A novel mirror finishing method using a conductive polymer as the tool electrode is presented. It has been known that the conductive polymers have many advantages, such as to conduct a micro-current, to be easily processed into various shapes, to hold abrasives, and to have an excellent wear resistance. The effects of particle size, machining time, concentration of electrolyte, working current, and load on the surface roughness and the removal depth of SUS-304 stainless steel are investigated.When the operative parameters are set for the particle size of 3 £gm, the concentration of electrolyte of 10 wt%, the working current ranged from 10 to 20 mA, and the load of 10 N, the surface roughness Rmax, which originally is 1.4 £gm, can be reduced to 0.17~0.24 £gm after the machining time of 3 min. The surface roughness Ra can be achieved to 7.897 nm under the optimal condition. In addition, experimental results show that there is an optimal region of the working current at the concentration of electrolyte of 10 wt%. According to the surface profiles and SEM micrographs, three machining regions can be classified as (1) the mechanical polishing region, (2) the electro-chemical buffing (ECB) region, and (3) the excessive corrosion region. To achieve a high-quality mirror-like surface, the machining region must be operated at the ECB region.

For the last two decades, the possibility of using synthetic membranes for industrial gas separations has attracted considerable interest since membrane separation technologies have the advantages of energy efficiency, simplicity and low cost. However, for wider commercial utilization there is still a need to develop membranes with higher permeant fluxes and higher transport selectivities. Conductive polymers, due to their high gas transport selectivities, give rise to a new class of polymeric materials for membrane based gas separation though poor mechanical properties obstruct the applications for this purpose of use. This problem led researches to a new idea of combining the conducting polymers with insulating polymers forming mixed matrix composite membranes. In the previous studies in our group, polypyrrole was chosen as the conductive polymer, and different preparation techniques were tried and optimized for membrane application. As the insulating polymer, previously poly(bisphenol-Acarbonate) was used to support the conductive polymer filler in order to constitute a conductive composite membrane. For this study, as the polymer matrix, hexafluorobisphenol A based poly(arylene ether ketone) was targeted due to its physical properties and temperature resistance which can be important for industrial applications. First of all, permeabilities of N2, CH4, Ar, H2, CO2, and H2 were measured at varying temperatures ranging from 25&deg / C to 85&deg / C through a homogenous dense membrane of chosen polymeric material to characterize its intrinsic properties. Measurements were done using laboratory scale gas separation apparatus which makes use of a constant volume variable pressure technique. The permeability results were used for the calculations of permeation activation energies for each gas. These permeation activation energies were found to be differing slightly for each gas independently from the kinetic diameters of gases. In this study, mixed matrix membranes of conducting polymer, polypyrrole (PPy) and insulating polymer, hexafluorobisphenol A based poly(arylene ether ketone) (PAEK) were also prepared. It was observed that PAEK and PPy form a composite mixed matrix structure, which can function as permselective membrane. The effect of conducting polymer filler content was investigated with two different filler ratios. When comparing with the pure PAEK membranes, meaningful increases for both permeability and selectivity were obtained for some of the gases.

As técnicas de Espectroscopia de Alta Resolução em Sólidos e Relaxação por RMN são largamente utilizadas no estudo da estrutura e dinâmica de polímeros. Neste trabalho estudamos, utilizando estas técnicas, duas classes distintas de polímeros: os condutores iônicos e os condutores eletrônicos. O polímero condutor iônico estudado foi o Diesterato de Polietileno Glicol (PEGD) complexado com sais de metais alcalinos, LiClO4 ou NaClO4. A metodologia básica que empregamos para o estudo destes materiais foi a análise da forma de linha e do tempo de relaxação longitudinal para os núcleos associados tanto aos portadores de carga, 7Li e 23Na, quanto à cadeia polimérica, 1H e 13C. Todas estas medidas foram realizadas em função da temperatura e da concentração de sal de metal alcalino presente na amostra. Estudos adicionais, por condutividade elétrica, análise térmica e viscosidade foram realizados para complementar o conhecimento obtido por RMN sobre a mobilidade e estrutura das cadeias poliméricas e dos portadores de carga. Os polímeros com ligações de elétrons-\'pi\' conjugados apresentam propriedades eletrônicas especiais, particularmente a condutividade elétrica, e formam uma classe de polímeros condutores eletrônicos que podem ser facilmente oxidados ou reduzidos através de um agente dopante. Estudamos dois polímeros deste tipo: As polianilinas dopadas com 1H ou 7Li. A metodologia básica que empregamos para o estudo destes polímeros foi a análise das formas de linhas espectrais de um dos núcleos que compõem a cadeia polimérica, 13C, e de um dos agentes dopantes, 7Li, em função do método de preparação e da condutividade elétrica, de forma a poder elucidar características estruturais e dinâmicas deste grupo de polímeros. A partir do estudo