JPH0450267A - Rubber asphalt-based water-proofing composition - Google Patents

Abstract

PURPOSE:To obtain the subject water-proofing composition having low temperature dependence and capable of producing a stable thickness in a relatively short time by blending a rubber.asphalt emulsion with a curing agent composed of alumina cement and a hydraulic cement in a specified ratio. CONSTITUTION:With (A) a rubber-asphalt emulsion composed of (i) a rubber such as butadiene rubber and (ii) an asphalt such as straight asphalt, (B) a curing agent composed of (iii) 1 pt.wt. alumina cement and (iv) 0.2-99 pts.wt. hydraulic cement is blended in a ratio of 10-2300 pts.wt. component (B) to 100 pts.wt. component (A), thus giving the objective water-proofing composition capable of producing a stable thickness free from generation of cracks.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rubber-asphalt waterproofing composition. Specifically, the present invention relates to a rubber asphalt waterproofing composition that is used in civil engineering and construction waterproofing methods, particularly asphalt waterproofing room temperature construction methods, and is capable of forming a stable thick film in a relatively short period of time.

[Conventional technology]

Conventionally, asphalt waterproofing and thermal construction methods, sheet waterproofing and coating waterproofing methods have been used as waterproofing methods for civil engineering and construction, but most of them are based on asphalt waterproofing and thermal methods in terms of reliability, waterproofing, durability, etc. Currently, the construction method is being adopted. However, with this thermal construction method, the asphalt must be heated and melted at the construction site, which poses a risk of burns and may cause a fire at construction sites where there are many flammable materials. There is a distance between. Furthermore, when asphalt is heated and melted, odor and smoke are generated, which causes environmental pollution and is likely to become a pollution problem in urban areas.

In place of this, in recent years, an asphalt waterproofing method using rubber asphalt emulsion at room temperature has been adopted. In this construction method, a hydraulic inorganic substance such as cement is used to harden the rubber asphalt emulsion. This is to cure rubber asphalt by using the water present in the rubber asphalt emulsion as water for the hydration reaction of hydraulic inorganic substances.

Methods of using hydraulic inorganic substances to harden rubber asphalt emulsions include a method of using Portland cement alone (Japanese Unexamined Patent Publication No. 16070/1982), and a method of using a combination of alumina cement and gypsum (Japanese Unexamined Patent Publication No. 16070/1983). Publication No. 158269/1982) and the like have been proposed.

[Problem to be solved by the invention]

In the method described in JP-A-57-16070, in which Portland cement is used alone as a hydraulic inorganic substance, the coating film curing speed is slow and a sufficient degree of coating film curing cannot be obtained in a short period of time. The problem is that the speed changes greatly depending on the temperature. Furthermore, in the case of thick coating, there is a problem that the difference in curing speed between the surface and the inside of the coating film becomes large, and cracks are likely to occur in the formed coating film.

In addition, in the method of using a combination of alumina cement and gypsum as a hardening agent for a rubber asphalt emulsion described in JP-A-60-158269, the temperature dependence of the coating film curing rate is small, and the crystallization water of the hydrate is Although it is excellent in removing moisture from the rubber asphalt emulsion because of its large amount, it has the problem that the complete curing speed of the coating film is slow and it takes 3 to 4 days even at room temperature for the coating film to be completely cured.

[Means to solve the problem]

The inventors of the present invention have conducted extensive research to improve the above-mentioned problems, and have found that a composition obtained by combining a rubber asphalt emulsion, alumina cement, and hydraulic cement in a specific range of ratios has sufficient potency. We learned that it can be used for a long time and cures in a short time even in a wide temperature range from low to high temperatures, and that it can form a stable thick film that does not cause cracks when applied. , based on this knowledge, completed the present invention.

That is, the present invention provides ``a composition in which a rubber asphalt emulsion is mixed with cement as a hardening agent, in which the hardening agent contains 0 hydraulic cement per 1 part by weight of alumina cement.
．． 2 to 99 parts by weight of a rubber asphalt-based waterproofing composition, in which the curing agent is mixed in an amount of 10 to 200 parts by weight per 100 parts by weight of a rubber asphalt emulsion. This is the summary.

