JPH05148473A - Sealant composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition free from volume shrinkage, having excellent sealability, appearance, durability and weather-resistance and useful for building structure, etc., by compounding a nonionic asphalt emulsion, a synthetic resin emulsion, cement and a W/O-type cationic polymer emulsion at specific ratios. CONSTITUTION:The objective composition is composed of (A) 100 pts.wt. of a nonionic asphalt emulsion (having a solid content of 50-65 wt.%), (B) 10-70 pts.wt. of a synthetic resin emulsion (having a solid content of 50-70wt.%), e.g. synthetic rubber latex, (C) 20-100 pts.wt. of a cement such as Portland cement and (D) 1-7 pts.wt. of a W/O-type cationic polymer emulsion such as polydimethylaminoethyl methacrylate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing material composition which has excellent durability and weather resistance, and which seals and blocks seams of building structures, articles and the like, and which has almost no volume shrinkage after work hardening.

[0002]

2. Description of the Related Art As a water-based sealing material, there is a synthetic resin emulsion-based sealing material mainly composed of a cationic latex or an acrylic emulsion mainly composed of SBR, and those currently on the market are precast concrete boards and lightweight foam concrete. Widely used for joint treatment of boards and various siding boards. These sealing materials have the advantages that they are inexpensive, that they can be applied to wet surfaces, that they have excellent workability, and that they are water-based, so there is no risk of ignition and they are favorable in the work environment. However, there are drawbacks such as large volume shrinkage, long curing time, and washout due to rainfall before curing.

The conventional water-based sealing material has many advantages as described above, but on the other hand, the volume shrinkage ratio upon solidification is 20 to 35.
There should be about%. Also, it cannot be applied to concrete or mortar that has not solidified yet, and conversely, it is also impossible to place concrete or mortar immediately after applying these sealing materials. Further, in the uncured state, it has a drawback that it is weak in water and washed away by rain, and there are many drawbacks such that it cannot be used even in a place that is constantly immersed in water. In particular, a large volume contraction adversely affects the shielding property and the appearance that are most required as a sealing material.

In order to solve such a volume shrinkage, conventionally, an emulsion or the like is highly solidified and a filler such as calcium carbonate is often used. As a result, the viscosity of the sealing material is significantly increased, which has a great adverse effect on workability, and there is a risk that the emulsion may be broken.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a sealing material composition which not only prevents volumetric shrinkage and viscosity increase but also controls flow time, curing time and curing in water. Is.

[0006]

As a result of intensive studies, the inventors of the present invention have solved the above-mentioned conventional problems by skillfully combining a nonionic asphalt emulsion, a synthetic resin emulsion, cement, and a water-absorbing material. ..

That is, 100 parts by weight of nonionic asphalt emulsion (solid content 50 to 65% by weight), synthetic resin emulsion (solid content 50 to 75% by weight) 1
A sealant composition comprising 0 to 70 parts by weight of cement, 20 to 100 parts by weight of cement, and 1 to 7 parts by weight of a water-in-oil cationic polymer emulsion.

A feature of the present invention is that an aqueous sealant composed of a synthetic emulsion and cement, in particular, contains a nonionic asphalt emulsion and a water-in-oil cationic polymer emulsion.

Asphalt emulsions include various asphalts such as straight asphalt, blown asphalt, catalyst asphalt, asphalt compound, natural asphalt and pitch, which are dispersed in water containing a surfactant. Depending on the type of the surfactant, nonion, There are asphalt emulsions in which the anionic and cation ionicities are different. The anionic asphalt emulsion is not preferable because it is solidified when mixed with the anionic and cationic water-in-oil water-absorbing polymer emulsion. Further, cationic ones are not preferable because they are hardened when mixed with cement.

Therefore, in the present invention, a nonionic asphalt emulsion is preferable, and a solid content of 50 to 65% by weight is preferable. When the amount is less than 50% by weight, the storage stability is poor and the shrinkage is large, which is not desirable. If it is 65% by weight or more, the viscosity is high and the workability is deteriorated. The action of asphalt emulsion is
After construction, the water gradually evaporates to form a waterproof film and becomes a base material into which additives are mixed.

