JP6377458B2 - Shrinkage reducing agent and additive kit - Google Patents

Description

  The present invention relates to a shrinkage reducing agent and an additive kit.

  A hydraulic composition containing a hydraulic component such as cement has the property of shrinking in the process of becoming a cured product by curing with a hydration reaction with water, and if the amount of shrinkage is large, the cured product will crack. There is. In order to suppress such shrinkage of the cured body, for example, Patent Document 1 uses an alkylene oxide shrinkage reducing agent having a lower alkyl group. On the other hand, when a shrinkage reducing agent is used, it is generally said that the freeze-thaw resistance of the obtained cured product is reduced (Non-Patent Document 1).

  Incidentally, the evaluation of the amount of contraction (length change amount) is usually performed by the method prescribed in JIS. In this method, a hydraulic mortar obtained by kneading a hydraulic composition and water is placed on a mold, cured for a predetermined time, and then evaluated using a specimen (cured body) obtained by demolding. I do. In this case, the curing of the hydraulic mortar in the mold is determined to be performed at a temperature of about 20 ° C. for about 24 hours after the placement (see JIS A1129-1 etc.).

JP 2013-133261 A

“Freezing and thawing resistance of concrete using shrinkage reducing agent”, Cement and concrete papers, No. 54, P410-417, 2000

  However, according to the study by the present inventors, it has been found that the occurrence of cracks cannot be sufficiently suppressed only by suppressing the contraction after 24 hours of curing. Further examination revealed that the initial shrinkage combined with self-shrinkage and drying shrinkage that occurs within 24 hours immediately after contact with the water during the process of hardening of the hydraulic composition by hydration with water greatly increases the occurrence of cracks. I found that it contributed.

  When the initial shrinkage amount is evaluated from the above viewpoint, the shrinkage reducing agent described in Patent Document 1 has a problem that the shrinkage reduction effect is not sufficient, and further, there is a problem that the shrinkage reduction effect becomes small in a high temperature environment of 30 ° C. or higher. On the other hand, the shrinkage reduction effect of an alkylene oxide shrinkage reducing agent having a higher alkyl group tends to be greater than that of an alkylene oxide shrinkage reducing agent having a lower alkyl group. However, the alkylene oxide-based shrinkage reducing agent having a higher alkyl group is liable to generate bubbles and excessively increases the amount of air in the cured product, and thus it has been difficult to apply it to a hydraulic composition.

  The present invention has been made in view of the above circumstances, and obtains a cured body that has an excellent shrinkage reduction effect even in a high-temperature environment, and that has an appropriate amount of air and can maintain good freeze-thaw resistance. An object of the present invention is to provide a shrinkage reducing agent that can be used. Another object of the present invention is to provide an additive kit having the shrinkage reducing agent.

In one aspect, the present invention includes an alkylene oxide adduct represented by the following general formula (1), and a 1% by weight aqueous solution of the alkylene oxide adduct has a cloud point of 18 to 72 ° C. Provide a reducing agent.
RO-[(PO) _p / (EO) _q ] -H (1)
(In the formula (1), R represents an alkyl group or alkenyl group having 18 or more carbon atoms, the alkyl group or alkenyl group in R is linear or branched, PO is an oxypropylene group, EO Represents an oxyethylene group, and p and q satisfy the following formulas (A) to (C).)
1 ≦ p ≦ 20 (A)
1 ≦ q ≦ 30 (B)
10 <p + q ≦ 30 (C)

  According to the shrinkage reducing agent of the present invention, a cured body having an excellent shrinkage reducing effect even under a high temperature environment and having an appropriate amount of air can be obtained. For this reason, it becomes possible to obtain a cured body having excellent strength and further having freeze-thaw resistance.

  The alkylene oxide adduct preferably has an HLB value of more than 8 and 20 or less. When the HLB value exceeds 8, moderate water solubility tends to be obtained.

  In another aspect, the present invention provides an additive kit for a hydraulic composition. The additive kit includes the cement shrinkage reducing agent and an antifoaming agent. The additive kit having the shrinkage reducing agent and the antifoaming agent is useful for producing a hydraulic composition having a shrinkage reducing effect and a defoaming effect according to demand in a well-balanced manner.

  According to the present invention, there is provided a shrinkage reducing agent capable of obtaining a cured body having an excellent shrinkage reducing effect even in a high temperature environment and having an appropriate amount of air and capable of maintaining good freeze-thaw resistance. Can be provided. The present invention can also provide an additive kit having the shrinkage reducing agent.

It is the graph which compared the change of the length variation | change_quantity in the hydration initial stage in the high temperature environment of the hydraulic mortar obtained by the reference example 2-1 and the comparative example 2-1. It is the graph which compared the freeze-thaw resistance of the hardening body of the hydraulic mortar obtained in Reference Example 2-7 and Comparative Example 2-13. It is the schematic which shows a cloud point measuring instrument. It is the schematic which shows a shrinkage | contraction amount (length change amount) measuring apparatus, (a) is the top view, (b) is bb line of the length change amount measuring apparatus shown to (a). FIG.

  Hereinafter, a preferred embodiment of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

(Shrinkage reducing agent)
The shrinkage reducing agent according to the present embodiment is a shrinkage reducing agent for cement used together with a hydraulic component such as cement. Although the kind of hydraulic component is not specifically limited, Especially it is used suitably with Portland cement.

The shrinkage reducing agent according to this embodiment includes an alkylene oxide adduct represented by the following general formula (1).
RO-[(PO) _p / (EO) _q ] -H (1)

  In the general formula (1), R represents an alkyl group or alkenyl group having 18 or more carbon atoms. The alkyl group or alkenyl group in R is linear or branched. When the carbon number of R is 18 or more, an excellent shrinkage reduction effect can be obtained in the initial stage within 24 hours immediately after water contact. Further, from the viewpoint of handling properties, the carbon number of R is preferably 22 or less, and more preferably 20 or less. If the carbon number of R is less than 18, an excellent shrinkage reduction effect may not be obtained in a high temperature environment.

In the general formula (1), PO represents an oxypropylene group (—C ₃ H ₆ O—), EO represents an oxyethylene group (—C ₂ H ₄ O—), and [(PO) _p / (EO) _q ] Is a polyoxyalkylene group in which p oxypropylene groups (PO) and q oxyethylene groups (EO) are bonded. One end of the polyoxyalkylene group is bonded to the R (alkyl group or alkenyl group) via an ether bond, and the other end is bonded to a hydrogen atom. Hereinafter, a hydroxyl group formed by bonding a polyoxyalkylene group and a hydrogen atom may be referred to as a terminal hydroxyl group.

In the general formula (1), p is the average number of moles of oxypropylene group added in 1 mole of the alkylene oxide adduct and satisfies the following formula (A).
1 ≦ p ≦ 20 (A)
When p is 1 or more, a sufficient shrinkage reduction effect can be obtained. When p is 20 or less, the hydrophobicity of the alkylene oxide adduct does not become too strong, and a decrease in solubility in water can be suppressed. From the same viewpoint, 2 ≦ p ≦ 18 is preferable, 3 ≦ p ≦ 16 is more preferable, 4 ≦ p ≦ 15 is further preferable, and 5 ≦ p ≦ 14 is particularly preferable. preferable.

