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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Ekologiska byggmaterial – ett alternativ? : En analys av några ekologiska byggmaterial / Ecological building materials – an alternative? : An analysis of some ecological building materials

Furenberg, Andreas, Jörneman, Olof, Holm, Petter January 2007 (has links)
<p>Miljöförstöringen håller på att få allt för stora proportioner, vilket genom bland annat växthuseffekten leder till att vår planet snart är obeboelig för människan.</p><p>Byggbranschens andel i miljöförstöringen är onödigt stor genom transporter, energianvändning, maskinanvändning och miljömässigt dåliga material.</p><p>Vår frågeställning är: går det att ersätta de konventionella byggmaterialen med ekologiska sådana? JM vill även få beprövat om de är så bra, miljömässigt, som de tror. Detta ska besvaras genom en analys av tre ekologiska material som sedan jämförs med konventionella material för samma funktion.</p><p>Newbeam är ett material som planeras gå i produktion till hösten 2007. Det består av autoklaverad aspflis och ligninbaserat lim som pressas till profilerade balkar i önskad form. Denna produkt har i media benämnts ”stålbalk av trä” på grund av sin höga hållfasthet. Dess egenskaper liknar i många avseenden snarare stålbalkar än de traditionella träbalkarna. Priset på denna produkt beräknas bli cirka 20% lägre än motsvarande priskonkurrenter. Den är ämnad att användas som lastbärande strukturer för golvbjälklag, inner- och ytterväggar och takstolar.</p><p>BioBased är ett sojabaserat isoleringsmaterial som liknar fogskum. Det tillverkas i USA och finns ej tillgängligt i Sverige ännu. Det sprutas på plats och är helt lufttätt. Därmed monteras BioBased i ett steg och man slipper montera ångspärr samt vindskydd. Isoleringsförmågan är likvärdig med Isovers glasullsisolering.</p><p>Foamglas är ett beprövat isolermaterial med hög tryckhållfasthet och vid användande av Koljerntekniken kan det nyttjas som platta på mark. Dock kan det bara användas för laster upp till motsvarande ett femvånings trähus.</p><p>I jämförelsen betygsattes materialen enligt den mall vi gjort upp.</p><p>Vi fann att Newbeam är ett mycket bra alternativ till trä och stål, såväl ekologiskt som ekonomiskt. Vissa begränsningar finns dock. Det kan ej ersätta stål som material i långa pelare och balkar.</p><p>BioBased är även det ett godtagbart alternativ, men det produceras i USA. Det är detta faktum som gör att Isover vinner betygsjämförelsen.</p><p>Foamglaset vann jämförelsen mot betong. Dess fördelar gentemot betong är dels att man slipper torktider, Foamglasets lätta vikt och att det är återvinnings- och återbrukbart. Foamglasplattan är, i vår jämförelse, mer än dubbelt så dyr som en konventionell betongplatta.</p><p>JM, som valt att tackla miljöproblemen genom att bygga energisnåla hus, ligger bra till i sitt miljöarbete. Dock kan de göra mer genom att till exempel använda mer ekologiska byggmaterial.</p><p>Vi har, i rapporten, kommit fram till att det går att ersätta vissa material med ekologiskt sett bättre sådana.</p> / <p>The pollution of our planet is getting to big proportions, global warming leads to devastating effects on the planet. The building and construction industries part in the pollution is unnecessary big through transports, energy usage, machines and environmentally bad building materials.</p><p>The question at issue for the report is: Is it possible to replace the traditionally used materials today with new ecological ones?</p><p>JM gave us the commission to investigate if they are as good in environmental aspects as they believe. This will be answered through an analysis of three ecological materials which later will be compared to traditional materials with corresponding functions.</p><p>Newbeam is a material planned to go in production in fall 2007. This is a material based on aspen wood chips, bound together under high steamed pressure with lignin based glue to profiled beams in a requested shape.</p><p>This product has been named in media as “steel beam of wood” because of its similar superior strength. Its qualities resemble more to a steel beam than the traditional wood beams. The price of this product estimates to be around 20 % lower than corresponding competitors. Newbeam intends to be used as weight carrying structures for floor slabs, inner and outer walls and even for rafters.</p><p>BioBased is a soya-based insulation material similar to seam foam insulation. It is manufactured in the USA and not yet available in Sweden. It is sprayed to its location and completely airtight. With that, BioBased is assembled in only one step and no steam- or wind barrier is necessary. The insulation performance is similar to Isovers glass wool insulation.</p><p>Foamglas is a well tried insulation material with high pressure strength abilities and with usage of the Koljern technique it might be used as a ground plate. Even though it can only be used up to five floor wooden houses.</p><p>We valued the materials in a comparison between them according to the template we constructed. We found out that Newbeam is a good alternative to wood and steel, both ecological and economical. There are some limitations though, it can not replace steel as a material in long columns and beams.</p><p>Even BioBased is a good alternative but it is manufactured in the USA. It is this fact that lets Isover coming up ahead in the comparison.</p><p>Foamglas won its comparison against concrete. Its advantages against concrete are that you avoid dry time, it is light weighted and that it is recyclable and reusable. The Foamglas ground plate is, in our comparison, more than twice as expensive as a conventional concrete ground plate. JM, that has chosen to handle the environmental issues with building low energy usage houses, have reached a good level in their work for the environment. Even though, they can do a lot more through e.g. use more ecological building materials.</p><p>We have, in the report, made the conclusion that it is possible to replace some materials with ecological better ones.</p>
22

