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Estudo morfológico do PVDF e de blendas PVDF/P(VDF-TrFE). / Morphological study of PVDF and PVDF/P(VDF-TrFE) blends.Rosa Cristina Capitão 08 March 2002 (has links)
O poli(fluoreto de vinilideno) (PVDF) é um polímero semicristalino que quando cristalizado a partir da fusão à temperaturas acima de 155°C apresenta uma variada morfologia cristalina, constituída por esferulitos anelados, não anelados e mistos. Abaixo dessa temperatura somente os esferulitos anelados são formados. Neste trabalho foi realizado um estudo morfológico do PVDF, procurando verificar a relação entre o tipo de esferulito formado e a fase cristalina predominante em suas lamelas. Foi verificado, por espectroscopia no infravermelho, que os esferulitos anelados apresentam exclusivamente a fase alfa, quando a cristalização ocorre a temperaturas inferiores a 155°C. Temperaturas superiores a essa induzem nessas estruturas uma transformação de fase alfa em gama, que aumenta a quantidade de fase gama com o tempo de cristalização. A taxa com que essa transformação ocorre aumenta com a temperatura de cristalização. Os esferulitos não anelados são constituídos predominantemente pela fase gama, cristalizada diretamente do fundido, com pequenas inclusões de fase alfa. O processo de fusão dos diferentes esferulitos, observado por microscopia ótica (MOLP) e medidas calorimétricas (DSC), mostraram que a temperatura de fusão da fase gama originada da transformação de fase é 8°C superior à daquela cristalizada diretamente do fundido. Micrografias de amostras aquecidas até 186°C e rapidamente resfriadas permitiram visualizar as regiões dos esferulitos anelados que sofreram a transformação de fase alfa em gama, para diferentes tempos e temperaturas de cristalização. Foi realizado, ainda, um estudo morfológico de blendas PVDF/P(VDF-TrFE), com diferentes composições e com o copolímero contendo 72% em mol de VDF. Análises térmicas (DSC) verificaram que os componentes da blenda são imiscíveis na fase cristalina, quando a cristalização ocorre a partir da fusão. Porém, micrografias obtidas por MOLP e MEV indicaram a presença de moléculas do copolímero nas regiões interlamelares dos esferulitos formados durante a cristalização do PVDF. Esse resultado sugere a miscibilidade entre os componentes no estado líquido, e que esta mistura íntima deve permanecer durante a cristalização, resultando na miscibilidade dos componentes na fase amorfa. / Poly(vinylidene fluoride) (PVDF) is a semi crystalline polymer that, when is crystallized from the melt at temperatures above 155°C, it presents a multiform morphology composed of ringed, non-ringed and mixed spherulites. Above this temperature only ringed spherulites are formed. In this work a morphological study of PVDF was performed, endeavoring to investigate the relation between the type of spherulite formed and the dominant crystalline phase in their lamellas. Infrared spectroscopy showed that the ringed spherulites are formed exclusively by the alpha phase when crystallization takes place at temperatures below 155°C. Higher temperatures induce a solid-state alpha in gamma phase transformation in these structures, increasing the amount of gamma phase with crystallization time. The rate at which this transformation takes place increases with crystallization temperature. The non-ringed spherulites consist predominantly of the gamma phase, crystallized from the melt, with small alpha phase inclusions. The melt process of the different spherulites, observed by optical microscopy (MOLP) and calorimetric measurements (DSC) showed that the melt temperature of the gamma phase originated from the phase transition is 8°C higher than that crystallized directly from the melt. Micrographs of samples heated up to 186°C and quickly cooled allowed visualization of the ringed spherulite regions, which underwent the alpha in gamma phase transformation at different crystallization times and temperatures. In addition, it was observed a morphological study of blends, with different compositions and the copolymer containing 72 mol% of VDF. Thermal analysis (DSC) showed that blend components are immiscible on crystalline phase, when the crystallization from the melt occurs. However, micrographs obtained from MOLP and MEV indicated the presence of copolymer on spherulites interlamellar regions, formed during PVDF crystallization. This result suggests miscibility between the components in the liquid state, and this intimate mixture must remain during crystallization, resulting in miscibility of the components in amorphous phase.