The present invention will be explained in detail below.

The rubber asphalt emulsion used in the rubber asphalt waterproof 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 cationic, nonionic, or amphoteric. However, it is preferable to add and mix alumina cement and hydraulic cement (hereinafter collectively referred to as hardening agent) to maintain stability during the coating operation.

Examples of rubbers used in rubber asphalt emulsions include:
Styrene-butadiene rubber, carboxy-modified styrene-
Butadiene rubber, acrylonitrile-butadiene rubber,
Examples include methyl methacrylate-butadiene rubber, polybutadiene rubber, butyl rubber, isoprene rubber, chloroprene rubber, natural rubber, and styrene-butadiene rubber or carboxy-modified styrene-butadiene rubber is particularly preferred.

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

Each of the above-mentioned rubber and asphalt can be used alone or in combination of two or more kinds.

The rubber asphalt emulsion may be prepared by a conventional method. Generally, an emulsion is prepared by first adding a surfactant and a stabilizer to warm water and stirring until completely dissolved. This emulsion and heated molten asphalt are mixed and emulsified using a colloid mill, homogenizer, etc.

The surfactants include aliphatic amines, aliphatic diamines, aliphatic triamines, aliphatic amidoamines, aliphatic imidacillins or derivatives thereof, quaternary ammonium salts, amines having a heterocyclic nitrogen group, and other cationic surfactants. Or amphoteric surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, oxyethylene-oxypropylene floc copolymer, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid,
Glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkylamine, alkyl alkanolamide and other nonionic surfactants can be used.

As the stabilizer, those that form a hydrophilic sol in water, such as sodium alginate, starch, gelatin, carboxymethyl cellulose, methyl cellulose, and polyvinyl alcohol, are used.

The solids content of the rubber asphalt emulsion is preferably in the range of 50 to 85% by weight; if it is less than 50% by weight, the amount of curing agent required increases, and the resulting cured product has little elongation and becomes sluggish. On the other hand, if it exceeds 85% by weight, it becomes difficult to add a curing agent.

The ratio of rubber to asphalt in the rubber asphalt emulsion is not particularly limited, but from a performance standpoint
It is preferable that the weight ratio of asphalt is in the range of 20/80 to 50/50.

The alumina cement used as a curing agent in the composition of the present invention may be Ca0-A1.03 and/or 12
Ca0・7Al□0. It is preferable that the main component is

Further, the hydraulic cements used as a hardening agent in the composition of the present invention include ordinary Portland cement, early strength Portland cement, ultra early strength Portland cement, moderate heat Portland cement, sulfate resistant Portland cement, high iron oxide type Portland cement, white Portland Cement Blast Furnace Cement, Silica Cement, Friance Cement, Masonry Cement, Die/To Cement, and rCCR Slag Fine'' (Nitto Chemical Industry ■
(manufactured by Nippon Cement), rMCR Armor-600J (manufactured by Mitsubishi Mining Cement ■), and rAR Slurry (manufactured by Nippon Cement ■). It is preferable to use at least one type of these hydraulic cements, and to use two or more types in combination.

In the present invention, the ratio of alumina cement and hydraulic cement used as a hardening agent for the rubber asphalt emulsion is 0 parts by weight of alumina cement and 0 parts by weight of hydraulic cement.
．． It ranges from 2 to 99 parts by weight, preferably from 0.3 to 70 parts by weight. When the amount is less than 0.2 parts by weight or more than 99 parts by weight, the hydration reaction is slow and the curing speed of the rubber asphalt emulsion cannot be accelerated.

