La mutation de nos activités industrielles vers le développement durable est l’un des plus gros enjeux humains du 21ème siècle. L’utilisation de la biomasse dans divers domaines tels que l’énergie, la construction et les matériaux est une réponse face à la raréfaction des ressources fossiles et face aux risques écologiques. Les objectifs de cette thèse sont de créer de nouveaux matériaux les plus bio-sourcés possibles et d’optimiser les propriétés de ces matériaux en vue d’une éventuelle utilisation industrielle. Les travaux présentés ici traitent de la fabrication de matériaux composites à renforts de fibres naturelles, ayant pour matrice des résines bio-sourcées. Les ressources végétales principalement étudiées ici sont les tannins, utilisés pour la réalisation de : - Composites à matrice tannin – hexamine - Composites à matrice tannin – résorcine – aldéhyde Les tannins végétaux ont également été étudiés pour la conception de bio-plastiques tannin – alcool furfurylique pouvant être appliqués à la fabrication de composites. Les panneaux composites ont été réalisés en laboratoire et analysés mécaniquement en se basant sur des méthodes normatives européennes. Les résines ont également été caractérisées à l’aide de diverses techniques telles que l’analyse thermomécanique (TMA) ou la spectroscopie de masse MALDI-ToF. Au final, ces travaux ont permis de réaliser des matériaux composites hautement bio-sourcés, aux propriétés homogènes et reproductibles satisfaisant en outre les exigences d’emploi de plusieurs normes européennes / Changing our industrial activities towards sustainable development is one of the major human concerns of the 21th century. The use of biomass in various areas like energy, construction and materials is an answer to the future scarcity of fossil resources and to the ecological risks. The objectives of this thesis are to create new materials with the highest bio-based content possible and then to optimize these materials properties for a potential industrial use. The work presented here is about the fabrication of composite materials reinforced with natural fibers, using bio-based resins as a matrix. The main vegetable resources studied here are tannins, used to make: - Tannin – hexamine matrix composites - Tannin – resorcinol – aldehyde matrix composites Vegetable tannins were also studied to prepare tannin – furfuryl alcohol bio-plastics that may be used in the composites fabrication. The composites boards were made in laboratory and mechanically analyzed based on European norms methods. Resins were also characterized using various techniques such as thermomechanical analysis (TMA) or MALDI-ToF mass spectrometry. The end results of this work is the fabrication of highly bio-based composite materials, with homogenous and repeatable properties that furthermore satisfy several European norms requirements.

La gestion des déchets constitue un problème majeur au niveau mondial. En agriculture, le retour au sol des résidus de culture est une pratique courante et constitue une opportunité intéressante pour maintenir la fertilité du sol et/ou pour stocker du carbone. La décomposition des matières végétales dans le sol est influencée par plusieurs facteurs (tels que la composition microbienne, la nature et qualité des matières végétales), et a pour acteurs principaux les microorganismes telluriques. Au-delà du retour au sol, d’autres voies de valorisation de la matière végétale non récoltée peuvent être envisagées, telle que sa transformation pour des usages non alimentaires. Dans le domaine du bâtiment, l’intérêt de l’utilisation de matériaux biosourcés (destinés à l’isolation thermique) est croissant et encouragé par les pouvoirs publics dans la construction ou la rénovation. Toutefois, à notre connaissance, la question de la gestion de la fin de vie de ces matériaux après déconstruction des bâtiments n’est pas encore abordée. Afin de mieux comprendre le retour aux sols agricoles de matières végétales de natures diversifiées (paille de blé, paille de colza et tiges de tournesol), nous avons combiné différentes caractérisations biochimiques/physicochimiques tels que le fractionnement biochimique, l’analyse thermogravimétrique et la spectroscopie infra rouge, avec l’étude de la dynamique microbienne (abondance, diversité, fonction), complétées du suivi de minéralisation du carbone et de l’azote durant 3 mois d’incubation, en microcosmes. La minéralisation des résidus de grandes cultures est principalement régie par des microbiodiversités initialement différentes, issues de la prairie permanente ou la grande culture, et dans une moindre mesure par leur qualité biochimique. Quant à la dynamique microbienne, elle est impactée par ces deux types de sols et la nature de apports. Dans le cas de coproduits contrastés de la tige de tournesol (moelle et écorce), la minéralisation du C est principalement dictée par leur qualité initiale. Concernant la mise en oeuvre d’un matériau biosourcé à base de moelle de tige de tournesol, elle semble favoriser sa minéralisation dans le sol. Le retour au sol de ce type de matériau pourrait donc constituer un moyen intéressant de gestion de sa fin de vie. / Waste management is a major problem worldwide. In agriculture, the return of crop residues to the soil is a common practice and represents an interesting opportunity