Dissertations / Theses on the topic 'Copolymars composites'
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Granat, Cécile. "Étude des mécanismes d’auto-adhésion entre élastomère et matériau composite : Impact des paramètres de formulation et de mise en oeuvre des élastomères et du composite sur les caractéristiques de l’assemblage." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0054.
Full textIn many fields, in particular in aeronautic and aerospace, assemblies by bonding instead of bolting are used in order to lighten structures involving composite materials. Furthermore chemical bonding minimizes the risk of damage by fibers breaking. In this context, our research work concerns the assembly between a cured elastomer, known to be difficult to be bonded, and a composite material without using adhesives which are classified as carcinogenic, mutagenic and toxic agent. In order to have a good adhesion between cured EPDM elastomer and composite material with epoxy resin without adhesive, it is crucial to understand mechanisms of self assembly of these materials: role of physical bonds, influence of roughness, monomers diffusion and chemical reactions. This good understanding allows us editing material formulations, in our case copolymer in elastomer, to improve adhesion and remove surface treatment
Hamdoun, Bassam. "Composites copolymères/nanoparticules." Le Mans, 1995. http://www.theses.fr/1995LEMA1004.
Full textMa, Hongming. "Structure-property relationships in copolyester fibers and composite fibers." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04112004-150623/unrestricted/Ma%5FHongming%5F200405%5Fphd.pdf.
Full textCollard, David, Committee Co-Chair ; Schiraldi, David, Committee Member ; Liotta, Charles, Committee Member ; Weck, Marcus, Committee Member ; Srinivasarao, Mohan, Committee Member ; Kumar, Satish, Committee Co-Chair. Vita. Includes bibliographical references.
Basson, Nicolaas Christiaan. "The effect of molecular composition on the properties of polyolefin-wood composites." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80222.
Full textENGLISH ABSTRACT: Polymer composites, and in particular wood-polymer composites have become commercially and environmentally important materials. Studies in polyolefin-wood composites have mostly focused on polypropylene (PP) and polyethylene (PE). To our knowledge, no study has been undertaken on advancing impact polypropylene copolymer (IPPC)-wood composites as a suitable alternative to using PP and PE. IPPC have proven to be a suitable alternative to PP at low temperatures to improve impact resistance for manufactured polymer products, and could be a great addition to improved properties for wood polymer composites. This study shows that the physical properties of IPPC-wood composites can be markedly improved when compatibilizer(s) are used to improve the distribution of the wood within the matrix, as well as improving the interaction between the wood and the polymer matrix.. The use of different compatibilizers, vi polypropylene-graft-maleic anhydride (PPgMA) and poly(ethylene-co-vinyl alcohol) (EvOH) results in different physical properties. Using simple admixtures of the PPgMA and EvOH in IPPC-wood composites result in a large spread of results, while pre-reacting the PPgMA and EvOH to form a joint compatibilizer gives reproducible results w.r.t the physical testing. A study of the fundamental interactions of the compatibilizer(s) with the molecular components of the IPPCs was undertaken. The IPPCs used were fractionated by preparative temperature rising elution fractionation, and the fractions were mixed with the compatibilizers. To this end, fluorescence microscopy was utilized to study the interaction. The results clearly indicate that the interaction of the PPgMA with the fractions differ from that of the EvOH. These differences can be explained in terms of the chemical composition distribution within the IPPC fractions. Atomic force microscopy (AFM) was used to study adhesive forces between compatibilizer, polymer and cellulose and lignin. Successful coating of AFM tips with PPgMA and EvOH was achieved. Whilst interactions based on chemical force microscopy (CFM) could not be quantified, the AFM results in conjunction with fluorescence spectroscopy provided meaningful insight in the way that compatibilizers interact with both the wood and the impact copolymers used in this study.
