Dissertations / Theses on the topic 'Polypropylene nanocomposite'
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Yilmaz, Sule Seda. "Preparation And Characterization Of Organoclay-polypropylene Nanocomposites With Maleic Anhydride Grafted Polypropylene Compatibilizer." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613291/index.pdf.
Full textMoplen&rdquo
EP300L which is a heterophase copolymer. Polymer blends and nanocomposites were prepared by melt compounding method in a twin screw extruder. Nanofil®
5 (N5) and Nanofil®
8(N8) were used as the organoclays, and maleic anhydride grafted polypropylene (M) was used as the compatibilizer. The effects of additive concentrations and types of organoclays on the morphology, mechanical and thermal properties were investigated. Organoclay loading over 2 wt% prevented the intercalation mechanism resulting in large aggregates of clay, thus the material properties became poor even in the presence of compatibilizer. Compatibilizer addition improved the intercalation ability of the polymer, however a substantial increase in mechanical properties was not obtained up to 6 wt % loading of the compatibilizer. XRD analysis revealed that intercalated structures were formed with the addition of compatibilizer and organoclay. The nanocomposites that were prepared with N5 type organoclay showed delaminated structures at 6 wt % compatibilizer loading. v Nanofill ®
5 exhibited the highest improvements in mechanical properties, since the degree of organoclay dispersion was better in Nanofill ®
5 containing nanocomposites in comparison to Nanofill ®
8 containing ones. The DSC analysis indicated a insignificant reduction in the melting temperature of the ternary nanocomposites.
Bondar, I. V., S. V. Kuzenko, D. H. Han, and H. K. Cho. "Synthesis of Polypropylene Fiber / Hydrated Iron Oxide Nanocomposite Adsorbent." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35589.
Full textCengiz, Filiz. "Preparation And Characterization Of Recycled Polypropylene Based Nanocomposites." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609873/index.pdf.
Full text15A, Cloisite®
25A and Cloisite®
30B were used as organoclays, and ethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) and maleic anhydride grafted polypropylene (PP-MAH) were used as compatibilizers. The effects of additive concentrations, types of organoclays and compatibilizers, processing conditions, and the compatibilizer to organoclay ratio on the morphology and mechanical, thermal and flow properties were investigated. Organoclay loading over 2 wt% prevented the intercalation mechanism and material properties, even in the presence of compatibilizer, as a consequence of large clay agglomerate formation. E-MA-GMA compatibilizer improved the intercalation ability of the polymer
however a substantial increase in mechanical properties was not obtained. PP-MAH is found to be a better compatibilizer. Processing conditions significantly affected both mechanical properties and morphology. When the processing temperature was decreased and screw speed was increased simultaneously, tensile and impact properties were improved owing to enhanced shear and dispersive forces. TEM analysis revealed that intercalated and delaminated structures were formed with the addition of PP-MAH compatibilizer. In addition to that, as the ratio of PP-MAH to organoclay was increased, more effective dispersion of organoclay was observed and hence resultant improvements in both tensile and impact properties were greater at compatibilizer to organoclay ratio of three. Cloisite®
15A exhibited the highest improvements in mechanical properties, although the degree of organoclay dispersion was better for Cloisite®
25A and particularly for Cloisite®
30B. Melt flow index values were lower compared to pure recycled polypropylene in the presence of organoclay and compatibilizers. DSC analysis indicated no significant change in the melting behavior of the matrix materials.
Woods, Courtney G. "Role of nano-particles on crystalline orientation in polypropylene/clay nanocomposite films." Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04072004-180242/unrestricted/woods%5Fcourtney%5Fg%5F200312%5Fms.pdf.
Full textBaytekin, Sevil. "Synthesis And Characterization Of Polypyrrole Nanoparticles And Their Nanocomposites With Polypropylene." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610563/index.pdf.
Full textBoruban, Cetin. "Synthesis And Characterization Of Polypyrrole/montmorillonite And Polypyrrole/polypropylene Composites." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608574/index.pdf.
Full text#8217
s Modulus of PPy/PP composites increased with increasing PPy content, and addition of 2 wt % PPy to PP resulted in a dramatic decrease in the tensile strain at break of the material. Also by addition of 2 wt % PPy to PP, the tensile strength of material decreased and further increase in PPy content, tensile strength increased. Furthermore, an increase in the PPy content in PPy/PP composites resulted in an increase in conductivity. SEM micrographs revealed that as the PPy loading increases from 10% to 20% in composite system, adhered PPy particles by PP matrix were driven out of PP matrix while PP matrix oriented along the draw direction during tensile test.
Bondar, I. V., D. H. Han, and H. K. Cho. "Synthesis of Nanocomposite Adsorbent on the Base of Polypropylene Fabric with Copper Ferrocyanide Grains." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35459.
Full textEzat, Gulstan S. "The influence of multi-walled carbon nanotubes on the properties of polypropylene nanocomposite : the enhancement of dispersion and alignment of multiwalled carbon nanotube in polypropylene nanocomposite and its effect on the mechanical, thermal, rheological and electrical properties." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5703.
Full textDulgerbaki, Cigdem. "Synthesis And Characterization Of Polythiophene/montmorillonite And Polythiophene/polypropylene Composites." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607762/index.pdf.
Full textelectrical conductivities were measured by four probe technique. Since PTP/MMT composites are unprocessable PTP/polypropylene(PP) composites were prepared. Amounts of PTP were changed in the range 2-30 % by weight in the composites. Mechanical properties were investigated by tensile tests. Four probe technique was used for measurement of electrical conductivities. Morphological characterizations were made by SEM. Formation of PTP and its incorporation in PTP/MMT composite were confirmed by FTIR analysis. DSC results showed that PTP does not have any thermal transition in the range 25-300 0C. TGA results showed that PTP/MMT composites have outstanding stability compared to that of PTP. XRD analysis revealed the formation of nanocomposites resulting from intercalation of thiophene in MMT at high MMT contents. Composites were observed as globular particles and clusters in SEM studies. Conductivity values of PTP/MMT composites were in the order of 10-3 S/cm. It is observed that tensile modulus of PTP/PP composites increases by the addition of PTP, but percentage strain at break does not appreciably change. Increasing PTP content increased electrical conductivity.