In the above general formula (1), q is the average number of moles of oxyethylene groups added in 1 mole of the alkylene oxide adduct and satisfies the following formula (B).
1 ≦ q ≦ 30 (B)
When q is 1 or more, hydrophilicity can be imparted to the alkylene oxide adduct. When q is 30 or less, the hydrophilicity of the alkylene oxide adduct does not become too strong, and the generation of bubbles can be suppressed. From the same viewpoint, 1 ≦ q ≦ 25 is preferable, 3 ≦ q ≦ 23 is more preferable, 10 ≦ q ≦ 20 is further preferable, and 11 ≦ q ≦ 17 is particularly preferable. preferable.

Moreover, p and q satisfy | fill following formula (C).
10 <p + q ≦ 30 (C)
When the sum of p and q exceeds 10, there is a tendency that a higher shrinkage reduction effect can be obtained. When the sum of p and q is 30 or less, excellent handling properties tend to be obtained. From the same viewpoint, 10 ≦ p + q ≦ 29 is preferable, 12 ≦ p + q ≦ 28 is more preferable, 13 ≦ p + q ≦ 27 is further preferable, and 14 ≦ p + q ≦ 26 is more preferable. More preferably, 15 ≦ p + q ≦ 25 is particularly preferable, and 16 ≦ p + q ≦ 21 is most preferable.

  The lower limit of q / p is preferably 0.1, more preferably 0.2, even more preferably 1.0, still more preferably 1.5, and 2.0 It is particularly preferred that On the other hand, the upper limit value of q / p is preferably 10.0, and more preferably 0.5. When q / p is 0.1 or more, the hydrophilicity and cloud point of the shrinkage reducing agent tend to increase.

  The alkylene oxide adduct may be any of random addition type, block addition type, and random / block addition type. The “random addition type” is an addition form in which oxypropylene groups and oxyethylene groups are randomly copolymerized and arranged. The “block addition type” is an addition form in which at least one block to which only one of oxypropylene group and oxyethylene group is added is arranged. The “random / block addition type” is an addition form in which the random addition type and the block addition type are mixed. The alkylene oxide adduct can have a wide range of cloud points depending on the addition form of the oxyalkylene group.

  The weight average molecular weight of the alkylene oxide adduct is not particularly limited, but is preferably 300 to 3000, more preferably 500 to 2500, still more preferably 500 to 2000, still more preferably 1000 to 2000, and particularly preferably 1000 to 1500. It is. When the weight average molecular weight is 300 or more, a higher shrinkage reduction effect tends to be obtained. When the weight average molecular weight is 3000 or less, higher handling properties tend to be obtained.

  The cloud point (hereinafter sometimes referred to as 1% cloud point) in a 1% by mass aqueous solution of the alkylene oxide adduct is 18 to 72 ° C. When the cloud point in the 1% by mass aqueous solution of the alkylene oxide adduct is 18 ° C. or higher, the solubility in water in a high temperature environment is improved, and thus high shrinkage reduction is obtained. When the 1% cloud point of the alkylene oxide adduct is 72 ° C. or lower, high handling properties (flow value) can be obtained, air entrainment can be reduced, and strength reduction of the cured product can be suppressed. From the same viewpoint, the 1% cloud point of the alkylene oxide adduct is preferably 20 to 71 ° C, more preferably 22 to 70 ° C, still more preferably 30 to 65 ° C, and more preferably 50 to It is particularly preferable that the temperature is 60 ° C.

  The alkylene oxide adduct has an HLB (Hydrophil Lipophil Balance) value of more than 8 and preferably 20 or less. When the HLB value of the alkylene oxide adduct exceeds 8, there is a tendency that moderate water solubility is obtained. From the same viewpoint, the HLB value is more preferably 9 or more, and further preferably 10 or more. Further, from the viewpoint of maintaining the dispersibility of the cement, the HLB value is more preferably 16 or less, and further preferably 15 or less. As the HLB value, a value calculated from the Griffin equation described in detail in the following examples is used.

(Additive kit)
The additive kit of this embodiment has the shrinkage reducing agent and antifoaming agent individually packaged (packaged). The additive kit is a set of additives added to the hydraulic composition described below. The shrinkage reducing agent and antifoaming agent in the additive kit may be added to the hydraulic composition as a mixture thereof, or may be separately added to the hydraulic composition. When the shrinkage reducing agent and the antifoaming agent are added to the hydraulic composition as a mixture, the shrinkage reducing agent and the antifoaming agent are preferably mixed immediately before the addition. Since the additive kit has the shrinkage reducing agent and the antifoaming agent, the additive kit is useful for producing a hydraulic composition having a shrinkage reducing effect and a defoaming effect according to demand in a well-balanced manner. An additive kit is sometimes referred to as an additive package.

  Examples of the antifoaming agent include an alkylene oxide adduct different from the alkylene oxide adduct represented by the general formula (1); an oil-based antifoaming agent such as castor oil; a fatty acid-based antifoaming agent such as stearic acid; Examples thereof include silicone-based antifoaming agents; silica; and mineral oils. An antifoamer may be used individually by 1 type, and may be used in combination of 2 or more type. When the alkylene oxide adduct represented by the general formula (1) is used as the first alkylene oxide adduct, the defoamer is an alkylene oxide adduct different from the first alkylene oxide adduct, ie, the second The alkylene oxide adduct is preferably used. When the antifoaming agent is the second alkylene oxide adduct, it tends to be excellent in compatibility with the first alkylene oxide adduct.

Furthermore, from the viewpoint of obtaining high defoaming properties, the second alkylene oxide adduct is more preferably an alkylene oxide adduct represented by the following general formula (2).
R'O-[(PO) _x / (EO) _y ] -H (2)
In said general formula (2), R 'shows a hydrogen atom or a C1-C18 alkyl group or alkenyl group. The alkyl group or alkenyl group in R ′ is linear or branched. When the carbon number of R ′ is 18 or less, excellent handling properties tend to be obtained. The carbon number of R ′ may be 16 or less, or 14 or less.

[(PO) _x / (EO) _y ] in the general formula (2) is a polyoxyalkylene group in which x oxypropylene groups and y oxyethylene groups are bonded. One end of the polyoxyalkylene group is bonded to the R ′ (alkyl group or alkenyl group) via an ether bond, and the other end is bonded to a hydrogen atom.

  In the above general formula (2), x is the average number of moles of oxypropylene groups added in 1 mole of the second alkylene oxide adduct, and is preferably 11-100. When x is 11 or more, a sufficient defoaming effect can be obtained, and when x is 100 or less, the hydrophobicity of the second alkylene oxide adduct does not become too strong and the solubility in water decreases. There is a tendency that can be suppressed. From the same viewpoint, x is more preferably 20 to 100, further preferably 30 to 95, still more preferably 40 to 90, still more preferably 45 to 85, and 50 It is especially preferable that it is -80.