to maintain soil fertility and / or to store carbon. The decomposition of plant materials in soils is influenced by several factors (such as microbial composition, plant material’s nature and quality), and soil microorganisms are its main actors. Moreover, other ways of valorization of non-harvested plant materials are possible, such as their transformation for non-food applications. In the building industry, the interest in using biobased materials (for thermal insulation) is growing and encouraged by the public authorities in construction or renovation projects. However, to our knowledge, the issue of management of these materials end-of-life is not yet addressed, after deconstructing the buildings. In order to better understand different crop residues (wheat straw, rapeseed straw and sunflower stems) decomposition in agricultural soils, we have combined different biochemical / physicochemical characterizations such as biochemical fractionation, thermogravimetric analysis and infrared spectroscopy, with microbial dynamics monitoring (abundance, diversity, function), supplemented by carbon and nitrogen mineralization measures during 3 months incubation in microcosms. Crop residues mineralization is mainly governed by initially different microbiodiversities (derived from permanent grassland or conventional cropping system), and to a lesser extent by their biochemical quality. However, microbial dynamics are influenced by both, types of soils and nature of inputs. As for the sunflower stem coproducts (pith and bark), C mineralization is mainly dictated by their initial quality. Concerning the manufacturing process of a sunflower pith biobased material, it seems to favor its mineralization in soil. The return of this type of material to soil could thus constitute an interesting means of managing its end-of-life.

Tesis por compendio / [ES] El aprovechamiento de subproductos para producir biocombustibles, energía y compuestos químicos básicos es cada vez más necesario en la situación actual de escasez de petróleo y preocupación por el medioambiente. Muchos compuestos que tradicionalmente han sido producidos a partir del petróleo pueden sintetizarse hoy día de forma biotecnológica empleando recursos renovables. En este contexto, los microorganismos pueden aprovecharse eficazmente como biocatalizadores para llevar a cabo estas transformaciones. Con este tipo de procesos se pueden aprovechar residuos o materias primas renovables para la obtención de productos de interés como bioplásticos de origen microbiano o productos químicos que pueden servir como monómeros para la síntesis de plásticos biodegradables u otro tipo de aplicaciones. La contaminación ambiental causada por los residuos de polímeros sintéticos no biodegradables es un problema en aumento debido a la estabilidad de los compuestos derivados de los combustibles fósiles. En contraste, los bioplásticos pueden obtenerse de fuentes renovables, lo que posibilita el desarrollo de procesos de producción sostenible. En este trabajo de investigación se han estudiado y desarrollado bioprocesos para la producción de polihidroxialkanoatos, 2,3-butanodiol y ácido D-láctico de forma sostenible empleando materias primas renovables como el suero lácteo de quesería, aceite de camelina, glicerina, fracción orgánica de residuos urbanos y residuos de naranja. La caracterización de las materias primas de partida se realizó mediante técnicas de análisis composicional, análisis en HPLC, cromatografía de gases y técnicas espectrofotométricas. Con estos resultados se hizo una selección de cepas bacterianas capaces de sintetizar los productos de interés a partir de los sustratos seleccionados. Una vez seleccionadas las cepas, el trabajo se centró en el desarrollo de los procesos para conseguir buenos rendimientos de fermentación y su escalado. Por lo tanto, este trabajo de investigación aporta conocimientos sobre la identificación y selección de biocatalizadores industriales para el uso de materias primas renovables y residuos industriales para la producción de productos químicos y polímeros de base biológica. Estos estudios allanan el camino para el futuro desarrollo de procesos biotecnológicos sostenibles en el marco de las biorrefinerías y de la bioeconomía circular. / [CA] L'aprofitament de bioproductes per produir biocombustibles, energia i compostos químics bàsics és cada vegada més necessari en la situació actual d'escassetat de petroli i preocupació pel medi ambient. Molts compostos que tradicionalment s'han produït a partir de petroli es poden sintetitzar hui en dia biotecnològicament utilitzant recursos renovables. En aquest context, els microorganismes es poden utilitzar eficaçment com a biocatalitzadors per dur a terme aquestes transformacions. Amb aquest tipus de processos es poden utilitzar residus o matèries primeres renovables per obtenir productes d'interès com bioplàstics d'origen microbià o químics que puguen servir de monòmers per a la síntesi de plàstics biodegradables o altres aplicacions. La contaminació ambiental causada per residus de polímers sintètics no biodegradables és un problema creixent a causa de l'estabilitat dels compostos de combustibles fòssils. Per contra, els bioplàstics es poden obtenir a partir de fonts renovables, permetent el desenvolupament de processos productius sostenibles. En aquest