Oliveira, Junior Adair Rangel de. "Obtenção de nanocompositos poliprolipeno-argila compatibilizados com organossilano." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248736.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: Este trabalho teve como foco principal a obtenção de argilas expandidas por meio da modificação de argila natural com organossilanos, e depois sua incorporação em uma resina de polipropileno em extrusora de rosca dupla para a obtenção de nanocompósitos. As argilas usadas neste estudo foram as argilas montmoriloníticas sódicas Polenita e GelMax, bem como a argila organofílica Viscogel. Os organossilanos empregados no tratamento químico das argilas naturais foram o aminopropiltrimetoxissilano, glicidoxipropiltrietoxissilano e o metacriloxipropiltrietoxissilano. A obtenção da argila expandida foi fortemente influenciada pelas condições reacionais, como tipo e concentração do silano, solvente e pH do meio. As análises de difração de raios X revelaram que os melhores resultados de expansão da argila foram alcançados ao usar o silano aminopropiltrimetoxissilano em meio aquoso na faixa de pH entre 8 e 10. Segundo os dados de análise térmica, esta argila apresentou uma estabilidada térmica bem superior às tradicionais argilas organofílicas. Antes da incorporação da argila à matriz de polipropileno, primeiramente fez-se um estudo de otimização das condições de mistura, usando-se para isto a argila organofílica Viscogel, de elevado espaçamento basal. Desenvolveu-se um perfil de rosca com alta taxa de cisalhamento, no qual foi obtido um nanocompósito com dispersão de tamanho das lamelas da argila entre 5 a 15 nm. Tal dispersão resultou em ganho nas propriedades mecânicas em torno de 30 % em relação ao polipropileno puro. Este perfil de rosca foi, portanto, utilizado para realizar o processamento do polipropileno com a nova argila expandida. A partir dos resultados de difração de raios X e de microscopia eletrônica de transmissão, concluiu-se que não foi possível delaminar totalmente esta argila no polímero, como observado para a argila organofílica. Porém, os resultados relativos às propriedades mecânicas dos materiais obtidos mostraram que a argila modificada com aminopropiltrimetoxis-silano apresentou propriedades semelhantes às da argila organofílica, indicando que apesar do menor grau de dispersão, estas propriedades foram favorecidas pela maior interação entre a argila modificada e a matriz polimérica
Abstract: The purpose of this work was to obtain expanded clay by modifying clay with organosilane, and its incorporation into polypropylene resin to prepare a polypro-pylene-clay nanocomposite. Natural sodium montmorillonite (GelMax, Polenita) as well as organophylic clay (Viscogel ED) were used for this purpose. Three types of silanes were used to modify the clay: Aminopropyltrimethoxysilane (APS), glyci-doxypropyltriethoxysilane (GPS) and methacryloxypropyltrimethoxysilane (MPS). The expanded clay was strongly affected by reaction conditions, such as silane type and concentration, solvent and pH. According to XRD analysis, the higher basal distance was achieved in aqueous dispersion (pH 8-10) using the APS as a modifier. Modified clay showed superior thermal stability in comparison to organo-phylic clay, using thermogravimetric analysis. Besides the clay modification pro-cess, the screw profile influence on nanocomposite properties was also evaluated. An organophylic clay (Viscogel) was used to optimize the extrusion conditions, in this study. The composite processing was carried out in a twin screw extruder with higher shear screw profile. In this way, an exfoliated nanocomposite was obtained, where the clay layer thickness was between 5 and 15 nm. The flexural modulus of such nanocomposite was 30% higher than virgin polypropylene. This higher shear screw profile was used to extrude the polypropylene/aminopropylsilane-modified clay. Based on the X-ray diffraction and transmission electron microscopy results, a satisfactory exfoliation degree for silane-modified clay was not achieved, as observed for organophylic clay. In spite of the low exfoliation level of silane-modi-fied clay, the mechanical properties of its composite were similar to the organo-phylic clay based nanocomposite. This fact was attributed to better adhesion between polypropylene-silane modified clay than the polypropylene-organophylic clay system
Doutorado
Físico-Química
Doutor em Ciências
Fermino, Danilo Marin. "Propriedades mecânicas e térmicas de nanocompósito híbrido de polipropileno com adição de argila e celulose proveniente de papel descartado." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-20062016-083922/.
Full textThis work concerns to the study of the mechanical and thermal behavior of the hybrid polypropylene nanocomposite with a Brazilian bentonite clay from State of Paraíba (PB), known as \"Chocolate\" in concentrations of 1, 2 and 5 % by weight with addition of 1 and 2 % in weight cellulose discarded bond paper. The compatibilizer agent based on maleic anhydride grafted polypropylene, known as PP-g-MA, was added at 3 % weight concentration through the melt intercalation technique using a twin-screw extruder, and afterwards, the specimens were prepared by injection process. The mechanical behavior was evaluated by strength, flexural strength and impact tests. The thermal behavior was evaluated by the differential scanning calorimetry (DSC) and thermogravimetry (TGA). The morphology of the nanocomposites was studied by the technique of scanning electron microscopy (SEM). The clay, cellulose and the hybrid nanocomposites were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF) and infrared spectroscopy (FTIR). Results of mechanical tests showed an 11 % and 14 % increase in the tensile strength and Young\'s modulus, respectively, for the nanocomposite PPA 5 % with clay. The nanocomposite PPA 2 % with clay obtained a 63 % increase in strength Izod impact test. The hybrid nanocomposite PPAC 1 % obtained an 8 % increase in tensile strength. In the Izod impact test, the hybrid nanocomposite PPAC 2 % obtained 14 % increased in the impact strength.
Letoffé, Adrien. "Élaboration et caractérisation d’une matrice polypropylène chimiquement modifiée et chargée GNP/graphène fonctionnalisés." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0076.
Full textIn the last decade, the environmental awareness of the need to reduce human impact on the environment affects the research sector. Reducing the fuel consumption and the human gas emissions became a priority, the humanity needs to switch to more eco-efficient patterns of consumption. In the transport field, numerous new lines of research are possible, like lighter structure. Composite materials, like multi-layered steel/polymer, appeared to be the perfect candidates to reach that objective. The polymer part of such material needs to present good shock absorption and thermo-electrical properties, and good compatibility with a metallic surface. The objective of this thesis is the elaboration and characterization of a polymer material with such properties that can be produced at industrial scale. To obtain good compatibility with the metal surfaces, the isotactic polypropylene-grafted-Maleic anhydride was selected as the initial material. This matrix presents good chemical property, its major drawback is its brittleness. A crosslinking reaction based on the reaction between MAH and amine groups was used to modify the mechanical properties of the matrix. The PP-g-MAH were crosslinked by twin-screw reactive extrusion with different configurations. The reaction affects the microstructure and the mechanical behavior of the materials, with a switch from brittle to ductile. The switch is explained by the variation of micro-mechanism of deformation implied by the crosslinked network. The solution used to modify the thermo-electrical properties of the material is the dispersion of different carbon nano-fillers such as graphite. To raise the dispersion quality of the fillers, and the compatibility between the carbon filler and the polymer matrix, a new method of functionalization of the graphite, by plasma discharge was developed. This new method implied a diminution of the filler thickness and an oxidation of the graphene surface, without any significative degradation of the fillers quality. Two types of nanocomposites were produced, one with an unmodified graphite filler and another one with a graphite modified by plasma treatment. Even with high filler concentration no electrical percolation was obtained, a high fillers exfoliation process need to be obtained. The functionalization of the graphite implied a carbon dispersion improvement, thus a better compatibility between the filler and the matrix
Işık, Kıvanç Tanoğlu Metin. "Layered silicate/polypropylene nanocomposites/." [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezler/master/makinamuh/T000532.pdf.
