EP1725509A1 - Agent reduisant le retrait de sechage - Google Patents

Agent reduisant le retrait de sechage

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Publication number
EP1725509A1
EP1725509A1 EP05721220A EP05721220A EP1725509A1 EP 1725509 A1 EP1725509 A1 EP 1725509A1 EP 05721220 A EP05721220 A EP 05721220A EP 05721220 A EP05721220 A EP 05721220A EP 1725509 A1 EP1725509 A1 EP 1725509A1
Authority
EP
European Patent Office
Prior art keywords
group
structural unit
polymer
drying shrinkage
stands
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP05721220A
Other languages
German (de)
English (en)
Inventor
Takashi Yamamoto
Mari Masanaga
Hiroshi Kawabata
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Shokubai Co Ltd
Original Assignee
Nippon Shokubai Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nippon Shokubai Co Ltd filed Critical Nippon Shokubai Co Ltd
Publication of EP1725509A1 publication Critical patent/EP1725509A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
    • C04B24/24—Macromolecular compounds
    • C04B24/26—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B24/2641—Polyacrylates; Polymethacrylates
    • C04B24/2647—Polyacrylates; Polymethacrylates containing polyether side chains
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
    • C04B24/24—Macromolecular compounds
    • C04B24/26—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B24/2688—Copolymers containing at least three different monomers
    • C04B24/2694—Copolymers containing at least three different monomers containing polyether side chains
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/10—Esters
    • C08F220/26—Esters containing oxygen in addition to the carboxy oxygen
    • C08F220/28—Esters containing oxygen in addition to the carboxy oxygen containing no aromatic rings in the alcohol moiety
    • C08F220/285—Esters containing oxygen in addition to the carboxy oxygen containing no aromatic rings in the alcohol moiety and containing a polyether chain in the alcohol moiety
    • C08F220/286—Esters containing oxygen in addition to the carboxy oxygen containing no aromatic rings in the alcohol moiety and containing a polyether chain in the alcohol moiety and containing polyethylene oxide in the alcohol moiety, e.g. methoxy polyethylene glycol (meth)acrylate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/34—Non-shrinking or non-cracking materials

Definitions

  • This invention relates to a drying shrinkage-reducing agent.
  • this invention relates to a drying shrinkage-reducing agent for reducing the shrinkage occurring in a hydraulic material, particularly in concrete members, due to drying. More particularly, this invention relates to a drying shrinkage-reducing agent which manifests no dispersibility in an amount capable of attaining necessary drying shrinking-reducing properties and, when used in combination with a dispersing agent, acquires ability to adjust the dispersibility and the drying shrinkage-reducing properties fit for the purpose.
  • hydraulic materials Since hydraulic materials give cured substances excelling in strength and durability, they have been widely used in a cement composition including cement paste, mortar, and concrete and have become indispensable for the construction of civil engineering and constructional structures.
  • the hydraulic materials of this quality after being cured, incur dispersion of an unaltered water component remaining therein owing to an atmospheric temperature and humidity and suffer the drying shrinkage ascribable thereto to proceed.
  • the concrete building is gradually shrunken due to drying. Since the steel reinforcement induces no such change of shape, strain occurs between the concrete building and the steel reinforcement and incurs crack on the surface of the concrete building.
  • JP-A 2001-247,366 discloses a polymer formed by graft polymerizing an ethylenically unsaturated carboxylic acid with an alkoxy polyalkylene glycol.
  • drying shrinkage-reducing agent disclosed in JP-A 2001-247,346, however, has dispersibility.
  • drying shrinkage-reducing agent When such a drying shrinkage-reducing agent is used in an increasedamount so as to attain desired drying shrinkage-reducing property, therefore, it manifests dispersibility in excess, and thus a problem arises that a desired drying shrinkage-reducing effect can be obtained with much difficulties.
  • This invention has been attained in consideration of the situations as mentioned above and has an object to provide a drying shrinkage-reducing agent which can manifest outstanding drying shrinkage-reducing -ability.
  • drying shrinkage-reducing agent as used herein is referred to as an agent capable of repressing the shrinkage of a hydraulic material due to drying.
  • This invention has another object to provide a drying shrinkage-reducing agent which has no dispersibility in an amount capable of attaining necessary drying shrinking-reducing properties and, when used in combination with a dispersing agent, acquires an ability to adjust the dispersibility and the drying shrinkage-reducing properties fit for the purpose.
  • a drying shrinkage-reducing agent for a hydraulic material containing a structural unit having a hydrophobic group as an essential component and manifesting a specific surface tension particularly a drying shrinkage-reducing agent for a hydraulic material containing a polymer having a specific structure, can manifest excellent drying shrinkage-reducing properties, does not manifest dispersibility even by an increase in the used amount, and when used in combination with a dispersing agent, acquires an ability to easily adjust the dispersibility and drying shrinkage-reducing properties fit for the purpose.
  • a drying shrinkage-reducing agent which comprises a polymer containing as an essential component at least one structural unit (I) represented by the following formula (1) : [Chemical 1 ] R 1 R 2 - ( C - C ) - ( 1 ) I I R 3 C O O R 4 wherein R 1 , R 2 , and R 3 independently stand for a hydrogen atom, a methyl group, or a -(CH 2 ) p COOX group, wherein X stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammoniumgroup, anorganic amine group, or a hydrocarbon group, and p is an integer of 0 - 2; and R 4 stands for a hydrocarbon group of 4 - 30 carbon atoms, and exhibiting surface tension in the range of 25 - 50 mN/m in a solution containing 0.2 mass% of the polymer in a cement supernatant.
  • structural unit (I) represented by the following formula (1) : [Chemical 1
  • the polymer preferably contains as essential components at least one structural unit (I) represented by the formula (1) mentioned above; and at least one structural unit (II) selected among- a structural unit (Il-a) represented by the following formula (2) : [Chemical 2] R 5 R 7 I I - ( C - C ) - ( 2 )
  • R 6 ( C H 2 ) s C O O ( R 8 O ) U - R 9
  • R 5 , R 6 and R 7 independently stand for a hydrogen atom or a methyl group
  • s is an integer of 0 - 2
  • R 8 0 stands for one oxyalkylene group of 2 - 18 carbon atoms or a mixture of two or more such oxyalkylene groups
  • u stands for an average addition mol number of oxyalkylene group (R 8 0) and is in the range of 1 - 300
  • R 9 stands for a hydrogen atom or a hydrocarbon group of 1 - 30 carbon atoms, and a structural unit (Il-b) represented by the following formula (3) : [Chemical 3]
  • R 10 , R 11 and R 12 independently stand for a hydrogen atom or a methyl group; x is an integer of 0 - 2; R 13 0 stands for one oxyalkylele group of 2 - 18 carbon atoms or a mixture or two or more such groups; y stands for an average addition mol number of the oxyalkylene group (R 13 0) and is in the range of 1 - 300; and R 14 stands for a hydrogen atom or a hydrocarbon group of 1 - 30 carbon atoms, and contains at least one structural unit (III) represented by the following formula (4) : [Chemical 4] R 1 5 R 1 7
  • R 15 , R 16 and R 17 independently stand for a hydrogen atom, a methyl group, or a -(CH 2 ) q COOZ', wherein Z' stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group, or an organic amine group, and q is an integer of 0 - 2; and Z stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group, or an organic amine group, provided that if COOZ' and COOZ are present in the total number of not less than 2, two of them may form an anhydride, in a proportion in the range of 0 - 30 mass% based on the total mass of the polymer.
  • a shrinkage-reducing composition which contains at least one drying shrinkage-reducing agent of this invention and a dispersing agent.
  • the drying shrinkage-reducing agent for a hydraulic material of this invention is characterized by comprising a polymer containing at least one structural unit (I) represented by the aforementioned formula (1) and exhibiting surface tension in the range of 25 - 50 mN/m in a solution containing 0.2 mass% of the polymer in a cement supernatant. Since such a polymer can significantly lower the surface tension of water, it can effectively repress the shrinkage of a cured cement product and manifest outstanding drying shrinkage-reducing properties.
  • the drying shrinkage-reducing agent of this invention preferably comprises a polymer which contains as essential components (A) at least one structural unit (I) represented by the aforementioned formula (1) and (B) at least one structural unit (II) selected among the structural unit (Il-a) represented by the above formula (2) and the structural unit (Il-b) represented by the above formula (3) ; and further contains (C) at least one structural unit (III) represented by the above formula (4) in a proportion in the range of 0 - 30 mass% based on the total mass of the polymer.
  • a polymer used in an amount proper for obtaining a necessary drying shrinkage propertymanifests no dispersibility Such a polymer used in an amount proper for obtaining a necessary drying shrinkage propertymanifests no dispersibility.
  • the drying shrinkage-reducing agent containing this polymer when used in combination with a dispersing agent, permits easy adjustment of a drying shrinkage-reducing property and dispersibility fit for the purpose.
  • the drying shrinkage-reducing agent of this invention when applied to such hydraulic materials as cement paste, mortar, and concrete, to manifest outstanding crack-repressing effects, can enhance the durability of a cured product, exalt the safety of civil engineering and constructional structures, repress the cost of repair, and enjoy prominent general-purpose properties.