AFRIKAANSE OPSOMMING: Polimeer saamgestelde material, en meer spesifiek hout-polimeer saamgestelde material het die afgelope tyd belangrike produkte geword, beide kommersieel en in verband met omgewingvriendelikheid. Navorsing op die gebied van poli(olefien)-hout komposiete het tot op hede meestal gefokus op die grbruik van poli(propileen) (PP) en poli(etileen) (PE). Sover dit on kennis strek is daar nog geen studie gedoen om die gebied van impak polipropileen kopolimere (IPPK)-hout komposiete uit te bou nie. IPPKs is ‘n geskikte alternatief vir PP in veral laetemperatuur aanwendings. Die gebruik van IPPKs as matriks vir die hout komposiete kan ‘n groot staqp vorentoe beteken. Hierdie studie wys dat die fisiese eienskappe van iPPK-hout komposiete merkwaardig verbeter kan word waneer versoeningmateriale gebruik word om die verspreiding van die hout in die polimeermatriks sowel as die interaksie tussen die hout en polimeer te verbeter. Die gebruik van verskillende versoenings material, t.w poli(propileen-ent-maleinsuur anhidried) (PPeMA) en pol(etlieen-ko-viniel alkohol) (EVOH). Deur gebruik te maak van eenvoudige mengsels van PPeMA en EVOH in IPPK-hout composite het ‘n geweldige wye verpreiding van resultate tot gevolg gehad, terwyl ‘n voorafgaande reaksie tussen die PPeMA en die EVOH om ‘n saamgestelde versoeningmateriaal te maak tot gevolg gehad het dat reproduseerbare resultate verkry kon word. ‘n Studie van die fundamentele interaksies van die versoeningsmateriale met die molkulêre komponente van die IPPKs is uitgevoer. Die IPPKs is gefraksioneer deur preparatiewe temperatuur-stygende uitloog frakasionering en die fraksies is gemeng met die versoeningmateriale. Fluoressensie mikroskopie is gebruik om hierdie interaksies te bestudeer. Die resultate dui duidelik daarop dat die interaksie van die PPeMA met die fraksies verskil met die van die EVOH. Die verskille kan verduidelik word aan die hand van die chemiese samestelling verspreiding van die IPPK fraksies. Atoomkrag mikroskopie (AKM) is gebruik om die adhesive-kragte tussen die versoeningmateriale, polimere, sellulose en lignien. AKM tippe is suksesvol bedek met PPeMA en EVOH, onderskeidelik. Alhoewel interaksies gebaseer op chemiese krag mikroskopie (CKM) nie gekwantifiseer kon word nie, lewer hierdie resultate tesame met die fluoressensie spektroskopie unieke insig in die manier wat versoeningmateriale met beide die hout en die polimeer reageer.
McElroy, C. R. "Composite materials from copolymers incorporating renewable resources." Thesis, Keele University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491843.
Full textJohns, Katharine. "Studies on composite copolymer particles." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284316.
Full textMarcilloux, Jérôme. "Contribution à l'étude de charges organiques pour matériaux composites à matrice élastomère : modification de surface de particules de polystyrène réticulées et encapsulation d'hydrocarbures polycycliques." Mulhouse, 1995. http://www.theses.fr/1995MULH0365.
Full textKalloudis, Michail. "Thin polymer films of block copolymers and blend/nanoparticle composites." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/7894.
Full textBier, Frédéric. "Conception et synthèse d’une matrice polymère thermoplastique pour l’obtention de matériaux composites recyclables, résistants au feu et utilisables dans l’industrie." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0040.
Full textNovel poly(methyl methacrylate) (PMMA) thermoplastic matrices which can be used in the elaboration of composite materials have been synthesized and characterized from the point of view of their glass transition temperature (by differential scanning calorimetry) and their thermal degradation (by thermogravimetric analysis and by pyrolysis combustion flow calorimetry). The strategy followed was to incorporate in the PMMA chains repeat units comprising a flame retardant phosphorous side group via a radical copolymerization of MMA with a phosphorus-containing monomer. A set of phosphorus-containing flame retardant monomers has been synthesized from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide (DOPO) by varying the nature of the polymerizable function (styrenic, acrylic, methacrylic), the nature of the atom bound to the phophore (oxygen, carbon, nitrogen) and the length of the spacer arm. We have shown that by adapting the structure and the quantity of the phosphorus repeating units, the glass transition temperature of the material was kept close to that of the PMMA while the thermal degradation of the materials was shifted to higher temperatures. Comparatively, physical blends of PMMA and DOPO with equivalent phosphorus contents exhibited significantly lower glass transition temperatures
Chang, Kaiguo. "Synthesis and characterization of conducting polymer-inorganic composite materials /." View online ; access limited to URI, 2000. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3108646.
Full textKanelidis, Ioannis [Verfasser]. "Polymer-Nanocrystal Composites: Copolymers, Polymeric Particles and Hybrid Systems / Ioannis Kanelidis." Wuppertal : Universitätsbibliothek Wuppertal, 2012. http://d-nb.info/1022590464/34.
Full textWang, Xuan. "Fabrication, structural and optical study of self-assembled hyperbolic metamaterial." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0694/document.