Full textOliveira, Jener de. "Estudo de aditivação em massa ou por recobrimento de filme de BOPP em compostos orgânicos e nanopartículas anti UV." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266668.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Filmes poliméricos são amplamente utilizados no setor alimentício e médico hospitalar e as principais aplicações são como embalagens, substratos para fitas e curativos. A escolha do melhor material está intrinsecamente ligada às suas propriedades e também ao custo de cada polímero. Por isso é extremamente relevante a preocupação com o processo de degradação, que influencia diretamente as propriedades dos polímeros e é o resultado do ataque físico e/ou químico proporcionado pelo ambiente (temperatura, umidade, radiações ionizantes), tempo de exposição e condições de processamento e de serviço. Neste trabalho buscou-se analisar a prevenção destes processos degradativos em filmes de polipropileno bi-orientado - BOPP, polímero comercialmente atraente pela sua versatilidade, por meio do uso de aditivos antioxidantes e de absorvedores de radiação UV comerciais, estes últimos na forma de compostos orgânicos e de nanopartículas inorgânicas, aplicados no filme em massa ou em recobrimentos especialmente formulados para este fim. O uso do recobrimento teria ainda como vantagem adicional, a possibilidade de aplicação durante o processo de impressão, protegendo não só o filme como também as cores da impressão, permitindo, além disso, a partir de um filme commodity e formulações de recobrimento feitas sob medida para cada cliente, inclusive de pequeno porte, a obtenção de filmes especiais a um menor custo. Amostras de filmes preparados foram envelhecidas artificialmente e naturalmente e suas propriedades foram monitoradas em ensaios de resistência à tração (tensão na ruptura e alongamento), medida do índice de carbonila por espectroscopia de infravermelho, medida da absorção de radiação ultravioleta por meio de espectrofotometria de UV/visível e análise térmica (temperatura de transição vítrea e de fusão). O trabalho gerou resultados promissores, conclusão obtida pela análise dos ensaios mecânicos, sendo que a tensão de ruptura de um dos filmes aditivados no recobrimento, submetido ao intemperismo por 24 semanas, foi de 1,5 kg/cm versus 1 kg/cm no filme virgem (sem aditivos) submetido a 11 semanas. Houve redução na taxa de degradação medida nos ensaios de absorção de infravermelho, sendo o índice de carbonila mantido a patamares de 0,01 para filmes aditivados versus 0,7 para filmes não aditivados, quando sujeitos a degradação acelerada em equipamento QUV. Houve aumento da absorção de radiação ultravioleta em até 75% comparativamente ao filme virgem, resultado obtido pela adição de absorvedores orgânicos ou também de nanopartículas de óxido metálico
Abstract: Polymeric films are very used on products for food and hospital markets, mainly for packaging, adhesive tapes backing and dressings. The material's choose for both markets are done based on polymer properties and cost. Due this reason, it is too relevant to worry with degradation of material that influences the polymer properties. The degradation process comes from chemical and physical attack. An example is the environmental conditions, like temperature, humidity, radiation, exposure time and process/service conditions. This work looked for to evaluate and to prevent this degradation process that occur on bi-oriented polypropylene films (BOPP) through the use of different additives, like antioxidants and UV absorbers, organic compounds/inorganic nanopartículas, that can be applied on the film by different process, like inside its matrix or through varnish coatings. Samples of said films was aged on different conditions, natural or accelerated aged, and its properties was evaluated through different techniques, like tension/elongation, carbonyl index, FTIR, UV-Vis absorbance and thermo analysis (TGA, DSC). Through these techniques, it was evaluated the achieved protection grade of the film when treated by: UV absorber and Antioxidant applied by coating varnish UV absorber and antioxidant applied inside its matrix Nanoparticle of ZnO applied inside its matrix. The coating with varnishes can be easily made by a printing process. This process to protect the film was chosen in the work in order to study its influence to protect not only the film, but also the inks printed over it, allowing the use of a commodity film. This way, it is possible to get a tailor-made film, in order to achieve desired properties with a low cost process. It was possible to achieve promising results. This conclusion was made based on the tests results, like: the tensile strength analysis of films subjected to weather aging for 24 weeks shown results of 1.5 kg/cm against 1 kg/cm of virgin film aged during 11weeks; FTIR shown a reduction on the polymer degradation rate measured by infrared absorption; the carbonyl index of films with additives, when submitted to QUV or weather aging, maintained at levels of 0.01 versus 0.7 of virgin polymers; it was possible to achieve 75% of UV absorption if compared to virgin film. All the different additives and process conditions presented some advantage if compared with virgin polymer, as presented by this work
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química
Njoroge, Daniel [Verfasser]. "Thesis: Preparation and characterization of modified-graphene oxide/polypropylene nanocomposites : polypropylene nanocomposites / Daniel Njoroge." Berlin : epubli, 2016. http://www.epubli.de/.
Full textThiraphattaraphun, Linda. "Structure/property relationships in polypropylene nanocomposites." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/structureproperty-relationships-in-polypropylene-nanocomposites(388eafc0-a98e-4a78-be0d-4d647a122d87).html.
Full textYayla, Saniye. "Production And Characterization Of Polypropylene/organoclay Nanocomposites." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12608485/index.pdf.