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Estudo da miscibilidade de blendas de poli(hidroxibutirato)/poli(álcool vinílico) obtidas por mistura mecânica / Miscibility studies on poly(hydroxybutyrate)/poly(vinyl alcohol) blends obtained mechanical mixingDeliane da Silva Cabral 21 February 2017 (has links)
Poli(hidroxibutirato) (PHB) é um polímero com um alto potencial de aplicação industrial, pois é biodegradável, tem propriedades físicas semelhantes ao poli(propileno) e é o mais abundante de sua classe, os poli(hidroxialconoatos). Porém, sua rigidez e fragilidade, combinadas com seu elevado custo de produção, têm limitado sua utilização em larga escala. Nesse sentido o PHB pode ser utilizado para o desenvolvimento de novos materiais como blendas, que são mais viáveis em comparação aos métodos de síntese. Estudos de blendas PHB/PVA por solução reportam boa compatibilidade entre os componentes, porém esse processo apresenta baixa produção, já que ampliação de escala é dificultada. Neste trabalho, blendas de PHB/PVA nas composições de 90:10, 75:25 e 50:50 em massa e plastificadas com glicerol foram obtidas por meio de mistura mecânica, utilizando uma extrusora rosca simples. As técnicas de espectroscopia no infravermelho por transformada de Fourier (FTIR), calorimetria exploratória diferencial (DSC), análise térmica dinâmico-mecânica (DMTA) e microscopia eletrônica de varredura (MEV) foram empregadas para estudar a miscibilidade das blendas. Os principais resultados indicam que as blendas são miscíveis: i) deslocamentos de bandas dos espectros de FTIR das blendas nas regiões de 1277 e 1054 cm-1 indicando interações intermoleculares fortes no sistema, como por exemplo polares e ligações de hidrogênio, ii) Tg única e intermediária às Tgs dos polímeros puros observada nas curvas do DMTA para as blendas, e iii) a ausência de duas fases nas imagens do MEV realizadas para as blendas com 90% de PHB após extração em meio aquoso da possível fase rica em PVA. Também foi possível observar que a cristalinidade do PHB não foi afetada significativamente pela adição de PVA como mostrado pelos resultados de DSC e difratometria de raios X (DRX). / Poly(hydroxybutyrate) (PHB) is a polymer with high potential for industrial applications, because it is biodegradable, has similar physical properties to poly (propylene) and is the most abundant in its class, the poly(hydroxyalconoates). However, its rigidity and fragility, combined with its high production cost, have limited its use in large-scale. Thus, PHB could be used to develop new materials as blends, which are more feasible compared to synthesis methods. Studies of PHB/PVA blends via solution shows good compatibility between the components, nevertheless, this process presents low production, since scaling up is hard to do. In this work blends of PHB/PVA in the compositions (w/w) 90/10, 75/25 and 50/50, and plasticized with glycerol were prepared by mechanical mixing using a single screw extruder. Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), dynamic-mechanical thermal analysis (DMTA) and scanning electron microscope (SEM) were used to study the miscibility of the blends. The main results indicate that the blends are miscible: i) shifted bands in FTIR spectrum of the blends in 1277 and 1054 cm-1 indicating strong intermolecular interactions in the system, such as polar and hydrogen bonds; ii) single Tg for the blends and intermediate between those of the pure component polymers observed on the DMTA curves; and iii) absence of two phases in the SEM images of blend with 90% PHB after extraction in aqueous medium of the possible PVA-rich phase. It was also possible to observe that the PHB crystallinity was not significantly affected by the addition of PVA as shown in the results of DSC and x-ray diffraction.
