Tesis sobre el tema "Polymères à base d'acrylamide"
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Miguel-Arricau, Sophie. "Corrélation structure/propriété de polymères à base d'acrylamide pour des applications en récupération assistée des hydrocarbures (RAH)". Electronic Thesis or Diss., Pau, 2022. https://theses.hal.science/tel-04010751.
Texto completoThe knowledge of the physico-chemical properties of polymer solutions for enhanced oil recovery (EOR) is crucial to optimize the process. The purpose of this work was to consolidate and complete an universal viscosity model depending on C[η] parameter. The later allows taking into account the degree of interpenetration of polymer chains (critical concentration, C*, diluted and semi-diluted solutions). Various polymer parameters have been studied as the effects of microstructures, polymer size (molar mass and dispersity) as well as chemical composition. A library of polymer models was elaborated by controlled radical polymerization (RADT/MADIX). Series of polyacrylamides, statistical and asymmetric copolymers of acrylamide-sodium acrylate and post-hydrolyzed polyacrylamides were synthesized and characterized by steric exclusion chromatography and capillary rheology and the analytical protocols and techniques were optimized. The effects of the microstructure onto dimensional, rheological and complexation physico-chemical properties were determined
BOULAHIA, JALEL-EDDINE. "Synthese et caracterisation de copolymeres a base d'acrylamide porteur de chaines peptidiques : leur utilisation en catalyse asymetrique". Paris 6, 1988. http://www.theses.fr/1988PA066644.
Texto completoSemaan, Chantal. "Polymères nanostructurés à base de nanotubes de carbone". Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14187/document.
Texto completoThis work is concerned with the study of carbon nanotubes (CNT) dispersions in a polymer matrix in order to obtain nanocomposite with unique properties. In the first part, we investigated the CNT wrapping by amphiphilic block copolymers to facilitate their suspension in aqueous solution. Based on the results, we could assess the effect on CNT dispersion quality of the molar mass of copolymers, the nature of the hydrophobic block and the length of hydrophilic block. In the second part, the incorporation of CNTs in polymer matrix was developed. Water or melt processing were chosen to control the distribution of CNTs in various polymer matrices (Polyethylene oxide, polyethylene and polymethyl methacrylate) through a prior wrapping of CNT. The studies of physical properties, including rheological and electrical properties, of nanocomposites were undertaken. Relationships between the state of dispersion, the nature of the coating and the method of preparation of composites were established
Antoun, Tarek. "Synthèse et caractérisation de nanomatériaux hybrides à base d'olygothiophènes". Paris 7, 2008. http://www.theses.fr/2008PA077115.
Texto completoThis dissertation focuses on the development of new approaches for elaboration of hybrid materials based on oligothiophenes. The first part of this work reports a one-pot method for preparing cds nanoparticles (nps) bound to oligothiophenes. Tem and x-ray diffraction show that the cds-oligothiophenes are monodisperse. The amount of oligothiophene and the nature of surface binding have been studied in detail using xps, ir, uv-visible and fluorescence spectroscopy. The major advantage of this method is that we use functionalized π-conjugated electroactive systems as ligands to control np growth. The electroactive ligand binds to the np surface and allows intimate contact between the np and the conjugated backbone, leading to better electronic communication between the two components. In the second part of this manuscript we describe the development of a new method for elaborating rod-coil polymers. The raft polymerization of mma and styrene with three different chain transfer agents, generated from oligothiophene dicarboxylate, yields polymers with narrow molecular weight distributions. Uv-visible, nmr and maldi-tof were used to confirm the presence of the expected raft agent end-groups. Attempts were made to initiate controlled radical polymerization from the surface of a cds nanoparticle modified with oligothiophenes. The last chapter reports the crystal structures of a series of mof containing oligothiophene dicarboxylate linkers. The influence of the angle of the rigid oligothiophene core is exemplified in the crystal structure of (mop-28) obtained by linking the square planar cu₂(coo)₄ paddle-wheel units with the flexible 2,2':5',2"-terthiophene-5,5"-dicarboxylate
Jhurry, Dhanjay. "Synthèse et caractérisation de polymères à base de saccharose". Bordeaux 1, 1992. http://www.theses.fr/1992BOR10528.
Texto completoLaflèche, Fabrice. "Systèmes associatifs à base de POE linéaire et en étoile : caractérisation et modélisation". Le Mans, 2002. http://cyberdoc.univ-lemans.fr/theses/2002/2002LEMA1010.pdf.
Texto completoThis work deals with the study in aqueous solutions of mixtures of hydrophobically end-capped linear polyethylene oxide (PEO) on one (monofunctional) or two (difunctional) ends. Spherical micellar structures are formed by these mixtures with agregation degrees which do not depend on the fraction of difunctional PEO. Difunctional PEO allows reversible bridging between the micelles. The system is a good model for understanding the reversible agregation by varying inter-micellar attractivity. The phase diagram and the micellar association can be described and modelized by considering micelles as sticky hard spheres with attractive strength depending on the fraction of disfunctional PEO and temperature. At high concentration, a so-called hard gel of close packed micelles is formed. Static and dynamic light scattering, fluorescence and rheology have been used to investigate these systems. Anionic polymerisation has been used to synthetize hydrophobically end-capped star PEO in order to understand the influence of the architecture on the dynamics and the phase diagram of such associative systems. Hydrophilic-lipophilic balance has been changed by varying the alkyl length in order to study its influence on the associative behaviour
Koutsouras, Dimitrios. "Dispositifs à base de Polymères Conducteurs pour l’Électrophysiologie in vitro". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEM017/document.
Texto completoBioelectronics is an emerging field that is aiming to combine the worlds of biology and electronics. Among all the other materials, organics present a unique set of features that renders them ideal candidates for this new field. Their soft nature gives better mechanical stability, while the fact that they can conduct both electrically and ionically makes them ideal candidates to bridge the gap between electronic devices and living tissue. In addition they provide oxide free interfaces that could interact more efficiently with biology and allow chemically modification that increase biological functionality. These ideas, together with the organic devices fabrication approaches are presented in Chapter 1.Electrodes are the main experimental tool for electrophysiology and this is why Chapter 2 presents the main physics principle behind them. Chapters 3 and 4 implement the knowledge obtained from the electrode modeling to real biological measurements. Chapter 3 presents activity recordings from Hippocampal cell cultures and Chapter 4 form pancreatic cells. Chapter 5 introduces us to a different device as it presents the Organic electrochemical transistor (OECT) and presents a read out circuit board that could facilitate OECT electrophysiological recordings. Chapter 6 closes this thesis with an application of OECT on astrocyte recordings
Gritti, Fabrice. "Etude de phases stationnaires à base de polymères cristaux liquides". Bordeaux 1, 2001. http://www.theses.fr/2001BOR12397.