treball de recerca s'han estudiat i desenvolupat bioprocessos per a la producció de polihidroxialcanoats, 2,3-butanodiol i àcid D-làctic de manera sostenible utilitzant matèries primeres renovables com sèrum de llet, oli de camelina, glicerina, fracció orgànica de residus urbans i residus de taronges. La caracterització de matèries primeres inicials es realitza mitjançant tècniques d'anàlisi composicional, anàlisi HPLC, cromatografia de gasos i tècniques espectrofotomètriques. Amb aquests resultats es crea una selecció de soques bacterianes capaç de sintetitzar els productes d'interès dels substrats seleccionats. Una vegada seleccionades les soques, el treball es va centrar en el desenvolupament dels processos per aconseguir uns bons rendiments de fermentació i el seu escalat. Per tant, aquest treball de recerca aporta coneixements sobre la identificació i selecció de biocatalitzadors industrials per a l'ús de matèries primeres renovables i residus industrials per a la producció de productes químics i polímers de base biològica. Aquests estudis amplien el coneixement per al futur desenvolupament de processos biotecnològics sostenibles en el marc de la biorefineria i la bioeconomia circular. / [EN] The use of by-products to produce biofuels, energy and basic chemicals is increasingly necessary in the current situation of oil shortages and environmental concern. Many compounds that have traditionally been produced from oil can now be synthesised in a biotechnological way using renewable resources. In this context, microorganisms can be effectively used as biocatalysts to carry out these transformations. With this type of process, waste streams or renewable raw materials can be used to obtain products of interest such as bioplastics of microbial origin or chemical products that can serve as monomers for the synthesis of biodegradable plastics or other types of applications. Environmental pollution caused by non-biodegradable synthetic polymer waste is a growing problem due to the stability of compounds derived from fossil fuels. In contrast, bioplastics can be obtained from renewable sources, which enables the development of sustainable production processes. In this research work, bioprocesses for the production of polyhydroxyalkanoates, 2,3-butanediol and D-lactic acid using renewable raw materials such as cheese whey, camelina oil, glycerine, organic waste and orange waste were studied and developed. The characterisation of the raw materials was carried out using compositional analysis, HPLC analysis, gas chromatography and spectrophotometric techniques, among others. With these results, a selection of bacterial strains capable of synthesising the products of interest from the selected substrates was made. Once the strains were selected, the work was focused on process development in order to optimize fermentation yields and scale-up. Therefore, this research work provides knowledge on the identification and selection of industrial biocatalysts for the use of renewable feedstocks and industrial wastes for the production of bio-based chemicals and polymers. These studies pave the way for further development of sustainable biotechnological processes in the framework of biorefineries and circular bioeconomy. / Bustamante Jaramillo, DA. (2021). Production of Bio-Based Chemicals and Polymers from Renewable Feedstocks: Bioprocesses Development [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/175819 / TESIS / Compendio

The need for replacing petroleum-based polymers has been increasing and bio-based polymers prove to be a suitable solution. The aim of this thesis was to synthesize bio-based resins with different chemical architectures to evaluate the effect of the structure on the properties and on their response to ageing and biodegradation. For this, three different bio-based thermoset resins have been synthesised by reacting one of three distinct core-molecules with lactic acid. The options of core-molecules chosen for this work were ethylene glycol, glycerol and pentaerythritol. Lactic acid was first reacted with a core-molecule by direct condensation, the resulting branched molecule was then end-functionalized with methacrylic anhydride. The amount of moles of lactic acid varied according to which core-molecule it was reacted with, but the chain length (n) was always maintained as three. Part of the samples were characterised by Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and tensile test. DSC and TGA were used for determining the thermal behaviour. FT-IR was used to verify the first and second stage of the reaction and to ascertain the occurrence of the crosslinking reaction. Tensile test was done for investigation of mechanical properties. The ageing and biodegradation tests are useful to ascertain the material possible applications. Therefore, the samples that went through the process of ageing or biodegradation were also characterised in the end of the procedures to further check the effect of those processes on the specimens. The test results indicated that the PENTA/LA cured resin was the most stable thermally. The cured resin’s mechanical properties were similar to each other, so there was no comparison to make in this area. The samples proved to be affected by the biodegradation and the ageing processes, both in visual and structural aspects.