  In said general formula (2), y is the average addition mole number of the oxyethylene group in 1 mol of 2nd alkylene oxide adducts, and it is preferable that it is 0-20. When y is 20 or less, the hydrophilicity of the second alkylene oxide adduct does not become too strong, and a decrease in the defoaming effect can be suppressed. From the same viewpoint, y is preferably 19 or less, more preferably 18 or less, still more preferably 17 or less, still more preferably 16 or less, and 15 or less. Is particularly preferred. Moreover, from the viewpoint of imparting appropriate hydrophilicity, y is more preferably 1 or more, more preferably 2 or more, still more preferably 3 or more, and even more preferably 4 or more. 5 or more is particularly preferable.

  The second alkylene oxide adduct may be any of random addition type, block addition type, and random / block addition type.

  The weight average molecular weight of the second alkylene oxide adduct is not particularly limited, but is preferably 800 to 7000, more preferably 900 to 6500, still more preferably 1000 to 6000, still more preferably 2000 to 5500, and particularly preferably 3000. ~ 5000. When the weight average molecular weight is 800 or more, a higher defoaming effect tends to be obtained. When the weight average molecular weight is 7000 or less, higher handling properties tend to be obtained.

  The cloud point (hereinafter sometimes referred to as 1% cloud point) in a 1% by mass aqueous solution of the second alkylene oxide adduct is less than 18 ° C. When the cloud point in the 1% by mass aqueous solution of the second alkylene oxide adduct is less than 18 ° C., high defoaming property tends to be obtained. From the same viewpoint, the 1% cloud point of the second alkylene oxide adduct is more preferably less than 15 ° C, further preferably less than 10 ° C, and still more preferably less than 5 ° C. It is particularly preferred that the temperature is below 0 ° C.

  The additive kit of the present embodiment can have the shrinkage reducing agent and the antifoaming agent while considering that the amount of the shrinkage reducing agent and the antifoaming agent added to the hydraulic composition is within the range described below. The ratio of the 1st alkylene oxide adduct in an additive kit can be 15-99.8 mass% on the basis of the additive kit whole quantity. Moreover, the ratio of the antifoamer in an additive kit can be 0.2-85 mass% on the basis of the additive kit whole quantity.

  The additive kit of the present embodiment may have a pH adjuster, which will be described later, as necessary. The ratio of the pH adjusting agent is 0.01 to 5% by mass based on the total amount of the additive kit.

(Method for producing shrinkage reducing agent)
A method for producing the alkylene oxide adduct represented by the general formula (1) contained in the shrinkage reducing agent of the present embodiment will be described below.

Although there is no limitation in particular as a manufacturing method of the said alkylene oxide adduct, For example, following General formula (1a):
ROH (1a)
The production method including the step of supplying ethylene oxide and propylene oxide to the alcohol represented by However, R shows a C18 or more alkyl group or alkenyl group. The alkyl group or alkenyl group in R is linear or branched.

  In the production method described above, the addition reaction is performed so that the alkylene oxide is randomly added and / or block-added. Moreover, you may make addition reaction combining random addition and block addition.

  In the above production method, the addition reaction may be performed in only one step, or may be performed in a plurality of steps. As a manufacturing method which performs an addition reaction only by one process, the manufacturing method provided only with the process of adding a propylene oxide and ethylene oxide at random, etc. can be mentioned, for example. In addition, when the addition reaction is performed in a plurality of steps, for example, as a production method performed in two steps, for example, a step of adding a block of propylene oxide or ethylene oxide to an alcohol, and an alkylene oxide adduct after the block addition A production method comprising a step of randomly adding propylene oxide and ethylene oxide to a product; a step of randomly adding propylene oxide and ethylene oxide, and a step of block-adding propylene oxide or ethylene oxide to an alkylene oxide adduct after random addition The method etc. can be mentioned.

  The alcohol represented by the general formula (1a) is not particularly limited, but linear alkanols such as octadecanol, nonadecanol, and eicosanol; branched alkanols such as 1-methylheptadecanol; octadecenol And linear alkenols such as nonadecenol and eisenol; and branched alkenols such as 1-methylheptadecenol. These alcohols may be used alone or in combination of two or more.

  The addition reaction may be performed in the presence of a catalyst. The catalyst is not particularly limited. For example, hydroxides of alkali (earth) metals such as sodium hydroxide, potassium hydroxide, cesium hydroxide, calcium hydroxide, barium hydroxide, and strontium hydroxide; Alkali (earth) metal oxides such as potassium, sodium oxide, calcium oxide, barium oxide, magnesium oxide, and strontium oxide; alkali metals such as metal potassium and metal sodium; metals such as sodium hydride and potassium hydride Hydrides; alkali (earth) metal carbonates such as sodium carbonate, sodium bicarbonate, and potassium carbonate; and alkali (earth) metal sulfates such as sodium sulfate and magnesium sulfate. These catalysts may be used alone or in combination of two or more.

  Although there is no limitation in particular about the usage-amount of a catalyst, Preferably it is 0.001-10 mass parts with respect to 100 mass parts of alcohol, More preferably, it is 0.001-8 mass parts, More preferably, it is 0.01-6. Parts by mass, more preferably 0.05 to 5 parts by mass, particularly preferably 0.05 to 3 parts by mass. When the amount of the catalyst used is 0.001 part by mass or more, the addition reaction tends to proceed sufficiently. On the other hand, when the amount of the catalyst used is 10 parts by mass or less, there is a tendency to suppress coloring of the alkylene oxide adduct.

  In the above production method, it is preferable that raw materials such as alcohol and catalyst are charged into a reaction vessel, and degassing or dehydrating treatment is performed on the reaction vessel. Examples of the degassing method include a vacuum degassing method and a vacuum degassing method. Examples of the dehydration method include a heat dehydration method, a vacuum dehydration method, and a vacuum dehydration method.

  In the above production method, the addition reaction may be started from a reduced pressure state, may be started from an atmospheric pressure state, or may be started from a pressurized state. When starting from an atmospheric pressure state or a pressurized state, the addition reaction is preferably performed in an atmosphere of an inert gas. When the addition reaction is performed in an inert gas atmosphere, impurities generated due to side reactions between alkylene oxide and oxygen can be sufficiently removed, and also useful from the viewpoint of safety. This is preferable. The inert gas is not particularly limited, and examples thereof include nitrogen gas, argon gas, and carbon dioxide gas. These inert gases may be used alone or in combination of two or more.

  The initial pressure in the reaction vessel is not particularly limited. For example, the gauge pressure is preferably 0 to 0.50 MPa, more preferably 0 to 0.45 MPa, still more preferably 0 to 0.4 MPa, and still more preferably. 0 to 0.35 MPa, particularly preferably 0 to 0.3 MPa. When the initial pressure in the reaction vessel is 0 MPa or more, the amount of impurities generated tends to be reduced. On the other hand, when the initial pressure in the reaction vessel is 0.50 MPa or less, the reaction rate tends to be maintained high.

