In this study, the effects of glycol type, organoclay type and concentration on the final properties of nanocomposites based on recycled poly(ethylene terephthalate) was investigated. For this purpose, first recycled PET was glycolysed and after that unsaturated polyester-montmorillonite nanocomposites were synthesized by using three different types of glycols (i.e. ethylene glycol (EG), propylene glycol (PG) and diethylene glycol (DEG)). As the first step, all the compositions were prepared by Cloisite 30B type of clay, and then for comparison of clay type, nanocomposites containing 1 wt. % of Cloisite 15A and Cloisite 25A type of clay were also synthesized. Morphological and mechanical analyses were performed for the characterization of the nanocomposites. According to the results of XRD analysis, for all glycol types maximum intercalation was observed in Cloisite 30B containing samples. Exfoliated structures were obtained in the samples containing EG at 1 wt. % Cloisite 30B content and DEG at 3 wt. % Cloisite 30B content. Mechanical tests showed that, for all properties, glycol type is the most effective experimental parameter. DEG based samples are the most flexible whereas PG based samples are the least flexible. EG and DEG based samples give maximum tensile strength and tensile modulus values at 1 wt. % clay loading. Samples prepared by DEG exhibited maxima in both flexural strength and modulus at 1 wt. % clay content. With respect to the organoclay type, Cloisite 30B containing samples gave the highest compatibility with the unsaturated polyester matrix as indicated by the tensile test results. Organoclay type and content had no positive effect on the impact strength. Clay particles acted as stress concentrators and lowered the impact strength.

Dans ce travail, nous montrons que les liquides ioniques (ILs) sont des milieux réactionnels efficaces pour des polycondensations difficiles ou impossibles à mener dans les milieux classiques. Des liquides ioniques acides de Brønsted (BAILs) ont été utilisés à la fois comme milieux réactionnels et comme catalyseurs pour la polyestérification de l'acide 12-hydroxy-dodecanoïque (12-HDA), pour celle d'oligoesters préformés à partir de mélanges diol/diacide équimolaires et pour celles de l'acide 2,2- bis(hydroxymethyl)propanoïque. Les polyestérifications dans les BAILs sont beaucoup plus rapides que les polyestérifications traditionnelles en masse. Des polyesters linéaires de Mw environ 40000 g/mol ont été obtenus après seulement 5-30 min de réaction à 110°C au lieu de plusieurs heures à 200 °C en masse. De la même manière, des polyesters hyperramifiés de Mw=10000 g/mol ont été obtenus après 1 h de réaction à 150°C dans les BAILs au lieu de plus de 8 h en masse. Des polyéthers linéaires de diols à longues chaînes aliphatiques, difficiles à synthétiser par les méthodes traditionnelles ont été obtenus très simplement par polyétherification directe dans des BAILs. Nous avons également mené des synthèses de polyamides difficiles ou impossibles à obtenir par polyamidification directe. Nous avons ainsi pu préparer des homopolyamides de la β-alanine, de la Lvaline et de la L-isoleucine et des copolyamides de l'acide 12-amino-dodécanoïque et d'acides α- et β- aminés naturels dans des ILs à anion phosphoré en présence de triphénylphosphite comme agent de condensation.

Ulm, Univ., Diss., 2008. Esterification.

Zugl.: Stuttgart, Univ., Diss., 2003. / Print-Ausg. bei Shaker, Aachen erschienen.

Ce travail porte sur le traitement de surface de pigments, d'oxyde d'aluminium, de fer et de titane par des polyesters acrylique et l'analyse des propriétés qui en résultent. Les mesures d'angle de mouillage montrent que le traitement rend les pigments plus hydrophobes. Ces traitements sont ils complets, avec un recouvrement homogène de la surface et quels sont les types de liaisons formées ? L'analyse quantitative a été menée par thermogravimétrie et spectroscopie infrarouge après traitement et lavages par différents solvants. Les résultats cohérents montrent que les molécules sont fixées sur les trois oxydes de fer, une partie des molécules seulement sur l'oxyde de titane, avec une plus faible fraction fixée sur l'alumine. Des liaisons chimiques sont détectées par spectroscopie infrarouge, assisté par un modèle de mécanique quantique. Cependant l'AFM et l'XPS montrent que le traitement de la surface n'est pas homogène, le polymère se dépose sous forme d'îlots. L'observation directe par AFM sur des plaquettes d'alumine est décisive. Elle montre que ce mode de dépôt résulte de la conformation des molécules en pelotes. Cette hétérogénéité est inhérente à la structure macromoléculaire, dont la contribution entropique empêche le dépôt planaire sur la surface. Nous préconisons l'utilisation de molécules plus petites ou une polymérisation in-situ.

