POLIELECTROLIT

Author: BLAZQUEZ MARTIN JOSE ALBERTO.
Year: 2005.
University: PAÍS VASCO [www.ehu.es].
Place of defense: FACULTAD DE QUÍMICA (SAN SEBASTIÁN).
Place of preparation: FACULTAD DE QUÍMICA (SAN SEBASTIAN).

Summary: Fuel cells based on hydrogen or methanol is one of the alternatives being considered wing in finding technologies to reduce our dependence on fossil fuels such as coal or oil. In these batteries requiring the participation of a solid electrolyte that allows the passage of protons that are required for the reaction to occur oxidation / reduction involved in the process. Although there are different types of fuel cells as a function of solid electrolyte used, such as those using polymeric membranes capable of such transport protónico are those who have broken into the market with more force. In this thesis describes the synthesis and properties of a series of polinaftaliimidas sulfonadas, copolymers with the same methacrylate demetilo and copolymers latter with sulfometacrilato methacrylate monomer. This is different attempts to search for polymers alternative to existing today in the market, basically consisting of fluoropolímeros sulphonated, quite expensive and some deficiencies in terms of being used at high temperatures. In the narrative of the new materials obtained emphasizes processing the same with regard to obtaining the appropriate end for the actual implementation, as well as the choice of solvent used in the process. From this perspective membranes were generated based on a diamina not sulfonada quite flexible, which has helped increase its solubility in solvents less harmful to the environment that employees so far. Its conductive properties are quite similar to others described in the literature. The same objective has been achieved through the preparation of membranes hybrid organic / inorganic using other families polemizas and acid fosfotungsténico. In this case, new materials obtained show a better water absorption, resulting in improved properties transport protónico, which allows their behavior was much closer or even improve the Nafion 112, the polymer to beat in these applications. Finally, it has been investigated to obtain low-cost membranes based copolymers sulfopropil methacrylate. Such structures can result in solid electrolytes likely to be used in low-temperature applications and reduced cost.

Author: MARCILLA GARCÍA REBECA.
Year: 2005.
University: PAÍS VASCO [www.ehu.es].
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA (SAN SEBASTIÁN).

Summary: The Liquid Iónicos (LIs) are asymmetric organic salts with low boiling points (less 100Â ° C). The chemical nature of these compounds makes possessing some very attractive properties such as: high thermal stability, high ionic conductivity, electrochemical and wide window. The applications of these compounds cover a broad range: from 'green solvents' reactions in organic electrolytes up for applications in sensors or devices electrocrómicos among others. Some of the applications of LIs, especially its role in electrochemistry, the latest research is directed toward the search for solid materials that exceed some of the disadvantages inherent in the use of fluids in such applications. Over the project's development Doctoral Thesis were synthesized polymers with chemical structure similar to that of ionic liquids (LIs) for the first time describing the method of synthesis of a wide variety of policationes with different contra-anión through a anion exchange reaction that is well known in chemistry and the Lis. The use of this type of reaction in the synthesis of polymers has led to polymeric ionic liquids, both linear and microparticles of the same, with promising applications in the field of Electroquímica and at the Nanotechnologies. In nanotechnology, has developed a method of transferring nanoobjetos an aqueous medium to another organic, which also allowed us to get nanocomposites consisting of a polymer matrix of LIPs and nanoobjetos dispersed. Moreover, these LIPs have been used in the synthesis of organic polymer dispersions drivers leading to films drivers with good properties. On the other hand, in terms of electrochemical applications include the development of polymeric electrolytes and their use in devices electrocrómicos. It has been shown that these electrolytes based LIPs offer better benefits to the device that traditionally used electrolytes. In addition they have used the LIPs reticulados synthesized in Chapter I as a polymeric support of the enzyme glucose oxidase GOx. The immobilized enzyme in microparticles of LIPs, has been used as a biological component of a sensor amperométrico detection of glucose, offering a smooth operation.