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Développement, étude physico-chimique et optimisation de mousses polymères biosourcées / Development, physico-chemical study and optimization of bio-based polymer foamsMazzon, Elena 08 July 2016 (has links)
Ce travail de thèse porte sur le développement d’une nouvelle génération de mousses polymères biosourcées capables de satisfaire la fonction d’âme alvéolaire et structurale de pièces automobiles. Les formulations époxy choisies comme base polymère reposent sur deux différents prépolymères époxy, l’huile de lin époxydée (ELO) et le glycérol époxydé (GE). Ces derniers, associés en proportions variables, sont réticulés avec deux différents durcisseurs : l’isophorone diamine (IPDA) ou l’anhydride méthyl tétrahydrophtalique (MTHPA). Les formulations ternaires « ELO – GE – durcisseur » ont été caractérisées selon une approche multi-techniques (DSC, TGA, rhéométrie dynamique et en mode permanent) permettant d’établir des relations structure-propriétés fiables. Puis, la production d’une mousse a été possible grâce à la maîtrise d’une réaction chimique qui se déroule parallèlement à la réticulation de la résine époxy. Le bicarbonate de sodium et de potassium ont été retenus comme agents moussants. Afin d’améliorer les performances finales des mousses, la proportion de GE au sein des formulations polymère à base IPDA a été augmentée. Mais, une telle modification induit la dégradation thermique du système à cause de l’exothermicité élevée de la réaction de réticulation. L’introduction d’un absorbeur d’exothermicité, permet grâce à sa décomposition endothermique de contrôler l’excès de chaleur dégagée et par la même d’empêcher la dégradation. Une dernière classe de durcisseurs a également été étudiée et donne après optimisation des mousses dotés d’excellentes propriétés ultimes. Ainsi, une large gamme de mousses biosourcées rigides et légères pouvant être mises en œuvre dans un temps très court a été développée. / This thesis focuses on the development of a new generation of bio-based polymer foams able to produce low density core in sandwich structure for automotive applications. The polymer formulations used in this research contain two different epoxy compounds, epoxidized linseed oil (ELO) and the epoxidized glycerol (GE). Combined in varying proportions, they were cured with two different hardeners, isophorone diamine (IPDA) or methyl tetrahydrophthalic anhydride (MTHPA). Ternary formulations “ELO – GE – hardener” were characterized by a multi-techniques approach (DSC, TGA, rheometry in steady or dynamic mode) in order to establish structure-property relationships. The production of polymeric-foam materials was carried out by tuning a chemical reaction which takes place during curing. Sodium bicarbonate and potassium bicarbonate were used as harmless foaming agents. In order to improve the final performances of the foams, the ratio GE/ELO was increased in the reactive formulations based on IPDA hardener. But, such modification provokes also the thermal degradation of the system because of the high exothermicity of the curing reaction. The introduction of “exothermicity regulators” that undergo endothermic transformations allowed to control the excess of released heat and consequently, to prevent the material degradation. A last class of hardener was also studied and made it possible after optimization the production of foams with good ultimate properties. To conclude, a large range of biobased and lightweight rigid foams able to be produced in a few minutes was developed.