Full text30B, Cloisite®
15A, and Cloisite®
25A were used as organoclay. iv In order to determine the optimum amount of compatibilizer, PP/compatibilizer blends were produced with different compositions. The content of compatibilizer was determined as 5 wt % based on the mechanical tests. Then, ternary nanocomposites were prepared with 5 wt % compatibilizer and 2 wt % organoclay contents. In addition, neat PP and PP/organoclay composites were prepared in order to make comparison. After that, the samples were characterized. According to the XRD analysis, the highest increase in the interlayer spacings of organoclays were observed in the PP/E-MA-GMA/Cloisite®
15A (23%) and PP/E-MA-GMA/ Cloisite®
25A (88.3%) ternary systems. SEM micrograms revealed that compatibilizer E-MA-GMA is the most compatible elastomer with PP. Thus, it was decided to investigate the effect of mixing order on the properties of these nanocomposites with E-MA-GMA. DSC analysis showed that the melting behavior of the nanocomposites does not change significantly with the presence of organoclay and compatibilizer. In addition, compatibilizers and organoclays have no significant nucleation activity in PP. The systems PP/E-MA-GMA/Cloisite®
15A and PP/E-MA-GMA/Cloisite®
25A have the highest improvements according to the results of mechanical tests. The results of mechanical tests showed that the mixing sequence (PEC), in which PP, organoclay and compatibilizer were compounded simultaneously in the first extrusion run, is the best sequence.
Khoshkava, Vahid. "Polypropylene (PP) nanocomposites incorporating nanocrystalline cellulose (NCC)." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121442.
Full textLe principal objectif de cette dissertation consiste à évaluer la faisabilité de la préparation de polypropylène bien dispersé (PP) / la cellulose nanocristalline du (NCC) nanocomposites par traitement par fusion. Il ya un intérêt croissant à utiliser du (NCC) comme renforcement dans les systèmes de polymère à cause de ses propriétés intéressantes et les sources de cellulose abondante et renouvelable. La préparation de nanocomposites polymères incorporant du NCC a été principalement effectuée en utilisant une solution ou un mélange d'eau-assistée. Seulement quelques essais ont été faites à préparer en utilisant un mélange à l'état de fondre. Le polypropylène (PP) est un polymère produit à de larges applications dans l'industrie de l'automobile, produits pharmaceutiques et les industries d'emballage.Dans la première phase de ce projet, les propriétés physiques (forme, taille et d'énergie de surface) du NCC sont évaluées. Une équation a été présentée pour estimer l'énergie de la dispersion du NCC dans les matrices à base de polymère dans une la pièce et les données d'énergie de surface à haute température. L'influence de la modification de surface du NCC et son interaction avec un polymère polaire (acide polylactique (PLA)) et un polymère non polaire (PP) a été évaluée.Dans la deuxième phase de ce projet, la relation entre la structure d'agglomérat du NCC et sa dispersion dans des matrices de polymère est considérée. L'effet des diverses techniques de séchage sur la structure des agglomérats du NCC est examiné. On a constaté que séchage par pulvérisation et par lyophilisation du NCC, les suspensions aqueuses se traduisent dans les agrégats du NCC denses et compactes. D'autre part, la pulvérisation par lyophilisation des suspensions aqueuses du NCC pourrait former des agglomérats ou des structures poreuses plus ouvertes. La structure des agglomérats dépend de la concentration initiale de la suspension aqueuse du NCC avant la pulvérisation par lyophilisation. Dans le régime à faible concentration (en dessous de2%environ en poids), une structure en forme de bande de fibres interconnectée à l'échelle nanométrique est formée. D'autre part, le micron dimensionné des particules de structure sphérique est formé à une concentration plus élevée (ca. 2 wt.% et au-dessus). La surface spécifique de la poudre du NCC produite en utilisant le séchage par atomisation ou lyophilisation a progressé de plus de 30 fois. Les nanocomposites contenant du polypropylène séché par pulvérisation du NCC, et lyophilisés à froid du NCC (NCCSFD) ont été préparé dans un malaxeur discontinu interne. La microscopie en lumière polarisée (PLM) et la microscopie électronique à balayage (SEM) ont montré une meilleure dispersion des particules de NCCSFD. Les résultats de l'analyse mécanique dynamique (DMA) des tests de traction ont démontré une amélioration considérable de modules de résistance à la traction des échantillons contenant des particules de NCCSFD. Des mesures rhéologiques, y compris les tests de viscoélasticité linéaire et non linéaire, ont été effectuées sur des prélèvements des PP/NCC. De petits tests oscillatoires d'amplitude (SAOS) ont montré un impact considérable d'incorporation de NCCSFD sur les caractéristiques rhéologiques des échantillons de PP. Des résultats réguliers de cisaille ont révélé une forte fluidification par cisaillement et une limite d'élasticité pour les échantillons de PP contenant des particules de NCCSFD. La magnitude de la limite de stress et le degré de rhéofluidification a augmenté avec la concentration de NCCSFD. Les effets de la structure du NCC (sous forme de bande et la structure en mousse sphérique) sur les propriétés rhéologiques ont été examinés.
Lin, Yong. "Toughening mechanism of polypropylene/calcium carbonate nanocomposites /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CBME%202009%20LIN.
Full textLi, Zhi. "Three-Dimensional Optical Characterization of Heterogeneous Polymer Systems." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5008.
Full textChan, Hong Yu. "Crystallization of polypropylene/vermiculite and polyethylene/vermiculite nanocomposites." access abstract and table of contents access full-text, 2004. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21173990a.pdf.
Full textAt head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Aug. 31, 2006) Includes bibliographical references.
Streller, Rouven Cornelius. "Boehmite als Nanofüllstoffe für Polypropylen-Nanocomposites und Nanopartikel-modifizierte Polypropylen/Kautschuk-Blends." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:25-opus-61139.
Full textHernandez-Luna, Alejandro. "Structure property and deformation analysis of polypropylene montmorillonite nanocomposites." Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4213/.
Full textKalaitzidou, Kyriaki. "Exfoliated graphite nanoplatelets as reinforcement for multifunctional polypropylene nanocomposites." Diss., Connect to online resource - MSU authorized users, 2006.
Find full textTitle from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references. Also issued in print.
Lertwimolnun, Wiboon. "Réalisation de nanocomposites polypropylène / argile par extrusion bivis." Phd thesis, École Nationale Supérieure des Mines de Paris, 2006. http://pastel.archives-ouvertes.fr/pastel-00001873.
Full textBoubekri, Khalid. "Propriétés mécaniques des nanocomposites à base de polypropylène." Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/23664/23664.pdf.
Full textWong, Kwok Wai. "Preparation and crystallization characterization of polypropylene-layered silicate clay nanocomposites." access abstract and table of contents access full-text, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21175184a.pdf.
Full textAt head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.
Soltan, Omar. "Polypropylene/filler nanocomposites by melt compounding and in situ polymerization." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5310.