The reduction of greenhouse gases in the atmosphere and the transformation from a fossil-based to a bio-based economy are declared social, political and entrepreneurial goals. The efficient material and energetic use of biogenic residues, by-products and wastes offers numerous means of working towards these goals. However, it is still unclear what raw materials can be understood under these collective terms, what quantities exist across sectors and what additional contribution can be expected from their improved use. In the context of this thesis, an internationally applicable method has been developed which can be used to continuously balance and evaluate the technical biomass potential and current use. The basis for this is a modular monitoring system that is used to develop a multi-stage biomass categorisation, a regularly updatable network of biomass-specific calculation elements and a procedure for the continuous improvement of data quality. The monitoring system was tested for a consistent reference year using Germany as an example. In addition, the temporal and spatial dynamics of the biomass availability were analysed for the case study of cereal straw using a geoinformation system. With the help of 1,113 calculation elements, the supply and use of 77 biomasses from five sectors were balanced. On this basis, the technical biomass potential for the year 2015 amounts to 86–140 million tonnes of dry matter. Between 65 % and 84 % are already tied up in a material or energetic use. There is a clear focus on only a few raw materials; 20 % of the resources make up more than 80 % of the supply. By further tapping the mobilisable potential of 14–48 million tonnes of dry matter, an annual primary energy contribution of at least 6 % and up to 15 % could be achieved in future, for example. The detailed analysis for the case study also shows that, despite significant fluctuations over time, large parts of the potential are concentrated in only a few regions. The overall broad ranges of results indicate that the data quality is uncertain and, in particular in the areas of soil and water quality, biodiversity and eutrophication of ecosystems, there is a need for research on how the complex interactions can be integrated into future calculations of biomass potentials, using which data sets. The consequent provision of the monitoring results and calculation methodology in an online data repository (http://webapp.dbfz.de) provides the opportunity to reflect on the existing approaches in an open debate and to continue developing them in line with the respective needs. Using the findings generated by the monitoring system, the focus can be placed on the most important raw materials and regions for the implementation of political and entrepreneurial strategies and for filling gaps in the data. On this basis, the next steps for an optimal and sustainable contribution to a bio-based circular economy can be prioritised and discussed with regional stakeholders and shareholders. / Die Reduktion von Treibhausgasen in der Atmosphäre und die Transformation von einer fossilbasierten zu einer bio-basierten Wirtschaftsweise sind erklärte