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Many studies have shown that the formation of geopolymers proceeds according to a mechanism of dissolution-restructuring-polymerization resulting in a solid material.Nevertheless, texturing of the material is rarely studied, mainly because of the experimental difficulty to discriminate during geopolymerization alumino-silicate products, i.e.the geopolymer itself, from the alumino-silicate raw material.In this study, SAXS, SANS, rheology, conductivity measurements were used experimentally to provide fundamental new information on the phenomenology of aggregation of aluminosilicate oligomers and on their rearrangement over time within the geopolymeric matrix.A reactional mechanism was proposed.The dissolution of metakaolin leads to the liberation of aluminate and silicate, most likely in monomeric form, into solution.These species are reacting with silicates entities already existing in activating solution and form some complex mixture of alumino-silicate species increasing the visco-elastic modulus by formation of oligomers interacting to form the geopolymer network over time.This growth occurs in a volume and the interface is defined locally by nanoaggregates separating the solid from the pore solution.Water is consumed during the hydrolysis/dissolution of metakaolin and then regenerated by polycondensation reactions in the porosity of the solid geopolymer.