Made available in DSpace on 2016-12-08T17:19:26Z (GMT). No. of bitstreams: 1 Marindia Decol.pdf: 3575085 bytes, checksum: bed6c0ed662d3c76c64b6cfdac902d8b (MD5) Previous issue date: 2015-07-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Poly (lactic acid) (PLA) is a rigid and brittle thermoplastic polymer, and poly (ε-caprolactone) (PCL) is a thermoplastic polymer of lower rigidity and higher toughness than PLA. Combination of these properties through the blend PLA/PCL has been studied successfully to change the final properties of the PLA. The addition of multiwalled carbon nanotubes (MWCNT) in the blend PLA/PCL may induce peculiar orphologies depending on their location, resulting in the getting new properties or modifying the properties of the PLA matrix. This study aimed to evaluate the effect of adding the PCL, the compatibilizer Cesa-mix and MWCNT the final properties of the PLA. Mixtures were prepared in internal mixer chamber coupled to a torque rheometer and subjected to characterizations of morphological, thermal, mechanical and electrical properties. In the morphological analysis, there was a 37% reduction in the average size of the phases of the PCL blends PLA/PCL with the addition of compatibilizer Cesa®- mix, a heterogeneous distribution of MWCNT the PLA matrix and a selective location of MWCNT in phase PCL. With respect to thermal properties, the addition of the compatibilizing PCL and did not significantly affect the thermal degradation onset temperature (Tonset) of the PLA, but the addition of the MWCNT in PLA resulted in decreased Tonset nanocomposites. The melting temperature did not change significantly with the addition of PCL, the compatibilizer and MWCNT on the PLA matrix. Already cold crystallization temperature decreased and the degree of crystallinity of the PLA increased with the addition of PCL blends and MWCNT in nanocomposites. Decreases of 35% on elastic hardness and 29% in modulus of elasticity was observed with the addition of PCL and compatibilizer Cesa®-mix in the blends PLA/ PCL/AC/2,5%. With the addition of MWCNT was observed an increase of 6,8% on elastic hardness and 8% in the modulus of elasticity of PLA/CNT mixtures with 1,0% w/w. Blends of PLA/PCL with 0,5% and 1,0% w/w CNT with and without compatibilizer, had a decrease in modulus of elasticity and elastic hardness. No significant changes were observed in the electric resistance of the samples with the addition of the compatibilizer, the PCL and MWCNT with 0,5% and 1,0% w/w. Selective location of MWCNT the PCL phase had great influence on morphological, thermal, mechanical and electrical properties of nanocomposites. / O poli(ácido lático) (PLA) é um polímero termoplástico rígido e frágil, e a poli(ε-caprolactona) (PCL) é um polímero termoplástico de menor rigidez e maior tenacidade que o PLA. A combinação destas propriedades através da blenda PLA/PCL tem sido estudada com êxito no auxílio à alteração das propriedades finais do PLA. A adição de nanotubos de carbono de paredes múltiplas (NTCPM) na blenda PLA/PCL pode induzir a morfologias peculiares dependendo da sua localização, resultando na obtenção de novas propriedades ou na alteração das propriedades da matriz PLA. Este trabalho teve como objetivo avaliar o efeito da adição do PCL, do compatibilizante Cesa-mix e dos NTCPM nas propriedades finais do PLA. As misturas foram preparadas em misturador de câmara interna acoplado a reômetro de torque e submetidas à caraterizações das propriedades morfológicas, térmicas, mecânicas e elétricas. Na análise morfológica, observou-se uma redução de 37% no tamanho médio das fases de PCL nas blendas PLA/PCL com a adição do compatibilizante Cesa®- mix, uma distribuição heterogênea dos NTCPM na matriz PLA e uma localização seletiva dos NTCPM na fase PCL. Em relação às propriedades térmicas, a adição do PCL e do compatibilizante não afetaram