JP6842054B2 - Aqueous emulsion and water stop method - Google Patents

Description

The present invention relates to an aqueous emulsion for forming a water-stopping material and a water-stopping method using the aqueous emulsion.

Conventionally, a building frame made of a cement composition such as concrete may crack due to drying shrinkage or deterioration over time, and water such as rainwater or groundwater may enter the building from the cracked portion. Then, in that case, water stopping work is performed to stop water leakage by injecting a chemical solution into the water stopping target portion such as the cracked portion to form a water blocking object.

As this water-stopping method, there is a one-component water-stopping method in which one chemical solution is injected into the water-stopping target portion. For example, there are a method of injecting urethane prepolymer as the chemical solution and a method of injecting an aqueous emulsion as the chemical solution.

On the other hand, Patent Documents 1 and 2 describe urethane prepolymers and aqueous emulsions as methods having both immediate curability exhibited by the former urethane prepolymer injection method and long-term durability exhibited by the latter aqueous emulsion injection method. Is disclosed as a two-component water-stopping method in which the mixture is mixed immediately before injection. Then, according to the construction method, the water required for the reaction of cross-linking the urethane prepolymer and foaming and curing (FIG. 3C) is supplied from the aqueous emulsion, and the urethane prepolymer is cross-linked and cured in a relatively short time. On the other hand, since water is consumed in the aqueous emulsion by this supply, the resin solids dispersed in the emulsion are easily fused with each other, and the emulsion is cured in a relatively short time. Therefore, according to the two-component water blocking method, an instantly curable water blocking material can be formed. In addition, the water-stopping material can exhibit higher long-term durability than the water-stopping material formed by the one-component urethane prepolymer injection method based on the chemical stability derived from the resin solid content of the aqueous emulsion. it can.

Japanese Unexamined Patent Publication No. 2014-181486 Patent No. 5300162

However, in both of the two-component water-stopping methods of Patent Documents 1 and 2, no chemical reaction (chemical change) occurs between the resin solid content of the aqueous emulsion and the urethane prepolymer. Therefore, the water-stopping product formed by curing is a product in which the cured product of the urethane foam resin and the cured product of the resin solid content of the aqueous emulsion are connected only by intermolecular force at the interface between them, and are chemically bonded. Not integrated. Therefore, there is a problem that higher durability cannot be expected for such a water blocking object, and as a result, it is not possible to cope with a case where a stable water stopping effect is required for a longer period of time.

Further, when the aqueous emulsion is emulsified using a water-soluble polymer such as polyvinyl alcohol as in the two-component water-stopping method of Patent Document 2, the water-soluble polymer covering the resin solid content of the aqueous emulsion. However, there is a problem that the aqueous emulsion is difficult to cure because it hinders the fusion of the resin solids. Further, when the aqueous emulsion and the urethane prepolymer are mixed, the water-soluble polymer consumes the isocyanate group of the urethane prepolymer, which hinders the reaction between the urethane prepolymer and water. As a result, the Biuret reaction and the like are suppressed, the urethane prepolymer becomes difficult to crosslink, and there may be a problem that the curing time of the urethane prepolymer or the like becomes long. As a result, it is difficult to quickly obtain the water stopping effect by the water stopping method of Patent Document 2.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is that a water-stopping material formed by mixing an aqueous emulsion and a urethane prepolymer and being cured has a rapid water-stopping effect. The purpose is to make it work and to obtain a stable water-stopping effect for a longer period of time.

The main invention for achieving the above object is
An aqueous emulsion characterized by having water, an acrylic resin solid content having a molecular structure having a hydroxyl group, and an anionic surfactant.
(However, the aqueous emulsion containing the cycloalkyl group-containing polymerizable monomer as the acrylic resin solids content thereof, the aqueous emulsion containing an epoxy resin as an acrylic resin solids contents, the acrylic resin solids contents An aqueous emulsion containing an organic solvent , an aqueous emulsion containing a polyvalent mercapto compound as the content of the aqueous emulsion, an aqueous emulsion containing a water repellent as the content of the aqueous emulsion, and a cross-linking agent as the content of the aqueous emulsion. Aqueous emulsion, as the content of the aqueous emulsion (B) General formula (I)
M2O ・ XSiO2 ・ aq (I)
(In the formula, M represents an alkali metal belonging to Group 1A of the periodic table, X represents a positive value of 2 to 4.5, and aq represents an aqueous solution.) Excludes aqueous emulsions containing water-soluble silicates. .. )
Other features of the present invention will be clarified by the description of the present specification and the accompanying drawings.