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NanobiocompÃsitos superparamagnÃticos para aplicaÃÃo como antenas ressoadoras dielÃtricas / Superparamagnetic nanobiocomposites for application as dielectric resonator antennasAndrà Leandro da Silva 14 August 2014 (has links)
nÃo hà / à crescente o interesse mundial pelo desenvolvimento de tecnologias chamadas âverdesâ que possibilitem o uso de produtos com menor impacto ao meio ambiente, assim como tambÃm se fortalecem as polÃticas de incentivo ao aproveitamento mÃximo e sustentÃvel dos recursos naturais. O principal objetivo desse estudo foi desenvolver nanobiocompÃsitos superparamagnÃticos para aplicaÃÃo como antenas ressoadoras dielÃtricas. Para tal, um plÃstico termorrÃgido biobaseado foi preparado utilizando o cardanol em alternativa aos fenÃis petroquÃmicos. Esse plÃstico termorrÃgido foi utilizado como matriz para o preparo de biocompÃsitos, utilizando 15% em massa de fibra de bucha bruta e tambÃm modificada por tratamento quÃmico (NaOH 5, 10 e 15% e NaClO 1%) como fase dispersa. Para o preparo dos nanobiocompÃsitos, alÃm da fibra de bucha, nanopartÃculas de magnetita, sintetizadas pelo mÃtodo da coprecipitaÃÃo, foram impregnadas no plÃstico termorrÃgido em diferentes teores de 1, 5 e 10% em massa. TÃcnicas de Termogravimetria (TG), Calorimetria exploratÃria diferencial (DSC), AnÃlise dinÃmico-mecÃnica (DMA), Microscopia eletrÃnica de varredura (MEV), Microscopia Ãptica, Microscopia eletrÃnica de transmissÃo (MET), DifraÃÃo de raios X (DRX), Espectroscopia no infravermelho com transformada de Fourier (FTIR), Espectroscopia MÃssbauer, Ensaios de resistÃncia à traÃÃo, Medidas dielÃtricas, Magnetometria de amostra vibrante (VSM) e BiodegradaÃÃo em solo simulado foram utilizadas para caracterizaÃÃo. Os resultados mostraram que o tratamento alcalino melhorou a estabilidade tÃrmica e o Ãndice de cristalinidade da fibra de bucha. O agente reticulador utilizado (DETA) mostrou-se eficiente, possibilitando a cura completa dos materiais. Os biocompÃsitos com fibra tratada apresentaram maior estabilidade tÃrmica, resistÃncia à traÃÃo superior e melhor Ãndice de biodegradaÃÃo em relaÃÃo ao biocompÃsito com fibra natural. A magnetita sintetizada exibiu tamanho nanomÃtrico, alÃm de alta pureza, alta cristalinidade e carÃter superparamagnÃtico. Todos os nanobiocompÃsitos exibiram superparamagnetismo e mostraram excelente estabilidade tÃrmica, boas taxas de biodegradaÃÃo e melhor resistÃncia mecÃnica para o material com 10% de magnetita. Todas as antenas ressoadoras dielÃtricas preparadas apresentaram perda de retorno satisfatÃria e, portanto, adequaÃÃo para fins comerciais e tecnolÃgicos, com maior potencial para atuaÃÃo em banda larga. / There is a growing global interest for the development of green technologies that allow the use of products with less damage to environment, as well as for maximum and sustainable use of natural resources. The main aim of this study was to develop superparamagnetic nanobiocomposites for application as dielectric resonator antennas. For this purpose, a biobased thermoset plastic was prepared by using cardanol as an alternative to petrochemical phenol. This thermoset plastic was used as a polymer matrix and biocomposites were prepared by using 15 wt% of untreated and modified sponge gourd fibers by chemical treatment (NaOH 5, 10, and 15 wt% and NaClO 1 wt%) as dispersed phase. For the nanobiocomposites preparation, besides the sponge gourd fibers insertion, the thermoset plastic were also impregnated with magnetite nanoparticles in different contents (1, 5, and 10 wt%). Techniques of Thermogravimetry (TG), Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA), Scanning Electron Microscopy (SEM), Optical Microscopy, Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), MÃssbauer Spectroscopy, Tensile testing, Dielectric measurements, Vibrating Sample Magnetometry (VSM) and Biodegradation in simulated soil were performed for characterization. The results showed that alkaline treatment improved the thermal stability and the crystallinity index of the sponge gourd fiber. The crosslinking agent used (Diethylenetriamine) was efficient and enabled complete cure for all materials. The biocomposites reinforced by treated fiber showed better thermal stability, superior performance in Tensile testing and greater biodegradation rates, when compared to the biocomposite reinforced by raw fiber. The magnetite particles exhibited nanometric size, high purity and crystallinity, and superparamagnetic character. All nanobiocomposites showed superparamagnetic behavior, excellent thermal stability, good biodegradation rates, and better mechanical strength for the material with magnetite 10 wt%. All dielectric resonators antennas exhibited satisfactory return loss and suitability for commercial and technological applications, especially for performance in broadband.