The amount ratio of the curing agent to the rubber asphalt emulsion in the composition of the present invention is such that the sum of alumina cement and hydraulic cement is 10 to 100 parts by weight of the rubber asphalt emulsion.
It is in the range of 200 parts by weight, preferably in the range of 15 to 160 parts by weight, more preferably in the range of 20 to 140 parts by weight. If the amount is less than 10 parts by weight, it will take a long time to cure the rubber asphalt emulsion and the desired degree of curing will not be achieved. Therefore, the pot life tends to be shortened. 200
If the amount exceeds 1 part by weight, the rubber asphalt emulsion decomposes prematurely, shortening its pot life, and the obtained cured product has low elongation and becomes brittle, which is not preferable.

The composition of the present invention is obtained by mixing a rubber asphalt emulsion and the curing agent. The mixing period is preferably carried out immediately before application using the composition of the present invention in order to form a waterproof coating film.

Regarding the mixing method, alumina cement and hydraulic cement may be added individually to the rubber asphalt emulsion, but it is preferable to mix the alumina cement and hydraulic cement in advance and then add them to the rubber asphalt emulsion. .

The composition of the present invention may be mixed with aggregates, fillers, thickeners, etc. for the purpose of adjusting its viscosity and imparting thixotropy during application.

Aggregates include mountain sand, river sand, sea sand, silica sand, crushed artificial lightweight aggregate, and fillers include calcium carbonate, magnesium carbonate, clay, and talc.

Carbon black, mica powder, perlite, fuyolite, white carbon, shirasu balloon.

Short fibers such as bentonite, diatomaceous earth, and natural fibers and synthetic fibers can be used.

In addition, as for the thickening side, various cellulose derivatives such as methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, methylhydroxyethylcellulose, ethylhydroxyethylcellulose, methylhydroxypropylcellulose, polyvinyl alcohol, polyethylene oxide, polyacrylamide, polyacrylic acid Soda etc. can be used.

As a method for forming a coating film using the composition of the present invention, it can be applied to the underlying surface using a trowel, a spatula, a roller, or the like. It is also possible to apply by spraying using an air gun or an airless gun using compressed air.

〔Effect of the invention] 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 has low temperature dependence, and the coating film is cured within a relatively short time regardless of the season.

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

3) Even if the coating film is made thicker, the coating film will harden uniformly and cracks can be prevented.

(Examples) Next, the present invention will be specifically explained with reference to Examples and Comparative Examples. Hereinafter, "parts" means "parts by weight", and quantitative ratios represent weight ratios.

Examples 1 to 10 and Comparative Examples 1 to 7 Rubber asphalt emulsion (manufactured by Nichirei Kagaku Kogyo ■, trade name "Emulcoat"; solid content styrene butadiene rubber - straight asphalt) = 70%, solid content styrene butadiene A mixture of alumina cement and early-strength Portland cement, which is a hydraulic cement, shown in Table 1 at a ratio of 35 parts per 100 parts (rubber content: 30%, asphalt content: 70%), and for comparison, each were added individually and mixed.

After mixing, the viscosity of each of the obtained compositions was measured using a BM type viscometer and used as a guideline for pot life.

In addition, each of the obtained compositions was applied to a commercially available concrete sidewalk board (300x300x35cm) at a thickness of 4cm,
The degree of curing of the formed coating film after 16 hours is the first
Judgment was made using the classification criteria shown in the table.

Table 1.

Table 2.

The curing time of each of the obtained compositions was measured using a Vigor needle device in accordance with JIS R5201, using a small ring needle attached to a standard termination needle as an intrusion needle.

Pour each composition into a cement paste container, 20 cm each.
liquid paraffin was poured over the surface of each composition to prevent drying.

The curing time was defined as the time when the needle no longer penetrated into the composition by more than 1 inch over time, and the curing time was defined as the time from the time when the rubber asphalt emulsion and the curing agent or each cement alone were mixed until the end of curing.

The test results conducted at temperatures of 5°C, 20°C and 40°C are shown in Table 2.

As shown in Table 2, in the composition obtained by mixing the rubber asphalt emulsion and the curing agent in the quantitative ratio within the range specified in the present invention, the coating film was The curing speed was fast, and most of the coating films showed a degree of curing of 4 to 5 16 hours after mixing, reaching practical strength at an early stage.

