailed kinetic and mechanistic studies have been performed for the ring-opening polymerization of cyclic carbonates, as well as the copolymerization of carbon dioxide and oxiranes or oxetane. In addition, the copolymerization of cyclic carbonates and cyclic esters to modify the mechanical and biodegradable properties of materials used for medical devices has been studied using biocompatible metal complexes. In the process for ring-opening polymerizations of trimethylene carbonate or lactides, Schiff base metal complexes (metal = Ca(II), Mg(II) and Zn(II)) have been shown to be very effective catalysts to produce high molecular weight polymers with narrow polydispersities. Kinetic studies demonstrated the polymerization reactions to proceed via a mechanism first order in [monomer], [catalyst], and [cocatalyst] if an external cocatalyst is applied, and to involve ring-opening by way of acyl-oxygen bond cleavage. The activation parameters (ΔH≠, ΔS≠ and ΔG≠) were determined for ringopening polymerization of trimethylene carbonate, ring-opening polymerization of lactides, and copolymerization of trimethylene carbonate and lactide. In the process for copolymerization of carbon dioxide and oxetane, metal salen derivatives of Cr(III) and Al(III) along with cocatalyst such as n-Bu4NX or PPNX (PPN = bis(triphenylphosphine)iminium, and X = Br, Cl and N3) have been shown to be effective catalysts to provide poly(trimethylene carbonate) with only trace amount of ether linkages. The formation of copolymer is proposed not to proceed via the intermediacy of trimethylene carbonate, which was observed as a minor product of the coupling reaction. To support this conclusion, ring-opening polymerization of trimethylene carbonate has been performed and kinetic parameters have been compared with those from the copolymerization of carbon dioxide and oxetane.

Made available in DSpace on 2014-10-09T12:54:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:20Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP

Made available in DSpace on 2014-10-09T12:54:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:20Z (GMT). No. of bitstreams: 0 / O polímero Durolon foi caracterizado para ser utilizado como um detector de traços nucleares de estado sólido. Nestes detectores, o testemunho da passagem da radiação é um dano na estrutura molecular do polímero que após ser atacado em uma solução química se transforma em um traço, permanente e visível em um microscópio ótico. A caracterização do Durolon foi feita mediante estudos do diâmetro do traço, da eficiência de produção de traços, da transmissão de luz pelo polímero e do ângulo crítico de incidência da partícula em sua superfície, visando fornecer os subsídios necessários para interpretar as informações registradas. No presente trabalho os danos no polímero foram causados por partículas - da reação nuclear 10B(n,)7Li, mediante a irradiação de uma tela de boro em um feixe de nêutrons térmicos, oriundo de um equipamento instalado no canal 08 do reator nuclear de pesquisas IEA-R1 do Instituto de Pesquisas Energéticas e Nucleares IPEN-CNEN/SP. Estes estudos foram realizados mediante o emprego de um sistema digital que foi desenvolvido neste trabalho. A sua utilização permitiu uma maior qualidade e eficácia quanto a aquisição e a análise de dados bem como acesso a diversos outros parâmetros referentes aos traços, até então inacessíveis pelo sistema analógico que estava em uso no IPEN e, assim, acesso a teoria da formação da imagem nestes detectores. As características determinadas para o Durolon foram comparadas com as obtidas para outros dois detectores de traços nucleares, o Makrofol-E e o Makrofol-DE e, demonstram a viabilidade de sua utilização. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP

Polímeros dopados com complexos de terras raras são materiais vantajosos na produção de filmes para várias aplicações no campo da luminescência. Neste estudo de polímeros luminescentes obtidos a partir de polímeros como o policarbonato (PC) e o poli(9-vinilcarbazol) (PVK), os filmes dopados com o complexo diaquatris (tenoiltrifluoroacetonato) de európio (III) [Eu(tta)3(H2O)2] foram preparados e suas propriedades térmicas e luminescentes no estado sólido relatadas. O comportamento térmico foi investigado por uso de calorimetria diferencial exploratória (DSC) e análise termogravimétrica (TGA). Devido à adição de complexo terras raras [Eu(tta)3(H2O)2] na matriz de PC e PVK, foram observadas alterações no comportamento térmico, relativo à transição vítrea e estabilidade térmica. As emissões finas características do íon Eu3+ decorrentes das transições 5DO → 7FJ (J = 0-4) indicaram a incorporação de íons de Eu3+ nos polímeros. Os filmes mostraram que a intensidade de emissão luminescente aumenta com o aumento da concentração de terras raras na matriz polimérica acompanhado por uma diminuição na estabilidade térmica. / Polymers doped with rare earth complexes are advantaged in film production for many applications in the luminescent field. In this study luminescent polymer obtained from polycarbonate (PC) and poly (9-vinylcarbazole) films doped with diaquatris (thenoyltrifluoroacetonate) europium (III) complex [Eu(tta)3(H2O)2] were prepared and their calorimetric and luminescent properties in the solid state are reported. The thermal behavior was investigated by differential scannig calorimetry (DSC) and thermogravimetry analysis (TGA). Due of the addition of rare earth [Eu(tta)3(H2O)2] into PC and PVK matrices, changes were observed in the thermal behavior concerning the glass transition and thermal stability. Characteristic broadened narrow bands arising from de 5DO → 7FJ transitions (J = 0-4) of Eu3+ ion indicate the incorporation of the Eu3+ ions into those polymers. The luminescent films show enhancement emission intensity with an increase in the rare earth concentration in polymeric matrix accompanied by decrease in thermal stability.