[pt] Neste trabalho desenvolveu-se um material nacional constituido de misturas de resinas poliéster CRYSTIC rígida e flexível, para ser utilizado em Fotoplasticidade. Foi feito um estudo completo sobre o método de fundição e sobre o comportamento mecânico e ótico. Através de ensaios uniaxiais de tração e compressão, compressão diametral de discos e flexão pura de barras,estudou-se as influências da composição do material (teor de resina flexível na mistura) e de parâmetros de ensaio nos comportamentos mecânico e ótico, durante ciclos de carregamento e descarregamento e após descarregamento. A Técnica Fotoplástica Tridimensional, que analisa fatias de modelos descarregados, e que procura simular problemas de Conformação Mecânica de metais, foi aplicada à compressão plana de barras. Com o objetivo de se comparar resultados, realizou-se o mesmo ensaio em barras de alumínio e empregou-se, para o mesmo exemplo, um programa não linear de elementos finitos (NONSAP), baseado nos critérios de Von Mises, Tresca e Drucker-Prager. Esta comparação de resultados permitiu concluir que a Técnica Fotoplástica, utilizando as misturas de resinas poliéster CRYSTIC, é eficiente na determinação de deslocamentos e deformações plásticas em problemas de forjamento. / [en] This thesis presents the development of a material composed of mixtures of flexible and rigid polyester resins for use in Photoplasticity. Its casting precedure and mechanical and optical behavior were fully studied. The influences of mixture composition, testing temperature and loading and unloading rates on the mechanical and optical material behavior were analysed based on tensile and compressive uniaxial testing data and also through the pure bending of bars and the diametral compression of discs. For this, specimens were observed under loading and unloading and after being unloaded. The Three-dimensional Photoplastic Technique which analyses slices of unloaded but deformed models to simulate Metal Forming problems was applied to the plane compression-of bars. This same problem was studied via a non linear finite element program (NONSAP) which employed the von Mises, Tresca and Drucker-Prager yieldind criterion and also experimentally via the plane compression of aluminun bars with the purpose of comparing results. It may be conclused from these comparisons that the Photoplastic technique employing mixtures of CRYSTIC polyester resins is suitable for determining plastic displacement and plastic strains in forging problems.