  • the first aspect of this invention is to provide a drying shrinkage-reducing agentwhichcomprises apolymer containing as an essential component at least one structural unit (I) (occasionally referred to simply as "structural unit (I) in the specification) represented by the following formula (1) : [Chemical 5] R 1 R 2 I I - (c-c) - (1) I I R 3 COOR 4 and exhibiting surface tension in the range of 25 - 50 mN/m in a solution containing 0.2 mass% of the polymer in a cement supernatant (occasionally referred to simply as "surface tension” in the specification) .
  • structural unit (I) (occasionally referred to simply as "structural unit (I) in the specification) represented by the following formula (1) : [Chemical 5] R 1 R 2 I I - (c-c) - (1) I I R 3 COOR 4 and exhibiting surface tension in the range of 25 - 50 mN/m in a solution containing 0.2 mass% of the polymer in a cement supern
  • the drying shrinkage is caused by the tensile stress exerted on the interface between water in a capillary and a cured product by water when the water moves through the capillary in the cured cement product in consequence of drying.
  • the polymer according to this invention is consideredto derive from the introduction of the hydrophobic group of R 4 in the structural unit (I) the ability to lower the interfacial tension between the cured cement product and the water, reduce the tensile stress of water which causes the drying shrinkage, and consequently repress the drying shrinkage.
  • the polymer in addition to the structural unit (I) , preferably contains as essential components at least one structural unit (II) selected among the structural unit (Il-a) (occasionally referred to briefly as “structural unit (Il-a)" in the specification) represented by the following formula (2) : [Chemical 6] R 5 R 7 I I - (C - C) - (2) I I R 6 (CH 2 ) s COO (R 8 O) U -R 9 and the structural unit (Il-b) (occasionally referred to briefly as "structural unit (Il-b)” in the specification) represented by the following formula (3) : [Chemical 7] R 10 R 12 I I - (C - C) - (3) I I R 11 (CH a ) ⁇ O (R 13 O) y -R 14 and further contains at least one structural unit (III) ' (occasionally referred to simply as "structural unit (III)” in the specification) represented by the following formula (4): [Chemical 8] R 1
  • the polymer canmanifest water-solubility without showing dispersibility and, the combined use with a dispersing agent permits easy adjustment of dispersibility and drying shrinkage-reducing properties proper for the purpose.
  • the structural unit (III) is present in the polymer at a proportion exceeding 30 mass%, this overage would possibly result in incorporating an excess amount of acid into the polymer, suffering the formed polymer to be adsorbed on cement and eventually manifest dispersibility, and further inducing such problems as retarding the hardening of cement.
  • the structural unit (II) may function to impart water-solubility to the polymer.
  • the drying - shrinkage-reducing agent of this invention can be advantageously used in various portland cements including ordinary, high-early-strength, moderate heat, low heat, and sulfate resistant, hydraulic cements such as Blite-rich cement, calcium-aluminate cement, portlandblast furnace slag cement, portland fly-ash cement, and various blended cements, or other hydraulic materials than cement such as gypsum for the purpose of effectively reducing drying shrinkage.
  • the polymer according to this invention contains the structural unit (I) as an essential component and essentially exhibits surface tension in the range of 25 - 50 mN/m in a solution containing 0.2 mass% of the polymer in a cement supernatant.
  • the polymer When the surface tension falls in this range, the polymer satisfy fullypracticability on a commercial scale and can effectively repress the shrinkage of cement in a cured state.
  • this polymer When this polymer is used on such a structure as steel reinforcement which induces no change of shape with time, therefore, any strain would not induced between itself and the cured cement product and thus there would be no problems as of cracking.
  • the surface tension of the polymer exceeds 50 mN/m, sufficient shrinkage-reducing effects cannot be attained. If such a polymer is used in steel reinforcement, for example, the cured cement product would shrink, to induce strain between the steel reinforcement and the cured cement product, and eventually entail the phenomenon of cracking.
  • the surface tension of the polymer in a solution containing 0.2 mass% of the polymer in a cement supernatant is preferably in the range of 25 - 46 mN/m, more preferably in the range of 25 - - 42 mN/m, and particularly preferably in the range of 25 - 38 mN/m.
  • the "surface tension in a solution containing 0.2 mass% of a polymer in a cement supernatant" is referredto as a value determined in accordance with the following procedure under the following conditions .
  • Instrument for determination Made by BYK-Chemie and sold under the Product Name of "Dynometer.” Ring: Made of platinum in a diameter of 19.5 mm Standard solution: Purified water, 72.8 mN/m (20°C) Table speed: 1.5 mm/min. Measuring temperature: 20°C ⁇ Procedure of determination> In a glass beaker having an inner volume of 300 ml and holding a stirrer chip 39 mm in length, 200 mass parts of deionized water at 25°C is placed and kept stirred with a magnetic stirrer. Then, 100 mass parts of ordinary portland cement made by Taiheiyo Cement K.K.
  • an aqueous solution having a solid content of 5 mass% is prepared by adding a deionized water at 25°C to a drying shrinkage-reducing agent of this invention or a copolymer for comparison.
  • a drying shrinkage-reducing agent of this invention or a copolymer for comparison is added 5 mass parts of the aqueous solution containing the drying shrinkage-reducing agent of this invention or the copolymer for comparison and 120 mass parts of the aforementioned cement supernatant together and thoroughly mixing them.
  • the aqueous 0.2 mass% sample solution is prepared. This aqueous sample solution is placed in a container, sealedwithnitrogen therein, tightly stoppered, and adjusted to 20°C.
  • the platinum ring in a thoroughly cleaned state is mounted on the Dynometer and submerged to a depth of 3 mm in the standard solution (purified water) adjusted in advance at 20°C.
  • the table holding this standard solution is lowered at a speed of 1.5 mm/min.
  • the point at which the reading of the Dynometer reaches the maximum is calibrated as the surface tension of water.
  • the thoroughly cleaned platinum ring is submerged to a depth of 3 mm in the sample solution adjusted in advance at 20°C and the table holding the aqueous solution thereon is lowered at a speed of 1.5 mm/min.
  • R 1 , R 2 , and R 3 stand for a hydrogen atom, a methyl group, or a -(CH 2 ) p COOX group, preferably a hydrogen atom or a methyl group. In this case, R 1 , R 2 , and R 3 may be identical or different from each other.
  • (CH 2 ) p COOX X stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group (-NH 2 ) , an organic amine group, or a hydrocarbon group.
  • X is a divalent metal, it assumes the form of an anhydride with two -COO- ' s .
  • organic amine group groups from such primary amines as methyl amine, ethyl amine, propyl amine, n-butyl amine, sec-butyl amine, tert-butyl amine, cyclohexyl amine, benzyl amine, and phenyl amine; groups from such secondary amines as dimethyl amine, diethyl amine, dipropyl amine, dibutyl amine, diisobutyl amine, di-sec-butyl amine, di-tert-butyl amine, dicyclohexyl amine, dibenzyl amine, and diphenyl amine; groups from such tertiary amines as trimethyl amine, triethyl amine, tripropyl amine, tributyl amine, tricyclohexyl amine, tribenzyl amine, and triphenyl amine; andgroups fromsuch alkanol amines
  • the hydrocarbon group is a hydrocarbon group preferably of 1 - 30 carbon atoms, more preferably of 1 - 20 carbon atoms, and particularly preferably of 1 - 12 carbon atoms .
  • hydrocarbon group of 1 - 30 carbon atoms linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, isooctyl, 2, 3, 5-trimethylhexyl, 4-ethyl-5-methyloctyl, and 2-ethylhexyl, tetradecyl, octadecyl, andisocyl; cyclic alkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl;
  • X preferably stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group, or an organic amine group and particularly a hydrogen atom, sodium, or calcium.
  • p is an integer of 0 - 2, preferably 0 or 1, and particularly 0.
  • R 4 stands for a hydrocarbon group of 4 - 30 carbon atoms. If the number of carbon atoms of R 4 is not more than 3, the shortage would not result in attaining drying shrinkage-reducing properties aimed at. Conversely, if this number exceeds 31, the overage wouldresult in disrupting the balance between hydrophilicity and hydrophobicity of the polymer. Thus, the carbon atom number preferably falls in the range of 4 - 30.
  • the carbon atomnumber of R 4 is preferably in the range of 4 - 30, more preferably in the range of 4 - 18, and still more preferably in the range of 4 - 12, and most preferably in the range of 5 - 12.
  • hydrocarbon group linear andbranched alkyl groups such as butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, isooctyl, 2, 3, 5-trimethylhexyl, 4-ethyl-5-methyloctyl and 2-ethylhexyl, tetradecyl, octadecyl, andicosyl; cyclic alkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and
  • alkyl groups such as butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, isooctyl, 2, 3, 5-trimethylhexyl,
  • ester compounds of a monool of 4 - 30 carbon atoms such as butanol, isobutanol, sec-butanol, tert-butanol, 1-pentanol, 1-hexanol, octanol, 1-ethyl-l-hexanol, nonyl alcohol, lauryl alcohol, cetyl alcohol, and stearyl alcohol; unsaturated aliphatic alcohols of 4 - 30 carbon atoms such as oleyl alcohol, alicyclic alcohols of 4 - 30 carbon atoms such as cyclohexanol, and aromatic alcohols of 6 - 30 carbon atoms such as phenol, phenylmethanol (benzyl alcohol)
  • ester compounds of the aforementioned alcohol of 4 - 30 carbon atoms with such an unsaturated monocarboxylic acid as (meth) acrylic acid and crotonic acid may be favorably usedas themonomer (a) fromtheviewpoint of the copolymerizing property with a monomer which introduces the structural unit (II) which will be described specifically herein below.