significativamente na temperatura de início de degradação térmica (Tonset) do PLA, porém a adição de NTCPM no PLA resultou em decréscimo na Tonset dos nanocompósitos. A temperatura de fusão não apresentou variação significativa com a adição do PCL, do compatibilizante e dos NTCPM na matriz PLA. Já a temperatura de cristalização a frio diminuiu e o grau de cristalinidade do PLA aumentou com a adição de PCL nas blendas e dos NTCPM nos nanocompósitos. Diminuições de 35% na dureza elástica e de 29% no módulo de elasticidade foram observadas com a adição do PCL e do compatibilizante Cesa®-mix nas blendas PLA/PCL/AC 2,5%. Com a adição de NTCPM foi observado um aumento de 6,8% na dureza elástica e de 8% no módulo de elasticidade das misturas PLA/NTC com 1,0% m/m. As misturas de PLA/PCL com 0,5% e 1,0% m/m de NTC com e sem compatibilizante, tiveram um decréscimo no módulo de elasticidade e na dureza elástica. Não foram verificadas alterações significativas na resistência elétrica das amostras com a adição do compatibilizante, do PCL e dos NTCPM com 0,5% e 1,0% m/m. A localização seletiva dos NTCPM na fase PCL teve grande influência nas propriedades morfológicas, térmicas, mecânicas e elétricas dos nanocompósitos.

Made available in DSpace on 2016-12-08T17:19:35Z (GMT). No. of bitstreams: 1 Tatiana da Cunha Gomes Leitzke.pdf: 2438825 bytes, checksum: 8c0dbce0f01fadf8eb99d5b68ba3e534 (MD5) Previous issue date: 2003-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aiming the development of polymer materials with high toughness, poly(butadiene-coacrylonitrile) rubbers (NBRs), with acrylonitrile (AN) contents varying from 32,9 to 45,7%, were added to poly(styrene-co-acrylonitrile) (SAN) by casting, mini-extrusion and monoscrew extrusion followed by injection molding. Addition of NBR resulted in significant improvements in the impact strength and the elongation at break, that were strongly influenced by the blend composition, the AN contents and the NBR melt viscosities, but the tensile strength is slightly decreased. The best impact strength results (157,1 ± 3.7 J/m) were obtained with a 70/30 (w/w) SAN/NBR blend using NBR with 33,1% of AN and 51 ML 1+4 (100°C), being ca. 700% higher than the values for pure SAN (22,4 ± 1.1 J/m). Differential scanning calorimetry (DSC) measurements indicated a partial miscibility between the copolymers, showing a shifting of the SAN glass transition temperature from 108,1 to 101,7oC for the 70/30 blend with NBR containing 45,7% of AN. This is in agreement with infrared spectroscopy (FTIR) analysis that displayed a significant shift of the dienic band from 967 cm-1 to ca. 1060 cm-1 for all 70/30 blends, suggesting segmental interactions between NBR and SAN. Scanning electron micrographs (SEM) from fracture surfaces revealed homogeneously dispersed spherical elastomeric domains, and the appearance of yielding and/or crazing processes for all blends. The size of NBR domains decreased as the AN content increased, while the number of NBR domains decreased as the melt viscosity increased. From these results it can be concluded that SAN thoughening by the addition of NBR is directly related to the AN content and the melt viscosity of the elastomer, depending on the morphology of the dispersed rubber phase. Higher NBR domain sizes cause better impact strengths, as large rubber particles are more effective in initiating crazing processes. / Com o objetivo de desenvolver materiais poliméricos com elevada tenacidade, borrachas de poli(butadieno-co-acrilonitrila) (NBR), com teores de acrilonitrila variando de 32,9 a 45,7%, foram incorporadas ao poli(estireno-co-acrilonitrila) (SAN), por evaporação desolventes, mini-extrusão e extrusão seguida de injeção. A adição do NBR resultou em um aumento significativo na resistência ao impacto e na deformação na ruptura, que foram fortemente influenciadas pela composição da