  When alkylene oxide is supplied to the alcohol, an addition reaction occurs. The pressure in the reaction vessel during the addition reaction is affected by the supply rate of alkylene oxide, the reaction temperature, the amount of catalyst, and the like. The pressure in the reaction vessel during the addition reaction is not particularly limited, but is preferably 0 to 5.0 MPa, more preferably 0 to 4.0 MPa, still more preferably 0 to 3.0 MPa, and still more preferably gauge pressure. 0 to 2.0 MPa, particularly preferably 0.1 to 1.0 MPa. When the pressure in the reaction vessel during the addition reaction is 0 MPa or more, the reaction rate tends to be maintained high. On the other hand, when the pressure in the reaction vessel during the addition reaction is 5.0 MPa or less, production tends to be easy.

  Although there is no limitation in particular as reaction temperature of addition reaction, Preferably it is 70-240 degreeC, More preferably, it is 80-220 degreeC, More preferably, it is 90-200 degreeC, Especially preferably, it is 100-190 degreeC, Most preferably, it is 110-180. ° C. When the reaction temperature is 70 ° C. or higher, the addition reaction tends to proceed sufficiently. On the other hand, when the reaction temperature is 240 ° C. or lower, coloring of the resulting alkylene oxide adduct and decomposition of the polyoxyalkylene group in the alkylene oxide adduct tend to be suppressed.

  The time required for the addition reaction (reaction time) is not particularly limited, but is preferably 0.1 to 100 hours, more preferably 0.1 to 80 hours, still more preferably 0.1 to 60 hours, and even more preferably. Is 0.1 to 40 hours, particularly preferably 0.5 to 30 hours. When the reaction time is 0.1 hour or longer, the addition reaction tends to proceed sufficiently. On the other hand, when the reaction time is 100 hours or less, a decrease in production efficiency tends to be suppressed.

  When the supply of the alkylene oxide is completed, the internal pressure in the reaction vessel gradually decreases as the alkylene oxide is consumed. The addition reaction is preferably continued until no change in internal pressure is observed. The addition reaction ends when no change in internal pressure is observed over a certain period of time. An unreacted alkylene oxide may be recovered by performing a heating and decompression operation or the like as necessary.

  Moreover, after completion | finish of addition reaction, you may neutralize and / or remove a catalyst as needed. The neutralization of the catalyst may be performed by a normal method. For example, when the catalyst is an alkaline catalyst, an acid such as hydrochloric acid, phosphoric acid, acetic acid, lactic acid, citric acid, succinic acid, acrylic acid, and methacrylic acid is used. The method of adding and performing is mentioned.

  The removal of the catalyst is not particularly limited, and for example, a method of solid-liquid separation after adsorbing the catalyst to the adsorbent can be mentioned.

(Hydraulic composition)
The shrinkage reducing agent and additive kit of the present embodiment are suitably used for hydraulic compositions. The hydraulic composition includes a hydraulic component and the shrinkage reducing agent. The content of the alkylene oxide adduct represented by the general formula (1) in the hydraulic composition is preferably 0.001 to 10 parts by mass with respect to 100 parts by mass of the hydraulic component, 0.005 More preferably, it is -5 mass parts, and it is still more preferable that it is 0.01-2 mass parts. When the content of the alkylene oxide adduct is equal to or higher than the lower limit value, the shrinkage reduction effect tends to be sufficiently obtained. When the content of the alkylene oxide adduct is equal to or lower than the upper limit value, the shrinkage reducing agent remaining in the cured body is a fragile phase. Thus, there is a tendency that it is possible to suppress a decrease in compressive strength.

  Moreover, when a hydraulic composition contains an antifoamer, content of the said antifoamer in a hydraulic composition is 0.0001-0.30 mass parts with respect to 100 mass parts of hydraulic components. It is preferably 0.0010 to 0.25 parts by mass, and more preferably 0.0020 to 0.22 parts by mass. When the content of the antifoaming agent is not less than the above lower limit value, the antifoaming effect tends to be sufficiently obtained, and when it is not more than the above upper limit value, good freeze-thaw resistance tends to be maintained.

  The hydraulic component includes cement, and can include gypsum in addition to cement as long as the effects of the present invention are not significantly impaired.

  Examples of the cement include Portland cement (JIS R5210); Eco-cement (JIS R5214); Blast furnace cement (JIS R5211), Silica cement (JIS R5212) and fly ash cement (JIS R5213) and other mixed cements; Special cements such as alumina cement Etc. A cement may be used individually by 1 type and may be used in combination of 2 or more type.

  Several types of alumina cements having different mineral compositions are known and are commercially available, but the main component is a calcium aluminate composition, and commercially available products can be used regardless of the type.

  As the gypsum, gypsum such as anhydrous or semi-water can be used regardless of the kind thereof, and one kind may be used alone, or two or more kinds may be used in combination.

  The content of the hydraulic component in the hydraulic composition is preferably 20.0 to 60.0% by mass, more preferably 30.0 to 50.0% by mass, and 35.0 to 45. More preferably, it is 0.0 mass%, and it is especially preferable that it is 40.0-45.0 mass%. When the content of the hydraulic component is 60.0% by mass or less, there is a tendency to suppress cracking and the like in the curing process due to a decrease in flow characteristics and an increase in adiabatic temperature. Moreover, when the content of the hydraulic component is 20.0% by mass or more, there is a tendency to suppress a decrease in compressive strength and bleeding.

  The hydraulic composition may further contain a fine aggregate, an expansion material, a fluidizing agent, a thickener, a pH adjusting agent, a setting adjusting agent, a resin powder, an inorganic fine powder, and the like.

  Fine aggregates include silica sand, river sand, sea sand, mountain sand, crushed sand, etc., pulverized products such as urethane foam, EVA (ethylene / vinyl acetate copolymer resin) foam and foamed resin, and alumina cement clinker fine bone. Materials and the like. Among these, the fine aggregate is preferably sand such as quartz sand, river sand, sea sand, mountain sand, and crushed sand. In addition, when the said hydraulic composition does not contain coarse aggregate, there exists a tendency for the effect of the shrinkage reducing agent of this embodiment to be acquired more notably.

  From the viewpoint of suppressing material separation of the hydraulic composition, the fine aggregate is preferably composed only of particles having a particle diameter of less than 1180 μm, preferably particles having a particle diameter of less than 850 μm. That is, the mass ratio of particles having a particle diameter of 1180 μm or more with respect to the entire fine aggregate is preferably 0 mass%, and the mass ratio of particles having a particle diameter of 850 μm or more is more preferably 0 mass%. The particle diameter of the fine aggregate can be measured using several sieves having different opening dimensions as defined in JIS Z 8801-2006. Further, in this specification, “the mass ratio of particles having a particle diameter of 1180 μm or more” means the entire fine aggregate of fine aggregate particles remaining on the sieve without passing through the sieve when a sieve having an opening of 1180 μm is used. The mass ratio with respect to.

  Further, from the viewpoint of improving the workability of the hydraulic composition, the mass ratio of the fine aggregate particles having a particle diameter of less than 75 μm is preferably 10% by mass or less, more preferably 5% by mass or less. More preferably, it is at most mass%. In the present specification, the term “mass ratio of particles having a particle diameter of less than 75 μm” refers to the mass ratio of fine aggregate particles passing through the sieve to the whole fine aggregate when a sieve having an opening of 75 μm is used. .