Idag finns det flera hundra flamskyddsmedel på marknaden där en del är hälso- och miljöfarliga. Fytinsyra är en naturlig produkt från växtriket som är miljövänlig och icke-toxisk. Fytinsyra består till stor del av fosfor vilket gör att potential finns för ett grönt flamskyddsmedel vilket ska undersökas. Lösningar på 3 och 10 mass% fytinsyra har gjorts där sedan kalciumkloridhexahydrat, natriumhydroxid eller ammoniak med ett molförhållandet på 5 eller 12 har tillsatts. Tygbitarna, av bomull och polyester, doppades i lösningarna och torkades i 6 dagar för att sedan analyseras med ett ugnstest, förbränningstest, TGA och DSC. Bästa kombinationen för bomull blev när natrium tillsattes med ett molförhållande på 12 till 1. Denna lösning gav bäst resultat i förbränningstesten samt ger mest massa kvar enligt TGA analysen. Lösningen är även basisk vilket är bra då sura lösningar bryter ner bomullstyget. För bedömning av bästa kombinationen för polyester ligger DSC och TGA analyserna till grund. I DSC är det svårt att avgöra vilken lösning som är optimalast då natriumlösningarna höjer temperaturen för smältpunkten mycket medan effekten minskar som behövs för att smältningen ska äga rum har halverats i förhållande till obehandlad polyester. Däremot har effektförbrukningen för smältningen ökat för kalciumlösningarna medan temperaturen endast höjts någon grad. Därmed är det svårt att säga den optimala lösningen för polyester. / Today there are several hundred flame retardants on the market where some are hazardous for the health and environment. Phytic acid is a natural product from the plant kingdom, which is environmentally friendly and non-toxic. Phytic acid consists largely of phosphorus, which means that there is potential for a green flame retardant which will be investigated in this report. Solutions of 3 and 10% by weight of phytic acid were made where calcium chloride hexahydrate, sodium hydroxide or ammonia having a molar ratio of 5 or 12 were added. The cotton and polyester fabric pieces were dipped in the solutions and dried for 6 days, then analyzed by use of an oven test, a combustion test, TGA and DSC tests. The best combination for cotton was when sodium was added at a molar ratio of 12 to 1. This solution yielded the best results in the combustion test, and left the most bulk in accordance with the TGA analysis. The solution is also basic, which is good as acidic solutions break down the cotton fabric. To assess the best combination for polyester, the DSC and TGA analyzes were used. In DSC it is difficult to determine which solution is optimal as the sodium solutions raises the temperature where melting occurs by a lot, but the power needed for melting is halved relative to untreated polyester. On the other hand, the calcium solutions have increased the power needed for melting, but the melting point was raised by only some degree. Thus it is difficult to say which the optimal solution for polyester is.

Um grande crescimento no interesse por microdispositivos eletroforéticos tem sido observado nos últimos anos. Vantagens atrativas como baixo consumo de reagentes e diminutos tempos de analise são verificados. Microdispositivos fabricados usando toner de impressora e folhas de transparência (poliéster) vem a somar valores como baixo custo e simplicidade de confecção à técnica de micro-separação eletroforética. Entretanto, a aplicação analítica utilizando esse tipo de microdispositivo tem sido pouco explorada. <br />Neste trabalho o uso de microchips eletroforéticos fabricados em poliéster-toner (PT) é utilizado para a determinação simultânea do herbicida glifosato e seu maior metabólito, AMPA (ácido aminometilfosfônico). Em um primeiro momento, o trabalho apresenta o desenvolvimento de uma metodologia no qual utiliza condutometria sem contato (C4D) como sistema de detecção, aliada à separação eletroforética em microchips de PT. Vários parâmetros que regem uma boa confiabilidade analítica, tanto quanto otimizam a sensibilidade do sistema foram avaliados. <br />Em um segundo momento, ainda aliada à microchips de PT, a técnica de cronoamperometria foi utilizada como sistema de detecção. Nessa etapa do projeto estudos eletroquímicos foram inicialmente realizados em eletrodos convencionais de ouro e cobre, buscando averiguar qual metal apresenta maior sensibilidade para o herbicida glifosato. Tendo o metal cobre como melhor escolha, eletrodos planares foram construídos a partir da combinação das tecnologias da produção de máscaras de toner, e placas de circuito impresso como fonte de cobre. <br />Em ambas as metodologias desenvolvidas, picos bem resolvidos foram encontrados para os analitos em estudo. Tempos menores que 80 s foram gastos entre o processo de separação e detecção; uma boa repetibilidade também foi encontrada. Os valores de limite de detecção (LD) utilizando C4D foram 60,8 e 74,8 &micro;mol L-1 para glifosato e AMPA respectivamente. Como esperado, menores valores de LD foram obtidos na detecção amperométrica, com 1,88 &micro;mol L-1 para glifosato e 16,45 &micro;mol L-1 para AMPA. A aplicabilidade dos métodos foi verificada através da analise do herbicida e seu metabólito em amostras de água. Etapas de derivatização e pré-concentração off-line não foram usadas nesse trabalho, dessa forma os dois métodos desenvolvidos apresentaram como principais vantagens o extremo baixo custo, e a simplicidade de uso. / A large increase in interest in electrophoretic microdevices has been observed in recent years. Advantages attractive as low reagent consumption and low analytical time are checked. Microdevices fabricated using printer toner and polyester transparency sheets are the sum values as low cost and simplicity of the technique of making micro-electrophoretic separation. However, the analytical application using this type of microdevice has been little explored. <br />In this work the use of microchip electrophoresis fabricated on polyester-toner (PT) is used for the simultaneous determination of the herbicide glyphosate and its major metabolite, AMPA (aminomethylphosphonic acid). In a first moment, the work presents the development of a methodology in which the use capacitively coupled contactless conductivity detection (C4D) for determination of analytes is employed, coupled with electrophoretic separation in PT microchips. Several parameters that govern a good analytical reliability and with the intuit of optimizing the sensitivity of the system were evaluated. <br />In a second time and still allied to the PT microchips, the technique of chronoamperometry was used for detection. Electrochemical studies were initially conducted in conventional electrodes of gold and copper, looking for determine which metal is more sensitive to detect the herbicide glyphosate. Having the best choice planar copper electrodes were constructed from a combination of technologies for the production of toner masks, and printed circuit boards. <br />In both, C4D and chronoamperometric detection methodologies, well-resolved peaks were found for the glyphosate and AMPA. Time analysis of less than 80s were found including the separation and detection processes, and a good analytical repeatability was also found. The limits of detection (LOD) using C4D were 60,8 and 74,8 &micro;mol L-1 respectively for glyphosate and AMPA. As expected, lower LOD were obtained in the amperometric detection methodology, 1.9 &micro;mol L-1 for glyphosate, and 16.5 &micro;mol L-1 for AMPA. The applicability of the methods was tested by analyzing the herbicide and its metabolite in fortified water samples. Steps of derivatization and preconcentration off-line were not applied in this work, so the two methods showed as main advantages very low cost and time analysis, and simplicity of application.