blenda, pelo teor de acrilonitrila e pela viscosidade dos NBRs, porém, houve a diminuição da resistência à tração. O melhor resultado de resistência ao impacto (157,1 ± 3.7 J/m) foi obtido para a blenda 70/30 (m/m) utilizando NBR com 33,1% de acrilonitrila e 51 ML 1+4 (100°C), um valor cerca de 700% maior que o verificado para o SAN puro (22,4 ± 1.1 J/m). A técnica de calorimetria diferencial de varredura (DSC) indicou uma miscibilidade parcial entre os copolímeros, mostrando o deslocamento da temperatura de transição vítrea do SAN de 108,1 a 101,7ºC para a blenda 70/30 utilizando o NBR com 45,7% de acrilonitrila. Este resultado concorda com a análise de espectroscopia de infravermelho (FTIR), que mostrou um deslocamento significativo da banda da parte butadiênica de 967 cm-1 para 1060 cm-1, para todas as blendas 70/30, sugerindo assim interações segmentais entre o NBR e SAN. A análise da superfície de fratura por microscopia eletrônica de varredura (MEV), revelou homogeneidade dos domínios elastoméricos dispersos na matriz, bem como o aparecimento de microtrincas e/ou deformação plástica para todas as blendas. O tamanho dos domínios de NBR diminui com o aumento do teor de acrilonitrila presente no NBR, enquanto a quantidade de domínios diminui com o aumento da viscosidade. A partir destes resultados conclui-se que a tenacificação do SAN com a adição de NBR está diretamente relacionada com o teor de acrilonitrila e viscosidade do elastômero e depende da morfologia da fase elastomérica dispersa na matriz. Os domínios maiores de NBR proporcionaram melhor resistência ao impacto, sendo que partículas de borracha maioresfavorecem o aparecimento de microtrincas.

Motor a álcool teve grande aplicação no Brasil com a implantação do Proálcool, programa lançada na década de 1970, vislumbrando reduzir a dependência externa do petróleo. Ressalta-se que avanços na tecnologia do referido motor, bem como na produção de álcool, tornaram-no técnica e economicamente viável como substituto da gasolina em algumas regiões. O presente trabalho teve por objetivo avaliar o desempenho e a emissão de um motor ciclo Otto funcionando com dois tipos de álcool, 92,8 e 75 INPM, sendo o último considerado de baixo teor alcoólico, possibilitando variar a taxa de compressão. O ensaio foi realizado em bancada dinamométrica, no laboratório de motores da EESC/USP, campus de São Carlos. Para tanto, utilizou-se de motor de 1.000 \'CM POT.3\', oito válvulas e quatro cilindros. Os resultados evidenciaram que o combustível de baixo teor alcoólico aceitou aumento na taxa de compressão de 13,5:1 para 16,2:1, ressaltando-se que, nessa condição, houve aumento de torque e da potência máxima, redução de emissão de NOx e aumentos de consumo e de emissão de hidrocarboneto. / Ethanol engines had a great application in Brazil with the implantation of Proalcool, a program launched in 1970 decade, guessing the reduction in exterior oil dependence. Progress in technology in the cited engine, as well as in ethanol production have turned this combustible into a technically and economically viable option, as an oil substitute in some regions. The present work had the aim of evaluating the performance and emission of an Otto cycle engine working with two types of ethanol, 92.8 and 75 INPM, the latter considered as a low grade alcohol, enabling a variation in the compression rate. The experiment was performed at the dynamometer testing bench in the engine laboratory of EESC/USP, campus at São Carlos. With this intent a 1,000 \'CM POT.3\' engine, eight valves and four cylinders were utilized. The results have shown that the low grade alcoholic combustible accepted an enhancement in the compression rate from 13.5 to 16.2:1, emphasizing that in this condition there was increase maximum torque and maximum power, a reduction in NOx emission and a rise in the consumption and hydrocarbon emission.

