Hydraulic composition, cured product, and method for producing hydraulic composition

Abstract

To provide a hydraulic composition capable of achieving a cured product having sufficiently high compressive strength and low water absorption.SOLUTION: A hydraulic composition comprises (A) cement and (B) a forced emulsification type urethane resin emulsion having an urethane resin. The content of the urethane resin satisfies at least one selected from the group consisting of the following conditions (1) and (2). (1) It is 25 pts.mass or less based on 100 pts.mass of the cement (A). (2) It is 7 mass% or less based on the total amount of 100 mass% of the hydraulic composition.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a hydraulic composition, a hardened product, and a method for producing a hydraulic composition. [Background technology]

[0002] Conventionally, methods that have been proposed for the surface of architectural and civil engineering concrete structures to prevent deterioration of the structure due to water infiltration and water leakage into the interior include coating with polymer cement, coating with mortar containing siliceous waterproofing agents, and injection, penetration and coating coating methods using organic resins, cement-based or water glass-based materials.

[0003] For example, the technology described in Patent Document 1 involves applying a thin layer of adhesive such as a urethane resin onto a resin coating waterproof layer (urethane waterproof layer) containing a urethane resin, and then laying down an EVA (ethylene vinyl acetate copolymer) thermoplastic resin sheet. A deck waterproof structure using a urethane waterproof layer is configured by sequentially laminating a primer resin layer, a urethane waterproof layer, a urethane resin adhesive layer, and an EVA thermoplastic resin sheet. In a deck waterproof structure configured in this way, after forming the primer resin layer and the urethane waterproof layer, the base agent / curing agent (isocyanate / polyol) of the urethane resin adhesive are mixed at the construction site, the mixture is applied thinly and uniformly with a roller brush or the like, and the thermoplastic resin sheet is laid down evenly to perform construction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3956757 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the cement-based hardened products obtained by hardening conventional polymer cements, etc., have problems in that they are insufficient in strength and have high water absorption, and are therefore susceptible to deterioration due to underwater fatigue. Therefore, the present disclosure provides a hardened product having sufficiently high compressive strength and low water absorption, as well as a hydraulic composition capable of obtaining such a hardened product, and a method for producing the same. [Means for solving the problem]

[0006] One aspect of the present disclosure provides a hydraulic composition comprising (A) cement and (B) a forced emulsification type urethane resin emulsion containing a urethane resin, the content of the urethane resin satisfying at least one selected from the group consisting of the following conditions (1) and (2): A hardened product of such a hydraulic composition has sufficiently high compressive strength and low water absorption. (1) The above (A) is 25 parts by mass or less per 100 parts by mass of cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition.

[0007] One aspect of the present disclosure provides a set product of the hydraulic composition, which has sufficiently high compressive strength and low water absorption.

[0008] One aspect of the present disclosure provides a method for producing a hydraulic composition, comprising the step of obtaining a hydraulic composition by mixing (A) cement with (B) forced emulsification type urethane resin emulsion in which a urethane resin obtained by a polymerization reaction of (C) polyhydric alcohol and (D) polyisocyanate is dispersed in water, wherein the content of the urethane resin in the hydraulic composition satisfies at least one selected from the group consisting of the following conditions (1) and (2): The hardened product of the hydraulic composition obtained by such a production method has sufficiently high compressive strength and low water absorption. (1) The above (A) is 25 parts by mass or less per 100 parts by mass of cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition. Effect of the Invention

[0009] The present disclosure can provide a set product having sufficiently high compressive strength and low water absorption, as well as a hydraulic composition capable of obtaining such a set product, and a method for producing the same. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present disclosure will be described. However, the following embodiments are examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following contents. The upper or lower limit of the numerical range specified in this disclosure may be replaced with any value shown in the examples. In addition, the upper and lower limit values ​​described individually may be arbitrarily combined. Unless otherwise specified, the materials or components exemplified in this disclosure may be used alone or in combination of two or more types. In the description, the same symbols are used for the same elements or elements having the same functions, and duplicate descriptions are omitted.

[0011] A hydraulic composition according to one embodiment includes (A) cement (hereinafter sometimes referred to as "component (A)") and (B) forced emulsification type urethane resin emulsion (hereinafter sometimes referred to as "component (B)") containing a urethane resin, and the content of the urethane resin satisfies at least one selected from the group consisting of the following conditions (1) and (2). A hardened product of such a hydraulic composition has sufficiently high compressive strength and low water absorption. (1)(A) Not more than 25 parts by mass per 100 parts by mass of cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition.

[0012] Regarding condition (1), the content of the urethane resin may be 25 parts by mass or less, 20 parts by mass or less, or 10 parts by mass or less, relative to 100 parts by mass of the (A) component. The content of the urethane resin is not particularly limited as long as it is not 0 parts by mass, since the above effect can be obtained even if it is very small, and may be 0.01 parts by mass or more, 0.05 parts by mass or more, 0.1 parts by mass or more, or 1 part by mass or more, relative to 100 parts by mass of the (A) component. The content of the urethane resin in the present disclosure is a value as a solid content.

[0013] Regarding condition (2), the content of the urethane resin may be 7% by mass or less, or 6% by mass or less, relative to 100% by mass of the total amount of the hydraulic composition. Since the above effect is achieved even with a very small content of the urethane resin, there is no particular limitation as long as it is not 0% by mass, and the content may be 0.01% by mass or more, 0.05% by mass or more, or 0.1% by mass or more, relative to 100% by mass of the total amount of the hydraulic composition.

[0014] [cement] The hydraulic composition contains cement as component (A). The cement is not particularly limited, and one or more types may be selected from Portland cements such as ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, moderate-heat Portland cement, low-heat Portland cement, and sulfate-resistant Portland cement; mixed cements such as blast-furnace cement, fly ash cement, and silica fume cement; and other cements such as ecocement, ultra-high-speed hardening cement, alumina cement, phosphate cement, and air-hardening cement.