  The content of the fine aggregate in the hydraulic composition is preferably 60 to 250 parts by mass, more preferably 80 to 200 parts by mass, and more preferably 100 to 180 parts per 100 parts by mass of the hydraulic component. It is more preferable that it is a mass part, and it is especially preferable that it is 120-160 mass parts. There exists a tendency for favorable hardened | cured material strength to be acquired because content of a fine aggregate exists in the said range.

  Examples of the expansion material include inorganic expansion materials and metal expansion materials. An inorganic expansion material tends to improve long-term crack resistance by producing a hydrate having expandability in the curing process and mainly suppressing long-term shrinkage after initial shrinkage.

  As the inorganic expansion material, calcium sulfoaluminate-based expansion material containing an ettringite-forming substance such as calcium sulfoaluminate as an expansion component, quick lime expansion material containing free quick lime as an expansion component, quick lime-gypsum expansion material, And calcined dolomite. An inorganic type expansion material may be used individually by 1 type, and may be used in combination of 2 or more type. The inorganic expansion material is preferably a quick lime-based expansion material or a quick lime-gypsum expansion material containing quick lime as an active ingredient which has a strength enhancement effect in a low-temperature environment by a hydration heat generation during reaction as well as a shrinkage compensation effect, A gypsum-based expansion material is more preferable. Although the quick lime content in these expansion | swelling materials is not specifically limited, Since a hydration reaction may advance rapidly in what has a quick lime content (including 100 mass%), the quick lime content in an expansion | swelling material is 80. It is preferable that it is below mass%.

  The content of the inorganic expansion material in the hydraulic composition is preferably 1.0 to 13.0 parts by mass, and 3.0 to 11.0 parts by mass with respect to 100 parts by mass of the hydraulic component. More preferably, it is more preferably 5.0 to 9.0 parts by mass. There exists a tendency which can express the effect which suppresses long-term shrinkage in a hardening process because content of an inorganic type expansion material is 1.0 mass part or more. When the content of the inorganic expansion material is 13.0 parts by mass or less, excessive expansion during the curing process and cracks due to expansion tend to be suppressed.

  Examples of the metal-based expansion material include metal powder such as aluminum powder and iron powder. From the aspect of specific gravity, the metal-based expansion material is preferably aluminum powder. The aluminum powder preferably conforms to the second type of JIS K-5906 “Aluminum powder for coating”.

  Examples of the fluidizing agent include polycarboxylic acid fluidizers and naphthalene sulfonic acid fluidizers. It is preferable to contain at least one of these fluidizing agents.

  Examples of the thickener include cellulose, protein, latex, modified acrylic and water-soluble polymer. The thickener is preferably a modified acrylic or cellulose thickener. Moreover, a thickener may be used individually by 1 type and may be used in combination of 2 or more type.

  The pH adjuster is not particularly limited, and examples thereof include inorganic acids such as hydrochloric acid, sulfuric acid, sulfurous acid, persulfuric acid, phosphoric acid, phosphorous acid, nitric acid, nitrous acid, and carbonic acid; formic acid, acetic acid, propionic acid, butyric acid, Isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, 2-ethylhexylic acid, lauric acid, stearic acid, oleic acid, elaidic acid, erucic acid, malonic acid, succinic acid, glutaric acid, adipic acid, lactic acid, tartaric acid Organic acids such as citric acid, malic acid, gluconic acid, acrylic acid, methacrylic acid and maleic acid; and salts of the above organic acids or inorganic acids. The salt of the organic acid or inorganic acid is sodium acid selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, propionic acid, butyric acid, succinic acid, glutaric acid, citric acid, malic acid and gluconic acid, Preference is given to potassium, magnesium and calcium salts. A pH adjuster may be used individually by 1 type, and may be used in combination of 2 or more type. It is preferable that content of the pH adjuster in a hydraulic composition is 0.0001-5 mass parts with respect to 100 mass parts of alkylene oxide adducts.

  The setting modifier can be added as appropriate within the range that does not impair the properties depending on the hydraulic component to be used, and the components, addition amount and mixing ratio of the setting accelerator and setting retarder are appropriately selected, and the pot life And condensation can be adjusted.

  Examples of the resin powder include resin powders prepared by spray-drying an emulsion polymerized polymer emulsion such as an ethylene / vinyl acetate copolymer and an acrylic polymer.

  Examples of the inorganic fine powder include calcium carbonate, blast furnace slag, fly ash, silica fume, and molten slag.

(Hydraulic mortar)
A hydraulic mortar can be obtained by kneading the hydraulic composition and water using a kneading apparatus or a mixer facility having a kneading mechanism.

  The above hydraulic mortar is used for tunnel and shield backfilling, dam joints, repair and reinforcement of structures, reinforcing joints, fixing of machine foundations, repair of sewers, etc., and construction of civil engineering and construction fields. In various constructions, it has a high fluidity, non-shrinkage, and high strength, so its utility value is great.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to these Examples.

<Evaluation method>
(1) 1% cloud point of alkylene oxide adduct A cloud point measuring instrument for measuring the 1% cloud point of an alkylene oxide adduct will be described with reference to FIG. In the cloud point measuring instrument 1, the lower end of the test tube 3 is inserted into the beaker 2 in which the ice water 9 is stored. The test tube 3 is held by a clamp, and the lower end of the test tube 3 is disposed in the ice water 9 in the beaker 2. In the test tube 3, a 1% by mass aqueous solution 8 of an alkylene oxide adduct obtained in the following Examples and Comparative Examples is introduced. Inside the test tube 3, a thermometer 5a for measuring the temperature of the 1% by mass aqueous solution 8 of the alkylene oxide adduct is fixed. Inside the beaker 2, a pipe heater 6 for heating the ice water 9 and a thermometer 5b for measuring the temperature of the ice water 9 are fixed.

The thermometer 5 a is held through the rubber plug 4. The beaker 2 is installed on a magnetic stirrer 7 a that can stir the ice water 9, and a stirrer chip 7 b is disposed in the beaker 2. Details of the tools are as follows.
Beaker 2: Capacity 1000mL, diameter 120mm, height 150mm
Test tube 3: diameter 20 mm, height 180 mm, distance 20 mm between the bottom of the test tube 3 and the bottom of the beaker 2, and the water level of the beaker 2 is 10 cm higher than the level of the 1 mass% aqueous solution of the alkylene oxide adduct in the test tube 3 Thus, the test tube 3 is installed.
Rubber stopper 4: Diameter 20mm
Thermometer 5a, 5b: -20 ° C to 100 ° C, 1/10 ° C scale Pipe heater 6: Length of about 120mm, made of copper

  A 1% by mass aqueous solution of an alkylene oxide adduct obtained in the following Examples and Comparative Examples was prepared, and 10 mL was collected in a test tube 3. The test tube 3 was placed in the ice water 9 as described above, and it was confirmed that the temperature of the 1% by mass aqueous solution 8 of the alkylene oxide adduct was 0 ° C. The pipe heater 6 and the magnetic stirrer 7a were connected to a power source, and the ice water 9 in the beaker 2 was heated while stirring with the magnetic stirrer 7a. The ice water 9 was heated so that the 1 mass% aqueous solution 8 of the alkylene oxide adduct was heated at a rate of 0 ° C. to 0.2 ° C./min, and the cloudiness of the aqueous solution was visually confirmed. The temperature when the aqueous solution began to cloud and clouding was observed up to the center of the mercury bulb of the thermometer 5a was taken as the cloud point. In addition, even when the temperature of the 1 mass% aqueous solution 8 of alkylene oxide adduct was 0 degreeC, when cloudiness was recognized, it was judged that a cloud point was less than 0 degreeC. In addition, even when the temperature of the 1% by mass aqueous solution 8 of the alkylene oxide adduct reached 99 ° C., when cloudiness was not observed, it was judged that the cloud point exceeded 99 ° C.