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Blendas ternarias PPO/AES/PS : estudo da miscibilidade, compatibilidade e estabilidade fotooxidativa / Ternary blends of PPO/AES/PS : study of the miscibility, compatibility and photooxidative stabilityTurchet, Renato 22 September 2006 (has links)
Orientador: Maria Isabel Felisberti / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-07T19:58:46Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: O objetivo deste trabalho foi preparar e avaliar o comportamento de blendas ternárias PPO/AES/PS com relação aos aspectos de miscibilidade, compatibilidade, propriedades mecânicas e estabilidade fotoquímica, bem como comparar estas propriedades com as das blendas PPO/HIPS. Neste trabalho as blendas ternárias PPO/AES/PS foram elaboradas a partir da mistura mecânica no estado fundido de PS, poliestireno, PPO, poli(2,6-dimetil-1,4-óxido de fenileno) e AES, um elastômero termoplástico obtido pela enxertia de SAN, poli(estireno-co-acrilonitrila) no EPDM, poli(etileno-co-propileno-co-5-etilideno-2-norboneno). Foram preparadas três séries de blendas ternárias, contendo respectivamente 40, 50 e 60 % de PPO. Em cada série variou-se a fração mássica do AES de 10, 15, 20 e 30 %. Para fins de estudos comparativos, também foram preparadas as blendas binárias PPO/AES, PPO/PS e AES/PS na composição 50/50 e as blendas binárias de PPO e poliestireno de alto impacto, HIPS, contendo o mesmo teor de PPO que as blendas ternárias. A análise dinâmico-mecânica das blendas ternárias revelou um comportamento de fases complexo, sendo possível verificar a existência de uma fase elastomérica de EPDM dispersa em uma matriz constituída por várias fases, sendo uma delas a mistura miscível PPO/PS. Tal comportamento deve-se ao fato do PPO e PS serem totalmente miscíveis, já o PS é miscível com SAN quando este contém menos que 5% em massa de acrilonitrila, e o PPO é miscível com SAN quando este contém menos que 10% em massa de acrilonitrila. As blendas ternárias apresentam propriedades mecânicas dependentes do teor de AES. O aumento do teor de AES promoveu um significativo aumento na resistência ao impacto com ligeira queda no módulo e na resistência à tração. Entretanto, somente algumas composições apresentaram desempenho mecânico superior às blendas PPO/HIPS. Ensaios de envelhecimento acelerado mostraram que as blendas ternárias são mais estáveis que as blendas PPO/HIPS que possuem uma fase elastomérica insaturada / Abstract: The aim of this work was to prepare and to evaluate the PPO/AES/PS ternary blends behavior with respect to miscibility, compatibility, mechanical properties and photochemical stability aspects, as well as to compare these properties to the PPO/HIPS blends. In this work, the PPO/AES/PS ternary blends were obtained from the melt mixture PS, polystyrene, PPO, poly(2,6-dimethyl-1,4-phenylene oxide), AES, a thermoplastic elastomer constituted by a grafting of SAN, poly(styrene-co-acrylonitrile), on EPDM, a poly(ethylene-co-propylene-co-diene) elastomer.Three series of the ternary blends containing 40, 50 and 60 % of PPO were prepared. In each ternary blends series the AES¿s mass fraction variation was 10, 15, 20 and 30 %. To perform a comparative study, the binary blends PPO/AES, PPO/PS and AES/PS, with composition 50/50%, and the PPO/HIPS binary blend with the same PPO¿s contents that the ternary blends, were also prepared. The dynamical mechanical analysis of the ternary blends showed a complex phases behavior, with the EDPM elastomeric phase dispersed in a matrix constituted by several phases, one of them the miscible blend PPO/PS. Such behavior is due to the fact that PPO and PS blends are miscible blends, while PS is only miscible with SAN when it contains less than 10 % wt of acrylonitrile and PPO/SAN blends are also miscible if the acrylonitrile composition is less than 5 wt %. The ternary blends presents mechanical properties dependent on the blend AES content. The increase in the AES content in the blends resulted in a significative increase in the impact resistance and a slight drop in the modulus and tensile resistence. However, only some compositions showed better mechanical performance than PPO/HIPS blends. Accelerated aging showed that the ternary blends are more stable than the PPO/HIPS blends that present an unsaturated elastomeric phase / Doutorado / Físico-Química / Doutor em Quimica
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The miscibility and viscoelastic behavior of liquid crystal polymers in nematic solventsChen, Fu-Lung January 1994 (has links)
No description available.