[0015] [water] The water contained in the hydraulic composition is not particularly limited, and may be, for example, tap water, distilled water, deionized water, etc. The water may include water added when preparing the (B) component and water added when preparing the hydraulic composition. The content of water in the hydraulic composition may be 20 to 100 parts by mass, 25 to 80 parts by mass, or 30 to 70 parts by mass relative to 100 parts by mass of cement. The content of water in the forced emulsification type urethane resin emulsion may be 75 to 2250 parts by mass, 100 to 1500 parts by mass, 200 to 1250 parts by mass, or 250 to 1000 parts by mass relative to 100 parts by mass of the urethane resin solid content.

[0016] [Forced emulsification type urethane resin emulsion] The hydraulic composition contains a forced emulsification type urethane resin emulsion as component (B). In the present disclosure, the "forced emulsification type urethane resin emulsion" refers to an emulsion in which a urethane resin is added to water and the urethane resin is forcedly dispersed in the water by stirring. That is, the forced emulsification type urethane resin emulsion contains water (or an aqueous solution) as a continuous phase and particles containing a urethane resin. Stirring may be performed by hand stirring, mechanical stirring such as a homogenizer, or high-pressure homogenizer. In the forced emulsification type urethane resin emulsion, the urethane resin particles may be dispersed with high uniformity. The forced emulsification type urethane resin emulsion may contain a surfactant. The surfactant plays a role of improving the hydrophilicity of the hydrophobic part of the side chain of the urethane resin and stably dispersing the urethane resin in water. By adding a surfactant, the forced emulsification type urethane resin emulsion can be prepared even with slow stirring.

[0017] The solid content concentration of the urethane resin contained in the forced emulsification type urethane resin emulsion may be 5% by mass or more, or may be 7% by mass or more. When the solid content concentration of the urethane resin is in this range, the homogeneity of the urethane resin in the emulsion can be improved. In addition, the solid content concentration of the urethane resin may be 65% by mass or less, or may be 60% by mass or less. When the solid content concentration of the urethane resin is in this range, aggregation of the urethane resin in the emulsion can be suppressed.

[0018] The content of the forcibly emulsified urethane resin emulsion as component (B) in the hydraulic composition may be 10 parts by mass or more, or may be 11 parts by mass or more, relative to 100 parts by mass of the hydraulic composition. When the content of the forcibly emulsified urethane resin emulsion is within this range, the water absorption of the cured product can be further reduced. In addition, the content of the forcibly emulsified urethane resin emulsion may be 25 parts by mass or less, or may be 20 parts by mass or less, relative to 100 parts by mass of the hydraulic composition. When the content of the forcibly emulsified urethane resin emulsion is within this range, excellent kneadability can be obtained, and a cured product with sufficiently high strength can be obtained.

[0019] On the other hand, in this disclosure, "self-emulsifying urethane resin emulsion" refers to an emulsion in which a urethane resin having a hydrophilic functional group added to the side chain structure is dispersed in water. A self-emulsifying urethane resin emulsion differs from a forced emulsifying urethane resin emulsion in that the urethane resin can be dispersed in water without adding a surfactant and without applying an external force such as stirring. The forced emulsifying urethane resin emulsion can disperse the urethane resin more thoroughly in the hydraulic composition than the self-emulsifying urethane resin emulsion. Therefore, in this disclosure, a forced emulsifying urethane resin emulsion is used.

[0020] [Polyhydric alcohol] The hydraulic composition may contain a polyhydric alcohol as component (C). Component (C) may be added when preparing component (B), or may be added when preparing the hydraulic composition separately from component (B). The polyhydric alcohol is a compound having two or more alcoholic hydroxyl groups in the molecule. Component (C) is not particularly limited as long as it is a compound having multiple hydroxyl groups in the molecule, and examples of the compound include aliphatic polyhydric alcohols (hydrocarbon compounds in which multiple hydrogen atoms are substituted with hydroxyl groups), polyether polyols, polyester polyols, castor oil or its derivatives, polybutadiene polyols, and alkanolamines. The number of hydroxyl groups in one molecule of the polyhydric alcohol may be 2 to 6, 2 to 5, 2 to 3, or 2. The number of hydroxyl groups may be the average value (number average) per molecule, and in this case, the number may be a rational number. Component (C) may be an unreacted product in the production of the urethane resin contained in component (B), or may be added separately from the unreacted product in the production of the urethane resin.

[0021] The polyhydric alcohol may contain at least one selected from the group consisting of an ether bond and an ester bond. Examples of polyhydric alcohols containing an ether bond include diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, diglycerol, triglycerol, and polyglycerol. Examples of polyhydric alcohols containing an ester bond include compounds produced by reacting a polycarboxylic acid with the above-mentioned polyhydric alcohol containing an ether bond. Specific examples include polyester polyols and polyester polycarbonate polyols.

[0022] The polyhydric alcohol may contain at least one compound selected from the following (C1) to (C3). (C1) Ethylene oxide or propylene oxide adducts of dihydric alcohols. (C2) Dihydric alcohols having a molecular weight of 200 or less (hereinafter also referred to as short-chain dihydric alcohols). (C3) Ethylene oxide adducts or propylene oxide adducts of trihydric or higher alcohols.

[0023] As the component (C1), an ethylene oxide adduct of polypropylene glycol is preferred from the viewpoint of imparting hydrophilicity to the urethane resin described below. The mass ratio of the ethylene oxide unit to the propylene oxide unit (EO / PO mass ratio) in such an adduct is preferably 10 / 90 to 90 / 10, more preferably 15 / 85 to 80 / 20.