  • the monomer (a) which has the structural unit (I) of the formula (1) wherein at least one of R 1 , R 2 , ' and R 3 stands for a - (CH 2 ) p COOX group andX stands for a hydrogen atom, a suitvalent metal, a divlent metal, an ammonium group, or an organic amine group, such unsaturated monocarboxylic acid type monomers as acrylic acid, methacrylic acid, crotonic acid, andmetal salts, ammonium salts, and amine salts thereof may be cited.
  • the unsaturated dicarboxylic acid type monomer -maleic acid, itaconic acid, citraconic acid, fumaric acid, ormetal salts, ammonium salts, and amine salts thereof may be cited.
  • the anhydride thereof maleic anhydride, itaconic anhydride, and citraconicanhydridemaybe cited.
  • the unsaturated monocarb ' ocylic acid type monomers prove favorable and (meth) acrylic acid and salts thereofprove particularly favorable.
  • Themonomers (a) cited above may be used either singly or in the form of a mixture of two or more members.
  • various alkyl (meth) acrylates such as butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, 1-pentyl (meth) acrylate, 1-hexyl (meth) acrylate, 1-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, and benzyl (meth) acrylate; various alkyl maleates such as (di)propylmaleate, (di) butylmaleate, and (di) -2-ethylhexyl maleate; and various alkyl fumarates such as (
  • these monomers (a) or the structural units (I) may be used either singly or in the form of a mixture of two or more members.
  • R 5 , R ⁇ , andR 7 stand for a hydrogen atom or a methyl group and preferably at least either of R 5 • and R 6 stands for a hydrogen atom.
  • R 5 , R 6 , and R 7 may be identical or different from each other.
  • s is an integer of 0 - 2, preferably 0 or 1, and more preferably 0.
  • R 8 0 stands for an oxyalkylene group of 2 - 18 carbon atoms, preferably an oxyalkylene group of 2 - 8 carbon atoms, and more preferably an oxyalkylene group of 2 - 4 carbon atoms.
  • oxyalkylene group oxyethylene group, oxypropylene group, oxybutylene group, oxyisobutylene group, oxy-1-butene group, oxy-2-butene group, andoxystyrene group may be cited.
  • Oxyethylene group, oxypropylene group, and oxybutylene group are preferable, and oxyethylene group and oxypropylene group are more preferable .
  • the oxyalkylene groups may be present either singly or in the form of a mixture of two or more members in one structural unit.
  • the form of their addition may be in any such additions as random addition, block addition, and alternating addition.
  • the oxyalkylene group preferably contains an oxyethylene group as an essential component for the purpose of securing the balance between hydrophilicity and hydrophobicity. More preferably, the oxyethylene group accounts for not less than 50 mol% of the oxyalkylene group.
  • u stands for an average addition mol number of the oxyalkylene group (R 8 0) , and is in the range of 1 - 300. If u exceeds 300, the produced polymer would manifest dispersibility, preclude its own incorporation in a necessary amount, and render difficult the acquisition drying shrinkage-reducing properties aimed at.
  • u is preferably in the range of 1 - 150, 1 - 100, 1 - 80, 1 - 50, and 1 - 30 in this order.
  • R 9 stands for a hydrogen atom or a hydrocarbon group of 1 - 30 carbon atoms.
  • it stands for a hydrogen atom or a hydrocarbon group of 1 - 20 carbon atoms. More preferably, it stands for a hydrogen atom or a hydrocarbon group of 1 - 18 carbon atoms.
  • hydrocarbon group such as methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, isooctyl group, 2,3, 5-trimethylhexyl group, 4-ethyl-5-methyloctyl group and 2-ethylhexyl group, tetradecyl group, octadecyl group, and icosyl group; cyclic alkyl groups such as cycl
  • ester compounds of (meth) acrylic acid or crotonic acid and corresponding alkoxypolyalkylene glycol which answer the formula (2) on the condition that R 9 happen to be a hydrocarbon group prove particularly advantageous .
  • the monomers (b) mentioned above may be used either singly or in the form of a mixture of two or more members .
  • various alkoxypolyethylene glycol mono (meth) acrylates such as hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, methoxypolyethylene glycol acrylate, ethoxypolyethylene glycol acrylate, 1-propoxypolyethylene glycol acrylate, 2-propoxypoly-ethylene glycol acrylate, 1-butoxypolyethylene glycol acrylate, 2-butoxypolyethylene glycol acrylate, 2-methyl-l-propoxypolyethylene glycol acrylate, 2-methyl-2-propoxypolyethyleneglycol acrylate, 1-pentyloxypolyethylene glycol acrylate, 1-hexyloxypolyethylene glycol acrylate, cyclohexyloxypolyethylene glycol acrylate, 1-octyloxypolyethylene glycol acrylate, 2-ethyl-l-hexyloxypolyethylene glycol acrylate, 2-ethyl-
  • 1-butoxypolyethylenepolybutylene glycolmono (meth) acrylate, and esters of alcohol having at least two alkylene oxides added with (meth) acrylic acid such as esters of (meth) allyl alcohol having ethylene oxide and propylene oxide added with (meth) acrylic acid, and esters of crotyl alcohol having ethylene oxide, propylene oxide and butylene oxide added with (meth) acrylic acidmay be cited.
  • these monomers (b) or structural units (Il-a) may be used either singly or in the form of a combination of two or more members .
  • R 10 , R 11 and R 12 stand for a hydrogen atom or a methyl group and preferably at least either of R 10 or R 11 stands for a hydrogen atom.
  • R 10 , R 11 , and R 12 may be identical or different from each other, x is an integer of 0 - 2, preferably 0 or 1, and more preferably 0.
  • R 13 0 stands for an oxyalkylene group of 2 - 18 carbon atoms, preferably an oxyalkylene group carbon atomsof 2-8 carbon atoms, andmore preferably an oxyalkylene group of 2 - 4 carbon atoms.
  • the oxyalkylene group in this case is as defined for R 8 0 in the formula (2) .
  • the oxyalkylene groups may be present either singly or in the form of a mixture of two or more members in one structural unit.
  • the form of their addition maybe inany such additions as randomaddition, blockaddition, and alternating addition.
  • the oxyalkylene group preferably contains an oxyethylene group as an essential component for the purpose of securing the balance between hydrophilicity and hydrophobicity.
  • the oxyethylene group accounts for not less than 50 mol% of the oxyalkylene group .
  • y stands for anaverage additionmol number of the oxyalkylene group (R 13 0) and is in the range of 1 - 300. If y exceeds 300, the produced polymer would manifest dispersibility, preclude its own incorporation in a necessary amount, and render difficult the acquisition drying shrinkage-reducing properties aimed at. Further, when y exceeds 300, the excess wouldresult in exalting air entraining property, rendering difficult the adjustment of the air content, and inducing degradation of strength and deterioration of the resistance to freezing and melting.
  • y is preferably in the range of 1 - 150, 1 - 100, 1 - 80, 1 - 50, and 1 - 30 in this order.
  • R 14 stands for a hydrogen atom or a hydrocarbon group of 1 - 30 carbon atoms, preferably a hydrogen atom or a hydrocarbon group of 1 - 20 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group of 1 - 18 carbon atoms, and particularly preferably a hydrocarbon group of 1 - 12 carbon atoms. Since the substituent "R 14 " in the formula (3) is as defined for the substituent "R 9 " in the formula (2) , the description thereof will be omitted herein.
  • the monomer which introduces the structural unit (Il-b) into the polymer in this invention include the adducts of alkylene oxides of 2 - 18 carbon atoms to such alcohols as vinyl alcohol and isoprene alcohol, for example.
  • the monomers (c) mentioned above may be used either singly or in the form of a mixture of two or more members.
  • monomer (c) As typical examples of the monomer (c) , (poly) ethylene glycol-3-methyl-3-butenyl ether, (poly) propylene glycol-3-methyl-3-butenyl ether, (poly) butylene glycol-3-methyl-3-butenyl ether, (poly) ethylene glycol (poly) propylene glycol-3-methyl-3-butenyl ether, and (poly) ethylene glycol (poly) butylene glycol-3-methyl-3-butenyl ether may be cited. In this case, these monomers (c) or structural units (Il-b) may be used either singly or in the form of a combination of two or more members .
  • R 15 , R 16 , and R 17 stand for a hydrogen atom, a methyl group, or a -(CH 2 ) q COOZ' group.
  • R 15 , R 16 , and R 17 may be identical or different from each other.
  • Z' stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group, or an organic amine group.
  • q is an integer of 0 - 2, preferably 0 or 1, and particularly 0.
  • Z stands for a hydrogen atom, amonovalentmetal, a divalent metal, an ammonium group, or an organic amino group.
  • substituents "Z" and “Z'” are as defined for the substituent "X" in the formula (1) except they do not stand for a hydrocarbon group.