Examples of the synthetic resin emulsion used in the present invention include synthetic rubber latex, ethylene / vinyl acetate copolymer latex, vinyl chloride / vinyl acetate copolymer latex, styrene / acrylic resin emulsion, acrylic rubber emulsion and the like. Be done. Among them, synthetic rubber latex and acrylic rubber emulsion are preferable because they are excellent in water resistance, durability and rubber elasticity.

Among the synthetic rubber latices, cationic latices are used, and those disclosed in Japanese Patent Application No. 1-1469070 can be used. That is, a carboxy-modified synthetic rubber latex is used as a seed latex, and a monomer that is sparingly soluble or insoluble in water and has a cationic group, or a mixture of these with an ethylenically unsaturated monomer copolymerizable therewith. The cationic latex is obtained by neutralizing the polymer obtained by addition polymerization with an acid or a salt, or by quaternary ammonium chloride with a quaternizing agent. The cationic latex facilitates miscibility of the cement with the asphalt emulsion and improves adhesion.

In the present invention, as the acrylic rubber emulsion, a polymer mainly containing an alkyl (meth) acrylate having a glass transition point of 10 ° C. to −50 ° C. and having an alkyl group having 2 to 10 carbon atoms is used. To use. When the acrylic rubber emulsion is used, rubber elasticity, durability,
It is possible to increase elongation, prevent cracking, add thixotropic properties, and control fluidity.

The solid content of this synthetic resin emulsion is 50.
˜75 wt% is preferred, and 55-70 wt% is especially preferred. If it is less than 50% by weight, shrinkage increases, and if it exceeds 75% by weight, storage stability becomes poor and production becomes difficult.
The mixing ratio of the latex to 100 parts by weight of the asphalt emulsion is preferably 10 to 70 parts by weight, more preferably 20 to 50 parts by weight. If it is less than 10 parts by weight, the effect of adding rubber elasticity cannot be exhibited, and if it exceeds 70 parts by weight, the curing rate becomes extremely long and it becomes easy to separate from the asphalt. In addition, there is a problem that thixotropy increases and work becomes difficult.

The cement used in the present invention includes ordinary Portland cement (including white cement), fast-strength Portland cement, super fast-strength Portland cement, Roman cement, blast furnace cement, silica cement, fly ash cement, super fast-hardening cement and the like. A single or a mixture of hard materials can be used.

The mixing ratio of cement is 20 to 100 parts, preferably 30 to 70 parts, relative to 100 parts by weight of the nonionic asphalt emulsion. If it is 20 parts or less, the strength of the film cannot be obtained, and the apparent drying property becomes extremely slow. 100
If it is more than 10 parts by weight, the viscosity of the compound is largely increased and the rubber elasticity of the cured product is lost.

As the water-in-oil cationic water-absorbing polymer emulsion used in the present invention, an aqueous solution containing a water-soluble cationic vinyl monomer and a crosslinkable monomer is mixed with an organic dispersion containing an emulsifier. Average polymer particle system 10 in which a hydrophilic surfactant is added after emulsification and radical polymerization
It is a water-in-oil cationic water-absorbing polymer emulsion having a size of μm or less. (For example, those described in JP-A-63-232888). 1 to 7 parts by weight, preferably 1.5 to 5 parts by weight, is used per 100 parts by weight of the nonionic asphalt emulsion. If it is less than 1 part by weight, dispersibility in water after kneading is poor, which is not preferable. If the amount exceeds 7 parts by weight, the water resistance after curing is deteriorated, which is not preferable. This water-in-oil cationic water-absorbing polymer emulsion absorbs water of asphalt and latex, promotes thickening of the system, contributes to shape retention until cement hardening, and is effective in preventing shrinkage. It also has the effect of preventing the separation of the mixture of asphalt, synthetic resin emulsion and cement in water.

The sealant composition of the present invention contains calcium carbonate, talc, bentonite, gypsum, silica powder, silica sand, and the like as necessary for improving workability by adjusting viscosity and fluidity and adjusting time. It is also possible to mix an inorganic filler.