According to the present invention, a water blocking material formed by mixing an aqueous emulsion and a urethane prepolymer and being cured to form a water blocking effect promptly exerts a water stopping effect and obtains a stable water stopping effect for a longer period of time. Can be done.

1A to 1D are explanatory views of the water blocking method of the present embodiment. It is a partially broken side view of the injection head 25 of the injection device 20 used in the water stop method. 3A to 3C are explanatory views of problems and the like when the aqueous emulsion E1 of the first conventional example is used as the second chemical solution. 4A to 4C are explanatory views of problems and the like when the aqueous emulsion E2 of the second conventional example is used as the second chemical solution. 5A to 5C are explanatory views of the action and effect when the aqueous emulsion E3 of the present embodiment is used. Table 1 shows the specifications of the materials used for the chemical resistance test of the durability test. Table 2 shows the types of chemicals subjected to the chemical resistance test. It is a graph of the tensile strength which is the tensile test result. It is a graph of the elongation at break which is the tensile test result. Table 3 shows the temperature conditions and the like of the heat resistance test and the water resistance test. It is a graph of the tensile strength which is the tensile test result. It is a graph of the elongation at break which is the tensile test result. Table 4 shows the specifications and test results of the aqueous emulsions E3 and E4 used in the test for confirming that the curability deteriorates when the aqueous emulsion E3 of the present embodiment contains PVA.

The description of this specification and the accompanying drawings will clarify at least the following matters.
It is an aqueous emulsion characterized by having water, a resin solid content having a molecular structure having a hydroxyl group, and an anionic surfactant.

According to such an aqueous emulsion, when mixed with a urethane prepolymer, the isocyanate group of the urethane prepolymer and the hydroxyl group of the resin solid content of the aqueous emulsion are chemically directly bonded and integrated based on a chemical reaction, whereby. A cured product that is difficult to decompose is formed. Therefore, based on such a cured product, the waterproof material can exhibit high durability in a longer period of time.

Further, the above-mentioned aqueous emulsion is emulsified with an anionic surfactant. Therefore, it is possible to suppress the use of a water-soluble polymer such as polyvinyl alcohol for emulsification, which makes it easy to avoid problems that may occur when emulsified with the water-soluble polymer.
For example, it is possible to suppress a decrease in the isocyanate groups of the urethane prepolymer that should react with the hydroxyl groups of the resin solid due to the reaction of the isocyanate groups of the urethane prepolymer with the hydroxyl groups of the water-soluble polymer. As a result, the hardened product that is difficult to decompose can be formed reliably and in a relatively short time. In addition, it is possible to prevent the water-soluble polymer from inhibiting the fusion of the resin solids of the aqueous emulsion, and as a result, the resin solids can be cured in a relatively short time. Further, it is possible to prevent the water-soluble polymer from interfering with the reaction between the urethane prepolymer and water, whereby the urethane prepolymer is crosslinked in a relatively short time to form a cured product of the polyurethane resin. be able to. And, from the above, the water-stopping material can quickly exert the water-stopping effect.

Such an aqueous emulsion
The weight average molecular weight of the resin solid content is preferably greater than 1000 and less than 2000000.

According to such an aqueous emulsion, the weight average molecular weight of the resin solid content is larger than 1000, so that a more stable cured product can be formed as a water blocking material based on the resin solid content.

It is desirable that such an aqueous emulsion does not contain a water-soluble polymer.

According to such an aqueous emulsion, the isocyanate group of the urethane prepolymer to react with the hydroxyl group of the resin solid content is reduced due to the reaction of the isocyanate group of the urethane prepolymer with the hydroxyl group of the water-soluble polymer. Can be prevented. As a result, the hardened product that is difficult to decompose can be formed reliably and in a relatively short time.
In addition, it is possible to prevent the water-soluble polymer from inhibiting the fusion of the resin solids of the aqueous emulsion, and as a result, the resin solids can be cured in a relatively short time.
Furthermore, it is possible to prevent the water-soluble polymer from interfering with the reaction between the urethane prepolymer and water, whereby the urethane prepolymer is crosslinked in a relatively short time to form a cured product of the polyurethane resin. It can be formed.

