Dissertations / Theses on the topic 'Silice hybride mésoporeuse'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 31 dissertations / theses for your research on the topic 'Silice hybride mésoporeuse.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
El, moujarrad Imane. "Nano-objets multifonctionnels pour la nanothermomètrie en milieu biologique : Etude de propriétés physiques sous confinement." Electronic Thesis or Diss., Université de Montpellier (2022-....), 2023. http://www.theses.fr/2023UMONS078.
Full textThe thesis work focuses on the development of multifunctional core/shell nanoplatforms including a functional core acting as a nanothermometer encapsulated in a PMO-type mesoporous hybrid silica layer. The elaboration of the systems was initially carried out according to the strategy of a mesoporous hybrid silica deposition on a silica-based condensed core ("hard template" strategy). A fundamental study of the structure, chemical nature and size of the shell is conducted using a multi-scale experimental approach. The nano-object size modulation in a range between 50 and 500 nm approximately has been demonstrated, as well as the modulation of the chemical composition based on the use of different bridged organosilane precursors. The results revealed that the organization of the mesopores of the layer is conditioned by the supramolecular interactions between organic substructures of the hybrid silica. The elaboration of a photoluminescent functional core doped with rare earths (β-NaYF4: Yb3+, Er3+) was then carried out, followed by the deposition of a hybrid layer in order to obtain multishell systems. These systems have been modified to introduce a hollow space between the two phases. The thermometric performance of the functional nanoparticles as a function of the confinement type were studied in detail on the basis of their photoluminescence response. The evaluation of the performance of the resulting nanothermometers is encouraging for applications in the biological field
Vibert, François. "Effet du nanoconfinement des silices mésoporeuses sur la durée de vie de radicaux centrés sur l'atome de soufre." Electronic Thesis or Diss., Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4799.
Full textThe aim of this study is to explore the behavior of sulfur-centered radicals in 2D-hexagonal nanostructured silicas. A large variety of silicas was synthesized by varying the nature and the loading of organic precursors. Synthesis of SBA-15 silicas functionalized with sulfanyl, sulfinyl and sulfonyl radicals precursors was achieved according to the sol-gel process. These nanostructured materials led to a dramatic enhancement in the lifetime of generated confined radicals.Alkyl- and arylsulfanyl radicals were formed by photolysis of thiols grafted in silicas. These radicals were trapped by tert-butylphenylnitrone and the resulting spin-adducts got their lifetime strongly enhanced as compared to the same experiment conducted with non-grafted precursors. Direct observation of arylsulfanyl radicals at room temperature was also achieved, the half-lifetime of which was recorded to be several days, even in the presence of dioxygen.Precursors containing a diazene framework grafted onto silica enabled the formation and direct observation of arylsulfanyl, arylsulfinyl and arylsulfonyl radicals by both photolysis at room temperature and thermolysis at 200 °C. Depending on the conditions, half-lifetimes of several hours were recorded for these radicals
Vibert, François. "Effet du nanoconfinement des silices mésoporeuses sur la durée de vie de radicaux centrés sur l'atome de soufre." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4799.
Full textThe aim of this study is to explore the behavior of sulfur-centered radicals in 2D-hexagonal nanostructured silicas. A large variety of silicas was synthesized by varying the nature and the loading of organic precursors. Synthesis of SBA-15 silicas functionalized with sulfanyl, sulfinyl and sulfonyl radicals precursors was achieved according to the sol-gel process. These nanostructured materials led to a dramatic enhancement in the lifetime of generated confined radicals.Alkyl- and arylsulfanyl radicals were formed by photolysis of thiols grafted in silicas. These radicals were trapped by tert-butylphenylnitrone and the resulting spin-adducts got their lifetime strongly enhanced as compared to the same experiment conducted with non-grafted precursors. Direct observation of arylsulfanyl radicals at room temperature was also achieved, the half-lifetime of which was recorded to be several days, even in the presence of dioxygen.Precursors containing a diazene framework grafted onto silica enabled the formation and direct observation of arylsulfanyl, arylsulfinyl and arylsulfonyl radicals by both photolysis at room temperature and thermolysis at 200 °C. Depending on the conditions, half-lifetimes of several hours were recorded for these radicals
Goubert-Renaudin, Stéphanie. "Synthèse, caractérisation et réactivité en milieu aqueux de matériaux à base de silice fonctionnalisée par des ligands dithiocarbamate et cyclame." Thesis, Nancy 1, 2007. http://www.theses.fr/2007NAN10127/document.