[0024] Examples of the (C1) component include Actocol ED28 (manufactured by Mitsui Chemicals SKC Polyurethanes, Inc.; number average molecular weight 4000, EO / PO mass ratio: 20 / 80), Actocol ED36 (manufactured by Mitsui Chemicals SKC Polyurethanes, Inc.; number average molecular weight 3600, EO / PO mass ratio: 78 / 22), and Actocol ED56 (manufactured by Mitsui Chemicals SKC Polyurethanes, Inc.; number average molecular weight 2000).

[0025] The molecular weight of the (C2) component may be not more than 180, or may be not more than 150. Specific examples of the (C2) component include aliphatic dihydric alcohols such as ethylene glycol, propylene glycol, 1,4-butanediol, and 1,6-hexanediol, and dialkylene glycols such as diethylene glycol and dipropylene glycol.

[0026] The component (C3) is a compound having a structure obtained by carrying out a ring-opening addition reaction of ethylene oxide or propylene oxide using a trihydric or higher alcohol as an initiator, and does not have to be actually produced by ring-opening addition of ethylene oxide or propylene oxide as long as it has the same structure as that obtained by the ring-opening addition reaction. It has the effect of reducing the water solubility of the urethane resin described below.

[0027] Examples of the trihydric or higher alcohol include trihydric alcohols such as glycerin and trimethylolpropane, and trihydric or higher alcohols such as pentaerythritol, dipentaerythritol, sorbitol, monosaccharides or polysaccharides (e.g., sucrose). Among these, trihydric alcohols are preferred, and glycerin is more preferred. Only one type of trihydric alcohol may be used, or two or more types may be used in combination.

[0028] The number average molecular weight (Mn) of the (C3) component is preferably 300 to 7000, more preferably 500 to 6500, further preferably 1000 to 6000, and particularly preferably 2000 to 6000, from the viewpoint of reducing the water absorption property of the cured product formed from the hydraulic composition.

[0029] Examples of the (C3) component include EXCENOL 430 (Mn=430), EXCENOL 1030 (Mn=1000), EXCENOL 3030 (Mn=3000), EXCENOL 4030 (Mn=4000), and EXCENOL 5030 (Mn=5100) (all manufactured by AGC Corporation).

[0030] [Polyisocyanate] The hydraulic composition may contain a polyisocyanate as component (D). Component (D) may be added when preparing component (B), or may be added when preparing the hydraulic composition separately from component (B). The polyisocyanate (D) is not particularly limited as long as it has two or more isocyanate groups in the molecule, and may contain at least one selected from the group consisting of aromatic polyisocyanates and aliphatic polyisocyanates. Specific examples of the component (D) include phenylene diisocyanate, 1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, 1-methyl-2,5-phenylene diisocyanate, 1-methyl-3,5-phenylene diisocyanate, 1-ethyl-2,4-phenylene diisocyanate, 1-isopropyl-2,4-phenylene diisocyanate, 1,3-dimethyl-2,4-phenylene diisocyanate, 1,3-dimethyl-4,6-phenylene diisocyanate, 1,4-dimethyl-2,5-phenylene diisocyanate, diethylbenzene diisocyanate, diisopropylbenzene diisocyanate, 1-methyl-3,5-diethylbenzene diisocyanate, 3-methyl-1, Aromatic polyisocyanates such as 5-diethylbenzene-2,4-diisocyanate, 1,3,5-triethylbenzene-2,4-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methyl-naphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1-dinaphthyl-2,2'-diisocyanate, biphenyl-2,4'-diisocyanate, biphenyl-4,4'-diisocyanate, 3-3'-dimethylbiphenyl-4,4'-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, and diphenylmethane-2,4-diisocyanate;Tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene diisocyanate, 1,3-di(isocyanatemethyl)cyclohexane, 1,4-di(isocyanatemethyl)cyclohexane, lysine diisocyanate, It may be an aliphatic polyisocyanate or alicyclic polyisocyanate such as isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4'-dicyclohexylmethane diisocyanate, 2,2'-dicyclohexylmethane diisocyanate, 3,3'-dimethyl-4,4'-dicyclohexylmethane diisocyanate, a carbodiimide-modified isocyanate, polymethylene polyphenyl polyisocyanate, etc. These polyisocyanates may be used alone or in combination of two or more kinds. Among these, in the case of use as a shoe seat, the composition is applied on the concrete constituting the bridge pier, so that from the viewpoints of mechanical strength and adhesiveness, aromatic polyisocyanates are preferred, aromatic diisocyanates are more preferred, and at least one of toluene diisocyanates (1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, and 1-methyl-2,5-phenylene diisocyanate) is even more preferred. The (D) component may be an unreacted material when the urethane resin contained in the (B) component is produced, or may be added separately from the unreacted material when the urethane resin is produced. The polyisocyanate compound may not be contained in the hydraulic composition, and the content thereof may be 25 parts by mass or less, 10 parts by mass or less, or 5 parts by mass or less relative to 100 parts by mass of the urethane resin.

[0031] [Urethane resin] The urethane resin contained in component (B) may be a polymerization reaction product obtained by carrying out a polymerization reaction (sequential polymerization) between a hydroxyl group of a polyhydric alcohol as component (C) and an isocyanate group of a polyvalent isocyanate as component (D), and may have residues of the polyhydric alcohol and residues of the polyvalent isocyanate. The urethane resin contains a polyurethane compound having two or more urethane bonds in the molecule, and may optionally contain a monourethane compound having one urethane bond in the molecule.

[0032] Such a urethane resin may be contained in a partial polymer obtained by heating a mixture of raw materials (C) polyhydric alcohol and (D) polyisocyanate. In the partial polymer, all of the polyhydric alcohol and polyisocyanate contained in the mixture are not completely reacted, and the partial polymer may contain, in addition to the urethane resin, a part of the raw materials polyhydric alcohol or polyisocyanate that remain unreacted.

