Showing papers on "Geopolymer published in 1992"

Advanced geopolymer composites

Abstract: A self-hardened, high temperature-resistant, foamed composite is described. An alkali metal silicate-based matrix devoid of chemical water has dispersed therein inorganic particulates, organic particulates, or a mixture of inorganic and organic particulates, and is produced at ambient temperature by activating the silicates of an aqueous, air-entrained gel containing matrix-forming silicate, particulates, flyash, surfactant, and a pH-lowering and buffering agent.

Process for obtaining an aluminosilicate geopolymer and products produced by this process

Abstract: Aluminosilicate geopolymers have been grouped into three classes, as a function of the Si/Al atomic ratio which can be equal to 1, 2 or 3. If the simplified notation such as is most commonly employed is adopted, the following are distinguished: The subject of the invention is the description of a process for obtaining a geopolymer of the alkali metal poly(sialate-disiloxo) class (M)-PSDS with an Si/Al ratio = 3. It consists in reacting a geopolymeric resin obtained from a reaction mixture containing: a) an aqueous solution of alkali metal silicate with a molar ratio SiO2:M2O included or equal to: whose concentration is higher than 60 % by weight and whose initial viscosity at 20 DEG C is 200 centipoises, and then increases not to exceed 500 centipoises before 5 hours at 20 DEG C; b) an alumino-silicate oxide (Si2O5.Al2O2) in which the Al cation is in (IV-V) coordination as determined by the MAS-NMR spectrum for Al, the said oxide being in a quantity such that the molar ratio Al2O3:SiO2 is included or equal to: and in then allowing the said geopolymeric resin to harden. When compared with the prior art, the fact of not being obliged to add fillers to prevent the fissuring of the geopolymeric matrix, makes it possible to preserve a very low viscosity of the geopolymeric resin and to develop its film-forming character, which is a... Original abstract incomplete.