destas duas classes de polímeros, conseguimos coletar uma quantidade muito grande de resultados experimentais por RMN, a partir de diferentes núcleos atômicos, que contribuíram para elucidar várias de suas características estruturais e dinâmicas / High resolution solid-state NMR spectroscopic techniques are widely used in the study of polymer structure and dynamics. In the present work we are studying, with the employment of these techniques, two distinct kinds of polymers: the ionic conductors and the electronic conductors. The ionic conductor polymer considered was the Poliethyleneglycol Distereate - 400)/MclO4, (M=Li,Na), DPEG/MclO4. The basic methodology employed for the study of these materials were the line shape analysis of the resonance lines and the longitudinal relaxation time, for the nuclei associated with the charge carriers, 7Li and 23Na, and with the polymeric chain, 1H and 13C. The measurements were related to temperature and to the alkali metal salt concentration in the sample. Additional studies, of electrical conductivity, thermal analysis and viscosity were also conducted for the complementation of the information obtained by NMR about the mobility and structure of polymeric chains and the charge carriers. The polymers with conjugated n-electron bounds present special electronic properties, particularly related to the electrical conductivity, and are easily oxidized or reduced by the action of a doping agent. We studied two of these kind of polymers: the 1H and 7Li doped Polyaniline. The basic methodology employed for the study of these polymers was the line shape analysis of the resonance lines related to one of the component nuclei of the polymeric chain, 13C , and the lines related to one of doping agents, 7Li, as a function of the preparation method and the electrical conductivity, as a way of elucidate structural and dynamic characteristics of this class of polymers. From the study of these two classes of polymers we could collect a huge quantity of NMR data from different atomic nuclei, and it led to the elucidation of important structural and dynamic characteristics of the polymers

O presente trabalho tem como objetivo o estudo e o desenvolvimento de dispositivos eletrônicos, para o monitoramento de gás de amônia, confeccionados com filmes ultrafinos de polianilina e ftalocianinas metálicas. Foram fabricados três diferentes tipos de sistemas: polianilina/PVS, polianilina/ftalocianina de níquel e polianilina/ftalocianina de cobre, sendo a espessura dos filmes o parâmetro de análise. Foram preparadas amostras com 10, 20 e 40 bicamadas. Os filmes foram caracterizados por profilometria e espectroscopia de absorção na faixa da radiação do UV - visível. Observou-se um aumento linear da espessura dos filmes com o aumento do número de bicamadas depositadas. Os dispositivos foram preparados a partir da deposição dos filmes ultrafinos de polianilina e ftalocianinas sobre substratos de vidro com eletrodos interdigitados de ouro evaporados termicamente. Os dispositivos foram caracterizados eletricamente por medidas de variação da resistência elétrica, em regime de corrente contínua e alternada, para diferentes concentrações de amônia. Também foi analisado o efeito da temperatura e da umidade relativa do ar na sensibilidade dos dispositivos. Todas as estruturas apresentaram uma dependência direta do valor da resistência elétrica com a concentração de amônia. Os dispositivos baseados em filmes de polianilina e ftalocianina de níquel apresentaram a menor variação do valor de resistência elétrica com a umidade relativa do ar. Esta característica é bastante desejável já que os ambientes nos quais se pretende utilizar este tipo de dispositivo para de monitoramento do gás de amônia, pode sofrer grandes variações no valor da umidade relativa do ar, como é o caso de granjas em geral. / The aim of this work is the study and development of electronic devices for ammonia gas monitoring based on polyaniline and metal phthalocyanines ultrathin films. It was produced three different systems: polyaniline/PVS, polyaniline/nickel phthalocyanine of and polyaniline/copper phthalocyanine and the analysis parameter of the films is the thickness. Samples were prepared with 10, 20 and 40 bilayers. The films were characterized by profilometry and spectroscopy of absorption of radiation in the range of UV-visible. There was a linear increase the thickness of the films with the increase in the number of deposited bilayers. The devices were prepared from the deposition of polyaniline and ftalocianines ultrathin films on glass substrates with interdigited electrodes of gold evaporated thermally. The devices were prepared from the polyaniline and phthalocyanine deposition of ultrathin films over glass substrates with gold interdigited electrodes. The devices were characterized electrically by measures of variation of electrical resistance, under the direct current and alternating, for different concentrations of ammonia. It was also examined the effect of temperature and relative humidity of the air in the sensitivity of the devices. All structures had a direct dependence of the value of the electrical resistance with the ammonia concentration. Devices based on films of polyaniline and nickel phthalocyanine of had the slightest variation in the amount of electrical resistance with the relative humidity. This feature is desirable because the environments in which it intends to use this type of device for tracking of ammonia gas, may undergo major changes in the value of the relative humidity of the air, such as poultry houses in general.

