JP4381923B2 - Additive for hydraulic composition - Google Patents

Description

  The present invention relates to a hydraulic composition, and more particularly to an additive for a hydraulic composition that can improve the workability of concrete. More specifically, by reducing the influence of fine particles contained in the aggregate, it is possible to improve the fresh performance and condition of concrete such as concrete viscosity and fluidity retention, and to provide concrete with excellent workability. The present invention relates to an additive for hydraulic compositions.

  In recent years, formalin condensates such as naphthalene and melamine, and polycarboxylic acid dispersants that have a high water reduction rate regardless of the amount added have become widespread as high-performance water reducing agents used in the civil engineering and construction fields. . In general, a high-performance water reducing agent is used for high-strength blending with a small amount of unit water and a large amount of cement as compared with a water reducing agent such as lignin. Therefore, when a high-performance water reducing agent and a lignin-based water reducing agent are added to each recommended formulation, for example, when concrete having the same fluidity as slump 18 cm is produced, the concrete added with the high-performance water reducing agent is (For example, the water-cement ratio is small), the concrete viscosity is higher than the lignin type, and the workability tends to be lowered. For this reason, construction sites in the civil engineering / architecture field require admixtures that can produce concrete that is easy to handle, even in high-strength blends, compared to current high-performance water reducing agents, that is, workability of concrete, that is, low viscosity, good fluid retention. It has been.

  On the other hand, several additives for hydraulic compositions are known as techniques for improving low viscosity and fluidity retention and imparting good workability in the fresh properties of hydraulic compositions. For example, a specific polyamine monomer (A), a specific unsaturated carboxylic acid monomer (B), and a polyalkylene glycol monomer (C) are A: B: C = 10 to 40% by mass. : 10 to 40% by mass: A cement dispersant mainly composed of a polymer copolymerized at a ratio of 50 to 80% by mass can be used as a dispersant for ultra-high-strength concrete and has excellent on-site workability. Is disclosed (for example, Patent Document 1).

  In addition, a cement admixture comprising a polycarboxylic acid polymer and a polyalkyleneimine alkylene oxide adduct, with respect to a cement admixture that can be made viscous so that it is easy to work at a site where concrete is handled, A cement admixture mainly composed of a polycarboxylic acid-based polymer obtained by copolymerizing the polycarboxylic acid-based copolymer with a polyalkyleneimine alkylene oxide adduct monomer is disclosed (for example, Patent Document 2). ).

JP 2000-191356 A JP 2003-342050 A

  Polycarboxylic acid-based dispersants are widely used in the industry because they have excellent dispersibility and can secure strength even in concrete having a small water-cement ratio. However, in recent years, with the depletion of high-quality fine aggregates such as domestic river sand, the proportion of aggregates that have not been actively used is increasing. The hydraulic composition using such fine aggregate has a high fresh state viscosity even at a normal water cement ratio (W / C), or the coating state of the coarse aggregate with mortar becomes unstable. It turned out that workability tends to be lowered. It is difficult to sufficiently cope with this problem even with conventional polycarboxylic acid-based dispersants and the techniques of the above-mentioned patent documents.

  The present invention has been made in consideration of such a situation, and improves fluid retention, fresh viscosity, and mortar state even for hydraulic compositions containing fine aggregates that are not of high quality. An object of the present invention is to provide an additive for a hydraulic composition that can give excellent properties to a hydraulic composition such as concrete.

  The present invention relates to an additive for a hydraulic composition containing a cationic polymer (A) containing quaternary nitrogen.

  The present invention also relates to a hydraulic composition containing the additive for hydraulic composition of the present invention, water, hydraulic powder and / or aggregate.

  According to the present invention, even for a hydraulic composition containing fine aggregates that are not high in quality, the fluidity retention, the viscosity at the time of freshness and the state of mortar are improved, and the hydraulic composition such as concrete is excellent. A hydraulic composition additive that imparts properties can be provided.

  As the cationic polymer (A) used in the present invention, a quaternary nitrogen, a polyoxyalkylene group comprising an alkyl group having 1 to 22 carbon atoms, an oxyalkylene group having 1 to 8 carbon atoms, and Formula (1)

Wherein R _{1 to} R ₅ may be the same or different and each represents an alkyl or alkenyl group having 1 to 22 carbon atoms, Z is —O— or —NY— (Y is A hydrogen atom or an alkyl group having 1 to 10 carbon atoms), and n is a number of 1 to 10. However, R ₁ and R ₃ may be incorporated into the polymer structure, in which case R ₁ and R ₃ are not present. A polymer to which a group selected from the above is bonded is preferable.

