Formulation de liant aluminosilicaté de type géopolymère à base de différentes argiles Tunisiennes

Ce travail est basé sur la formulation d un liant aluminosilicaté de type géopolymère à partir de différentes argiles tunisiennes. Afin de comprendre les mécanismes de formation à l origine de la consolidation des matériaux. Une première étape a concerné la caractérisation des matières argileuses par différentes méthodes d analyses ainsi que leur comportement vis-à-vis de la température. La faisabilité des matériaux consolidés a été étudiée, dans un second temps, afin de mettre en exergue le rôle des minéraux associés et le taux d amorphisation sur les propriétés des produits obtenus. L élaboration d un matériau modèle à base du kaolin d Imerys et l oxyde de fer a permis d appréhender le rôle des minéraux associés (oxyde de fer) sur les réactions de polycondensation. Plusieurs techniques ont été utilisées pour caractériser les matériaux au cours de leur formation par spectroscopie infrarouge et après consolidation par diffraction des rayons X, microscopie électronique à balayage, résonnance magnétique nucléaire et analyse thermique. Leurs propriétés mécaniques ont été testées par compression.This study is based on the formulation of an aluminosilicate geopolymer type from different Tunisian clays. To understand the formation mechanisms behind the consolidation of materials. A first step has involved the characterization of clay materials by different methods of analysis and their behavior versus temperature. In parallel, The feasibility of consolidated materials was studied in order to highlight the role of associated minerals and the rate of amorphous compound on the properties of materials. The mixture of kaolin Imerys and iron oxide has been investigated to propose a model of these materials. Several techniques have been used to characterize materials in situ by infrared spectroscopy and after consolidation by X-ray diffraction, scanning electron microscopy, nuclear magnetic resonance and thermal analysis. Their mechanical properties were evaluated by compression.LIMOGES-BU Sciences (870852109) / SudocSudocFranceF

Defining existence domains in geopolymers through their physicochemical properties

International audienceGeopolymeric material is a new type of cement that is synthesized through the alkali activation of aluminosilicates. To improve the properties of the aluminosilicates, the composition is greatly modified. However, through numerous possible synthetic routes to form geopolymers, the determination that the final material has a geopolymer network cannot be ensured, despite the apparent or partial consolidation of material. This work proposes a definition that a domain in the geopolymeric material exists that can be correlated using different techniques to quantify the amount of silicon, potassium and aluminum. Two sources of potassium silicate and various clays with different degrees of amorphous character were compared to determine the importance of the starting materials. The existence domain is an important tool to determine if the synthesized material is a geopolymer network independent of the raw materials used

Zirconia based geopolymer matrix to reduce antenna size

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Comparative study of dielectric properties of geopolymer matrices using different dielectric powders

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New Ultra Wide Band antenna design with innovative materials

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Physical-chemical characterization of Tunisian clays for the synthesis of geopolymers materials

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