式（ｉ）中、親水基部分とは、例えば、上記式（１）又は（２）で表されるアルキレンオキサイド付加物を構成するＲＯ−、Ｒ’Ｏ−、（ＰＯ）、及び（ＥＯ）のうちの（ＥＯ）のみを示すものとした。上記式（１）で表されるアルキレンオキサイド付加物であって、例えばｑ＝５である場合には、アルキレンオキサイド付加物の分子量のうちの親水基部分相当量は２２０（＝４４×５）となる。 (2) HLB value of alkylene oxide adduct The HLB value of the alkylene oxide adduct obtained in the following Examples and Comparative Examples was calculated from the following formula (i) (Griffin formula).

In the formula (i), the hydrophilic group portion is, for example, RO—, R′O—, (PO), and (EO) constituting the alkylene oxide adduct represented by the above formula (1) or (2). Of these, only (EO) was shown. In the case of the alkylene oxide adduct represented by the above formula (1), for example, when q = 5, the equivalent amount of the hydrophilic group in the molecular weight of the alkylene oxide adduct is 220 (= 44 × 5). Become.

(3) Weight average molecular weight of alkylene oxide adduct The alkylene oxide adduct obtained in the following Examples and Comparative Examples was dissolved in tetrahydrofuran so that the nonvolatile content concentration was about 0.2% by mass. Prepared. Using the eluent, the weight average molecular weight of the alkylene oxide adduct was measured under the following conditions by gel permeation chromatography (GPC). Polyethylene glycol having a known molecular weight was used for preparing a calibration curve.
Device name: HLC-8220 (manufactured by Tosoh Corporation)
Column: One each of KF-G, KF-402HQ, and KF-403HQ connected in series (all manufactured by Shodex)
Eluent: Tetrahydrofuran Injection amount: 10 μL
Eluent flow rate: 0.3 mL / min Temperature: 40 ° C

(4) Average addition mole number of oxyalkylene group About 30 mg of alkylene oxide adducts obtained in the following Examples and Comparative Examples were weighed into a sample tube having a diameter of 5 mm, and about 0.5 mL of deuterated chloroform was added and dissolved. Then, a measurement solution was prepared. A ¹ H-NMR spectrum of the measurement solution was obtained using a ¹ H-NMR measuring apparatus (manufactured by BRUKER, trade name: AVANCE400, 100 MHz). ^{In the 1} H-NMR spectrum, the integrated values of the peaks attributed to the oxypropylene group and the oxyethylene group were read, and the average addition mole number of the oxypropylene group and the average addition mole number of the oxyethylene group were calculated. The number of carbon atoms of the terminal alkoxy group (RO- in the above formula (1) or R'O- in the above formula (2)) is the integrated value of the peak attributed to the alkyl group or alkenyl group. Read and calculated.

(5) Surface tension of alkylene oxide adducts 0.1% by weight aqueous solutions of alkylene oxide adducts obtained in the following examples and comparative examples were used as test solutions, and an automatic surface tension meter (trade name: Tensiometer K100, manufactured by KRUSS). ) Was measured under a measurement condition at a temperature of 25 ° C. by the Wilhelmy method.

(6) Air content Using hydraulic mortars obtained in the following examples and comparative examples, conforming to the mortar air content measurement method stipulated in JIS A5308: 1998 appendix 3 sand test method with compressive strength of mortar Then, the amount of air (volume%) was measured.

(7) Shrinkage (length change)
A length change measuring device 10 shown in FIG. 4 was used for measuring the length change of the hydraulic mortar. 4A is a top view of the length variation measuring device 10, and FIG. 4B is a cross-sectional view taken along the line bb in FIG. As shown to Fig.4 (a), the length variation measuring apparatus 10 has the mold 11 which forms the accommodating part 20 in which a hydraulic mortar is cast. Cushioning materials 14 are respectively installed on the inner side and the outer side of the side wall at one end in the longitudinal direction forming the accommodating portion 20 of the mold 11. The SUS rod 13a that can move in the xy direction is installed through the side wall of the mold 11 and the cushioning materials 14 and 14 provided between the side walls. SUS disks 12a and 12b are provided at both ends of the SUS rod 13a. Here, SUS refers to a stainless steel material specified in JIS.

  A SUS rod 13 b is installed on the inner surface of the other side wall surface of the mold 11. A SUS disk 12c is provided at the end opposite to the side wall surface of the SUS bar 13b so as to face the SUS disk 12b. The distance d between the SUS disk 12b and the SUS disk 12c before measurement is 210 mm. As shown in FIG. 4B, a fluororesin sheet 16 is installed on the inner surface of the mold 11. Here, the height h of the inner wall of the mold 11 is 30 mm, and the width w in the short direction of the bottom of the inner wall of the mold 11 is 40 mm.

  When the hydraulic mortar placed in the mold 11 is contracted, the SUS disks 12a and 12b are displaced from the position before measurement in the direction of the arrow x, and when the hydraulic mortar is expanded, the mortar is displaced in the direction of the arrow y. A laser displacement sensor 15 capable of measuring the displacement in the xy direction of the SUS disk 12a is disposed outside the mold 11.

  The hydraulic mortar immediately after kneading obtained in the following examples and comparative examples is placed in the accommodating part 20 of the mold 11 up to the height of the mold, and the length from immediately after casting in the curing conditions described later to 24 hours later. (Displacement a in the xy direction of the SUS disk 12a) was measured every minute. The curing of the hydraulic mortar kneaded under the following kneading condition A is in the atmosphere (curing condition A) at a temperature of 20 ° C. and a humidity of 65% RH, and the curing of the hydraulic mortar kneaded under the following kneading condition B is at a temperature of 35 ° C. The test was performed in the atmosphere of 65% RH (curing condition B).

The amount of change in the length of the hydraulic mortar is 1000 times by dividing the displacement a (μm) in the xy direction of the SUS disk 12a by the distance d between the SUS disk 12b and the SUS disk 12c before measurement. The calculated value (μm / m) was calculated (see the following formula (ii)). The length change amount (−) means contraction, and (+) means expansion.
Length change = (a × 1000) / d (ii)

Moreover, the length variation (μm / m) at the time when 12 hours passed immediately after placing was evaluated according to the following criteria.
A: The amount of change in length exceeds −500.
B: The length change amount is −500 or less and exceeds −700.
C: The length change amount is −700 or less and exceeds −1000.
D: The length change amount is −1000 or less and exceeds −1500.
E: The amount of change in length is −1500 or less.