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Compatibilisation of polysulphones/polyester blendsMartin, Lee January 1994 (has links)
Ternary blends comprising Polysulphones [Polyethersulphone (PES) and Polysulphone (PSO)], the Polyhydroxyether of bisphenol-A (Phenoxy), and Polyesters [Poly( ethylene terephthlate) (PET) and Poly(butylene terephthlate) (PBT)] have been studied particularly with the aim in mind of elucidating the factors determining their miscibility and morphology. Binary and ternary combinations, including equivalent systems based on a butylene terephthlate-tetramethylene oxide block copolymer (PBT-TMO), were prepared from solution and by mixing in the melt state using both an internal mixer and a twin screw extruder. Scanning electron microscopy was employed to examme the morphology of these blends. A co-continuous, (interpenetrating), dual-phase morphology was displayed by both the PSO/PBT and PSO/PBT-TMO (70/30) combinations. The compatibility was further increased by the addition of Phenoxy, which was evidenced by the formation of a very fine dispersion of the two phases for both PSO/Phenoxy/PBT and PSO/Phenoxy/PBT-TMO blends, in the weight ratio of (60/15/25). A lower level of compatibility was displayed by the equivalent blends based on PES and PET, as a matrix/dispersed particle type of morpholgy was usually observed. Differential thermal analysis and dynamic mechanical analysis measurements were also employed to ascertain the level of miscibility in these systems. A single composition dependent glass transition temperature was displayed by the binary PBT/Phenoxy and PBT-TMO/Phenoxy melt blends, and the binary PES/Phenoxy and _PSO/Phenoxy solution blends. The remaining blends displayed two separate glass transition temperatures that were often broader and closer together than those of the homopolymers. This effect was more significant for blends containing the Phenoxy compatibiliser, confirming that these systems are semi-miscible. Solvent resistance measurements were made on 500μm thick extruded sheets by measuring the time to failure at stress levels corresponding to 30% and 50% of the tensile strength. The blends displaying a matrix/dispersed particle type of morphology revealed poor solvent resistance and mechanical properties. The blends displaying a cocontinuous interpenetrating dual-phase morphology on the other hand displayed a much higher solvent resistance and enhanced mechanical properties.
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Etude de la miscibilité des polymères par la méthode de coalescence des grains en vue du recyclage des DEEE par rotomoulage / Study of the miscibility of polymers using the sintering method to recycl WEEE polymers by rotomouldingAid, Sara 15 December 2017 (has links)
L’objectif de cette thèse est d’investiguer la miscibilité des mélanges de polymères dans une perspective de recycler les polymères issus des DEEE par rotomoulage. En effet, la miscibilité est un facteur clé qui conditionne les propriétés finales du mélange. Basé sur les résultats de caractérisation des flux DEEE d’Éco-systèmes, le choix des matériaux d’étude (PVDF/PMMA) et (ABS/PC) a été motivé par l’intérêt à la fois industriel et scientifique de ces deux couples. La première partie du travail présente une panoplie de méthodes expérimentales mises en place, allant des procédés de mise en œuvre à la caractérisation des matériaux dans le but d’explorer in fine la miscibilité de ces mélanges. En particulier, l’étude de la coalescence des grains a permis de mettre en évidence la miscibilité du couple PVDF/PMMA et la miscibilité partielle de l’ABS/PC (phénomène d’enrobage). À l’issu de cette étude, le couple PVDF/PMMA a été retenu en tant que couple « modèle » pour mettre en place un modèle prédictif généralisé de la coalescence entre grains de polymères différents. Ce modèle a été couplé à une étude probabiliste paramétrique des incertitudes permettant d’évaluer l’effet des incertitudes des mesures relatives à la viscosité, la tension de surface, le temps de relaxation et la taille des grains sur la cinétique de coalescence. Le travail se termine par une ébauche de la simulation du phénomène de coalescence et de l’enrobage dans le cas des polymères miscibles et partiellement miscibles. / The aim of this thesis is to study the miscibility of polymer blends with a view to recycling WEEE polymers by rotomoulding. Indeed, miscibility is a key factor which determines the final properties of polymer blends. The work was divided into two parts. Based on the characterization results of Éco-systèmes WEEE, the choice of materials (PVDF / PMMA) and (ABS / PC) was motivated by the industrial and scientific interest of these two couples. The first part of the work presents