JP2942870B2 - Rubber asphalt waterproofing composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rubber asphalt-based waterproofing composition.
More specifically, the present invention relates to a rubber asphalt waterproofing composition which is used in a waterproofing method for civil engineering construction, in particular, an asphalt waterproofing normal temperature method and can be cured in a relatively short time and form a thick film having a large elongation.

[Conventional technology]

Conventionally, asphalt waterproofing thermal methods, sheet waterproofing methods, paint film waterproofing methods, etc. have been implemented as civil engineering waterproofing methods, but most of them are asphalt waterproofing thermal methods in terms of reliability, waterproofness, durability, etc. Is currently adopted. However, in this thermal method, asphalt must be heated and melted at the construction site, which may cause burns and may cause a fire at construction sites with various combustible materials. There is a problem with. Further, when asphalt is heated and melted, odors and smoke are generated, causing environmental pollution and easily causing pollution in urban areas.

Instead, an asphalt waterproof normal temperature method using a rubber asphalt emulsion has recently been adopted. In this method, a hydraulic inorganic substance such as cement is used to harden a rubber asphalt emulsion. This is to cure the rubber asphalt emulsion by using the water present in the rubber asphalt emulsion as water for hydration reaction of the hydraulic inorganic substance.

A method has been proposed in which Portland cement is used alone as a hydraulic inorganic substance for curing a rubber asphalt emulsion (JP-A-57-16070).

[Problems to be solved by the invention]

In the method using Portland cement alone as a hydraulic inorganic substance described in JP-A-57-16070, a cured coating film having sufficient water resistance can be obtained in a short time because the curing speed of the obtained composition is low. In addition, the curing speed of the coating film varies greatly with temperature, and in the case of thick coating, the difference in curing speed between the surface and the inside of the coating film increases, causing cracks in the formed coating film. There is a problem that it is easy.

Further, there is a problem that the formed cured coating film has a small elongation at the time of pulling, and the coating film is broken due to insufficient followability when a crack occurs on the base.

[Means for solving the problem]

The present inventors have conducted intensive studies to improve the above-mentioned problems, and as a result, as a hardening agent for rubber asphalt emulsion, 65
When Portland cement having a Blaine value of not less than 00 cm ² / g and a content of particles having a diameter of more than 5 μm of less than 40% by weight is used in a specific ratio, a composition obtained surprisingly is obtained. Has a sufficient pot life, cures in a relatively short time even in a wide temperature range from low to high, and has good crack elongation of the formed cured film, The present inventors have found that a stable thick film in which cracks are hardly generated can be formed, and based on this finding, the present invention has been completed.

That is, the present invention relates to a composition comprising a rubber asphalt emulsion and cement as a hardener, wherein the hardener has a Blaine value of 6500 cm ² / g or more, and a diameter of 5 μm.
a portland cement having a particle content of less than 40% by weight and a rubber asphalt-based waterproofing composition in which the curing agent is mixed in a range of 10 to 200 parts by weight per 100 parts by weight of a rubber asphalt emulsion. Gist of the present invention.

 Hereinafter, the present invention will be described in detail.

The rubber asphalt emulsion used in the rubber asphalt-based waterproofing composition of the present invention (hereinafter, referred to as the composition of the present invention) is not limited to the type of surfactant used, and may be any of a cationic, a nonionic or an amphoteric type. However, it is preferable to add and mix a curing agent and to maintain stability when performing the coating operation.

Examples of rubber used in the rubber asphalt emulsion include styrene-butadiene rubber, carboxy-modified styrene-butadiene rubber, acrylonitrile-butadiene rubber, methyl methacrylate-butadiene rubber, polybutadiene rubber, butyl rubber, isoprene rubber, chloroprene rubber, and natural rubber. And styrene-butadiene rubber or carboxy-modified styrene-butadiene rubber is particularly preferable.

Examples of asphalt used in the rubber asphalt emulsion include straight asphalt, blown asphalt, semi-blown asphalt, propane deasphalted asphalt, and natural asphalt (for example, lake asphalt).

The rubber and the asphalt are each independently,
Alternatively, two or more kinds can be used in combination.