Full textNovel optical properties in the visible range are foreseen when organizing nanoresonators, which can be performed by the self-assembly of plasmonic nanoparticles prepared by wet chemistry. In this project, we use templating block copolymers structures to organize plasmonic particles. Our goal is to relate the structure of the prepared nanocomposites thin films, and in particular the nature, density and spatial organization of the nanoparticles, with their optical index.For this purpose, we first fabricate lamellar superlattices of diblock copolymers (poly(styrene)-block-poly(2-vinylpyridine) of controlled thickness (100nm-700nm), controlled lamellar period size(17 nm-70 nm) and optimized alignment and homogeneity. Following the fabrication of the multilayer templates, an in situ and reproducible synthesis of metallic nanoparticles was developed in order to generate nanocomposites selectively inside the P2VP layers. The size of Au nanoparticles can be well controlled around 7-10 nm. We also found that the reduction process could influence the shape (sphere, triangle or cylinder) and size by using different solvents or reducing agents. Because the extraction of accurate optical responses from the spectroscopic ellipsometry data, which will come in the last part, critically relies on the precise knowledge of the sample structure. We have used several experimental techniques to access a precise description of the produced materials. In particular, we used a Quartz Crystal Microbalance as a measurement tool to ‘kinetically’ study the volume fraction of Au loading. We find that the amount of gold in the composite layers can be varied up to typically 40 volume%. The optical properties of the nanocomposite films are determined by variable angle spectroscopic ellipsometry and analyzed by appropriately developed effective medium models. The films are structurally uniaxial and homogeneous, and we can define their dielectric permittivity tensor with the ordinary (parallel to the substrate) and extraordinary (normal to the substrate) components. The analysis of the lamellar structures allows the extraction of the components εo and εe, both presenting a resonance close to =540nm, with a significantly stronger amplitude for εo. When the gold load is high enough and the couplings between particles are strong enough, the values of εo become negative close to the resonance, and the material reaches the so-called hyperbolic regime, which constitutes a step towards applications in hyper-resolution imaging
Xie, Ming. "Sur la morphologie et les composites de copolymères éther bloc amide." Lyon, INSA, 1987. http://www.theses.fr/1987ISAL0013.
Full textNabi, Zia Ullah. "Deformation and fracture of ASA and its glass-filled composites." Thesis, London Metropolitan University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287616.
Full textBonnaud, Leïla. "Relations morphologiques : propriétés de matrices organiques modifiées et de leurs composites." Lyon, INSA, 1999. http://www.theses.fr/1999ISAL0082.
Full textIncorporation of thermoplastic (TP) modifiers bas been proposed as a method for enhancing the fracture strength of brittle epoxy - diamine system and toughness transfer from the matrix to unidirectional composite prepared by filamentary winding has been studied. Phase separation (SP) in initially miscible thermoplastic - epoxy - diamine occurs during the isothermal cure because of the increase in the molar mass of the growing thermoset (TS). TS systems contain two types of epoxy ( diglycidylether of bisphenol A (DGEBA) and triglycidyl of paraaminophenol (TGpAP)) and the hardener considered is a primary diamine, 4,4' –methylene bis[3-chloro 2,6-diethylan. Iline] (MCDEA). TP used are a polyetherimide (PEI), a polyethersulfone (PES) and a styrene-acrylonitrile copolymer (SAN). TP is always added in a 10% of blend content to have a TS continuous matrix. The control of morphologies generated during the reaction - induced phase separation procedure is essential to control the mechanical properties of fmal materials. This requires effective control of cure kinetics and the phase separation process. PEI and PES blends generated TP particulate morphology whereas SAN system generated a more complex structure composed of SAN particles and inverted phase areas with TS particles. The fracture toughness of blends was found to be significantly improved only when SAN is used. The synthesis and the use of backbone functionalized PEI shows an increase in the toughening ofbrittle epoxy matrix and a decrease of the diameters of the dispersed phase is observed. The presence of fibres is found to affect the final material morphology except in the case of grafted PEI system. For PEI systems, the fibres seem to act as a flow barrier to TP whereas in SAN case, the TS seems to accumulate around the fibers and SAN rich areas concentrate between TS layers. As in the matrix case, for composites, SAN based system is found to enhance more than PEI based system
Ishchenko, Olga. "Elaboration of plasmonic nano-composites and study of their specific catalytic activities." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAF042/document.
Full textThe objective of this thesis is to improve the photo-response of well-known photocatalytic material such as TiO2, which is usually only active in the UV range. The basic idea is to assemble several approaches within one device to improve the photocatalytic properties: fabrication of periodically-organised TiO2 nanostructures and their assembly with plasmonic nanoparticles. Two fabrication strategies were investigated for these purposes. The first approach consists of selective vapour phase growth. The second approach implements the use of an AAO template. In parallel, TiO2 films deposited by ALD and assembled with plasmonic gold nanoparticles are investigated. The photocatalytic measurements on various TiO2 architectures were performed in both irradiation ranges UV and Vis. A new fabrication approach of mesoporous H-TiO2 films was developed giving promising results of photocatalytic efficiency improvement in both UV and Visible ranges
Yau, Hon P. "Permeability of gases in copolymers, physical blends and composite particle materials." Thesis, Lancaster University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282409.
Full textGao, Renlong. "Synthesis and Properties of Ion-Containing Block and Segmented Copolymers and Their Composites." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77334.