Ekologiska byggmaterial – ett alternativ? : En analys av några ekologiska byggmaterial / Ecological building materials – an alternative? : An analysis of some ecological building materials

Furenberg, Andreas, Jörneman, Olof, Holm, Petter January 2007 (has links)
Miljöförstöringen håller på att få allt för stora proportioner, vilket genom bland annat växthuseffekten leder till att vår planet snart är obeboelig för människan. Byggbranschens andel i miljöförstöringen är onödigt stor genom transporter, energianvändning, maskinanvändning och miljömässigt dåliga material. Vår frågeställning är: går det att ersätta de konventionella byggmaterialen med ekologiska sådana? JM vill även få beprövat om de är så bra, miljömässigt, som de tror. Detta ska besvaras genom en analys av tre ekologiska material som sedan jämförs med konventionella material för samma funktion. Newbeam är ett material som planeras gå i produktion till hösten 2007. Det består av autoklaverad aspflis och ligninbaserat lim som pressas till profilerade balkar i önskad form. Denna produkt har i media benämnts ”stålbalk av trä” på grund av sin höga hållfasthet. Dess egenskaper liknar i många avseenden snarare stålbalkar än de traditionella träbalkarna. Priset på denna produkt beräknas bli cirka 20% lägre än motsvarande priskonkurrenter. Den är ämnad att användas som lastbärande strukturer för golvbjälklag, inner- och ytterväggar och takstolar. BioBased är ett sojabaserat isoleringsmaterial som liknar fogskum. Det tillverkas i USA och finns ej tillgängligt i Sverige ännu. Det sprutas på plats och är helt lufttätt. Därmed monteras BioBased i ett steg och man slipper montera ångspärr samt vindskydd. Isoleringsförmågan är likvärdig med Isovers glasullsisolering. Foamglas är ett beprövat isolermaterial med hög tryckhållfasthet och vid användande av Koljerntekniken kan det nyttjas som platta på mark. Dock kan det bara användas för laster upp till motsvarande ett femvånings trähus. I jämförelsen betygsattes materialen enligt den mall vi gjort upp. Vi fann att Newbeam är ett mycket bra alternativ till trä och stål, såväl ekologiskt som ekonomiskt. Vissa begränsningar finns dock. Det kan ej ersätta stål som material i långa pelare och balkar. BioBased är även det ett godtagbart alternativ, men det produceras i USA. Det är detta faktum som gör att Isover vinner betygsjämförelsen. Foamglaset vann jämförelsen mot betong. Dess fördelar gentemot betong är dels att man slipper torktider, Foamglasets lätta vikt och att det är återvinnings- och återbrukbart. Foamglasplattan är, i vår jämförelse, mer än dubbelt så dyr som en konventionell betongplatta. JM, som valt att tackla miljöproblemen genom att bygga energisnåla hus, ligger bra till i sitt miljöarbete. Dock kan de göra mer genom att till exempel använda mer ekologiska byggmaterial. Vi har, i rapporten, kommit fram till att det går att ersätta vissa material med ekologiskt sett bättre sådana. / The pollution of our planet is getting to big proportions, global warming leads to devastating effects on the planet. The building and construction industries part in the pollution is unnecessary big through transports, energy usage, machines and environmentally bad building materials. The question at issue for the report is: Is it possible to replace the traditionally used materials today with new ecological ones? JM gave us the commission to investigate if they are as good in environmental aspects as they believe. This will be answered through an analysis of three ecological materials which later will be compared to traditional materials with corresponding functions. Newbeam is a material planned to go in production in fall 2007. This is a material based on aspen wood chips, bound together under high steamed pressure with lignin based glue to profiled beams in a requested shape. This product has been named in media as “steel beam of wood” because of its similar superior strength. Its qualities resemble more to a steel beam than the traditional wood beams. The price of this product estimates to be around 20 % lower than corresponding competitors. Newbeam intends to be used as weight carrying structures for floor slabs, inner and outer walls and even for rafters. BioBased is a soya-based insulation material similar to seam foam insulation. It is manufactured in the USA and not yet available in Sweden. It is sprayed to its location and completely airtight. With that, BioBased is assembled in only one step and no steam- or wind barrier is necessary. The insulation performance is similar to Isovers glass wool insulation. Foamglas is a well tried insulation material with high pressure strength abilities and with usage of the Koljern technique it might be used as a ground plate. Even though it can only be used up to five floor wooden houses. We valued the materials in a comparison between them according to the template we constructed. We found out that Newbeam is a good alternative to wood and steel, both ecological and economical. There are some limitations though, it can not replace steel as a material in long columns and beams. Even BioBased is a good alternative but it is manufactured in the USA. It is this fact that lets Isover coming up ahead in the comparison. Foamglas won its comparison against concrete. Its advantages against concrete are that you avoid dry time, it is light weighted and that it is recyclable and reusable. The Foamglas ground plate is, in our comparison, more than twice as expensive as a conventional concrete ground plate. JM, that has chosen to handle the environmental issues with building low energy usage houses, have reached a good level in their work for the environment. Even though, they can do a lot more through e.g. use more ecological building materials. We have, in the report, made the conclusion that it is possible to replace some materials with ecological better ones.
23