The rubber asphalt emulsion may be produced by a usual method. Generally, first, a surfactant and a stabilizer are added to warm water, and the mixture is stirred until completely dissolved to prepare an emulsion.
The emulsified liquid and the asphalt melted by heating are mixed and emulsified using a colloid mill, a homogenizer or the like.

Examples of the surfactant include aliphatic amines, aliphatic diamines, aliphatic triamines, aliphatic amidoamines, aliphatic imidazolines or derivatives thereof, quaternary ammonium salts, amines having a heterocyclic nitrogen base, and other cationic compounds. Or an amphoteric surfactant, such as polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, oxyethylene-oxypropylene block copolymer, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid, glycerin fatty acid ester, polyoxyethylene Ethylene fatty acid esters, polyoxyethylene alkylamines, alkylalkanolamides, and other nonionic surfactants can be used.

As a stabilizer, sodium alginate, starch, gelatin, carboxymethylcellulose, methylcellulose,
What forms a hydrophilic sol in water, such as polyvinyl alcohol, is used.

The solid content of rubber asphalt emulsion is 50-85% by weight
Is preferable. If it is less than 50% by weight, the required amount of the curing agent increases, and the obtained cured product has low elongation and is brittle.
On the other hand, if it exceeds 85% by weight, it becomes difficult to add a curing agent.

Although the amount ratio of rubber to asphalt in the rubber asphalt emulsion is not particularly limited, it is preferable that the weight ratio of rubber / asphalt is in the range of 20/80 to 50/50 from the viewpoint of performance.

Examples of the Portland cement used in the composition of the present invention include ordinary Portland cement, early-strength Portland cement, ultra-high-strength Portland cement, moderate heat Portland cement, sulfate-resistant Portland cement, high iron oxide type Portland cement, and white Portland cement. These Portland cements can be used alone or in combination of two or more.

Portland cement used as a hardening agent for a rubber asphalt emulsion in the composition of the present invention requires a Blaine value of 6500 cm ² / g or more, preferably 7
000cm ² / g or more.

When Portland cement having a Blaine value of less than 6500 cm ² / g is used, a cured film having a sufficiently low water-resistant curing speed cannot be obtained in a short time because the curing speed of the obtained composition is low, and In the case of application, the problem that the difference in curing speed between the surface and the inside of the coating film is large and cracks easily occur in the formed coating film is not improved. Thus, in the composition of the present invention, the Blaine value is 6500 cm ² /
Portland cement of g or more is used.

However, even when a composition obtained using Portland cement having a Blaine value of 6500 cm ² / g or more, the formed cured coating film has a small elongation at the time of tension and follows the occurrence of cracks on the substrate. Insufficient properties may cause the coating to break.

In order to increase the elongation at the time of pulling of the formed cured coating film, improve the followability when a crack occurs on the substrate, and prevent the coating film from breaking, the Portland cement used is 6500 cm ² / g or more. It is necessary that the content of particles having a Blaine value and a diameter exceeding 5 μm is less than 40% by weight, preferably less than 30% by weight.

Portland cement having such a requirement can be obtained, for example, by subjecting the various commercially available Portland cements to a pulverization treatment under appropriate conditions and, if necessary, a classification treatment to adjust the particle size.

The amount ratio of the curing agent used in the composition of the present invention,
The range is 10 to 200 parts by weight, preferably 15 to 160 parts by weight, more preferably 20 to 140 parts by weight per 100 parts by weight of the rubber asphalt emulsion. If the amount is less than 10 parts by weight, it takes a long time to cure the rubber asphalt emulsion, and the desired degree of curing cannot be obtained. As the amount ratio of the curing agent is increased, the viscosity of the obtained composition tends to increase more rapidly and the pot life tends to be shorter. If the amount exceeds 200 parts by weight, the decomposition of the rubber asphalt emulsion is accelerated and the pot life is shortened, and the obtained cured product is undesirably low in elongation and unfavorable.

The composition of the present invention is obtained by mixing a rubber asphalt emulsion and the above-mentioned curing agent. It is preferable that the mixing be performed immediately before application using the composition of the present invention in order to form a waterproof coating film.