Full textPh. D.
Gody, Guillaume. "Synthèse de monomères saccharidiques pour l'élaboration de glycopolymères à gradient, α-fonctionnels et à blocs par le procédé RAFT : application à l'immobilisation de biomolécules par reconnaissance spécifique ou par covalence." Lyon 1, 2008. http://www.theses.fr/2008LYO10302.
Full textIn the biological diagnosis field, glycopolymers are particularly interesting since they can be used either as support for covalent coupling of biomolecules or as multivalent architectures that favor the recognition processes with proteins. The purpose of this PhD thesis was the synthesis of original and well-defined gycopolymers, using a controlled radical polymerization technique, the RAFT process, with the aim of preparing new useful tools for diagnosis tests (capture and detection of nucleic acids and pathogenic agents). Five glycomonomers derived from D-galactose, D-mannose and N-acetyl-D-glucosamine were synthesized and then copolymerized with N-acryloylmorpholine (NAM) in the presence of three dithiobenzoate derivatives used as chain transfer agents (two of them bearing a biotin). Statistical copolymers (some -biotinylated) with various DPn in saccharide moieties were prepared in a controlled manner (Ip = 1,1-1,3). The “living” character of polymer chains was confirmed by preparing a diblock copolymer (consisting of NAM and N-acryloxysuccinimide (NAS) statistically copolymerized, thus providing lateral activated ester functional groups useful for further modification). Finally, three applications highlighted the potentialities of these glycopolymers : synthesis of “glycopolymer-ODN” conjugates using galactosylated glycopolymers ; preparation of biotinylated gold glyconanoparticules, characterized by Surface Plasmon Resonance (SPR) ; study of the specific recognition between mannosylated glycopolymers and lectin ConA by capillary electrophoresis
Yu, Zhong-Zhen. "Procédé d'extrusion réactive appliqué à l'élaboration de mélanges de polymères et de nano-composites." Vandoeuvre-les-Nancy, INPL, 2001. http://www.theses.fr/2001INPL018N.
Full textGuetta, Brigitte. "Vieillissement hygrothermique de composites a matrice psp : etude cinetique, mecanique et spectroscopique." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0057.
Full textLi, Haiying. "A study on grafting poly(p-phenylene terephthalamide) with aliphatic amines and amides." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/8594.
Full textMekhissi, Khaled. "Composites à matrice vinylester. Etude cinétique et mécanique." Montpellier 2, 2000. http://www.theses.fr/2000MON20025.
Full textShagolsem, Lenin S., and Jens-Uwe Sommer. "Diblock copolymer–selective nanoparticle mixtures in the lamellar phase confined between two parallel walls: a mean field model." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-139324.
Full textDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
Marcasuzaa, Pierre. "Composites conducteurs à base de PANI : vers une architecture contrôlée de 2D à 3D." Pau, 2009. http://www.theses.fr/2009PAUU3047.
Full textIntrinsically conducting polymers (ICPs) are a recent category of materials which currently make strong great strides. However, their main inconvenience is their insolubility in the usual solvents. That’s why lots of studies associate them with polymer matrices to make composites. During this study, conductive blocks copolymers with controlled architecture were obtained. These copolymers consist of a "matrix" block and a second conductive block. The first part, polystyrene or polyacrylate, is synthesized by controlled radical polymerization (ATRP) to control the molecular weight (between 5 000 and 15 000 g / mol) and the polydispersity (Ip). The conductive part is an oligomer of aniline. Then, both blocks are coupled to obtain a diblock copolymer. This synthesis is realized by conventional heating (bath of oil) and under microwave irradiation. Other architecture of copolymer is realized, it consists on the graft of polyaniline onto a natural polymer, the chitosane which brings coating properties, and the possibility of realizing hydrogels by crosslinking of grafting copolymer. So a network in which the PANI is distributed in a homogeneously is obtained
Frischinger, Isabelle. "Etude de matériaux composites polymères comportant une phase dispersée liquide : extension aux matériaux alvéolaires polymères/charges minérales." Mulhouse, 1989. http://www.theses.fr/1989MULH0117.
Full textCourbaron, Anne-Claude. "Gestion de la dispersion des MWNT par adsorption et greffage de copolymères PAA-PMMA pour le renforcement d’un polyépoxyde." Pau, 2010. http://www.theses.fr/2010PAUU3007.