Full textDithiocarbamate- and cyclame-functionalized mesoporous silicas have been prepared and characterized. Their reactivity in aqueous medium has been investigated to evaluate their potential use as electrochemical sensors. A novel one-step route towards dithiocarbamate-silicas has been developed thanks to the original synthesis of siloxydithiocarbamate precursors. This is based on the direct grafting of the precursor onto the silica surface. Mesoporous silicas (ordered or not, i.e., K60, SBA15, MCM41) functionalized with dithiocarbamate moieties have thus been obtained. Analogous materials have also been prepared according to the sole two-step procedure available to date in the literature (reaction of CS2 onto an amino-silica). The interest of the proposed approach compared to the one previously reported is to access undamaged dithiocarbamate-modified silicas, free of remaining amino groups, displaying better efficiencies for Hg(II) uptake. Three cyclam derivatives bearing 1, 2 or 4 silylated arms have been grafted onto mesoporous silicas (K60 and SBA15). Increasing the silylation degree improves the material stability in aqueous medium without preventing the leaching of the organic moiety usually observed for amino-silicas. Higher stability of the material, poorer reactivity towards protons and Cu(II) binding have been noticed. Cu(II) uptake process seems to be rate-limited by the kinetics associated to complex formation rather than mass-transfer rates into the porous matrix. Incorporation of these materials into carbon paste electrodes has led to a selective amperometric sensor for Cu(II)
Matheron, Muriel. "Films mésoporeux hybrides organiques-inorganiques : synthèse, organisation des pores et application en optique ophtalmique." Phd thesis, Ecole Polytechnique X, 2005. http://pastel.archives-ouvertes.fr/pastel-00003326.
Full textRichard, Jason. "Nanoparticules de silices mésoporeuses ordonnées fonctionnalisées par des polymères : de l’écoconception aux propriétés." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2019. http://www.theses.fr/2019ENCM0013.
Full textThis work deals with the ecodesign of ordered mesoporous silica (SMO) functionalized by polymers, which combine the advantages of mesoporous materials and those of polymers. The materials were structured by polyion complex (PIC) micelles, formed by electrostatic complexation between a polyamine (oligochitosan) and a double-hydrophilic block copolymer (DHBC). The copolymer has a functional polyacid block and a neutral PEO block that remained anchored in silica walls during the sol-gel process. The functional groups were revealed in the mesopores after the release of polyamines induced by PIC micelle dissociation upon a pH change. During this thesis, we expanded the synthesis route to a variety of mesostructures, morphologies and acid functions (poly(acrylic acid), poly(sulfonic acid)). First, the mesostructure was controlled by modifying the pH, the length of the oligochitosan and the conformation of the DHBC (linear PEO or brush-like PAPEO), resulting in SMO with lamellar, 2D hexagonal, and spherical cubic structures. The results were interpreted in terms of PIC assemblies morphology changes and allowed establishing a phase diagram. Then, a method was developed to control particle growth and ensure their stabilization by replacing part of the structuring DHBC by a stabilizing polyacrylamide-based DHBC (PAM-b-PAA). Nanoparticles were obtained with adjustable sizes between 200 nm and 1000 nm, well-defined morphology and ordered structures. The dissociation of PIC micelles in materials was then optimized to synthesize materials with a high density of acid functions in their mesopores (2.7 per nm3). Various materials with controlled size, structure and acidity were thus obtained. They were evaluated as adsorbents, catalysts and proton conductors. Of particular interest are the strong polyacid functionalized materials, exhibiting a very high proton conductivity (> 0,02 S.cm-1) stable over days
Cheikh, Ibrahim Ajfane. "Synthèse des matériaux hybrides organiques inorganiques multifonctionnalisés." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20067/document.
Full textThe aim of this work was focused on the structuration and the functionalization of organic-inorganic hybrid materials by the sol-gel process.The synthesis and characterization of new proton conductive membranes for fuel cell proton exchange membrane (PMFC), was prepared in the first part. Hybrid membranes based on polyethylene glycol highly functionalized with sulfonic acid have been synthesized and characterized through a physicochemical and proton conductivity. They have good mechanical properties, a sufficient chemical stability and a performant proton conductivity to be used as an electrolyte in fuel cell proton exchange membrane.In the second part, we have developed hybrid mesoporous materials with porous multifunctionalized in the presence of surfactant nonionic block copolymer (P123). Two probes were used for this study: the proton exchange capacity and the control of the growth of gold nanoparticles in the pores
Charlot, Alexandre. "Synthèse et Evaluation de silices hybrides mésoporeuses pour l'extraction de l'uranium en milieu sulfurique." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2016. http://www.theses.fr/2016ENCM0006/document.