Full textENGLISH ABSTRACT: The properties of polymer nanocomposites depend greatly on the chemistry of the polymer matrices, the nature of the nanofillers, and the way in which they are prepared. Understanding the synthesis–structure–property relationship of nanocomposites is vital for the development of advanced polymer nanocomposites with enhanced mechanical strength, stiffness and toughness for structural engineering applications. To this end, the primary aim of this study was to determine the impact that the preparation methods have on the properties of PP/filler nanocomposites, with specific focus on the in situ polymerization of propylene via the methylaluminoxane (MAO) activated metallocene catalyst technique. Two different fillers (Silica and Calcium carbonate) were used as support for the metallocene catalysts. Different supporting methodologies for the synthesis of the supported catalyst were examined. A C2 symmetric metallocene catalyst ansa dimethylsilylbis(2-methyl benzoindenyl) zirconium dichloride (MBI) was used in this study. The catalyst systems were then evaluated for propylene polymerization. The early observation shows that a direct adsorption of the metallocene onto the filler has a diminishing effect on the catalyst productivity and the fillers had to be treated with MAO in order to avoid catalyst deactivation by the filler surface. Due to the low productivity of the supported active species, the presence of soluble catalyst active species, besides the supported active species is required in the synthesis of PP nanocomposites via in situ polymerizations. The syntheses of PP nanocomposites were carried out via in situ polymerization in which different quantities of MAO treated fillers were reacted with pre-activated catalyst solution. The effect of the addition of MAO-filler on the polymerization kinetics and consequently on PP matrix microstructure was investigated. Changes in the in situ polymerization kinetics, compared to kinetics of homogeneous polymerization, were observed. Therefore, the microstructure of the polymer matrix was also influenced by the presence of nanofillers in the polymerization media. The influence of the different synthesis methods on the performance of the nanocomposites was investigated using melt-mixed PP/filler nanocomposites obtained using PP homopolymer. The dispersed phase morphologies of the different nanocomposites were investigated by transmission electron microscopy (TEM). Results show that PP nanocomposites with improved filler dispersion were achieved by in situ polymerization compared to melt-mixed nanocomposites. The influence of the synthesis method on the crystallization behaviour of PP nanocomposites was also investigated. It was found that, for the in situ prepared nanocomposites the tacticity of the PP matrix plays the major role in determining the degree of crystallinity. Results also show that when nanocomposites with comparable PP matrices are compared, the overall crystallization rate of the in situ polymerized nanocomposites is higher than that of the melt mixed nanocomposites. The mechanical properties of in situ polymerized PP and melt mixed PP nanocomposite were also investigated and compared. Due to improved nanoparticle dispersion in the PP matrix, in situ polymerized nanocomposites show enhanced mechanical properties, especially tensile and impact properties, compared to pure PP and melt mixed prepared nanocomposites when a PP matrix of equivalent microstructure was used. Finally, the melt compounding method was further investigated using different fillers and commercial PP as a matrix. The effect of filler type, size and applied surface coating on the flow and mechanical properties of PP nanocomposites was studied. The aim of this part of this study is to obtain a good trade-off between the processability and the mechanical properties and to gain insight into the cause of the emergence of different properties for nanocomposites prepared by melt compounding.
AFRIKAANSE OPSOMMING: Die eienskappe van polimeer nanokomposiete hang grotendeels af van die chemie van die polimeer matriks, die wese van die nano-vullers, en die manier waarop hierdie materiale berei word. Om die sintese-struktuureienskap verwantskap te verstaan is noodsaaklik vir die ontwikkeling van gevorderde nanokomposiete met beter meganiese eienskappe, styfheid en taaiheid vir strukturele ingenieurstoepassings Die primêre doelstelling van hierdie studie was dus om die impak van voorbereidingsmetodes op die eienskappe van PP/vuller nanokomposiete te bestudeer, met spesifieke fokus op die in-situ polimerisasie van propileen met metiel alumoksaan-geativeerde metalloseen kataliste. Twee verskillende vullers (silika en kalsium karbonaat) is gebruik as ondersteuning vir die metalloseen kataliste. Verskillende metodiek is gebruik om die ondersteunde kataliste te berei. ‘n C2 simmetriese metalloseen katalis ansa-dimetielsiliel(2-metiel bensoindeniel) sirkonium dichloride (MBI) is in die studie gebruik. Die katalissisteme is daarna evalueer vir propileen polimerisasie. Daar is oorspronklik vasgestel dat direkte adsorpsie van die metalloseen op die vuller ‘n negatiewe effek op die katalis aktiwiteit gehad het, en dat die vuller oppervlak eers met MAO behandel moes word om deaktivering van die katalis deur die vuller-oppervlak te vermy. As gevolg van die lae aktiwiteit van die ondersteunde aktiwe katalisspesies, is die teenwoordigheid van opgeloste aktiewe katalis nodig vir die voorbereiding van PP nanokomposiete via in situ polimerisasie-reaksies. Die sintese van PP nanokomposiete is uitgevoer deur in –situ polimersiasie waartydens verskillende hoeveelhede MAO-behandelde vullers gereageer is met vooraf-geaktiveerde katalis oplossings. Die effek van die byvoeging van MAO-vuller op die polimerisasie-kinetika en gevolglik op die PP matriks mikrostruktuur is ondersoek. Dit is gevind dat die mikrostruktuur van die polimeer-matriks beinvloed word deur die teenwoordigheid van nanovullers in die polimerisasie-medium. Die invloed van verskillende bereidingsmetodes op die eienskappe van die nanokomposiete is ondersoek deur smelt-vermengde PP/vuller nanokomposiete te maak. Die dispersie-fase morfologie van verskillende nanokomposiete is ondersoek deur transmissie elektron mikroskopie (TEM). Resultate wys dat PP nanokomposiete met verbeterde vuller-dispersie berkry is deur in situ polimerisasie in vergelyking met die smelt-vermengde materiale. Die effek van die sintese-metode op die kristallisasie van die PP nanokomposiete is ook ondersoek. Daar is gevind dat, vir die in situ bereide nanokomposiete, die taktisiteit van die PP matriks die grootste rol speel in die bepaling van die persentasie kristalliniteit. Resultate het ook gewys dat, wanneer nanokomposiete met soortgelyke PP matrikse vergelyk word met die in situ nanokomposiete, die laasgenoemde se tempo van kristallisasie hoer is as vir die smelt-vermengde nanokomposiete. Die meganiese eienskappe van die in situ bereide en smelt-vermengde PP nanokomposiete is ook ondersoek en vergelyk. As gevolg van verbeterde nano-partikel dispersie in die PP matriks, het die in situ bereide nanokomposiete beter meganiese eienskappe openbaar, in vergelyking met die smelt-vermenge nanokomposiete, veral trek- en slagsterkte. . Laastens is die smelt-vermengings metode verder ondersoek deur gebruik te maak van verskillende vullers en kommersiële PP as matriks. Die effek van die tipe vuller, die grootte en die oppervlakbedekking van die vullerpartikels op die vloei en meganiese eienskappe van die PP nanokomposiete is ondersoek. Die doel van hierdie studie was om ‘n balans te kry tussen prosesseerbaarheid en meganiese eienskappe en om insig te verkry oor die verskille in eienskappe wat openbaar word wanneer smeltvermengde nanokomposiete bereie word.