[0033] Regarding the urethane resin, the ratio [NCO] / [OH] of the total molar amount (expressed as [OH]) of the hydroxyl groups (i.e., the hydroxyl groups of the polyhydric alcohol as a raw material) that (C) the polyhydric alcohol has before the reaction to the total molar amount (expressed as [NCO]) of the isocyanate groups (i.e., the isocyanate groups of the polyhydric isocyanate as a raw material) that (D) the polyvalent isocyanate has before the reaction may be greater than 1 or may be 1.5 or more. When [NCO] / [OH] is greater than 1, a large number of unreacted isocyanate groups are present in the hydraulic composition, which is preferable because it is possible to utilize a large amount of the reaction between the isocyanate groups and water or the polyhydric alcohol as the cement hardens.

[0034] The urethane resin may contain at least one residue selected from the group consisting of the above (C1), (C2) and (C3) components, or may contain all of the residues of the above (C1), (C2) and (C3) components. The content of the (C1) component in the raw material of the urethane resin may be 20 to 70 mass% or 30 to 60 mass% based on 100 mass% of the total amount of the polyhydric alcohol used. The content of the (C2) component in the raw material of the urethane resin may be 1 to 15 mass% or 3 to 10 mass% based on 100 mass% of the total amount of the polyhydric alcohol used. The content of the (C3) component in the raw material of the urethane resin may be 5 to 30 mass% or 10 to 25 mass% based on 100 mass% of the total amount of the polyhydric alcohol used.

[0035] [Surfactants] The surfactant may be at least one selected from the group consisting of nonionic surfactants and anionic surfactants. The content of the surfactant in the forced emulsification type urethane resin emulsion is preferably 0.1 to 5 parts by mass per 100 parts by mass of the forced emulsification type urethane resin emulsion. Examples of the surfactant include nonionic surfactants such as fatty acid esters such as sorbitan fatty acid esters, polyglycerin fatty acid esters, and sucrose fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene polyoxybutylene alkyl ethers, polyoxyethylene alkenyl ethers, polyoxyethylene polyoxypropylene alkenyl ethers, polyoxyethylene polyoxybutylene alkenyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, fatty acid alkanolamides, and Pluronic type surfactants.

[0036] Examples of the anionic surfactant that can be used include various fatty acid salts, alkylbenzenesulfonates, alkanesulfonates, alkyl sulfates, alkyl phosphates, polyoxyethylene alkyl ether sulfates, polyoxyethylene-substituted phenyl ether sulfates, polycarboxylates, etc., and examples of the counter ion include sodium, potassium, calcium, ammonium, triethanolamine, etc. Specific examples of the anionic surfactant include sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, etc.

[0037] [aggregate] The aggregate is not particularly limited, and may be fine aggregate, coarse aggregate, etc. The fine aggregate is not particularly limited, and may be silica sand, river sand, sea sand, mountain sand, crushed sand, hard blast furnace slag fine aggregate, blast furnace slag fine aggregate, copper slag fine aggregate, electric furnace oxidized slag fine aggregate, etc. The coarse aggregate is not particularly limited, and may be gravel, crushed stone, blast furnace slag coarse aggregate, electric furnace oxidized slag coarse aggregate, etc. The hydraulic composition may contain at least one of fine aggregate and coarse aggregate. In addition, the hydraulic composition may contain two or more types of fine aggregate, or may contain two or more types of coarse aggregate. As defined in JIS A 0203:2014 "Terminology of Concrete", fine aggregate is aggregate that passes through a 10 mm mesh sieve in its entirety and passes through a 5 mm mesh sieve by 85% or more by mass, and coarse aggregate is aggregate that remains on a 5 mm mesh sieve by 85% or more by mass.

[0038] When the aggregate contains only fine aggregate, the content of the aggregate in the hydraulic composition is preferably 50 to 500 parts by mass, more preferably 100 to 400 parts by mass, and further preferably 150 to 350 parts by mass, per 100 parts by mass of cement.

[0039] [Thickener] Examples of the thickener include cellulose-based, protein-based, latex-based, modified acrylic-based, and water-soluble polymer-based thickeners. The thickener is preferably a modified acrylic-based or cellulose-based thickener. The thickener may be used alone or in combination of two or more. The content of the thickener in the hydraulic composition may be 0.001 to 1 part by mass, or 0.01 to 0.5 parts by mass, relative to 100 parts by mass of cement.

[0040] [Antifoaming agent] The defoaming agent may be, for example, a synthetic substance such as a mineral oil-based, silicone-based, alcohol-based, or polyether-based substance, or a natural substance derived from a plant, and is preferably a defoaming agent suitable for defoaming urethane from the viewpoint of defoaming in urethane resin and urethane dispersion slurry. Specific examples include acrylic polymers, vinyl ether-based polymers, butadiene polymers, olefin polymers, dimethyl silicone, modified silicones, particularly polyether-modified silicones, fluorine-modified silicones, alkyl-modified silicones, alkyl-aralkyl-modified silicones, higher aliphatic ester-modified silicones, higher fatty acid amide-modified silicones, phenyl-modified silicones, mineral oils, nonionic surfactants, anionic surfactants, cationic surfactants, acetylene diols, hydrophobic silica, waxes, metal soaps such as aluminum stearate, polyoxyalkylene glycols, and any combination thereof. The content of the defoaming agent in the hydraulic composition may be 0.01 to 2.5 parts by mass, or 0.015 to 2.0 parts by mass, per 100 parts by mass of cement.

