Made available in DSpace on 2014-12-17T15:42:08Z (GMT). No. of bitstreams: 1 EliasJL_DISSERT.pdf: 3301731 bytes, checksum: ed73b5da4a7dcfb4e0f473a7c83986b2 (MD5) Previous issue date: 2013-05-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The study of polymer blends has been an alternative method in the search field of new materials for obtaining materials with improved properties. In this work blends of poly(methyl methacrylate) (PMMA) and poly(ethylene oxide) (PEO) doped with titanium dioxide (TiO2) were studied. The PEO is a polymer semicrystalline structure varying between, 70 and 84% crystallinity, while the PMMA exhibits behavior amorphous in their structure. The use of TiO2 is related to corrosion-resistant of titanium as well as good heat transfer and other characteristics. The study of these polymer blends doped TiO2 gives the properties junction organic (polymer) and inorganic (oxide) which leads to modification of the properties of the resultant material. The blends were doped TiO2 (POE/PMMA/TiO2) in different proportions of the PMMA with the PEO and TiO2 fixed. The ratios were: 90/10/0,1; 85/15/0, 1; 80/20/0,1, 75/25/0,1 and 70/30/0,1. The resulting material was obtained in powder form and being characterized by Fourier Transformed Infrared (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and Electrochemical Impedance Spectroscopy (EIS). The infrared spectra (IR) for the blends in different ratios showed a band at 1744 cm-1, characteristic of the C=O stretching, which increases in intensity with increasing PMMA composition, while in the spectrum of pure PEO this band is absent. This may suggest that the interaction is occurring between the polymers. In the micrographs of the blends also observed change in their surfaces with variation of the composition of PMMA, contributing to the change of the electrical properties of the material. The EIS data showed that the material exhibited conductivity of the order of 10-6 S.cm-1. The blend in the ratio B2(85/15/0, 1) showed better conductivity, σ = 1.56 x 10-6 S.cm-1. It was observed that the diffusion coefficient for the blends, B5(70/30/0, 1) was the largest, 1.07 x 10-6 m2.s-1. The XRD data showing that, with the variation in the composition of the PMMA blend crystallinity of the material is decreased reaching a minimum B3(80/20/0,1), and then increases again. Thermal analysis suggests that blends made from the material obtained can be applied at room temperature / O estudo de blendas polim?ricas tem sido um m?todo alternativo no campo de pesquisa de novos materiais para obten??o de materiais com melhores propriedades. Neste trabalho blendas de poli(metacrilato de metila) (PMMA) e poli(?xido de etileno) (POE) dopadas com di?xido de tit?nio (TiO2) foram estudadas. O POE ? um pol?mero de estrutura semicristalina com varia??o entre, 70 e 84% de cristalinidade, enquanto o PMMA apresenta comportamento amorfo em sua estrutura. O uso do TiO2 est? relacionado ? alta resist?ncia a corros?o do tit?nio, assim como a boa transfer?ncia de calor, al?m de outras caracter?sticas. Uma das suas aplica??es ? a fotocat?lise. O estudo destas blendas polim?ricas dopadas com TiO2 proporciona a jun??o das propriedades org?nica (pol?meros) e inorg?nica (?xido), o que leva a modifica??o das propriedades do material resultante. As blendas foram dopadas com TiO2 (POE/PMMA/TiO2) em diferentes propor??es do POE e PMMA com o TiO2 fixo. As propor??es foram: 90/10/0,1; 85/15/0,1; 80/20/0,1; 75/25/0,1 e 70/30/0,1. O material resultante obtido foi em forma de p? sendo caracterizado por Espectroscopia de Infravermelho por Transformada de Fourier (FTIR), Microscopia de Varredura Eletr?nica (MEV), Difra??o de Raios X (DRX), Termogravimetria (TG/DTG) e Espectroscopia de Imped?ncia Eletroqu?mica (EIE). Os espectros de infravermelho (IV) para as blendas em diferentes propor??es apresentaram uma banda em 1744 cm-1, caracter?stica do estiramento C=O, que aumenta de intensidade com o aumento da composi??o do PMMA, enquanto no espectro do POE puro esta banda est? ausente. Isto pode sugerir que est? ocorrendo ? intera??o entre os pol?meros. Nas micrografias das blendas, tamb?m, observa-se mudan?a em suas superf?cies com a varia??o da composi??o do PMMA o que pode contribuir na mudan?a das propriedades el?tricas do material. Os dados de EIE mostraram que o material apresentou condutividade da ordem de 10-6 S.cm-1. A blenda na propor??o B2(85/15/0,1) apresentou melhor condutividade, σ = 1,56 x 10-6 S.cm-1. Observou-se que o coeficiente de difus?o para as blendas, a B5(70/30/0,1) foi o maior, 1,07 x 10-6 m2.s-1. Os dados de DRX mostram que, com a varia??o na composi??o de PMMA na blenda a cristalinidade do material vai diminuindo atingindo um m?nimo em B3(80/20/0,1) e, ent?o, volta a aumentar. An?lise t?rmica realizada das blendas sugere que o material obtido pode ser aplicado em temperatura ambiente

The essence of this graduate thesis is to summarize knowledge about the aprotic gel electrolytes. In the graduate thesis, there are explained methods for mensuration electrochemical properties of the aprotic gel electrolytes. In the theoretical part, I focus on the knowledge related to gel polymeric electrolytes, their history, properties, mechanisms and application. In the experimental part, I describe the preparation of the samples of the gel polymeric electrolytes, in which I evaluate their properties, electrical conductivity and potencial window.