Full textNuclear industries are perpetually looking for technical, economic and environmental progresses. Important volumes of acidic waste are generated by nuclear plants of the front end. The extraction of uranium from these solutions is required to decontaminate effluents (decrease of the radioactivity) and value uranium (reincorporation in the cycle). Uranium leaching is mostly achieved using sulfuric acid leading to the production of aqueous effluents that contain a large grade of sulfate complexes. In such conditions, uranyl sulfate complexes constitute the predominant uranium species in solution and its extraction represents a real scientific and technological challenge. Commonly, precipitation, solvent extraction or solid phase extraction are used. The last one is particularly adapted for low grade solutions due to it weak environmental footprint (no solvent are handling) and the facility of the process involved (i.e. fixed bed column). Among the available solid-phase extraction candidates, hybrid mesoporous silicas get a crucial part. They develop a very high specific surface areas and a driven porosity which give them a high potential of extraction capacities.In this manuscript the tailoring and the evaluation of hybrid mesoporous silicas have been investigated. Firstly, the work focus on the organic part grafted by post-synthetic pathway, the N,N-dialkylcarbamoylphosphonate based molecules have been identified to get interesting extraction properties. This study emphasizes that acid groups are required and that alkyl substituents get a real importance in the extraction efficiency. On the second hand, the role of pore size has been investigated. The results obtained disclosed that pores size diameters directly impact the grafting ratio as well as the homogeneity of the material: (1) materials with a pore size below 3 nm are heterogeneously functionalized due to steric issues, (2) a homogeneous organic monolayer grafted onto the silica skeleton occurs when the pore size ranges from 3 nm to 20 nm and (3) functionalization of material having pore size above 30 nm results in an organic multilayer covalently linked to the surface. The organic self-organization drives the extraction efficiency, only monolayers lead to promising results. At the saturation state, two molecules are required to extract one uranyl ion. To describe the molecular scale of the uranyl complex onto the solid, the local structure has been investigated by a parametric study and spectroscopic techniques (IR, EXAFS and DRX). Results reveal that two diamido-phosphonates are involved in the uranyl extraction. By this work, it is shown how the molecular scale helps to understand the macroscopic phenomena.Finally, continuous extraction in a fixed bed column confirms the extractive properties obtained in batch mode experiments and points out the potential of such material to be reused several times without any damages
Sutra, Pierre. "Catalyseurs hybrides organiques-inorganiques. Ancrage de complexes organométalliques sur silices mésoporeuses nanostructurées." Montpellier 2, 1998. http://www.theses.fr/1998MON20117.
Full textBrulay, Guillaume. "Optimisation de la quantité de radicaux générés dans les silices hybrides mésoporeuses : synthèse, caractérisation, application." Electronic Thesis or Diss., Aix-Marseille, 2022. http://www.theses.fr/2022AIXM0575.
Full textThe aim of this work was the development of hybrid mesoporous silicas composed with high concentration of embedded transient radicals in order to use them as polarizing agent in DNP-NMR. First of all, quantitative yield in paramagnetic centers were obtained from unimolecular processed carried out under photoirradiation. The synthesis and optimization of photolysis conditions allowed to obtain functionalized silicas by transient radicals from good to quantitative yields. The reactivity difference of radical precursors was rationalized by the fragmentation mechanism and environmental constraints inside the walls of the silica structure which provided high yields. Polyradical systems were characterized by EPR spectroscopy. High life-time allows the evaluation of these new "persistent" radical species as polarizing agent for DNP-NMR
Boullanger, Arnaud. "Matériaux hybrides organiques - inorganiques. Structuration et contrôle de la multifonctionnalisation." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20065.