Touchaleaume, François. "Elaboration de nanocomposites à matrice polypropylène chargée d'argile native." Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL10177.
Full textThis work focuses on polypropylene (PP)/clay nanocomposites based on pristine montmorillonite (NaMMT). The elaboration strategy involves the use of a polar polymer based masterbatch to disperse NaMMT in the PP matrix. Water assisted extrusion is used to finely disperse the native montmorillonite in the polar host polymer.In the first part, the dispersion of modified and pristine montmorillonite in polyamide 6 (PA6) using water assisted extrusion is presented. The morphological analysis of the PA6 nanocomposites and its outcome on the thermomechanical properties were studied. PA6 masterbatches were then elaborated using water assisted extrusion and dispersed in PP to obtain nanocomposites blends. Their morphologies are detailed, in relation with the processing conditions, and the related mechanical properties.In the second part, polyether-block-amide (PEBA) was used as host polymer to disperse modified and native montmorillonite. Their dispersion is obtained thanks to the water assisted extrusion process. The morphological analysis and its influence onto the thermomechanical properties and on the deformation mechanisms were studied. PEBA masterbatch were then prepared using water assisted extrusion and dispersed into PP to obtain nanocomposites blends. The study of their morphologies is presented, related to the extrusion conditions, and the corresponding macroscopic performances.Finally, the comparison of the results obtained in the case of PA6 and PEBA nanocomposites blends is discussed to evidence the influence of components rheology and polarity as well as the processing conditions onto the macroscopic behaviors of the materials
Can, Semra. "Characterization Of Serpentine Filled Polypropylene." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609434/index.pdf.
Full texter March 2008, 158 pages In this study, the aim is to prepare polypropylene (PP)/serpentine composites and study their mechanical, thermal and morphological properties. Another objective is to explore whether it is possible to have PP/serpentine nanocomposites with melt intercalation method by using the advantage of the layer silicate structure of serpentine. The most widely used fillers in PP are talc and mica which belong to the phyllosilicates group of silicate minerals. So far, there has been almost no study employing serpentine as filler in either any polymers or PP, although it also belongs to the same group of minerals as talc and mica. Accordingly, it was planned to divide the work into the study of two groups. In group 1, for the compositions with 2, 5, 10 and 20 wt% serpentine, the particulate filler effects of serpentine both alone and in the presence of surface treatments with hydrochloric acid (HCl) and silane coupling agent (SCA) were investigated. The most impressive results in terms of static and dynamic mechanical properties were achieved with SCA rather than HCl. When the effect of serpentine without any treatment is considered, reinforcing effect of it can easily be observed without deteriorating the composite properties even at high filler loadings. In group 2, the nanofiller effects of serpentine in 2 and 5 wt% filled compositions by modification of both the filler and the matrix were aimed to be examined with melt intercalation method. In addition to HCl and SCA treatments, maleic anhydride grafted polypropylene (PP-g-MA) and quaternary ammonium salt (QAS) of cetyl-trimethyl-ammonium bromide were used as compatibilizer and intercalating agent, respectively. While the amount of QAS was kept constant, different percentages of compatibilizer were employed. The presence of QAS and PP-g-MA further improved the properties with respect to group 1 members. Interestingly, the percentage strain at break values did not decrease as much as group 1 compositions with the same filler content. It can be concluded that partial intercalation of group 2 compositions was achieved, according to the X-ray and TEM results. Keywords: Serpentine, PP/serpentine composites, SCA, PP-g-MA, serpentine nanocomposites
Nguyen, Quang Tran. "Process for Improving the Exfoliation and Dispersion of Nanoclay Particles into Polymer Matrices Using Supercritical Carbon Dioxide." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27596.
Full textPh. D.
Lee, Byoung-Jo. "Nucleating agent-assisted preparation of polyprolylene (PP)/polyhedral oligomeric silsesquioxane (POSS) nanocomposites and their characterization." Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1247779040.
Full text"August, 2009." Title from electronic dissertation title page (viewed 9/23/2009) Advisor, Sadhan C. Jana; Committee members, Avraam I. Isayev, James L. White, George G. Chase, Shing-Chung Josh Wong; Department Chair, Sadhan C. Jana; Dean of the College, Stephen Z. D. Cheng; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
Vamvounis, Emmanouil. "Polypropylene ternary nanocomposites with layered silicates and single-walled carbon nanotubes." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499936.
Full textNormand, Guillaume. "Nanocomposites à matrice polypropylène renforcée par argile lamellaire - Etude de la relation procédé-structure." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEM053/document.
Full textThis PhD focuses on the relationship between the preparation process and the structure of polypropylene/clay nanocomposites. First, the samples were prepared via an internal mixer. Scanning electron microscopy observations, completed by X-ray diffraction analysis and rheology measurements enabled us to characterize the clay dispersion state in the nanocomposite at different scales. Three organoclays were compared. It was shown that the chemical compatibility between the clay and the matrix was essential to ensure a good dispersion: Cloisite 20 and Dellite 67G showed good dispersion states at all scales, whereas Cloisite 30B did not. The influence of rotor speed and mixing time on the clay dispersion state was shown. The percolation threshold of the clay was determined. The link between dispersion state and crystallinity was also studied.The samples were then prepared via a twin-screw extruder. The influence of screw speed on the clay dispersion state was demonstrated, as well as the matrix degradation at high screw speed. The evolution of the dispersion state along the screw profile showed that intercalation was reached early in the screw profile, whereas exfoliation evolved linearly until the last mixing elements. A lower barrel temperature, as well as a more viscous matrix did not improve the clay dispersion state, and did not prevent the matrix degradation. Finally, the Ludovic© software allowed us to apprehend the thermomechanical phenomena involved during extrusion, but also to optimize the process
Al-Shehri, Abdulhadi S. "Tensile and fracture behaviour of isotropic and die-drawn polypropylene-clay nanocomposites : compounding, processing, characterization and mechanical properties of isotropic and die-drawn polypropylene/clay/polypropylene maleic anhydride composites." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5223.
Full textShepherd, Céline. "New routes for functionalised nanoparticles for polymer nanocomposites." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:b148b604-80c9-464f-937c-0b3f1553468a.