  • the COOZ' groups may be identical or different from each other.
  • the groups COOZ' and COOZ are present in the total number of not less than 2, two of them may form an anhydride .
  • such unsaturated monocarboxylic acid type monomers as acrylic acid, methacrylic aciid, crotonic acid, and metal salts, ammonium salts, and amine salts thereof may be cited.
  • unsaturateddicarboxylic acid type monomers maleic acid-, itaconic acid, citraconic acid, fumaric acid, andmetal salts, ammonium salts, and amine salts thereof may be cited.
  • anhydrides thereof maleic anhydride, itaconic anhydride, and citraconic anhydride may be cited.
  • unsaturated monocarboxylic acid type monomers wherein R 15 , R 16 , and R 17 independently stand for a hydrogen atom or a methyl group prove advantageous and (meth) acrylic acids and salts thereofprove particularly favorable .
  • these monomers (d) or structural units (III) may be used either singly or in the form of a combination of two or more members .
  • the polymer according to this invention contains a structural unit (I) and a structural unit (Il-a) and/or a structural unit (Il-b) as essential structural units and contains a structural unit (III) in a proportion in the range of 0 - 30 mass% based on the total mass of the polymer.
  • each the structural units (I) , (Il-a) , and (Il-b) and the structural unit (III) may be either singly or in the form of a combination of two or more members.
  • the structural unit (I), the structural unit (Il-a) , the structural unit (Il-b) , and the structural unit (III) may be independently in a blocked form or a random form.
  • the polymer according to this invention may contain at least one other structural unit (occasionally referred to briefly as “structural unit (IV) ”) . Even in this case, these structural units may be present in a blocked form or a random form.
  • the monomers which introduces the other structural unit (IV) to the polymer (occasionally referred to briefly as “monomer (e) " hereinafter) include monomers which are copolymerizable with the other monomer component, for example.
  • these monomers (e) or structural units (IV) originating in the monomers (e) may be used either singly or in the form of a combination of two or more members .
  • the method for producing the polymer according to this invention does not need to be particularly restricted. Any of the known methods available for polymerization may be adopted. Generally, the monomer component mentioned above may be polymerized by the use of a polymerization initiator. The method for polymerizing the monomer components does not need to be particularly restricted. Any of the known method available for polymerization may be used similarly or as modified.
  • the polymerization may be accomplished by polymerization in a solvent or by bulk polymerization, for example. The polymerization in a solvent may be carried out batchwise or continuously.
  • the solvent ' which can be used in this case, water; lower alcohols such as methyl alcohol, ethyl alcohol, and 2-propanol; aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane, and n-hexane; ester compounds such as ethyl acetate; and ketone compounds such as acetone andmethylethyl ketone may be cited.
  • lower alcohols such as methyl alcohol, ethyl alcohol, and 2-propanol
  • aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane, and n-hexane
  • ester compounds such as ethyl acetate
  • ketone compounds such as acetone andmethylethyl ketone
  • the polymerization initiator to be used when the polymerization is performed in an aqueous medium does not need to be particularly restricted. Any of the known polymerization initiators may be used. Such water-soluble polymerization initiators as ammonium, a persulfate of an alkali metal, or hydrogen peroxide are available.
  • the polymerization initiator may be used in combination with such a promoter as sodium hydrogen sulfite, Mohr' s salt, ascorbic acid (the salt thereof), or Rongalite.
  • a promoter as sodium hydrogen sulfite, Mohr' s salt, ascorbic acid (the salt thereof), or Rongalite.
  • the polymerization initiator to be used when the polymerization is performed in a lower alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, an ester compound, or a ketone compound as a solvent does not need to be particularly restricted. Any of knownpolymerization initiators which are available may be used.
  • peroxides such as benzoyl peroxide and lauroyl peroxide; hydroperoxides such as cumene hydroperoxide; and azo compounds such as azobisisobutylonitrile, for example, can be used as the polymerization initiator.
  • the polymerization initiator may be used in combination with such a promoter as an amine compound.
  • a proper combination may be selected from various possible combinations including the use of the polymerization initiators or the combined use of the polymerization initiators and the promoters.
  • the amount of the polymerization initiator to be added does not need to be particularly restricted but may equal the amount to be used in any of the known methods of polymerization.
  • the conditions for the polymerization do not need to be particularly restricted but may equal those used in any of the known methods of polymerization.
  • the polymerization temperature for example, can be suitably decided depending on the kind of solvent and polymerization initiator to be used. Generally, it is in the range of 0 - 120°C.
  • the method to be used therefor, the kind and the amount of the polymerization initiator tobe used, andthe conditions for thepolymerization do not need to be particularly restricted but may be selected from those of known methods.
  • the polymerization initiators which are usable include peroxides such as benzoyl peroxide and lauroyl peroxide; hydroperoxides such as cumene hydroperoxide; and azo compounds such as azobisisobutylonitrile, for example.
  • the bulk polymerization may be carried out at a temperature in the range of 50 - 200°C.
  • hypophosphorous acid (salt) or a thiol type chain transfer agent additionally.
  • the thiol type chain transfer agent to be used in this case is represented by the formula: HS-R 18 -E g (wherein R 18 stands for an alkyl group of 1 - 2 carbon atoms and E stands for a -OH, -COOM, -COOR 19 , or S0 3 M, and M stands for a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group, or an organic amine group, R 19 stands for an alkyl group of 1 - 10 carbon atoms, and g is an integer of 1 - 2) .
  • thiol type chain transfer agent mercapto ethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate, and octyl 3-mercaptopropionate may be cited.
  • chain transfer agents may be used either singly or in the form of a mixture of two or more members. Further, for the adjustment of the molecular weight of the polymer, it is effective to use as the monomer (e) a monomer such as (meth) allyl sulfonic acid (the salt thereof) having a high chain transferring ability.
  • the polymer which is obtained as described above may be used in its unmodified formin the drying shrinkage-reducing agent, or alternativelymaybe handled in the formof an aqueous solution containing no organic solvent.
  • the polymer may be further neutralized with an alkaline substance such as inorganic substances including hydroxide, chloride, or carbonate of a monovalent metal and a divalent metal; ammonia; and an organic amine (preferably the hydroxide of a monovalent metal like sodium hydroxide or potassium hydroxide) and used in the form of a polymer salt in the drying shrinkage-reducing agent.
  • the polymer according to this invention contains the structural unit (I) as an essential structural unit.
  • the proportion of the structural unit (I) to be introduced into the polymer is particularly critical from the viewpoint of effectively repressing the drying shrinkage because the introduction of the hydrophobic group of R 4 in the structural unit (I) serves to lower the interfacial tension between a cured cement product and water and to decrease the tensile stress of water which forms the cause for drying shrinkage.
  • the proportion of the structural unit (I) is preferably in the range of 7 - 99 mass%, 7 -70 mass%, 10 - 60 mass%, 15 - 60 mass%, and 15 - 50 mass% in this order.
  • the proportion of the structural unit (I) falls short of the lower limit, the shortage would possibly result in preventing the hydrophobic group from being introduced in a sufficient amount into the polymer and consequently preventing the function of lowering the tensile stress from being manifested fully satisfactorily, and impairing the polymer's effect in repressing the drying shrinkage.
  • this proportion of the structural unit (I) exceeds the upper limit, the excess would possibly result in suffering the polymer to incorporate hydrophobic groups excessively therein, rendering it insoluble in water, preventing it from assuming the form of an aqueous solution and from lowering the interfacial tension between a cured cement product and water, and precluding the acquisition of fully satisfactory drying shrinkage reducing effects.
  • the polymer according to this invention preferably contains the structural unit (Il-a) and/or the structural unit (Il-b) as essential components in addition to the structural unit (I), and contains the structural unit (III) in a proportion in the range of 0 - 30 mass% based on the total mass of the polymer, and occasionally may contain the structural unit (IV) .
  • the proportion of the structural unit (I) in the polymer in this case is the same as the proportion mentioned above.
  • the ratios of the other structural units (Il-a), (Il-b) , (III), and (IV) do not need to be particularly restricted but are only required to be capable of manifesting outstanding effects for reducing and repressing the shrinkage • of a cured cement product due to drying without manifesting any dispersibility.
  • the proportion of the structural- unit (Il-a) is preferably in the range of 1 - 90 mass%, more preferably in the range of 5 - 80 mass%, based on the total mass of the polymer; the proportion of the structural unit (Il-b) is preferably in the range of 1 - 90 mass%, more- preferably in the range of 5 - 80 mass%, based on the total mass of the polymer; the proportion of the structural unit (III) is in the range of 0 - 30 mass% based on the total mass of the polymer; and the proportion of the structural unit (IV) is preferably in the range of 0 - 30 mass%, more preferably in the range of 0 - 20 mass%, based on the total mass of the polymer.
  • the structural unit (III) is present in a proportion in the range of 0 - 30 mass% based on the total mass of the polymer. In this case, if the proportion of the structural unit (III) exceeds 30 mass%, the excess would possibly result in suffering the polymer to incorporate an acid excessively and consequently compelling the polymer to be adsorbed on cement to manifest dispersibility. Further, since the hardening time of a cement product is elongated as the amount of the structural unit (III) to be introduced is increased, the structural unit (III) is preferably present in the smallest possible amount in the polymer.