Texto completoZarrouki, Arthur. "Synthèse de polymères à base d'éthylène pour additiver les carburants". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1039.
Texto completoThe additivation of diesel fuels allows operating engines at low temperatures without filter blocking and thus fulfilling legal requirements. Ethylene based copolymers such as ethylene-vinyl acetate copolymers, made by free radical polymerization at high pressure (above 2000 bars) and high temperature (above 200 °C) are frequently used as middle distillate cold flow improvers (MDFI). A new free radical copolymerization process of ethylene and vinyl acetate in organic solvent media has been developed. This process gives access to polymers close to commercial MDFI additives under tremendous less drastic conditions (under 250 bars of ethylene and 70 °C). Thanks to this process, a wide diversity (variation of the nature of the polar unit, of polymer architecture…) of ethylene based polymers was obtained. Moreover, EVA model copolymers have been synthesized by metathesis. Thanks to these numerous and diverse ethylene based polymers combined with thermal analysis and X-ray scattering studies a better understanding of the operating mode of these additives in a diesel fuel has been achieved. The structural characteristics of the polymers enabling their effectiveness as diesel fuel cold flow improvers have also been established
Rynkowska, Edyta. "Matériaux innovants à base de polymères et de liquides ioniques". Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR012/document.
Texto completoIn the last decades, membrane separation has played an important role in many industrial processes thanks to its versatility, low energy consumption, high performances of membranes, as well as a possibility of combining membrane technologies with other separation processes. Membrane technologies gave a great contribution to the improvement of separation processes in the industrial scale thanks to a number of advantages, such as the high selectivity of the separation, the opportunity to work with thermolabile compounds, and low energy demand. Pervaporation process is an important membrane separation technique used to separate binary or multicomponent liquid mixtures including close boiling solvents, azeotrope mixtures, and isomers. During pervaporation, feed components are in the direct contact with one side of the lyophilic membrane, while the selected components are preferentially transported across the membrane to the permeate side. Membranes used in pervaporation must be characterized by high selectivity, chemical stability, and mechanical strength at high temperatures. Selectivity and transport properties of the membrane determine the overall efficiency of the separation process. The comprehensive characterization of membranes is the crucial approach and can lead to broaden the knowledge about the influence of the membrane structure and membrane preparation conditions on the equilibrium, separation, and transport characteristics of the studied membranes, in order to develop new polymer materials with the expected efficiency of the separation process. Research has been also focused on the development of the membranes filled with ILs in order to tailor the separation properties of the developed membranes used in liquid separation by pervaporation, gas separation, and separation of metal ions as well as the conducting barriers in fuel cells. ILs are characterized by good thermal stability, high ionic conductivity, negligible vapor pressure, and low melting point. Due to their numerous unique properties, polymer membranes containing ILs (polymer-ILs) possess wide range of advantages, like better separation properties than the classical polymer membranes. This fact is related with much higher molecular diffusion in ionic liquid than in polymers. Therefore, the use of polymer-ILs in separation processes would result in superior separation behavior and higher fluxes. Morphology and physicochemical properties of ILs can be “tailored” depending on the separated system in order to obtain a suitable polymer material for a given separation process without preparation of a chemically new membrane. Even though there is a growing interest in the application of polymer membranes filled with ILs, the polymer-ILs based separation processes are limited due to the losses of the unbound ionic liquid in the course of the exploitation. The PhD is realized in the frame of "co-tutelle" system between the Faculty of Chemistry at the Nicolaus Copernicus University (NCU) in Toruń, Poland (Membranes and Membrane Separation Processes Research Group) and the University of Rouen Normandy, France (Barrier Polymer Materials and Membranes (MPBM) Research Group of the Laboratory of Polymers, Biopolymers, Surfaces (PBS)). The main aim of the present PhD thesis is to elaborate novel dense membranes based on poly(vinyl alcohol) (PVA) and cellulose acetate propionate (CAP) filled with various reactive and polymerizable ILs in order to obtain the polymer-ionic liquid system in which ionic liquids are linked inside the polymer structure. The investigation of physicochemical characteristics and study of the equilibrium, barrier, and transport properties of the obtained membranes was carried out. Furthermore, the selected membranes were tested in pervaporation process in contact with water-propan-2-ol mixture, water and gas permeation measurements
Fusteș-Dămoc, Iolanda. "Matériaux polymères durables synthétisés à base d'oligo- et de polysaccharides". Electronic Thesis or Diss., Université Côte d'Azur, 2023. http://www.theses.fr/2023COAZ4076.
Texto completoThe durability of materials is their ability to withstand over time the influence of various factors such as temperature, humidity and breakage while maintaining their characteristics.Durable polymer materials are the solution to environmental pollution. In this context, the development of sustainable polymer materials based on biodegradable compounds, which are abundant in nature, even from industrial waste, and which also have a low cost price, is a possible alternative to materials based on fossil compounds, which are toxic. At the same time, the use of minimal chemicals is an advantage for large-scale production by industries. In addition, obtaining advantageous properties under these conditions, tailored to certain types of applications, brings added value, which recommends their use over toxic materials.Oligo- and polysaccharides represent a suitable raw material that could be exploited in the design of durable polymeric materials. Their use has already aroused real interest among researchers, but their industrial application faces a number of difficulties: from inadequate technological processes and high consumption of solvents and chemicals to the high costs of obtaining, recycling and reusing materials, in line with a circular economy, which is essential in addressing environmental protection. This circular economy is about extending the life cycle of materials by reducing waste. by promoting the repair, reuse and recycling of materials for as long as possible. This PhD thesis presents the results obtained from the synthesis, characterisation and testing of sustainable oligo- and polysaccharide-based materials.The overall objective of the PhD thesis is to develop durable materials that incorporate and exploit non-toxic, renewable, environmentally friendly, cheap and naturally abundant compounds such as oligo- and polysaccharides in a circular economy.The main research directions developed in the thesis are:- Valorisation of β-cyclodextrin, from the oligosaccharide category, and chitosan, from the polysaccharide category, in sustainable material systems;- Development of such sustainable materials using a minimum number of steps and a reduced number of compounds and solvents;- The use, in particular, of chitosan in solid (powder) form to optimise the mechanical and thermal properties of the systems;- Achieving improved mechanical and thermal properties of the materials by introducing oligo- and polysaccharides, compared to reference systems, for chitosan-based systems, and for β-cyclodextrin-based systems: optimised adsorption of various pollutants such as antibiotics, organic dyes, heavy metals;- increased application potential of materials in various fields such as biomedical, food packaging, epoxy coatings, aerospace, due to the advantages of oligo- and polysaccharides;- Testing the recyclability of β-cyclodextrin-based nanomaterials to improve material durability
Pembouong, Gaëlle. "Caractérisation de polymères supramoléculaires hiérarchiques à base de cyclodextrines fonctionnalisées". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS005/document.