This work presents the use of analytical techniques, conventional and advanced for the chemical characterization of four samples of blends crude oils from the PETROBRAS station, Oiteirinhos II (Carmópolis-SE). These samples, which have different exploration characteristics, were identified as CEOL 1, CEOL 2, CEOL 3 and CEOL 4. After the collection in the field and subsequently separation of water residue through centrifugation at 2500 rpm, the blends were characterized by density, asphaltenes content, fractionation SARA (saturates, aromatics, resins and asphaltenes) and by the application of micropyrolisys off-line. The advanced characterization to elucidate the chemical relationship between the samples were made using the Thermogravimetry (TGA), Infrared Spectroscopy (IR), Spectroscopy in Ultraviolet (UV), Matrix Assisted Laser Desorption Ionization - Time of Flight - Mass Spectrometry (MALDI-TOF-MS), Gas Chromatography Mass Spectrometry (GC/MS), Gas Chromatography with Flame Ionization Detector (GC-FID) and Comprehensive Two-Dimensional Gas Chromatography (GC x GC). The blends CEOL 3 presented the highest density (0.9737 g mL-1), confirming the results of MALDI-TOF-MS, that shows predominantly high molecular mass compounds in the composition. The SARA fractionation indicates the Saturated fraction as the largest fraction in all oils (> 50%). The analysis of TGA explained similar bands of mass loss in all blends and their asphaltenes. The characterization by IR showed bands related to the hydrocarbon composition and the UV showed the presence of mono, di and tri aromatics structures in the blends as well in their respective asphaltenes. The chromatographic analysis (GC/MS, GC-FID and GC x GC) showed that all blends have a paraffinic profile, with the predominance of n-alkanes of low molecular weight (n-C10 to n-C40) and characteristics of oxide depositional environment (Pr/Ph>1) and lacustrine origin (CPI>1). The analysis by GC/MS showed that the distribution area relating to the free n-alkanes in the CEOL 3 blends is approximately 30% lower than the other samples, and that after the micropyrolysis process these areas become approximately the same. For biomarkers, GC/MS was possible to identify the majority presence of tri- and tetracyclic terpanes (m/z 191) and regular steranes (m/z 217) as the major constituents of the blends, pointing also to the release of occluded biomarkers in asphaltenic structures after the micropyrolysis process. The identification and subsequent correlation between biomarkers indicated that the blends crude oils studied have partial biodegradation characteristics, with a blend of mature and immature oils from terrigenous and/or algal organic matter. / Este trabalho apresenta o emprego de diversas técnicas analíticas, convencionais e avançadas, para a caracterização química de quatro blendas de óleos brutos provenientes da estação da Petrobras de Oiteirinhos II (Carmópolis-SE). Estas amostras, que apresentam diferentes características de exploração, foram identificadas como CEOL 1, CEOL 2, CEOL 3 e CEOL 4. Após a coleta em campo e posterior separação dos resíduos de água por centrifugação a 2500 rpm, as blendas foram caracterizados a partir da determinação da densidade, do teor de asfaltenos, fracionamento SARA (Saturados, Aromáticos, Resinas e Asfaltenos) e aplicação da micropirólise off-line. A caracterização avançada, aplicada para elucidar a relação química entre as amostras, foram realizadas utilizando as técnicas de Termogravimetria (TGA), Espectroscopia no Infravermelho (IV), Espectroscopia no Ultravioleta (UV), Espectrometria de Massa por Tempo de voo com