In the sealing material of the invention described above, the cement in the composition reacts with about 25 to 30% by weight of water relative to its own weight and is incorporated as a solid content. Further, the cationic water-absorbing polymer emulsion absorbs and retains the remaining water and expands. In the meantime, the reaction hardening of cement progresses and solidifies to form a shell, which prevents subsequent shrinkage due to water evaporation. As a result, the sealing part has a smooth finish without eye loss after construction,
It is possible to obtain a filling material that can function as a sealing material in terms of appearance and performance.

The sealing material of the present invention can be used in commercially available automatic mixing equipment for sealing materials and can be loaded into a cartridge by an automatic weighing and filling machine. The sealing material loaded in the cartridge by these devices is The filling operation can be performed using an extrusion gun or a caulking gun.

[0021]

EXAMPLES The present invention will be described in detail with reference to Examples, Comparative Examples and Reference Examples, but the present invention is not limited thereto. In the following, the number of parts is based on weight unless otherwise specified. The details of the test method are also shown. Reference Example 1 [Production Example of Cationic Latex] 70.3 g of carboxy-modified SBR latex (PH
8.3, solid content 48%), NN'-methylenebisacrylamide 0.4 and water 159.7 g were added, diethylaminoethyl methacrylate 37.5 g was added using a dropping funnel while stirring well, and then N ₂ gas was added. And left for 1 hour. Thereafter, 80 g of a 1% potassium persulfate aqueous solution was added, and the mixture was heated to 50 ° C. for polymerization, and the polymerization was completed after about 2 hours. After completion of the polymerization, dimethyl sulfate 25.
Cation was added by adding 5 g to obtain a stable cationic latex having a cationic colloid equivalent value of 0.32 meq / g. Reference Example 2 [Production Example of Acrylic Rubber Emulsion] Acrylic Acid 2-
To a monomer mixture consisting of 90 parts of ethylhexyl, 7 parts of acrylonitrile and 3 parts of methacrylic acid, 0.2 part of sodium lauryl sulfate as an anionic surfactant, 0.8 part of ammonium persulfate as a catalyst and sodium bisulfite as a reducing agent 0 Mix 3 parts and 100 parts of water,
Polymerization was carried out by a usual method for time, and the pH was adjusted to 7.0 with aqueous ammonia. Reference Example 3 [Production Example of Water-in-Water Cationic Water-Absorbing Polymer Emulsion] 309.8 g of methyl quaternary dimethylaminoethyl methacrylate quaternary compound, 0.09 g of N, N'-methylenebisacrylamide and water-soluble azo catalyst (V-50)
820 g of an aqueous solution containing 0.08 g of H. L. B. 4.2
Nonionic activator (sorbitan monooleate) 15g
Paraffin oil containing (boiling point range 200-230 ° C) 24
The mixture was emulsified with a homogenizer in 0 g. The emulsion was transferred to a 4-necked flask and polymerized at a polymerization temperature of 60 ° C. while degassing with N ₂ gas, and the polymerization was completed after about 4 hours. Test method 1 [fluidity] JIS A5758 (sealing material for construction)
Filling the sealant at room temperature of 20 ° C. using the slump test channel defined in 6.2 Slump Test,
10 minutes after standing vertically, the distance (mm) from the lower end of the groove portion of the grooved container to the hanging end of the mixture was measured. Test method 2 [Adhesive strength of mortar board] According to the item of 6.8 durability adherend of JIS A5758 (sealing material for construction), the mortar board is coated with the sealing material in a thickness of 3 mm and the temperature is 28 ° C at 28 ° C.
After curing for one day, a tensile adhesive strength test according to JIS 6.13 was performed. (Unit: Kg / cm ² ) Test Method 3 [Volume Shrinkage Ratio] A cylindrical specimen having an inner diameter of 5 cm and a height of 10 cm was prepared using a sealing material, and after curing, it was heated at 20 ° C. for 2 hours.
After curing for 8 days, the difference in diameter and height from the start of curing was measured, and the volumetric shrinkage rate was calculated. Test method 4 [Curing in water] A glass petri dish having a diameter of 5 cm and a height of about 1.5 cm was immersed in a container filled with tap water and seawater,