The mixing method is to add Portland cement, the particle size of which is adjusted according to the requirements specified in the present invention, to the rubber asphalt emulsion.
What is necessary is just to mix.

The composition of the present invention may be mixed with a filler, a thickener, and the like for the purpose of adjusting the viscosity and imparting thixotropic properties.

As the filler, calcium carbonate, magnesium carbonate, gypsum, carbon black, clay, talc, mica powder, white carbon, shirasu balloon, bentonite, diatomaceous earth and the like can be used.

As the thickener, methyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, methyl hydroxyethyl cellulose, ethyl hydroxyethyl cellulose,
Various cellulose derivatives such as methylhydroxypropylcellulose, polyvinyl alcohol, polyethylene oxide, polyacrylamide, sodium polyacrylate, and the like can be used.

In addition, the composition of the present invention includes "CCR slag fine", which is used as an injecting agent when repairing cracks, floating, and the like generated in blast furnace cement, silica cement, fly ash cement, or cement mortar or concrete structures. Fine particle cements such as (Nitto Chemical Industry Co., Ltd.), "MCR Armor # 600" (Mitsubishi Mining Cement Co., Ltd.) and "AR slurry" (Nippon Cement Co., Ltd.) can also be added.

As a method of forming a coating film using the composition of the present invention, the coating can be applied to the base surface using a trowel, a brush, a roller, or the like. Further, spray coating using an air gun or an airless gun with compressed air is also possible.

〔The invention's effect〕

 The effects of the present invention are as follows.

1) The time required for curing the coating film of the composition of the present invention is low in temperature dependency, and the coating film is cured within a relatively short time regardless of the season.

2) The pot life required for the coating operation can be secured for 60 minutes or more.

3) Even if the coating film is thickened, the coating film is uniformly cured, and the occurrence of cracks can be prevented.

4) The formed cured coating film has a high elongation at the time of pulling, improves the followability when a crack occurs on the base, and can prevent the coating film from breaking.

〔Example〕

Next, the present invention will be specifically described with reference to Examples and Comparative Examples. Hereinafter, “parts” means “parts by weight”, and the quantitative ratios indicate weight ratios.

Examples 1-3 and Comparative Examples 1-2. Commercial ordinary Portland cement (Brain value: 3200c
m ² / g) was finely pulverized and subjected to a classification treatment to adjust the particle size, and the ordinary Portland cement (particle size adjusted product) shown in Table 1 having the requirements of the present invention was compared with Therefore, various commercially available Portland cements as they were, or pulverized ordinary Portland cements having a Blaine value of 6500 cm ² / g (before classification treatment) obtained by finely pulverization were tested as curing agents.

Rubber asphalt emulsion (trade name “Emulcoat” manufactured by Nishun Chemical Industry Co., Ltd .; solid content <styrene butadiene rubber-straight asphalt>: 70%, styrene butadiene rubber content 30% in solid content, asphalt content 70%), That
Various Portland cements shown in Table 1 were mixed in a quantitative ratio of 55 parts per 100 parts, and the curing time at a temperature of 40 ° C was measured.

The curing time of each of the obtained compositions was measured by a bigger needle device based on JIS R5201 using a small ring needle attached to a standard termination needle as an intrusion needle.

Each composition in a cement paste container, 20mm each
, And liquid paraffin was flowed over the surface of each composition to prevent drying.

The time when the needle no longer penetrated the composition by 1 mm or more with the passage of time was regarded as the termination, and the time from the time when the rubber asphalt emulsion was mixed with the curing agent to the termination was defined as the curing time.

Each cured product obtained by mixing the various portland cements shown in Table 1 at a quantitative ratio of 60 parts per 100 parts of the rubber asphalt emulsion was subjected to a heat treatment (temperature: 70 ° C. × 70 ° C.) in accordance with JIS A6021. 168 hours), then temperature 20
A tensile test was performed at ℃ to measure the elongation at break.

 The test results are shown in Table 1.