Desorção-Ionização a Laser Assistida por Matriz (MALDI-TOF-MS), Cromatografia Gasosa acoplada a Espectrometria de Massas (CG/EM), Cromatografia Gasosa com Detector de Ionização de Chama (CG-DIC) e Cromatografia Gasosa Bidimensional Abrangente (CG x CG). A blenda CEOL 3 apresentou a maior densidade (0,9737 g mL-1) corroborando com os resultados de MALDI-TOF-MS, mostrando a predominância de compostos de alta massa molecular em sua composição. O fracionamento SARA aponta a fração de Saturados como a maior fração em todos as blendas (>50%). A análise de TGA expôs faixas de perdas de massas semelhantes em todas as amostras e seus asfaltenos. A caracterização por IV apresentou estiramentos referentes à composição de hidrocarbonetos e o UV a presença de estruturas mono, di e tri aromáticos tanto nas blendas como em seus respectivos asfaltenos. As análises cromatográficas (CG/EM, CG-DIC e CG x CG) mostraram que todos as blendas possuem um perfil parafínico, com predominância de n-alcanos de baixo peso molecular (n-C10 a n-C40) com características de ambiente deposicional óxido (Pr/Ft>1) de origem lacustre (CPI>1). A análise por CG/EM mostrou ainda que a distribuição em área referente a n-alcanos livres presentes na blenda CEOL 3 é cerca de 30% menor do que as outras amostras, e que após o processo de micropirólise essas áreas passam a ser aproximadamente iguais. Para biomarcadores, por CG/EM foi possível identificar a presença majoritária de terpanos tri e tetracíclicos (m/z 191) e esteranos regulares (m/z 217), como constituintes majoritários das blendas em estudo, apontando ainda, a liberação de biomarcadores ocluídos nas estruturas asfaltênicas após o processo de micropirólise. A identificação e posterior correlação entre os biomarcadores indicaram que as blendas de óleos brutos possuem características de biodegradação parcial, com uma mistura de muito e pouco evoluídos termicamente, provenientes de matéria orgânicas terrígenas e/ou algas.

Neste trabalho estudou-se o comportamento reológico e morfológico da mistura polimérica imiscível de polipropileno e poliamida. Como resultado deste estudo obtiveram-se valores de tensão interfacial entre 10mN/m e 13mN/m. A tensão interfacial diminuiu em até 87% quando a mistura é compatibilizada com polipropileno maleado. A análise morfológica no regime de viscoelasticidade linear quando avaliada uma morfologia de emulsão de poliamida em polipropileno revelou diâmetro médio da fase dispersa entre 1,5µm e 20µm. O diâmetro das gotas da fase dispersa diminuiu com a adição de polipropileno maleado chegando a reduções de até 98%, mantendo-se constante a concentração da fase dispersa. No regime de viscoelasticidade não linear foram testados modelos para avaliar o comportamento da mistura em fluxos de cisalhamento e extensão, sendo que somente para os fluxos de extensão foi obtida boa correlação dos resultados experimentais com as previsões teóricas. / Rheological and morphological behaviour of polypropylene and polyamide polymer blend was studied. The values of interfacial tension were obtained between 10mN/m and 13mN/m. The interfacial tension decreased in 87% for compatibilized blend. Morphology analysis for linear viscoelastic regime shows dispersed drop diameter between 1,5µm and 20µm. The diameter of the drops decreased with the addition of maleic polypropylene reducing until 98%, keeping constant the concentration of the disperse phase. In non linear viscoelastic regime different models were tested to evaluate the behavior of the blends in shear and elongacional flows. However, only the elongacional flow results were acquired with theoretical - experimental corroboration.