Full textDomenech, Trystan. "Structure et propriétés de nanocomposites polypropylène/argile lamellaire préparés par mélange à l'état fondu." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00684786.
Full textErdmann, Michael. "Entwicklung innovativer Compatibilizer-Systeme für Polypropylen-Nanocomposites auf der Basis organophiler Schichtsilikate." Berlin Logos-Verl, 2009. http://d-nb.info/997726830/04.
Full textChu, Chun. "Development of polymer nanocomposites for automotive applications." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37128.
Full textZhang, Yan. "Relationship between morphology, crystallization behavior and mechanical properties of polypropylene micro- and nanocomposites /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CENG%202004%20ZHANG.
Full textShen, Yucai. "Processing and properties of melt processed polypropylene-clay and polylethylene terephthalate-clay nanocomposites." Thesis, Queen's University Belfast, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546426.
Full textANDRADE, Daniela de Lourdes Anjos Coutinho Simões. "Influência das variáveis de processo na formação e propriedades de nanocompósitos polipropileno/bentonita." Universidade Federal de Campina Grande, 2009. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1691.
Full textMade available in DSpace on 2018-09-12T12:56:27Z (GMT). No. of bitstreams: 1 DANIELA DE LOURDES ANJOS COUTINHO SIMÕES ANDRADE - TESE (PPGEP) 2009.pdf: 2248344 bytes, checksum: 28a93ae4236853f59fe35037c2ab6f28 (MD5) Previous issue date: 2009
A proposta deste trabalho foi preparar nanocompósitos de polipropileno/compatibilizante/bentonita, pelo método de intercalação na fusão, utilizando como carga uma argila sódica comercial Argel, fornecida por uma indústria local, purificada e modificada organicamente com um sal quaternário de amônio empregando diferentes métodos de preparação. Ao longo do trabalho foram utilizadas duas matrizes e dois tipos de compatibilizantes: PP H103, PP H401, Polipropileno modificado com anidrido maleico (PP-g-MA) e Copolímero de etileno e álcool vinílico (EVOH), respectivamente. As argilas foram caracterizadas por difração de raios-X (DRX), espectroscopia de infravermelho (FTIR) e análise termogravimétrica (TG) visando determinar o método de preparação mais eficiente para obtenção das argilas organofílicas. Uma vez determinado o melhor procedimento para organofilização, na segunda parte deste estudo, avaliou-se o efeito do tipo e teor de argila organofílica, bem como o tipo e teor de compatibilizante nas propriedades de filmes de polipropileno. De acordo com os resultados preliminares deste estudo, há uma indicação de que os filmes de nanocompósitos PP/PP-g-MA/argila organofílica, contendo 1% de argila organofílica e 15% de polipropileno modificado com anidrido maléico (PP-g-MA) podem ser promissores para o mercado de embalagens e poderão em um futuro próximo serem usados como um novo produto por empresas nacionais.
The purpose of this work is to prepare nanocomposites of polypropylene/compatibilizer/bentonite, by melting intercalation, with a commercial sodium clay – Argel – as filler. This clay was organically purified and modified by different methods, with a quaternary ammonium salt. The clays were characterized by X-Ray diffraction (XRD), infrared spectroscopy (FTIR) and thermogravimetric analyses (TG) to determine the most efficient preparation method. Before that, in the second stage of this study, the influence of the type and contend of organoclay in the properties of the polypropylene films was measured; the same was done for the compatibilizer. The preliminary results indicate that the nanocomposites film with 1% of organoclay and 15% of polypropylene grafted with maleic anhydride show promise as packing materials and may be used, in the near future, as a new product by the national industry.
Minisini, Benoit. "Modélisation et simulation moléculaire d'un matériau nanocomposite à base de polypropylène chargé de nanoparticules lamellaires." Le Mans, 2004. http://cyberdoc.univ-lemans.fr/theses/2004/2004LEMA1001.pdf.
Full textThis thesis lies in the scope of the fondamental and industriel research aiming Io better understand the physicochemical properties of nanocomposite polymer. Thanks Io an ab inito method we have shown a link between the reactivity of the montmorillonite surface and the oclahedral configuration. Then, the reactivity of différent surfactants used for the organo- modification of the montmorillonite is studied. Electrostatic properties of différent functional groups which could be grafted onto polyolefine are also studied. The influence of the surfactant on the organoclay properties is investigated with the classical molecular mechanic method. Classical molecular dynamies on graft polypropylene-surfactant-montmorillonite systems are performed to calculaie the interaction energies. Eventually, we study the role of binder of the surfactant
Minisini, Benoit Tsobnang François. "Modélisation et simulation moléculaire d'un matériau nanocomposite à base de polypropylène chargé de nanoparticules lamellaires." [S.l.] : [s.n.], 2004. http://cyberdoc.univ-lemans.fr/theses/2004/2004LEMA1001.pdf.
Full textKanbur, Yasin. "Conductive Polymer Nanocomposites Of Polypropylene And Organic Field Effect Transistors With Polyethylene Gate Dielectric." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613312/index.pdf.
Full texts and fullerenes were surface functionalized with HNO3 : H2SO4 before composite preparation. The CNT and fullerene content in the composites were varied as 0.5, 1.0, 2.0 and 3.0 % by weight. For the composites which contain surface modified CNT and fullerene four different compatibilizers were used. These were selected as TritonX-100, Poly(ethylene-block-polyethylene glycol), Maleic anhydride grafted Polypropylene and Cetramium Bromide. The effect of surface functionalization and different compatibilizer on mechanical, thermal and electrical properties were investigated. Best value of these properties were observed for the composites which were prepared with maleic anhydride grafted polypropylene and cetramium bromide. Another aim of this study is to built and characterize transistors which have polyethylene as dielectric layers. While doing this, polyethylene layer was deposited on gate electrode using vacuum evaporation system. Fullerene , Pentacene ve Indigo were used as semiconductor layer. Transistors work with low voltage and high on/off ratio were built with Aluminum oxide - PE and PE dielectrics.
Xiao, Dan. "Development and Investigation of High-Performance Fire Retardant Polypropylene Nanocomposites via High Energy Electrons." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-229650.
Full textChinellato, Anne Cristine. "Etude d'un procédé d'élaboration et caractérisation de nanocomposites à base de polypropylène et de montmorillonite." Vandoeuvre-les-Nancy, INPL, 2005. http://docnum.univ-lorraine.fr/public/INPL/2005_CHINELLATO_A_C.pdf.