an array of experimental methods, ranging from processing to material characterization, with the aim of exploring the miscibility of these mixtures. In particular, the study of the coalescence of the grains made it possible to demonstrate the miscibility of the PVDF / PMMA couple and the partial miscibility of the ABS / PC (coating phenomenon). At the end of this study, the PVDF / PMMA couple was retained as a "model" pair to perform a generalized predictive model of the coalescence between different polymer grains. This model was coupled with a probabilistic parametric analysis to evaluate the effect of the uncertainties of the viscosity, surface tension, relaxation time and grain size measurements on coalescence kinetics. The work ends with a draft of the simulation of the coalescence phenomenon and the coating in the case of miscible and partially miscible polymers respectively
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Compatibilização de blenda polimérica de poliamida 6,6/ polietileno de baixa densidade utilizando radiação ionizante de feixe de elétrons / Compatibilization of Polyamide 6.6 and Low Density Polyethylene Polimeric Blend Using Electron Beam Ionizing Radiation.Feitosa, Marcos Antonio Fernandes 12 January 2009 (has links)
A indústria de plástico tem reconhecido que novos materiais podem ser produzidos por meio da mistura de polímeros dando origem às chamadas blendas poliméricas. Estes materiais, em geral, apresentam uma melhoria das propriedades em relação às dos polímeros que formam a blenda. Freqüentemente, as blendas são produzidas a partir de polímeros imiscíveis, os quais apresentam fases, microestruturas ou morfologias diferentes. A melhoria da miscibilidade entre os componentes da blenda, o que leva a um melhor desempenho, denomina-se compatibilização. Esta compatibilização pode ser feita por meio de processos químicos ou utilizando radiação ionizante. O presente trabalho tem como objetivo central o estudo do efeito da radiação ionizante de feixe de elétrons na blenda polimérica formada por poliamida PA 6,6 e polietileno de baixa densidade PEBD na proporção, respectivamente, de 75%/25% em peso, quando esta é submetida a diferentes doses de radiação no intervalo entre 50 kGy e 250 kGy. O efeito da compatibilização, induzida pela radiação ionizante, foi avaliado por meio de ensaios mecânicos que mostraram uma melhoria nas suas propriedades de tração e dureza e pela diminuição da resistência ao impacto das amostras irradiadas. Este comportamento mecânico pode ser atribuído à ação combinada da reticulação induzida na estrutura molecular dos polímeros que formam a blenda e ao aumento da miscibilidade destes componentes na blenda irradiada. O grau de compatibilização induzido pela radiação ionizante foi avaliado determinando-se as temperaturas de transição vítrea (Tg) dos componentes da blenda por meio de análise dinâmico mecânica (DMA). Dos resultados obtidos constatou-se que os valores de Tg dos polímeros PA 6,6 e PEBD se aproximaram em 8ºC, indicando que a radiação ionizante produziu efeito de compatibilização na blenda irradiada. / The plastic industry has recognized that mixture of polymers, called polymeric blends, yields new materials with improve properties and better features of those of the polymer blended. In most of the cases, blends are formed by immiscible components presenting separated phases, micro-structures or morphologies. One of the main factors for good mechanical performance is the interfacial adhesion of the blend components. The improvement of miscibility between the polymer components and the enhancement of blend performance is denominated of compatibilization. This compatibilization can be achieved by chemical methods or using ionizing radiation. The present work has as a main objective the study of the effect of the ionizing radiation from electron beam in the compatibilization of the polyamide (PA) 6.6 and low density polyethylene (LDPE) 75%/25% wt blend, in the range of applied doses from 50 to 250 kGy. The compatibilization effect was evaluated by mechanical test, which has shown improvement in the tensile strength and hardness properties and a reduction of the impact resistant. This mechanical behavior can be considered as a combination effect of the cross-linking, induced in the molecular structure on the polymers, and the increase of the miscibility of the blend components. The degree of compatibilization was evaluated by the behavior of the glass transition temperatures (Tg) for the blend components obtained by dynamic mechanical analysis (DMA) measurements. The results have shown that the values of Tg for PA 6.6 and LDPE get near by 8oC, showing that the ionizing radiation have promoted a compatibilization effect on the irradiated blend.
