Les poly(hydroxyalcanoate)s (PHAs), et notamment les poly(hydroxybutyrate) (PHB) et poly(malolactonate d’alkyle)s (PMLARs), sont des polyesters biosourcés et biodégradables intéressants pour des applications comme polymères de commodité ou dans le domaine médical. La polymérisation par ouverture de cycle (ROP) de β-lactones est une stratégie très efficace pour la synthèse de PHAs, permettant un contrôle de la masse molaire, de la microstructure et de la fonctionnalité des polymères. Ainsi, il s’agit de moduler ces paramètres pour optimiser les propriétés physico-chimiques des polymères. Cette approche a permis de synthétiser de nouveaux (co)polymères PHAs, présentant des fonctionnalités, des tacticités (atactiques, syndiotactiques) et des topologies (copolymères à blocs, aléatoires et alternés) originales. L’utilisation de différents systèmes catalytiques et amorçants a permis la synthèse de PHAs α-base, ω-crotonate téléchéliques atactiques, mais également des premiers exemples de PMLARs (R = allyle, benzyle et méthyle) syndiotactiques. De la même manière, l’ingénierie catalytique offre la synthèse de copolymères P(BL-b-MLABe) et P(BL-ran-MLABe) par copolymérisation séquentielle et simultanée du couple rac-BL/rac-MLABe. Enfin la copolymérisation simultanée des comonomères (R)-MLAAll/(S)-MLABe en présence de complexe d’yttrium a conduit à la synthèse de copolymères alternés P(MLABe-alt-PMLAAll). Leur modification chimique post-polymérisation ouvre la voie à la synthèse de PHAs portant des fonctions latérales réactives alternées. / Biobased and biodegradable polyesters of the family of poly(hydroxyalkanoate)s (PHAs), and more specifically poly(hydroxybutyrate) (PHB) and poly(alkyl malolactonate)s (PMLARs), display a wide array of valuable uses ranging from commodity plastics to biomedical applications. Ring-opening polymerization (ROP) of β-lactones is an efficient strategy for the synthesis of PHAs with control of the molar mass, the microstructure and the functionalities of polymers. So, it is a question of modulating these parameters to optimize the physicochemical properties of polymers. This approach allowed the synthesis of new (co)polymers PHAs, exhibiting original functionalities, tacticities (atactic, syndiotactic) and topologies (block, random and alternating copolymers). Tunable catalytic/initiating systems afford the synthesis of α-base, ω-crotonate telechelic atactic PHAs and of the first examples of syndiotactic PMLARs (R = allyl, benzyl and methyl). Similarly, catalytic engineering offers the synthesis of P(BL-b-MLABe) and P(BL-ran-MLABe) copolymers from the simultaneous and sequential copolymerization of the comonomers rac-BL/rac-MLABe. Finally, simultaneous copolymerization of the comonomers (R)-MLAAll/(S)-MLABe, in the presence of yttrium complexes, leads to the synthesis of alternating copolymers P(MLABe-alt-PMLAAll). Further post-polymerization modifications of these copolymers foresee a route towards a new class of functionalized alternating PHAs.