  • the proportion of the structural unit (III) is preferably in the range of 0 - 20 mass%, more preferably in the range of 0 - 15 mass%, still more preferably in the range of 0 - 10 mass%, and most preferably in the range of 0 - 5 mass%, based on the total mass of the polymer.
  • the total of the proportions of the structural units (I) , (Il-a) , (Il-b) , (III), and (IV) isl00mass%.
  • the polymer according to this invention may be produced by directly esterifying an alkoxypolyalkylene glycol in at least part of the carboxyl group of the copolymer obtained by copolymerizing the monomer component containing the unsaturatedmonocarboxylic acidtype monomer such as acrylic acid, methacrylic acid, or crotonic acid and the monomer (such as, for example, the monomer (a) ) providing the structural unit -(I) .
  • the monomer component containing the unsaturatedmonocarboxylic acidtype monomer such as acrylic acid, methacrylic acid, or crotonic acid
  • the monomer such as, for example, the monomer (a)
  • the weight average molecular weight of the polymer according to this invention falls properly in the range of 500 - 500, 000, preferably in the range of 500 - 300, 000, more preferably in the range of 500 - 200, 000, still more preferably in the range of 500 - 100,000, and particularly preferably in the range of 500 - 80,000, as expressed in terms of polystyrene determined by the gel permeation chromatography (referred to hereinafter as "GPC") .
  • GPC gel permeation chromatography
  • drying shrinkage-reducing agent of this invention can be applied to a wide range of applications including hydraulic materials, it can be used particularly advantageously for hydraulic materials.
  • the drying shrinkage-reducing agent of this invention may be formed of one kind of polymer mentioned above or may be formed of two or more kinds of polymers cited above. Further, by combining the drying shrinkage-reducing agent of this invention and a dispersing agent, the dispersibility and the drying shrinkage-reducing properties can be easily adjusted depending on the purpose.
  • the second aspect of this invention therefore, relates to a shrinkage-reducing composition comprising at least one kind of the drying shrinkage-reducing agent of this invention and a dispersing agent.
  • drying shrinkage-reducing agents may be used either singly or in the form of a mixture of two or more members.
  • the dispersing agent which can be used in this invention does not need to be particularly restricted. Any of the known dispersing agents may be used.
  • the known dispersing agents include copolymers of alkenyl ether type monomers resulting fromadding ethylene oxide to such specific unsaturated alcohol as 3-methyl-3-buten-l-ol, unsaturated carboxylic acid type monomers, and monomers copolymerizable with these monomers, or the salts thereof, as disclosed in JP-A SHO 62-68806, various sulfonic acid type dispersing agents having a sulfonic group in the molecular unit thereof, and various polycarboxylic acid type dispersing agents having a polyoxyalkylene chain and a carboxyl group in the molecular unitthereof, for example.
  • lignin sulfonates As typical examples ofthe sulfonic acid type dispersing agent, lignin sulfonates; polyol derivatives; naphthalene sulfonic acid formalin condensates; melamine sulfonic acid formalin condensates; polystyrene sulfonates; and aminosulfonic acid type dispersing agents such as aminoaryl sulfonic acid-phenol formaldehyde condensates (see JP-A HEI 1-113419) may be cited.
  • aminosulfonic acid type dispersing agents such as aminoaryl sulfonic acid-phenol formaldehyde condensates (see JP-A HEI 1-113419) may be cited.
  • Polycarboxylic acid type dispersing agents (A) comprising as essential structural units the structural unit (Il-a) represented by the formula (2) and the structural unit (III)
  • polcarboxylic acid type dispersing agents (B) comprising as essential structural units the structural unit (Il-b) represented by the formula (3) and the structural unit
  • hydrophilic graft polymers obtained by the graft polymerization of an unsaturated carboxylic acid monomer to a polyether compound as described in JP-A-Hei 7-53645,
  • JP-A-Hei 8-208769 and JP-A-Hei 8-208770 may be also advantageously used as the polycarboxylic acid type dispersing agent.
  • the polycarboxylic acid type dispersing agents (A) and (B) may be preferably used.
  • the polycarboxylic acid type dispersing agent is one of the above-mentioned polycarboxylic acid type dispersing agents (A) and (B) .
  • the polycarboxylic acid type dispersing agents (A) and polycarboxylic acid type dispersing agents (B) may be used either singly or in the form of a mixture of two or more members, respectively.
  • the polycarboxylic acid type dispersing agent (A) is a polymer comprising, as essential structural units, the structural unit (Il-a) represented by the formula (2) and the structural unit (III) . It may further comprise another structural unit derived fromother copolymerizablemonomer (e) . Each of these structural units in the polycarboxylic acid type dispersing agent (A) may comprise one single species or two or more species .
  • the proportion of the structural unit (Il-a) and structural unit (III) (structural unit (Il-a) /structural unit (III) ; % by mass) in the above polycarboxylic acid type dispersing agent (A) is preferably 1 to 99/99 to 1.
  • the total content (%bymass) ofthe structuralunit (Il-a) andstructural unit (III) in the polycarboxylic acid type dispersing agent (A) is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, based on the total mass of the polycarboxylic acid type dispersing agent (A) .
  • the polycarboxylic acid type dispersing agent (B) is a polymer comprising, as essential structural units, the structural unit (Il-b) represented by the formula (3) and the structural unit (III) . It may further comprise another structural unit derived fromother copolymerizablemonomer (e) . These structural units in the polycarboxylic acid type dispersing agent (B) each may comprise one single species or two or more species.
  • each the structural unit (Il-b) and the structural unit (III) preferably accounts for at least 1% by mass of all structural units, and the proportion of the structural unit (Il-b) is preferably not more than 50 mol % of all the structural units. If the proportion of the structural unit (Il-b) is less than 1% by mass, the content of the oxyalkylene group (s) of the unsaturated (poly) alkylene glycol ether monomer contained in the polycarboxylic acid type dispersing agent (B) would be unduly low.
  • the proportion of the structural unit (III) is less than 1% by mass, the content of the carboxyl groups of the unsaturated monocarboxylic acid monomer contained in the polycarboxylic acid type dispersing agent (B) would be unduly low. In either case, the dispersing- ability of the produced polycarboxylic acid type dispersing agent (B) would tend to decrease. Further, since the unsaturated (poly) alkylene glycol ether monomer has low polymerizability, it is preferred that the proportion of the structural unit (Il-b) be not more than 50 mol % of all the structural units so that the polycarboxylic acid type dispersing agent (B) can be. obtained with excellent dispersibility in a high yield.
  • the total proportion (% by mass) of the structural units (Il-b) and (III) in the polycarboxylic acid type dispersing agent (B) may be preferably 50 to 100% by mass, more preferably 70 to 100% by mass, based on the total mss of the polycarboxylic acid type dispersing agent (B) .
  • a commercially available cement dispersing agent can be used.
  • Pozzolith No. 70 lignin sulfonic acid compound polyol complex type dispersing agent, made by
  • Pozzolith Bussan K.K. Pozzolith Bussan K.K.
  • FC-900 polycarboxylic acid type dispersing agent, made by Nippon Shokubai Co. Ltd.
  • the known cement dispersing agents mentioned above may be used either singly or in the form of a mixture of two or more members .
  • the mass ratios of the drying shrinkage-reducing agent and the dispersing agent to be formulated do not need to be particularly restricted but may be varied with the kinds of drying shrinkage-reducing agent and cement dispersing agent, the mixing ratio thereof, and the conditions of testing.
  • the ratio falls preferably in the range of 99.5 : 0.5-0.5 : 99.5, more preferably in the range of 99 : 1 - 10 : 90, and particularly preferably in the range of 98 : 2 - 20 : 80.
  • the ratio of the drying shrinkage-reducing agent exceeds 99.5 mass% of the whole • composition, the excess would be at a disadvantage in decreasing the ratio of the dispersing agent, unduly lowering the fluidity, and inducing inferior packing.
  • the ratio of the drying shrinkage-reducing agent falls short of 0.5 mass% of the whole composition, the shortage would possibly result in excessively decreasing the amount of the drying shrinkage-reducing agent- and failing to decrease the drying shrinkage of the concrete member satisfactorily.
  • the drying shrinkage-reducing agent of this invention may be used in the form of an aqueous solution, or in the formof a powder preparedbyneutralizing it with the hydroxide of a divalent metal such as calcium or magnesium to give a polyvalent metal salt thereof and drying the salt, or by depositing the polymer or salt on an inorganic powder such as a fine silica based powder and drying the depositedproduct .
  • the drying shrinkage-reducing agent of this invention can be used in various hydraulic materials, namely in cement and other hydraulicmaterials then cement, for example gypsum.
  • Preferred examples of the hydraulic composition comprising a hydraulicmaterial, water and the drying shrinkage-reducing agent of this invention, and optionally a fine aggregate (e.g.
  • shrinkage-reducing compositions in which cement is used as the hydraulic material are in commonest use.
  • Such a shrinkage-reducing composition comprises the drying shrinkage-reducing agent of this invention, cement and water as essential constituents.
  • Such a shrinkage-reducing composition is also involved in the scope of this invention.