In such an aqueous emulsion, it is desirable that the hydroxyl value of the resin solid content is in the range of 1 to 100.

According to such an aqueous emulsion, the above resin solid content has a relatively large number of hydroxyl groups. Therefore, the hydroxyl group of the resin solid can be rapidly chemically directly bonded to the isocyanate group of the urethane prepolymer and integrated, whereby a cured product that is difficult to decompose can be reliably formed. ..

The water-stopping portion is characterized in that the water-stopping target portion is stopped by injecting the aqueous emulsion according to any one of the above and a liquid urethane prepolymer into the water-stopping target portion of the water-stopping target member. It is a construction method.

According to such a water stopping method, the above-mentioned aqueous emulsion and urethane prepolymer are injected into the above-mentioned water-stopping target portion. Therefore, it is possible to exert the same action and effect as the above-mentioned action and effect, whereby the water stoppage target portion can be quickly stopped and the water stoppage effect can be maintained for a long period of time. it can.

In such a water stopping method, it is desirable that the aqueous emulsion and the liquid urethane prepolymer are blended in a weight ratio of 100: 21 to 100: 100.

According to such a water stopping method, the above-mentioned action and effect can be surely achieved.

=== This embodiment ===
1A to 1D are explanatory views of the water blocking method of the present embodiment. Further, FIG. 2 is a partially broken side view of the injection head 25 of the injection device 20 used in the water stoppage method.
In this water-stopping method, a chemical solution is injected into a cracked portion 1pw which is a water-stopping target portion in a concrete structure 1 as a water-stopping target member to fill the cracked portion 1pw. In this example, the cracked portion 1 pw is illustrated as the water stop target portion 1 pw, but the present invention is not limited to this. That is, any portion having a void that may cause water leakage can be a water stop target portion, and for example, the concrete joint portion may be a water stop target portion 1 pw.

As shown in FIG. 1A, in this water stopping method, first, the injection device 20 is carried in and arranged in the vicinity of the concrete structure 1. The injection device 20 is a two-component mixing type device. That is, two tanks 22u and 22e for storing different types of chemicals, pumps 23u and 23e provided for each of the tanks 22u and 22e, and each chemical solution from each pump 23u and 23e via the respective high-pressure hoses 24u and 24e. Has an injection head 25 as an injection device 25 to which the hose is pumped. A liquid urethane prepolymer is stored as a first chemical solution in one tank 22u, and an aqueous emulsion is stored as a second chemical solution in the other tank 22e. Then, these urethane prepolymers and the aqueous emulsion are separately pumped and supplied to the injection head 25 by the corresponding pumps 23u and 23e, and are mixed in the flow path SP25c (FIG. 2) in the head 25 to be the same. It is discharged in a mixed state from the discharge port 25h of the head 25.

Specifically, as shown in FIG. 2, the injection head 25 is provided via a bifurcated base 25a, a base side cylinder 25b integrally provided on the base 25a, and an appropriate pipe joint 25j on the base side cylinder 25b. It has a tip-side tubular portion 25c that is provided substantially coaxially and detachably. The base 25a is provided with two flow paths R25au and R25ae, and the corresponding high-pressure hoses 24u and 24e of the above two high-pressure hoses 24u and 24e are connected to the respective flow paths R25au and R25ae, respectively. ing. Further, these two flow paths R25au and R25ae merge at a predetermined position in the base portion 25a to form one flow path R25a1, and the one flow path R25a1 is connected to the in-cylinder flow path SP25b of the base side tubular portion 25b. It is connected. Further, the in-cylinder flow path SP25b is connected to the in-cylinder flow path SP25c of the tip side cylinder portion 25c built in the mixer 26. Therefore, the urethane prepolymer and the aqueous emulsion pumped from the tanks 22u and 22e merge in the base portion 25a in the injection head 25, and when passing through the base side cylinder portion 25b and the tip side cylinder portion 25c. , These urethane prepolymers and the aqueous emulsion are stirred and mixed by the above-mentioned mixer 26 having a substantially spiral shape. Then, in the mixed state, it is discharged from the discharge port 25h of the tip side tubular portion 25c.