Ce travail avait pour but de synthétiser et caractériser des copolymères amphiphiles à base de poly(éthylène glycol) (PEG) et de poly(acide lactique) (PLA) pour la confection de systèmes de délivrance de principes actifs (PA). Les polymères ont été choisis pour leur biocompatibilité et de leur biorésorbabilité. Plusieurs architectures de copolymères amphiphiles ont été créées et leur comportement auto-associatif en milieu aqueux ainsi que leur capacité à encapsuler des principes actifs ont été étudiés. Tout d'abord, un copolymère greffé a été synthétisé par copolymérisation d'un monomère fonctionnel, le glycolide monopropargylé, avec du L-lactide pour obtenir un squelette polyester fonctionnel sur lequel des branches hydrophiles de PEG ont été greffés avec plusieurs degrés de substitution. Ensuite, un copolymère peigne tribloc a été synthétisé à partir d'un bloc central PLA dont les extrémités de chaînes ont été modifiées pour permettre l'amorçage de la polymérisation de méthacrylate d'oligo(éthylène glycol) avec des taux de substitution variables. L'étude de l'auto-assemblage et de la capacité à encapsuler des PA a révélé que l'architecture et la balance hydrophile/hydrophobe sont des facteurs déterminants pour la nature des objets formés et leur potentiel d'encapsulation. Enfin, des stratégies de fonctionnalisation ont été mises en place afin d'augmenter et de moduler l'efficacité des PA encapsulés. Ceci est illustré par le couplage d'une molécule fluorescente modèle et, dans le cadre d'une collaboration, par la conjugaison d'un peptide immunostimulateur sur un système dibloc amphiphile. La comparaison à d'autres formulations a montré que le conjugué permettait de moduler et renforcer l'efficacité du PA utilisé. / The objective of this work was to synthesize and characterize amphiphilic copolymers based on poly(ethylene glycol) (PEG) and poly(lactic acid) (PLA) intended for drug delivery applications. The polymers were chosen regarding to their biocompatibility and bioresorbability. Different architectures of amphiphilic copolymers were prepared, and their behavior in aqueous media, as well as their abilities to encapsulate drugs were studied. First, a graft copolymer was synthesized through copolymerization of a functional monomer, monopropargylated glycolide, with L-lactide to yield a functionalized polyester backbone. The latter was then grafted with different densities of hydrophilic branches of PEG. Then, a brush-like triblock copolymer was synthesized through ROP and ATRP. To this end, chain ends of a telechelic block of PLA were modified to yield a macroinitiator able to initiate oligo(ethylene glycol) methacrylate polymerization with variable substitution degrees. Self-assembly and drug loading studies revealed that architecture and hydrophobic/hydrophilic balance played a major role on the nature of the formed objects and on their encapsulation potential. Finally, to modulate and increase the efficacy of encapsulated drugs, functionalization strategies were realized. This is illustrated by the linking of a fluorescent model molecule on a triblock brush-like copolymer and, in a collaboration project, the linking of an immunostimulant peptide on an amphiphilic diblock system. Comparison with other formulations revealed that the conjugate allowed modulating and reinforcing the drug's efficacy.

Textilindustrin är den mest förorenande industrin efter oljeindustrin och ett mål är därför att arbeta med mer återvunna fibrer. Dock väljs ofta dessa alternativ bort av konsumenter även fast en viss efterfrågan har identifierats. Trots en ökad efterfrågan kopplat till hållbara val så besitter inte konsumenter kunskap kring miljöfrågor kopplade till de hållbara alternativen. Avsaknad av kunskap kan alltså vara en orsak till varför deras åsikter inte återspeglas i konsumtionsvalet, därmed uppstår frågan om det finns ett samband mellan kunskap och köpintentioner, eller vilka variabler som påverkar köpintentioner. Polyester är ett material som är mycket påfrestande för miljön och fortsätter vara populärt att använda. Detta har lett till föroreningar, ett avsevärt ökat utsläpp samt stora mängder PET-avfall till miljön. Produktionen av återvunnen polyester, rPET, är mer miljövänlig än produktion av nyproducerad polyester. Exempelvis, för varje kilo mekanisk återvunnen polyester minskar utsläpp av växthusgaser med 70% jämfört med växthusgasutsläpp orsakade av nyproducerad polyester. Då tidigare studier som använt sig av en omarbetad version av teorin Theory of Planned Behavior har visat att attityder, subjektiva normer, upplevd beteendekontroll samt kunskap påverkar intentioner testar denna studie om så även är fallet när de kommer till köpintentioner till rPET. Genom en kvantitativ enkätundersökning och med hjälp av en omarbetad version av teorin Theory of Planned Behavior undersöks om det finns ett samband mellan modellens variabler och köpintentioner till rPET. Resultatet visar att attityder och upplevd beteendekontroll har ett starkt samband med köpintentioner till rPET samt att det finns ett samband, dock negativt och svagare, mellan objektiv kunskap och köpintentioner till rPET. De andra variablerna, subjektiva normer och subjektiv kunskap, besitter inte ett signifikant samband med köpintentioner till rPET. Fortsättningsvis skiljde sig sambanden för variablerna mellan män och kvinnor. / The textile industry is the most polluting industry after the oil industry. Therefore, a goal is to work with more recycled fibers within the textile industry. However, these alternatives are often opted out by consumers despite the fact that a demand has been identified on the market. Previous studies have shown that even though the increased demand is associated with sustainable choices, consumers do not possess knowledge about the environmental issues related to sustainable alternatives. Lack of knowledge can be a reason for why consumers' opinions do not reflect on their consumption choices, hence the question arises