gesellschaftliche, politische und unternehmerische Ziele. Die effiziente stoffliche und energetische Nutzung von biogenen Reststoffen, Nebenprodukten und Abfällen bietet zahlreiche Möglichkeiten, diesen Zielen näher zu kommen. Unklar ist bisher jedoch, welche Rohstoffe unter diesen Sammelbegriffen verstanden werden können, welche Mengen sektorenübergreifend existieren und welcher zusätzlichentzliche Beitrag aus einer optimierten Nutzung erwartet werden kann. Im Rahmen dieser Arbeit wurde daher eine international anwendbare Methode entwickelt, mit der das technische Biomassepotenzial und die aktuelle Nutzung fortlaufend bilanziert und bewertet werden kann. Die Grundlage bildet hierfür ein modulares Monitoringsystem, mit dem u. a. eine mehrstufige Biomassekategorisierung, ein regelmäßig aktualisierbares Netzwerk aus biomassespezifischen Berechnungselementen sowie ein Vorgehen zur kontinuierlichen Verbesserung der Datenqualität entwickelt wurde. Das Monitoringsystem wurde am Beispiel von Deutschland und für ein konsistentes Bezugsjahr erprobt. Für das Fallbeispiel Getreidestroh wurde darüber hinaus die zeitliche und räumliche Dynamik der Rohstoffverfügbarkeit mit einem Geo-Informationssystem analysiert. Mit Hilfe von 1.113 Berechnungselementen wurden das Aufkommen und die Nutzung für 77 Biomassen aus fünf Sektoren bilanziert. Auf dieser Grundlage ergibt sich für das Jahr 2015 ein technisches Biomassepotenzial in Höhe von 86–140 Millionen Tonnen Trockenmasse. Zwischen 65 % und 84 % waren bereits in einer stofflichen oder energetischen Nutzung gebunden. Ein deutlicher Schwerpunkt liegt auf nur wenigen Rohstoffen; 20 % der Rohstoffe repräsentieren über 80 % des Potenzials. Durch die weitere Erschließung der noch mobilisierbaren Potenziale in Höhe von 14–48 Millionen Tonnen Trockenmasse könnte zukünftig z. B. ein jährlicher Primärenergiebeitrag von mindestens 6 % und bis zu 15 % realisiert werden. Die Detailanalyse für das Fallbeispiel zeigt darüber hinaus, dass trotz erheblicher zeitlicher Schwankungen große Teile des Potenzials in nur wenigen Regionen konzentriert sind. Die insgesamt hohen Ergebnisbandbreiten deuten jedoch auf eine unsichere Datenqualität hin und insbesondere bei den Themen Boden- und Wasserqualität, Biodiversität und Eutrophierung von Ökosystemen besteht Forschungsbedarf, wie und mit welchen Datensätzen die komplexen Wirkungsgefüge zukünftig in die Potenzialberechnungen integriert werden können. Durch die konsequente Offenlegung der Monitoringergebnisse und der Berechnungsmethodik in einem Online-Datenrepositorium (http://webapp.dbfz.de) besteht die Möglichkeit, die bisherigen Ansätze in einem offenen Diskurs zu reflektieren und bedarfsgerecht weiterzuentwickeln. Mit Hilfe der Erkenntnisse aus dem Monitoringsystem kann der Fokus für die Umsetzung von Politik- und Unternehmensstrategien und das Schließen von Datenlücken auf die wichtigsten Rohstoffe und Regionen gelenkt werden. Zusammen mit den regionalen Stake- und Shareholdern können auf dieser Grundlage die nächsten Schritte für einen optimalen und nachhaltigen Beitrag zu einer bio-basierten Kreislaufwirtschaft priorisiert und weiterführend diskutiert werden.