Full textInterface between multi wall carbon nanotubes (MWNT) and epoxy matrix is admitted to play an important role in the dispersion quality and mechanical stress transfer. To improve the interfacial adhesion, we propose to chemically graft block copolymers onto MWNT surface using an “in situ” polymerisation. Herein, block copolymers are composed of one polyacrylic acid block (PAA) and one polymethyl methacrylate block (PMMA). The studies of polymerization kinetics, and cure epoxy showed the catalytic effect of MWNT. The grafting is highlighted by the study of copolymers degradation temperatures. Block copolymers make easier the MWNT dispersion in epoxy resin. MWNT grafted PAA-PMMA are more efficient than MWNT adsorbed PAA-PMMA, and give well dispersed nanotubes. The influence of copolymers proportion, molecular weight and grafting densities are also analyzed for the dispersion aspect. We characterized the mechanical properties of epoxy composites according to the dispersion quality and copolymers – MWNT interactions. It appears that when the interface is made compatible thanks to adsorbed or grafted copolymers, the rheological epoxy properties are clearly improved, especially with MWNT grafted PAA-PMMA which offer the best dispersion
Ramakrishnan, Karthik Ram. "Impact behaviour of sandwich structures with nanoparticle reinforced composite face sheets." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0042/document.
Full textSandwich structures are lightweight structures composed of two thin, relatively dense, high strength facesheets that are glued on either side of a thick, low density core, such as foams or honeycombs. Sandwich panels with fibre reinforced plastic skins and core of polymer foam represent an important class of lightweight structural materials in many areas of such as aeronautics and aerospace, automotive and marine structures. However, some of these sandwich structures have very limited energy absorption capacity. This limitation becomes critical because these structures are susceptible to be subjected to impact. The impact damage in the case of sandwich structures may be due, in particular, to dropped tools, flights debris, bird strike, hailstorms or ballistic impacts.The resins used as the matrix in the case of sandwich panels with laminated composite facesheets are usually thermosetting resins such as epoxy resins. Due to the fragile nature of the matrix, the presence of even a slight internal delamination spreads at right angles to the applied compressive stress with disastrous results for the sandwich structure. One of the proposed solutions is the modification of the thermosetting resins with the addition of organic and inorganic particles of nanometric size. A new method of synthesis of block copolymers that self-assemble at the nanoscale would substantially reduce the problems associated with the dispersion of nanoparticles.The objective of this work is to study and better understand the improvement of impact resistance of sandwich panels with skin laminates with the addition of tri-block copolymer (Nanostrength®) in the epoxy matrix of fibre / epoxy composite. The effect of nanoparticles on the mechanical performance of the sandwich Kevlar / epoxy or glass / epoxy facesheets and Rohacell® foam core panels will be investigated by comparing the results between pure resin and resin modified by the addition of 10% Nanostrength performed using experimental testing and numerical modelling. This work will focus on two different types of impact loading; low velocity impacts with normal angle of incidence to the sample surface and low velocity impacts with parabolic trajectory. A device for three-dimensional impact has been developed to study the mechanical response of sandwich panels subjected to a parabolic trajectory impact.The finite element method is a widely used method to study the impact on structures including sandwich structures. An LS-Dyna model was developed to simulate the normal impact of composite laminates and Kevlar / Epoxy - Rohacell® foam sandwich plates. A constitutive law based on damage mechanics, available in the material library of LS-Dyna called "Composite Laminated Fabric" (MAT58) was used to represent the behaviour of composite facesheets. The input parameters of the model MAT58 were obtained by combination of tests and parametric studies. The model "Crushable foam" (MAT63) was used for the core. The macroscopic model with a phenomenological law is able to simulate the mechanical response of composite laminates and sandwich plates subjected to low velocity impacts. It may be noted that the development of sandwich panels reinforced with triblock copolymer in the matrix is a promising field of study
Bhaway, Sarang M. "Fabrication of Block Copolymer Templated Mesoporous Metal Oxide Composites for Energy Storage Applications." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1468417723.
Full textShagolsem, Lenin S., and Jens-Uwe Sommer. "Diblock copolymer–selective nanoparticle mixtures in the lamellar phase confined between two parallel walls: a mean field model." Royal Society of Chemistry, 2012. https://tud.qucosa.de/id/qucosa%3A26773.
Full textDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
Overton, Bob James. "The effects of microstructure and styrene content on the rheological properties of styrene-butadiene random copolymers." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/10196.
Full textSaint-Aubin, Karell. "Etude de dispersions de nanotubes de carbone par des polymères pour l’élaboration de composites conducteurs et structurés." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14021/document.
Full textThis thesis deals with the study of carbon nanotube dispersions by polymers, the processing of composite films and the study of their mechanical and electrical properties. The first part of the work focuses on the use of poly(acrylic) acid (PAA), which proves to be an excellent dispersing agent in water. A study of the interactions between the PAA and the nanotubes is realised, tuned by the pH conditions. The fabrication of composite films, for future applications in the field of conductive inks and paints, shows that a fine control of the PAA adsorption and the dispersion stability allows the formation of homogeneous and conductive composites. In a second part, nanotube composites are elaborated from a block copolymer, the SBM, well-known for its remarkable self organization properties. Interestingly, the copolymer is at the same time the nanotube dispersing agent in the solvent and the structuring matrix of the final composite. This thesis shows that the copolymer structure, which strongly depends on the solvent used, influences the mechanical properties of composite films, and that the addition of nanotubes noticeably improves the performances
Robin, Jean-Jacques. "Synthèse et application d'agents de compatibilisation par ozonisation de polymères." Montpellier 2, 1989. http://www.theses.fr/1989MON20204.