  Examples of the counter ion of the cationic polymer include anionic ions such as halogen ions, sulfate ions, alkyl sulfate ions, phosphate ions, and organic acid ions. When used for concrete, anionic ions other than halogen ions are preferred from the viewpoint of preventing corrosion of reinforcing bars.

  As the cationic polymer (A), a polymer in which the quaternary nitrogen is derived from a diallyldimethylammonium salt is also suitable.

  The cationic polymer (A) includes a (meth) acrylic acid monomer having a cationic group, a styrene monomer having a cationic group, a vinylpyridine monomer, a vinylimidazoline monomer, and diallyldialkyl. A polymer having a structure derived from a monomer selected from the group consisting of amine monomers is preferred.

Specific examples of the cationic polymer (A) include poly (diallyldimethylammonium salt), polymethacryloyloxyethyldimethylethylammonium salt, polymethacrylamidopropyltrimethylammonium salt, polytrimethylallylammonium salt, cationized polysaccharide derivatives such as Cationic starch, cationized cellulose, cationized hydroxyethyl cellulose and the like, which may be obtained by polymerizing a monomer having a quaternary salt structure, or may be obtained by quaternizing the corresponding polymer with a quaternizing agent. . These may not be homopolymers, and may be a copolymer with a copolymerizable monomer as required. Specifically, diallyldimethylammonium salt-SO ₂ copolymer, diallyldimethylammonium salt-acrylamide copolymer, diallyldimethylammonium salt-acrylic acid-acrylamide copolymer, methacryloyloxyethyldimethylethylammonium salt-vinylpyrrolidone copolymer, methacrylamide propyl And trimethylammonium salt-vinyl pyrrolidone copolymer. These may contain unreacted monomers, by-products, polymers of different cationization densities. These can be used in combination of two or more.

  Among the above, poly (diallyldimethylammonium salt), polymethacryloyloxyethyldimethylethylammonium salt, polymethacrylamidopropyltrimethylammonium salt, methacryloyloxyethyldimethylethylammonium salt-vinylpyrrolidone copolymer, and methacrylamidopropyltrimethylammonium salt-vinyl Cationic polymers selected from pyrrolidone copolymers are preferred, and among these, from the viewpoint of concrete production, those in which the counter ion is an alkyl sulfate ion, among them, ethyl sulfate and methyl sulfate are more preferred.

  Compounds derived from the group represented by the general formula (1) include methacryloyloxyethyltrimethylammonium salt, methacryloyloxyethyldimethylethylammonium salt, methacryloyloxypropyltrimethylammonium salt, methacryloyloxypropyldimethylethylammonium salt, methacrylamide Ethyltrimethylammonium salt, methacrylamideamidodimethylethylammonium salt, methacrylamideamidopropyltrimethylammonium salt, methacrylamidopropyldimethylethylammonium salt, acryloyloxyethyltrimethylammonium salt, acryloyloxyethyldimethylethylammonium salt, acryloyloxypropyltrimethylammonium salt, Acryloyloxypropyldimethyl Examples include tillammonium salt, acrylamidoethyltrimethylammonium salt, acrylamidoethyldimethylethylammonium salt, acrylamidopropyltrimethylammonium salt, acrylamidopropyldimethylethylammonium salt, and the like, and these are preferably alkyl sulfates, especially ethyl sulfate and methyl sulfate. .

The weight average molecular weight of the cationic polymer (A) is preferably 1000 or more, more preferably 1000 to 3 million, and particularly preferably 3000 to 500,000. This weight average molecular weight is measured by gel permeation chromatography under the following conditions.
Column: α-M (manufactured by Tosoh Corp.) 2 linked eluent: 0.15 mol / L Na sulfate, 1% acetic acid aqueous solution Flow rate: 1.0 mL / min
Temperature: 40 ° C
Detector: RI
Pullulan is used as molecular weight standard

  The cationic polymer (A) has a cationization density of 0.5 to 10 meq / g, more preferably 1 to 9 meq / g, particularly 3 to 8 meq / g, which improves workability of concrete (low viscosity and fluid retention) From the viewpoint of improvement of The cationization density can be measured by the method of Examples described later.