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Synthèse de macromonomères photopolymérisables de L-lysine biosourcée et leur polymérisation par irradiation UV pour des applications dans le domaine des revêtements / Synthesis of photocurable macromonomers based on biobased L-lysine and their polymerization under UV irradiation for coating applicationsKoleilat, Houria 13 December 2013 (has links)
Les matières premières biosourcées s'avèrent être une possibilité de substitution du pétrole de plus en plus prisée dans le domaine des matériaux. De plus, l'utilisation de procédé propre limitant l'impact environnemental du développement de matériau est aujourd'hui incontournable. Dans ce contexte, l'acide aminé L-lysine, un nouveau synthon issu des biotechnologies blanches peu étudié dans le domaine de la chimie des matériaux, a été retenu. Ce synthon sera modifié pour la conception de macromonomères polymérisables sous irradiation UV. En effet, la technique de photopolymérisation est un procédé propre en plein essor, et qui permet le développement de revêtement.La L-lysine étant peu soluble dans les milieux organiques classiques, une étape de transformation est nécessaire pour améliorer sa processabilité. Ainsi, la polycondensation en masse de la L-lysine a conduit à des oligomères de poly-L-lysine de faibles masses molaires. La détermination de la structure obtenue a été réalisée par différentes techniques d'analyses. Ces oligomères sont alors greffés par des fonctions photopolymérisables dans des conditions douces. Le choix s'est porté sur des fonctions accepteur et donneur d'électron. Enfin, l'étude de la photopolymérisation des oligomères de L-lysine greffés accepteurs donneurs a été effectuée par la technique UV aqueuse, une technique innovante et respectueuse de l'environnement, dans différentes conditions pour en optimiser le système. / Biobased raw materials are an interesting and promising option for the substitution of fossil resources in material design. Moreover, using green processes which limit environmental impact of the material conception can't be avoided nowadays. In this context, the L-lysine amino acid, a building block made by white biotechnologies and poorly described in material field has been evaluated. As photopolymerization is a green process in great expansion and allowing coating design, this building block has been modified into a photocurable macromonomer.L-lysine is hardly soluble in usual organic solvents, a transformation step is necessary in order to improve its processability. Thus, L-lysine polycondensation has been tackled and led to oligomers of poly-L-lysine with low molar mass and improved solubility. In addition, the structure determination has been undertaken by different analytic technics. These oligomers can thus be grafted with photocurable functional groups in mild conditions. The chosen photocurable functional groups are donor acceptor of electron. At last, the photopolymerization of L-lysine based oligomers grafted with donor acceptor functional groups has been done by UV waterborne technic which is innovative and environmentally friendly. The photopolymerization has been carried out in different conditions in order to optimize the process.
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Synthèse, caractérisation et propriétés des oligoesters et composites sulfonés biosourcés / Synthesis, characterization and properties of biobased, sulfonated oligoesters and compositesHadj kacem, Yosra 17 July 2019 (has links)
La transformation de la biomasse végétale en composés simples pouvant servir comme monomères pour l’élaboration de nouveaux matériaux polymères susceptibles de se substituer à leurs homologues d’origine pétrochimique a été l’un des thèmes de recherche développés au cours des deux dernières décennies. c’est dans ce vaste contexte que s’inscrivent les travaux rapportés dans ce mémoire dont l’objectif était d’élaborer une nouvelle famille d’oligoesters aliphatiques en partant de monomères biosourcés et en intégrant dans leur structure des groupes sulfonés. Cette orientation est justifié par les trois considérations suivantes (i) cela constitue une contribution à la valorisation de la biomasse végétale (ii) la présence des unités sulfonés dans leur structure leur confère des propriétés physico-chimiques particulières favorisant leur utilisation dans divers secteurs industriels. (iii) Ces oligoesters peuvent être par la suite utilisés pour la préparation des composites à base de réseaux de poly (ester-uréthane) et de liquide ionique ayant des propriétés thermomécaniques potentiellement intéressantes et une grande tendance à la dégradation hydrolytique. / The research conducted in this thesis was achieved in the context of vegetal biomass valorization. It aims to develop a new family of aliphatic oligoesters from biobased monomers and incorporating into their structure sulfonated groups. This choice is justified by the following three considerations. (i) This is a contribution to the valorization of vegetal biomass. (ii) The presence of sulfonated units in the structure of this type of polymers gives them specific physicochemical properties favoring their use in various industrial sectors. (iii) These oligoesters can be subsequently used for the preparation of poly (ester-urethane) networks and ionic liquid-based composites with potentially interesting thermomechanical properties and a great tendency towards hydrolytic degradation.