Life Cycle Assessment of a Hybrid Poly Butylene Succinate Composite

Moussa, Hassan 24 January 2015 (has links)
Poly butylene succinate (PBS) is a biodegradable plastic polymer that has physical and mechanical properties similar to common petroleum plastics like polypropylene (PP) and polyethylene (PE). PBS may be produced from petroleum or bio-based feedstocks, or by a hybrid combination of petroleum and bio-based resources. Producers are reducing content of petroleum components used for the production of PBS, and by doing so are seeking potential environmental performance improvements. In this study, ???hybrid??? PBS refers to the production of PBS polymer from bio-based succinic acid (SAC) sourced from sorghum and petroleum-based 1, 4-butanediol (BDO). Given its biodegradability, PBS is commercially used for compostable bags and agricultural mulching film applications. A recent study in Ontario identified composite materials made with PBS blended with natural fibres like switchgrass (SG) as promising for applications in automotive products. Such novel composite materials are touted as potential bio-based alternatives to conventional petroleum-based plastics. Of the few studies that have considered the environmental performance of PBS materials, none have assessed the potential environmental impacts of a hybrid PBS composite. Therefore, this study undertook a life cycle assessment (LCA) of SG reinforced hybrid PBS composite (hybrid composite). LCA is an environmental management technique that is used to assess environmental aspects (inputs and outputs) and potential environmental impacts of a product or service throughout its life cycle. The analysis considered a cradle-to-gate system boundary and evaluated eleven environmental performance indicators. The environmental performance of the hybrid composite was compared to a conventional glass fibre (GF) reinforced polypropylene (PP) composite (baseline composite), a material that is widely used in automotive components. Results showed that the production of the hybrid composite in comparison to the baseline composite decreased potential impact for most of the assessed indicators: cumulative energy demand by 40%, waste heat by 23%, global warming potential by 35%, smog by 2%, carcinogens by 54%, non-carcinogens by 172%, respiratory effects by 22% and ecotoxicity by 45%. Increases in the values of impact indicators were apparent for ozone depletion, acidification, and eutrophication by 43%, 16%, and 322%, respectively. Analysis revealed that dominant influences on results were not related directly to the bio-based make-up. Rather, the biggest influence on the environmental performance of composite production were the sources of heat used in petroleum-based materials, the energy mix in electricity for bio-based materials, the type of reinforcing fibre and the co-product treatment methodology used. The study helps fill a gap in knowledge regarding bio-based chemicals and hybrid biodegradable plastic composites, and points to opportunities for future research on feedstocks for industrial composite materials. The importance of this study is that it helps to identify the environmental strengths and weaknesses associated with the production of the hybrid composite specifically, and bio-based materials more generally. It points to alternative material substitution options for use in the automotive industry. In this study, life cycle assessment exemplifies multidisciplinary methodologies, which seek to traverse the boundaries between the social and natural sciences and disciplines to support more sustainable policy decisions for a bio-economy. The systematic nature and the widely applicable consequences of this LCA study have the potential to contribute to industrial and business management, and reach the public policy arena in an effort to drive environmental and social change.
24

