Abstract: The present invention provides a dispersion-retaining agent for a hydraulic composition being excellent in both fluidity retainability and viscosity retainability and further a dispersion-retaining agent exhibiting fluidity retainability and viscosity retainability regardless of the type of hydraulic powder. The present invention relates to a dispersion-retaining agent for a hydraulic composition, containing a copolymer obtained by polymerizing specific monomer 1 represented by formula (1), with monomer 2 represented by formula (2), the corresponding alcohol compound of which satisfies specific physical properties, wherein, in the constituent monomers of the copolymer, the proportion of the monomer 1 is in a specific range, a specified monomers is used as at least a part of the monomer 2, and the proportion of monomers having an acid group or a neutralized group thereof is 5% by weight or less.

Abstract: Method for producing phosphoric acid ester-based polymer by copolymerizing monomer 1 of formula (1), monomer 2 of formula (2), and monomer 3 of formula (3): wherein the variables are as defined in the specification; wherein the variables are as defined in the specification; and wherein the variables are as defined in the specification, at pH ?7 in solvent having dissolved oxygen concentration of 0.01-4.0 mg/kg, or in presence of phosphonic acid-based chelating agent, or by mixing monomers 1 to 3 at 10-50 ° C., initiating polymerization within 72 hours, and maintaining the temperature at 10-50 ° C. until polymerization is initiated. The phosphoric acid ester-based polymer may be used as a dispersant in a hydraulic composition.

Abstract: The present invention provides a dispersion-retaining agent for a hydraulic composition being excellent in both fluidity retainability and viscosity retainability and further a dispersion-retaining agent exhibiting fluidity retainability and viscosity retainability regardless of the type of hydraulic powder. The present invention relates to a dispersion-retaining agent for a hydraulic composition, containing a copolymer obtained by polymerizing specific monomer 1 represented by formula (1), with monomer 2 represented by formula (2), the corresponding alcohol compound of which satisfies specific physical properties, wherein, in the constituent monomers of the copolymer, the proportion of the monomer 1 is in a specific range, a specified monomers is used as at least a part of the monomer 2, and the proportion of monomers having an acid group or a neutralized group thereof is 5% by weight or less.

Abstract: The present invention relates to a method for producing a phosphoric acid ester-based polymer, including copolymerizing a monomer 1 represented by the following formula (1), a monomer 2 represented by the following formula (2), and a monomer 3 represented by the following formula (3), at pH 7 or lower, in the present of a polymerization solvent having a dissolved oxygen concentration at 25° C. of 0.01 to 4.0 mg/kg. The invention also relates to a method for producing a phosphoric acid ester-based polymer, including copolymerizing the monomers 1, 2 and 3 at pH 7 or lower, in the presence of a phosphonic acid-based chelating agent. The invention also relates to a method for producing a phosphoric acid ester-based polymer from a mixed solution containing the monomer 1, 2 and 3, including obtaining a mixed solution by mixing the monomers 1 to 3 at a temperature of 10 to 50° C.

Abstract: The invention provides an additive for hydraulic compositions, which exhibits an excellent viscosity reducing effect on a hydraulic composition, for example, a hydraulic composition containing a slurry of water and hydraulic powder, and is excellent in operativeness when used as an aqueous solution. The additive for hydraulic compositions contains a phosphoric monoester having a specific group such as an alkyl ether group or a salt thereof (monoester) and a phosphoric diester having a specific group such as an alkyl ether group or a salt thereof (diester) in a monoester weight content of monoester/(monoester+diester) is 0.4 to 0.95 (diester includes a pyrodiester).

Abstract: The invention provides a process wherein a dispersant for a hydraulic composition capable of conferring an excellent dispersing effect and a viscosity reducing effect on a hydraulic composition can be produced at an industrially practical level. A phosphate polymer preferable as a dispersant for a hydraulic composition is obtained by copolymerization of a specific monomer 1 having a polyoxyalkylene group, a phosphoric monoester monomer 2 and a phosphoric diester monomer 3 at pH 7 or less.

Abstract: The invention provides an additive for hydraulic compositions, which exhibits an excellent viscosity reducing effect on a hydraulic composition, for example, a hydraulic composition containing a slurry of water and hydraulic powder, and is excellent in operativeness when used as an aqueous solution. The additive for hydraulic compositions contains a phosphoric monoester having a specific group such as an alkyl ether group or a salt thereof (monoester) and a phosphoric diester having a specific group such as an alkyl ether group or a salt thereof (diester) in a monoester weight content of monoester/(monoester+diester) is 0.4 to 0.95 (diester includes a pyrodiester).

Abstract: An admixture for concrete comprising, as an essential component, a copolymer prepared by copolymerizing (a) a polyalkylene glycol monoester monomer having 110 to 300 mols of an oxyalkylene group(s) each having 2 to 3 carbon atoms, with (b) at least one monomer selected from among acrylic monomers, unsaturated dicarboxylic monomers and allylsulfonic monomers. When this admixture is used in preparing concrete, the resulting concrete composition undergoes little change in the slump for a lengthened time, so that the quality of the concrete composition can be easily controlled.

Abstract: Cement and aggregates are mixed with each other by the use of a dispersant to the effect of water reduction and prevention of slump loss, the dispersant comprising (1) (I), (IIa), and an amine reaction terminator of (IIb), (IIc), (IVg) and/or (IVh); (2) (I), (IIb) and/or (IIc) and (IIIe) and/or (IIIf); or (3) (I), (IIa) and (IIIe) and/or (IIIf), in which formulae, R is hydrogen or an alkyl having 1 to 6 carbon atoms; X is an alkali metal; X.sub.1 is hydrogen, an alkyl having 1 to 6 carbon atoms, carboxylic acid group, an alkali metal salt carboxylate, sulfonic acid group, an alkali metal salt sulfonate, hydroxy or methoxy; Y.sub.1 is carboxylic acid or an alkali metal salt carboxylate, sulfonic acid or an alkali metal salt sulfonate; Y is hydrogen or an alkali metal; Z is hydrogen, an alkyl having 1 to 6 carbon atoms or --CH.sub.2 SO.sub.3 M; and M is hydrogen or an alkali metal.

Abstract: An aqueous dispersant composition for cement comprises 100 parts by weight of a copolymer of an olefin having 2 to 8 carbon atoms and an ethylenically unsaturated dicarboxylic anhydride, the copolymer being in the form of fine particles having an average size of 0.1 to 20 micrometers, 15 to 300 parts by weight, of zinc, as zinc oxide or zinc hydroxide, and water, the composition being adjusted to have a pH value of 6 to 12.