On the other hand, as shown in FIG. 1A, the injection hole 1h is provided in the concrete structure 1 to be stopped so as to be connected to the cracked portion 1pw at the same time as or in parallel with the carrying-in / arranging work of the injection device 20. To pierce. A plurality of such injection holes 1h are formed, and are formed side by side at a formation pitch of 200 mm or the like in each of the horizontal direction and the vertical direction, for example.

Then, as shown in FIG. 1B, the tip side cylinder portion 25c of the injection head 25 is inserted into the injection hole 1h, the pumps 23u and 23e are started, and the urethane prepolymer is inserted from the discharge port 25h of the tip side cylinder portion 25c. The mixture of the aqueous emulsion and the aqueous emulsion is discharged, whereby the mixture is injected into the cracked portion 1pw. The injected mixture cures in a relatively short time. That is, the water required for foaming and curing the urethane prepolymer is supplied from the aqueous emulsion, while this supply consumes water from the aqueous emulsion and cures the aqueous emulsion. Therefore, basically, not only the urethane prepolymer is foam-cured in a relatively short time, but also the aqueous emulsion is cured in a relatively short time.

When the injection is completed, the pumps 23u and 23e are stopped, or the flow paths R25au and R25ae in the injection head 25 are closed by a valve (not shown) to stop the discharge from the discharge port 25h. Then, as shown in FIG. 1C, the tip side tubular portion 25c of the injection head 25 is pulled out from the injection hole 1h. Then, the process shifts to an uninjected injection hole 1h (not shown in FIGS. 1A to 1D) located next to the injection hole 1h in the horizontal or vertical direction, and the above-mentioned injection operation is performed on the injection hole 1h. repeat. Further, as shown in FIG. 1D, the injected injection hole 1h is filled with an appropriate filler Z1 such as mortar to finish the injection hole 1h without a hole.

Here, as an example of the liquid urethane prepolymer which is the first chemical solution, a delayed curing type urethane resin can be exemplified. The delayed curing type urethane resin has a curing time of 30 minutes or more at room temperature (20 ° C.) when the urethane resin is added at a concentration of 10% by weight based on the total weight of the urethane resin and tap water. It is a thing. However, it is not limited to this. That is, a urethane resin other than the delayed curing type may be used.

On the other hand, as the aqueous emulsion which is the second chemical solution, the following two emulsions have been conventionally used. That is, the aqueous emulsion E1 of the first conventional example is obtained by emulsifying an acrylic resin having a molecular structure having no hydroxyl group as the resin solid content J1 in water W with an anionic or nonionic surfactant K1. Further, in the aqueous emulsion E2 of the second conventional example, an acrylic resin and a petroleum resin having a molecular structure having no hydroxyl group as the resin solid content J2 are watered with polyvinyl alcohol (hereinafter, also referred to as PVA) as a surfactant. It is emulsified in W.

However, in each of the aqueous emulsions E1 and E2 of the first conventional example and the second conventional example, there is a problem that the cured and formed water-stopping substances SB1 and SB2 are difficult to obtain a stable water-stopping effect for a longer period of time, and the water-stopping effect. Has a problem that it is difficult to obtain it promptly. 3A to 3C and 4A to 4C are explanatory views of problems and the like.

First, as shown in the left figure of FIG. 3A, the aqueous emulsion E1 of the first conventional example contains water W as a dispersion medium and a resin solid content having a molecular structure such as an acrylic resin (FIG. 3B) having no hydroxyl group. It has J1 and an anionic or nonionic surfactant K1. Examples of the anionic surfactant include _{sulfonates such as R-SO 3} Na and carboxylic acid salts such as R-COONa, and examples of the nonionic surfactant include polyoxyethylene alkyl ether and the like. Can be exemplified.

Then, as shown in FIG. 3A, when the aqueous emulsion E1 and the urethane prepolymer UPP are mixed, the water W supplied from the aqueous emulsion E1 reacts with the urethane prepolymer UPP as described above (FIG. 3C). Then, the urethane prepolymer UPP is crosslinked and foam-cured, and as a result, a cured product KPU of a polyurethane resin is formed as a cured product of the crosslinked polymer as shown in the right figure of FIG. 3A. As for the aqueous emulsion E1, the water W is consumed by supplying the water W to the urethane prepolymer UPP, so that the resin solids J1 and J1 such as acrylic resin dispersed in the aqueous emulsion E1 are mutually exclusive. It is fused and cured, thereby forming a cured product KJ1 having a resin solid content J1 (see the right figure of FIG. 3A).