  By adding the cationic polymer (A) according to the present invention to concrete, the performance of the high-performance water reducing agent or high-performance AE water reducing agent (hereinafter referred to as high-performance water reducing agent) can be efficiently extracted, and the viscosity of the concrete can be reduced. It is considered that good workability resulting from the improvement of fluidity retention is obtained for the following reason.

  The cationic polymer (A) containing quaternary nitrogen as selected in the present invention has hitherto been considered unsuitable as a cement dispersant and has almost no cement dispersing ability of its own. Nevertheless, the reason why such a cationic polymer (A) provides an excellent effect is not necessarily clear, but the cationic polymer (A) of the present invention is a hydraulic powder such as a conventional cement dispersant. It is thought that it does not act on the body but acts on the fine aggregate to eliminate the cause of the deterioration of the fine aggregate. The cause of the deterioration of fine aggregates is derived from fine particles, clay minerals, and the like contained in the fine aggregates, and the cationic polymer (A) of the present invention has a property of selectively adsorbing or inclusion thereof. Therefore, the dispersant for hydraulic composition added for the preparation of the hydraulic composition can be effectively adsorbed on the particle surface of the cement, and the original performance (low viscosity due to dispersion action, aging from the liquid phase) It is considered that the fluidity retention by dynamic adsorption) can be sufficiently exhibited. Furthermore, the following can be considered.

  When the cationic polymer (A) is added to concrete, it quickly dissolves in water and has a positive charge. In general, many natural products are negatively charged in water, but fine sand particles and clay minerals have a strong negative surface. Therefore, since the cationic polymer (A) is adsorbed and aggregated on the surface of fine sand particles or clay mineral, the negatively charged surface area can be reduced. In particular, in the case of clay minerals, the swellability peculiar to clay minerals is suppressed at the same time as agglomeration, so that the trapping (inclusion phenomenon) of the high-performance water reducing agent in the clay mineral can be suppressed. For this reason, the high-performance water reducing agent effectively functions as much as it is added to the concrete, so that it is considered that the low viscosity of the concrete and good fluidity retention can be imparted. Therefore, the additive of the present invention is effective when used in combination with a general hydraulic composition admixture, but is particularly preferably used with a polycarboxylic acid-based admixture.

  The additive for a hydraulic composition of the present invention can contain a water reducing agent or an AE water reducing agent, and is at least one of a high performance water reducing agent and a high performance AE water reducing agent (hereinafter referred to as component (B)). It is preferable to contain.

  As the component (B) relating to the hydraulic composition additive of the present invention, one or more vinyl monomers (a) represented by the following general formula (2) and the following general formula (3) are used. A water-soluble copolymer (B1) [hereinafter referred to as copolymer (B1)] obtained by polymerizing a monomer mixture containing at least one vinyl monomer (b) to be produced is preferred.

[Wherein R ₆ and R ₇ are each a hydrogen atom or a methyl group, m1 is a number from 0 to 2, AO is an oxyalkylene group having 2 to 3 carbon atoms, and n is the average number of moles added. And is a number from 1 to 300, and X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ]

[Wherein R _{8 to} R ₁₀ are a hydrogen atom, a methyl group, and (CH ₂ ) _{m 2} COOM ₂ , respectively, and M ₁ and M ₂ are a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, and an alkyl, respectively. It is ammonium or substituted alkylammonium, m2 represents the number of 0-2. ]

In the case where M ₁ or M ₂ in the general formula (3) is an alkaline earth metal, the compound is a group obtained by removing M ₁ or M ₂ from the general formula (3) in M ₁ or M ₂ . It becomes a structure combined with the valence of the alkaline earth metal. When the compound has a plurality of —COO groups and M ₁ or M ₂ is an alkaline earth metal, a structure in which a plurality of —COO groups are closed via M ₁ or M ₂ may be used.

  As the monomer (a) represented by the general formula (2), a compound in which X is an alkyl group having 1 to 4 carbon atoms is preferable. Moreover, from the point of foam suppression property, what contains 80 mol% or more of oxyethylene groups in all the oxyalkylene groups is preferable. Specifically, dehydration of one-end alkyl-blocked polyalkylene glycol such as methoxy polyethylene glycol, methoxy polyethylene polypropylene glycol, ethoxy polyethylene glycol, ethoxy polyethylene polypropylene glycol, propoxy polyethylene glycol, propoxy polyethylene polypropylene glycol and acrylic acid, methacrylic acid or fatty acid Ethylene oxide (hereinafter referred to as “EO”), propylene oxide (hereinafter referred to as “PO”), etc. to esterified products with elementary (oxidized) reactants and dehydrogenation (oxidation) reactants of acrylic acid, methacrylic acid or fatty acids Adducts are used. The average added mole number n of the polyalkylene glycol is 1 to 300, preferably 2 to 180, more preferably 5 to 150, still more preferably 6 to 130, still more preferably, from the viewpoint of slump retention, polymerizability, and dispersibility. Is from 6 to 100, more preferably from 6 to 50, particularly preferably from 6 to 30, and both EO and PO adducts can be used in any of random addition, block addition, alternating addition, and the like.