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Exploring climate impacts of timber buildings : The effects from including non-traditional aspects in life cycle impact assessmentPeñaloza, Diego January 2015 (has links)
There is an urgency within the building sector to reduce its greenhouse gas emissions and mitigate climate change. An increased proportion of biobased building materials in construction is a potential measure to reduce these emissions. Life cycle assessment (LCA) has often been applied to compare the climate impact from biobased materials with that from e.g. mineral based materials, mostly favouring biobased materials. Contradicting results have however been reported due to differences in methodology, as there is not yet consensus regarding certain aspects. The aim of this thesis is to study the implications from non-traditional practices in climate impact assessment of timber buildings, and to discuss the shortcomings of current practices when assessing such products and comparing them with non-renewable alternatives. The traditional practices for climate impact assessment of biobased materials have been identified, and then applied to a case study of a building with different timber frame designs and an alternative building with a concrete frame. Then, non-traditional practices were explored by calculating climate impact results using alternative methods to handle certain methodological aspects, which have been found relevant for forest products in previous research such as the timing of emissions, biogenic emissions, carbon storage in the products, end-of-life substitution credits, soil carbon disturbances and change in albedo. These alternative practices and their implications were also studied for low-carbon buildings. The use of non-traditional practices can affect the climate impact assessment results of timber buildings, and to some extent the comparison with buildings with lower content of biobased building materials. This effect is especially evident for energy-efficient buildings. Current normal practices tend to account separately for forest-related carbon flows and aspects such as biogenic carbon emissions and sequestration or effects from carbon storage in the products, missing to capture the forest carbon cycle as a whole. Climate neutrality of wood-based construction materials seems like a valid assumption for studies which require methodological simplification, while other aspects such as end-of-life substitution credits, soil carbon disturbances or changes in albedo should be studied carefully due to their potentially high implications and the uncertainties around the methods used to account for them. If forest phenomena are to be included in LCA studies, a robust and complete model of the forest carbon cycle should be used. Another shortcoming is the lack of clear communication of the way some important aspects were handled. / <p>QC 20150310</p>
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Elaboration, caractérisation et mise en œuvre de matériaux polymères à base de polysemicarbazides et polyester furanique bio-sourcés / Elaboration, caracterisation and processing of polymer matérials based on bio-sourced polysemicarbazides and furanic polyestersGhorbel, Inès 15 February 2013 (has links)
Ce travail est développé dans le but d’élaborer, caractériser et mettre en œuvre de matériaux polymères à base de polysemicarbazides et polyesters furaniques bio-sourcés. L’étude comporte trois grandes parties : la synthèse et l’optimisation du procédé de synthèse de poly(acylsemicarbazide)s, la préparation de quelques mélanges de polymères en mini-bivis de polymères furaniques (PEF ou PSC) avec le PET, le PLA et le PHA et l’élaboration de nouveaux copolyesters furano-aliphatiques par polymérisation par ouverture de cycle (PEF/PCL) ou par réactions d’interéchanges à l’état fondu de mélange d’homopolymères (PEF/PCL, PEF/PLA et PEF/PHA). Nous rapportons dans le premier chapitre de ce mémoire la synthèse d’une série de dihydrazides bifuraniques et l’étude de leur réactivité vis-à-vis de divers diisocyanates aromatiques afin d’élaborer des polyacylsemicarbazides furano-aromatiques. Notre étude est abordée en examinant le comportement d’un système de monomères modèle dans différentes conditions expérimentales afin d’optimiser le procédé de polycondensation avant de l’appliquer à diverses combinaisons de monomères. Nous traitons dans le deuxième chapitre l’élaboration de nouveaux matériaux à base de polymères furaniques (PEF ou PSC) par mélange de polyesters à l’état