Further, even after 60 minutes had passed after mixing, the composition had a viscosity that allowed spraying and application, and the pot life was maintained for more than 60 minutes.

(Example-1 to IO).

On the other hand, when the quantitative ratio of alumina cement/early strength Portland cement deviates from the range specified by the present invention (Comparative Example-2) or when each cement is mixed alone with rubber asphalt emulsion (Comparative Example-2) -1
, 3 to 7), the curing speed was slow and a sufficient degree of curing could not be obtained.

In general, when a composition obtained by mixing a rubber asphalt emulsion and a hydraulic inorganic substance is left in the atmosphere, the surface layer in contact with the atmosphere will break down in a short period of about 1 to 2 hours due to evaporation of water. A dry film forms. However, it takes a longer time for the entire composition to cure.

As shown in the above-mentioned curing time test method, the curing time described herein is not the time required for a dry film to form on the surface layer of the composition, but the time required for the entire composition to cure. Show time.

Examples 11-16 and Comparative Examples 8-9゜Example-1-1
A mixture of alumina cement/ordinary Portland cement/silica cement (quantity ratio = 1151
0.5) was added and mixed in the quantitative ratio shown in Table 3, and the various compositions obtained were tested at a temperature of 20°C in the same manner as in Example 1, and the results were shown in Table 3. .

When the ratio of the curing agent to the rubber asphalt emulsion was within the range specified by the present invention, there was no decomposition of the rubber asphalt emulsion and the coating film was cured well. (Examples 11-16).

On the other hand, if the amount ratio of the curing agent to the rubber asphalt emulsion is less than 10 parts, which is outside the range specified by the present invention, the coating film is insufficiently cured (Comparative Example 8); When the amount exceeded 200 parts, the rubber asphalt emulsion decomposed during mixing, making it impossible to apply it even with a trowel. (Comparative Example 9).

Examples 17-18 and Comparative Examples 10-14゜Example 1-
Per 100 parts of the same type of rubber asphalt emulsion as used in 10, 50 parts of the following curing agent or each of the various cements shown in Table 4 for comparison were added and mixed, and the resulting composition was heated at a temperature of 45°C. A test was conducted in the same manner as in Example 1. Curing degree of each composition and 7
Table 4 shows the results of observing the state of the coating film after several days.

[Curing agent A]...Mixture of alumina cement/early strength Portland cement/fly ash cement (quantity ratio =
1 / 110.3); [Curing agent B] ... a mixture of alumina cement / jet cement / rCCR slag fine (manufactured by Nitto Kagaku Kogyo ■) (quantity ratio = 1 / l 10.3); Table 4 shows As shown, in the composition of the present invention obtained by combining alumina cement and hydraulic cement with a rubber asphalt emulsion, the cured coating film formed was very good, with no cracks occurring. (Examples 17-18).

On the other hand, in the composition obtained by using each cement alone in the rubber asphalt emulsion, many cracks occurred in the formed cured coating film. (Comparative Examples 1O to 14).

Table 4.

The test was carried out in the same manner, and the results are shown in Table 5.

Examples 19-24゜To 100 parts of the same kind of rubber asphalt emulsion as used in Examples 1-10, a mixture of alumina cement/early strength Portland cement as a hardening agent (quantity ratio -1/10) 3
Temperature 5 for various compositions obtained by adding and mixing 0 parts and further blending various aggregates, fillers, or thickeners.
℃ as in Example 1 (polyethylene oxide) As shown in Table 5, even if aggregate, filler, and thickener are added to the composition of the present invention, the curing speed is not delayed and is accelerated at an early stage. Achieved practical strength.

Claims (1)

[Claims] In a composition formed by mixing a rubber asphalt emulsion and cement as a hardening agent, the hardening agent is alumina cement 1
It is a combination of 0.2 to 99 parts by weight of hydraulic cement per part by weight, and 10 to 20 parts by weight of the curing agent per 100 parts by weight of rubber asphalt emulsion.
A rubber asphalt waterproofing composition containing 0 parts by weight.