Improvement of compatibility of poly(lactic acid) blended with natural rubber by modified natural rubber

Chumeka, Wannapa 11 December 2013 (has links) (PDF)
The aim of this research work was to improve the compatibility of polymer blends made from poly(lactic acid) and natural rubber (PLA/NR blends) by using modified natural rubber as a compatibilizer. Natural rubber was chemically modified into two categories: natural rubber grafted poly(vinyl acetate) copolymer (NR-g-PVAc) and block copolymers (PLA-NR diblock copolymer and PLA-NR-PLA triblock copolymer). PLA/NR blends were prepared by melting blending in a twin screw extruder and compression molded to obtain a 2-mm thick sheet. The blends contained 10-20 wt% of NR and modified NR, and the impact strength and tensile properties were investigated. The compatibilization effect was determined by DMTA, DSC and SEM. NR-g-PVAc was synthesized by emulsion polymerization to obtain different PVAc graft contents (1%, 5% and 12%). Characterization by DMTA showed an enhancement in miscibility of the PLA/NR-g-PVAc blends. NR-g-PVAc could be used as a toughening agent of PLA and as a compatibilizer of the PLA/NR blend. The block copolymers were synthesized following two routes: (1) hydroxyl telechelic natural rubber (HTNR) and lactide and (2) HTNR and PLA prepolymer. In the former route, lactide was in situ polymerized via a ring opening polymerization to be a PLA block segment during block copolymerization. In the latter route PLA prepolymer was synthesized by a condensation polymerization of L-lactic acid prior to block copolymerization. Both block copolymers acted as good compatibilizers for the PLA/NR blend by increasing the impact strength and decreasing the NR particle size. Triblock copolymers provided higher impact strength than diblock copolymers, and they were a less effective compatibilizer than NR-g-PVAc. In contrast to NR and NR-g-PVAc, the block copolymer was not a good toughening agent for PLA.
25

Reactive molding and self-assembly techniques for controlling the interface and dispersion of the particulate phase in nanocomposites.

Pranger, Lawrence A. 07 November 2008 (has links)
This research explored the processing and properties of PNCs using a polyfurfural alcohol (PFA) matrix. The precursor for PFA, furfuryl alcohol (FA) is sourced from feedstocks rich in hemicellulose, such as corn cobs, oat hulls and wood. To exploit FA as a polymerizable solvent, cellulose whiskers (CW) and montmorillonite clay (MMT) were used as the nanoparticle phase. Results from PNC processing show that CW and MMT can be dispersed in the PFA matrix by means of insitu polymerization, without the use of surfactants or dilution in solvents. Both CW and MMT nanoparticles catalyze the polymerization of furfuryl alcohol (FA). Moreover, the insitu intercalative polymerization of FA in the interlayer galleries of MMT leads to the complete exfoliation of the MMT in the PFA matrix. CW and MMT both function as effective matrix modifiers, increasing the thermal stability of PFA nanocomposites compared to pure PFA polymer. The increased thermal stability is seen as significant increases in the onset of degradation and in residual weight at high temperature. This research also explored the surface functionalization of Cu, Ni and Pt substrates by self-assembly of a range of difunctional linker molecules. Characterization by XPS and PM-IRRAS indicate that diisocyanides and dicarboxylic acids both form chemically "sticky" surfaces after self-assembly on Cu and Ni. Sticky surfaces may provide a means of increasing nanoparticle dispersion in metal nanocluster filled PNCs, by increasing their interaction with the matrix polymer. Another potential application for sticky surfaces on Cu is in the ongoing miniaturization of circuit boards. The functionalization of Cu bond pad substrates with linker molecules may provide an alternate means of bonding components to their bond pads, with higher placement accuracy compared to solder bumps.
26

Structure et propriétés physiques de composites à matrice biosourcée/fibres naturelles continues pour applications aéronautiques / Structure and physical properties of bio-based matrix/continuous natural fibers composites for aeronautic applications