Full textMesostructured hybrid materials (organic-inorganic) were prepared according two different ways: the sol-gel process on the one hand, the assembly of molecular hybrid 'bricks' on the other. In the first part, we focused on the one-pot synthesis of monofunctionalised cubic silicas (SBA-16) through the sol-gel process. Different organic functions were successfully introduced within the pores of the material (SH, CN, Cl, PO(OEt)2 and acac). Their accessibility was brought to light by complexation of lanthanide salts (europium) by acac moieties, but also by growing of gold nanoparticles within the pores, regularly distributed thanks to the SH groups. Thanks to their small size (2 nm) and their high accessibility, these supported nanoparticles could be used as catalysts. Secondly, our study was extended to bifunctional materials. 2-D hexagonal silicas (SBA-15) were functionalised by one-step synthesis within both pores and walls. Several organic groups were covalently included within the structure, which then allowed us to confine very closely two kinds of nanoparticles, able to interact between themselves at nanometric scale. The bimetallic material is consequently qualified as 'interactive'. The last part was dedicated to a new approach for the synthesis of 3-D structured materials, consisting in the assembly of hybrid molecular 'cages' (functionalised octasilsesquioxanes). Chloro terminations were chosen because of their easy conversion into acid or ionic moieties, able to self-assemble, driven by weak interactions such as H-bonds or electrostatic forces. The use of organic “linkers” such as cyclam groups was also considered to connect cages and anchor metallic ions
Blas, Hélène. "Polymérisation radicalaire contrôlée par le nitroxyde SG1 à la surface de particules de silice mésoporeuse." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00813166.
Full textYune, Jeremy. "Immobilisation des oxazaborolidines par liaison covalente sur silices mésoporeuses pour la réduction énantiosélective de cétones." Montpellier 2, 2009. http://www.theses.fr/2009MON20095.
Full textCardoso, Laura. "Assemblage colloïdal pour l'élaboration de matériaux hybrides polysaccharide-silice. Interactions, interfaces et textures." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2015. http://www.theses.fr/2015ENCM0010.
Full textThe major aim of this PhD thesis has been to study the formation of polysaccharides metal oxides hybrid materials through colloidal assembly. It concerns both the understanding of the mechanisms and the obtention of new materials and textures. To that purpose, we first studied suspensions of the colloidal precursors (chitin nanorods and siloxane oligomers). By mapping out the phase diagrams, we demonstrated that co-suspensions in ethanol exhibit self-assembly properties, similar to those obtained with chitin in aqueous medium, leading to the formation of chiral nematic mesophases. Besides, the rheological study of these complex fluids showed a great influence of the relative proportions of the precursors upon viscosity, hence revealing the major role played by colloidal interactions. Moreover, electron microscopy observations allowed us to confirm the formation of hybrid nanorods colloids made of chitin and silica within the co-suspensions. Then, we elaborated new composite materials either by changing the polysaccharide precursor (cellulose vs. chitin) or by introducing new precursors of inorganic phases (Al2O3, TiO2, ZnS). The characterization of these materials allowed us to estimate the impact of precursors' characteristics (surface chemistry, nature and size) on colloidal interactions and final textural properties. Lastly, we investigated the influence of the materials morphology and processing method – microspheres by spray-drying, fibers by electrospinning, thin films – and application of external fields – electric field, shearing – on the obtained materials characteristics. Based on these new results, we propose a mechanism of formation which enables us to envision the synthesis of functional materials with properties adjusted to intended applications (catalysis, mechanical properties…)
Saint-Cricq-Riviere, Philippe. "Matériaux hybrides fonctionnels photoactifs: Stratégie d'élaboration, caractérisation et activité." Phd thesis, Université de Pau et des Pays de l'Adour, 2009. http://tel.archives-ouvertes.fr/tel-00474544.
Full textChen, Pengkun. "Titania and silica based hybrid porous nanomaterials : from synthesis to applications." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF010/document.
Full textMy PhD research focus on the synthesis, characterization and applications of silica, titania and zeolite based porous materials. Porous silica, titania and zeolite have been synthesized using different methodologies. Functionalized silica materials have been used for dye adsorption application which is useful for water treatment. A new cross-linked system and device have been created to enhance the adsorption ability and for large quantity of water treatment. By taking advantage of the pores, new method for Cu(0) cluster formation have been established. The photophysics of the Cu(0) clusters reduced from different copper source in different porous materials has been investigated. The use of the confinement for sensing has been demonstrated for small bio molecules, such as neurotransmitters. Several applications have been developed based on this artificial neurotransmitter receptors. Multi-functionalized mesoporous titania material has been used for bio-applications. Compare to the widely used silica material, its photoactivity could bring extra advantages. Finally, new types of hybrid organotitanium materials have been developed and their photocatalytic properties have been investigated
Maouacine, Koceila. "Matériaux hybrides poreux silice/polymère comme électrolytes pour batterie lithium-ion tout solide." Electronic Thesis or Diss., Aix-Marseille, 2023. http://www.theses.fr/2023AIXM0024.