Au cours de cette thèse, des dispositifs électrochromes à base de polymères conducteurs électroniques ont été développés pour obtenir des systèmes pouvant passer d’un état coloré cyan, magenta ou jaune à un état incolore. Les polymères électrochromes sont des dérivés du poly(3,4-propylènedioxythiophène) (PProDOT) et du poly(3,4-éthylènedioxythiophène) (PEDOT). Un réseau de polyéthylène glycol incorporant un liquide ionique 1-éthyl-3-méthylimidazolium bis(trifluorométhylsulfonylimide) (EMITFSI) a été utilisé en tant que gel d’électrolyte. Dans un premier temps, les polymères cyan, magenta et jaunes ont été étudiés. La relation entre structure et propriétés colorimétriques des polymères cyan et jaunes a été étudiés par des calculs théoriques avec la théorie de fonctionnelle de densité, la spectroscopie UV/Vis et la colorimétrie. Ces deux dernières techniques ont également été utilisées pour l’étude des polymères magenta. Les polymères présentant les meilleures propriétés optiques ont ensuite été intégrés dans des dispositifs à deux électrodes. Ceux-ci ont été étudiées par des mesures électrochimiques pour évaluer les effets sur le fonctionnement du système et sa durée de vie. Grâce aux données obtenues, nous avons pu montrer que la stabilité des dispositifs était liée à l’efficacité coulombique des polymères cyan, magenta ou jaunes. Pour contourner l’effet de l’efficacité coulombique sur les systèmes en 2 électrodes, nous avons développé des dispositifs intégrant une pseudo-référence. L’application de ces systèmes à 3 électrodes avec un polymère cyan permet de multiplier la gamme de stabilité par 7. Finalement des démonstrateurs ont été produits avec plusieurs dispositifs de chaque couleur. / During the course of this work, electrochromic devices integrating electronically conductive polymers have been developed to obtain systems that could switch from a cyan, magenta or yellow color to an almost colorless one. The electrochromic polymers are derivatives of poly(3,4-propylenedioxythiophene) (PProDOT) and poly(3,4-ethylenedioxythiphene) (PEDOT). A network of polyethyleneglycol swollen with an ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonylimide) (EMITFSI) was used as a gel polymer electrolyte. As a first step, the cyan, magenta and yellow polymers were studied. The relationship between structure and colorimetric properties of the cyan and yellow polymers have been studied with theoretical calculation using the density functional theory, UV/Vis spectroscopy and colorimetry. These last two techniques have also been used to study the magenta polymers. The polymers with the best optical properties have then been integrated inside two electrode devices. They have been characterized with electrochemical measurement to evaluate the effects on the system and its lifetime. The data showed that the stability of the devices was linked to the reversibility of the cyan magenta or yellow polymers. As a workaround to the coulombic efficiency limitation on the 2 electrode systems, we have developed devices with a pseudo-reference. The application of those 3 electrode systems with a cyan polymer leads to a 7 fold increase of the device lifetime. Finally demonstrators have been produced with several devices of each color.