Haddou, Geoffrey 11 December 2017 (has links)
L'objectif de ce travail est de proposer des composites totalement biosourcés à application potentielle pour l'aménagement cabine et conforme aux exigences REACh. L'utilisation de fibres végétales comme renforts de matrices polymères est une voie prometteuse qui permet de réduire l'impact environnemental, tout en diminuant la masse. Une nouvelle matrice polyamide biosourcée synthétisée par Arkema - Polyamide méta-xylylène diamine 10 - a été utilisée pour cette étude. Une étude préliminaire de composites Polyamide 11/poudre de bambou a montré que l'introduction du renfort ne perturbait pas la structure physique de la matrice. De plus, l'optimisation des propriétés mécaniques s'effectue en l'absence d'agent de couplage. Les composites fibres continues de bambou/PA mXD 10 qui sont également mis en œuvre sans agent de couplage, ont des modules de cisaillement supérieurs à ceux des composites synthétiques de référence fibre de verre/matrice phénolique, avec un gain de masse de l'ordre de 50%. / The aim of this work is to propose fully bio-based composites for a potential application in the cabin interior, and compliant with the REACh regulations. The use of vegetable fibers as reinforcement into polymeric matrices is an encouraging way to decrease the environmental impact, end the weight as well. A new bio-based polyamide matrix, synthetized by Arkema - Polyamide meta-xylylene diamine 10 - was used in this work. A preliminary study on Polyamide 11/bamboo powder showed the introduction of the fillers did not modified the physical structure of the matrix. Moreover, the optimization of the mechanical properties occurs with no coupling agent. The continuous bamboo fibers/PA mXD 10 composites, which were also processed without coupling agent, present shear moduli superior than the one of the synthetic reference glass fibers/phenolic, with a gain of weight about 50%.
27

Conception, mise en oeuvre et caractérisation de nouveaux bio-nano-matériaux fonctionnels. / Design, processing and characterisation of innovative functional bio-nano-materials for packaging

Lavoine, Nathalie 15 November 2013 (has links)
De nouveaux matériaux, appelés matériaux actifs, se développent actuellement par diverses processus dans plusieurs applications. L'objectif est d'apporter aux matériaux de bases (par exemple : papiers, cartons) de nouvelles fonctionnalités telles que la détection de virus, le relargage de substances actives, le contrôle de la durée de vie etc. L'élaboration de matériaux fonctionnels est un sujet de plus en plus important dans notre société et chez les industries. Les recherches restent cependant encore rares à ce propos et l'expertise des scientifiques est vivement attendue. Par ailleurs, l'intérêt des scientifiques se porte aussi de plus en plus sur l'utilisation de bio-matériaux. Parmi ces derniers, l'intérêt pour les bio nanoparticules est le plus grandissant : les chercheurs voient en effet la possibilité d'élaborer de nouvelles applications à hautes valeurs ajoutées. Cependant, aujourd'hui, l'utilisation de ces nanoparticules dans le contrôle du relargage de substances actives n'est pas encore dominante ni approfondie malgré les premiers résultats prometteurs obtenus avec les nanoparticules. En plus de leurs excellentes propriétés mécaniques et barrières, leur surface spécifique est un point clé et avantageux à considérer pour l'obtention de nouvelles fonctionnalités (introduction de substances actives). Dans le domaine des emballages, les matériaux actifs ont pour objectif de prolonger la durée de conservation des aliments en modifiant les conditions d'emballage. Trois catégories sont différenciées : les emballages absorbeurs (oxygène, humidité), les emballages antimicrobiens et les emballages barrières. Peu de recherches existent actuellement sur les deux premières catégories et d'autres commencent affichant des résultats bien prometteurs. Ainsi, l'objectif de la thèse est donc de comprendre et de développer des bio nanomatériaux fonctionnels innovants en considérant deux aspects : le développement durable et la sécurité alimentaire. Trois sujets seront abordés en détail: - Biomatériaux : fibres de cellulose, bionanoparticules, biomolécules actives - Procédés : greffage, encapsulation, couchage, extrusion, jet d'encre - Propriétés : absorbeur d'oxygène, antimicrobien, contact alimentaire Le phénomène de migration sera un point particulièrement détaillé au long de ces 3 ans ainsi que les caractérisations de propriétés importantes pour le produit final. Différentes stratégies seront ensuite testées et la meilleure solution sera optimisée afin d'arriver à une étude à grand échelle du produit obtenu. / New functional materials, called active materials, are developing with different processes and for several applications. The target is to give new functions like virus detection, active substance release, end of life control...This topic is more and more important in our society and industry. Researches are still rare and more scientific expertise is expected. Meanwhile, use of biobased materials interests more and more scientists. Among biomaterials, the use of bionanoparticles is strongly increasing and high value added applications are targeted. However, their use in release control of active substances has not yet been studied in detail in spite of promising results on barrier properties improvement. Their very high specific area could also be considered as a advantege concerning their use as active material carrier. In packaging field, active materials are materials which change condition of packed product to increase its shelf life by keeping quality and safety. Three main types of active packaging are existing : scavenger systems (02, humidity), anti-microbial systems, barrier systems. Some research studies have just been launched about the two first categories of active packaging with some promising results. The target is then to understand and develop innovative functional bionanomaterials by considering : sustainability and safety. Three topic will be studied in detail : - Biomaterials : cellulose fibers, bionanoparticules (NFC, Wh, SNP), active biomolecules - Process : grafting, encapsulation chitosane, coating, extrusion, ink jet - Properties : 02 scavenger, anti-microbial system, food contact A better understanding of migration and the end-use properties characterization will be main point of the scientific research during the project. Different strategies will be tested and optimisation of best solution will follow by finishing with an up-scaling study.
28