Texto completoMolecular systems with nanometer-sized dimensions are involved in a wide variety of processes and biological functions. Understanding the mechanisms controlling their multi-lengthscale structure presents a major interest. For instance, despite this challenge, there is so far no reliable synthetic system forming well-defined tunable fibrillar objects with a monodisperse diameter in aqueous solution. The aim of this work is to develop a tool box of di-functionalized cyclodextrins (CDs) specifically designed to self-assemble into supramolecular rods that could then reach higher levels of hierarchy via interactions mediated by the secondary functionalization. The study of the first level of association of these compounds by viscosimetry, ITC and SANS showed that the use of bridged CDs allows the polymerization by suppressing the self-inclusion phenomenon. As a result, we developed two tunable cationic supramolecular polymers (SMP) based on functionalized β-CD with relatively high polymerization degrees. Their ability to form hierarchical SMP with rigid polyanionic species was then assessed by DLS, spectroscopy and cryo-TEM. In optimized concentration and charge ratio conditions, three different water-soluble hierarchical assemblies were formed. We showed that the first level of association and the high directionality of the secondary interactions are key parameters to achieve these stable, well-defined, hierarchical assemblies. These tunable structures will be therefore used as a platform to get greater insight into hierarchical assembling processes
Agnaou, Reda. "Polymères supramoléculaires semi-cristallins à base de Polyamides et PMMA". Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066544/document.
Texto completoDesign of materials with polymer-like properties at service temperature but able to flow like simple liquids when heated remains one of the important challenges of supramolecular chemistry. Combining these antagonistic properties is highly desirable to provide durability, processability, and recyclability of materials. Here, we explore a new strategy based on polycondensation reactions to design supramolecular polymer materials with stress at break above 10 MPa and melt viscosity lower than 1 Pa·s. We describe the synthesis and rheological and mechanical properties (uniaxial tensile tests) of supramolecular polymers based on a multiblock polyamide architecture. The flexibility of polycondensation reactions made it possible to control the molecular size distribution, the strength of hydrogen bonds, and the crystallization of middle and end groups and to achieve targeted properties. A second family of supramolecular polymers, based on a PMMA backbone, was designed and synthesized by ATRP or RAFT polymerization. Controlled radical polymerization enabled precise control over molecular weight and chemical modification of the oligomers allowed us to obtain supramolecular PMMA terminated at both ends by associative groups. Thermal, mechanical and rheological properties of this supramolecular polymer are described
Pembouong, Gaëlle. "Caractérisation de polymères supramoléculaires hiérarchiques à base de cyclodextrines fonctionnalisées". Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS005.
Texto completoMolecular systems with nanometer-sized dimensions are involved in a wide variety of processes and biological functions. Understanding the mechanisms controlling their multi-lengthscale structure presents a major interest. For instance, despite this challenge, there is so far no reliable synthetic system forming well-defined tunable fibrillar objects with a monodisperse diameter in aqueous solution. The aim of this work is to develop a tool box of di-functionalized cyclodextrins (CDs) specifically designed to self-assemble into supramolecular rods that could then reach higher levels of hierarchy via interactions mediated by the secondary functionalization. The study of the first level of association of these compounds by viscosimetry, ITC and SANS showed that the use of bridged CDs allows the polymerization by suppressing the self-inclusion phenomenon. As a result, we developed two tunable cationic supramolecular polymers (SMP) based on functionalized β-CD with relatively high polymerization degrees. Their ability to form hierarchical SMP with rigid polyanionic species was then assessed by DLS, spectroscopy and cryo-TEM. In optimized concentration and charge ratio conditions, three different water-soluble hierarchical assemblies were formed. We showed that the first level of association and the high directionality of the secondary interactions are key parameters to achieve these stable, well-defined, hierarchical assemblies. These tunable structures will be therefore used as a platform to get greater insight into hierarchical assembling processes
Agnaou, Reda. "Polymères supramoléculaires semi-cristallins à base de Polyamides et PMMA". Electronic Thesis or Diss., Paris 6, 2014. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2014PA066544.pdf.
Texto completoDesign of materials with polymer-like properties at service temperature but able to flow like simple liquids when heated remains one of the important challenges of supramolecular chemistry. Combining these antagonistic properties is highly desirable to provide durability, processability, and recyclability of materials. Here, we explore a new strategy based on polycondensation reactions to design supramolecular polymer materials with stress at break above 10 MPa and melt viscosity lower than 1 Pa·s. We describe the synthesis and rheological and mechanical properties (uniaxial tensile tests) of supramolecular polymers based on a multiblock polyamide architecture. The flexibility of polycondensation reactions made it possible to control the molecular size distribution, the strength of hydrogen bonds, and the crystallization of middle and end groups and to achieve targeted properties. A second family of supramolecular polymers, based on a PMMA backbone, was designed and synthesized by ATRP or RAFT polymerization. Controlled radical polymerization enabled precise control over molecular weight and chemical modification of the oligomers allowed us to obtain supramolecular PMMA terminated at both ends by associative groups. Thermal, mechanical and rheological properties of this supramolecular polymer are described
Goujon, Laurent. "Élaboration d’un dispositif électroémissif flexible à base de réseaux interpénétrés de polymères". Thesis, Cergy-Pontoise, 2011. http://www.theses.fr/2011CERG0532/document.
Texto completoDuring this thesis a thin (140 µm) and flexible electroemissive device (EED), based on interpenetrating polymer networks (IPN), was elaborated. An electronic conducting polymer, poly (3,4-ethylenedioxythiophene) (PEDOT), is interpenetrated in a host matrix to obtain a system whose monoblock architecture is comparable to a three-layers device. Once the system is swollen by an ionic liquid, 1-ethyl-3-methylimidazolium bis-trifluoromethyl sulfonylimide (EMImTFSI), the EED optical properties are tunable between 24 and 51% reflection in the mid-infrared (Band III) by varying the electrical voltage applied across the device from -1.5 V to +1.5 V. The EED thermomechanical properties are mainly from the host matrix. This is an IPN combining flexibility and tensile strength of nitrile butadiene rubber (NBR) with the ionic conductivity properties of poly (ethylene oxide) (PEO) in the presence of EMImTFSI
Vancaeyzeele, Cédric. "Synthèse et caractérisation de réseaux interpénétrés de polymères à base de polyisobutène". Cergy-Pontoise, 2004. http://www.theses.fr/2004CERG0202.