whether there is a connection between knowledge and purchase intentions, or which variables do affect the purchase intention. Polyester has a negative impact on the environment but remains popular to use. This has led to pollution, significant increase of emissions, and large amounts of PET waste. The production of recycled polyester, rPET, is however more environmentally friendly than the one of newly produced polyester. For instance, for every kilogram of mechanically recycled polyester, the greenhouse gas emissions are reduced by 70% compared to the greenhouse gas emissions caused by newly produced polyester. By using the revised model Theory of Planned Behavior, previous studies have shown that attitudes, subjective norms, perceived behavioral control and knowledge affects intentions. Thus, this study aims to test whether this is the case or not when it comes to purchasing intention for rPET. By using a quantitative survey and a revised version of the model Theory of Planned Behavior, the revised model explores whether there is a relation between these variables and purchasing intentions towards rPET. The results show that attitudes and perceived behavioral control have a strong relation with purchasing intentions to rPET. Moreover, there is a relation, although negative and weaker, between objective knowledge and purchasing intentions to rPET. However the other variables, subjective norms and subjective knowledge, do not have a significant relation with purchasing intentions to rPET. Furthermore, the relation between the variables differ between the genders.

In the last two decades, hyperbranched (hb) polymers have drawn much attention and obtained intensive research activities both from industry and academia. They are known to have unique and interesting properties which derive from their three dimensional structure and the large number of functional groups. These structural characteristics provide high possibilities for controlling functional group interactions and modifications of other polymers in blends and therefore, they are expected to result in novel materials with desired properties. Furthermore, the easy synthetic accessibility of hb polymers by one-pot synthesis is advantageous as well and allows easy scale-up of laboratory reactions. Having the characteristics as mentioned above, hb polymers are considered good candidates for blend components or melt processing modifiers. In fact, hb polymers have already been used as blend components or additives aiming for different effects. In many cases, reduced viscosity and formation of miscible blends were observed by modification of a linear matrix polymer with hb polymers. More information will be introduced in the following theoretical section. In this work two hb polyester systems based on AB2 and A2+B3 approaches were synthesized and studied. Their possible applications as additives in the blends of linear polyamides were investigated.

Ce travail de thèse concerne l’élaboration et l’optimisation d’un procédé de synthèse par extrusion réactive de polyesters aliphatiques par polycondensation de l’acide sébacique avec le 1,6-hexanediol. L’utilisation des polyesters est un secteur en constante augmentation depuis ces dernières années notamment avec l’utilisation du poly(éthylène téréphtalate) dans des applications d’emballages. Cependant, la synthèse de ces polymères est basée sur des réactions de polycondensations dont les cinétiques sont classiquement assez lentes ce qui entraîne des durées de synthèse longues et in fine assez couteuses. Le but de cette étude est la mise en place d’un procédé continu par extrusion réactive qui permettrait de réduire les durées de synthèse (moins d’une heure) et d'obtenir de hautes masses molaires compétitifs. Dans un premier temps, l’étude porte sur la synthèse en réacteur d’un polyester dît modèle : le poly(hexaméthylène sébaçate). La détermination des conditions optimales de synthèse de ce polyester en réacteur permet de mettre à jour les catalyseurs et leur quantité nécessaire pour obtenir de hautes masses molaires. Une deuxième partie de ce travail de thèse a ensuite été basé sur le transfert des connaissances acquises en réacteur au procédé d'extrusion réactive. Enfin, l’optimisation de l’ensemble des paramètres de la synthèse du polyester modèle et des conditions d’extrusion (profil de vis, profil de température, vitesse des vis…) a permis la synthèse de poly(hexaméthylène sébaçate) dont les masses molaires sont très proches de celles obtenues en réacteur et qui laisse entrevoir un développement très prochain de ce nouveau procédé au niveau industriel. / This PhD thesis is about a new way to synthesis aliphatic polyesters based on hexanediol and sebacic acid by making use of reactive extrusion. Polyesters use have increased each year from the last fifty years, especially the poly(ethylene terephthalate) (PET) for packaging applications. However, polyesters are made from polycondensations, chemical reactions that require a lot of time to obtain high molar mass. The goal of this study is to create and optimise a new synthesis process by reactive extrusion to reduce drastically the synthesis time from several hours to a couple of minutes to obtain the same polyester than the classical process. This thesis is split into two big parts. The first one is the optimisation of the synthesis of the polyester used for the study: the poly(hexamethylene sebacate). Catalysts and synthesis conditions are discussed to draw the scheme of the synthesis in the classical process making used of batch reactors. The second step is the transposition of the synthesis to reactive extrusion. Optimisations of all extrusion conditions (screw profile, temperature range, screw speed…) are performed to obtain a poly(hexamethylene sebacate) with molar mass close to the ones made by batch reactor. This new process make the development of new polyesters faster than before and will allow some new materials based on these polymers.