(8) Flow value The flow value was measured in accordance with the simple table flow test method described in the guidelines for supervision of building repair works. That is, a vinyl chloride pipe (internal volume 200 mL) having an inner diameter of 50 mm and a height of 102 mm was placed on a 5 mm thick sheet glass, and after filling the hydraulic mortar obtained in the following Examples and Comparative Examples, Raised. After the spread stopped, the diameters in two directions at right angles were measured, and the average value was taken as the flow value (mm).

(9) Termination time For hydraulic mortar immediately after kneading obtained in the following examples and comparative examples, the termination time was determined in accordance with the mortar setting test method defined in the physical test method for cement of JIS R5201: 1997. (Min) was measured.

(10) Compressive strength The hydraulic mortars obtained in the following examples and comparative examples were cured in a mold in the air at a temperature of 20 ° C. and a humidity of 95% RH. On the next day, the cured body was demolded and then cured in water at 20 ° C. for 28 days to obtain a test body (φ5 × 10 cm). Based on JIS A-1108, the compressive strength (N / mm < ² >) was evaluated with respect to the test body.

(11) Freezing and thawing resistance The hydraulic mortars obtained in the following Examples and Comparative Examples were placed in a mold, demolded after 1 day, and then cured in water at 20 ° C. for 28 days to obtain 3 pieces. A specimen was obtained. The specimen was a rectangular parallelepiped having a square cross-section, the length of one side of the square was 100 mm, and the height was 400 mm.

  The freeze-thaw resistance of the cured body of hydraulic mortar is based on the test method described in JIS A 1148-2010 “Freeze-thaw test method for concrete (Method A)”, and the freeze-thaw process is repeated for the above specimen. Evaluation was made by measuring the primary resonance frequency and mass of the flexural vibration of the specimen after the freeze-thaw step, and calculating the relative kinematic modulus and mass reduction rate. One cycle of the freezing and thawing step consists of a freezing step for lowering the center temperature of the specimen from 5 ° C. to −18 ° C. and a thawing step for raising the temperature from −18 ° C. to 5 ° C. Went in time. The relative kinematic elastic modulus and mass reduction rate were calculated every 30 cycles.

<Preparation of shrinkage reducing agent>
( Reference Example 1-1 )
Steril alcohol (molecular weight 270) 100 g and potassium hydroxide 0.3 g were charged in a 1 L autoclave connected with ethylene oxide and propylene oxide supply lines, respectively, and the autoclave was purged with nitrogen and stirred. Vacuum dehydration was performed at 80 ° C.

Subsequently, after raising the temperature to 130 ° C., 49 g of ethylene oxide and 279 g of propylene oxide were simultaneously supplied in about 120 minutes while maintaining a reaction temperature of 145 ± 5 ° C. and a reaction pressure of 3.5 ± 0.5 kg / cm ² .

After the supply of ethylene oxide and propylene oxide was completed, the reaction temperature was maintained and the product was aged until the internal pressure decreased and became constant, and cooled to 80 ° C. As a post-treatment, 3 g of a synthetic adsorbent (KYOWARD 700, Kyowa Chemical Industry Co., Ltd.) was added to the resulting reaction mixture, and the mixture was stirred at 90 ° C. for 1 hour in a nitrogen stream, and then the catalyst was removed by filtration. Thus, an alkylene oxide adduct 1 was obtained. The obtained alkylene oxide adduct 1 was used as the shrinkage reducing agent of Reference Example 1-1 .

  The average addition mole number p of propylene oxide of the obtained alkylene oxide adduct 1 was 13, and the average addition mole number q of ethylene oxide was 3. The weight average molecular weight was 1149, the surface tension was 32.5 mN / m, and the cloud point was 20 ° C. The carbon number of R is the same as the carbon number of the alcohol (stearyl alcohol) used as a raw material.

(Example 1-2 and Comparative Examples 1-1 to 1-9)
Alkylene oxide adducts 2 to 11 were obtained in the same manner as in Reference Example 1-1 except that the supply amounts of raw material alcohol, ethylene oxide, and propylene oxide were changed. The obtained alkylene oxide adduct 2 was used as the shrinkage reducing agent of Example 1-2, and the alkylene oxide adducts 3 to 11 were used as the shrinkage reducing agents of Comparative Examples 1-1 to 1-9, respectively. The characteristics of the resulting alkylene oxide adducts 1 to 11 are shown in Table 1.

<Preparation of hydraulic composition and hydraulic mortar>
( Reference Example 2-1, Example 2-2, Reference Example 2-3, Example 2-4, and Comparative Examples 2-1 to 2-12)
The hydraulic composition and water were kneaded under the following kneading conditions A and B in the parts by mass shown in Tables 3 to 6 below, and hydraulic mortars kneaded under the respective conditions were prepared. The amount of air, the amount of shrinkage, the flow value, the termination time, and the compressive strength were evaluated on the obtained hydraulic mortar according to the above method. Table 7 shows the evaluation results.

(1) Kneading condition A
In a thermostatic chamber at a temperature of 20 ° C. and a humidity of 65% RH, water cured at the same temperature as the thermostatic chamber was placed in a 2 L plastic container. The hydraulic composition was added while stirring at 300 rpm using a stirrer, and kneaded at 700 rpm for 2 minutes to obtain hydraulic mortar. As the stirrer, a 0.15 kW stirrer (manufactured by Shinto Kagaku Co., product number: Three-One Motor BL600) equipped with turbine blades was used.

(2) Kneading condition B
A hydraulic mortar was obtained in the same manner as in the kneading condition A except that it was kneaded in a thermostatic chamber at a temperature of 35 ° C. and a humidity of 65% RH.

(3) Kneading condition C
A hydraulic mortar was obtained in the same manner as in the kneading condition A, except that the kneading was performed in an outdoor laboratory where the temperature was 30 to 35 ° C. and the humidity was 45 to 60% RH.

The details of the names of the materials described in Tables 3 to 6 are as follows. In addition, the measurement method of the following specific surface area uses the brane air permeation | transmission apparatus prescribed | regulated to JISR5201-1997. The following mass ratio of the particles at each particle size is a value measured using several sieves having different opening dimensions as defined in JIS Z 8801-2006. The following viscosities are obtained by using a 2% by weight aqueous solution of a thickener using a B-type viscometer (BROOKFIELD digital viscometer: RVDV-1 +). 4. The value measured at a rotational speed of 12 rpm and 20 ° C.
Cement: Early strong Portland cement, Blaine specific surface area 4500 cm ² / g.
Table 2 shows the fine aggregate A: a mixture of No. 5 silica sand and No. 6 silica sand, and the mass ratio (particle size composition) of particles at each particle size.
Fluidizing agent A: polycarboxylic acid based fluidizing agent.
Thickener A: Modified acrylic thickener, viscosity 4,283 mPa · s.
Antifoaming agent 1: alkylene oxide adduct represented by formula (2). X in the formula (2) was 70 to 80, y was 10 or less, and R ′ was an alkyl group having 16 to 18 carbon atoms. The weight average molecular weight was about 5000. The cloud point was 0 ° C. or lower.

