Patent ID: 6995105
Filing Date: 2006-02-07
Classification: C04B,C08F

Abstract:
1. A method of fluidizing or retarding the setting of a refractory composition comprising alumina cement comprising: preparing a refractory composition by admixing a refractory composition comprising alumina cement with a water-soluble copolymer wherein said water-soluble copolymer is prepared from at least two monomers selected from the group consisting of: a) 5–90% by weight of a monomer (mixture) of the formula I b) 5–90% by weight of a monomer (mixture) selected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid, vinylsulfonic acid, vinylphosphonic acid, stryrenesulfonic acid, 2-acrylamido-2-methylpropionic acid and their alkali metal, alkaline earth metal and ammonium salts and sodium methallysulfonate, or c) 5–90% by weight of a monomer (mixture) selected from the group consisting of acrylic acid, methacrylic acid, N-vinylpyrrolidone, N, N-dimethylacrylamide, acrylamide and methacrylamide and their corresponding alkali metal, alkaline earth metal and ammonium salts, as fluidizers or setting retarders for refractory compositions comprising alumina cement; wherein the water soluble copolymer is added in an amount sufficient to impart a fluidizing effect or to retard the setting of the refractory composition, wherein said refractory composition has a particle size distribution of 35% of from 1–5 mm, 30% 0.1 to 1 mm, and 35% less than 0.1 mm, and wherein said refractory composition further comprises from 1 to 100% by weight, based on the solids content of the refractory composition, of a ceramic binder that is an aluminum oxide compound.