  Examples of the monomer (b) represented by the general formula (3) include acrylic acid, methacrylic acid, crotonic acid, and metal salts thereof. Further, as the unsaturated dicarboxylic acid-based monomer, maleic anhydride, maleic acid, itaconic anhydride, itaconic acid, citraconic anhydride, citraconic acid, fumaric acid, or alkali metal salts, alkaline earth metal salts thereof, Ammonium salts and amine salts are used.

  The copolymer (B1) according to the present invention can be produced by polymerizing the above monomer mixture by a known method, for example, a solvent polymerization method disclosed in JP-A-7-223852. For example, in the presence of a polymerization initiator such as ammonium persulfate or hydrogen peroxide in water or a lower alcohol having 1 to 4 carbon atoms, if necessary, sodium bisulfite or mercaptoethanol is added to the monomer mixture. What is necessary is just to make it react at 50-100 degreeC by nitrogen atmosphere for 0.5 to 10 hours.

  (B) component which concerns on the additive for hydraulic compositions of this invention is a naphthalene type (Kao Co., Ltd. product: Mighty 150), a melamine type (Kao product: Mighty 150V-2), a polycarboxylic acid type (Kao product: Mighty) 3000, manufactured by NMB: Leo Build SP, manufactured by Nippon Shokubai Co., Ltd .: Aqualock FC600, Aqualock FC900, manufactured by Nippon Seika: Seakament 1100NT), etc., and particularly those containing a copolymer (B1) Is preferred. As these high-performance water-reducing agents and high-performance AE water-reducing agents, polycarboxylic acid systems are desirable from the viewpoint of reducing concrete viscosity and good fluidity retention.

  (B) The usage-amount of a component is 0.1 to 5 weight% (solid content conversion) in total with respect to hydraulic powder, Furthermore, 1 to 3.0 weight% is preferable.

  The cationic polymer (A) is 0.1 to 30 parts by weight (in terms of solid content), more preferably 0.5 to 20 parts by weight, based on 100 parts by weight of the component (B), preferably the copolymer (B1). In particular, it is preferably used at a ratio of 1 to 10 parts by weight. Within this range, the physical property improving effect of the hydraulic composition of the present invention is well expressed, and the dispersibility of the component (B) is sufficiently expressed.

  The hydraulic powder used in the hydraulic composition that is the target of the additive for the hydraulic composition of the present invention is a powder having physical properties that are cured by a hydration reaction, such as cement and gypsum. Can be mentioned. Preferred are ordinary portland cement, high belite cement, medium heat cement, early strong cement, super early strong cement, sulfate resistant cement, etc., and blast furnace slag, fly ash, silica fume, stone powder (calcium carbonate powder). Etc. may be added. In addition, the hydraulic composition finally obtained by adding sand, sand and gravel as aggregates to these powders is generally called mortar, concrete, etc., respectively.

The hydraulic composition has a water-powder ratio [weight percentage (% by weight) of water and powder in the slurry, usually abbreviated as W / P, but abbreviated as W / C when the powder is cement. The 20 to 65% by weight is preferred. Furthermore, 30 to 63% by weight, particularly 40 to 60% by weight is preferable. Moreover, the hydraulic powder used may be individual or mixed. Since the present invention has an effect of alleviating the influence of fine particles derived from the aggregate, the low-strength blend (for example, the strength at the age of 28 days is 18 to 18). 24N / mm ² ) and poor blending (for example, blending with a unit cement amount of 225 to 325 kg / m ³ ). Moreover, it is suitable in the material which contains many microparticles | fine-particles, such as a clay mineral, in the aggregate used.

  Moreover, the cationic polymer (A), the component (B), and hydraulic powder are premixed to prepare a hydraulic powder composition containing the additive for hydraulic composition of the present invention. it can.