fondu. Pour cela, nous avons élaboré 3 types de mélanges polyester furaniques / polyesters aliphatiques et aromatiques. Enfin, nous nous intéressons dans le troisième chapitre à la synthèse de divers polyesters furaniques à extrémités contrôlées : PEF-dihydroxy (PEF di-OH), PEF-dicarboxylé (PEF di-COOH), PEF-diéthylester (PEF di-COOEt) et PEF à extrémités mixtes (PEF di-OH/COOEt). Ces derniers ont été utilisés pour l’élaboration de nouveaux polyesters furano-aliphatiques par la technique de polymérisation par ouverture de cycle (PEF /PCL) ou suite à des réactions d’interéchange à l’état fondu à partir de mélanges d’homopolymères (PEF/PLA, PEF/PHA et PEF/PCL). / This work aims at elaborating, characterising and processing polymer materials based on bio-sourced polysemicarbazides and furanic polyesters. The study has three main parts : Synthesis and optimisation of the synthesis of poly(acylsemicarbazide)s, elaboration of polymer blends based on furanic polymers (PEF or PSC) with PET, PLA and PHA and elaboration of new furano-aliphatic copolyesters by ring opening polymerisation (PEF/PCL) or by inter-exchange reactions between ’homopolymers (PEF/PCL, PEF/PLA et PEF/PHA) in the melt. The first chapter reports on the synthesis of a serie of bifuranic dihydrazides and on the study of their reactivity with several aromatic diisocyanates in order to elaborate furano-aromatic polyacylsemicarbazides. The behaviour of model monomer systems in various experimental conditions is studied in order to d’optimise the polycondensation processbefore transfering it to several monomer combinations. In the second chapter, we study the elaboration of new materials based on furanic polymers (PEF or PSC) blended with polyesters in the melt. 3 kinds of blends based on furanic polyesters / aliphatic and aromatic polyesters. The third chapter is devoted to the synthesis of furanic polyesters with controlled ends : dihydroxy-PEF (PEF di-OH), dicarboxylate-PEF (PEF di-COOH), diethylester-PEF (PEF di-COOEt) as well as PEF with mixed ends (PEF di-OH/COOEt). The latest have been used for the elaboration of new furano-aliphatic polyesters by ring opening polymerisation (PEF /PCL) or after interexchange reaction in melt homoplymer blends (PEF/PLA, PEF/PHA and PEF/PCL).
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Synthesis and molecular modelling of bio-based polyamides / Synthèse et modélisation moléculaire de polyamides biosourcésCousin, Thibault 19 March 2013 (has links)
Dans le contexte actuel de raréfaction des ressources fossiles, le développement des polymères biosourcés est d'une grande importance. Le travail de cette thèse consiste donc en la synthèse et le développement d'un polyphtalamide amorphe à base d'acide furan-2,5-oique. Dans un premier temps, un protocole de modélisation moléculaire permettant de calculer la Tg de polyphthalamides a été développé. Pour cela, des PPA modèles (basés sur un mélange d'acides isophtaliques et téréphtaliques ainsi que l'hexaméthylène diamine) ont été synthétisés et caractérisés. En comparant les Tg obtenues par modélisation et par mesure en DSC, le protocole de modélisation a été validé. Dans un deuxième temps, ce protocole a été appliqué à des PPA à base de FDCA. Ces polymères ont également été synthétisés et caractérisés. Il en ressort que le PA 6-F subit une importante décarboxylation durant sa synthèse, l’empêchant d'atteindre une masse molaire importante. Il a aussi été montré que l'ajout de FDCA dans des copolyphthalamides diminuait leurs propriétés thermiques et mécaniques. / In the current context of oil resources rarefaction, the development of biobased polymers is of major importance. The present work focused on the development of a biobased amorphous polyphthalamide, based on furan-2,5-dicarboxylic acid. The first part of the study was devoted to the development of a molecular modelling protocol that could calculate the glass transition temperature of polyphthalamides with accuracy. In order to do this, model polyphthalamides based on isophthalic, terephthalic acid and hexamethylene diamine were synthesized and characterized as well as simulated. By comparison between simulated and measured Tg, the protocol was validated. In a second part of the study, this protocol was applied to FDCA based polyphthalamides. These PPA were also synthesized. It was found that the PA 6-F undertakes a decarboxylation, preventing it from reaching high a molar mass. It was also found that the mechanical and thermal properties decrease as the amount of FDCA in the copolymers increases.