Les boues de stations d’épurations sont un combustible difficile à valoriser par voie thermochimique à cause des fortes teneurs en eau, en azote et en fraction minérale. La co-gazéification avec d’autres gisements pourrait apporter une solution à ces contraintes. Afin d’étudier la faisabilité de ce procédé, un pilote industriel de de co-gazéification en lit fluidisé bouillonnant est conçu.Six co-combustibles potentiels ont été présélectionnés, à partir d’un large panel de gisements issus de la région PACA. La démarche expérimentale de ce travail concerne trois volets principaux qui consistent à :I. Etudier la faisabilité technique de co-gazéification à l’échelle laboratoire en vue de déterminer quel co-combustible est apte à compenser les faiblesses que présentent les boues.II. Contribuer à la définition des conditions opératoires de co-gazéification en lit fluidisé bouillonnant.III. Etudier le comportement en fluidisation des gisements sélectionné dans une maquette à température ambiante en mélange avec du sable.Les résultats indiquent que les tous les gisements retenus sont apte à être valorisés par co-gazéification. L’aptitude à la fluidisation des combustibles seuls est médiocre, l’utilisation de sable permet de l’améliorer. Un critère prédictif de la capacité maximale des lits fluidisés à contenir des déchets a été développé, une corrélation prédictive de la vitesse minimale de fluidisation de mélanges dissimilaires est également proposée. La teneur en combustible ne doit pas excéder les 10% en masse pour garantir une fluidisation correcte. Une vitesse de trois fois la vitesse minimale de fluidisation de l’inerte est la limite basse qui garantit un bon mélange. / The wastewater sludge composition (moisture, nitrogen and mineral matter content) leads to difficulties in disposal by thermochemical way. Co-gasification with other feedstock can improve the quality of the raw fuel gasification. In order to study the technical feasibility of wastewater sludge with other feedstock co-gasification, an industrial pilot scale bubbling fluidised bed co-gasifier is designed.Six potential co-feedstocks were preselected on technical and economic criteria, from a wide range of fields from the PACA region. The experimental approach of this work involves three main steps which are:I. The technical feasibility of co-gasification at laboratory scale, in order to identify which feedstock is able to compensate the sludge weaknesses.II. Identification of co-gasification conditions in fluidised bedIII. Cold fluidization ability study of the different feedstock blended with sand.The results indicate that all feedstock are recoverable through gasification. The fluidization ability of the fuel alone was poor, the blinding with sand improve it. A prediction criteria for the maximum capacity of fluidised bed of sand to improve the fluidization ability of waste is developed. A new correlation for minimum fluidization velocity is introduced. To obtain a correct fluidization the fuel concentration should be fixed below 10% by weight. The fluidization velocity should be fixed above three times sand minimum fluidization velocity to obtain a mixed bed.

Les Déchets d'Equipement Electriques et Electroniques (DEEE) constituent un volume important de déchets dont le constituant majoritaire est l’ABS. C’est pour cela que nous avons travaillé principalement avec des polymères provenant d’un gisement réel (carters d’ordinateurs). Puis, des mélanges ABS/PC ont été élaborés (le PC étant un des constituants d’un gisement de carters), dans le but d’obtenir un matériau avec une résilience au moins équivalente à celle d’un ABS neuf. Même si l’ABS a montré une bonne aptitude à être recyclé seul, après vieillissement et recyclage, sa résilience connaît une chute due à la dégradation de la phase élastomère et à la présence d’ignifugeants. Il est important pour le recyclage de l’ABS et de ses mélanges de séparer les polymères ignifugés de ceux qui ne le sont pas. La voie mélange pour le recyclage de l’ABS par l’ajout de PC a l’avantage de simplifier le tri et de recycler un maximum des polymères présents dans les DEEE. Nous avons tout d’abord réalisé des mélanges ABS/PC neufs pour bénéficier d’une mise en œuvre et d’une composition optimales. L’influence des paramètres du procédé de recyclage (température et vis d’extrusion) et des propriétés des matériaux (taux et viscosité du PC, retardateurs de flamme de l’ABS) sur les propriétés du mélange a été étudiée. Nous avons effectué essentiellement des