As shown in Table 1, the compositions obtained when Portland cement (granule size-adjusted product) having the requirements of the present invention were used as a hardening agent, all of which had a high hardening rate and a high hardening speed of 40%.
It cured within hours, and the elongation of the cured product showed a value exceeding 1000%. (Examples 1-3). On the other hand, the compositions obtained when using various commercially available Portland cements as they are, or when using ordinary Portland cement pulverized products (before classification treatment), all require 40 hours or more for curing, and The elongation was small. (Comparative Examples 1-3). In general, when a composition obtained by mixing a rubber asphalt emulsion and a hydraulic inorganic substance is left in the air,
Due to the evaporation of water, a dry film is formed on the surface layer in contact with the air in a short time of about 1 to 2 hours. However, it takes a longer time for the entire composition to cure.

As shown in the above-described test method for curing time, the curing time described herein is not the time until a dry film is formed on the surface portion of the composition, but is required for curing the entire composition. Indicates time.

Examples 4 to 9 and Comparative Examples 4 to 5. The same type of rubber asphalt emulsion and the same hardener as used in Example 2 were used, and 100 parts of the rubber asphalt emulsion was used.
The curing agents were added and mixed at the ratios shown in the table, and the obtained compositions were tested in the same manner as in Example 2. The results are shown in Table 2.

When the amount ratio of the curing agent to the rubber asphalt emulsion was within the range specified in the present invention, the rubber asphalt emulsion was not decomposed, and both the cured film and the elongation of the cured product were good. (Examples 4 to 9). On the other hand, when the amount ratio of the curing agent to the rubber asphalt emulsion is less than 10 parts which is out of the range specified in the present invention, the elongation of the cured product is large, but it takes a long time to cure the coating film (Comparative Example 4). On the other hand, when the amount ratio of the curing agent exceeded 200 parts, the rubber asphalt emulsion was decomposed when the mixture was stirred and mixed, so that the rubber asphalt emulsion could not be applied even with a trowel. (Comparative Example 5). Examples 10 to 15. Using the same type of rubber asphalt emulsion and the same curing agent as used in Example 2, 50 parts of a curing agent was added to and mixed with 100 parts of the rubber asphalt emulsion, and the amounts shown in Table 3 were further added. Tests were conducted in the same manner as in Example 2 for various compositions obtained by blending various fillers, thickeners or fine particle cements in the same ratios, and the results are shown in Table 3.

As shown in Table 3, the composition of the present invention has a filler,
Even when the thickener or the fine particle cement was blended, the curing speed was not delayed, and the elongation of the cured product was good.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C09D 1/06 C09D 1/06 195/00 195/00 C09K 3/18 101 C09K 3/18 101 E04D 7/00 E04D 7/00 (72) Inventor Shunsuke Tazawa 10-1 Oguro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside the Central Research Laboratory of Nitto Chemical Industry Co., Ltd. Inside the research institute (72) Inventor Yukihiro Sugano 272 Shiba, Kokubunji-cho, Shimotsuga-gun, Tochigi Prefecture Inside the Technical Research Institute (72) Inventor Yoshiyuki Nagasaka 272 Shiba, Kokubunji-cho, Shimotsuga-gun, Tochigi Prefecture Technology Inside the research institute (72) Inventor Hiroshi Asada 4-3-1, Kudankita, Chiyoda-ku, Tokyo Nichihari Chemical Industry Co., Ltd.Examiner, Kunihiko Sato (56) References JP-A-2-175646 (JP, A) JP-A-1-226756 (JP, A) JP-A-63-236741 (JP, A) JP-A-2-1966051 (JP, A) JP-A-2-208252 (JP) , A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 95/00 C08L 21/00 C04B 24 / 26,24 / 36,28 / 04 C09K 3/18 E04D 7/00 C09D 1 / 06 C09D 195/00

Claims (1)

(57) [Claims] 1. A composition comprising a rubber asphalt emulsion and a cement as a hardening agent, wherein the hardening agent has a Blaine value of at least 6500 cm ² / g and a content of particles having a diameter of more than 5 μm of 40% by weight. % Of Portland cement, less than 100% of rubber asphalt emulsion.
A rubber asphalt waterproofing composition obtained by mixing the curing agent in an amount of 10 to 200 parts by weight per part by weight.