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Nesse trabalho é apresentado o estudo de redes neurais artificiais (RNAs) como sistemas de aprendizado, simulação e otimização de processos de deposição de filmes finos poliméricos. Duas técnicas de deposição comumente utilizadas para a fabricação de dispositivos eletrônicos e sensores poliméricos foram escolhidas: i) spin coating ou centrifugação e ii) automontagem. Na primeira técnica, a espessura final dos filmes finos obtidos foi a característica avaliada em função da velocidade de rotação, do tempo de rotação e da concentração da solução polimérica. Como material de deposição, utilizou-se a poli(o-metoxianilina) (POMA). Com a segunda técnica analisou-se a influência sobre a espessura, sobre a condutância elétrica e sobre o espectro de absorção, do número de bicamadas, do tempo de exposição dos filmes a uma solução dopante de ácido clorídrico (HCl) e do pH das mesmas. Os poliíons utilizados nessa técnica foram a polianilina (PAni) e o poli(vinil sulfato de sódio) (PVS). Os filmes obtidos pela segunda técnica de deposição constituem uma classe de sensores capazes de detectar e quantificar concentrações baixas de HCl diluído em água. Os treinamentos e simulações com redes neurais artificiais foram realizados apenas para a espessura dos filmes de POMA e a absorção dos filmes de PAni/PVS. Foram construídas redes neurais artificiais do tipo multilayer perceptron (MLP) utilizando o software MATLAB e o componente Neural Networks Toolbox. A reprodutibilidade e o número de neurônios contidos na camada intermediária foram avaliados. Os resultados mostram que as redes neurais artificiais treinadas fornecem boas respostas simuladas interpolando e extrapolando os valores experimentais utilizados. Como conclusão mostra-se que é possível a utilização dessa ferramenta para auxiliar a engenharia de processos, as técnicas e análises de deposições de filmes finos poliméricos. / In this work it is shown a study of artificial neural networks used as learning and simulating systems to optimize polymeric thin films deposition processes. Two common layer deposition techniques to fabricate polymeric electronic devices and polymeric sensors were chosen: i) spin coating and ii) self-assembly. In the first technique the final thickness of obtained thin films was the analyzed characteristic as a function of spin speed, spin time and solution concentration. For the deposited layers we used poly(o-methoxyaniline) (POMA). In the second technique we analyzed the influence of the number of bilayers, the pH of deposition solutions and the dipping time in the final thickness, electrical resistance and UV-Vis absorption spectra. As polyions, we used polyaniline (PAni) and poly(vinyl sodium sulfate) (PVS). These films could be used as a sensor to detect low concentrations of HCl diluted in water. After obtaining the experimental data we constructed artificial neural networks using multilayer perceptrons (MLP) architecture with MATLAB and its component called Neural Networks Toolbox. The number of neurons in the hidden layer and the reproducibility were analyzed. The results show that the trained artificial neural networks used in this work provide good simulation responses interpolating and extrapolating the experimental data. As a conclusion we show that it is possible to utilize this tool to aid the process engineering and the polymeric thin film deposition techniques and analysis

Electroactive textile fibers are key components in smart and interactive textile applications. In previous research on textile base conductive fibers, viscose fibers were coated with poly (3,4-ethylenedioxythiophne) (PEDOT) using oxidative chemical vapor deposition (oCVD) technique[1]. Ferric chloride was used as oxidant and reaction conditions were optimized at which better electrical as well as mechanical properties of conductive viscose fibers could be achieved. In this thesis work, effect of new parameters such as pretreatment of viscose fibers with solvents, drying of oxidant treated viscose fibers at different time and temperature and comparison of two different oxidants have been tried. One new and important oxidant, ferric (III) p-toluene sulfonate or ferric (III) tosylate, used to prepare PEDOT coated viscose fibers and then compared with PEDOT coated viscose fibers prepared using oxidant ferric (III) chloride. Viscose fibers have been treated with two well know solvents, acetone and ethyl acetate before soaking in oxidant solution. Oxidant enriched fibers dried at different temperature for variable time prior to polymerization step. Knitted structures of conductive viscose fibers have been prepared. Hand washing of PEDOT coated viscose fibers with tap water and machine washing of knitted structures according to the international standard ISO EN-6330 have been performed and washing effects were investigated. Effects of all of the above mentioned variables on electromechanical properties of PEDOT coated viscose fibers were studied by using tensile testing, TGA analysis, FTIR spectra and conductivity measurements. Stretch sensing properties of knitted structures; before and after washing, were determined on cyclic tester. The purpose of this study is to enhance the properties of PEDOT-coated viscose fibers by controlling different parameters and to evaluate their usage as stretch sensors as well as to check the washability of PEDOT coated viscose fibers and knitted structures. Better electromechanical properties were achieved on new parameters and PEDOT coated viscose fibers were successfully utilized as stretch sensors. PEDOT coated viscose fibers could have potential to apply in areas such as, military textiles, medical textiles and sensors. / Program: Master programme in Textile Technology