Texto completoNew based polyisobutène (PIB) materials have been synthesized. First PIB single networks from different polyisobutène telechelic and different way of synthesis have been carried out and characterized. These single networks are then associated with another plastomer network into interpenetrated polymer networks (IPNs), two entangled networks without covalent bounds between them. These IPNs are synthesis in situ and the best interpenetration degree is obtained when the PIB network is first formed. Thus, PIB/PS IPNs are synthesized in order to improve PIB network mechanical properties and there morphologie depends on the weight proportion of each component. When PIB amount is bigger than PS amount, spherical PS domains are dispersed into PIB matrix and the material has good damping properties. But when PIB amount is lower than PS amount, both phases are co-continuous and material is rigid. These IPNs have improved ageing resistance under UV than PIB or PS single network. Thus IPNs structure protect polymer against outside attack. PMMA Matrix with PIB domains dispersed should allow building a transparent impact resistant material. But this morphologie has not been obtained. However, with polycyclohexyl methacrylate (PCHMA), all the IPNs PIB/PCHMA are transparent, flexible and a little bite elastic. Their high interpenetration degree between the two polymers is characterized by a new glass transition appearance between 30 and 110ʿC, temperature at which IPNs are shock absorber
Renaud, Cédric. "Étude des défauts électriquement actifs dans les dispositifs à base de matériaux organiques". Nantes, 2008. http://www.theses.fr/2008NANT2060.
Texto completoIn this work, the electrically active defects have been investigated from the measurements of thermally released charges in organic light emitting diodes. The electrical characterisation of defects has been studied in devices in order to understand their influence on the interfaces, the ageing and the doping processes. The investigation on the electrode influences in two types of polymers based on polydiacethylene and polyfluorene have shown the trap formations in the vicinity of electrode-polymer interfaces, especially that formed between the hole injection layer and the active polymer. The study of electrical ageing of diodes has shown an increase of the defect densities already present in the fresh device without changing their nature. The influence of doping process on the trap characteristics in polymers have been investigated by using two types of doping: by inorganic small particles and by phosphorescent organometallic materials. Both studies have shown that the doping of organic materials change the electronic structure of semiconducting layers of devices. The doping leads to the creation of trap levels and the reduction of the trap densities present in undoped polymer. These investigations shed new light on defect formations for the optimization of diode performances
Longhin, Marco. "Étude d’alliages à base de CoSi et de composites à base de polymères pour la thermoélectricité". Thesis, Montpellier, Ecole nationale supérieure de chimie, 2015. http://www.theses.fr/2015ENCM0002.
Texto completoWasted heat recovery through thermoelectricity can contribute to a more sustainable energetic model. For a large-scale application of thermoelectric devices, their efficiency is not the only criterion to consider; materials should be easy to synthesize and made of abundant, cheap and environmental friendly elements. Silicides and composites are little known thermoelectric materials that meet all these requirements. We studied the cobalt silicide CoSi and some alloys and composites obtained using this phase.Firstly we investigate whether nanostructuration allows increasing the thermoelectric properties of CoSi. CoSi crystallites with a size of 13 nm were synthesized by arc melting followed by mechanical milling or by mechanical alloying. These powders showed good chemical stability and a limited grain growth up to 400 °C. At higher temperatures grain coarsening is accompanied by a loss of silicon and the formation of Co2Si. The thermal conductivity of CoSi was reduced by 35% by nanostructuring. A ZT=0.15 was obtained at T=300 °C, which is higher than that of CoSi synthesized by arc melting but slightly lower than that of CoSi single crystals.Various elements were considered in order to form a solid solution with CoSi, taking into account common sense considerations and the results of ab initio calculations. We observed that Ca, Zr, Nb, Mo, Sn, Ta, W and Pb are not soluble while Ti, V and Cu have a limited solubility. The phases Co0.85Cr0.15Si, Co0.90Mn0.10Si and CoSi0.92Zn0.08 were also synthesized but the first two have a lower power factor than CoSi.We compared three commercially available intrinsically conducting polymers: polyaniline (PANI), polypyrrole (PPy) and polyethylene (3,4dioxythiophene) doped with polystyrene sulfonate (PEDOT: PSS). PPy demonstrated to be the best polymer to form composites containing Co0.85Fe0.15Si. The highest power factor, PF=2.5 μW/m.K2, is obtained for a volume fraction of polymer ϕ=10%, nonetheless this composition induces poor mechanical strength. The thermoelectric performances we measured were always inferior to the ones of inorganic phase, thus the main advantage of these composites is their ease of shaping
Teyssandier, Fabien. "Formulation et morphologies de mélanges de polymères thermoplastiques à base d'amidon". Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00708484.
Texto completoEiamlamai, Priew. "Electrolytes polymères à base de liquides ioniques pour batteries au lithium". Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GRENI016/document.
Texto completoThe new families of lithium-conducting ionic liquids; aromatic and aliphatic lithium salts based on perfluorosulfonate and perfluorosulfonylimide anions attached to an oligoether (methoxy polyethylene glycol mPEG) with different lengths were synthesized and characterized with the aim to improve the salt interaction with the host polymer's POE chains while keeping a high segmental mobility. They allowed obtaining membranes with lower crystallization degree and higher cationic transport number as compared with benchmarked salts. Their properties as lithium salts were investigated in two types of host polymers i.e. a linear polyether (POE) and a cross-linked polyether prepared by a ‘GREEN' process. Their oligooxyethylene moieties improve the lithium cation solvation leading to an increase in cationic transference numbers. Their electrochemical and thermal stabilities are suitable for lithium battery application
Gingras, Émilie. "Synthèse et caractérisation de polymères ioniques à base de 2,7-carbazole". Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27554/27554.pdf.
Texto completoBouguettaya, Mohamed. "Elaboration de nouveaux adhésifs conducteurs d'éléctricité à base de polymères conjugués". Paris 13, 1998. http://www.theses.fr/1998PA132058.
Texto completoVelazquez, Morales Patricia. "Synthèse et caractérisation de nouveaux électrolytes polymères à base de chitosane". Grenoble INPG, 1997. http://www.theses.fr/1997INPG0119.
Texto completoBechu, Damien. "Polymères de coordination cristallins conducteurs à base de dérivés du tétrathiafulvalène". Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAF018.