Made available in DSpace on 2014-12-17T14:57:51Z (GMT). No. of bitstreams: 1 VladimirAMC_capa_ate_cap2pdf.pdf: 1064881 bytes, checksum: ad3fb45b35e0f929ffd17f2ade8f17c2 (MD5) Previous issue date: 2008-08-15 / In the manufacture of composite, textile materials are being used as reinforcement. Generally, the combination of the matrix with the textile material in the form of fibres or yarns is used depending on their distribution in the web. In the present work, in place of fibres or yarns, a knitted structure in the form of the final product which is defined as preform. The preform is weft knit manufactured with polyester filaments. In the manufacture of composite, polyester resin was used as matrix. The physical and mechanical properties as well as the formability of the weft knit were analysed. The physical and mechanical properties as well as the formability of the knitted structure were analysed. The results obtained on the analysis show that the courses and wales of the weft knit structure and the tensile properties help the formability of the structure and the impregnation of the resin. It could be clearly observed that composite structure in the direction of the courses support more tension than in the direction of the wales. In relation to the three points flexural tests it was possible to note that there was more flexion in the direction of wales, what was expected. It was also possible to note that there are other advantages such as reduction in the loss of materials used, homogeneity in the distribution of the knitted structure in the mould, reduction in the preparation time and also in the reduction in the cost of manufacture / Na fabrica??o de comp?sitos, resultados da jun??o da resina como matriz e o material t?xtil como refor?o, o material t?xtil usualmente utilizado como refor?o, est? no formato de filamentos ou fibras soltas, que s?o aplicados diretamente sobre um molde, essa distribui??o aleat?ria do material pode ocasionar pontos fracos na estrutura j? que n?o garante uma distribui??o homogenia. No presente trabalho, em vez de fios ou fibras, foi utilizada uma malha t?xtil, fabricada na forma do produto final, que defini-se como pr?-forma, melhorando a distribui??o do material sobre o molde,. Esta pr?-forma foi fabricada em malha de trama (malha Jersey) com filamento de poli?ster e a resina de poli?ster foi utilizada como matriz na fabrica??o desse comp?sito. As propriedades f?sicas, mec?nicas e formabilidade das la?adas foram analisadas. Os resultados das propriedades da malha Jersey estudadas mostram que as la?adas da malha e as propriedades tensil ajudam a formabilidade da estrutura e a facilitam a impregna??o da resina. Claramente pode-se observar que a estrutura de comp?sito na dire??o de coluna suporta maior tens?o em compara??o com a estrutura na dire??o da carreira. Com rela??o ao teste de flex?o de tr?s pontos, foi poss?vel verificar maior flex?o no sentido da carreira, o que foi esperado. Foi poss?vel pontuar tamb?m outras vantagens como a redu??o de perdas de materiais, homogeneidade na distribui??o da estrutura de malha no molde, redu??o do tempo de produ??o e barateamento nos custos produtivos