However, in this case, since the urethane prepolymer UPP and the resin solid content J1 have not chemically reacted, they are not chemically bonded and integrated, that is, the cured products KJ1 and KPU formed separately are simply mixed. It's just in a state of being. Therefore, as shown in the right figure of FIG. 3A, a large interface BS1 exists between the cured product KPU of the polyurethane resin and the cured product KJ1 of the resin solid content J1, and the interface BS1 generally has an intermolecular force. The interface BS1 has a low strength because it works only. Therefore, higher durability cannot be expected for the water blocking material SB1 having such a large interface BS1, and as a result, a stable water stopping effect for a longer period cannot be expected.

On the other hand, as shown in the left figure of FIG. 4A, the aqueous emulsion E2 of the second conventional example contains water W as a dispersion medium and an acrylic resin (for example, acrylic) as a resin solid content J2 having a molecular structure having no hydroxyl group. It has an acid butyl ester), a petroleum resin, and PVA (FIG. 4B) as a surfactant. Then, even when the aqueous emulsion E2 and the urethane prepolymer UPP are mixed, the urethane prepolymer UPP is foamed and cured by a reaction with water W or the like (FIG. 3C) as in the case of the first conventional example described above. As a result, the urethane prepolymer UPP is crosslinked to form a cured product KPU of the polyurethane resin alone, and even in the aqueous emulsion E2, the resin solids J2 and J2 are fused to each other and cured. As a result, a cured product KJ2 having a resin solid content J2 is formed by itself (see the right figure of FIG. 4A). Therefore, in this case as well, the cured products KPU and KJ2 formed separately are simply mixed, and therefore, as shown in the right figure of FIG. 4A, the cured product KPU of the polyurethane resin and the resin A large interface BS2 exists between the solid content J2 and the cured product KJ2, and as a result, higher durability cannot be expected for the waterproof material SB2.

Further, in the case of this second conventional example, as shown in the left figure of FIG. 4A, the aqueous emulsion E2 is emulsified based on the hydroxyl groups (hydroxyl groups, OH groups) of PVA covering the outer periphery of the resin solid content J2. However, since the hydroxyl group is present in the PVA, as shown in FIG. 4C, the hydroxyl group reacts with the isocyanate group of the urethane prepolymer UPP, and as a result, reacts with water W ( FIG. 3C) The urethane prepolymer UPP to be used is reduced. Therefore, in this case, the urethane prepolymer UPP is difficult to crosslink, and as a result, the molecular weight of the cured product KPU of the polyurethane resin that is cured and formed becomes small. As a result, it becomes difficult for the water blocking material SB2 composed of the cured products KJ2 and KPU to exert a stable water stopping effect. Further, as shown in the left figure of FIG. 4A, since the resin solid content J2 of the aqueous emulsion E2 is covered with PVA, the PVA hinders the fusion of the resin solid content J2 and J2, respectively. As a result, the aqueous emulsion E2 becomes difficult to cure and the curing time becomes long, which makes it difficult to quickly obtain the water blocking effect.

Therefore, in this embodiment, the aqueous emulsion E3 having the following composition is used. That is, as shown in the left figure of FIG. 5A, this aqueous emulsion E3 has a resin solid content J3 having a molecular structure (molecular formula) having water W as a dispersion medium and a hydroxyl group (hydroxyl group, OH group) at the molecular terminal. (FIG. 5B) and an anionic surfactant K3.