Texto completoPorous coordination polymers or Metal-Organic Frameworks (MOFs) are crystalline architectures displaying interesting properties such as gas storage, gas separation and catalysis. Investigations described in this PhD dissertation focused on a property less explored for these materials, using coordinating tetrathiafulvalene (TTF) derivatives: electronic conductivity. Two approaches have been studied to promote an efficient conductivity pathway. In a first part, a series of symmetrical coordinating TTFs bearing thioether-pyridine or thio-pyridine spacers were synthesized. These TTFs were then employed for the formation of interpenetrated systems to generate stacks of electro-active moieties in the solid state. In a second part, a dissymmetrical TTF was developed and implemented in an alternative approach involving the formation of stacks of sulfur-rich units through interdigitation. This strategy allowed the synthesis of two isostructural materials. Studies of the oxidation state of the TTF within the networks were performed by EPR spectroscopy, followed by measurements of the electronic conductivity of these networks. In a third part, the interdigitation approach has been successfully extended to homo and heteroleptic dithiolene complexes
Bechara, Rony. "Élaboration et caractérisation de cellules photovoltaïques à base de polymères semiconducteurs". Strasbourg, 2009. https://publication-theses.unistra.fr/restreint/theses_doctorat/2009/BECHARA_Rony_2009.pdf.
Texto completoThis work reports on the elaboration and characterization of bulk heterojunction (BHJ) solar cells based on novel semiconducting photoactive polymers in aim of improving morphology, thermodynamic stability and absorption of the BHJ active layer. In the first section of this work, P3HT/PCBM standard photovoltaic devices was processed and characterized in order to develop an efficient process for organic solar cells production and optoelectronic characterization. The reliability of our experimental protocol was supported by the excellent results achieved on these standard devices. In the second section, two original macromolecule approaches were investigated in view of controlling the active layer morphology of the P3HT/PCBM BHJ solar cells:1)The DHPT3 (alternating copolymer), used as nucleating agent for rr-P3HT crystallization. 2)The P3HT-PBA-C60 (Rod-coil block copolymers, using a rod block based on P3HT and C60 grafted PBA coil block), used in a first attempt, as a surfactant in P3HT/PCBM composite. The third section reports on a photophysical, electrochemical and electronic study of a new low band gap alternating copolymer (PTBzT²-C12). This material has interesting optoelectronic properties and can be a good alternative for rr-P3HT in standard BHJ photovoltaic devices. The copolymers (DHPT3, P3HT-PBA-C60 and PTBzT2-C12) design and synthesis was carried out by our scientific team
Cunha, Christian da. "Polymères à base de fragments de lignine : synthèse et caractérisations structurales". Bordeaux 1, 1991. http://www.theses.fr/1991BOR10542.
Texto completoBabin, Perrine. "Matériaux alvéolaires à base de bio-polymères : structure et propriétés mécaniques". Grenoble INPG, 2005. http://www.theses.fr/2005INPG0094.
Texto completoThis work deals with the fine characterisation of the cellular structure of solid food foams, such as bread crumbs or extruded starches. The aim was, on one hand, to better understand the mechanisms governing the formation of this cellular structure and, on the other hand, to identify the microstructural characteristics influencing the mechanical properties. X-ray tomography allowed to get new quantitative results for these materials, especially cell or cell wall size distributions. Moreover, the latest developments in terms of time resolution allowed us to follow in situ and in extenso the proofing and the baking of bread dough. The different stages of the structure formation were analysed. The most part of the development takes place during the proofing through three succesive regimes : free growth of the bubbles, coexistence between growth and coalescence and finally, coalescence. The characteristic times delimiting these stages are function of the different composition studied. Ln parallel, Finite Element calculations were applied directly to the real structures (3D images) or to virtual numerical ones. Effective stiffness is deduced in relation with the different type of microstructures. Enrichment of the classical scaling laws is proposed, taking into account, not only the relative density, but also cell size distributions
Colesnic, Dmitri. "Architectures supramoléculaires hiérarchiques à base de cyclodextrines". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066616/document.
Texto completoBiological macromolecules and their assemblies (such as enzymes or viruses) perform extremely complex functions, thanks to their structural control. Our aim is to mimic such elaborated tools and build synthetic hierarchical assemblies using building blocks of cyclodextrin (CD). Using the known DIBAL-H reactivity for polyfonctionalization of CDs several monomers were prepared containing host-guest and electrostatic interactions. Thus, we demonstrated that a competitive self-inclusion and head to head dimerization prevent the formation of larger species in solution. To overcome this problem, a bridging strategy was used to cap the CD monomer and attach the two functionalized sugar units. This led to two types of building blocks (mono- and di-substituted) that showed different beahaviour. The monosubstituted compounds formed supramolecular oligomers in solution while disubstituted ones led to a hierarchical supramolecular self-assembly in the solid-state. Furthermore, efficient DNA compaction was performed involving hydrophobic interaction as a result of the use of monosubstituted positively charged CD building blocks. On the other hand, a single stranded DNA was used to control the size of CD-based supramolecular polymers. For this purpose, a CD monomer containing a hydrophobic moiety and a trinucleotide was developed. The host-guest and base pair interaction synergy allowed the formation of a stable DNA pseudo-duplex
Caille, Dominique. "Synthèse et propriétés de réseaux à base d’époxy et d'isocyanate". Lyon, INSA, 1991. http://www.theses.fr/1991ISAL0060.
Texto completoThe purpose of this thesis is to study the networks obtained from the reaction between a diepoxy and a diisocyanate. This materials possess two chemical species which are the oxazolidone bifunctional resulting from the addition reaction between an epoxy and an isocyanate. The second species is the isocyanurate, tridimensional, derived from the trimerization of the isocyanate groups. The preliminary study by DSC and FTIR leads· to identification of the temperature range of the two heterocycles formation reaction , By HPLC and NMR, the study of model mono functional molecules shows that there is a competition between the two reactions described above and the homopolymerization of the epoxy groups present in the reaction mixture. The viscoelastic properties of the networks are determined using the polymers obtain from a diepoxy and a diisocyanate. These mechanical properties are interesting but decrease rapidly high temperatures in the presence of oxygen. The network structures before and after oxidation are studied by 13C NMR wîth Magic Angle spinning
Wable, Clémence. "Synthèse, structure et propriétés d’hydrogels hybrides à base de polymères et de silicates". Paris 6, 2013. http://www.theses.fr/2013PA066193.