Elaboration de polymères biosourcés pour application dans un matériau composite à base de farine de liège / Development of bio-based polymers for use in cork composites

Darroman, Emilie 12 December 2014 (has links)
Les travaux présentés concernent le développement d'un matériau composite (farine de liège, liant et additif) pour l'élaboration de bouchons technologiques mis en œuvre par un procédé de moulage. Dans le cadre de ces travaux, la synthèse, la caractérisation et la formulation d'un polymère biosourcé ont été développées en tant que liant de ce matériau composite. La stratégie de cette thèse a été de développer un polymère obtenu par polycondensation d'un composé époxydique avec un agent réticulant de type amine. Dans un premier temps, une caractérisation approfondie du liant utilisé par DIAM Bouchage a été réalisée pour définir le cahier des charges du nouveau polymère. L'étude de composés époxydiques et amines ont permis de sélectionner des précurseurs commerciaux biosourcés et non-classés CMR qui répondent au cahier des charges. De nouveaux précurseurs époxydiques et amines ont été synthétisés à partir de bioressources telles que la vanilline et les dérivés d'acide gras. La synthèse de résines époxy-amines a été effectuée grâce aux précurseurs commerciaux sélectionnés et ces résines ont été caractérisées thermiquement, mécaniquement et physiquement. Finalement, des bouchons technologiques ont été synthétisés selon différentes formulations et caractérisés pour évaluer leur adéquation avec les spécifications de DIAM Bouchage. / The presented study concerns the development of a composite material (cork flour, binder and additive) in order to produce of technological cork-stoppers carried out by a molding process. As part of this work, the synthesis, the characterization and the formulation of a biobased polymer have been developed as a binder of the composite material. The strategy of this thesis was to develop a polymer obtained by polycondensation of an epoxy compound with an amine curing agent.As a first step, a thorough characterization of the binder used by DIAM Bouchage was carried out to define the specifications of the novel polymer. The study of epoxy and amine compounds led to the selection of biobased commercial and non-classified CMR precursors that meet the specifications. Novel epoxy and amine precursors were synthesized from biobased resources such as vanillin and fatty acid derivatives. The synthesis of epoxy-amine resins was performed with the selected commercial precursors and these resins were characterized thermally, mechanically and physically. Finally, different formulations of technological cork-stoppers were synthesized and characterized to evaluate their suitability with the DIAM Bouchage specifications.
29

Development of novel building insulation materials, incorporating cellulose and biobased additives / Nouveaux isolants pour le batiment, à base de ouate de cellulose et additifs biosourcés