Full textThe design of lithium-ion batteries using a solid electrolyte is currently one of the most studied ways to overcome safety problem of these devices. In this thesis work, we propose a new approach to develop a porous silica/polymer hybrid electrolyte, containing a higher weight fraction of mesoporous silica than polymer. Two morphologies of silica hybrid materials were studied: as compressed powders (pellets) and as thin films. In the first part of the work, a hybrid silica powder was synthesized and then calcined to liberate the porosity. The mesoporous silica was then functionalized with different polymers of PEG of low molecular weight then by a simple solution impregnation. The hybrid powders were shaped as pellets, presenting inter- and intra-particle porosity. It was shown that the hybrid pellets present promising ionic conductivity properties when the inter- and intraparticle porosities are filled with the PEG-LiTFSI complex for PEG of low molar mass (300-600 g/mol). In the second part, mesoporous silica films were deposited on a glassy carbon electrode using a rotating disc electrode (RDE). After the characterization of these films from a textural properties and a microstructure point of view, they were functionalized by the PEG-LiTFSI complex via an impregnation process and the preliminary study of their ionic conductivity was performed
Shevchenko, Zaitseva Nataliya. "Matériaux mésoporeux hybrides organo-minéraux bi-fonctionnalisés : synthèse, caractérisation physico-chimique et application à l'élimination du chrome." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0075/document.
Full textThe present work proposes to examine chemical characteristics and behavior of two bifunctionalized silicas exhibiting either a mesostructure (i.e., MCM-41) or not (i.e., silica gel, denoted here SiO2) with respect to the immobilization of chromium species. The organo-functional groups selected to achieve this goal are mercaptopropyl and propylsulfonic acid moieties (MCM-SH,SO3H), on one hand, and mercaptopropyl and ethylenediaminetriacetate groups (SiO2-SH/ED3A) on the other hand. The research has been started with structurally ordered materials, of MCM-41 type, to ensure high surface area and easy and fast accessibility to the functional groups. On the basis of thiol-modified MCM-41, a set of sorbent samples containing different ratio of grafted mercaptopropyl and propylsulfonic acid groups (constant concentration of sulfur = 1 mmol g-1) has been synthesized. Special attention was first given to the characterization of surface chemical contents, which are expected to have a strong influence on sorption parameters. A simple, one-instrument method (conductometric titration) has been applied to the simultaneous determination of thiol- and sulfonic group on MCM-SH,SO3H. Then, the experimental conditions that are likely to provide effective sequestration of Cr(VI) on MCM-SH,SO3H have been defined, notably by studying the effect of pH, solid-to-solution ratio, or composition of the adsorbent (i.e., SH/SO3H ratio). On the basis of received data, a reduction-sorption mechanism explaining the uptake process has been proposed. In a second approach, a second type of bi-functional silica (SiO2-SH,ED3A) was suggested so as to improve the affinity (sorption properties) of the material to the reductively-generated Cr(III) species. Silica-gel was chosen as the matrix to graft controlled amounts of mercaptopropyl and ethylenediaminetriacetate groups at its surface. The performance of such bi-functional adsorbent was evaluated with respect to various experimental parameters likely to affect the reduction-sorption process (pH, solid-to-solution ratio, concentration) in order to determine the uptake mechanism and to compare it with the above adsorbent. Finally, it will be seen how this second adsorbent also offers the advantage of being usable in flowing conditions (column experiments)
Lemaire, Gaelle. "Elaboration de Nanoparticules hybrides et multiphasées innovantes pour la délivrance de principe actif." Thesis, Angers, 2017. http://www.theses.fr/2017ANGE0054.