Full textThis work dealt with polypropylene/organically modified montmorillonite (PP/o-MMT) nanocomposites. The main objective was to study the efficiency of using an acrylic acid modified PP (PP-g-AA) as a compatibilizer to promote the intercalation and/or exfoliation of the o-MMT in the PP, on the one hand; and the structures and properties of the resulting composites, on the other hand. Two kinds of PP-g-AA having the same acrylic acid content (6 wt. %) and differing in molar mass were used. The o-MMT content was 0, 1, or 5 wt. % and the PP-g-AA/o-MMT mass ratio was 0:1, 1:1, 2:1 or 5:1. X-ray diffraction and transmission electronic microscopy showed that without PP-g-AA, the structure of the PP/o-MMT was like that of a conventional micro-composite. With PP-g-AA, the o-MMT was intercalated. Compared to the neat PP, the PP/o-MMT showed an increase in thermal stability of up to 40°C and 30% in elastic modulus. However this increase was concomitant to a decrease in impact strength as the compatibilizer/montmorilonite mass ratio increased. Incorporation of the o-MMT in the PP always led to a decrease in CO2 permeability and the degree of decrease was more significant for compatibilized PP/o-MMT composites (better intercalation/exfoliation) reaching up to 50% with respect to the virgin PP. Based on the above results, it was concluded that the PP-g-AA was efficient to promote the intercalation/exfoliation of the o-MMT in the PP. However, there seemed no significant differences between the two PP-g-AA compatibilizers. Overall, for both PP-g-AA, better properties were obtained for higher PP-g-AA/o-MMT mass ratio
Chinellato, Anne Cristine Hu Guo Hua. "Etude d'un procédé d'élaboration et caractérisation de nanocomposites à base de polypropylène et de montmorillonite." Vandoeuvre-les-Nancy : INPL, 2005. http://www.scd.inpl-nancy.fr/theses/2005_CHINELLATO_A_C.pdf.
Full textOliveira, Camila Fernanda de Paula. "Melhoria da resistência no estado fundido do polipropileno através da adição de nanoargilas." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-20082010-162643/.
Full textIn this work nanocomposites of polypropylene (PP) were obtained. Three types of PP with melt flow rates of 1,5; 2,2 e 37,9 g/10min (230ºC/216kg) were used. The PP with the largest melt flow rate is a product modified with peroxide. These samples were mixed with PP masterbatch Nanocor nanoMax ®-PP. Masterbatch in different concentrations ranging from 3 to 12 wt%. The composites were obtained using a twin screw extruder and internal mixer. The masterbatch was characterized by X-ray fluorescence, X-ray diffraction (XRD) and infrared spectroscopy (FTIR). The composites were characterized by XRD, optical microscopy (OM) and transmission (TEM) and rheologically. The rheological characterization was made carrying out time sweep, small amplitude oscillatory shear (SAOS) tests in order to study the rheological behavior on the linear viscoelastic regime. Tests using a conical diewith which it is possible to measure elongational viscosity were also conducted. The shear viscosity at high shear rates was evaluated using a slit die The characterization results showed that the masterbatch is a mixture of polypropylene grafted with maleic anhydride and a smectite type clay, predominantly montmorillonite (MMT). The basal spacing of clay in the composites was greater than that of the clay within the masterbatch for every composites. It was shown to decrease with increasing concentration of masterbatch in the composite. The viscosity of composites increased during the time sweep experiments. This evolution of viscosity was attributed to changes of morphology of the composites. These variations were more important when the frequency used in the test was lower. The storage modulus obtained during COPA at low frequencies for composites was higher than the modulus of the pure polymers when the clay content was above 6%. This increase in modulus was greater for the lower melt flow index PP The rheological tests performed using the slit die showed that Cox-Merz rule was not valid for the composites. The elongational viscosity was shown to increase with increasing concentration of masterbatch.
Bar, Marcia. "Estudo da fotooxidação de nanocomposito PP/bentonita." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2008. http://tede2.uepg.br/jspui/handle/prefix/1387.
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The cation exchange of the bentonite and its processing are important factors to the polimeric nanocomposite formulation. The objective of this work was to produce nanocomposites of polypropylene / sodium bentonite and polypropylene / organophilic bentonite through melt intercalation and analyze the degradation produced by ultraviolet irradiation. Cetyl trimethyl ammonium bromide (C17H38BrN), Cetremide®, was used to organophilize the bentonite clay. Corotating twin screw extruder was used to process the nanocomposite; injection molded specimens were used for the flexural test and optical micrographs; hot pressed samples were used for DSC, XRD and FTIR. The XRD results showed that the samples of nature bentonite obtained better interaction with de polymer rather than treated clay, and produced intercalated nanocomposite. The degradation by ultraviolet irradiation was observed after 24 hours of exposition. All the samples showed the same photoproducts and at the same proportion until 240 hours of UV exposition; at higher times, 480 hours of UV exposition, the organophilize bentonite composite showed higher degradation than other ones. The flexural modulus decreased with degradation time. The degradation occurs due chromophores impurities presented in the samples, thus samples with clay show higher degradation, and organophilic clay contains ammonium salt that contribute to increase the degradation.
A troca de cátions da bentonita e o processamento são fatores muito importantes para a formação de nanocompósitos poliméricos. O objetivo deste trabalho foi produzir nanocompósitos de polipropileno / bentonita sódica e polipropileno / bentonita organofílica pelo método de intercalação no estado fundido e avaliar a degradação devido a exposição das amostras a irradiação ultravioleta. Foi usado o sal quaternário de amônio cetil trimetilamoneobrometo (C17H38BrN), Cetremide®,para obter a bentonita organofílica. No processamento foi usado uma extrusora de rosca dupla corrotacional; para o ensaio de flexão e de microscopia ótica foram usadas amostras injetadas; para o ensaio de DSC, DRX e FTIR foram usadas amostras prensadas a quente. Os resultados de raios-X mostraram que as amostras com bentonita natural tiveram uma melhor interação com o polímero do que a argila tratada, e formaram um nanocompósito intercalado. Os efeitos dos raios ultravioleta na degradação já são perceptíveis após 24 horas de exposição. Todas as amostras apresentam os mesmo foto-produtos e na mesma proporção até 240 horas de exposição UV; com tempos maiores, 480 horas de exposição, o compósito formado pela argila organofílica apresenta uma degradação mais acentuada que os outros materiais. O módulo de flexão diminuiu com o tempo de degradação; as trincas superficiais aumentaram com o tempo de degradação. A degradação ocorre devido as impurezas cromóforas presentes nas amostras, desta forma, amostras em cuja composição tem argila são mais degradadas, e no caso da argila organofílica ainda tem a presença do sal de amônio que também contribui para o aumento da degradação.