Lopez Hurtado, Pablo 08 September 2016 (has links)
La ouate de cellulose utilisée pour l’isolation est fabriquée à partir de fibres de papier broyé, traitées avec des additifs minéraux agissant comme agents ignifuges et antifongiques. La conductivité thermique du matériau final est aux alentours de 0,04 W/m.K, ce qui est comparable à la laine de verre, avec l’intérêt d’être fabriqué à partir de matériaux recyclés, représentant un taux d’énergie grise beaucoup plus faible. Le mode de mise en oeuvre par voie humide de la ouate de cellulose a plusieurs avantages par rapport à la voie sèche. Le fait que les fibres de cellulose se rigidifient avec l’eau, empêche le tassement du matériau, qui peut engendrer des ponts thermiques dans l’enveloppe du bâtiment. Par contre, la durée de séchage peut être très longue et variable selon le dosage utilisé et les conditions ambiantes d’application. Ce projet de recherche vise à trouver l’additif idéal permettant d’accélérer le séchage tout en conservant une bonne cohésion du matériau et le maintien de ses propriétés isolantes. Deux types de ouate de cellulose utilisés en isolation ont été caractérisés. Ils ont montré des différences de composition chimique, granulométrie et morphologie. L’influence de leurs caractéristiques physiques telles que la rétention d’eau, les isothermes d’adsorption d’eau et les proportions d’eau libre et liée sur le séchage du matériau final a été mise en évidence. Du point de vue de la mise en oeuvre, il a été démontré que le dosage en eau avait un impact important sur les propriétés finales du matériau. La densité, la résistance en compression et la conductivité thermique augmentent avec le dosage en eau. Un minimum de 14 kPa pour le module de compression a été défini comme le seuil de résistance permettant d’éviter le tassement. Ces propriétés ont été comparées avec celles de la ouate de cellulose compactée à sec et les résultats ont montré la forte influence de la rigidification et de la fermeture des pores du matériau. Deux voies ont été envisagées pour résoudre le problème du temps de séchage : l’ajout d’additifs aux propriétés adhésives permettant de réduire la quantité d’eau introduite en renforçant la cohésion de l’isolant, et l’ajout d’additifs permettant de modifier la tension de surface pour faciliter le départ de l’eau. Les additifs biosourcés potentiels ont été caractérisés à différentes concentrations et classés selon leur viscosité et leur pouvoir collant. Malheureusement plusieurs additifs ont dû être rejeté car ils présentaient un couple « propriété adhésive/pompabilité » non adapté. Une gamme de tensioactifs a également été testée par rapport à leurs tensions de surface. Les formulations pompables ont étés caractérisées par rapport à leurs temps de séchage, résistance en compression et conductivité thermique. Les additifs qui ont montré des contributions positives sur le séchage sont les lignosulfonates et le tensioactif cationique CTAB. L’influence de ces deux additifs a ensuite été étudiée avec un modèle numérique à travers le logiciel WUFI en prenant en compte l’impact sur le séchage, la météo, le dosage liquide et l’épaisseur de l’isolant. Les conditions optimales ont été définies. Le lignosulfonate s’est avéré être l’additif le plus efficace. Une première évaluation de la performance des nouveaux isolants en termes de résistance au feu et à la moisissure a été réalisée et des indications pour la suite de l’étude ont été proposées. / Cellulose insulation is manufactured from recycled paper fibres, treated with mineral additives acting as flame retardants and antifungals. Its consistency is similar to cotton wool. The fibres are sold in bulk to be blown into the walls and attics. Its thermal conductivity is around 0.04 W/m.K, which is comparable to glass wool, but it is made with recycled materials and has much lower embodied energy levels. It can be either blown dry or sprayed with water. The wet spray method for cellulose insulation has several benefits compared to the dry process. Since the cellulose fibres become rigid after drying, it prevents the compaction of the material thus avoiding thermal bridges in the building envelope. However, the time to reach the dry state may be very long and variable depending on the dosage used and the environmental conditions of application. There are many bio-based additives that can contribute to the reduction of this period and improve the cohesion of the material. This research project aims to find the optimal additive for this application while retaining the favourable properties of the insulating material. Two cellulose types have been characterized with regards to the properties of the fibres to determine their performance with water. Both samples showed differences in chemical composition, grain size, and morphology. The values of water retention, water adsorption isotherms and the proportions of free and bound water have been factors which have shown an influence on the drying of the insulation. Density, compressive strength, and thermal conductivity increased with moisture dosage. A minimum of 14 kPa for the compression module was defined as the resistance threshold to avoid settling. These properties were compared with those of the cellulose insulation compacted to dryness and the results showed the strong influence of the stiffening and pore closing process upon drying, on these properties. Potential bio-based additives were classified and characterized with regards between concentration, viscosity, and adhesive strength. A relationship between these parameters was established. Most showed Newtonian behaviour at low concentrations, with some non- Newtonian concentrations having a pumpable viscosity. Unfortunately several additives which showed good adhesive properties were too viscous and vice versa. A range of surfactants were also considered. Sprayable formulations were characterized with respect to their drying time, compressive strength and thermal conductivity. Additives which have shown positive contributions drying are the lignosulfonate and the cationic surfactant CTAB. The influence of these additives on drying, with varying weather, liquid dosage and thickness of insulation was defined with a numerical model through the WUFI software. Optimal conditions in which the lignosulfonate additive is more effective have been defined. A first assessment of the performance of new formulation in terms of fire and mould was made and indications for the continuation of the study of the material were formalized.
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Valorisation de la biomasse pour l'élaboration de matériaux bioactifs sous irradiation / Valorization of biomass for the design of bioactive materials under irradiation