Full textThe limitations of commercial nanovectors or currently under development have motivated the development of new hybrid and core shell mesoporous silica nanoparticles (MSNP) for the control of molecular delivery.Therefore, new MSNP were designed for intracellular penetration (diameter between 30 and 60 nm, pore size of 2.8 nm). In order to make them hemocompatible and to control the kinetics of delivery of encapsulated active ingredients, these MSNP were coated with a lipid bilayer (MSNP+@SLB-). The lipid composition is inspired by the asymmetric membranes of the red blood cells.Since the MSNP+@SLB- technology has shown some limitations associated to the release of payloads which can be too fast (in the case of calcein) or to slow (case of rhodamine B), two major improvements have been made:1- The coating of SLB by an alginate nanogel, allowing an excellent control of the release of active molecules.2- Insertion of magnetic nanoparticles in the MSNP core, triggering the release of the active ingredient by hyperthermia.These new nanovector architectures enable the fine tuning of active ingredient delivery kinetics, reinforcing and expanding the applications of silicated vectors in the fields of biomedicine (oral and intravenous) and dermato-cosmetics (topical)
Molina, Émilie. "Matériaux hybrides mésoporeux fonctionnalisés par des polymères : élaboration, caractérisation physico-chimique et applications biomédicales." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2015. http://www.theses.fr/2015ENCM0024.
Full textMesostructured hybrid materials were prepared by using original silica-structuring agents, which are polyion complex (PIC) micelles. A great advantage of PIC micelles is that they can be reversibly assembled in aqueous solution by varying physico-chemical parameters. PIC micelles are formed by electrostatic complexation between a neutral-anionic double-hydrophilic block copolymer (DHBC) and an oppositely charged agent of micellization; here a poly(ethylene oxide)-b-poly(acrylic acid) PEO-b-PAA (synthesized by controlled radical polymerization by atom transfer ATRP) and commercial polyamines (oligochitosan OC or aminoglycoside antibiotics) were respectively used. First, the influence of various parameters (pH, temperature, concentration) on PIC micelle association properties was investigated in aqueous solution. Then, the effect of these parameters on the silica mesostructuring process was studied, it provides a better understanding of the formation mechanisms. It was shown that varying interactions between constituents allows to control the mesostructure (hexagonal, lamellar, wormlike) and the material morphology (nanoparticle, microparticle). Finally, the versatility of the approach has been demonstrated with PEO-b-PAA/aminoglycoside systems. Drug-loaded ordered mesostructured materials were prepared following a one-pot route. Moreover, taking advantage of the high degree of functionality of DHBC polymers and of the reversibility of the micellization, polyacid-functionalized mesoporous materials were directly prepared by selectively extracting the micellization agent. PAA-functionalized silica materials were then used to complex diverse active entities such as drugs, whose delivery could be pH-controlled
Ménard, Mathilde. "Synthèse de nanoparticules hybrides de type coeur-coquille à visées théranostiques." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAE050/document.
Full textThe aim of this PhD work was to synthesize and test new nano-objects for the diagnosis and treatment of cancer. For this purpose, we developed hybrid nanoparticles made of an inorganic core surrounded by a human serum albumin (HSA) organic coating. The inorganic core is a composite by itself as it is made of an iron oxide core (IO) surrounded by a mesoporous silica (MS) shell. The IO core ensures, through its magnetic properties, diagnosis by magnetic resonance imaging (MRI) and therapy by magnetic hyperthermia, whereas the MS shell allows the loading of anticancer drugs for chemotherapy within its porosities. The pore sizes of the silica shell were modulated to enhance the drug loading content and the IO core size was also tuned to improve magnetic hyperthermia as well as T2 MRI imaging properties of the final core-shell system. The use of a thick shell of HSA as gatekeeper for controlled drug delivery triggered by its degradation with proteases was also studied. In parallel the synthesis of drug loaded HSA nanocapsules using MS as sacrificial template was performed. Finally, the biological activities of these nanoparticles were tested on various cancer cell lines
Grandsire, Anne-Flore. "Structuration et fonctionnalisation de matériaux hybrides organiques-inorganiques incorporant des fonctions polyéthers." Montpellier 2, 2009. http://www.theses.fr/2009MON20172.
Full textMakrygenni, Ourania. "Hybrids of Polyoxometalates supported on mesoporous silica and magnetic core-shell nanoparticles for anchored homogeneous catalysis." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066300/document.