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Nouveaux copolymères biosourcés à blocs polytriméthylène éther pour applications cosmétiques / New biobased copolymers with polytrimethylene ether block for cosmetic applicationsRodier, Jean-David 13 September 2016 (has links)
L’objectif du projet est de préparer de nouveaux copolyéthers hydrophiles biosourcés, non ioniques, pour des applications cosmétiques proches de celles du polyéthylène glycol (PEG). Le polytriméthylène éther glycol (PTEG), dont la structure ressemble à celle du PEG, a été synthétisé par polymérisation du 1,3-propanediol biosourcé (PDO) en catalyse acide. Parmi les catalyseurs testés, l’acide sulfurique est le plus approprié pour polymériser le PDO sans dégradation excessive. Pour augmenter la solubilité du PTEG dans l’eau, des copolymères associant des unités PDO et des unités hydrosolubles type isosorbide et glycérol ont été envisagés. Ainsi, nous avons montré que l’éthérification en catalyse acide entre l’isosorbide et le PDO (ou le PTEG) conduit à de nouvelles structures de copolyéthers que nous avons finement caractérisés par RMN et spectrométrie de masse. Ces copolyéthers ont des extrémités préférentiellement constituées d’unités isosorbide, du fait d’un différentiel de réactivité entre le PDO et l’isosorbide. En revanche, l’éthérification du PDO et du glycérol par catalyse à l’acide sulfurique ou par catalyse basique n’a pas abouti. En effet, dans le premier cas, on observe une très forte dégradation voire une réticulation et dans le deuxième cas, seule l’homopolymérisation du glycérol est observée. Pour compléter, la réaction entre du carbonate de glycérol et un oligomère de PTEG donne les dérivés souhaités, même si le milieu réactionnel reste riche en polyglycérol libre. Les produits les plus prometteurs de l’étude sont des copolyéthers de PDO et d’isosorbide, d’environ 600 g/mol, obtenus par éthérification en catalyse acide. Ces nouveaux copolyéthers ont des bouts de chaînes constitués d’unités isosorbide, sont hydrosolubles et ont une stabilité thermique améliorée par rapport aux PTEG. / The aim of this project is to prepare some new hydrophilic biobased copolyethers for cosmetic applications, similar to those of polyethylene glycol (PEG). Synthesis of polytrimethylene ether glycol (PTEG) which has a chemical structure close to the PEG was studied by polymerizing 1,3-propanediol (PDO) with sulfuric acid as catalyst. This acid catalyst is appropriate to promote the polymerization of PDO without excessive degradation. We tried to increase the solubility of PTEG in water by combining to PDO units hydrophilic monomers, such as isosorbide and glycerol, to the PDO units. We showed that etherification of isosorbide and PDO (or PTEG), in the presence of acid catalyst, gives new copolyethers structures, deeply characterized by NMR and mass spectroscopy. These copolyethers are preferably ended by isosorbide units due to different reactivity between isosorbide and PDO. The etherification of the PDO and glycerol with sulfuric acid results in a cross-linked and degraded product. Basic catalytic route favored the polymerization of glycerol on itself rather than the etherification on PDO units. We also grafted glycerol carbonate on PTEG oligomer but obtained a complex composition mixture rich in polyglycerol. The most promising products of the study are PDO and isosorbide copolyethers with a molar mass of 600 g/mol, obtained by etherification with sulfuric acid as catalyst. These copolyethers have chain ends constituted by isosorbide units, are water soluble and have a higher thermal stability compared to PTEG.
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Epoxy Adhesives: Formulation for Sustainability and Mechanism of AdhesionPatel, Ammar Abbas 28 January 2020 (has links)
No description available.