[0041] [Water reducing agent] Examples of water-reducing agents include naphthalene sulfonate-formaldehyde condensate-based water-reducing agents, melamine sulfonate-formaldehyde condensate-based water-reducing agents, polycarboxylic acid-based water-reducing agents, lignin sulfonic acid-based water-reducing agents, polystyrene sulfonic acid-based water-reducing agents, phenol formaldehyde condensate-based water-reducing agents, and aniline sulfonic acid-based water-reducing agents. The water-reducing agent has surfactant properties and acts as an emulsifier that stably disperses the dispersion obtained by mixing water and a compound having a hydroxyl group. Furthermore, the water-reducing agent can improve the fluidity of the hydraulic composition and improve the workability and workability. In addition, by improving the fluidity, the mixability of the hydraulic composition can be improved and the uniformity of the hydraulic composition can be improved. The content of the water-reducing agent in the hydraulic composition may be 0.02 parts by mass or more relative to 100 parts by mass of cement. From the viewpoint of further improving the fluidity, the content of the water reducing agent in the hydraulic composition may be 0.04 parts by mass or more, or 0.05 parts by mass or more, per 100 parts by mass of cement. The content of the water reducing agent in the hydraulic composition may be 0.5 parts by mass or less, per 100 parts by mass of cement.

[0042] The flow value of the hydraulic composition may be 150 to 300 mm. From the viewpoint of further improving the fluidity of the hydraulic composition and further improving the uniformity and workability of the hydraulic composition, the lower limit of the flow value may be 180 mm, 190 mm, or 200 mm. From the same viewpoint, the upper limit of the flow value may be 280 mm or 260 mm. The "flow value" in the present disclosure can be measured based on NEXCO Test Method 313 "Test Method for Air Mortar and Air Milk". The flow cone used for the measurement may have an inner diameter of 80 mm and a height of 80 mm, for example.

[0043] The air content of the hydraulic composition may be 7.0% or less. The air content can be measured based on JIS A 1171 "Test method for polymer cement mortar - Air content test". The air content may be 0.1% or more.

[0044] [Other ingredients] The hydraulic composition may contain other components (additives) such as gypsum, inorganic fine powder, ink, pigment, dispersant, setting regulator, expansion agent, shrinkage reducing agent, and the like.

[0045] The hydraulic composition of this embodiment may be a concrete composition or a mortar composition, and is preferably a mortar composition.

[0046] <Method for producing hydraulic composition> A method for producing a hydraulic composition according to one embodiment includes a step of obtaining a hydraulic composition by mixing (A) cement with (B) a forced emulsification type urethane resin emulsion in which a urethane resin obtained by a polymerization reaction of (C) a polyhydric alcohol and (D) a polyhydric isocyanate is dispersed in water, and the content of the urethane resin in the hydraulic composition satisfies at least one selected from the group consisting of the following conditions (1) and (2): (1) The above (A) is 25 parts by mass or less per 100 parts by mass of cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition.

[0047] The process for obtaining a hydraulic composition may include a process (step 2) for obtaining a forced emulsification type urethane resin emulsion (B) in which a urethane resin formed by a polymerization reaction of a polyhydric alcohol (C) and a polyisocyanate (D) is dispersed in water, and a process (step 3) for obtaining a hydraulic composition by mixing the forced emulsification type urethane resin emulsion (B) with the cement (A). In addition, the process may include a process (step 1) for obtaining a urethane resin (e.g., a partial polymer containing a urethane compound) by heating a mixture of the polyhydric alcohol (C) and the polyisocyanate (D) prior to the process 2. The raw materials used in producing the hydraulic composition may be those mentioned above.

[0048] In step 1, a mixture of (C) polyhydric alcohol and (D) polyisocyanate is heated to obtain a urethane resin. The conditions for obtaining the urethane resin are not particularly limited as long as the hydroxyl group of (C) polyhydric alcohol and the isocyanate group of (D) polyisocyanate react with each other, but it is preferable to perform the heating at 80 to 150°C, for example. The heating time is preferably 1 to 5 hours. Step 1 may be performed under an inert atmosphere such as nitrogen or argon.

[0049] In step 2, the urethane resin obtained in step 1 may be dispersed in water to obtain a forced emulsification type urethane resin emulsion (B). For example, a urethane resin, a surfactant, and water are mixed and mechanically stirred to obtain a forced emulsification type urethane resin emulsion (B). In the manufacturing method of this embodiment, since the urethane resin is made into a forced emulsification type urethane resin emulsion (B) in step 2, it is easy to mix with other components such as cement and has excellent workability. Note that the forced emulsification type urethane resin emulsion (B) is not limited to being prepared as described above, and may be prepared by purchasing a commercially available product and diluting it with water to obtain an arbitrary solid content concentration of the urethane resin.

[0050] The solid content concentration of the urethane resin in the (B) forced emulsification type urethane resin emulsion obtained in step 2 may be 5% by mass or more, or may be 7% by mass or more. When the solid content concentration of the urethane resin is in this range, the homogeneity of the urethane resin in the emulsion can be improved. In addition, the solid content concentration of the urethane resin may be 65% by mass or less, or may be 60% by mass or less. When the solid content concentration of the urethane resin is in this range, aggregation of the urethane resin in the emulsion can be suppressed.

[0051] In step 3, the (B) forced emulsification type urethane resin emulsion obtained in step 2 is mixed with the (A) cement so as to satisfy the condition (1) or (2). Mixing may be performed using a Hobart mixer or the like. Other additives may be blended into the cement together with the partial polymer, or may be blended after the (B) forced emulsification type urethane resin emulsion and the (A) cement are mixed. In addition, aggregate and additional water may also be blended into the (A) cement together with the (B) forced emulsification type urethane resin emulsion, or may be blended after the (B) forced emulsification type urethane resin emulsion and the (A) cement are mixed.

[0052] In step 3, 0.02 parts by mass or more of a water-reducing agent may be added relative to 100 parts by mass of (A) cement. From the viewpoint of further improving fluidity, the content of the water-reducing agent in the hydraulic composition may be 0.04 parts by mass or more, or 0.05 parts by mass or more, relative to 100 parts by mass of (A) cement. The content of the water-reducing agent may be 0.5 parts by mass or less relative to 100 parts by mass of (A) cement.