Texto completoWe report the synthesis and the characterization of transparent and purely elastic hybrid hydrogels of poly(N,N-dimethylacrylamide) (PDMA) and poly(acrylic acid) (PAA) swollen by potassium silicate solutions. The structure and properties of each organic and inorganic part of these original systems are controlled by a large number of parameters. A 4-steps approach is proposed to identify progressively the phenomena controlling the structure properties relationships. On the basis of the phantom network model, the analysis of the mechanical (compression, creep) and thermodynamic (swelling) properties of PAA and PDMA gels prepared in water allowed to identify and to quantify topological defects in gel structures; these latter being more important in the case of PAA gels. The introduction of KOH during the synthesis has two main effects on the structure and properties of the hydrogels: a chemical degradation of the monomers, leading to a decrease of elastic moduli, as well as a modification of defect proportion in the network structure. Gels prepared in presence of colloidal silica particles have also been investigated. For PDMA, we checked the polymer chains adsorption on silica surfaces and characterized its influence on the mechanical properties. In the case of PAA chains, it was not possible to obtain a transparent gel. Finally, transparent PAA/silicates gels have been prepared by simultaneous polymerization of the organic network and silica dissolution. The gels present a purely elastic behavior determined by the PAA concentration as well as by the competition, in basic medium, between the silica dissolution and the chemical degradation of the organic monomers
Noël, Marion. "Elaboration d'un matériau composite innovant à base de bois et de bio-polymère d'acide lactique". Nancy 1, 2007. http://docnum.univ-lorraine.fr/public/SCD_T_2007_0061_NOEL.pdf.
Texto completoComposites from petroleum based polymers and synthetical or mineral fibers can be advantageously replaced by biomaterials from biopolymers and vegetal fibrous reinforcements, allowing recycling and /or biodegradation at the end of their lifecycle. In this purpose, we prepared a wood / lactic acid biopolymer based bio composite. Wood vacuum / pressure impregnation by lactic acid oligomers containing chemical catalyst or not, was followed by a heating process in a drying kiln. The aim of this study was to induce oligomers polymerization into the wood cells, and a potential grafting on the free hydroxyls wood groups, in order to improve wood properties. We showed an effective in-situ polymerization, and a strong interaction between wood and biopolymers chains, however not grafted. The biopolymer impact on the lignocellulosic structure is shown by a significant softening of wood, occurring at an intermediate level of the heating process, probably due to a reaction between lactic acid oligomers and the lignin mainly contained into the middle lamella. The material darkening suggests a probable reaction between chemical catalysts and cellulose. Once the heating process has been completed, the composite gets stiff. The treatment imparts an excellent dimensional stability to the wood composite : an anti swelling efficiency approaching 70%. A good antifungal resistance is also noticed. As for mechanical properties, bending and compression resistances are slightly influenced, while hardness is significantly improved, and shearing resistance altered, due to the middle lamella degradation. Therefore, high density and hardness, plus a good material stability could be valorized by industrial uses such as flooring. In the intermediate state, moulding applications are also conceivable
Dang, Minh Trung. "Elaboration de cellules solaires photovoltaïques à base de polymères conjugués : études des systèmes réticulables". Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13892/document.
Texto completoThis contribution deals with the elaboration of polymer-based photovoltaic solar cells. At first, this work was devoted to validate the experimental procedure in our laboratory. We fabricated cells consisting of the conjugated polymer poly (3-hexylthiophene) (P3HT, electron donor) blended with a fullerene derivate [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM, electron acceptor). The optical, morphological and photovoltaic properties of cells with a structure of ITO/PEDOT: PSS/P3HT: PCBM/Al has been investigated. We showed the influence of the ambient atmosphere during weighing of compounds or during solution processing. We also studied many parameters such as the active layer thickness, the polymer molecular weight, the solvent nature and the spinning acceleration time. We studied the effect of solvent and thermal annealing treatment on the performance of organic solar cells. The power conversion efficiency was significantly improved by insertion of a layer PEDOT: PSS qualified as ?high conductivity grade?. This specific PEDOT: PSS limits the annealing temperature at 120°C since it dramatically decomposes at higher temperature. The addition of an ultra-thin LiF layer (1 nm) improved significantly the performances. We studied the potential of crosslinkable molecules as active layer: polythiophene and perylene derivatives with specific crosslinkable moities in order to improve the durability of devices. These molecules were able to crosslink by sol-gel method or UV- irradiation. However, the power conversion efficiency of cells was extremely low due to the attack of ITO by acid or due to catalysts involved
Vechambre, Cyril. "Mémoire de forme et matériaux à base d'amidon : propriétés et mécanismes impliqués". Nantes, 2011. https://archive.bu.univ-nantes.fr/pollux/show/show?id=4c6af3be-d8c6-4bfd-8995-6a4d3bbe640a.
Texto completoThe main objective of this study was to characterize the shape memory effect in extruded starch-based materials and to understand the related structure implicated in this particular effect. The shape memory performances of thermoplastic starch are very similar to those of most synthetic polymers, with for optimized conditions, a fixity about 98%, a shape recovery of 95% and a recovery stress close to 3MPa. Moreover, the shape change of starch-based materials can be triggered by both humidity and temperature. Synchrotron radiation polarized infrared microspectroscopy and wide angle x-ray scattering experiments evidence a orientation of amorphous segments and the presence of a local order constituted of helical fragments. This local order allow chains orientation without slippage. Shape recovery stimulated at the glass transition lead to a isotropic state. It has been shown that the deformation induce the formation of residual stresses, linearly dependent on the orientation of the amorphous chains. In the temporary shape a lower molecular mobility is observed. This lower mobility can results from the formation of a secondary network, created during the deformation and seems to be due to hydrogen bonds. The results are discussed in terms of usual mechanisms proposed for shape memory synthetic polymers
Okrasa, Lidia. "Relaxations moléculaires de composites polymères anisotropes à base de dérivés cellulosiques cristaux liquides". Lyon 1, 1999. http://www.theses.fr/1999LYO10021.
Texto completoGhannam, Leïla. "Pigments hybrides inorganique/organique colorés à base de mica". Pau, 2006. http://www.theses.fr/2006PAUU3011.
Texto completoThe principal aim of this study is the synthesis of inorganic/organic pigments based on mica that have special visual effects. These pigments differ either by their colour or by the presence of iridescent visual effects due to light interference. We have developed here two synthesis methods: - The first consists of coupling controlled radical polymerization and grafting process from mica surface. The main achievement of this method is the generation of a variety of coloured products thanks to the incorporation of pH-depending modified dyes into organic parts. The colour of these pigments depends on the polymer chains adsorption density, the incorporated dye quantity into these chains and on the chains conformation on mica surface in particular. Moreover, for these pigments kind, we have, synthesized a new multilayered pigment by modified dye, and styrene copolymerization by activation of polybutylacrylate end chains previously adsorbed from mica thanks to Nitroxide Mediated Polymerization. The naked eye observation of these pigments shows colour varieties and certain gloss levels. - While this first way is related to the formation of polymer layers with different refraction index on mica surface, the second way of pigment synthesis is based on the polymer films 2D organization. Visual iridescent effects were reached by selfassembly of polymers or copolymers prepared by NMP on honeycomb structure on sheet mica surfaces. The physicochemical and colorimetric characterization of different pigments synthesized show that these two methods have allowed us to attain our objectives: that means to obtain pigments with special visual effects from mica surface. These approaches represent an efficient tool to synthesize pigments and can be of great interest for pigment industries destined to many applications such as cosmetics, plastics, automobiles, etc
Bassil, Maria. "Muscles artificiels à base d'hydrogel électroactif". Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00688340.