I takt med att fossila resurser begränsas och allmänhetens krav på miljövänliga alternativ ökar, har utvecklingen av biobaserade plaster tagit fart. Nya framsteg i form av fler material, innovativa tillverkningsprocesser och förbättrade egenskaper har gjort att applikationsområdet nu sträcker sig från engångsartiklar med krav på nedbrytbarhet, till tekniska och ingenjörsmässiga applikationer. Syftet med arbetet var att undersöka möjligheterna för företaget Flaxta att använda biobaserade polymerer vid tillverkning av fotbollsbenskydd. Ett klassiskt fotbollsbenskydd består av ett hårdare yttre skal i termoplast tillsammans med en mjukare insida i skumplast. Målet var att identifiera biobaserade polymerer som kan ersätta de fossilbaserade polymerer som idag används vid tillverkning av benskydd för fotbollsspelare. Undersökningen av material utifrån begränsningar på biobaserat innehåll visade att det finns flera biobaserade termoplaster som är identiska med deras konventionella fossilbaserade varianter och direkt kan sättas in i befintliga produktionssystem. Dessa material har goda förutsättningar att ersätta de material som idag används i fotbollsbenskydd. Biobaserade termoplastisk polyuretan (TPU) och polyamid (PA 11) identifierades som de två mest lämpliga termoplasterna för att ersätta befintliga benskyddsmaterial. En övergång till biobaserad TPU skulle kunna minska koldioxidavtrycket vid primärproduktion med 36 % jämfört med fossilbaserad TPU. PA 11 är 100 % biobaserad och släpper ut betydligt mindre koldioxid i atmosfären vid primärproduktion jämfört med flera fossilbaserade polyamider. Undersökningen av biobaserade skummaterial resulterade i att etenvinylacetat (EVA) från företaget Braskem har potentialen att ersätta fossilbaserad EVA och polyuretan (PU) som idag används som mjukt energiabsorberande skummaterial i benskydd på marknaden.  Valet av material tillsammans med benskyddets geometri och design utgör benskyddets skyddande egenskaper. Därför krävs ytterligare tester och analyser av benskydd tillverkade i de biobaserade materialen för att säkerhetsställa att kraven på stötdämpningsförmåga uppnås. / In response to the reduction of fossil resources and increasing public demands for environmentally friendly alternatives, development of bio-based plastics have accelerated. New advancements in the form of more materials, innovative manufacturing processes and improved properties mean that the application area now extends from disposable products with the requirements of biodegradability to products for technical and engineering applications. The purpose of this work was to investigate if the company Flaxta could use bio-based polymers when developing shin guards for football players. A classic shin guard is made out of a thermoplastic outer shell together with a softer inner foam material. The aim was to identify bio-based polymers that could replace fossil-based polymers currently used when developing shin guards.   The study of bio-based materials showed that there are several thermoplastics that are similar to the petrochemical plastics and can be directly inserted into existing production systems. These materials have good potential to be used as environmentally friendly alternatives to the current materials in shin guards. Bio-based thermoplastic polyurethane (TPU) and polyamide (PA 11) were identified as the two most suitable thermoplastics to be used in shin guards. A transition to bio-based TPU could reduce the carbon footprint from primary production by 36% compared to fossil based TPU. PA 11 is 100% bio-based and emits significantly less carbon dioxide in the atmosphere during primary production compared to several fossil-based polyamides, therefore does not contribute as much to climate change. The study of bio-based foam materials showed that ethylene vinyl acetate (EVA) from the company Braskem had the potential to replace the fossil based EVA and polyurethane (PU) which is currently used as soft energy absorbing materials in shin guards on the market.   The choice of material together with the geometry and design make up the protective properties of shin guards. Therefore, further tests and analyzes of shin guards made out of the bio-based materials identified as potential replacements are required to ensure that the standards for shock absorptions are met. / <p>Betyg 2020-07-07</p>