Com o advento de plataformas flutuantes dispostas em laminas d’água, cada vez mais profundas, o desenvolvimento de linhas de ancoragem mais leves, resistentes e economicamente viáveis, foram e estão sendo desenvolvidas, sendo os materiais poliméricos os mais promissores. O poliéster, pela excelente combinação de propriedades (densidade, resistência química, durabilidade, resistência mecânica, custo, etc.) tem-se mostrado como a melhor opção para profundidades de até 2.000 metros. Entretanto, a utilização de cabos poliméricos é uma tecnologia relativamente nova, pois as primeiras instalações realizadas pela Petrobras iniciaram a partir de 1997. Desde lá, muitos testes e simulações foram realizados para avaliar e confirmar o comportamento, durabilidade e segurança destes cabos. Porém, poucas informações estão disponíveis na literatura, a respeito do real comportamento de cabos que estiveram ancorados no ambiente marinho, por diferentes períodos de tempo. Dessa forma, esta dissertação tem como objetivo fornecer mais dados, a respeito da variação das propriedades de fibras constituintes de cabos de ancoragem de poliéster. Para tal, foram caracterizadas fibras virgens, fibras ensaiadas mecanicamente para controle de qualidade e fibras de cabos submersos por 3,5 e 7,0 anos. Os ensaios e as análises apresentados foram realizados para avaliar propriedades óticas (cor, brilho e opacidade), físicas (densidade linear e morfologia), térmicas (grau de cristalinidade, estabilidade térmica, etc.), químicas (composição), mecânicas (alongamento, tenacidade, módulo inicial e força de ruptura) e reológicas (viscosidade e massa molar) dos filamentos. Baseado nos resultados obtidos, pode se verificar alteração na cor (amarelamento) e aumento do brilho, opacidade, estabilidade térmica, grau de cristalinidade, viscosidade e da massa molar dos filamentos ancorados por longos períodos de tempo. Entretanto, embora haja vestígios de degradação nestas fibras, não se observou variação significativa na força necessária para rompê-las. Contudo, estas apresentaram um menor módulo inicial, alongamento e tenacidade de ruptura. / With the advent of floating platforms arranged on water in deeper depths, the development of lighter, durable and economically viable mooring lines, were and have been developed, being the polymeric materials the most promising. The polyester, due to an excellent combination of properties (density, chemical resistance, durability, strength, cost, etc.), has been considered as the best option for depths up to 2,000 meters. However, the use of polymeric cables is a relatively new technology, since the first installations performed by Petrobras took place in 1997. Since then, many simulations and tests were performed to evaluate and confirm the performance, durability and safety of such cables. Nevertheless, few information are available in the literature regarding the actual behavior of cables, that were anchored in the marine environment, for different periods of time. Thus, this dissertation aims to provide more data about the variation of the properties of fibers, which are the constituent of polyester anchoring cables. In order to achieve the goal of this dissertation, virgin fibers, mechanically tested for quality control and fiber cables submerged by 3.5 and 7.0 years were characterized. Tests and analyzes presented were conducted to evaluate optical properties (color, brightness and opacity), physical (linear density and morphology), thermal (degree of crystallinity, thermal stability, etc.), chemical (composition), mechanical (stretching, tenacity, initial modulus and breaking strength) and rheological properties (viscosity and molar mass) of filaments. Based on the obtained results, it was possible observe change in color, brightness, opacity, thermal stability, degree of crystallinity, viscosity and molar mass of filaments. However, although there are traces of degradation in the fibers, no significant variation was observed in the force required to break them. On the other hand, the fibers had a lower initial modulus, breaking elongation and toughness.