Full textNew materials based on silica oxides (mesoporous silica SBA-15, magnetic core-shell nanoparticles) combined with nucleophilic hybrids of (vacant) polyoxometalates were elaborated for applications in the field of anchored homogeneous catalysis for mild oxidations reactions. The main parameter taken into account was the formation of a covalent bond between the support and the POMs. Two different pathways were followed depending upon the support used for the covalently grafting of POMs. Firstly, Keggin type POMs bearing carboxylic acid functions were grafted onto amino-functionalized SBA-15. Using the same support, other covalent immobilization methods were tried out, such as the use of a cross-linker. Secondly, hybrid nanocatalysts based on magnetic core-shell nanoparticles grafted with POMs were synthesized. All materials were characterized by a wide variety of physicochemical techniques. By HR TEM, the POMs were localized inside the pores of SBA-15 and onto the surface of magnetic core shell NPs, showing an excellent nanostructuration on the surface of both materials. Furthermore, the catalytic activity of the synthesized anchored homogeneous catalysts has been evaluated through the epoxidation of cyclooctene and cyclohenexe with H2O2 in acetonitrile, resulting in fairly good conversions in some cases, compared to the homogeneous systems used in this study. Finally, particular attention was paid to the excellent catalytic behavior of POMs bearing carboxylic acid functions compared to other POMs of the same family. Thus, DFT calculations were performed in order to identify the cause of this enhanced reactivity
Willai, Stéphanie. "Matériaux organosiliciés mésoporeux porteurs de β-cyclodextrine et de fonctions amines : synthèse par voie sol-gel structurante et propriétés." Lille 1, 2007. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2007/50376-2007-129.pdf.
Full textBirault, Albane. "Synthèse et caractérisation de silices hybrides fonctionnelles pour une délivrance autonome de molécules thérapeutiques." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2018. http://www.theses.fr/2018ENCM0010.
Full textThe work developed in this thesis is devoted to the design of functional hybrid silica platforms for controlled delivery of therapeutics (e.g. oncologic drugs, antibiotics, etc.) to improve their performance and limit their side effect. The different types of silylated hybrid materials synthesized and described herein, including (1) pH-sensitive nanoparticles; (2) multi-functional periodic mesoporous organosilicas (PMO) mesostructured via PIC micelles; and (3) sophisticated core-shell and raspberry-type PMO hybrids; demonstrate hierarchical organization over multiple length scales, providing appealing features for drug delivery applications.The manuscript focusses, in particular, on the mechanisms controlling pore nanostructuring, using different type of structuring agents (e.g. CTAB, polyion complex (PIC) micelles, silica seeds or decane droplets) and on the subsequent structure-function relationship. The research project also demonstrated the potential of specific systems for future applications in biomedicine articulated
Dol, Cyrielle. "Effet du nanoconfinement par des matériaux nanostructurés sur les propriétés des radicaux phénoxyle." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4739.
Full textAbstract : The aim of this study is to explore the influence of nanoconfinement on the phenoxyl radical behavior. A new methodology allowing the traceless solid state generation of phenoxyl radical was developed. It relies on the fragmentation of a diazene moieties and no solvent nor co-reagent are needed. A spin-trapping study was used to validate this approach. A wide variety of organic-inorganic hybrid materials, like mesoporous silica (SBA-15, MCM-41) and lamellar or porous polysilsesquioxane, functionalized with various phenoxyl radical precursors was synthesized. The spectroscopic properties of the phenoxyl radical contained in these materials were studied by EPR. These materials enable an amazing increase of the phenoxyl radical lifetime, they transform transient phenoxyl radical into persistent and even stable ones. The influence of the confinement has also been observed on the radical relaxation properties. Finally, an application of these materials as polymerization photo-initiator was successfully developed
Adem, Ziad. "Etude de la diffusion des hydrocarbures dans des matériaux à porosité contrôlée par RMN à gradients de champs pulsés (PFG)." Paris 6, 2008. http://www.theses.fr/2008PA066001.
Full textNabokoff, Pierre. "Synthèses de précurseurs organiques de radicaux hétéroatomiques pour la préparation de matériaux hybrides." Electronic Thesis or Diss., Aix-Marseille, 2020. http://theses.univ-amu.fr.lama.univ-amu.fr/201218_NABOKOFF_575sxytx526xlluw827l449jumhkc_TH.pdf.
