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Zugl.: Saarbrücken, Universiẗat, Diss., 1995.

La thèse est consacrée à la synthèse et à l’étude des propriétés des matériaux hybrides inorganique-organique à base de polyaniline (PANI) et de polypyrrole (PPy) avec des nanoparticules TiO2 (rutile et anatase) et SnO2 applicables à détection l'ammoniac et aux amines. La croissance directe du polymère sur la surface des nanoparticules a permis l’obtention de matériaux nanocomposites avec une structure “core-shell” qui diffère du mélange mécanique simple par une distribution plus uniforme des polymères et une interaction plus forte entre les composants source. L’objet de la recherche est le processus de formation de nanocomposites de polyaniline et de polypyrrole avec des oxydes métalliques. L’objectif de la recherche est de révéler les particularités de la formation et les propriétés des matériaux composites nanostructurés à base de polymères conducteurs et nanoparticules d’oxydes métalliques sensibles à l’ammoniac et aux amines. Les méthodes de recherche incluent le RedOx et la surveillance du pH, FTIR et UV-spectroscopie, SEM, TEM, thermogravimétrie, chromatographie liquide, mesures de conductivité et tests de capteurs. La nouvelle approche d’étude de la cinétique du processus de polymérisation de l'aniline par la surveillance simultané du RedOx et du pH du milieu réactionnel a été proposée. Pour la première fois, on a montré l’influence des acides sulfoniques et des oxydes métalliques sur le procédé de polymérisation de l’aniline et les caractéristiques moléculaires du polymère obtenu. En outre, une corrélation linéaire entre le contenu en nanoparticules et la durée réciproque des stades séparés de la polymérisation a été démontrée. Les nanocomposites “core-shell” formés ont une sensibilité à l’ammoniac et aux amines environ 2 fois supérieure à celle du polymère pur. Les nouveaux matériaux développés peuvent être utilisés dans la fabrication de couches actives des capteurs chimiorésistifs. / The thesis is devoted to the synthesis and investigation of properties of inorganic-organic polyaniline (PANI) and polypyrrole (PPy) based hybrid materials with TiO2 (rutile and anatase) and SnO2 nanoparticles applicable for ammonia and amines detection. The direct polymer growth on the surface of nanoparticles allowed obtaining of nanocomposite materials with a “core-shell” structure which differs from simple mechanical mixture by more uniform polymer distribution and stronger interaction between source components.The object of research is the process of formation of polyaniline and polypyrrole nanocomposites with metal oxides. The research goal is to reveal formation peculiarities and properties of nanostructured composite materials based on conducting polymers and metal oxides nanoparticles that are sensitive to ammonia and amines. Research methods include RedOx and pH monitoring, FTIR and UV-spectroscopy, SEM, TEM, thermogravimetry, liquid chromatography, conductivity measurements and sensor tests.The new approach to study kinetics of aniline polymerization process by simultaneous RedOx and pH monitoring of reaction medium was proposed. For the first time the influence of sulfonic acids and metal oxides on the aniline polymerization process and molecular characteristics of the obtained polymer was shown. For the first time a linear correlation between the nanoparticles content and reciprocal duration of separate stages of polymerization was shown. Formed "core-shell" nanocomposites have sensitivity to ammonia and amines of about 2 times higher than the pure polymer. Developed new materials can be used in the manufacturing of chemoresistive sensors' active layers.

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This study of the bending of a spherical shell of constant thickness consists of five chapters. In the first chapter, general differential equations of the problem are derived and presented with the variables in dimensionless form. The second chapter deals with the solution of the two second order differential equations in terms of Bessel Functions. The solution is applicable for shells with a colatitude of about 25 degrees or less. Expressions are given for the internal stresses and displacements in terms of these values at the boundary. The third chapter gives a numerical solution of the problem. Solutions are found for three cases of radius to thickness ratio, namely 30, 100 and 500, and for colatitudes from 8 to 90 degrees. In the preparation of tables the Alwac III-E Electronic Digital Computer was used. The flow diagram and programme for the Alwac III-E are given. The fourth chapter compares the numerical method with one of Timoshenko's approximate solutions. The wave lengths, deflections, rotations and moments are calculated by two methods and compared. As the conclusion to these comparisons a graph is given, which shows the approximate error in the damped harmonic solution. In the last chapter, a numerical example is solved using tables from the digital computer. The ratio of radius to thickness is 500; radius being 125 feet and the colatitude 30 degrees. The edges are considered as being on rollers. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate