Admixture for hydraulic composition

Abstract

To provide an admixture for hydraulic composition that exhibits excellent fluidity after vibration.SOLUTION: The admixture for hydraulic composition comprises the following components (A), (B) and (C): component (A) is a lignin derivative, component (B)is a copolymer having specific constituent unit, and component (C) is an oxycarboxylate.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an admixture for hydraulic compositions and a hydraulic composition containing the admixture for hydraulic compositions. [Background technology]

[0002] Lignin is a natural polymeric substance found in trees, accounting for approximately 30% of wood. Lignin is found in large amounts in waste liquor from kraft pulp production (kraft pulp waste liquor) and waste liquor from sulfite pulp production (sulfite pulp waste liquor). From the perspective of reducing environmental impact in recent years, lignin has been attracting attention as one of the biomass resources.

[0003] Kraft lignin contained in kraft pulp waste liquor and lignosulfonic acid contained in sulfite pulp waste liquor each have different physical properties and are used for various purposes. In addition, lignin derivatives obtained by sulfomethylating kraft lignin with sulfite and formaldehyde, lignin derivatives obtained by partially desulfonating lignosulfonic acid or a salt of lignosulfonic acid, and lignin purified products obtained by ultrafiltration are widely used as lignin-based dispersants in a wide range of industrial fields, such as dyes, cement, inorganic pigments, organic pigments, gypsum, coal-water slurries, agricultural chemicals, and ceramics.

[0004] As a dispersant for hydraulic compositions such as cement, Patent Documents 1 and 2 disclose cement admixtures containing a lignin derivative containing lignin sulfonic acid or a salt thereof, a copolymer of an acrylic acid and / or a methacrylic acid derivative, and oxycarboxylic acids or sugars.

[0005] Patent Document 3 discloses a dispersant for hydraulic compositions, which contains Component A, which is water having an oxidation-reduction potential of 0 mV or more at 25° C.; Component B, which is at least one selected from (a) a polycarboxylic acid-based dispersant and (b) a lignin sulfonic acid-based dispersant; and Component C, which is an antiseptic component. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2012-180254 A [Patent Document 2] JP 2011-57459 A [Patent Document 3] Patent Publication No. 2022-37656 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, in the environment surrounding ready-mix concrete, in addition to the deterioration of the quality of ready-mix concrete due to the deterioration of aggregate quality in terms of materials, in terms of construction, the workability is being reduced due to overcrowding of reinforcement bars, and the number of skilled workers is also decreasing. Therefore, there is a demand for admixtures for hydraulic compositions with excellent workability. In particular, in the field of ready mixed concrete, where ready mixed concrete is transported to a site by an agitator truck, the ready mixed concrete is pumped by a pump truck, and then filled into a formwork with dense reinforcement by vibrating it using a rod-shaped vibrator, etc. Therefore, there is a demand for an admixture for hydraulic compositions that can provide a hydraulic composition with excellent fluidity when vibrated more than ever before. Therefore, the present inventors considered that by providing an admixture for hydraulic compositions having excellent fluidity when vibrated by a rod-shaped vibrator or the like at a construction site, it would be possible to reduce or eliminate construction defects and reduce the number of workers required, leading to improved productivity and easier handling at the site. Patent Document 1 discloses a cement admixture having excellent cement dispersing properties and slump retention properties, capable of lowering the viscosity of the cement composition, improving workability, and reducing the environmental load, and a cement composition using the same, but does not mention anything about fluidity during vibration. Patent Document 2 presents a cement admixture having excellent cement dispersing properties and capable of shortening the solidification time of cement and cement compositions, but does not mention anything about fluidity during vibration.

[0008] The present invention provides an admixture for hydraulic compositions, which contains a lignin derivative, a copolymer of an acrylic acid derivative, and an oxycarboxylic acid, and which has excellent fluidity when shaken on site. [Means for solving the problem]

[0009] The present invention relates to an admixture for a hydraulic composition, the admixture for a hydraulic composition comprising the following components (A), (B) and (C): (A) Component: Lignin derivative. (B) Component: General formula (b1) [ka] [In the formula, M 1b R represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 1b , R 2b and R 3b are the same or different and each represents a hydrogen atom, a methyl group, or a group represented by the general formula -(CH 2 ) r COOM 2b (2b) [wherein r represents 0, 1 or 2; M 2b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) r COOM 2b (2b) is -COOM 1b or other -(CH 2 ) r COOM 2b may be bonded to form an acid anhydride bond -C(=O)-OC(=O)-, in which case, M 1b , M 2b does not exist.] A structural unit (B1) represented by the formula: General formula (b2) [ka] [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q1 represents 0, 1 or 2, p1 represents 0 or 1, and n1 represents the average number of moles of AO added, which is a number of 5 to 150. 4b , R 5b and R 6b are the same or different and each represents a hydrogen atom, a methyl group, a group of the general formula -(CH 2 ) s COOM 3b (3b) [wherein s represents 0, 1 or 2; M 3b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) q2 (CO) p2 O(AO) n2 R 8b (4) [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q2 represents 0, 1 or 2, p2 represents 0 or 1, n2 represents the average number of moles of AO added and is a number of 5 to 150, and R 8b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. A structural unit (B2) represented by the formula: and optionally having the general formula (b3) [ka] [In the formula, R 9b represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom. A copolymer having a structural unit (B3) represented by the following formula: (C) Hydroxycarboxylate. Effect of the Invention

[0010] According to the present invention, it is possible to provide an admixture for hydraulic compositions having excellent fluidity when shaken. Also, it is possible to provide a hydraulic composition containing the admixture for hydraulic compositions of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The admixture for hydraulic compositions of the present invention contains the following components (A), (B) and (C). (A) Component: Lignin derivative. (B) Component: General formula (b1) [ka] [In the formula, M 1b R represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 1b , R 2b and R 3b are the same or different and each represents a hydrogen atom, a methyl group, or a group represented by the general formula -(CH 2 ) r COOM 2b (2b) [wherein r represents 0, 1 or 2; M 2b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) r COOM 2b (2b) is -COOM 1b or other -(CH 2 ) r COOM 2b may be bonded to form an acid anhydride bond -C(=O)-OC(=O)-, in which case, M 1b , M 2b does not exist.] A structural unit (B1) represented by the formula: General formula (b2) [ka] [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q1 represents 0, 1 or 2, p1 represents 0 or 1, and n1 represents the average number of moles of AO added, which is a number of 5 to 150. 4b , R 5b and R 6b are the same or different and each represents a hydrogen atom, a methyl group, a group of the general formula -(CH 2 ) s COOM 3b (3b) [wherein s represents 0, 1 or 2; M 3b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) q2 (CO) p2 O(AO) n2 R 8b (4) [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q2 represents 0, 1 or 2, p2 represents 0 or 1, n2 represents the average number of moles of AO added and is a number of 5 to 150, and R 8b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. A structural unit (B2) represented by the formula: and optionally having the general formula (b3) [ka] [In the formula, R 9b represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom. A copolymer having a structural unit (B3) represented by the following formula: (C) Hydroxycarboxylate.

[0012] The admixture for hydraulic compositions of the present invention contains lignin sulfonic acid or a salt thereof as component (A). Examples of counter cations of the salts include alkali metal ions such as lithium, sodium, potassium, etc., alkaline earth metal ions such as magnesium, calcium, etc., and organic cations such as quaternary ammonium ions. In terms of availability, salts whose counter cation is an alkali metal ion are preferred, and among these, salts whose counter cation is a sodium ion are preferred.

[0013] The admixture for hydraulic compositions of the present invention contains a lignin derivative as component (A). Examples of the lignin derivative include pulp lignins such as kraft lignin, soda lignin, and lignosulfonic acid, lignophenol, phenolized lignin, and modified lignin. Kraft lignin is a lignin derivative whose molecular structure is modified after carbohydrates such as cellulose are extracted from wood in the paper and pulp industry. Lignosulfonic acid is a polymer electrolyte with functional groups such as sulfonic acid, carboxyl acid, and phenolic hydroxyl acid, and there are no particular limitations on its molecular weight or manufacturing method. Lignophenol can be obtained, for example, by treating lignin in lignocellulosic materials with a phenol derivative. There is no particular restriction on the structure. Phenolized lignin is lignin in a stabilized state in which a phenol derivative is chemically bonded to the molecular chains of lignin when lignin and cellulose are separated by treating a plant material with an acid. Modified lignin is lignin with polyethylene glycol chains attached to the backbone of the lignin. Of these, lignosulfonic acid and / or a salt thereof is preferred.

[0014] It is difficult to uniformly specify the chemical structure of lignosulfonic acid and / or its salts by a general formula or the like, because lignin, which is the skeleton of lignosulfonic acid, has a very complicated molecular structure.

[0015] The lignin sulfonic acid and / or its salt may be prepared or may be a commercially available product. Here, the preparation method of the lignin derivative is exemplified below. However, the lignin sulfonic acid and / or its salt is not limited to those prepared by the preparation method described below.

[0016] Examples of methods for preparing lignosulfonic acid and / or a salt thereof include a method in which a lignocellulosic raw material is subjected to a sulfite treatment, preferably a method in which a lignocellulosic raw material is subjected to a sulfite cooking treatment.

[0017] The lignocellulose raw material is not particularly limited as long as it contains lignocellulose in the structure, and examples thereof include pulp raw materials such as wood and non-wood. Examples of wood include coniferous trees such as Yezo spruce, red pine, cedar, and cypress, and broad-leaved trees such as white birch and beech. The age and location of the wood are not important. Therefore, wood harvested from trees of different ages or from different locations of a tree may be used in combination. Non-wood materials include, for example, bamboo, kenaf, reed, and rice. The lignocellulosic raw material may be one of these materials, or two or more of them may be used in combination.

[0018] The sulfite treatment can be carried out by contacting at least one of sulfurous acid and a sulfite salt with a lignocellulosic raw material to obtain an intermediate product. The conditions for the sulfite treatment are not particularly limited as long as they allow introduction of a sulfonic acid (salt) group to the α-carbon atom of the side chain of lignin contained in the lignocellulosic raw material.

[0019] The sulfite treatment is preferably carried out by a sulfite cooking method, which allows more quantitative sulfonation of the lignin in the lignocellulosic raw material. The sulfite cooking method is a method in which lignocellulosic raw materials are reacted at high temperatures in a solution of at least one of sulfurous acid and a sulfite salt (e.g., an aqueous solution: cooking liquor). This method has been established and is being used industrially as a method for producing sulfite pulp. Therefore, by carrying out the sulfite treatment by the sulfite cooking method, it is possible to improve the economic efficiency and ease of implementation.

[0020] When sulfite cooking is carried out, examples of the sulfite salt include magnesium salts, calcium salts, sodium salts and ammonium salts.

[0021] There is no limitation on the equipment used in the sulfite treatment, and for example, generally known dissolving pulp manufacturing equipment can be used.

[0022] The intermediate product may be separated from the solution of at least one of sulfurous acid and sulfite salt according to a conventional method, for example, a method for separating the sulfurous acid pulping wastewater after sulfurous acid pulping.

[0023] Next, the intermediate composition is washed and dehydrated to obtain a sulfite-treated product. By washing and dehydrating, components contained in the intermediate composition that cannot be completely removed by the sulfite treatment can be removed.

[0024] The washing may be carried out in the same manner as the washing of unbleached sulfite pulp obtained by the sulfite cooking method. The washing may be a single-stage washing or a multi-stage washing. By carrying out multi-stage washing, the washing can be carried out sufficiently. When carrying out multi-stage washing, dehydration may be carried out each time, or may be carried out only for some of the times. Washing is usually performed using a washing machine. The washing machine used for washing is not particularly limited. For example, a displacement washing type washing machine and a dilution dehydration washing type washing machine can be mentioned.

[0025] The dehydration can be carried out under ordinary conditions, for example, in the same manner as in the dehydration of unbleached sulfite pulp after washing obtained in the sulfite cooking method. Dehydration is usually performed using a dehydrator. The type of dehydrator used for dehydration is not particularly limited. For example, a drum-type squeeze dehydrator, a rotary press, or a continuous squeeze dehydrator may be used.

[0026] The sulfite-treated product is then washed and dehydrated, and separated and purified to obtain the desired lignin derivative. Examples of the separation and purification include an alkaline oxidation treatment step and an ultrafiltration treatment step.

[0027] When the alkaline oxidation treatment is carried out, after the sulfite-treated product is subjected to the alkaline oxidation treatment, insoluble matters can be centrifuged and recovered as a supernatant.

[0028] The alkaline oxidation treatment can be carried out by placing the sulfurous acid-treated product under alkaline conditions. Placing the product under alkaline conditions usually means placing the product in an aqueous solution having a pH value of 8 or more, preferably a pH value of 9 or more. The upper limit of the pH value is usually 14.

[0029] In the alkaline oxidation treatment, an alkaline substance is usually brought into contact with the sulfite treatment product. The alkaline substance is not particularly limited, but examples thereof include calcium hydroxide, magnesium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, and ammonia. Among these, sodium hydroxide is preferred. The alkaline substances may be used alone or in combination of two or more.

[0030] From the viewpoint of good fluidity during vibration, the amount of component (A) added is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, and is preferably 1.00% by mass or less, more preferably 0.50% by mass or less, and even more preferably 0.3% by mass or less, based on the hydraulic powder in the hydraulic composition.

[0031] From the viewpoint of production, the component (A) contains sugars. From the viewpoint of reducing the hardening property of the cement, the content of the sugars is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less.

[0032] Next, the component (B) will be described. The component (B) is represented by the general formula (b1) [ka] [In the formula, M 1b R represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 1b , R 2b and R 3b are the same or different and each represents a hydrogen atom, a methyl group, or a group represented by the general formula -(CH 2 ) r COOM 2b (2b) [wherein r represents 0, 1 or 2; M 2b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) r COOM 2b (2b) is -COOM 1b or other -(CH 2 ) r COOM 2b may be bonded to form an acid anhydride bond -C(=O)-OC(=O)-, in which case, M 1b , M 2b does not exist.] A structural unit (B1) represented by the formula: General formula (b2) [ka] [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q1 represents 0, 1 or 2, p1 represents 0 or 1, and n1 represents the average number of moles of AO added, which is a number of 5 to 150. 4b , R 5b and R 6b are the same or different and each represents a hydrogen atom, a methyl group, a group of the general formula -(CH 2 ) s COOM3b (3b) [wherein s represents 0, 1 or 2; M 3b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) q2 (CO) p2 O(AO) n2 R 8b (4) [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q2 represents 0, 1 or 2, p2 represents 0 or 1, n2 represents the average number of moles of AO added and is a number of 5 to 150, and R 8b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. A structural unit (B2) represented by the formula: and optionally having the general formula (b3) [ka] [In the formula, R 9b represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom. and (B3) is a copolymer having a structural unit represented by the following formula:

[0033] First, the general formula (b1) will be described. M in general formula (b1) 1b represents one or more selected from a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, and an alkenyl group. From the viewpoints of convenience and availability, the counter cation is preferably an alkali metal, and more preferably sodium.

[0034] M in general formula (b1) 1bA counter cation can be introduced by copolymerizing the carboxyl group using a hydrogen atom as a raw material, and then neutralizing the carboxyl group with an alkali metal or alkaline earth metal hydroxide, ammonia, or a mono-, di-, or tri(alkyl having 2 to 8 carbon atoms, which may be substituted with a hydroxyl group)amine. Alternatively, the hydrogen atom of the carboxyl group can be exchanged for an ammonium ion and neutralized using a halide or hydroxide salt of (mono-, di-, tri-, or tetraalkyl having 2 to 8 carbon atoms, which may be substituted with a hydroxyl group). From the viewpoints of corrosion inhibition and safety, it is preferable that 20 to 95% of the hydrogen atoms of the carboxyl groups are neutralized.

[0035] R in general formula (b1) 1b , R 2b and R 3b are the same or different and each represents a hydrogen atom, a methyl group, or a group represented by the general formula -(CH 2 ) r COOM 2b (2b) [wherein r represents 0, 1 or 2; M 2b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) r COOM 2b (2b) is -COOM 1b or other -(CH 2 ) r COOM 2b may be bonded to form an acid anhydride bond -C(=O)-OC(=O)-, in which case, M 1b , M 2b does not exist.

[0036] From the viewpoint of good vibration fluidity, R of the structural unit (b1) 1b , R 2b and R 3b is preferably a hydrogen atom.

[0037] The structural unit (B1) represented by general formula (b1) can be introduced into the copolymer (B) by using a monomer represented by general formula (b1') as the raw material. [ka] [In the formula, M 1b R represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 1b , R 2b and R 3b are the same or different and each represents a hydrogen atom, a methyl group, or a group represented by the general formula -(CH 2 ) r COOM 2b (2b) [wherein r represents 0, 1 or 2; M 2b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) r COOM 2b (2b) is -COOM 1b or other -(CH 2 ) r COOM 2b may be bonded to form an acid anhydride bond -C(=O)-OC(=O)-, in which case, M 1b , M 2b does not exist.]

[0038] M in general formula (b1') 1b Examples of the cation include a hydrogen atom, alkali metals such as lithium, sodium, and potassium, and alkaline earth metals such as magnesium and calcium. From the viewpoint of good vibration fluidity, a hydrogen atom or an alkali metal is preferred. Also, R 1b , R 2b and R 3b is preferably a hydrogen atom.

[0039] Next, the general formula (b2) will be described. From the viewpoint of good fluidity during vibration, R in general formula (b2) 4b and R 5b is preferably a hydrogen atom.

[0040] R in general formula (b2) 6b Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. From the viewpoint of good vibration fluidity, a hydrogen atom and a methyl group are preferred, and a methyl group is more preferred.

[0041] In the general formula (b2), q1 is an integer of 0 or more and 2 or less. From the viewpoint of good fluidity when shaken, q1 is preferably 1 or 2, and more preferably 2.

[0042] In the general formula (b2), p1 is 0 or 1. From the viewpoint of good fluidity when shaken, p1 is preferably 0.

[0043] From the viewpoint of good fluidity when shaken, a combination in which q1 is 1 or 2 and p1 is 0 in the general formula (b2) is preferred.

[0044] AO in the general formula (b2) is an oxyalkylene group having 2 to 4 carbon atoms, and examples thereof include an oxyethylene group, an oxypropylene group, and an oxybutylene group. When AO is different in the average n1 repeating units, it may be randomly added or block added, or may contain an admixture of these. n1 in the general formula (b2) is 5 or more, preferably 10 or more, more preferably 20 or more, and 150 or less, preferably 140 or less, more preferably 100 or less, even more preferably 100 or less, and even more preferably 60 or less.

[0045] From the viewpoint of good fluidity when vibrated, it is preferable that AO contains an oxyethylene group. Also, from the viewpoint of good fluidity when vibrated, the content (mol%) of oxyethylene group in AO is preferably 70 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, and even more preferably 100 mol%. Furthermore, n1 in general formula (b2) is 5 or more, preferably 10 or more, more preferably 20 or more, and 150 or less, preferably 140 or less, more preferably 100 or less, even more preferably 100 or less, and even more preferably 60 or less.

[0046] The structural unit (B2) represented by general formula (b2) can be introduced into the copolymer (B) by using a monomer represented by general formula (b2') as the raw material. [ka] [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q1 represents 0, 1 or 2, p1 represents 0 or 1, and n1 represents the average number of moles of AO added, which is a number of 5 to 150. 4b , R 5b and R 6b are the same or different and each represents a hydrogen atom, a methyl group, a group of the general formula -(CH 2 ) s COOM 3b (3b) [wherein s represents 0, 1 or 2; M 3b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. 2 ) q2 (CO) p2 O(AO) n2 R 8b (4) [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q2 represents 0, 1 or 2, p2 represents 0 or 1, n2 represents the average number of moles of AO added and is a number of 5 to 150, and R 8b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0047] From the viewpoint of good fluidity during vibration, R in general formula (b2') 4b and R 5b is preferably a hydrogen atom.

[0048] R in general formula (b2') 6b Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. From the viewpoint of good vibration fluidity, a hydrogen atom and a methyl group are preferred, and a methyl group is more preferred.

[0049] In the general formula (b2′), q1 is an integer of 0 or more and 2 or less. From the viewpoint of good fluidity when shaken, q1 is preferably 1 or 2, and more preferably 2.

[0050] In the general formula (b2′), p1 is 0 or 1. From the viewpoint of good fluidity when shaken, p1 is preferably 0.

[0051] From the viewpoint of good fluidity when shaken, a combination in which q1 is 1 or 2 and p1 is 0 in the general formula (b2') is preferred.

[0052] AO in the general formula (b2') is an oxyalkylene group having 2 to 4 carbon atoms, and examples thereof include an oxyethylene group, an oxypropylene group, and an oxybutylene group. When AO is different in the average n1 repeating units, it may be randomly added or block added, or may contain an admixture of these. n1 in the general formula (b2) is 5 or more, preferably 10 or more, more preferably 20 or more, and 150 or less, preferably 140 or less, more preferably 100 or less, even more preferably 100 or less, and even more preferably 60 or less.

[0053] From the viewpoint of good fluidity when vibrated, it is preferable that AO contains an oxyethylene group. Also, from the viewpoint of good fluidity when vibrated, the content (mol%) of oxyethylene group in AO is preferably 70 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, and even more preferably 100 mol%. Furthermore, n1 in general formula (b2') is 5 or more, preferably 10 or more, more preferably 20 or more, and 150 or less, preferably 140 or less, more preferably 100 or less, even more preferably 100 or less, and even more preferably 60 or less.

[0054] Next, the general formula (b3) will be described. R in general formula (b3) 9b Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a hexyl group, a 2-ethylhexyl group, a cyclohexyl group, an octyl group, a cyclooctyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, a hydroxymethyl group, a 2-hydroxyethyl group, a 3-hydroxypropyl group, a 4-hydroxybutyl group, a 3,4-dihydroxybutyl group, etc. From the viewpoint of good fluidity when vibrated, a methyl group or a 2-hydroxyethyl group is preferred.

[0055] The structural unit (B3) represented by general formula (b3) can be introduced into the copolymer (B) by using a monomer represented by general formula (b3') as the raw material. [ka] [In the formula, R 9b represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.

[0056] R in general formula (b3') 9b Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a hexyl group, a 2-ethylhexyl group, a cyclohexyl group, an octyl group, a cyclooctyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, a hydroxymethyl group, a 2-hydroxyethyl group, a 3-hydroxypropyl group, a 4-hydroxybutyl group, a 3,4-dihydroxybutyl group, etc. From the viewpoint of good fluidity when vibrated, a methyl group or a 2-hydroxyethyl group is preferred.

[0057] Even if the structural unit (B3) is not contained in the copolymer (B), good fluidity during vibration is sufficiently exhibited.

[0058] From the viewpoint of good fluidity during vibration, the proportion of the total of the structural units (B1), (B2), and (B3) is preferably 6 mass% or more, and more preferably 6.5 mass% or more, and is preferably 20 mass% or less, and more preferably 18 mass% or less.

[0059] From the viewpoint of good fluidity when shaken, the weight average molecular weight (Mw) of the component (B) is preferably 10,000 or more, more preferably 20,000 or more, and is preferably 80,000 or less, more preferably 70,000 or less.

[0060] The (B) component can be produced under the conditions for copolymerization of general-purpose vinyl polymers. For example, water can be used as the solvent. The reaction temperature can be in the range of 50°C to 100°C. The reaction time varies depending on the reaction temperature, but can be in the range of 0.5 hours to 10 hours. The pH during production is preferably 3 or less.

[0061] The amount of component (B) added is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, based on the hydraulic powder in the hydraulic composition, from the viewpoint of good fluidity during vibration and economic efficiency, and is preferably 0.5% by mass or less, more preferably 0.3% by mass or less.

[0062] The component (B) may be added as it is in the form of a copolymer, or may be added together with a suitable solvent (or dispersion medium). The solvent (or dispersion medium) is preferably water, and adding it together with water is preferred from the viewpoint of convenience. When it is added as a water solution (or dispersion), it is necessary to add the amount of water to the amount of water essential for the composition of the present application, but this amount can be ignored when the concentration of the water solution (or dispersion) is high or the amount added is small.

[0063] The mass ratio of the (B) component to the (A) component, (B) / (A), is preferably 0.01 or more, more preferably 0.1 or more, even more preferably 0.2 or more, and is preferably less than 5.0, more preferably less than 3.5.

[0064] Next, the component (C) will be described. The admixture for hydraulic compositions of the present invention contains one or more salts of hydroxycarboxylic acids containing one or more hydroxyl groups and one or more carboxyl groups in one molecule. The hydroxycarboxylic acids used as raw materials for the salts may be either aliphatic hydroxycarboxylic acids or aromatic hydroxycarboxylic acids, but aliphatic hydroxycarboxylic acids are preferred in terms of availability and safety. Among these, aliphatic hydroxycarboxylic acids having 2 to 8 carbon atoms are more preferred. Specific examples include glycolic acid, which has two carbon atoms; lactic acid, tartronic acid, and glyceric acid, which have three carbon atoms; 2-hydroxybutyric acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, tartaric acid, malic acid, 2-hydroxyfumaric acid, 2,3-dihydroxyfumaric acid, 2-hydroxymaleic acid, 2,3-dihydroxymaleic acid, 2-methyltartronic acid, and hydroxymethanetricarboxylic acid, which have four carbon atoms; citramalic acid and 2-hydroxyglutaric acid, which have five carbon atoms; pantoic acid, citric acid, isocitrate, 2-hydroxycitric acid, mevalonic acid, leucic acid, gluconic acid, and aldaric acid, which have six carbon atoms; quinic acid, shikimic acid, and 2-methylcitric acid, which have seven carbon atoms; and 8-hydroxyoctanoic acid, which has eight carbon atoms.

[0065] Among the hydroxycarboxylic acids given as examples, those having an asymmetric carbon include all of their optical isomers. The optical isomers can be used alone, or the racemates can be used. The racemates are preferred from the viewpoints of availability and economy.

[0066] As the hydroxycarboxylic acid, one or more selected from gluconic acid, malic acid, and tartaric acid are preferred because they have good fluidity when shaken.

[0067] These hydroxycarboxylic acids are preferably used in the form of a salt in which all or part of the hydrogen atoms of the carboxyl group are substituted with an ion of an alkali metal such as sodium or potassium, an alkaline earth metal ion such as calcium, an ammonium ion, or a mono-, di-, tri- or tetra-alkylammonium ion, in view of good fluidity when shaken. In view of easy availability, it is preferable to use the hydroxycarboxylic acids as a sodium salt substituted with sodium.

[0068] The mass ratio of the component (C) to the component (A), (C) / (A), is preferably 0.05 or more, more preferably 0.1 or more, even more preferably 0.2 or more, and is preferably less than 3.0, more preferably less than 2.0.

[0069] The admixture for hydraulic compositions of the present invention may contain additives such as foaming agents, thickeners, foaming agents, preservatives, and antifoaming agents in addition to the components (A), (B), and (C). These additives may be contained in an amount of 0.01% by mass or more and 2% by mass or less relative to the components (A) and (B). The antifoaming agents include one or more types of antifoaming agents selected from silicone-based antifoaming agents, fatty acid ester-based antifoaming agents, ether-based antifoaming agents, polyalkylene oxide-based antifoaming agents, alkyl phosphate ester-based antifoaming agents, and acetylene glycol-based antifoaming agents. The defoaming agent is preferably one or more defoaming agents selected from silicone-based defoaming agents, fatty acid ester-based defoaming agents, and ether-based defoaming agents.

[0070] The admixture for hydraulic compositions of the present invention can be added to a hydraulic composition containing hydraulic powder and water. The hydraulic powder is a powder that hardens when mixed with water, and examples thereof include ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, sulfate-resistant Portland cement, low-heat Portland cement, white Portland cement, and ecocement (e.g., JIS R5214, etc.). Among these, from the viewpoint of shortening the time required for the hydraulic composition to reach the required strength, cement selected from early-early-strength Portland cement, ordinary Portland cement, sulfate-resistant Portland cement, and white Portland cement is preferred, and cement selected from early-early-strength Portland cement and ordinary Portland cement is more preferred.

[0071] The hydraulic powder may contain blast furnace slag, fly ash, silica fume, anhydrous gypsum, etc., or may contain non-hydraulic limestone fine powder. As the hydraulic powder, blast furnace cement, fly ash cement, or silica fume cement, which is a mixture of cement and blast furnace slag, fly ash, silica fume, etc., may be used. It is preferable to contain blast furnace slag or fly ash from the viewpoint of using a low-quality hydraulic composition. Examples of blast furnace slag and fly ash include those described in JIS R5201.

[0072] The water contained in the hydraulic composition is preferably water that is free of impurities and is appropriately purified, but well water and industrial water may also be used. Tap water, purified water, and ion-exchanged water are preferred.

[0073] The ratio of water to the hydraulic powder is preferably 20% by mass or more, more preferably 25% by mass or more, even more preferably 30% by mass or more, and preferably 70% by mass or less, more preferably 65% ​​by mass or less, even more preferably 60% by mass or less.

[0074] From the viewpoint of good fluidity during vibration, the amount of component (B) added is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, based on the hydraulic powder in the hydraulic composition, and is preferably 0.5% by mass or less, more preferably 0.4% by mass or less, and even more preferably 0.3% by mass or less. EXAMPLES

[0075] <Examples and Comparative Examples> The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the following descriptions.

[0076] The materials used in the examples and comparative examples are shown below. <Component (A)> The sodium salt of lignin sulfonic acid was used as the lignin derivative of component (A). Ultragin NA, manufactured by Borregaard, with a sugar content of 1% or less, was used as the sodium salt of lignin sulfonic acid.

[0077] <(B) component> The following compounds were used as raw materials for the structural units (B1), (B2) and (B3) to produce copolymer (B). Raw material for structural unit (B1): acrylic acid Raw material for structural unit (B2): polyethylene glycol isoprenyl ether (hereinafter referred to as TPEG) represented by the following general formula (1), [ka] [In the formula, nb1 is the average number of moles added and is 20, 60, 65, or 66.] In addition, the ethers of general formula (1) are referred to as TPEG20, TPEG60, TPEG65 and TPEG66, respectively, in accordance with the values ​​of nb1. Or, polyethylene glycol (2-methyl-2-propenyl) ether represented by the following general formula (2): [ka] [In the formula, nb2 is the average number of moles added, which is 63.] In addition, the ether of general formula (2) corresponding to the value of nb2 is referred to as HPEG63. Raw material for structural unit (B3): 2-hydroxyethyl acrylate

[0078] <(C) component> Sodium gluconate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Sodium tartrate dihydrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Sodium malate 0.5 hydrate (Fuso Chemical Co., Ltd.)

[0079] <Production of component (B) by copolymerization reaction> Using (B-1) in Table 1 as an example, a method for producing the component (B) is shown below. 200 parts by mass of TPEG60 and 128 parts by mass of water were charged into a glass reaction vessel equipped with a stirrer, and the mixture was replaced with nitrogen while stirring, and the temperature was raised to 80°C in a nitrogen atmosphere. Then, 0.9 parts by mass of hydrogen peroxide (35% by mass aqueous solution) was added. An aqueous solution in which 27.8 parts by mass of acrylic acid was dissolved in 41.7 parts by mass and an aqueous solution in which 1.4 parts by mass of 3-mercaptopropionic acid was dissolved in 45.4 parts by mass of water were each added dropwise over 3 hours, and an aqueous solution in which 0.4 parts by mass of L-ascorbic acid was dissolved in 38.4 parts by mass of water was added dropwise into the vessel over 3.5 hours. Then, the mixture was aged at the same temperature (80°C) for 1 hour. After the aging was completed, the mixture was neutralized with 16.1 parts by mass of a 48% aqueous sodium hydroxide solution to obtain an aqueous solution containing a copolymer (B) having a weight average molecular weight of 35,000. According to the above method, the component (B) of the examples and comparative examples shown in Table 1 was produced. [Table 1]

[0080] <Other materials> Cement: Ordinary Portland cement manufactured by Taiheiyo Cement Corporation and Sumitomo Osaka A 1:1 mixture of ordinary Portland cement (density 3.16 g / cm3) manufactured by Cement Co., Ltd. 3 ) Fine aggregate: mountain sand, density 2.72g / cm 3

[0081] <Production of hydraulic composition> 400 parts by weight of cement and 700 parts by weight of fine aggregate were added to a mortar mixer specified in JIS R5201, and dry mixing (60 rpm, 10 seconds) was performed. Thereafter, 160 parts by mass of water containing components (A), (B), and (C) in the ratio to the cement shown in Table 2 was added, and the mixture was kneaded (60 rpm, 120 seconds) to prepare the hydraulic composition shown in Table 2.

[0082] Using the hydraulic compositions of the Examples and Comparative Examples in Table 2, fluidity during vibration was evaluated. [Table 2]

[0083] <Evaluation of fluidity when shaken> The evaluation of fluidity during vibration was conducted according to JIS R5201, Section 12. Flow test. The details are as follows. The hydraulic composition immediately after mixing was filled into a flow cone (upper diameter 70 mm × lower diameter 100 mm × height 60 mm) described in JIS R5201 placed on a flow table, and the flow cone was removed vertically to measure the fluidity. Note that the smaller the fluidity immediately after filling, the clearer the effect of the fluidity during vibration in the admixture for hydraulic compositions of the present invention, so the amounts of (A), (B) and (C) components were adjusted so that the flow immediately after filling was 100 mm. The mortar was then dropped 15 times over a 15-second period, and the diameter of the mortar after it spread was measured to the nearest 1 mm in the direction in which it was deemed to be maximum and in the direction perpendicular to this, with the test being conducted only once. The fluidity obtained after 15 drops was regarded as the fluidity upon vibration. The flow value after 15 vibrations was divided by the flow value immediately after mixing (100 mm) to determine the fluidity improvement rate upon vibration. The results are shown in Table 3.

[0084] [Table 3]

[0085] As is clear from Examples 1 to 9 in Table 3, by using an admixture containing component (C), the flow value after 15 vibrations was 160 to 170 mm, indicating that fluidity was improved. On the other hand, when only the (A) component or the (B) component was used, the flow values ​​after 15 vibrations were low at 145 and 152 mm. When an admixture not containing the (C) component was used (Comparative Examples 3, 5 to 7), the flow values ​​after 15 vibrations were also low at 152 to 157 mm. Furthermore, the flow value after 15 vibrations in Comparative Example 4, which did not contain the (B) component, was also 157 mm. In addition, even when the (A), (B) and (C) components are included, when (B-6) having a small average number of moles of oxyethylene groups added is used as the (B) component, it was found that the fluidity during vibration is not improved (Comparative Examples 8 and 9). Although the detailed cause of this is unknown, it is believed that the average number of moles of oxyethylene groups added, which is a factor of the steric repulsion of the (B) component, is important. The estimated mechanism is that when components (A), (B), and (C) are used in combination, component (C) has the smallest molecular weight, so it instantly adsorbs to the cement particles, increasing the free water, and then components (A) and (B) adsorb, further increasing the free water and increasing the fluidity. However, for manufacturing reasons, polyacrylic acid remains in component (B), which crosslinks the cement particles and inhibits the fluidity. However, when vibration is applied, the crosslinks break down, and it is thought that when the average number of moles of oxyethylene groups added in component (B) is small, that is, when the length of the oxyethylene groups is short, the steric repulsion is weak, so the fluidity does not increase when vibration is applied. Therefore, from the viewpoint of fluidity when vibration is applied, it is presumed that the average number of moles of oxyethylene groups added is preferably 45 or more. From the above, it is clear that in order to show a good post-vibration fluidity improvement rate after 15 vibrations, all of components (A), (B), and (C) are essential, and the average number of moles of oxyethylene groups added in component (B) is important.

Claims

1. An admixture for a hydraulic composition, comprising the following components (A), (B) and (C): Component (A): Lignin derivative. (B) Component: General formula (b1) 【Chemistry 1】 [In the formula, M １ｂ R represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. １ｂ , R ２ｂ and R ３ｂ are the same or different and each represents a hydrogen atom, a methyl group, or a group represented by the general formula -(CH ２ ) ｒ COOM ２ｂ (2b) [wherein r represents 0, 1 or 2; M ２ｂ represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. ２ ) ｒ COOM ２ｂ (2b) is -COOM １ｂ or other -(CH ２ ) ｒ COOM ２ｂ may be bonded to form an acid anhydride bond -C(=O)-O-C(=O)-, in which case, M １ｂ , M. ２ｂ does not exist.] A structural unit (B1) represented by the formula: General formula (b2) 【Chemistry 2】 [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q1 represents 0, 1 or 2, p1 represents 0 or 1, and n1 represents the average number of moles of AO added and represents a number of 5 to 150. ４ｂ , R ５ｂ and R ６ｂ are the same or different and each represents a hydrogen atom, a methyl group, a group represented by the general formula -(CH ２ ) ｓ COOM ３ｂ (3b) [wherein s represents 0, 1 or 2; M ３ｂ represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. ２ ) ｑ２ (CO) ｐ２ O (AO) ｎ２ R ８ｂ (4) [In the formula, AO represents an oxyalkylene group having 2 to 4 carbon atoms, q2 represents 0, 1 or 2, p2 represents 0 or 1, n2 represents the average number of moles of AO added and represents a number of 5 to 150, and R ８ｂ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Structural unit (B2) represented by the formula: and optionally a compound represented by the general formula (b3): 【Chemistry 3】 [In the formula, R ９ｂ represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom. A copolymer having a structural unit (B3) represented by the following formula: (C) Hydroxycarboxylate.

2. 2. The admixture for hydraulic compositions according to claim 1, wherein the hydroxycarboxylate is an aliphatic hydroxycarboxylate.

3. 3. The admixture for hydraulic compositions according to claim 1 or 2, wherein the hydroxycarboxylate has 2 to 8 carbon atoms.

4. 4. The admixture for hydraulic compositions according to claim 1, wherein the hydroxycarboxylate is a gluconate, a tartrate or a malate.

5. The admixture for hydraulic compositions according to any one of claims 1 to 4, wherein the hydroxycarboxylate is a sodium salt.

6. 6. The admixture for hydraulic compositions according to claim 1, wherein the mass ratio of the component (C) to the component (A), (C) / (A), is 0.05 or more and less than 3.

0.

7. The admixture for hydraulic compositions according to any one of claims 1 to 6, wherein the lignin derivative is lignin sulfonic acid and / or a salt thereof.

8. The admixture for hydraulic compositions according to any one of claims 1 to 7, wherein p1 in the general formula (b2) is 0.

9. The admixture for hydraulic compositions according to any one of claims 1 to 8, wherein in general formula (b2), q1 is 1 or 2, and p1 is 0.

10. The admixture for hydraulic compositions according to any one of claims 1 to 9, wherein q1 in the general formula (b2) is 2 and p1 is 0.

11. The admixture for hydraulic compositions according to any one of claims 1 to 10, wherein the ratio of the total of the structural units (B1) and (B3) to the total of the structural units (B1), (B2) and (B3) is 6 mass% or more and 20 mass% or less.

12. The admixture for hydraulic compositions according to any one of claims 1 to 11, wherein the mass ratio of the component (B) to the component (A), (B) / (A), is 0.01 or more and less than 5.

0.

13. The admixture for hydraulic compositions according to any one of claims 1 to 12, wherein the weight average molecular weight (Mw) of component (B) is 10,000 or more and 80,000 or less.

14. The admixture for hydraulic compositions according to any one of claims 1 to 13, further comprising water.

15. A hydraulic composition comprising a hydraulic powder containing cement, water, and the admixture for hydraulic compositions according to any one of claims 1 to 14.

16. The hydraulic composition according to claim 15, wherein the ratio of water to the hydraulic powder is 20% by mass or more and 70% by mass or less.

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