Full textBéal, Ludovic. "Contrôle des interfaces dans les films nanocomposites." Chambéry, 2005. http://www.theses.fr/2005CHAMS031.
Full textThis work aims at studying the influence of block copolymers on properties of nanocomposite films composed of a poly(butyl methacrylate) matrix reinforced by silica nanoparticles, realized by mixing aqueous dispersions. First, a series of amphiphilic block copolymers composed of butyl methacrylate and methacrylic acid has been synthesized by anionic polymerization and thermal treatment. Aqueous micellar solutions of block copolymers have been characterized by nuclear magnetic resonance, by scattering techniques (Iight, neutron), by steric exclusion chromatography and by surface tension measurements. The behavior of block copolymers at latex/water interface was studied by adsorption of block copolymers at latex surface, by emulsion polymerization and by test of colloidal stability. Finally, the relationships between morphology and viscoelastic properties are studied on nanocomposite films as a function of silica content, fraction and composition of block copolymers
Chen, Jing. "Toughening epoxy polymers and carbon fibre composites with core-shell particles, block copolymers and silica nanoparticles." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14261.
Full textCosta, Christopher. "Elaboration de nouveaux élastomères thermoplastiques biosourcés à base d’huiles végétales." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0136.
Full textWith the purpose of expanding the Pebax® range, commercialised by Arkema, this study was dedicated to the synthesis of multiblock thermoplastic elastomers, including low glassy transition temperature bio-sourced soft blocks and rigid semi-cristalline polyamide. First, soft polyester and polyamide pre-polymers resulting from the polycondensation of commercialised dimerised fatty acids Pripol® (diol and diacid) and Priamine (diamine) as well as rigid PA-11 pre-polymers bearing amine or acid chain-ends, have been synthesized. From these pre-polymers, two distinct poly(ester-b-amide) (PEsBA) multiblock copolymer families containing variable ratios of amide functions and hard and soft phases have been elaborated, their properties and morphologies evaluated and compared to the ones of the reference: Arkema’s Pebax®. Second, new series of PEsBA copolymers have been prepared according to two synthetic processes, one in two steps not requiring the prior synthesis of the soft pre-polymer and the second, in one step, with no initially elaborated pre-polymers. The study of the structure-morphology-properties relationship of those copolymers allowed the discrimination of some of them exhibiting properties in agreement with the objectives. Lastly, starting from hard and soft polyamide pre-polymers, two new copolyamide (COPA) families have been synthesised and their properties compared to those of the established PEsBA and PEBA systems
Patel, Reena R. "Molecular dynamics simulations of polymer nanocomposites containing polyhedral oligomeric silsesquioxanes." MSSTATE, 2004. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04082004-135524/.
Full textRigon, Guacira dos Reis 1974. "Matrizes de compósitos de PLDLA com hidroxiapatita obtidas por rotofiação para utilização em engenharia tecidual." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263535.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Nos últimos anos, os polímeros biorreabsorvíveis ganharam importância na área médica e odontológica, sendo utilizados em um amplo número de aplicações no corpo humano, entre elas matrizes porosas tridimensionais como suporte no crescimento de células na área da engenharia tecidual. Com o objetivo de aperfeiçoar o processo de formação de matrizes como suporte na engenharia tecidual, estudou-se a utilização do compósito formado pelo copolímero PLDLA e um tipo de nanohidroxiapatita (HA) desenvolvida no laboratório de biomateriais da FEM/UNICAMP, na formação de matrizes através do processo de rotofiação. Os compósitos foram preparados utilizando-se 5% e 10% de HA em relação ao copolímero disperso em solvente clorofórmio na presença do surfactante ácido oléico. O processo de rotofiação é um processo simples, que forma uma matriz utilizando alta velocidade de rotação durante o jateamento da solução polimérica através de um orifício central sendo desnecessária, neste caso, a utilização de campo elétrico de alta voltagem, como ocorre para o processo de eletrofiação. As matrizes foram caracterizadas pelas técnicas de microscopia eletrônica de varredura (MEV), análise termogravimétrica (TGA), calorimetria diferencial de varredura (DSC), e espectroscopia de infravermelho com transformada de Fourier (FTIR). Os resultados obtidos pela microscopia eletrônica de varredura (MEV) mostraram que houve formação de uma matriz porosa e, portanto, o compósito pode ter uma aplicação promissora como suporte para cultura de células
Abstract: In the last years, bioresorbable polymers have been receiving more importance in the medical and dentistry areas, and they have been used in a large number of applications on the human body, such as tissue engineering scaffolds. This work studies the use of a composite of poly (L-co-DL-lactic acid) (PLDLA) and nanoparticles of hydroxyapatite developed at FEM/ UNICAMP to produce membranes by Rotary Jet Spinning process. Composites were prepared with 5% and 10% of HA in a clorophormium polymer solution. Rotary Jet spinning is a simple process to produce 3D structures that does not require a high-voltage electric field, like electrospinning. The results were characterized by the following methods: scanning electron microscopy (SEM), thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). The results from SEM showed that a porous membrane was obtained which could be used as scaffold in tissue engineering
Mestrado
Materiais e Processos de Fabricação
Mestra em Engenharia Mecânica
Zhang, Rui. "Polymeric Complexes and Composites for Aerospace and Biomedical Applications." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/96565.