No description available.

Um tipo de composto têxtil, comumente chamado de membrana têxtil, tem sido empregado, nas últimas décadas, como parte de um sistema arquitetônico usado para a cobertura, fechamento e/ou proteção de espaços públicos e privados em vários países do mundo. O termo membrana está relacionado com o fato de o material permanecer tensionado e separar dois ambientes que se interagem. Essa solução arquitetônica é comumente conhecida como arquitetura têxtil, especialmente quando se trata de estruturas tensionadas; o termo é usado por muitos profissionais em todo mundo, apesar de não existir uma unanimidade de opiniões sobre os conceitos envolvidos na definição do termo e o que ele abrange. Na maior parte dos casos, as obras geradas são muito atraentes, práticas e funcionais, com características, formas e tamanhos diversos, dependendo da necessidade a ser atendida. Quando bem projetadas, integram-se perfeitamente ao ambiente por terem formas orgânicas e passarem uma imagem de leveza, fluidez e modernidade. São dois os tipos de membranas têxteis mais usados: 1) um grupo de membranas cujo tecido estruturante é um tecido de poliéster recoberto em ambos os lados por uma camada de cloreto de polivinila (PVC), e 2) um grupo de membranas feitas com tecidos de vidro recobertos com politetraflúoretileno (PTFE). O foco principal deste trabalho são as membranas de poliéster/PVC usadas para estruturas tensionadas. Os tecidos usados nessa gama estão enquadrados na categoria denominada tecidos técnicos, e são formados por fios compostos por filamentos de poliéster de alta tenacidade de diferentes tipos, gerando vários artigos com características técnicas distintas e, consequentemente, membranas com diversas especificações e comportamentos diferentes na aplicação final.Este estudo traz uma visão geral sobre o assunto no mundo e um panorama mais detalhado para o Brasil, abordando definições, termos usados, materiais, fornecedores, especificações, tipos de produtos e acabamentos, normas, reciclagem e meio ambiente. A beleza e modernidade são apontadas como as principais qualidades desse tipo de cobertura. As expectativas são de crescimento dessa aplicação para os próximos anos. Porém a falta de conhecimento e a complexidade técnica desse tipo de solução é um problema a ser solucionado para que melhores resultados sejam atingidos e ela possa realmente ser considerada uma solução viável e adequada para o país. / The type of textile compound, commonly called textile membrane, has been employed in recent decades, as part of an architectural system used for covering, closing and/or protection of publics and private spaces in many countries around the world. The term membrane is related to the fact that the material remains tensioned and separating two interacting environments. This architectural solution is commonly known as \' textile architecture \', especially when tensile structures are involved; this term is used by many professionals worldwide, although it do not exist a unanimity of opinions regarding the concepts involved in the definition of the term and what it encompasses. In most cases, the structures generated are very attractive, practical and functional, with different characteristics, different shapes and sizes, depending on the requirements to be met. When well designed, they will be seamlessly integrated with the environment by having organic forms, giving a feeling of lightness, fluidity and modernity. The two types of textile membranes commonly used are: 1) a group whose structuring material of the membrane is a polyester fabric coated, on both sides, with a layer of polyvinyl chloride (PVC), and 2) a group of membranes made with glass filament fabrics coated with polytetrafluoretilene (PTFE). The focus of this work is the polyester/PVC membranes used for tensile structures. The fabric used in this range is framed within the category named \'technical fabrics\', and are composed by different kinds of high tenacity yarns of polyester filaments, generating several articles with different technical characteristics and consequently, membranes with different specifications and different behaviors in the final application. The study provides an overview of the subject in the world and a panorama slightly more detailed for Brazil, covering definitions, terms, used materials, suppliers, specifications, product types and finishes, recycling and environment issues. The \' beauty \' and \' modernity \' are cited as the main qualities of this type of covering. There are expectations of growing of this application for coming years. But the lack of knowledge and the technical complexity of this kind of solution is a problem to be solved, so that best results can are achieved and it can really be considered a viable and appropriate solution for the country.