Texto completoGaétane, Ceglia. "Elaboration et caractérisation de matériaux polymères poreux modèles à base d'émulsions contrôlées". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2001. http://tel.archives-ouvertes.fr/tel-00731266.
Texto completoHabrard, Florian. "Élaboration de dispositifs et matériaux mixtes à base de polymères conjugués électroluminescents". Phd thesis, Université Joseph Fourier (Grenoble), 2006. http://tel.archives-ouvertes.fr/tel-00130247.
Texto completoLagel, Marie-Christine. "Développement de nouveaux matériaux à base de polymères naturels et leurs applications". Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0178/document.
Texto completoWith the constant increase of oil prices and with the dwindling of fossil resources, "green" alternatives must be found. Thus, first research was conducted on the possibility to develop synthetic phenolic adhesives for wood-based panels where a part of phenol was substituted by wheat proteins. Similarly, tannins which are natural polyphenolic molecules can be used as an alternative to synthetic chemical products. Chestnut tannin, a hydrolysable tannin was used to substitute part of phenol during the synthesis of phenolic resins. The characteristics of these resins were studied and the resins used for the manufacture of rigid phenolic foams. This is a new step towards the development and future commercialization of more environmentally friendly materials. Furthermore, condensed flavonoid tannins were also used in the development of tannins-furanic biobased rigid foams. Quebracho wood tannin extract was coupled with furfuryl alcohol another material of natural, agricultural origin. These "green" foams show good mechanical strength, good thermal performance and do not burn, thus they are entirely suitable for use in building insulation. Finally, new types of materials made from the same natural products (tannins and furfuryl alcohol) were developed during the research described in this thesis: biobased abrasive and friction materials. Abrasive wheels and abrasive discs for steel molding and steel cutting using a biobased matrix were thus developed and tested. Moreover, automotive brake pads were prepared and were tested under real vehicle application conditions. All these new materials showed excellent properties compared to commercial materials and yielded excellent results comparable and sometime superior to their synthetic commercial equivalents
Guillaume, Maïté. "Supports chromatographiques énantiosélectifs à base de polymères de cyclodextrine : préparation, caractérisation, propriétés". Paris 12, 1995. http://www.theses.fr/1995PA120047.
Texto completoTbal, Hamid. "Synthèse et caractérisation de polymères macroporeux à base de vinylamine : Propriétés complexantes". Lille 1, 1989. http://www.theses.fr/1989LIL10040.
Texto completoHariri, Sahar. "Electrolytes polymères photoréticulables à base de chitosane, polyéthers et chromophores furaniques conjugués". Grenoble INPG, 2001. http://www.theses.fr/2001INPG0135.
Texto completoGardelein, Arnaud. "Conception d'un capteur électrooptique de rayonnement électromagnétique à base de matériaux polymères". Nantes, 2006. http://www.theses.fr/2006NANT2084.
Texto completoThe context of this work is telecommunication network. The purpose is to design a component which can transpose an information from microwave electric domain to the optical one. To improve the performances of existing systems, this work presents a low cost, passive and compact component, a microwave electrooptic antenna. This objective is achieved by using a crosslinkable polymer, PGMA/DR1. In this work we characterize the polymer material in the electrical domain using a capacty measurement method and in the electrooptical domain using a through plane simple relflexion technique. The component design is based on two optimisations. In the optical domain, we enhance the optical path length by using a Fabry-Perot cavity. In the electrical domain, we concentrate the microwave radiation by using a dipole antenna. Measurement shows that the compenent is functionnal but needs to be optimized
Kerbellec, Nicolas. "Polymères de coordination à base de Terres Rares : porosité et propriétés optiques". Rennes, INSA, 2007. http://www.theses.fr/2007ISAR0009.
Texto completoWe have developed a computational method that allows us to estimate the potential porosity of coordination polymers. This method, based only on crystallographic data, leads to a value which does not depend on sample geometry. It is particularly useful for studying coordination polymers with low thermal stability. It is also useful for comparing the potential porosity of materials with complex networks. We have been then interested in the development of lanthanide terephthalate compounds. All these compounds present only two type of crystallographic structure and one of them contains thirteen different lanthanides with the structure Ln2(TER)3(H2O)4. These compounds have been more particularly studied. We have synthesized nanoparticules using polymer encapsulation technique. Then we have worked on a new type of compounds which simultaneously contain several different lanthanides. The synergy between the different lanthanides ions leads to new compounds exhibiting original properties
Wantz, Guillaume. "Elaboration, caractérisation et optimisation de diodes électroluminescentes à base de polymères conjugués". Bordeaux 1, 2004. http://www.theses.fr/2004BOR12906.
Texto completoThis thesis deals with the study of polymer light-emitting diodes (PLEDs) which present many attractive properties to develop a new display technology. Poly(phenylenevinylene) derivatives (PPVs) such as MEH-PPV and BDMO-PPV have been studied. Three parts may be considered in this work. First, technological aspects related to device fabrication are studied, such as the electrode material choice or the effect of the ITO roughness on the performances of PLEDs. This roughness was found to be a critical parameter in terms of device lifetime. Then, charge transfer mechanisms through the polymer are evaluated by the study of the temperature dependence of current-voltage-luminance curves as well as of the temperature dependence of the electroluminescence spectra. Holes are found to be the majority charge carriers in PPVs. As a consequence, in the last part, device optimisation is made possible by addition of a specific vacuum evaporated molecular layer between the emissive polymer and the cathode to improve the charge balance
Ceglia, Gaétane. "Élaboration et caractérisation de matériaux polymères poreux modèles à base d’émulsions contrôlées". Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14462/document.