Full textPHD
Lamy, Yoann. "Nanostructuration de résines polyester insaturé par des copolymères à blocs : application aux composites SMC et BMC." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00812588.
Full textDinu, Roxana-Mihaela. "Valorisation macromoléculaire des humines, de la kératine et des lignines par copolymères et composites durables." Thesis, Université Côte d'Azur, 2020. http://theses.univ-cotedazur.fr/2020COAZ4030.
Full textScientific and market researches are developed to replace the non-renewable fossil resources with renewable raw materials, and to reduce and valorise the industrial waste in order to develop new innovative green materials. Conversion of lignocellulose during acid-catalysed hydrolysis process leads to the valorisation of this biomass into value added chemical building blocks (HMF, FF, LA, etc.), but also provoke the formation of a dark-coloured by-product called humins. Feathers represent around 5‒7% of the corporal mass of an adult chicken, being one of the main wastes generated by the poultry industry. Knowing that the chicken feathers consist of 91% keratin, this side-product can be an important renewable source used as alternative for fossil derivative materials. The main objective of this thesis was the valorisation of humins and of chicken feathers in order to develop eco-friendly materials. Firstly, humins-based resins have been designed with modulable properties from elastic to rigid. Then, these humins-based resins were used for composites production with chicken feathers and lignin as bio-fillers. Thereafter, to produce fully bio-based thermoset resins, humins were copolymerized with phloroglucinol diglycidyl ether, a green epoxy comonomer from algae. Moreover, recyclable bio-based composites were developed by reinforcing humins-based thermoset resins with various natural non-woven fibers such as chicken feathers and vegetable fibers in order to develop eco-friendly materials for automotive industry. Finally, bio-based thermoset materials based on resorcinol diglycidyl ether, an aromatic epoxy compound derived from wood, and chicken feathers or lignin were developed. The studies developed in this thesis propose the synthesis, elaboration and characterization of several bio-resins and bio-composites fulfilling the criteria and requirements asked for an industrial valorisation
Amici, Marco. "Hybrid Inorganic / Organic polymers based on methacrylate - polyhedral oligomeric silsesquioxanes (POSS®) : morphology and structure - properties relationships." Lyon, INSA, 2006. http://theses.insa-lyon.fr/publication/2006ISAL0004/these.pdf.
Full textNovel hybrid inorganic/organic systems based on methacrylate and polyhedral oligomeric silsesquioxanes (POSS ®) have been synthesised and characterised. The synthesis has been performed via either thermally or UV free-radical polymerization. Chemical characterisation has been done with NMR, NIR and SEC. The POSS have been found to be polymerizable with the organic monomers once a good dispersion is ensured. Structure and morphology, characterised by means of SEM, TEM, AFM and WAXS, have been shown to be mainly dependent on the dispersion of the POSS in the organic matrix. Depending on the POSS grade and concentration, one could obtain a wide array of structure-morphologies, from micro-aggregates to a very fine dispersion, probably to the molecular level. In turn, these different morphologies have an influence on the properties of the final systems. Thermal, thermomechanical and mechanical properties have been analysed. The POSS have been shown to change the crosslinking density of the thermosetting networks, while, in thermoplastic systems, the properties of the hybrid systems have been largely influenced by the nature of the organic ligands borne by the POSS
Renotte-Greco, Dominique. "Création et caractérisations de nouveaux ensimages greffés sur supports silices et fibres de carbone." Pau, 1992. http://www.theses.fr/1992PAUU3008.
Full textChan, Yannie Ka Yan. "Evaporation-induced 3-dimensional diblock copolymer micelles micropattern : applications as templated polymeric microwells for cell culture scaffold, bioanalytic arrays and micro-silver networks /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?BIEN%202004%20CHAN.
Full textIncludes bibliographical references (leaves 122-133). Also available in electronic version. Access restricted to campus users.