La contamination microbienne des surfaces est l’une des préoccupations majeures des secteurs d’activités comme l’industrie agro-alimentaire, la santé publique et les milieux hospitaliers. Face aux problèmes de santé publique liés à contamination bactérienne sur les surfaces, la préparation de surfaces aux propriétés antibactériennes est devenue un intérêt de recherche majeur pour de nombreux scientifiques et ce, dans de nombreux domaines de recherches. Du point de vue de la chimie, des matériaux et de la microbiologie, la fonctionnalisation des surfaces de matériaux polymères préexistants sans altérer leur propriété initiale est une solution séduisante. Pour cela, développer des nouveaux matériaux antibactériens/antifouling où la surface serait fonctionnalisée par des polymères antimicrobiens, greffés de manière robuste i.e. de façon covalente représente une solution idéale. Afin de faciliter et d’accélérer le processus de criblage, il est proposé dans ce travail une nouvelle approche pour obtenir des polymères ayant des propriétés antimicrobiennes à la fois en solution et à partir de la surface. Ce travail comprend une étude de (co)-polymérisations contrôlées d'esters actifs servant d’intermédiaires pouvant être post-modifiés pour synthétiser des polymères d'intérêts présentant les caractéristiques antimicrobiennes attendues.Ce travail démontre que la polymérisation radicalaire contrôlée en présence de Cu(0)/Cu(II) est une technique appropriée qui permet de préparer facilement des (co)-polymères réactifs, en solution mais aussi à partir de surface de poly (téréphtalate d’éthylène), communément appelé PET. Dans un premier temps, nous aborderons l'étude de la polymérisation contrôlée du méthacrylate de pentafluorophényle (PFPMA), avec son optimisation en solution, puis à partir de surface du PET porteuse de groupement d’amorçage. De plus, la polymérisation du méthacrylate de p-nitrophényle (NPMA) sera également examinée, ainsi que la copolymérisation des deux esters actifs là-encore par polymérisation de type contrôlée en présence de Cu(0)/Cu(II). La post-modification des polymères activés est ensuite présentée. La post-modification s’est révélée efficace et facile à mettre en œuvre. La structure et les caractéristiques des polymères obtenus ont été analysées et confirmées. Il est à noter que la post-modification a pu être effectuée par un processus séquentiel avec une fonctionnalisation simple ou avec plusieurs huiles essentielles, qui possèdent des propriétés naturelles antibactériennes ou antioxydantes. Différents films de PET ont été modifiés, des polymères aux propriétés anti-adhérentes ont été greffés par cette même méthodologie. Ces surfaces modifiées ont été testées contre deux bactéries modèles telles que Staphylococcus aureus et Pseudomonas aeruginosa afin de déterminer si les modifications de surface ont conféré au film de PET les propriétés biologiques attendues. / Microbial contamination on surfaces has become major concern in various areas including industrial process as well as public health and hospitalization. Being aware of several problems causing by adherence and attachment of bacteria on a surface, preparation of antibacterial surface has become a global research interest for researchers in many domains. From the chemistry integrated with material science and microbiology point of view, functionalization of existing polymeric material surfaces is an attractive solution. In this domain, the surface functionalized with covalently grafted antimicrobial polymers represents an ideal solution. In order to facilitate the screening process, it is proposed in this particular research a new approach to obtain polymers with antimicrobial properties both in solution and from surface. The present approach includes a study in controlled (co)polymerization of active ester(s) serving as intermediate templates that can be eventually modified by polymer post-modification process to fabricate polymer of interest with expected antimicrobial characteristics.In general, it is demonstrated herein that the use of Cu(0)-mediated reversible deactivation radical polymerization (RDRP) is a suitable technique that allows facile preparation of reactive (co)polymers in solution and from surface of poly(ethylene terephthalate). First of all, this thesis focused on the study of controlled polymerization of pentafluorophenyl methacrylate (PFPMA) which appeared to be challenging. Furthermore, along with the optimization of polymerization in solution was the investigation of surface-initiated polymerization of this monomer from PET surface. Besides, polymerization of p-nitrophenyl methacrylate (NPMA) and copolymerization of the two active esters by Cu(0)-mediated RDRP were also examined. In addition, polymer post-modification of obtained (co)polymers with various compounds had been proven to be efficient, easy to perform. The structure and characteristics of obtained products were confirmed to match with expectations. It is remarkable that the post-modification can be done as sequential process, single or dual functionalization with several different essential oils, which are natural antibacterial or antioxidant compounds. On the other hand, the success in polymerization and post-modification of polymer of active esters in solution allowed the fabrication of different PET film grafted with polymers that are envisaged to have antiadhesion properties. Attempts to test such properties were also done against two model bacteria including Staphylococcus aureus and Pseudomonas aeruginosa to investigate if expectations are valid.