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Biopolymers processed and used as enzyme carriers / Processade biopolymerer som enzymbärareMészáros, Dániel January 2023 (has links)
Syftet med detta masterprojekt var att undersöka möjligheten att använda biobaserat, mjukgjort natriumalginat (NaAlg) som enzymbärare. Alginaterna görs traditionellt bearbetbara genom att tillsätta olika mjukgörare, såsom polyoler (glycerol, sorbitol, etc.), i detta arbete användes glycerol. Den experimentella aspekten av projektet involverade beredning i laboratorieskala av prover, som omfattade blandning, varmpressning, potentiell behandling med nedsänkning i kalciumbad och efterföljande torkning. Förlusten av kemikalier under bearbetningen kvantifierades med hjälp av termogravimetrisk analys (TGA) och ultraviolett-synlig spektroskopi (UV-Vis). De preparerade bearbetade proverna karakteriserades genom extraktionsexperiment. Under den första halvan av projektet undersöktes färgämnesladdningen av proverna för enkelhets skull. Senare byttes den laddade föreningen ut mot enzymer. UV-Vis-mätningar användes i båda fallen för att effektivt karakterisera proverna. De initialt preparerade mjukgjorda natriumalginatproverna var för känsliga och löstes lätt i vatten. Följaktligen utfördes experiment för att förbättra stabiliteten hos matrisen till en tillräcklig nivå genom jonbyte av natriumjoner till kalciumjoner. Denna process förbättrade avsevärt vattenstabiliteten hos proverna. Av resultaten verkar det som om frisättningen av den laddade föreningen kan kontrolleras genom jonbytesbehandlingen. När väl förbättrad vattenstabilitet hos matrisen upptäcktes, undersöktes effekten av mjukningsmedlet genom att ändra blandningsförhållandet för glycerol. Det visade sig att nivån av glycerol i provet är omvänt proportionell mot den laddade föreningens återhållbarhet. De enzymladdade proverna implementerades först med användning av lipasenzymer på grund av att de var lättillgängliga i laboratoriet. Inom kort visade det sig att analysen för att kvantifiera lipasaktivitet utförs i 2-metyl-2-butanol (2M2B), vilket inte orsakade någon svullnad i proverna som observerats tidigare. Därför byttes det laddade enzymet till Horseradish Peroxidase (HRP). Det visade sig att HRP-laddade prover hade aktivitet efter bearbetning. De vattenstabiliserade HRP-laddade proverna hade mätbar aktivitet under fyra timmars exponering för analysen. Förutom enzymatisk analys övervakades frisättningsprofilen för protein också med användning av Bradford-analysen. Man såg att efter en initial måttlig frisättning av enzymerna, planade frisättningen ut och upphörde efter fyra timmar. Resultaten av Bradford-analysen överensstämde med de enzymatiska aktivitetsmätningarna. Det bör noteras att den ursprungliga formuleringen av projektet var starkt baserad på en nyligen utvecklad bearbetningsmetod, extrudering för alginatkompositer. Tyvärr gjordes inga tester med extrudering på grund av tekniska svårigheter med instrumentet. / The aim of this master project was to investigate the possibility to use bio-based, plasticized sodium alginate (NaAlg) as enzyme carrier. The alginates are traditionally made processable by adding various plasticizers, such as polyols (glycerol, sorbitol, etc.), in this work glycerol was used. The experimental aspect of the project involved the lab-scale preparation of samples, which encompassed compounding, hot pressing, potential treatment with a calcium bath immersion, and subsequent drying. The loss of chemicals during processing was quantified using Thermogravimetric analysis (TGA) and Ultraviolet-Visible spectroscopy (UV-Vis). The prepared processed samples were characterized by extraction experiments. In the first half of the project, the colorant loading of the samples was investigated for simplicity. Later the loaded compound was exchanged for enzymes. UV-Vis measurements were employed in both cases to characterize the samples effectively. The initially prepared plasticized sodium alginate samples were too sensitive and readily dissolved in water. Consequently, experiments were performed to improve the stability of the matrix to a sufficient level by ion exchange of sodium ions to calcium ions. This process significantly improved the water stability of the samples. From the results, it seems the release of the loaded compound can be controlled by the ion exchange treatment. Once enhanced water stability of the matrix was found, the effect of the plasticizer was investigated by changing the mixing ratio of glycerol. It was found that the level of glycerol in the sample is inversely proportional to the restrainability of the loaded compound. The enzyme loaded samples first were implemented by the use of lipase enzymes due to being readily available in the laboratory. Shortly, it was found that the assay to quantify lipase activity is performed in 2-methyl-2-butanol (2M2B), which did not cause any swelling in the samples as observed before. Therefore, the loaded enzyme was switched to Horseradish Peroxidase (HRP). It was found that HRP loaded samples possessed activity after processing. The water stabilized HRP loaded samples possessed measurable activity over four hours of exposure to the assay. In addition to enzymatic assay, the release profile of protein was also monitored using Bradford assay. It was seen that after an initial moderate release of the enzymes, the release leveled off and stopped after four hours. The results of the Bradford assay aligned with the enzymatic activity measurements. It should be noted, that the original formulation of the project was heavily based on arecently developed processing method, extrusion for alginate composites. Unfortunately,no tests were performed with extrusion due to technical difficulties with the instrument.
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