essais de résistance au choc Charpy et des études morphologiques. Les résultats ont montré qu’une morphologie fibrillaire ou co-continue est favorable à la meilleure résilience des mélanges ABS/PC. Nous avons obtenu pour des mélanges neufs ABS neuf FR/PC neuf réalisés avec 70% d’ABS une résilience supérieure à celle de l’ABS neuf. Mais, à composition égale, ce résultat n’a pas été atteint pour les mélanges majoritaires en ABS recyclé. Souhaitant réaliser des mélanges performants majoritaires en ABS recyclé, la compatibilisation semble nécessaire. Un mélange recyclé majoritaire en ABS, compatibilisé avec du PP-g-MA, est montré plus résilient que l’ABS neuf seul. Toutefois, les compatibilisants ont une efficacité limitée lorsqu’ils sont en présence de retardateurs de flamme ou soumis à un temps de séjour élevé dans la presse à injecter. Nous avons voulu utiliser des nanocharges minérales (montmorillonites), ajoutées en faible quantité, en tant qu'ignifugeants et compatibilisants. Elles se sont avérées inefficaces dans les études préliminaires réalisées. Le choix des nanoargiles minérales doit être optimisé. / WEEE constitute a huge waste volume in which ABS is the major component. So, we focused on polymers from a real deposit (casing of computers); such a deposit contains ABS, PC, PS, ABS-PC. In a first step, recycling of aged ABS was studied. The decrease in the C=C content induces an impact strength drop. Nevertheless, ABS proved to be recyclable given that optimized processing conditions are found. The role of flame retardants was shown to be crucial on the recyclability. Separating polymers with or without flame retardants is the key point of the ABS recycling. However, recycled aged ABS do not recover the impact strength of neat virgin ABS. Then, ABS/PC blends were elaborated in order to obtain a material with an impact strength at least equivalent to the neat ABS. The use of ABS/PC blends for this recycling facilitates the sorting and the utilization of most of WEEE polymers. We first made ABS/PC blends from virgin polymers to have optimal processability and composition. Performing Charpy impact strength tests and morphological studies allowed to evaluate the influence of recycling process parameters (temperature and screw extrusion) and material properties (rate and viscosity of PC and ABS flame retardants). Experimental results indicate that the impact strength of the ABS/PC blends is higher when the morphology is fibrillar or co-continuous. We obtained ABS virgin FR/PC virgin blends (70/30) with an impact strength greater than the neat ABS. But, with equal composition, this result was not reached for the blends. So to achieve reliable blends rich in recycled ABS, compatibilisation is necessary. Recycled ABS/PC blends compatibilised with PP-g-MA is more resilient than the ABS. However, the compatibilising agents have a limited efficiency when they are used in the presence of flame retardants or subjected to a high residence time. Finally, nanoclays were attemptively used as both FR and compatibiliser. Tough they proved uneffective in the very first experiments carried out (the choice of clay need to be optimized).

Ces travaux menés à l’IMP@UJM ont pour objectifs la réalisation de films minces alimentaires 100% compostables par extrusion gonflage, thermoformage et biétirage. Des mélanges à base de farine plastifiée et de polyesters compostables ont été étudiés. La farine peut être déstructurée par extrusion bivis en présence de glycérol de manière similaire à l’amidon. La farine thermoplastique, ainsi obtenue, présente toutefois des différences notables avec l’amidon mais ne répond toujours pas aux applications visées. Son mélange avec des matrices polyester (PBAT et PLA) dans un procédé d’extrusion bivis a été réalisé et les morphologies caractérisées. La dispersion de la farine thermoplastique dans le PBAT, de type goutte / matrice, a été mise en étroite relation avec leur comportement rhéologique. Les propriétés mécaniques à l’état solide résultantes de ces mélanges ont été discutées en terme de microstructures, déformabilité de la phase dispersée et de l’adhésion à l’interface. Avec des charges modèles mélangées dans le PBAT et des analyses microscopiques sous déformation, le comportement mécanique de la phase dispersée a été clarifié. A l’état fondu, ces mélanges proposent des propriétés intéressantes mais limitées par les modifications de la matrice lors de son mélange avec la farine. Des défauts inhérents à la farine plastifiée et aux