Then, according to the aqueous emulsion E3 having such a composition, when mixed with the urethane prepolymer UPP, the isocyanate group of the urethane prepolymer UPP and the resin solid content J3 of the aqueous emulsion E3 are based on the chemical reaction as shown in FIG. 5C. The hydroxyl groups are chemically directly bonded and integrated, thereby forming a cured product KJ3PU that is difficult to decompose. Therefore, based on the cured product KJ3PU, the waterproof material SB3 shown on the right side of FIG. 5A can exhibit high durability in a longer period of time. Further, since most of the urethane prepolymer UPP and the resin solid content J3 are consumed in the above reaction, the amount of the cured product KPU of the polyurethane resin individually formed by the reaction with water W (FIG. 3C) is shown in FIG. 5A. As shown in the right figure of FIG. 5A, the amount of the cured product KJ3 of the resin solid content J3 individually formed by the fusion of the resin solids J3 and J3 of the aqueous emulsion E3 is also reduced as shown in the right figure of FIG. 5A. As shown in the figure, it decreases. Therefore, the size of these interface BS3s is also reduced, which also effectively contributes to the improvement of the durability of the water blocking material SB3.

Further, as shown in the left figure of FIG. 5A, this aqueous emulsion E3 is emulsified with an anionic surfactant K3. Therefore, the use of a water-soluble polymer such as PVA for emulsification can be suppressed, and the water-soluble polymer is not used in this example. That is, the aqueous emulsion E3 does not contain a water-soluble polymer such as PVA.
Therefore, the isocyanate group of the urethane prepolymer UPP that should react with the hydroxyl group of the resin solid content J3 is reduced due to the reaction of the isocyanate group of the urethane prepolymer UPP with the hydroxyl group of the water-soluble polymer such as PVA. You can prevent problems. As a result, when mixed with the urethane prepolymer UPP, the hardened product KJ3PU, which is difficult to decompose, can be formed reliably and in a relatively short time. Further, it is possible to prevent the problem that the water-soluble polymer inhibits the fusion of the resin solids J3 and J3 of the aqueous emulsion E3, and as a result, the resin solids J3 are cured in a relatively short time. be able to. Furthermore, it is possible to prevent the problem that the water-soluble polymer interferes with the reaction between the urethane prepolymer UPP and water W, whereby the urethane prepolymer UPP is crosslinked in a relatively short time to form a polyurethane resin. A cured product KPU can be formed. As a result of the above, the water in the cracked portion 1 pw can be stopped quickly.

As the resin solid content J3 having a molecular structure having a hydroxyl group, an acrylic resin having a molecular structure having a hydroxyl group as shown in FIG. 5B can be exemplified, and this is used here. However, the resin solid content J3 having a molecular structure having a hydroxyl group is not limited to this. For example, acrylic acid ester type, styrene acrylic acid ester type, ethylene vinyl acetate type, polypropionic acid ester type, polypropylene type, polyethylene type, polyester type, styrene butadiene rubber (SBR) type, chloroprene rubber (CR) type, natural rubber. It may be a resin solid content composed of (NR) or the like.

Further, it is desirable that the weight average molecular weight of the resin solid content J3 is larger than 1000, and more preferably 100,000 or more. Then, in this way, more stable cured products KJ3PU and KJ3 can be formed based on the resin solid content J3. Further, from the viewpoint of facilitating the polymerization reaction, which is a cross-linking reaction, the weight average molecular weight of the resin solid content J3 is preferably 2000000 or less, and preferably 1500,000 or less.

Further, the hydroxyl value of the resin solid content J3 is in the range of 1 to 100, preferably in the range of 20 to 80. Within such a range, the resin solid content J3 has a relatively large number of hydroxyl groups. Therefore, the hydroxyl group of the resin solid content J3 can be rapidly chemically directly bonded to the isocyanate group of the urethane prepolymer UPP and integrated, whereby the cured product KJ3PU, which is difficult to decompose, can be reliably formed. ..

The blending ratio of the aqueous emulsion E3 and the urethane prepolymer UPP at the time of mixing is selected from the range of, for example, 100: 21 to 100: 100 by weight.

6 to 9 are explanatory views of a durability test of the waterproof material SB3 formed by mixing the aqueous emulsion E3 of the present embodiment and the urethane prepolymer UPP and curing the mixture. Here, as a comparative example, a durability test of a waterproof material SB1 formed by mixing the aqueous emulsion E1 of the first conventional example and the urethane prepolymer UPP and forming the mixture is also performed. Table 1 of FIG. 6 shows the specifications of the materials used for the test.