  When the additive for hydraulic composition of the present invention is added to concrete (or mortar), the cationic polymer (A) and the component (B) can be added to the concrete in any order, but the cationic polymer (A) It is preferable to add it together with the component (B) from the viewpoint of workability, and it may be mixed before use. Further, the cationic polymer (A) and the component (B) may be in a liquid state or a powder state when added to the concrete. The additive for a hydraulic composition of the present invention comprises a cationic polymer and a component (B) that includes one of the components (I) and does not include the other, and the remaining one that does not include the composition (I). It can be comprised including the combination with the composition (II) containing.

  In addition, the hydraulic composition according to the present invention has other components such as an AE agent, a retarder, a fluidizing agent, an early strengthening agent, an accelerator, a foaming agent, and a foam, as long as the performance of the present invention is not impaired Agent, water retention agent, self-leveling agent, antifoaming agent, rust preventive agent, colorant, thickener, antifungal agent, crack reducing agent, swelling agent (material), polymer emulsion, dye, pigment, other surfactants One type or two or more types such as glass fiber can be used in combination. In addition, these components can also be mix | blended with the additive for hydraulic compositions of this invention.

  Using the cationic polymer (A), the high-performance water reducing agent (B), and the comparative compound shown below, the following examples were performed on the following concrete blend (1) or (2).

<Cationic polymer (A)>
A-1: poly (diallyldimethylammonium chloride), manufactured by Aldrich, low molecular weight product (weight average molecular weight 5000 to 20000 (labeled)), cationization density 6.13 meq / g (used as 40 wt% aqueous solution)
A-2: poly (diallyldimethylammonium chloride), manufactured by Aldrich, weight average molecular weight 100,000 to 200,000 (labeled), cationization density 6.19 meq / g (used as 20 wt% aqueous solution)
A-3: Poly (diallyldimethylammonium chloride), manufactured by Aldrich, weight average molecular weight of 400,000 to 500,000 (labeled), cationization density of 6.15 meq / g (used as 20 wt% aqueous solution)
A-4: polymethacryloyloxyethyldimethylethylammonium salt, weight average molecular weight 120,000, cationization density 3.63 meq / g (used as 36.5 wt% aqueous solution)
A-5: diallyldimethylammonium chloride-SO ₂ copolymer, weight average molecular weight 4000, cationization density 4.33 meq / g
A-6: Trade name Accurac 41 (Mitsui Cytec Co., Ltd.), weight average molecular weight 40,000, cationization density 7.10 meq / g (used as 50 wt% aqueous solution)
A-7: trade name Acurac 35 (Mitsui Cytec Co., Ltd.), weight average molecular weight 70,000, cationization density 7.11 meq / g (used as 50 wt% aqueous solution)
A-8: Trade name Accurac 57 (Mitsui Cytec Co., Ltd.), weight average molecular weight 250,000, cationization density 7.27 meq / g (used as 50 wt% aqueous solution)
A-9: cationized hydroxyethyl cellulose, weight average molecular weight 1,500,000, cationization density 1.08 meq / g

<High performance water reducing agent (B)>
B-1: (i) Methanol EO adduct (EO average addition mole number 10) Polycarboxylic acid-based EO adduct (weight average molecular weight 30000) of methacrylic acid ester / methacrylic acid = 40/60 (molar ratio); (B) Methanol EO adduct (EO average addition mole number 6) polycarboxylic acid-based EO adduct (weight average molecular weight 25000) of methacrylic acid ester / methacrylic acid = 55/45 (molar ratio), (B) Mixed at a solid content weight ratio of 1 / 3.4 (both were used as an aqueous solution containing 22% by weight in total)
B-2: naphthalene sulfonate formalin condensate (trade name Mighty 2000S, manufactured by Kao Corporation)

<Comparative compound>
Comparative cation compound: tetramethylammonium chloride (reagent), molecular weight 109.6, cationization density 9.12 meq / g (effective content 100%)
Polymer (1): Carboxymethylcellulose, trade name CMC1190 (Daicel Chemical Industries, Ltd.), anionic polymer Polymer (2): Polyvinylpyrrolidone, trade name K-60 (ISP TECHNOLOGIES INC.), Nonionic polymer