The incomplete degradation of bio-based and biodegradable plastics (BBPs) in soils causes multiple threats to soil quality, human health, and food security. Plastic residuals can interact with soil microbial communities. We aimed to link the structure and enzyme-mediated functional traits of a microbial community composition that were present during poly (butylene succinate-co-butylene adipate (PBSA) decomposition in soil with (PSN) and without (PS) the addition of nitrogen fertilizer ((NH4 )2SO4 ). We identified bacterial (Achromobacter, Luteimonas, Rhodanobacter, and Lysobacter) and fungal (Fusarium, Chaetomium, Clonostachys, Fusicolla, and Acremonium) taxa that were linked to the activities of ß-glucosidase, chitinase, phosphatase, and lipase in plastic-amended soils. Fungal biomass increased by 1.7 and 4 times in PS and PSN treatment, respectively, as compared to nonplastic amended soil. PBSA significantly changed the relationships between soil properties (C: N ratio, TN, and pH) and microbial community structure; however, the relationships between fungal biomass and soil enzyme activities remained constant. PBSA significantly altered the relationship between fungal biomass and acid phosphatase. We demonstrated that although the soil functions related to nutrient cycling were not negatively affected in PSN treatment, potential negative effects are reasoned by the enrichment of plant pathogens. We concluded that in comparison to fungi, the bacteria demonstrated a broader functional spectrum in the BBP degradation process

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Biobaserade polymerer är en av möjligheterna för att uppnå mer hållbara plaster och produkter. Polyamider (PA) har mångsidiga tillämpningar alltifrån fibrer i kläder till tillämpningar som bildelar. De mest producerade polyamiderna (PA6 och PA66) står för en årlig fossilbränsleförbrukning på nästan 10 miljoner ton. Skadliga effekter berör inte bara produktionsfasen utan även konsumtionsfasen samt hanteringen av uttjänta produkter. Därför är det ett stort behov av att utveckla biobaserade polyamider som är kemiskt återvinningsbara, för att minska miljöpåverkan från dessa material. I detta arbete syntetiserades furanbaserade polyamider (FPA) genom en polykondensationsreaktion mellan hexametylendiamin (HMDA) och en biobaserad disyra, 2,5-furandikarboxylsyra (FDCA). Dessutom framställdes sampolymerer genom att använda olika förhållanden av C6- och C10-diaminer (HMDA och 1,10-dekandiamin). Strukturen och den kemiska sammansättningen av de syntetiserade polymererna och sampolymererna bekräftades med hjälp av Fourier-transform infraröd spektroskopi och kärnresonansspektroskopi. Den högsta molekylvikten som uppnåddes var 9900 g/mol, främst på grund av begränsningar i reaktoruppställningen (avsaknad av ett vakuumsystem och avsaknad av adekvat blandning). Utöver detta identifierades nedbrytningen av FDCA och förångningen av HMDA som potentiella faktorer som hämmade för högre molekylvikt. Baserat på de termiska analyserna visade sig FPA:erna vara amorfa, med en genomsnittlig glastemperatur på 102°C. Vidare visade de syntetiserade polyamiderna hög termisk stabilitet, med en initial nedbrytningstemperatur (motsvarande 5 % viktförlust) på 340°C. / Biobased polymers is one of the pathways to achieve more sustainable plastics and products. Polyamides (PA) are commodity polymers, having versatile applications from fibers in clothes to car parts. The most produced polyamides (PA6 and PA66) account for yearly fossil-fuel consumption of almost 10 million tonnes. The detrimental effects do not only concern the production phase, but also the consumption and end-of-life aspects. Hence, there is a crucial need to develop bio-based polyamides that are chemically recyclable to reduce the environmental impact of these materials.  In this work, furan-based polyamides (FPAs) were synthesized through a polycondensation reaction between hexamethylenediamine (HMDA) and a biobased diacid, 2,5-furandicarboxylic acid (FDCA). In addition, copolymers were made by using different ratios of C6 and C10 diamines (HMDA and 1,10-decanediamine). The structure and chemical composition of the synthesized polymers and copolymers were confirmed using Fourier-transform infrared spectroscopy, and proton nuclear magnetic resonance. The highest molecular weight attained was 9900 g/mol, mainly due to limitations from the reactor setup (absence of a vacuum system and lack of adequate mixing). Adding to this, the degradation of FDCA and the evaporation of HMDA were identified as potential factors inhibiting the increase in molecular weight. Based on the thermal analyses, the FPAs were found to be amorphous, with an average glass transition temperature of 102°C. Further, the synthesized polyamides showed high thermal stability, having an initial degradation temperature (corresponding to 5% weight loss) of 340°C.