[0053] The hydraulic composition obtained by the above-mentioned production method may have a flow value of 150 to 300 mm. From the viewpoint of further improving the fluidity of the hydraulic composition and further improving the uniformity and workability of the hydraulic composition, the lower limit of the flow value may be 180 mm, 190 mm, or 200 mm. From the same viewpoint, the upper limit of the flow value may be 280 mm, or 260 mm.

[0054] <Method of manufacturing the cured product> The manufacturing method of the hardened product (cement-based hardened product) is not particularly limited, and may include a step of molding the hydraulic composition to obtain a molded body (step 4), and a step of curing the molded body (step 5). The molding method is not particularly limited, and the hydraulic composition may be poured into a mold (metal, plastic, etc.). Deaeration may be performed using a vibrator as necessary. The hydraulic composition is placed in the mold and left to stand for, for example, about 1 to 5 days to obtain a molded body. When a core material such as reinforcing bars or steel frames is used, the core material may be placed in the mold before the hydraulic composition is poured in.

[0055] In step 5, the molded body obtained in step 4 is cured. The molded body may be demolded before curing. The curing method is not particularly limited, and may be any curing method such as sealed curing or underwater curing. Curing is performed until the hydraulic composition solidifies.

[0056] The hardened product of the present embodiment has high compressive strength and low water absorption, and therefore can be used for various applications such as building materials, wave dissipating blocks, etc. In particular, it is useful as a material for a part of a bridge or viaduct that comes into contact with water or comes into frequent contact with water during use, such as a shoe seat material for a support part of the bridge or viaduct, or a wave dissipating block.

[0057] The compressive strength of the hardened material after 28 days is 35N / mm 2 It may be more than 40N / mm 2 It may be more than 50N / mm 2 If the compressive strength of the cured product is in this range, a cured product having sufficiently high strength can be obtained. Such a cured product is suitable as a covering material for architectural and civil engineering structures. In addition, the compressive strength of the cured product at 28 days is 90 N / mm 2 It may be less than 80N / mm 2 The compressive strength of the hardened product can be measured based on JSCE-G-505 "Test method for compressive strength of mortar or cement paste using cylindrical specimen (draft)".

[0058] The water absorption of the hardened product can be evaluated by measuring the water absorption height of the hardened product based on the method described in JSCE-G 582-2018 "Test method for water penetration rate coefficient in concrete subjected to short-term water exposure". The water absorption height of the hardened product may be 15 mm or less, or 12 mm or less. When the water absorption height of the hardened product is in this range, a hardened product with sufficiently low water absorption can be obtained. In addition, the water absorption height may be 0 mm or more, or 5 mm or more. A hardened product with a water absorption height of 5 mm or more has a sufficiently high flow value of the hydraulic composition, and is excellent in uniformity and workability of the hydraulic composition. Such a hardened product is suitable as a coating material for architectural and civil engineering structures.

[0059] Although several embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments.

[0060] The present disclosure includes several embodiments below. [1] (A) a cement; and (B) a forced emulsification type urethane resin emulsion containing a urethane resin, The hydraulic composition, wherein the content of the urethane resin satisfies at least one selected from the group consisting of the following conditions (1) and (2): (1) The (A) cement is contained in an amount of 25 parts by mass or less per 100 parts by mass of the cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition. [2] The hydraulic composition according to [1], wherein the (B) forcibly emulsified urethane resin emulsion contains a surfactant. [3] The hydraulic composition according to [2], wherein the surfactant includes at least one selected from the group consisting of nonionic surfactants and anionic surfactants. [4] The hydraulic composition according to any one of [1] to [3], wherein the urethane resin is a polymer of (C) a polyhydric alcohol and (D) a polyhydric isocyanate. [5] The hydraulic composition according to [4], wherein the (C) polyhydric alcohol contains at least one bond selected from the group consisting of an ether bond and an ester bond. [6] The hydraulic composition according to [4], wherein the (D) polyisocyanate includes at least one selected from the group consisting of aromatic polyisocyanates and aliphatic polyisocyanates. [7] The hydraulic composition according to any one of [1] to [6], which contains aggregate. [8] The hydraulic composition according to any one of [1] to [7], which has a flow value of 150 to 300 mm. [9] The hydraulic composition according to any one of [1] to [8], comprising 0.02 to 0.5 parts by mass of a water-reducing agent per 100 parts by mass of the (A) cement.

[10] A hardened product which is a hardened product of the hydraulic composition according to any one of the above [1] to [9].

[11] A method for producing a hydraulic composition comprising the steps of: (A) mixing cement with (B) a forced emulsification type urethane resin emulsion in which a urethane resin obtained by a polymerization reaction of (C) a polyhydric alcohol and (D) a polyhydric isocyanate is dispersed in water; A method for producing a hydraulic composition, wherein the content of the urethane resin in the hydraulic composition satisfies at least one selected from the group consisting of the following conditions (1) and (2): (1) The (A) cement is contained in an amount of 25 parts by mass or less per 100 parts by mass of the cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition.

[12] The method for producing a hydraulic composition according to

[11] , wherein the hydraulic composition has a flow value of 150 to 300 mm.

[13] The method for producing a hydraulic composition according to

[11] or

[12] , wherein in the step, 0.02 to 0.5 parts by mass of a water reducing agent is added to 100 parts by mass of the (A) cement to obtain the hydraulic composition. EXAMPLES

[0061] The present disclosure will be described in more detail below with reference to examples and comparative examples. Note that the present disclosure is not limited to the following examples.

[0062] Example 1 <Preparation of urethane resin> Using a balance, three types of polyhydric alcohols were weighed and charged into the separable flask: 314.89 g of Actocol ED28 (component (C1), manufactured by Mitsui Chemicals SKC Polyurethanes Inc.), 41.63 g of dipropylene glycol (component (C2)), and 102.94 g of EXCENOL 5030 (component (C3), manufactured by AGC Inc.).