  • portland cements ordinary, •high-early-strength, ultra high-early-strength, moderate heat, sulfate resistant, and low alkali grades thereof
  • various blended cements blast furnace slag cement, silica cement, fly ash cement
  • white portland cement calcium-aluminate cement
  • ultra rapid hardening cement one clinker ultra rapid hardening cement, two clinker ultra rapid hardening cement, magnesium phosphate cement
  • grouting cement oil-well cement
  • lower calorific value cement lower calorific value blast furnace slag cement, fly ash-mixed lower calorific value blast furnace slag cement, high belite cement
  • ultrahigh strength cement cement-basedhardeningmaterials
  • economical cement cement produced by using at least one of municipal refuse incineproportionn ash and sewage sludge incineproportionn ash as a material
  • Fine powders such as blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder and limestone powder, and gypsum may further be added.
  • aggregate gravel, crushed stone, water granulated blast furnace slag, recycled concrete aggregate and, further, fireproof aggregates such as silica stone-based, clay-based, zircon-based, high alumina, silicon carbide-based, graphite-based, chrome-based, chrome-magnesite, and magnesia-based ones can be used.
  • the unit water amount is preferably set to a level in the range of 100 to 185 kg/m 3 ; the amount of cement used is preferably set to a level in the range of 250 to 800 kg/m 3 , and the water/cement ratio (mass ratio) is preferably set to a level in the range of 0.1 to 0.7. More preferably, the unit water amount is in the range of 120 to 175 kg/m 3 , the amount of cement used is in the range of 270 to 800 kg/m 3 , and the water/cement ratio (mass ratio) is in the range of 0.2 to 0.65.
  • the shrinkage-reducing composition of this invention can be used in such a wide range as from poor to rich mixtures, and also can be applied both to high strength concrete with a high unit cement amount and to poor concrete with a unit cement amount of not more than 300 kg/m 3 .
  • the amount of the drying shrinkage-reducing agent of this invention formulated in the shrinkage-reducing composition of this invention is preferably in the range of 0.001 to 20.0% by mass based on the mass of cement when it is used inmortar or concrete, for instance, in which hydraulic cement is used. If the amount is lower than 0.001% by mass, the obtained shrinkage-reducing composition would manifest unduly low shrinkage reducing ability.
  • the amount of the drying shrinkage-reducing agent to be formulated is more preferably in the range of 0.001 to 10.0% by mass, still more preferably 0.05 to 5.0% by mass, most preferably 0.01 to 3.0% by mass.
  • the shrinkage-reducing composition of this invention is effective in ready mixed concrete, concrete for secondary concrete products (precast concrete) , centrifugal molded concrete, vibrating compactedconcrete, steamcured concrete, concrete for spraying andthe like and, further, it is effective also in mortar and concrete species required to have high flowability, such as medium flowing concrete (concrete showing a slump value of 22 to 25 cm) , high flowing concrete (concrete showing a slump value of not less than 25 cm and a slump flow value of 50 to 70 cm) , self-filling concrete and self-leveling materials.
  • the shrinkage-reducing composition of this invention may further comprise one ormore of other known cement additives (ingredients) such as listed below under (1) to (20) :
  • Water-soluble polymeric substances unsaturated carboxylic acid polymers such as polyacrylic acid (sodium salt) , polymethacrylic acid (sodium salt) , polymaleic acid (sodium salt) , and acrylic acid-maleic acid copolymer sodium salt; nonionic cellulose ethers such as methylcellulose, ethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, carboxyethylcellulose and hydroxypropylcellulose; polysaccharide derivatives having apart or all hydrogen atoms of hydroxyl group (s) in an alkylated or hydroxyalkylated derivative of polysaccharide, such as methylcellulose, ethylcellulose, hydroxyethylcellulose and hydroxypropylcellulose substituted with a hydrophobic substituent comprising a hydrocarbon chain of 8 to
  • curdlan paramylon, pachyman, scleroglucan, rhamnalan
  • polyacrylamide polyvinyl alcohol
  • starch starchphosphoric acid ester
  • sodium alginate gelatin
  • Polymer emulsions copolymers of various vinyl monomer such as alkyl (meth) acrylates .
  • Retardants oxycarboxylic acids such as gluconic acid, glucoheptonic acid, arabonic acid, malic acid, citric acid, and inorganic or organic salts thereof such as sodium, potassium, calcium, magnesium, ammonium and triethanolamine salts; monosaccharides such as glucose, fructose, galactose, saccharose, xylose, apiose, ribose and invert sugar, oligosaccharides such as disaccharides and trisaccharides, such oligosaccharides as dextrin, polysaccharides such as dextran, and other saccharides such as molasses containing these saccharides; sugar alcohols such as sorbitol; magnesium silicofluoride; phosphoric acid and salts thereof, or borate esters; aminocarboxylic acids and salts thereof; alkali-soluble proteins; humic acid; tannic acid; phenols; polyhydric alcohols such as gly,
  • soluble calcium salts such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide and calcium iodide
  • chlorides such as iron chloride and magnesium chloride
  • sulfate salts potassium hydroxide; sodium hydroxide
  • carbonate salts thiosulfate salts
  • formic acid and formate salts such as calcium formate; alkanolamines; calcium-aluminate cement; calcium aluminosilicate, etc.
  • Mineral oil-based antifoaming agents kerosene, liquid paraffin, etc.
  • Fat- or oil-based antifoaming agents animal or vegetable oils, sesame oil, castor oil, and the alkylene oxide adducts thereof, etc.
  • Fattyacid-based antifoaming agents oleic acid, stearic acid, and the alkylene oxide adducts thereof, etc.
  • Fatty acid ester-based antifoaming agents glycerol monoricinolate, alkenylsuccinic acid derivatives, sorbitol monolaurate, sorbitol trioleate, natural waxes, etc.
  • Oxyalkylene type antifoaming agents polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts;
  • polystyrene resin such as diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylenepolyoxypropylene 2-ethylhexyl ether, and higher (C ⁇ 2 -C ⁇ 4 ) alcohol-oxyethyleneoxypropylene adducts;
  • poly) oxyalkylene (alkyl) aryl ethers such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether; acetylene ethers produced by addition polymerization of an alkylene oxide onto an acetylene alcohol such as 2, 4, 7, 9-tetramethyl-5-decyne-4, 7-diol, 2, 5-dimethyl-3-hexyne-2, 5-diol or 3-methyl-l-butyn-3-ol; (poly) oxyalkylene fatty acid esters such as diethylene glycol oleate, di
  • Alcohol-based antifoaming agents octyl alcohol, hexadecyl alcohol, 2-Ethylhexyl alcohol, acetylene alcohols, glycols, etc.
  • Amide-based antifoaming agents acrylate polyamines, etc.
  • Phosphate ester-based antifoaming agents tributyl phosphate, sodium octylphosphate, etc.
  • Metal salt-based antifoaming agents aluminumstearate, ⁇ calcium oleate, etc.
  • Silicone-based antifoaming agents diemthylsilicone oil, silicone paste, silicone emulsions, organic group-modified polysiloxanes (organosiloxanes such as dimethylpolysiloxane) , fluorosilicone oils, etc.
  • Air-entraining (AE) agents resin soaps, saturated or unsaturated fatty acids, sodium hydroxystearate, lauryl sulfate, ABSs (alkylbenzenesulfonates) , LASs (linear alkylbenzenesulfonates) , alkanesulfonates, polyoxyethylene alkyl (phenyl) ethers, polyoxyethylene alkyl (phenyl) ether sulfate esters or salts thereof, polyoxyethylene alkyl (phenyl) ether phosphate esters or salts thereof, proteinic materials, alkenylsulfosuccinates, ⁇ -olefinsulfonates, etc.
  • AE Air-entraining
  • surfactants polyalkylene oxide derivatives derived from aliphatic monohydric alcohols of 6 to 30 carbon atoms within the molecule, such as octadecyl alcohol and stearyl alcohol, alicyclic monohydric alcohols of 6 to 30 carbon atoms within the molecule, such as abietyl alcohol, monofunctional mercaptans of 6 to 30 carbon atoms within the molecule, such as dodecylmercaptan, alkylphenols of ⁇ to 30 carbon atoms within the molecule, such as nonylphenol, amines of 6 to 30 carbon atoms within the molecule, such as dodecylamine, or carboxylic acids of 6 to 30 carbon atoms within the molecule, such as lauric acid and stearic acid, by addition of not less than 10 moles of an alkylene oxide (s) such as ethylene oxide and/or propylene oxide; alkyldiphenyl ether sulfonic acid salts inwhich two sulfonic acid
  • Waterproofing agents fatty acids (salts), fatty acid esters, fats and oils, silicones, paraffins, asphalt, waxes, etc.
  • Rust preventives nitrite salts, phosphate salts, zinc oxide, etc. /
  • Cracking reducing agents polyoxyalkyl ethers etc.
  • Expansive admixtures ettringite type, coal-derived type, etc.
  • cement wetting agents, thickening agents, sepaproportionn reducing agents, flocculants, strength increasing agents, self-leveling agents, colorants, antifungal agents and the like can be used. These cement additives (ingredients) can be used in combination.