Modjinou, Tina 03 July 2017 (has links)
La valorisation des dérivés phénoliques et terpéniques issus de la biomasse s’insère parfaitement dans le défi actuel de nos sociétés qui pousse la chimie traditionnelle à évoluer vers une chimie durable. De par leur nature insaturée, les terpènes se montrent particulièrement intéressants pour synthétiser de nouveaux matériaux par réaction de chimie thiol-ène. Parallèlement, les dérivés phénoliques peuvent être facilement modifiés en synthons insaturés, susceptibles de réagir dans ces mêmes réactions. Ainsi, une large gamme de matériaux à base de linalol et d’eugénol a été élaborée sous irradiation UV. Une approche par photochimie a été privilégiée puisqu’elle s’inscrit parfaitement dans le cadre d’une chimie plus respectueuse de l’environnement. L’effet bénéfique des fonctions oxygénées du linalol et du phénol de l’eugénol sur l’activité antibactérienne a été démontré contre deux souches bactériennes principalement responsables du développement des maladies nosocomiales : S. aureus et E. coli. L’incorporation de nanoparticules de ZnO, de carvacrol ou d’acide tannique lors de la réaction de réticulation permet d’améliorer les propriétés antimicrobiennes de manière significative. L’association avec des polyesters semi-cristallins biosourcés et biodégradables présente une alternative intéressante pour optimiser les performances thermomécaniques des matériaux obtenus.Un deuxième type de matériaux a été synthétisé par photo-réticulation de dérivés phénoliques époxydés comme le résorcinol ou l’eugénol. La polymérisation cationique par ouverture de cycle photoamorcée permet la synthèse de matériaux dont les propriétés mécaniques sont plus élevées que les matériaux obtenus par réaction thiol-ène, et d’autre part de s’affranchir de l’agent réticulant à base de thiol. La synthèse de différents dérivés de l’eugénol mono-époxydés offre l’avantage de pouvoir moduler la composition des matériaux obtenus qui peuvent contenir des fonctions phénol et/ou des insaturations. Les groupements phénols sont indispensables à l’activité antibactérienne et sont à l’origine des propriétés anti-oxydantes. La possibilité d’introduire des insaturations permet une post- fonctionnalisation de la surface des matériaux.Ainsi une large gamme de matériaux réticulés, biosourcés et bioactifs dont les propriétés varient de l’élastomère au thermodurcissable a été synthétisée sous irradiation / The valorization of phenolic and terpene derivatives of biomass is perfectly in line with the current challenge of our societies that drives traditional chemistry to evolve towards a sustainable chemistry. Because of their unsaturated nature, terpenes are particularly interesting for synthesizing new materials by thiol-ene chemistry. At the same time, the phenolic derivatives can easily be modified to unsaturated synthons capable of reacting in these same reactions. Thus, a wide range of materials based on linalool and eugenol has been developed under UV irradiation. An approach by photochemistry has been selected since it fits perfectly within the framework of a chemistry more respectful of the environment. The beneficial effect of the oxygenated functions of linalol and phenolic functions of eugenol on antibacterial activity was demonstrated against two bacterial strains mainly responsible for the development of nosocomial diseases: S. aureus and E. coli. The incorporation of ZnO nanoparticles, carvacrol or tannic acid during the crosslinking reaction makes it possible to improve the antimicrobial properties significantly. The association with semi-crystalline biobased and biodegradable polyesters presents an interesting alternative to optimize the thermomechanical performance of the obtained materials.A second type of materials has been synthesized by photocrosslinking epoxidized phenolic derivatives such as resorcinol or eugenol. The photoinitiated cationic polymerization by opening of the ring enables the synthesis of materials whose mechanical properties are higher than the materials obtained by thiol-ene reaction and on the other hand to get rid of the thiol-based crosslinking agent. The synthesis of various monoepoxidized eugenol derivatives offers the advantage of being able to modulate the composition of the obtained materials which may contain phenol functions and / or unsaturations. The phenol groups are essential to the antibacterial activity and lead to the antioxidant properties. The possibility of introducing unsaturations allows a post-functionalization of the surface of the materials.Thus, a wide range of crosslinked, biosourced and bioactive materials whose properties vary from elastomer to thermosetting have been synthesized under irradiation

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