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Microfluidic Analysis for Carbon ManagementSell, Andrew 28 November 2012 (has links)
This thesis focuses on applying microfluidic techniques to analyze two carbon management methods; underground carbon sequestration and enhanced oil recovery. The small scale nature of microfluidic methods enables direct visualization of relevant pore-scale phenomena, enabling elucidation of parameters such as diffusion coefficients and critical compositions. In this work, a microfluidic platform was developed to control a two-phase carbon dioxide (CO2)-water interface for diffusive quantification with fluorescent techniques. It was found that the diffusion coefficient of CO2 in pure water was constant (1.86 [± 0.26] x10-9 m2/s) over a range of pressures. The effects of salinity on diffusivity were also measured in solutions, it was found that the diffusion coefficient varied up to 3 times. A microfluidic technique able to determine the critical composition of a model ternary mixture was also successfully implemented. Results indicate potential application of this approach to minimum miscibility pressure measurements used in enhanced oil recovery.
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Microfluidic Analysis for Carbon ManagementSell, Andrew 28 November 2012 (has links)
This thesis focuses on applying microfluidic techniques to analyze two carbon management methods; underground carbon sequestration and enhanced oil recovery. The small scale nature of microfluidic methods enables direct visualization of relevant pore-scale phenomena, enabling elucidation of parameters such as diffusion coefficients and critical compositions. In this work, a microfluidic platform was developed to control a two-phase carbon dioxide (CO2)-water interface for diffusive quantification with fluorescent techniques. It was found that the diffusion coefficient of CO2 in pure water was constant (1.86 [± 0.26] x10-9 m2/s) over a range of pressures. The effects of salinity on diffusivity were also measured in solutions, it was found that the diffusion coefficient varied up to 3 times. A microfluidic technique able to determine the critical composition of a model ternary mixture was also successfully implemented. Results indicate potential application of this approach to minimum miscibility pressure measurements used in enhanced oil recovery.
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Mouillabilité et miscibilité des bitumes : application au recyclage / Wettability and miscibility of bituminous binders : recycling applications for pavement materialsVassaux, Sabine 27 November 2017 (has links)
Le recyclage des matériaux routiers constitue une voie de développement durable qui présente des bénéfices en termes de consommation d’énergie et de ressources non renouvelables. Pour mieux prédire les propriétés finales de ces matériaux, la compréhension des phénomènes de mélange intervenant lors de la fabrication des enrobés à chaud et à tiède en centrale d’enrobage est indispensable. L’objectif de la thèse est donc de comprendre et d’identifier les facteurs influençant les phénomènes de mouillage, de remobilisation et de miscibilité des liants bitumineux. Pour cela, la démarche d’étude choisie consiste à étudier les interactions locales entre les constituants organiques et inorganiques du mélange selon une approche physico-chimique aux interfaces et interphases. Concernant le mouillage, des indicateurs ont été sélectionnés pour suivre son évolution à l’interface bitume/roche polie. L’influence du vieillissement du liant a aussi été prise en compte. La viscosité et le taux d’asphaltènes des bitumes ainsi que la composition de surface du substrat minéral influencent la qualité de mouillage. Les résultats ont montré que les évolutions étaient régies par un modèle applicable aux surfaces polies, poreuses et chimiquement hétérogènes. La remobilisation du liant vieilli (à température réduite) par le liant d’apport (chauffé à 160°C) a été étudiée à l’interface et à l’interphase sur des échantillons « bitume d’apport/bitume vieilli ». A l’interface, le temps d’étalement est influencé linéairement par la viscosité du liant vieilli. Concernant l’interphase, l’analyse des échantillons bitumineux a montré qu’une diminution de l’écart de températures entre les liants conduit à un meilleur mélange. Des méthodologies ont été développées pour suivre la migration du liant vieilli au moyen de techniques comme la micro fluorescence X, la microscopie infrarouge en mode ATR et en mode d’imagerie ATR. La microscopie infrarouge en mode d’imagerie ATR est particulièrement adaptée pour étudier la remobilisation du bitume vieilli à l’aide de la fonction carbonyle qui résulte de