  In Comparative Example 2-1, which did not contain an alkylene oxide adduct, the amount of shrinkage was large. In Comparative Examples 2-2 and 2-3 in which the number of carbon atoms of the alkyl group R is small even if an alkylene oxide adduct is contained, and in Comparative Examples 2-4 to 2-8 in which the cloud point is small, the shrinkage is particularly high. Reduction effect could not be confirmed. On the other hand, in Comparative Examples 2-9 to 2-12 using an alkylene oxide adduct having a high cloud point, although the shrinkage reduction effect near 20 ° C. was confirmed, the amount of air could not be suppressed and the strength was lowered. In addition, the handling property was lowered.

Moreover, the hydraulic mortar obtained by the kneading conditions C in Reference Example 2-1 and Comparative Example 2-1 is stored in an outdoor experimental field (curing conditions C) at a temperature of 30 to 35 ° C. and a humidity of 45 to 60% RH. did. The graph which compared the time-dependent change of the shrinkage | contraction amount when it preserve | saves on the curing conditions C is shown in FIG. From FIG. 1, it can be confirmed that the shrinkage at the initial stage of hydration in Comparative Example 2-1 is remarkable, and the amount of shrinkage is greatly reduced in Reference Example 2-1 , compared to Comparative Example 2-1. In addition, the cured product obtained by storing under the curing condition C of Reference Example 2-1 did not confirm cracking, whereas the cured product obtained by storing under the curing condition C of Comparative Example 2-1. A large crack was confirmed.

( Reference Examples 2-5 to 2-7 and Comparative Example 2-13)
The hydraulic composition and water were kneaded under the above-mentioned kneading conditions A and B in the parts by mass shown in Table 9 below, and hydraulic mortars kneaded under the respective conditions were prepared. The amount of shrinkage was evaluated according to the above-mentioned method to the obtained hydraulic mortar. Table 10 shows the evaluation results. Moreover, the freeze-thaw resistance was evaluated according to the said method with respect to the hydraulic mortar obtained by Reference Example 2-7 and Comparative Example 2-13. The evaluation results are shown in FIG.

Details of the names of the new materials listed in Table 9 are as follows. In addition, the following mass ratio of the particle | grains in each particle diameter is the value measured using several sieves from which the opening dimension prescribed | regulated to JISZ8801-2006 differs. The following viscosities are obtained by using a 2% by weight aqueous solution of a thickener using a B-type viscometer (BROOKFIELD digital viscometer: RVDV-1 +). 4. The value measured at a rotational speed of 12 rpm and 20 ° C.
Table 8 shows the fine aggregate B: No. 5 silica sand, No. 6 silica sand and No. 8 silica sand, and the mass ratio (particle size composition) of particles at each particle size.
Inorganic expansive material: quick lime-gypsum based expansive material (content of quick lime: 50% by mass).
Metal-based expansion material: aluminum powder (content of particles having a particle diameter of 44 μm or less: 60 mass% or more)
Fluidizer B: Modified polycarboxylic acid fluidizer.
Thickener B: Methyl cellulose thickener (viscosity: 5,150 mPa · s).

( Reference Examples 2-8 to 2-11 )
A hydraulic composition and water were kneaded under the above-mentioned kneading conditions in the parts by mass shown in Table 11 below to prepare a hydraulic mortar. The amount of air was evaluated with respect to the obtained hydraulic mortar according to the said method. The evaluation results are shown in Table 12.

( Reference Examples 2-12 to 2-15 )
The hydraulic composition and water were kneaded under the above kneading conditions in the parts by mass shown in Table 13 below to prepare hydraulic mortar. The amount of air was evaluated with respect to the obtained hydraulic mortar according to the said method. The evaluation results are shown in Table 14.

Details of the names of the new materials listed in Table 13 are as follows.
Antifoaming agent 2: alkylene oxide adduct represented by the formula (2). X in the formula (2) was 70 to 80, y was 10 or less, and R ′ was an alkyl group having 16 to 18 carbon atoms. The weight average molecular weight was about 5000. The cloud point was 0 ° C. or lower.

From the results of Table 10, Comparative Examples 2-13 which do not contain the above alkylene oxide adducts in the hydraulic mortars of Reference Examples 2-5 to 2-7 containing the alkylene oxide adducts represented by the general formula (1). It was confirmed that the amount of shrinkage was greatly reduced as compared with. Moreover, as described in the graph of FIG. 2, the cured product obtained from the hydraulic mortar of Reference Example 2-7 containing the alkylene oxide adduct represented by the general formula (1), and the above alkylene oxide adduct The calculated values of the relative dynamic elastic modulus and the mass reduction rate were almost the same after 300 cycles with the cured product obtained from the hydraulic mortar of Comparative Example 2-13 not including (that is, after 300 cycles). The relative dynamic elastic modulus of Reference Example 2-7 was 103% and the mass reduction rate was 0.17%, and the relative dynamic elastic modulus of Comparative Example 2-13 was 102% and the mass reduction rate was 0.12%. ). From this, the hardened | cured material obtained from the hydraulic mortar containing the alkylene oxide adduct represented by General formula (1) is a freeze-thaw resistance substantially equivalent to the hardening body of the hydraulic mortar which does not contain the said alkylene oxide adduct. It was confirmed to have From the results of Table 12 and Table 14, in the hydraulic mortars of Reference Examples 2-7 to 2-10 and Reference Examples 2-12 to 2-15 containing an antifoaming agent, Reference Example 2 containing no antifoaming agent Compared with 11 hydraulic mortar, the air content of the cured product was greatly reduced. From this, it was confirmed that a cured body with a further reduced amount of air was obtained.

  DESCRIPTION OF SYMBOLS 1 ... Cloud point measuring instrument, 2 ... Beaker, 3 ... Test tube, 4 ... Rubber stopper, 5a, 5b ... Thermometer, 10 ... Length change measuring device, 11 ... Formwork, 12a, 12b, 12c ... Product made from SUS Discs, 13a, 13b ... SUS rods, 14 ... cushioning material, 15 ... laser displacement sensor, 16 ... fluororesin sheet, 20 ... housing part.

Claims (3)

An alkylene oxide adduct represented by the following general formula (1):
A shrinkage reducing agent for cement, wherein a cloud point of a 1% by mass aqueous solution of the alkylene oxide adduct is 50 to 72 ° C.
RO-[(PO) p / (EO) q] -H (1)
(In the formula (1), R represents an alkyl group or alkenyl group having 18 or more carbon atoms, the alkyl group or alkenyl group in R is linear or branched, PO is an oxypropylene group, EO represents an oxyethylene group, p and q are meets the following formula (a) ~ (C), a lower limit of q / p is 2.0, the upper limit of q / p is 10.0. )
1 ≦ p ≦ 14 (A)
10 ≦ q ≦ 30 (B)
p + q ≦ 30 (C)   The shrinkage reducing agent for cement according to claim 1, wherein the alkylene oxide adduct has an HLB value of more than 8 and 20 or less.   An additive kit comprising the cement shrinkage reducing agent according to claim 1 or 2 and an antifoaming agent.

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