mélanges de polymères non compatibilisés ont été identifiés et une chimie adaptée a été développée. La polymérisation par ouverture de cycle du triméthylène carbonate à partir de fonctions hydroxyle en présence de catalyseurs organiques ou amorceurs organométalliques montre des cinétiques de réaction intéressantes pour un procédé d’extrusion réactive. Des fonctions hydroxyle modèle d’environnement chimique et stérique proche de l’amidon ont été utilisées pour l’amorçage de la polymérisation et les résultats ont été transposés aux fonctions hydroxyle de l’amidon, en présence ou non de glycérol. Une modification chimique de la farine thermoplastique, par greffage d’un polycarbonate, a donc été réalisée en extrusion réactive couplée au mélange avec le PBAT. Les effets compatibilisants ont ensuite été discutés en terme de microstructures, de réactions chimiques à l’interface farine plastifiée / PBAT et de modifications de la matrice PBAT. Les propriétés mécaniques de ces mélanges à l’état solide et fondu montrent des effets liés à la modification de l’interface / Thin compostable films for extrusion blowing, thermoforming and biaxial stretching are in the scope of these works. Blend of thermoplastic flour and compostable polyesters are proposed and studied. Corn flour can be processed in a twin-screw extruder with glycerol in a similar way than starch. Thermoplastic flour shows some differences with starch but still cannot be used in thin film applications. Thermoplastic flour was blended in a melt state with a compostable polyester matrix, PBAT. Matrix / particle morphologies were achieved and linked with individual rheological behaviour. Good global mechanical properties results from these morphologies were discussed in terms of microstructures, dispersed phase deformation under stress and interface properties. Model particles blends with PBAT and microscopical investigations confirmed the mechanical behavior of the dispersed phase. These blends still suffer from inherent problems concerning thermoplastic flour and uncompatibilized blends. A suitable chemistry was developed to overcome these defects based on monomer polymerization from starch. Ring opening polymerization of trimethylene carbonate in presence of hydroxyl functions and organic catalyst or organometallic initiators displays interesting reaction rates for a reactive extrusion process. Model co-initiators with chemical and sterical environments close to starch were used and transposed. Thermoplastic flour modification by polycarbonate grafting was achieved in a reactive extrusion process coupled with his blending in a melt state with PBAT matrix. Compatibilization effects were discussed in terms of microstructures, interface reactions and matrix modifications. Interface modifications were evidenced on mechanical properties of these blends

The master's thesis focuses on preparation of blown films from polylactid acid (PLA) which was blended with selected polyesteres – poly(butylene adipate-co-terephtalate) (PBAT), polycaprolactone (PCL) and polybutylene succinate (PBS) – and thermoplastic starch (TPS) in amount of 30% in order to soften PLA films. The influence of the aditives on static and mechanical tensile properties, on structure, morphology and thermal properties of the films was determined and the obtained parameters were compared to properties of films prepared from neat PLA and high density polyethylene (HDPE). The results showed that the additives increased crystalinity of PLA and thus significantly influenced the properties of the films. In contrast to the film from neat PLA, softening in terms of lowering glass transition temperature occured only by adding PBS and TPS, in terms of increasing ductility only by adding PBAT. All PLA films showed nearly constant elastic modulus up to the beginning of glass transition enabling their potential application till 50 °C. Preparation of the film with TPS was problematic and the film showed the worst mechanical properties. Preparation of other films was without any problems. The most promising additive from the tested ones was PBAT which showed comparable mechanical properties as the film from HDPE.

High molecular weight PBTTT-C₁₂ is blended with the pure trimer, BTTT-3, to enhance intergrain connectivity and charge transport. Analysis of the morphology and crystallinity of the blends shows that the polymer and oligomer are well-integrated, leading to high hole mobilities, greater than 0.1 cm² V⁻¹ s⁻¹, in films that contain as much as 83% oligomer.