l’oxydation du bitume et traduit son état de vieillissement. Les résultats ont permis de déterminer les paramètres influents tels que la viscosité et la nature du liant vieilli ainsi que l’effet bénéfique d’un produit « régénérant » sur la remobilisation. L’effet d’une énergie d’agitation mécanique améliore également le mélange des liants. Concernant les résultats obtenus par micro fluorescence X, des éléments métalliques entrant dans la composition du bitume ont été choisis comme traceurs internes pour suivre la migration d’un liant. Des hypothèses ont été proposées pour expliquer les différences de migration des traceurs observées. Enfin, l’ensemble des méthodologies développées à l’échelle des liants a été appliqué à l’étude des produits routiers incorporant des granulats neufs et vieillis. Les résultats montrent une cohérence entre les tendances observées à l’échelle microscopique et macroscopique. Le procédé de fabrication à chaud favorise la remobilisation tandis que l’augmentation du taux d’agrégats d’enrobé le freine. L’augmentation du taux d’agrégats réduit également l’homogénéité du mélange bitumineux fabriqué qui a été évaluée au travers de la répartition spatiale de la fonction carbonyle, obtenue par un traitement statistique des cartographies chimiques par microscopie infrarouge. / In the road industry, the main challenge is to produce warm-mix asphalt mixtures while incorporating high rates of reclaimed asphalt, which come from the deconstruction of old pavement. However, the combination of recycling and the reduction of mix manufacture temperatures (warm mixes) raises technical issues about performance and durability of final pavement materials. In order to better predict final properties of these recycled materials, it is also necessary to understand phenomena occurring during the manufacture of recycled asphalt mixtures in the plant. The objectives of the PhD thesis are to understand and identify factors impacting wetting, remobilization and miscibility phenomena existing between organic and inorganic constituents of the bituminous mixture happening during the manufacturing step. The selected experimental approach consists in studying materials interactions according to a physicochemical approach at interfaces and interphases.Concerning wetting mechanisms at the “bitumen/aggregate” interface, some indicators were selected to assess wetting evolutions on a polished mineral slide. The binder ageing influence has also been studied. The bitumen viscosity and asphaltene content influence the wetting quality as well as the surface composition of the mineral substrate. Results have shown that “bitumen/aggregate” wetting evolutions were governed by a model associated to polished, porous and chemically heterogeneous surfaces.Remobilization of the aged binder (at a lower temperature) by the virgin one (heated at 160°C) has been studied at the interface and at the interphase of “aged binder/virgin binder “samples. At the bituminous interface, the spreading time is linearly influenced by the aged binder viscosity. At the bituminous interphase, bituminous sample analysis has shown that a reduction in the binders temperature difference leads to a better blend. Methodologies have been developed to monitor the aged binder migration using techniques such as X-ray micro fluorescence, infrared microscopy in ATR mode and in imaging ATR mode. Infrared microscopy in imaging ATR mode is a suitable technique to monitor the aged binder migration coupled to the carbonyl function marker resulting from the bitumen oxidation and ageing. Results have identified influent parameters corresponding to the aged binder viscosity and chemical composition, as well as the beneficial effect of a rejuvenator on remobilization. The effect of mechanical agitation energy also improves the binders blend. Concerning X-ray micro fluorescence results, binders remobilization has been assessed by the migration of metals which are involved in the bitumen internal composition. Some hypotheses have been proposed to explain observed migration differences of studied markers.Finally, all customized binder-scale methodologies have been applied to the study of road products incorporating virgin aggregates and reclaimed asphalt pavement. Results have shown similarities between observed trends at the microscopic and macroscopic scales. The hot manufacturing process promotes remobilization while the increase in the reclaimed asphalt rate limits it. The increase in the reclaimed asphalt rate also reduces the asphalt mixture homogeneity degree which has been evaluated through the carbonyl function spatial distribution, obtained by a chemical mappings statistical treatment.
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