Um tipo de composto têxtil, comumente chamado de membrana têxtil, tem sido empregado, nas últimas décadas, como parte de um sistema arquitetônico usado para a cobertura, fechamento e/ou proteção de espaços públicos e privados em vários países do mundo. O termo membrana está relacionado com o fato de o material permanecer tensionado e separar dois ambientes que se interagem. Essa solução arquitetônica é comumente conhecida como arquitetura têxtil, especialmente quando se trata de estruturas tensionadas; o termo é usado por muitos profissionais em todo mundo, apesar de não existir uma unanimidade de opiniões sobre os conceitos envolvidos na definição do termo e o que ele abrange. Na maior parte dos casos, as obras geradas são muito atraentes, práticas e funcionais, com características, formas e tamanhos diversos, dependendo da necessidade a ser atendida. Quando bem projetadas, integram-se perfeitamente ao ambiente por terem formas orgânicas e passarem uma imagem de leveza, fluidez e modernidade. São dois os tipos de membranas têxteis mais usados: 1) um grupo de membranas cujo tecido estruturante é um tecido de poliéster recoberto em ambos os lados por uma camada de cloreto de polivinila (PVC), e 2) um grupo de membranas feitas com tecidos de vidro recobertos com politetraflúoretileno (PTFE). O foco principal deste trabalho são as membranas de poliéster/PVC usadas para estruturas tensionadas. Os tecidos usados nessa gama estão enquadrados na categoria denominada tecidos técnicos, e são formados por fios compostos por filamentos de poliéster de alta tenacidade de diferentes tipos, gerando vários artigos com características técnicas distintas e, consequentemente, membranas com diversas especificações e comportamentos diferentes na aplicação final.Este estudo traz uma visão geral sobre o assunto no mundo e um panorama mais detalhado para o Brasil, abordando definições, termos usados, materiais, fornecedores, especificações, tipos de produtos e acabamentos, normas, reciclagem e meio ambiente. A beleza e modernidade são apontadas como as principais qualidades desse tipo de cobertura. As expectativas são de crescimento dessa aplicação para os próximos anos. Porém a falta de conhecimento e a complexidade técnica desse tipo de solução é um problema a ser solucionado para que melhores resultados sejam atingidos e ela possa realmente ser considerada uma solução viável e adequada para o país. / The type of textile compound, commonly called textile membrane, has been employed in recent decades, as part of an architectural system used for covering, closing and/or protection of publics and private spaces in many countries around the world. The term membrane is related to the fact that the material remains tensioned and separating two interacting environments. This architectural solution is commonly known as \' textile architecture \', especially when tensile structures are involved; this term is used by many professionals worldwide, although it do not exist a unanimity of opinions regarding the concepts involved in the definition of the term and what it encompasses. In most cases, the structures generated are very attractive, practical and functional, with different characteristics, different shapes and sizes, depending on the requirements to be met. When well designed, they will be seamlessly integrated with the environment by having organic forms, giving a feeling of lightness, fluidity and modernity. The two types of textile membranes commonly used are: 1) a group whose structuring material of the membrane is a polyester fabric coated, on both sides, with a layer of polyvinyl chloride (PVC), and 2) a group of membranes made with glass filament fabrics coated with polytetrafluoretilene (PTFE). The focus of this work is the polyester/PVC membranes used for tensile structures. The fabric used in this range is framed within the category named \'technical fabrics\', and are composed by different kinds of high tenacity yarns of polyester filaments, generating several articles with different technical characteristics and consequently, membranes with different specifications and different behaviors in the final application. The study provides an overview of the subject in the world and a panorama slightly more detailed for Brazil, covering definitions, terms, used materials, suppliers, specifications, product types and finishes, recycling and environment issues. The \' beauty \' and \' modernity \' are cited as the main qualities of this type of covering. There are expectations of growing of this application for coming years. But the lack of knowledge and the technical complexity of this kind of solution is a problem to be solved, so that best results can are achieved and it can really be considered a viable and appropriate solution for the country.