First, the aqueous emulsions E3 and E1 of the present embodiment and the first conventional example shown in Table 1 of FIG. 6 were prepared, and a urethane resin was prepared as a urethane prepolymer UPP. Then, each of the aqueous emulsions E3 and E1 of the present embodiment and the first conventional example is mixed with urethane resin at a mixing ratio (weight ratio) of 1.5: 1 to prepare a cured product having a thickness of 1 mm. did. Then, after curing each cured product for 14 days, a test piece is punched out from each cured product with a dumbbell-shaped No. 3 punch, and then each test piece is used as one of the chemicals shown in Table 2 of FIG. Soaked for 91 days. Then, the day before the tensile test, each test piece was taken out from the chemical and dried overnight in an air temperature environment at room temperature, and then the tensile test was performed on each test piece at a tensile speed of 500 mm / min. The chemicals in Table 2 were selected assuming the usage environment in which the waterproof material is exposed.

The tensile test results are shown in FIGS. 8 and 9. Note that FIG. 8 is a graph of tensile strength, and FIG. 9 is a graph of elongation at break. Further, in both the graphs of FIGS. 8 and 9, the upper bar graph is the tensile test result of the test piece of the aqueous emulsion E3 of the present embodiment, and the lower bar graph is the test of the aqueous emulsion E1 of the first conventional example. It is a tensile test result of a piece.

Looking at FIG. 8, the tensile strength of the test piece of the aqueous emulsion E3 of the present embodiment is higher than that of the test piece of the aqueous emulsion E1 of the first conventional example for any of the chemicals. ing. Further, looking at FIG. 9, the elongation rate (%) at break is also higher in the test piece of the aqueous emulsion E3 of the present embodiment than in the test piece of the aqueous emulsion E1 of the first conventional example. Therefore, it was confirmed that the waterproof material SB3 cured and formed by using the aqueous emulsion E3 of the present embodiment exhibits high durability even in the assumed usage environment.

Here, the durability test is performed not only from the above-mentioned viewpoint of chemical resistance but also from the viewpoint of heat resistance and water resistance. The details are as follows.

First, in the same manner as in the above-mentioned chemical resistance test, a cured product having a thickness of 1 mm was prepared by mixing each of the aqueous emulsions E3 and E1 of the present embodiment and the first conventional example in Table 1 of FIG. 6 with a urethane resin. .. Then, after curing each cured product for 14 days, a test piece was punched out from each cured product with a dumbbell-shaped No. 3 punch to prepare the cured product.

Then, each test piece was placed in the environment shown in Table 3 of FIG. 10, that is, in the air at 20 ° C., 60 ° C., -18 ° C., and in water at 20 ° C., -18 ° C. (in ice). It was allowed to stand for 91 days. Then, the day before the tensile test, each test piece was taken out from the above environment and dried overnight in an air temperature environment at room temperature, and then a tensile test was performed on each test piece at a tensile rate of 500 mm / min. The conditions in Table 3 were set assuming the usage environment in which the waterproof material is exposed.

The tensile test results are shown in FIGS. 11 and 12. 11 is a graph of tensile strength, and FIG. 12 is a graph of elongation at break (%). Further, in both the graphs of FIGS. 11 and 12, the upper bar graph is the tensile test result of the test piece of the aqueous emulsion E3 of the present embodiment, and the lower bar graph is the test of the aqueous emulsion E1 of the first conventional example. It is a tensile test result of a piece.

Looking at FIG. 11, under any condition, the tensile strength of the test piece of the emulsion E3 of the present embodiment is higher than the tensile strength of the test piece of the aqueous emulsion E1 of the first conventional example. Further, looking at FIG. 12, the elongation rate (%) at break is also higher in the test piece of the aqueous emulsion E3 of the present embodiment than in the test piece of the aqueous emulsion E1 of the first conventional example. Therefore, it was confirmed that the water-stopping material SB3 cured and formed by using the aqueous emulsion E3 of the present embodiment exhibits high durability from the viewpoint of heat resistance and water resistance.

By the way, it has been described above that when the aqueous emulsion E3 of the present embodiment contains a water-soluble polymer such as PVA, the curability is lowered, but the inventors of the present application have confirmed this point by a test as well. ing. This will be described below.