The sealing material was poured into the petri dish from the air, and after 28 days, the appearance and the degree of curing were confirmed by touching with fingers, and the cured material was measured for the degree of curing with a penetrometer. ◯ = curable in water, x = spillage, or not curable in water. Test method 5 [Initial curing time] Sealing material: diameter 5 cm, height 4 c
After pouring it into a polyethylene cup of m to a depth of 3 cm, it was left in a room at 20 ° C., and when pressed with a fingertip, the time until the sealing material did not adhere to the fingertip was measured and set as the initial curing time. .. Example 1 As a nonionic asphalt emulsion, 100 parts of a nonionic asphalt A emulsion (manufactured by Nisshin Chemical Co., Ltd.) was added with 30 parts by weight of the acrylic rubber emulsion prepared in Reference Example 2 as a synthetic resin emulsion while stirring to obtain a high-strength Portland cement ( After gradually adding 50 parts of Onoda Cement: early strength cement), 2 parts of a water-in-oil cationic water-absorbing polymer emulsion prepared in Reference Example 3 was added,
A putty-like sealing material was obtained. Using this, measurements were made according to the above-mentioned test methods, and the test results are shown in Table 1. Example 2 A sealing material was obtained under the same conditions as in Example 1 except that 30 parts of the acrylic rubber emulsion in Example 1 was replaced with 30 parts of the cationic latex produced in Reference Example 1, and the test results thereof are shown in Table- It was described in 1. Example 3 The amount of the early-strength Portland cement used in Example 1 was set to 7
A sealing material was prepared under the same conditions as in Example 1 except that the content was changed to 0 part, and the test results thereof are shown in Table 1. Example 4 To 100 parts of the nonionic asphalt A emulsion (manufactured by Nisshin Chemical Co., Ltd.) used in Example 1, 20 parts of the acrylic rubber emulsion manufactured in Reference Example 2 was added, and the super-rapid hardening cement (manufactured by Onoda Cement: Jet Cement) was gradually added, and then 4 parts of a water-in-oil cationic water-absorbing polymer emulsion produced in Reference Example 3 was added to obtain a putty-like sealing material. This was tested and the results are shown in Table-1. Example 5 The putty-like sealing material was obtained by changing the ultra-rapid cement used in Example 4 to 100 parts, 50 parts of an acrylic rubber emulsion and 3 parts of a water-in-oil cationic water-absorbing polymer emulsion. This was tested and the results are shown in Table-1. Comparative Example-1 Acrylic rubber emulsion 100 produced in Reference Example 2
100 parts of early strength Portland cement was gradually added to and mixed with the thickening agent (High Metroze 65-SH-40
00: 0.2 part of Shin-Etsu Chemical Co., Ltd.) was added and mixed to obtain an aqueous sealing material. Using this, a test was conducted in the same manner as in Example 1, and the results are shown in Table 1. Comparative Example-2 To 100 parts of the cationic latex produced in Reference Example 1, 100 parts of early-strength Portland cement was gradually added and mixed, and a thickener (High Metroze 65-SH-400 was further added.
0: 0.2 part by Shin-Etsu Chemical Co., Ltd.) was added and mixed to obtain an aqueous sealing material. Using this, a test was conducted in the same manner as in Example 1, and the results are shown in Table 1. Comparative Example-3 Acrylic rubber emulsion 100 produced in Reference Example 2
150 parts of calcium carbonate (NS # 200: manufactured by Nitto Koka Kogyo Co., Ltd.) was added to the above parts with stirring and mixed with stirring, and a thickener (High Metroses 65-SH-4000: manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts were added and mixed to obtain an aqueous sealing material. Using this, a test is conducted in the same manner as in Example 1,
The results are shown in Table-1.

[0022]

[Table 1]

[0023]

[Table 2]

[0024]

EFFECT OF THE INVENTION The sealant composition of the present invention does not have volume shrinkage, has good shielding properties and appearance, has a gentle viscosity increasing curve, and can adjust flow time and curing time. Since it can be cured in water, it can also be used in locations that are constantly immersed in water.

Claims (1)

[Claims] 1. A nonionic asphalt emulsion (solid content 5
0 to 65% by weight) 100 parts by weight, synthetic resin emulsion (solids content 50 to 75% by weight) 10 to 70 parts by weight, cement 20 to 100 parts by weight and water-in-oil cationic polymer emulsion 1 to 1. A sealing material composition comprising 7 parts by weight.