  • the following combinations 1) to 8) of constituents other than cement and water in the shrinkage-reducing composition of this invention may be mentioned as particularly preferred embodiments :
  • the mixing proportion, by mass, between the (a) drying shrinkage-reducing agent and the (b) polycarboxylic acid type dispersing agent is preferably in the range of 99.5/0.5 to 0.5/99.5, more preferably 98/2. to 20/80.
  • the proportion of the (c) oxyalkylene type antifoaming agent is preferably in the range of 0.01 to 200% by mass relative to the total mass of the (a) drying shrinkage-reducing agent and the (b) ligninsulfonic acid (salts) . 5) Combination of (a) a drying shrinkage-reducing agent of this invention, (b) a polycarboxylic acid type dispersing agent and (3) an oxyalkylene type antifoaming agent as three essential constituents.
  • the mixing proportion, by mass, between the (a) drying shrinkage-reducing agent and the (b) polycarboxylic acid type dispersing agent is preferably in the range of 99.5/0.5 to 0.5/99.5, more preferably 98/2 to 20/80.
  • the proportion of the (c) oxyalkylene type antifoaming agent is preferably in the range of 0.01 to 200% by mass relative to the total mass of the (a) drying shrinkage-reducing agent and thw (b) polycarboxylic acid type dispersing agent.
  • the mixing proportion, by mass, between the (a) drying shrinkage-reducing agent and the (b) material sepaproportionn reducing agent is preferably in the range of 10/90 to 99.99/0.01, more preferably 50/50 to 99.9/0.1.
  • Shrinkage-reducing compositions containing this combination are suited for the use as high flowing concrete, self-filling concrete and self-leveling composition.
  • a drying shrinkage-reducing agent of this invention Combination of (a) a drying shrinkage-reducing agent of this invention and (b) a retardant as two essential constituents .
  • a retardant for example, hydroxycarboxylic acids such as gluconic acid (salts) and citric acid (salts) , saccharides such as glucose, sugar alcohols such as sorbitol, and phosphonic acids such as aminotri (methylenephosphonic acid), among others.
  • hydroxycarboxylic acids such as gluconic acid (salts) and citric acid (salts) are morepreferablyused.
  • Themixingproportion, bymass, between the (a) drying shrinkage-reducing agent and the (b) retardant is preferably 50/50 to 99.9/0.1, more preferably 70/30 to 99/1. 8) Combination of (a) a drying shrinkage-reducing agent of this invention and (b) an accelerator as two essential constituents.
  • an accelerator as two essential constituents.
  • the accelerator are soluble calcium salts such as calcium chloride, calcium nitrite and calcium nitrate, chlorides such as iron chloride and magnesium chloride, thiosulfate salts, formic acid, and formate salts suchas calciumformate, among others .
  • Themixingproportion, by mass, between the (a) drying shrinkage-reducing agent and the (b) accelerator is preferably 10/90 to 99.9/0.1, more preferably 20/80 to 99/1.
  • an initiator solution composed of 1.41 parts of 2,2' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was added dropwise thereto over a period of five hours. Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization.
  • the resultant reaction solution was distilledto expel the 2-propanol andthendiluted with water so as to give the copolymer concentration 25 mass%, to obtain a polymer (1) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 13, 300.
  • Theweight averagemolecularweight was determined under the same conditions as the GPC as mentioned above.
  • an initiator solution composed of 1.41 parts of 2,2' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was added dropwise thereto over a period of five hours. Thereafter, the interior temperature ' of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization.
  • the resultant reaction solution was distilledto expel the 2-propanol andthen diluted with water so as to give the copolymer concentration 25 mass%, to obtain a polymer (2) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 13, 300.
  • Theweight averagemolecularweight was determined under the same conditions as the GPC as mentioned above.
  • an initiator solution composed of 1.41 parts of 2, 2' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was added dropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization.
  • the resultant reaction solution was distilled to expel the 2-propanol and then diluted with water so as to the copolymer concentration 25 mass%, and then neutralized with an aqueous 30% sodium hydroxide solution, to obtain a polymer (3) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 12,000.
  • an initiator solution composed of 1.41 parts of 2, 2' -azobis (2, -dimethyl valeronitrile) and 28.6 parts of 2-propanol was added dropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization.
  • the resultant reaction solution was distilled to expel the 2-propanol, diluted with water so as to give the copolymer concentration 25 mass%, and then neutralized with an aqueous 30% sodium hydroxide solution, to obtain a polymer (4) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 13,000.
  • an initiator solution composed of 1.41 parts of 2, 2' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was addeddropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization. The resultant reaction solution was distilled to expel the 2-propanol, diluted with water so as to give the copolymer concentration 25 mass%, and then neutralized with an aqueous 30% sodium hydroxide solution, to obtain the polymer (6) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 15,200.
  • an initiator solution composed of 1.41 parts of 2, 2 ' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was added dropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization. The resultant reaction solution was distilled to expel the 2-propanol, diluted with water so as to give the copolymer concentration 25 mass%, and then neutralized with an aqueous 30% sodium hydroxide solution, to obtain a polymer (7) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 12,600.
  • an initiator solution composed of 1.41 parts of 2,2' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was added dropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization. The resultant reaction solution was distilled to expel the 2-propanol, diluted with water so as to give the copolymer concentration 25 mass%, and then neutralized with an aqueous 30% sodium hydroxide solution, to obtain a polymer (8) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 13,400.
  • an initiator solution composed of 1.41 parts of 2, 2' -azobis (2, 4-dimethyl valeronitrile) and 28.6 parts of 2-propanol was addeddropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization. The resultant reaction solution was distilled to expel the 2-propanol, diluted with water so as to give the copolymer concentration 25 mass%, and then neutralized with an aqueous 30% sodium hydroxide solution, to obtain a polymer (9) of this invention formed of an aqueous copolymer solution having a weight average molecular weight of 12,000.
  • an initiator solution composed of 2.1 parts of sodium persulfate and 27.9 parts of deionizedwater was addeddropwise thereto over a period of five hours . Thereafter, the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization.
  • the resultant reaction solution was distilled to expel the 2-propanol, diluted with water so as to give the copolymer ' concentration 25 mass%, and then neutralized with an aqueous 30% sodiumhydroxide solution, to obtain a comparative polymer (1) of this invention formed of an aqueous copolymer solution havingaweight averagemolecularweight of 32, 000.
  • Theweight average molecular weight of the comparative polymer (1) was determined by the following method.
  • Eluting solution was prepared by dissolving 115.6 g of sodium acetate trihydrate in a mixed solvent of 10,999 g of water and 6,001 g of acetinitrile, adjusting the pH of the resultant solution to 6.0 with an aqueous 30% sodium hydroxide solution.
  • the interior temperature of the reaction vessel was continuously maintained at 65°C for one hour to complete the polymerization.
  • the resultant reaction solution was neutralized with an aqueous 30% sodium hydroxide solution and then distilled to expel the methanol, to obtain a comparative polymer (2) formed of an aqueous copolymer solution having a weight average molecular weight of 53,600.
  • the weight average molecular weight of the comparative polymer (2) was determined in the same manner as in Comparative Production Example 1.
  • the resultant reaction solution was distilled to expel the 2-propanol, to obtain a comparative polymer (3) formed of an aqueous copolymer solution having a weight average molecular weight of 60, 600.
  • the weight averagemolecular weight of the comparative polymer (3) was determined in the same manner as in Comparative Production Example 1.
  • Examples 1 - 9 and Comparative Examples 1 - 3 Polymers (1) - (9) produced by following the procedures ' of Production Examples 1 - 9 and comparative polymers (1) - (3) produced by following the procedures of Comparative Production Examples 1 - 3 were examined for surface tension in a solution containing 0.2 mass% of a polymer in a cement supernatant, amount of standard addition, and drying shrinkage-reducing effect. The results are shown in Table 1 below. .
  • the air content of a given mortar was adjusted, when necessary, by selecting and using a defoaming agent so as to have the amount of air entrained by themortar fall inthe range of 5.0 - 10.0 vol% .
  • a dilution preparedbyadding PozzolithNo.70 (ligninsulfonic acid compound polyol complex type dispersing agent, produced by Pozzolith Bussan K.K.) in a concentration of 0.25 wt%/C was used in place of the polymer.
  • a mortar test specimen (4 x 4 x 16 cm) for the examination of the drying shrinkage-reducing effect was prepared in accordance with JIS R 1129.
  • the retaining mold was coated in advance with silicone grease in order to obtain waterproofness and facilitate release therefrom.
  • the test specimenhadgauge plugs attached one each to the opposite ends thereof.
  • the mortar resulting from the kneading was pored into the retaining mold.
  • the mold was placed in a container, sealed tightly therein and retained at 20°C to effect initial curing.
  • Two days thereafter the cured mortar was extracted from the retaining mold, the silicone grease adhering to the mold was removed by washing with a scrubbing brush and water, and subsequently the mortar was left aging in still water at 20°C for five days ' (curing in water) .
  • a dial gauge (made by Nishinippon Shikenki K.K.) was used in accordance with JIS A 1129.
  • the test specimen cured in the still water for five days was wiped with paper towel to remove the water remaining on the surface thereof and immediately measured to determine the length thereof. The length found at this point was taken as a standard. Thereafter, the test specimen was stored in a ther o-hygrostat set at a temperature of 20°C and 60% of humidity for 28 days, during which period the length of the test specimen was measured at proper intervals.