Table 4 of FIG. 13 shows the specifications of the materials used in this test.
First, as shown in Table 4, as materials, an aqueous emulsion E3 of the present embodiment, an aqueous emulsion E4 obtained by further mixing PVA with the aqueous emulsion E3 of the present embodiment, and a urethane resin (Table 1) were prepared. Then, each of the aqueous emulsions E3 and E4 and the urethane resin were mixed at a mixing ratio (weight ratio) of 3: 1 to produce two kinds of mixtures. Then, the time until each mixture was cured and the resistance due to gelation was felt was measured as the curing time. The resistance was measured by palpation and visual inspection.

Table 4 also shows the curing time, which is the test result. In the case of the aqueous emulsion E4 mixed with PVA, the curing time is more than twice as long as in the case of the aqueous emulsion E3 not mixed with PVA. There is. Therefore, it was confirmed that when PVA was mixed with the aqueous emulsion E3 of the present embodiment, the curability was lowered.

=== Other embodiments ===
Although the embodiments of the present invention have been described above, the above-described embodiments are for facilitating the understanding of the present invention, and are not for limiting the interpretation of the present invention. Further, the present invention can be changed or improved without departing from the spirit thereof, and it goes without saying that the present invention includes an equivalent thereof. For example, the following modifications are possible.

In the above-described embodiment, the concrete structure 1 has been illustrated as an example of the water-stopping target member, but the present invention is not limited to this. For example, other cement compositions such as mortar structures may be used, or other cement compositions may be used.

1 Concrete structure (water stop target member),
1h injection hole, 1pw cracked part (water stop target part),
20 injection device,
22e tank, 22u tank,
23e pump, 23u pump,
24e hose, 24u hose,
25 Injection head (injection device),
25a base, 25b base side cylinder, 25c tip side cylinder,
25h discharge port, 25j pipe fitting,
26 mixer,
R25a1 flow path, R25ae flow path, R25au flow path,
SP25b in-cylinder flow path, SP25c flow path,
UPP Urethane Prepolymer,
E1 Aqueous Emulsion, E2 Aqueous Emulsion, E3 Aqueous Emulsion,
E4 aqueous emulsion,
W water,
K1 Surfactant, K3 Surfactant,
J1 resin solid content, J2 resin solid content, J3 resin solid content,
KJ1 hardened resin solid, KJ2 hardened resin solid,
KJ3 hardened resin solid,
KPU polyurethane resin cured product, KJ3PU cured product,
SB1 water stop, SB2 water stop, SB3 water stop,
BS1 interface, BS2 interface, BS3 interface,
Z1 filler,

Claims (6)

An aqueous emulsion characterized by having water, an acrylic resin solid content having a molecular structure having a hydroxyl group, and an anionic surfactant.
(However, the aqueous emulsion containing the cycloalkyl group-containing polymerizable monomer as the acrylic resin solids content thereof, the aqueous emulsion containing an epoxy resin as an acrylic resin solids contents, the acrylic resin solids contents An aqueous emulsion containing an organic solvent , an aqueous emulsion containing a polyvalent mercapto compound as the content of the aqueous emulsion, an aqueous emulsion containing a water repellent as the content of the aqueous emulsion, and a cross-linking agent as the content of the aqueous emulsion. Aqueous emulsion, as the content of the aqueous emulsion (B) General formula (I)
M2O ・ XSiO2 ・ aq (I)
(In the formula, M represents an alkali metal belonging to Group 1A of the periodic table, X represents a positive value of 2 to 4.5, and aq represents an aqueous solution.) Excludes aqueous emulsions containing water-soluble silicates. .. ) The aqueous emulsion according to claim 1.
An aqueous emulsion characterized by having a weight average molecular weight of the resin solid content of more than 1000 and not more than 2000000. The aqueous emulsion according to claim 1 or 2.
An aqueous emulsion characterized by not containing a water-soluble polymer. The aqueous emulsion according to any one of claims 1 to 3.
An aqueous emulsion characterized in that the hydroxyl value of the resin solid content is contained in the range of 1 to 100. The aqueous emulsion according to any one of claims 1 to 4 and a liquid urethane prepolymer are injected into the water-stopping target portion of the water-stopping target member to stop the water-stopping target portion. Water-stopping method. The water-stopping method according to claim 5, wherein the urethane prepolymer has a curing time of room temperature (20) when the urethane resin is added at a concentration of 10% by weight based on the total weight of the urethane resin and tap water. A water-stopping method characterized by being a delayed curing type that lasts for 30 minutes or more at (° C.).

Images