The cationization density measurement (colloidal titration) of the cationic polymer (A) was performed as follows. First, a cationic polymer (which may be pure or in solution) is dissolved in water adjusted to pH 3.0 with phosphoric acid. Toluidine blue indicator was added, titrated with a 1 / 400N polyvinyl potassium sulfate solution, and the color change was determined as the end point. The cationization density was determined by the following calculation formula.
Cationization density (meq / g) = 1/400 × f × (mL) / 1000 × 1000 × 1 / [(g) × (%) / 100]
f: Factor of 1 / 400N polyvinyl potassium sulfate solution
(mL): dripping amount of polyvinyl potassium sulfate solution
(g): Sample amount
(%): Sample concentration

<Concrete mix>

The materials used in Table 1 are as follows. For concrete blending (1), polycarboxylic acid-based high-performance water reducing agent B-1 is added to the cement at 0.14% by weight (in terms of solid content), and the concrete slump value immediately after kneading. 8 ± 1 cm.
Water (W): Tap water cement (C): Ordinary Portland cement, commercially available, density 3.16 g / cm ³
Fine aggregate (S): Kimitsu mountain sand, surface dry density 2.59 g / cm ³
Coarse aggregate (G): Crushed stone from Iejima, surface dry density 2.63 g / cm ³ , maximum dimension 20 mm

The materials used in Table 2 are as follows. For concrete blending (2), polycarboxylic acid-based high-performance water reducing agent B-1 is 0.2% by weight (in terms of solid content) with respect to cement, naphthalene-based high-performance water reducing agent B-2. Added 0.5% by weight to the cement, and the concrete slump value immediately after kneading was 21 ± 1 cm.
Water (W): Tap water cement (C): Ordinary Portland cement, commercially available, density 3.16 g / cm ³
Fine aggregate (S1): Crushed sand from Tanuma Town, Tochigi Prefecture, surface dry density 2.62 g / cm ³
Fine aggregate (S2): mountain sand from Sahara City, Chiba Prefecture, surface dry density 2.57 g / cm ³
Coarse aggregate (G): Crushed stone from Yokoze, Saitama Prefecture, surface dry density 2.70 g / cm ³ , maximum dimension 20 mm

Example 1 and Comparative Example 1
Under the blending conditions shown in Table 1, using a gravity mixer, cement (C), fine aggregate (S), and coarse aggregate (G) were added and kneaded for 10 seconds, and the cationic polymer (A) or Kneading water (W) containing a comparative compound and a high-performance water reducing agent was added, and 30 L of concrete was kneaded for 180 seconds. The produced concrete was discharged to a kneaded board, and the fluidity (slump value) for each elapsed time and the state evaluation of fresh concrete were measured according to the following test method. The results are shown in Table 3.

Example 2 and Comparative Example 2
Under the compounding conditions shown in Table 2, using a 100 L forced biaxial mixer, cement (C), fine aggregate (S), and coarse aggregate (G) were added and kneaded for 10 seconds to obtain a cationic polymer ( A) or kneading water (W) containing a comparative compound and a high-performance water reducing agent was added, and 30 L of concrete was kneaded for 90 seconds. The produced concrete was discharged to a kneaded board and measured for fluidity (slump value) at each elapsed time, L-type flow gradient test (viscosity evaluation), and fresh concrete state evaluation according to the following test methods. The results are shown in Table 4.

1. Fluidity (slump value): According to JIS A 1101 slump value (cm).

2. L-type flow inclination test (viscosity evaluation): One side of an L-type flow tester MIC-122-0-06 type (manufactured by Marui Co. LTD) equipped with a speedometer is lifted up to a height of 23 cm and given a predetermined inclination. After putting 2.56 L of concrete into the charging section, the partition plate was opened, and the speed at which the concrete passed 10 cm from the partition plate was measured (passing speed (cm / sec)). Further, the concrete was allowed to flow until it stopped, and the distance at which the concrete stopped flowing and the time until the concrete stopped were measured. The passing speed (cm / second) was evaluated according to the following criteria.
○: Passing speed is 40 cm / second or more Δ: Passing speed is 30 cm / second or more and less than 40 cm / second X: Passing speed is less than 30 cm / second

3. Evaluation of Fresh Concrete State The state of fresh concrete immediately after kneading was evaluated as follows based on the additive (Comparative Example 1-1 or 2-1) to which the cationic polymer (A) was not added.
○: The viscosity of concrete was low, and the resistance when stirring with a scoop decreased.
(Triangle | delta): The viscosity of concrete was a little low and the resistance at the time of stirring with a scoop decreased a little.
×: No change in concrete viscosity or resistance when stirring with a scoop.
XX: The viscosity of concrete was high, and the resistance during stirring with a scoop increased.