  • the drying shrinkage-reducing effect was reported as a value of the decrease in the shrinkage at the time of addition of the polymer relative to the amount of shrinkage of the Pozzolith. This value increased in accordance as the decrease in the shrinkage grew. The value of not more than 10% was regarded that the shrinkage-reducing effect was absent..
  • Drying shrinkage-reducing effect (%) ⁇ [ (Amount of shrinkage of Pozzolith) - (Amount of shrinkage of polymer/comparative polymer) ] / (Amount of shrinkage of Pozzolith) ⁇ x 100
  • Table 1 shows that the polymers containing the structural unit (I) and having surface tension in the range of 25 - 50 mN/m could manifest significantly high drying shrinkage-reducing effect as compared with the polymers containing no structural unit (I) (comparative polymers 2 and 3) and the polymer containing the structural unit (I) but having surface tension exceeding the scopementioned above (comparative polymer 1) , indicating that the polymers according to this invention can effectively repress the shrinkage due to drying.
  • the polymers (1) - (9) of this invention containing the structural unit (I) and the structural unit (II) as essential structural units and also containing the structural unit (III) in a proportion in the range of 0 - 30 mass% based on the total mass of the ' polymer showed significantly improved drying shrinkage-reducing properties, as compared with the comparative polymer (1) which contains the structural unit (I) , structural unit (II) , and structural unit (III) as essential structural units but contains the structural unit (III) in a proportion exceeding 30 mass% based on the total mass of the polymer, indicating 'that the introduction of the structural unit (II) and a specific proportion of the structural unit (III) to the polymer resulted in imparting excellent drying shrinkage-reducing effect to the produced polymer.
  • the resultant aqueous monomer mixture solution and 184 parts of an aqueous 10% ammonium persulfate solution were independently added dropwise over a period of four hours. After the dropwise addition was completed, 46 parts of an aqueous 10% ammoniumpersulfate solution was added dropwise thereto over a period of one hour. Thereafter, the interior temperature of the reaction vessel was continuously maintainedat 80°C for one hour to complete thepolymerization.
  • the resultant reaction solution was neutralized to pH 7 by ' theuse of an aqueous sodiumhydroxide solutionat a temperature not higher than the polymerization temperature, to obtain a copolymer (PC-1) (weight average molecular weight 24,000) which was used as a polycarboxylic acid type dispersing agent (A) formedofthe aqueouspolymer solution.
  • Theweight average molecular weight of the copolymer (PC-1) was determined in the same manner as in Comparative Production Example 1.
  • the mortar flow value was determined in accordance with the method described in JIS R 5201-1997 with necessary modifications .
  • the mortar resulting from the kneading was pored into the retaining mold. Then, the mold was placed in a container, sealed tightly therein and retained at 20°C to effect initial curing. Two days thereafter, the cured mortar was extracted fromthe retaining mold, the silicone grease adhering to the mold was removed by washing with a scrubbing brush and water, and subsequently the mortar was left aging in still water at 20°C for ive days (curing in water) .
  • a dial gauge (made by Nishinippon Shikenki K.K.) was used in accordance with JIS A 1129. The test specimen cured in the still water for five days was wiped with paper towel to remove the water remaining on the surface thereof and immediately measured to determine the length thereof.
  • the length found at this point was taken as a standard. Thereafter, the test specimen was stored in a thermo-hygrostat set at a temperature of 20°C and 60% of humidity for 28 days, during which period the length of the test specimen was measured at proper intervals.
  • the drying shrinkage-reducing effect was reported as a value of the decrease in the shrinkage at the time of addition of the polymer relative to the amount of shrinkage of the standard. This value increased in accordance as the decrease in the shrinkage ' grew. The value of not more than 10% was regarded that the shrinkage-reducing effect was absent.
  • the amount of shrinkage of the standard was regarded as the amount of shrinkage of (Comparative Example 5) which used Pozzolith No.
  • Table 2 shows that by using the polymers (2) - (7) according to this invention in combination with FC-900 (polycarboxylic acid type dispersing agent), Pozzolith No. 70 (lignin sulfonic acid compound polyol complex type dispersing agent), or the copolymer PC-1 or PC-2, the dispersibility and the drying shrinkage-reducing effect can be attained to the levels as aimed at .
  • the table further shows that the Comparative examples 4 - 6 which used solely a dispersing agent exhibited insufficient drying shrinkage-reducing properties, although they manifested sufficient dispersibility (mortar flow value) .
  • the drying shrinkage-reducing agent of this invention has a composition as described above. When it is applied to ahydraulicmaterial such as cement paste, mortar, and concrete, it can manifest outstanding effects for repressing a crack. Accordingly, the drying shrinkage-reducing agent of this invention can improve the strength and durability of a cured product, exalt the safety of civil engineering and constructional structures, and-repress the cost of repair.

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  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Inorganic Chemistry (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

Agent réduisant le retrait de séchage lequel comprend un polymère contenant comme composant essentiel au moins un motif de structure (I) représenté par la formule (1) suivante : [Produit chimique 1] dans laquelle R1, R2 et R3 représentent indépendamment un atome d'hydrogène, un groupe méthyle ou un groupe -(CH2)pCOOX, dans lequel X représente un atome d'hydrogène, un métal monovalent, un métal divalent, un groupe ammonium, un groupe amine organique ou un groupe hydrocarboné et p est un nombre entier valant 0-2 ; et R4 représente un groupe hydrocarboné de 4-30 atomes de carbone, et présentant une tension de surface comprise dans l'intervalle 25-50 mN/m dans une solution contenant 0,2 % en poids du polymère dans un ciment
EP05721220A 2004-03-16 2005-03-15 Agent reduisant le retrait de sechage Withdrawn EP1725509A1 (fr)

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JP4761103B2 (ja) * 2004-03-26 2011-08-31 国立大学法人北海道大学 水硬性材料用収縮低減組成物
DE602006010296D1 (de) * 2005-09-26 2009-12-24 Nippon Catalytic Chem Ind POLYMER UND VERFAHREN ZU SEINER HERSTELLUNG und ZEMENTMischung mit Polymer
KR100950719B1 (ko) * 2005-09-27 2010-03-31 니폰 쇼쿠바이 컴파니 리미티드 신규한 중합체 및 이를 사용한 시멘트 혼화제
JP4531799B2 (ja) * 2007-10-19 2010-08-25 コンストラクション リサーチ アンド テクノロジー ゲーエムベーハー セメント添加剤
US7973110B2 (en) * 2008-06-16 2011-07-05 Construction Research & Technology Gmbh Copolymer synthesis process
US9834719B2 (en) 2010-11-30 2017-12-05 Schlumberger Technology Corporation Methods for servicing subterranean wells
US9950952B2 (en) 2010-11-30 2018-04-24 Schlumberger Technology Corporation Methods for servicing subterranean wells
JP6339819B2 (ja) * 2013-03-21 2018-06-06 株式会社日本触媒 水硬性組成物に用いる添加剤
JP6371574B2 (ja) * 2013-05-09 2018-08-08 花王株式会社 水硬性粉体用強度向上剤組成物
JP6333399B2 (ja) 2014-09-30 2018-05-30 株式会社日本触媒 水硬性材料用収縮低減剤
JP6666113B2 (ja) * 2015-10-28 2020-03-13 株式会社日本触媒 プレミックスセメント用骨材組成物
JP6666114B2 (ja) * 2015-10-28 2020-03-13 株式会社日本触媒 プレミックスセメント用セメント組成物
JP6901304B2 (ja) * 2016-03-31 2021-07-14 株式会社日本触媒 混和材料組成物
JP6847730B2 (ja) * 2016-03-31 2021-03-24 株式会社日本触媒 混和材料組成物
JP2017186243A (ja) * 2016-03-31 2017-10-12 株式会社日本触媒 水硬性材料用収縮低減剤
JP6858617B2 (ja) * 2016-03-31 2021-04-14 株式会社日本触媒 混和材料組成物
JP2017186244A (ja) * 2016-03-31 2017-10-12 株式会社日本触媒 混和材料組成物
JP2018154711A (ja) * 2017-03-16 2018-10-04 株式会社日本触媒 ポリカルボン酸系共重合体、セメント分散剤、コンクリート混和剤、およびコンクリート組成物
EP3724148A1 (fr) * 2017-12-13 2020-10-21 Knauf Gips KG Compositions de gypse présentant une résistance améliorée à la déformation permanente
CN116515036B (zh) * 2023-04-28 2023-10-24 济源市鲁泰纳米材料有限公司 一种用于包覆纳米氧化锌的聚合物材料及其制备方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE69610650T2 (de) * 1995-01-31 2001-05-03 Mbt Holding Ag Zuerich Zementdispergiermittel
DE19942301A1 (de) * 1999-09-04 2001-03-08 Basf Ag Zementzusammensetzungen, enthaltend redispergierbare Polymerisatpulver
KR100824576B1 (ko) * 2001-05-28 2008-04-23 가부시키가이샤 닛폰 쇼쿠바이 시멘트 첨가제 및 시멘트 조성물

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2005087685A1 *

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