[0063] The polyhydric alcohol was mixed while supplying N2 gas.

[0064] 138.55 g of Coronate T-100 (polyisocyanate, manufactured by Tosoh Corporation) was weighed out and placed in the separable flask body. The mixture was heated at 100° C. for 3 hours while stirring to prepare a urethane resin.

[0065] The degree of reaction of the urethane resin was evaluated according to JIS K 7301, and the end point was determined as the time when the content of isocyanate groups became approximately equal to the content when all of the hydroxyl groups of the polyhydric alcohol reacted.

[0066] <Preparation of forced emulsification type urethane resin emulsion> 4 g of a surfactant (sodium lauryl sulfate) was added to 1000 g of water, followed by 100 g of urethane resin. The mixture was mechanically stirred at a stirring speed of 600 rpm for 3 hours using a homogenizer (product name: Homo Disper, manufactured by Primix Corporation) to obtain a forced emulsification type urethane resin emulsion.

[0067] <Preparation of hydraulic composition> Each component was mixed in the amount shown in Example 1 of Table 2. Specifically, first, cement, silica sand, and additives (thickener, water reducer, etc.) were weighed, put into a Hobart mixer, and mixed for 1 minute to obtain a mixture. Next, the forced emulsification type urethane resin emulsion prepared as described above was put into the mixture and mixed by the Hobart mixer. In order to prevent poor mixing, the Hobart mixer was stopped after the start of mixing (for example, about 1 minute), and materials attached to the stirring blade and the kettle were removed. Mixing was started again, and mixing was performed for 2 minutes to obtain a hydraulic composition. The air content of the prepared hydraulic composition was measured based on JIS A 1171 "Test method for polymer cement mortar - Air content test".

[0068] The symbols in Tables 2 and 3 have the following meanings: C: Cement content (g) P: Amount of urethane resin (g) S: Amount of fine aggregate (silica sand) (g) Su: Amount of surfactant (g) W: Amount of water (g) W1: The amount of water (W) added when diluting the commercially available urethane resin emulsions of Examples 8 to 14 and Comparative Example 2 (g) W2: Of the blended amount of water (W), the amount of water (g) already contained in the commercially available urethane resin emulsions of Examples 8 to 14 and Comparative Example 2 A: Amount of water-reducing agent (g) V: Amount of thickener (g) D1: Amount of defoamer (g) C / S: Mass ratio of cement to aggregate (cement / aggregate) P / C: Mass ratio of urethane resin to cement (urethane resin / cement) P / (P+W): Mass ratio of urethane resin to forced emulsification type urethane resin emulsion (P+W) / Total: Mass ratio of forced emulsification type urethane resin emulsion to hydraulic composition W / P: Mass ratio of water to urethane resin (water / urethane resin)

[0069] The following cement, water reducing agent and defoaming agent were used. Cement: High-early-strength Portland cement (Blaine specific surface area 4500 cm 2 / g, manufactured by UBE Mitsubishi Cement Corporation) Water reducing agent: Melflux AP 101F (product name, manufactured by SKW East Asia Co., Ltd., polycarboxylic acid type) or Mighty 21P (product name, manufactured by Kao Corporation, polycarboxylic acid type) Defoaming agent: Adekanate B115 (trade name, manufactured by ADEKA Corporation), Adekanate B1046 (trade name, manufactured by ADEKA Corporation), or BYK1794 (trade name, manufactured by BYK-Chemie Japan Co., Ltd.) Thickener: Marporose MX30000 (product name, manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.)

[0070] Example 2 4 g of a surfactant (sodium lauryl sulfate) was added to 1000 g of water, followed by adding 100 g of urethane resin, and a forced emulsification type urethane resin emulsion was prepared by stirring in the same manner as in Example 1. Next, the components were mixed in the amounts shown in Example 2 in Table 2 to prepare a hydraulic composition. Mixing was performed in the same manner as in Example 1, and the air content was measured in the same manner as in Example 1.

[0071] (Examples 3 to 7) The urethane resin in Table 2 was dispersed in water mixed with a surfactant in the same table. Specifically, the surfactant (sodium lauryl sulfate) was added to a specified amount of water, followed by the urethane resin, and the mixture was stirred for 1 to 3 hours to obtain a forced emulsification type urethane resin emulsion. Next, the components were mixed in the amounts shown in Examples 3 to 7 in Table 2 to prepare a hydraulic composition. Mixing was performed in the same manner as in Example 1.

[0072] (Examples 8 to 14) <Preparation of commercially available urethane resin emulsion> Commercially available urethane resin emulsions with different product names were purchased from DIC Corporation and NICCA Chemical Co., Ltd. The solid content concentration of the urethane resin, the type of polyol in the urethane resin, the type of isocyanate, and the ionicity of the surfactant for each product name of the urethane resin emulsion purchased from DIC Corporation are shown in Table 1. The urethane resin emulsion purchased from NICCA Chemical Co., Ltd. had the product name AP-12 and a urethane resin solid content concentration of 40.0 mass%.

[0073] [Table 1]

[0074] <Preparation of forced emulsification type urethane resin emulsion> A commercially available urethane resin emulsion was diluted with water to obtain the forced emulsification type urethane resin emulsion used in Examples 8 to 14. The amount of water (g) added for dilution is as shown in the W1 section of Table 2. Using the obtained forced emulsification type urethane resin emulsion, hydraulic compositions were prepared in the amounts shown in Examples 8 to 14 of Table 2. Since the amount of surfactant contained in the commercially available product is not clear, the amount of surfactant in Examples 8 to 14 of Table 2 is marked "unknown." Mixing was performed in the same manner as in Example 1.