Douadi-Masrouki, Siham. "Synthèse et caractérisation de films composites dopés par des nanoparticules magnétiques." Paris 6, 2007. http://www.theses.fr/2007PA066197.
Full textMiles, Alexander, Yue Gai, Palash Gangopadhyay, Xinyu Wang, Robert A. Norwood, and James J. Watkins. "Improving Faraday rotation performance with block copolymer and FePt nanoparticle magneto-optical composite." OPTICAL SOC AMER, 2017. http://hdl.handle.net/10150/624970.
Full textRaman, Vinay. "Computational study of self-assembly in block copolymer/superparamagnetic nanoparticle composites under external magnetic fields." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/87530.
Full textCataloged from PDF version of thesis.
Includes bibliographical references.
This computational and theoretical study investigates the self-assembly of superparamagnetic nanoparticles and block copolymers under external magnetic fields. A variety of morphological transitions are observed based on the field orientation, nanoparticle loading, and selectivity of the nanoparticles for the blocks. For symmetric block copolymers, chaining of superparamagnetic nanoparticles under in-plane magnetic fields is shown to achieve long range orientational order of the block copolymer nanodomains and is found to be dependent on nanoparticle size, volume fraction and magnetization strength. A critical selectivity of the particles for one nanodomain is observed, above which strong alignment results and below which comparatively disordered structures are formed. Higher magnetization strengths are found to reduce equilibrium defect densities in the nematic-isotropic ordering of lamellar thin films, as corroborated by scaling arguments. For asymmetric coil fractions forming hexagonal block copolymer nanostructure, the inplane field induced chaining of the nanoparticles selective for the minority block, leads to the formation of stripe phases oriented parallel to the magnetic field. Furthermore, in-plane field induced chaining of nanoparticles selective for the majority block leads to alignment of hexagonal morphology with <100> direction oriented parallel to the external magnetic field. Out of plane magnetic fields induce repulsive dipolar interactions between the nanoparticles that annihilate the defects in the hexagonal morphology of the block copolymer when the nanoparticle is selective for the minority block. Honeycomb lattices are obtained using nanoparticles selective for majority block under out of plane magnetic fields for certain specific nanoparticle loadings. Commensurability of nanoparticle size and loadings with the block copolymer structure is critical in optimizing the ordering of the final composite. Kinetics of alignment in block copolymer nanocomposites is studied using External Potential Dynamics (EPD) method, wherein an equivalent evolution equation for potential fields is solved instead of conservation equation for the monomer segments. The dynamics study reveals an interesting interplay of nanoparticle mobility, dipolar interaction strength and nanoparticle-polymer interaction strength on the rate of alignment of domains.
by Vinay Raman.
Ph. D.
KAIRALLA, ELENI C. "Estudo de hidroxiapatitas revestidas com poli('epsolon'-caprolactona) estrela: processamento e avalição biológica." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23510.
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Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Duaux, Gabriel. "Polymères biosourcés issus de LTTM {glucide polyacide carboxylique eau} : Élaboration et applications dans les matériaux carbonés réfractaires." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI119.
Full textRefractory carbon/carbon composite materials consist of carbonaceous granular fillers shaped with a carbonisable binder. Until now, the binder used has generally been coal tar pitch, which is carcinogenic and covered by REACH. In order to replace it with a product that is more respectful of the environment and of the health of handlers, we are proposing an innovative solution in this thesis work. Carbohydrates, and more particularly sugars, are carbonisable compounds with a low carbon yield. In the presence of polycarboxylic acid, they can form a low transition temperature mixtures characterised by a eutectic or a lower flow temperature than that of its constituents taken separately. This type of mixture is capable of reacting at temperatures of the order of 100°C, thus lower than those commonly required for esterification reactions. This behaviour is similar to that already described for BADES (Brønsted Acidic Deep Eutectic Solvent). Under these conditions, linear and branched (ester-co-oside) copolymers are obtained which lead to a poly(ester-co-oside) network by continuing the reaction under vacuum. By choosing the constituents and controlling the reaction time, it is possible to control the viscosity of the polymers for use as a binder in carbon/carbon composites with granular fillers. In this case, we have shown that the use of polycarboxylic acids has three advantages: i) when mixed with sugars, LTTMs (Low Transition Temperature Mixtures) that are liquid at room temperature are formed, which facilitates their use in the process, ii) they act as a reagent and catalyst for the polymerisation of sugars and iii) they make it possible to increase the carbon yield of the binders. These results are very promising for the manufacture of refractory carbon/carbon composites as an electrode for alumina electrolysis
D'Agosto, Franck. "Synthèse de polymères multifonctionnels à architecture contrôlée pour l'immobilisation de sondes nucléiques." Lyon 1, 2000. http://www.theses.fr/2000LYO10177.
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