The present work describes a selection of strategies for the synthesis of functional aliphatic polycarbonates. Using an end-group functionalization strategy, a series of DNA-binding cationic poly(trimethylene carbonate)s was synthesized for application as vectors for non-viral gene delivery. As the end-group functionality was identical in all polymers, the differences observed in DNA binding and in vitro transfection studies were directly related to the length of the hydrophobic poly(trimethylene carbonate) backbone and the number of functional end-groups. This enabled the use of this polymer system to explore the effects of structural elements on the gene delivery ability of cationic polymers, revealing striking differences between different materials, related to functionality and cationic charge density. In an effort to achieve more flexibility in the synthesis of functional polymers, polycarbonates were synthesized in which the functionalities were distributed along the polymer backbone. Through polymerization of a series of alkyl halide-functional six-membered cyclic carbonates, semicrystalline chloro- and bromo-functional homopolycarbonates were obtained. The tendency of the materials to form crystallites was related to the presence of alkyl as well as halide functionalities and ranged from polymers that crystallized from the melt to materials that only crystallized on precipitation from a solution. Semicrystallinity was also observed for random 1:1 copolymers of some of the monomers with trimethylene carbonate, suggesting a remarkable ability of repeating units originating from these monomers to form crystallites. For the further synthesis of functional monomers and polymers, azide-functional cyclic carbonates were synthesized from the bromo-functional monomers. These were used as starting materials for the click synthesis of triazole-functional cyclic carbonate monomers through Cu(I)-catalyzed azide–alkyne cycloaddition. The click chemistry strategy proved to be a viable route to obtain structurally diverse monomers starting from a few azide-functional precursors. This paves the way for facile synthesis of a wide range of novel functional cyclic carbonate monomers and polycarbonates, limited only by the availability of suitable functional alkynes.

Hybrid polymer laminates of polycarbonate and PMMA have generated considerable interest among researchers as an alternative to traditional glass armours because of their potential for reduced cost and weight. Generally, the development of ballistic armour is carried out experimentally which is an expensive task in terms of time and cost. Numerical simulation provides a much greater facility to understand the phenomenon of ballistic impact and the effects of various parameters on the response to such impact. In addition it provides an easy means of comparing the impact performance of different materials as well as combination of materials forming hybrid laminates. The aim of this research was to develop a numerical modelling capability to simulate the ballistic response of hybrid polymer laminates, specifically polycarbonate and PMMA, using a commercially available finite element code LS-DYNA. The challenge was to work within the limitations of the material models and the failure algorithms available within LS-DYNA, and still try to reproduce the behaviour observed experimentally by previous researchers, initially on monolithic plates of polycarbonate and PMMA and then on hybrid laminates. The first part of the study focuses on a detailed literature survey on mechanical and dynamic characterisation of polycarbonate and PMMA as well as experimental and numerical studies previously conducted on ballistic behaviour of these materials as well as their combinations. The material properties of the polymers compiled from this literature survey were used as input for the selected LS-DYNA material model. Impact simulations were carried on monolithic and laminated media of polycarbonate and PMMA and where possible these were compared to experimental results. It was observed that the results agreed with the experimental data qualitatively. Quantitatively the results showed some discrepancies which were attributed to the limitations faced in simulating the exact test conditions numerically. Numerical simulations were carried out to study the effects of variations in laminate thickness and plate support diameters as well as to examine the influence of the bond between the layers. Finally the impact response of four different combinations of polycarbonate and PMMA are compared to each other for different laminate thicknesses.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T17:38:38Z No. of bitstreams: 0 / Made available in DSpace on 2016-11-11T17:38:38Z (GMT). No. of bitstreams: 0 / O polímero de policaprolactona (PCL) dopado com [Eu (TTA) 3 (H2O) 2] no complexo 1, 2, 5, 10 e 15% de concentrações foram preparadas e as suas propriedades térmicas e de luminescência discutidas. As bandas de absorção de infravermelho no intervalo de 1800-1550 cm-1 correspondente ao ν sensível (C = O) foram seleccionados para a técnica de ajuste de curva de desconvolução e confirmou-se que os picos de componentes são deslocados gradualmente com o aumento da concentração de dopagem. O deslocamento do ν (C = O) banda para os β-dicetonato complexos para novas posições nos sistemas dopados (pCLE) proporcionam boa evidência de que o ião de metal está coordenado aos átomos de oxigénio dos grupos carbonilo PCL. Calorimetria exploratória diferencial (DSC) não mostraram alterações significativas na segunda temperatura de fusão (Tm2) para as amostras de cinema. No entanto, a cristalinidade é afectada pelo complexo dopante em materiais de polímero em maior concentração. A análise termogravimétrica (TGA) não mostra nenhuma perda de peso na gama de 50-200 ° C para os sistemas poliméricos dopados, corroborando a interacção da matriz de polímero com Eu3 + complexo n por substituição das moléculas de água no complexo precursor. A observação das bandas de emissão característicos resultantes das transições 5D0 → 7FJ (J = 0-4) dominadas pela hipersensibilidade transição 5D0 → 7F2 em torno de 614 nm, de íon Eu3 +, indicando que a incorporação de Eu3 + complexo no sistema de polímero. O valor da eficiência quântica de emissão de nível 5D0 para os materiais poliméricos dopados (η = 40-62%) são mais elevados do que para o complexo [Eu (TTA) 3 (H2O) 2] complexo (η = 29%), sugerindo que o matriz de polímero actua como co-sensibilizador do processo de luminescência. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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