[0075] Comparative Example 1 A hydraulic composition was prepared by replacing the urethane resin in Example 1 with water and mixing each component in the amounts shown in Table 2. That is, Comparative Example 1 is a hydraulic composition that does not contain a urethane resin. Mixing was performed in the same manner as in Example 1.

[0076] Comparative Example 2 A hydraulic composition was prepared using a commercially available self-emulsifying urethane resin emulsion "MELUSI6070" (product name, manufactured by Toyo Polymer Co., Ltd.) in the amounts shown in Comparative Example 2 in Table 2. Mixing was performed in the same manner as in Example 1.

[0077] The blending amount of the urethane resin shown in Tables 2 and 3 is the blending amount as a solid content, not as an emulsion. The blending amount of water (W) is the amount of water contained in the hydraulic composition, and all of the water was blended with other components as an emulsion.

[0078] <Evaluation of compatibility> The flow values ​​of the hydraulic compositions of Examples 1, 2, 8 to 14 and Comparative Example 1 were measured. The flow values ​​were measured based on NEXCO Test Method 313 "Test Method for Air Mortar and Air Milk". The flow cone used had an inner diameter of 80 mm and a height of 80 mm. The results are shown in Table 3.

[0079] <Preparation of specimen> The prepared hydraulic compositions of Examples 1 to 14 and Comparative Examples 1 and 2 were each placed in a mold. After one day, the molded bodies were removed from the molds to obtain molded bodies. The molded bodies were submerged in water and cured for 28 days (underwater curing) to obtain test specimens.

[0080] <Evaluation of dispersibility of urethane resin> The dispersibility of the urethane resin in the hydraulic composition was evaluated by visually inspecting the cross section of the test specimen after 28 days. The hydraulic composition in which no lumps of urethane resin were visually observed and the urethane resin was dispersed in the hydraulic composition was rated as "A." In the hydraulic composition of Comparative Example 2, white lumps of urethane resin were observed on the cross section of the test specimen after 28 days, so the dispersibility of the urethane resin was rated as "B." The evaluation results of mixability are shown in Table 3.

[0081] <Method of measuring compressive strength> (Compressive strength) A compressive strength test was carried out on each of the specimens of Examples 1 to 14 and Comparative Example 1 at a material age of 28 days. The compressive strength test method was in accordance with the method described in JSCE-G-505 "Compressive strength test method (draft) for mortar or cement paste using cylindrical specimens." The compressive strength test results are shown in Table 3.

[0082] <Evaluation of water absorbency> A water absorption test was carried out on each specimen of Examples 1 to 14 and Comparative Example 1. The water absorption test was carried out according to the method described in "Test method for water penetration rate coefficient in concrete subjected to short-term water exposure" in JSCE-G 582-2018. The test results of water absorption height are shown in Table 3.

[0083] [Table 2]

[0084] [Table 3]

[0085] As can be seen from Table 3, Examples 1 to 14 had better water absorbency than Comparative Example 1. Furthermore, Examples 1, 2, and 8 to 14 had improved flow values ​​and showed higher mixability than Comparative Example 1. [Industrial Applicability]

[0086] According to the present disclosure, it is possible to provide a set product having sufficiently high compressive strength and low water absorption, as well as a hydraulic composition capable of obtaining such a set product, and a method for producing the same.

Claims

1. (A) cement; and (B) a forced emulsification type urethane resin emulsion containing a urethane resin, The hydraulic composition, wherein the content of the urethane resin satisfies at least one selected from the group consisting of the following conditions (1) and (2): (1) The (A) cement is contained in an amount of 25 parts by mass or less per 100 parts by mass of the cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition.

2. The hydraulic composition according to claim 1, wherein the (B) forcibly emulsified urethane resin emulsion contains a surfactant.

3. The hydraulic composition according to claim 2, wherein the surfactant comprises at least one selected from the group consisting of nonionic surfactants and anionic surfactants.

4. The hydraulic composition according to any one of claims 1 to 3, wherein the urethane resin is a polymer of (C) a polyhydric alcohol and (D) a polyhydric isocyanate.

5. The hydraulic composition according to claim 4, wherein the polyhydric alcohol (C) contains at least one bond selected from the group consisting of an ether bond and an ester bond.

6. The hydraulic composition according to claim 4, wherein the polyisocyanate (D) includes at least one selected from the group consisting of aromatic polyisocyanates and aliphatic polyisocyanates.

7. The hydraulic composition according to any one of claims 1 to 3, which contains aggregate.

8. The hydraulic composition according to any one of claims 1 to 3, having a flow value of 150 to 300 mm.

9. The hydraulic composition according to any one of claims 1 to 3, comprising 0.02 to 0.5 parts by mass of a water reducing agent per 100 parts by mass of the (A) cement.

10. A hardened product which is a hardened product of the hydraulic composition according to any one of claims 1 to 3.

11. The method includes a step of obtaining a hydraulic composition by mixing (A) cement with (B) a forced emulsification type urethane resin emulsion in which a urethane resin obtained by a polymerization reaction of (C) a polyhydric alcohol and (D) a polyhydric isocyanate is dispersed in water, A method for producing a hydraulic composition, wherein the content of the urethane resin in the hydraulic composition satisfies at least one selected from the group consisting of the following conditions (1) and (2): (1) The (A) cement is contained in an amount of 25 parts by mass or less per 100 parts by mass of the cement. (2) It is 7% by mass or less relative to 100% by mass of the total amount of the hydraulic composition.

12. The method for producing a hydraulic composition according to claim 11, wherein the hydraulic composition has a flow value of 150 to 300 mm.

13. The method for producing a hydraulic composition according to claim 11 or 12, wherein in the step, 0.02 to 0.5 parts by mass of a water reducing agent is added to 100 parts by mass of the (A) cement to obtain the hydraulic composition.

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