(Note) The addition amount (wt%) of the cationic polymer (A) in Table 3 is the wt% of the solid content of the additive with respect to the solid content of the high-performance water reducing agent (B).

  When the anionic polymer (1) is used as in Comparative Example 1-2 or when the nonionic polymer (2) is used as in Comparative Example 1-3, it is rather added to the concrete. A tendency to thicken was observed, the predetermined initial dispersibility could not be obtained, and the concrete condition deteriorated. On the other hand, in Examples 1-1 to 1-9 using a specific cationic polymer, the fluidity retention was improved as compared with no addition, and the state of the concrete was also improved.

(Note) The addition amount (wt%) of the cationic polymer (A) in Table 4 is the wt% of the solid content of the additive with respect to the solid content of the high-performance water reducing agent (B).

  In Comparative Example 2-2, since the comparative cation compound has a small molecular weight, it does not exhibit a sufficient effect, and the performance is the same as when it is not added. In addition, the anionic polymer (1) and nonionic polymer (2) used in Comparative Examples 2-3 and 2-4 have rather thickening tendency when added to concrete. The dispersibility could not be obtained, and the workability of the concrete decreased. On the other hand, in Examples 2-1 to 2-10, the fluidity retention was improved as compared with no addition, the viscosity was lowered, and the flow stop distance was almost the same as compared with no addition. In addition, since the flow stop time is short, it is considered that the same fluidity has excellent workability and workability.

Claims (7)

A hydraulic composition additive containing a cationic polymer (A) containing quaternary nitrogen and at least one of a high performance water reducing agent and a high performance AE water reducing agent (B) ,
Cationic polymer (A) containing quaternary nitrogen is a (meth) acrylic acid monomer having a cationic group, a styrene monomer having a cationic group, a vinylpyridine monomer, a vinyl imidazoline monomer Body, and a structure derived from a monomer selected from the group consisting of diallyldialkylamine monomers,
Hydraulic composition additive . In the quaternary nitrogen of the cationic polymer (A), a polyoxyalkylene group comprising an alkyl group having 1 to 22 carbon atoms, an oxyalkylene group having 1 to 8 carbon atoms, and the following formula (1)

Wherein R _{1 to} R ₅ may be the same or different and each represents a hydrogen atom or an alkyl or alkenyl group having 1 to 22 carbon atoms, and Z is —O— or —NY—. (Y is a hydrogen atom or a C1-C10 alkyl group), and n is a number of 1-10. However, R ₁ and R ₃ may be incorporated into the polymer structure, in which case R ₁ and R ₃ are not present. The additive for hydraulic compositions according to claim 1, wherein a group selected from The additive for hydraulic compositions according to claim 1 or 2, wherein the quaternary nitrogen of the cationic polymer (A) is derived from a diallyldimethylammonium salt. The high performance water reducing agent and / or the high performance AE water reducing agent is at least one vinyl monomer (a) represented by the following general formula (2) and a vinyl simple substance represented by the following general formula (3): It is a water-soluble copolymer (B1) obtained by polymerizing a monomer mixture containing at least one monomer (b). For hydraulic compositions according to any one of claims 1 to 3 . Additive.

[Wherein R ₆ and R ₇ are each a hydrogen atom or a methyl group, m1 is a number from 0 to 2, AO is an oxyalkylene group having 2 to 3 carbon atoms, and n is the average number of moles added. And is a number from 1 to 300, and X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ]

[Wherein R _{8 to} R ₁₀ are a hydrogen atom, a methyl group, and (CH ₂ ) _{m 2} COOM ₂ , respectively, and M ₁ and M ₂ are a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, and an alkyl, respectively. It is ammonium or substituted alkylammonium, and m2 represents a number of 0-2. ] The additive for hydraulic compositions according to any one of claims 1 to 4 , wherein the cationic polymer (A) has a cationization density of 0.5 to 10 meq / g and a weight average molecular weight of 1000 or more. The water according to any one of claims 1 to 5 , comprising 0.1 to 30 parts by weight of the cationic polymer (A) with respect to 100 parts by weight of the high-performance water reducing agent and / or the high-performance AE water reducing agent (B). Additive for hard composition. The hydraulic composition containing the additive for hydraulic compositions in any one of Claims 1-6 , water, hydraulic powder, and / or aggregate.