Full textThe aim of this work was to investigate the influence of the nanocofinement on the behaviour of organic substrates embedded in mesoporous silicas. This research hinged on two parts. The first study focused on the efficiency of the fragmentation reaction of confined alkoxyamines, under thermal or photochemical activation. Thanks to the comparison with the very same reactions in solution, the quantitative EPR measurements showed that the confinement of organic precursors had no effect on the efficiency of these reactions. Secondly, organic-inorganic hybrid materials were synthesized. These mesoporous silicas were functionalized with diazene radical precursors. Upon 360 nm irradiation, they generated heteroatomic radicals. Different materials were prepared, including one which enabled to form a face-to-face pair of different radicals, i.e. an aryloxyl radical in front of an arylsulfanyl radical. Studies carried out by continuous and pulsed wave EPR enabled to highlight the high stability of these confined paramagnetic species and to measure their relaxation times
Dol, Cyrielle. "Effet du nanoconfinement par des matériaux nanostructurés sur les propriétés des radicaux phénoxyle." Electronic Thesis or Diss., Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4739.
Full textAbstract : The aim of this study is to explore the influence of nanoconfinement on the phenoxyl radical behavior. A new methodology allowing the traceless solid state generation of phenoxyl radical was developed. It relies on the fragmentation of a diazene moieties and no solvent nor co-reagent are needed. A spin-trapping study was used to validate this approach. A wide variety of organic-inorganic hybrid materials, like mesoporous silica (SBA-15, MCM-41) and lamellar or porous polysilsesquioxane, functionalized with various phenoxyl radical precursors was synthesized. The spectroscopic properties of the phenoxyl radical contained in these materials were studied by EPR. These materials enable an amazing increase of the phenoxyl radical lifetime, they transform transient phenoxyl radical into persistent and even stable ones. The influence of the confinement has also been observed on the radical relaxation properties. Finally, an application of these materials as polymerization photo-initiator was successfully developed
Zhou, Wen-Juan. "Polyamine and Schiff base metal complexes incorporated in mesostructured templated porous silicas : tentative application in selective oxidation." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2009. http://tel.archives-ouvertes.fr/tel-00533599.
Full textZhou, Wen-Juan. "Polyamine and Schiff base metal complexes incorporated in mesostructured templated porous silicas : tentative application in selective oxidation." Phd thesis, Lyon, École normale supérieure (sciences), 2009. http://www.theses.fr/2009ENSL0527.
Full textNovel materials were designed from hybrid organic-inorganic silica-based mesoporous materials containing Cu(II) complexes and were applied in selective oxidation reactions. The localization of the metal sites xas controlled using three different organosilane-ligands and two different synthétic routes, either the one-pot synthésis or the post-synthésis grafting. The Organosilanes were :N-(2-aminoéthyl)-3-aminopropyltriméthoxysilane (L1), N-salicylaldimine-propylamine-triméthoxysilane (L2) and N-(salicylaldimine) -(N'-propyltrimethoxyl silane)- diethylenetriamine, (L3). In addition, Ni(II) ion was used as structural probe. The Ni(II)-L1, Cu(II)-L1 and Cu(II)-L2 complexes were co-condensed with sodium silicate using the one-pot synthetic route in the presence of cetyltriméthylammonium tosylate as templating agent to built well-ordered periodix mesoporous organosilicas (PMOs) of MCM-41 type. The as-made materials were submitted to treatments using a mixture of chlorotriméthylsilane and hexamethyldisilazane or an appropriate amount of HCI washing to extract template and maintain the mesoporous structure. The Ni(II)-L1, Cu(II)-L1 or Cu(II)-L3 complexes have been also grafted in the performed mesoporous silica and evenly distributed using the a molecular stencil patterning technique. A multiple technique approach has been applied to thoroughly investigate the structure and morphology of the material as well as the coordination of the metal sites, using XRD, TEM, N2 sorption isotherms, elemental analysis, TGA, DRUV, FT-IR and EPR spectroscopies. In addition, the chemical accessibility and the leaching properties of the metal sites were tested using isothiocyanate (SCN-) as a ligand probe, metal displacemement of Ni(II) by Cu(II) ions or resistance to acidic leaching. Apart from the know channel species obtained from grafting that are solution-like, two different frame-work species were identified from their structural and chemical properties : the accessible and non-accessible ones, named « embedded » and « showing on » sites, respectively. The catalytic activity in phenol hydroxylation using hydrogen peroxide as oxiant and catechol oxidation reactions using dioxygen as oxidant depends on the metal location. Te grafted Cu(II)-L3 complex exhibited the best catalytic activities and was working in water solutions. The con- version and selectivity into valuable products, catechol and hydroquinone, were investigated in function of time, temperature, pH and substrate to oxidant ration. Catalyst recycling has been also investigated