摘要:
A method of retarding the set time of a cement composition comprising providing a cement composition that comprises water and a cement, and retarding the set time of the cement composition by including a copolymer retarder in the cement composition, wherein the copolymer retarder comprises olefinically unsaturated non-acrylate sulfonate monomers and olefinically unsaturated carboxylic acid monomers. Methods of cementing in a subterranean formation also are provided.
摘要:
Amine solubilizing agents are mixed with water insoluble defoamers and optionally a dispersant for cementitious compositions to provide an admixture for cementitious compositions that is stable over time. A method is provided for controlling the amount of air in a cementitious material in a predictable manner that includes mixing cementitious material, water, a water insoluble defoamer, an amine salt solubilizing agent that solubilizes the water insoluble defoamer, and optionally a dispersant for cementitious compositions.
摘要:
Improved fluid loss control additives for use in cement compositions are provided. The improved fluid loss control additives and cement compositions are suitable for use in surface and subterranean applications. The improved fluid loss control additives and cement compositions may be particularly useful for subterranean well completion and remedial operations, such as primary cementing, e.g., cementing casings and liners in well bores, including those in production wells, which include multi-lateral subterranean wells. They also may be useful for surface cementing operations, including construction cementing operations. Examples of compositions include fluid loss control additives.
摘要:
Methods of combining water-in-oil emulsion polymers with aqueous saline well treating fluids and compositions are provided. A composition of the invention basically comprises hydraulic cement, an aqueous saline fluid sufficient to form a slurry, a polymer precipitation and coagulation preventing surfactant, and a water-in-oil emulsion polymer.
摘要:
Cementitious compositions comprising pozzolonic materials, alkaline earth metals, and a catalysts to catalyze the reaction between the pozzolonic materials and the alkaline earth metals.
摘要:
A cold-weather admixture composition that accelerates the setting time and strength development of cementitious compositions is provided which comprises the components of a soluble inorganic salt having freezing point depressing properties, an inorganic early set and strength accelerator, a polycarboxylate high range water reducing dispersant, and an organic set accelerator. With lower dosages of dispersant than those disclosed in the prior art the admixture composition provides to concrete increased dispersant performance and acceleration of setting time and strength development.
摘要:
A process for increasing the viscosity of an aqueous cementitious mixture during its working state by mixing oppositely-charge polyelectrolytes into the cementitious mixture.
摘要:
A water-redispersible powder composition comprising: at least a water-soluble film forming polymer, the polymer being prepared from at least an ethylenically unsaturated monomer; and at least a naphthalenesulphonate.
摘要:
A cementitious formulation comprising a cement and an oligomeric dispersant is provided. The dispersant is a reaction product of two or three moieties. The first moiety (A) is a nonpolymeric, functional moiety that adsorbs onto a particle, and wherein one or more A moieties together contain at least two residues to provide attachment of the dispersant onto a particle to be dispersed. The second required moiety (C) is a linear or branched water soluble, nonionic polymer that provides the dispersing capability. A third moiety (B), if present, is a nonpolymeric moiety disposed between the first and second moiety, to connect the first and second moieties. A method is provided for dispersing a cementitious formulation comprising a cement in water, including providing in said cementitious formulation the above oligomeric dispersant. A combination of any cement dispersant with an oligomeric dispersant wherein at least one A moiety is blocked is also provided in a cementitious formulation and in a method of making such cementitious formulation.
摘要:
A cement additive is added to increase flowability of a cement composition and to prevent a slump loss, but those characters are insufficient, or the cement additive becomes ununiform in the cement composition and causes a trouble of the hardening inferiority. Thus, to solve the subjects, the present invention provides a cement additive composed of a crosslinked polymer in which, between main chains having a water-soluble polymer structure of a molecular weight from 500 to 100,000, a bond having as a structural unit at least one group selected from divalent groups as shown in the following formula (I) is formed. ##STR1## �In the formula (I), R.sup.1 and R.sup.2 independently denote any one of the following. ##STR2## However, R.sup.1 may not be required in a case of that R.sup.2 is the following. ##STR3## Moreover, R and R' independently denote an alkyl group of carbon number of 1 to 5.!