Aerospace research for next-generation travel increasingly focuses on the use of advanced composites to reduce weight and cost while retaining strength. One subset of materials with great potential is based on the combination of resin matrix and glass-fiber reinforcement. This research explores the application of a candidate nanopaper coating with a given composite. Prior research applied a set of given heat fluxes to the top surface of the composite for a set of given periods of time, and subsequently performed a 3-point flexural test to determine the elastic modulus for both the coated and uncoated composite for all of the combinations of heat flux and time. A finite element (FE) model is developed using the ANSYS general purpose finite element analysis (FEA) software that models the degradation in strength/stiffness properties based on heating condition and with the goal of predicting cracking using the element death feature in ANSYS. This thesis describes the prior research suggesting both the need for and novelty of this model, and the procedures used to form the model. The loading conditions of the 3-point flexural test are replicated, and four measures of accuracy are developed based on the force versus displacement curve of the test and the FE model. It is envisioned that continuum-level models developed as a part of these research be applied for design of next-generation space components These measurements are used to verify the FE model, and this model is then employed to extrapolate beyond the context of experimental conditions.

Les poly(3-hydroxyalcanoate)s ou PHAs sont des biopolyesters linéaires biodégradables et biocompatibles synthétisés par des microorganismes bactériens en tant que réserve de carbone et d'énergie. Ils sont synthétisés par des bactéries à partir de ressources renouvelables et la diversité de leurs structures possibles se traduit par un large éventail de polymères ayant des propriétés mécaniques très différentes. Nous avons tout d'abord testé les capacités de production de PHAs de nouvelles souches bactériennes marines provenant de tapis microbiens de Polynésie française, en utilisant, entre autres, des substrats naturels comme l'huile de coprah, le glucose et l'acide oléique. Nous avons notamment montré que la souche Pseudomonas guezennei est capable de produire des PHAs avec des taux d'insaturation contrôlés et de masse molaire très élevée. Puis, des oligomères de PHAs fonctionnalisés de structures contrôlées portant des fonctions terminales alcynes ou alcènes ont été préparés par transestérification. Ces oligomères ont ensuite été utilisés pour l'élaboration par chimie click de copolymères amphiphiles greffés EPS-g-PHA avec des exopolysaccharides (EPS) bactériens. Enfin la dernière partie de ces travaux a consisté en la réalisation d'un support de croissance pour le développement de cellules souches pour l'ingénierie tissulaire combinant les propriétés mécaniques des PHAs et les propriétés hydrophiles et bioactives des EPS / Poly(3-hydroxyalkanoate)s, or PHAs, are linear biodegradable and biocompatible biopolyesters synthesized by bacterial microorganisms as energy and carbon supply. They are synthesized by bacteria from renewable resources and the diversity of the achievable structures leads to a large range of mechanical properties. First, we studied the PHAs production ability of several new marine bacteria strains, isolated from microbial mats from French Polynesia, using, among others, natural substrates such as coprah oil, glucose and oleic acid. We showed particularly that the strain Pseudomonas guezennei was able to produce PHAs with controlled amounts of insaturations and high molar masses. Then, we prepared functionalized PHAs oligomers with controlled structure and bearing a terminal alkyne or alkene function. Following that, these oligomers were used to elaborate amphiphilic by click chemistry graft copolymers EPS-g-PHA with bacterial exopolysaccharide (EPS). Finally, the last part of this work was the making of a scaffold for stem cell culture for tissue engineering which combined the mechanical properties of PHAs and the hydrophilicity and bioactive properties of EPS