Texto completoPolymer foams are cellular materials commonly used for safety applications in many industrial sectors (aeronautic, passive safety, gears…). To even improve their performances, the link between their structural parameters (cell sizes, density...) and their mechanical behaviour should be better understood and modelled. A way of producing such foams is to polymerize the continuous phase of highly concentrated emulsions. The advantage of such an emulsion-based strategy is that it becomes possible to take advantage of the good control over emulsion parameters (drop size, dispersed phase volume fraction, continuous phase composition) to elaborate model foams with cells and pores having narrow size distributions. The production of model foams makes it possible to determine independently the influence of each parameter on the compression modulus and to compare the results with existing models
Nguyen, Ngoc Tan. "Transducteurs ultra fins à base de polymères conducteurs : fabrication, caractérisation et modélisation". Thesis, Valenciennes, 2018. http://www.theses.fr/2018VALE0036/document.
Texto completoRecently, ultrathin poly (3,4-ethylenedioxythiophene) (PEDOT) – based ionic actuators have overcome some initial obstacles to increase the potential for applications in microfabricateddevices. While microfabrication processing of trilayer actuators that involve no manual handling has been demonstrated, their mechanical performances remain limited for practical applications. The goal of this thesis is to optimize the transducers in thin films fabrication by micro technologies, fully characterize the electrochemomechanical properties of the resulting trilayers, and develop a model to simulate their bidirectional electromechanical ability (actuation and sensing). At first, ultrathin PEDOT-based trilayer actuators are fabricated via the vapor phase polymerization of 3,4-ethylenedioxythiophene combining with the layer by layer synthesis process. This constitutes the first full characterization of ionic PEDOT-based microactuators operating in air of such a small thickness (17 μm) having bending deformation and output force generation of 1% and 12 μN respectively. Secondly, electrical, electrochemical and mechanical properties of the resulting microactuators have been thoroughly studied. Non-linear characterization was extended to volumetric capacitance dependence on voltage window. Damping coefficient was characterized for the first time. Thirdly, a nonlinear multi-physics model was proposed as a method of simulating actuator and sensor responses in trilayers, represented using a Bond Graph formalism, and was able to implement all of the characterized parameters. The concordance between the simulations and the measurements confirmed the accuracy of the model in predicting the non-linear dynamic behavior of the actuators. In addition, the information extracted from the model also provided an insight into the critical parameters of the actuators and how they affect the actuator efficiency, as well as the energy distribution. Finally, a nouveau bidirectional electromechanical linear model was introduced to simulate the sensing ability of the trilayer transducer and was confirmed via experimental results in both frequency and time domains of a sinusoidal input displacement. The resulting actuators and the proposed models are promising for designing, optimizing, and controlling of the future soft microsystem devices where the use of polymer actuators should be essential
Puget, Marin. "Synergie magnéto-optique dans des polymères de coordination à base de lanthanides". Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S079/document.
Texto completoLanthanides are more and more studied by the scientific community and their use in devices and operating materials is exploding. These elements are indeed known to exhibit remarkable magnetic and luminescent properties. They are indeed particularly effective for the creation of singles molecule magnets or light emissive materials. In this thesis work, the synthesis, the crystal growth and the magnetic and photo-physical characterizations of new complexes that associates lanthanides and photo-active organic molecules are studied. The latter possess a " trans " and "cis" conformation and it is possible, thanks to a bright UV irradiation stimulus, to switch from one to the other one. This photo-isomerization leads to a modification of the properties of the complex in which they are part of. In the first part, four new complexes with DyIII, EuIII, TbIII and SmIII are presented. They are obtained thanks to the association of precursors of lanthanides and an organic molecule from the stilbene family: the 4-styrylpyridine. A strong modulation of the optical properties of these compounds led by the isomerization of the ligand is observed. It is highlighted that this one has a notable impact on the luminescent properties of these four compounds and on their color emission. Then, the influence of this isomerization on the magnetic properties of the complex with DyIII is studied. The second part consists of the extension of the study in lookalike photo-active molecules. The aim of this work is to characterize the influence of the change of a given chemical group on the photo-isomerization properties. A ligand that is closely related to 4-styrylpyridine containing a dimethyl-amino group, is associated with a DyIII ion. A new complex is obtained and its magnetic properties in the solid state and in solution are studied. Besides, the use of a new molecule containing a diethyl-amino group as well as an azobenzene part gave rise to two new compounds with DyIII and with TbIII. The impact of the isomerization of this ligand on the luminescent properties of the complex with TbIII and on the magnetic properties of the complex with DyIII is then studied. In the third part, the perspectives of evolution of the subject are presented. A first strategy consists is to use less protonatings solvents than the chloroform to observe a stronger photo-isomerization. The second strategy is to use a photo-switching magnetic ligand. A radical of the nitronyl nitroxide family substituted by a stilbene group was synthesized and coordinated to DyIII and TbIII ions. Their photophysical study is commented
Assi, Hala. "Nouveaux polymères de coordination à base de titane et de dérivés phénoliques". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV072/document.
Texto completoCrystalline Metal-Organic Frameworks MOFs are one of the most recent classes of crystalline porous coordination polymers. Due to the variety of their structure and composition, they are currently considered as promising candidates in various domains (gas storage, fluid separation, catalysis, biomedicine…). However, the literature on the photocatalytic activity of these solids has exploded only very recently, although the many advantages of using these materials as heterogeneous photocatalysts in comparison with classical semiconductors. Considering the well-established photocatalytic properties of TiO2, it seems logical to focus on titanium in order to design new MOFs for such applications. Nevertheless, because of the difficulty in controlling the reactivity of these ions in solution (especially out of the very acidic conditions), very few crystalline titanium-based MOFs have been described, among the numerous MOFs known in the literature. Thus, obtaining titanium-based MOFs in water and basic medium remains a big challenge. In our work, some strategies has been followed in order to benefice from the advantages of the titanium ions and at the same time confront their limitations by focusing on the exploration of the chemistry of Ti4+ ions (titanium alkoxides, complexes and oxo-clusters) with various polytopic ligands, especially hydroxycarboxylate and polycatecholate derivatives in order to design new stable titanium-based MOFs. Such ligands provide important advantages in comparison with pure carboxylates, such as a potentially higher structural diversity, stronger Ti-O bonds leading to an enhanced chemical stability in basic medium, and a strong absorption in the visible range ensured by ligand to metal charge transfer. On the other hand, the use of titanium molecular complexes or oxo-clusters will be a promising opportunity in order to control the spontaneous hydrolysis and the high activity of Ti4+ ions. By privileging the solvo- and hydrothermal synthesis using the «high-throughput system», these strategies lead to obtain new crystalline solids (molecular and 1D/2D/3D polymeric compounds). The synthesis, the structural characterization by a combination of different technics (X-ray diffraction, TGA analysis, IR spectroscopy, Solid State NMR, sorption measurement…), the study of some properties and the preliminary photocatalytic experiments (water splitting reaction) of these new solids will be discussed in this manuscript