JPS5938990B2 - curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improving the properties of curable compositions comprising bituminous emulsions and water-soluble polyisocyanate compounds, in particular to reduce the inherent tendency of foaming.

A water-soluble polyisocyanate compound obtained by reacting a bitumen emulsion with 1 mole or more of a polyisocyanate compound per hydroxyl group of a water-soluble compound having two or more terminal IC hydroxyl groups (hereinafter simply referred to as a water-soluble prepolymer) It is known that they can be mixed and used as waterproofing materials, covering materials, water-stopping materials, and grouting materials.

This is because when a bituminous emulsion and a water-soluble prepolymer are mixed, the water-soluble prepolymer is dissolved or dispersed in the aqueous phase of the bituminous emulsion, and then reacts with water and polymerizes, creating a three-dimensional network structure of polyurethane and turning the entire mixture into a gel-like substance. This technology takes advantage of the property of decomposing bitumen emulsion and forming a waterproof, rubber-like elastic cured product made of bitumen and polyurethane. However, it has been found that this type of cured product has disadvantages in that when immersed in alkaline water for a long period of time, the physical properties of the cured product deteriorate or the cured product breaks apart and disperses in the water. Additionally, when the water-soluble prepolymer reacts with the water in the bitumen emulsion during curing, carbon dioxide gas is generated, which causes air bubbles to form in the cured product, resulting in a decrease in physical properties and weather resistance. . The present invention aims to solve these problems, and the present invention has a curable material that can be applied to waterproofing, coating, waterproofing, grouting, etc. by reducing the inherent foaming and obtaining a cured product with excellent water resistance and chemical resistance. It is intended to provide a composition.

That is, the present invention provides 100 parts by weight of a cemented bitumen emulsion containing 0.1 to 1.5% by weight of cement in the bitumen emulsion;
A curable composition comprising 3 to 15 parts by weight of a water-soluble polyisocyanate compound obtained by reacting one hydroxyl group of a water-soluble compound having two or more hydroxyl groups at the terminal with 1 mole or more of a polyisocyanate compound. This is related to.

The bitumen emulsion used in the present invention contains one or more of petroleum asphalts such as straight asphalt, blown asphalt, cutback asphalt, and propane-deasphalt, heavy oil, natural asphalts, tars, and pitches. The mixed bituminous material is processed using a colloid mill, homogenizer, etc. using various surfactants such as cationic, nonionic, and anionic, one or more emulsifiers such as clay, acids, alkalis, salts, protective colloids, etc. It is a bitumen emulsion emulsified in water using a suitable emulsifying machine such as a homomixer.

Furthermore, bituminous emulsions that are obtained by emulsifying bituminous materials modified by adding natural rubber, synthetic rubber, thermoplastic polymer polymer resin, synthetic resin, natural resin, etc. to the above-mentioned bituminous materials are also used in the present invention. include.

Furthermore, the bituminous emulsions and modified bituminous emulsions mentioned above to which latexes and emulsions such as natural rubber, synthetic rubber, synthetic polymer resins, synthetic resins, and natural resins are added may also be used in the present invention. Contained in emulsion. Furthermore, resins, oils, process oils, plasticizers, There are cases where fatty acids, resin acids, naphthenic acids, fatty acid amides, fatty amines, alkylphenols, metal soaps, anti-aging agents, etc. are added, and anti-aging agents and other substances are added to the bitumen emulsion. The bitumen emulsion prepared by the above method can also be used as the bitumen emulsion used in the present invention.

Examples of the rubber and synthetic polymer resin used in the bituminous emulsion used in the present invention are as follows.

Natural rubber, chlorinated rubber, cyclized rubber, isoprene rubber, styrene-butadiene rubber, styrene-isoprene rubber, chloroprene rubber, butyl rubber, halogenated butyl rubber, nitrile rubber, ethylene propylene rubber, chlorinated polyethylene rubber, chlorinated polypropylene, chlorsulfone polyethylene, styrene-butadiene block polymer, styrene-isoprene block polymer, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, polyvinyl chloride, polyacrylate, acrylate-vinyl acetate copolymer, ethylene acrylate copolymer These include polymers, acrylate-styrene copolymers, acrylate-butadiene-styrene copolymers, polyvinylidene chloride, and polyurethane. The bitumen emulsion used in the present invention described above must not decompose even if a small amount of cement is added and mixed. Also, the amount of evaporation residue is usually 50-70% by weight? are used.

The cement used in the present invention is a cement such as Portland cement, fly ash cement, blast furnace cement, blast furnace colloidal cement, colloidal cement, silica cement, dinit cement, alumina cement, etc.

Furthermore, an inert inorganic filler may be added together with the cement. The bitumen emulsion containing cement (hereinafter referred to as cement-containing bitumen emulsion) used in the present invention is a mixture of 0.1 to 1.5 parts by weight of cement to 100 parts by weight of the bitumen emulsion. It is.

Although it depends on the type of cement, it is generally best to wait at least 12 hours, preferably 24 hours or more, after adding cement to the bitumen emulsion. When the curable composition of the present invention is cured for 24 hours or more, almost no foaming phenomenon is observed, and the alkali resistance and chemical resistance of the cured product are significantly improved.

This effect remains the same even after one month or more has passed after the addition of cement, or the effect is not sufficiently exerted immediately after the addition of cement. Cement-containing bitumen emulsion is made by dispersing cement in an emulsion when producing bitumen emulsion.
It can also be made by passing an emulsion in which bitumen and cement are dispersed through an emulsifying machine.

Such a bituminous emulsion containing cement can also be used in the present invention, and the proportion of cement used and the amount of cement added are also the same. The proportion of cement in the bituminous emulsion containing cement used in the present invention is effective only within a very narrow range of 0.1 to 1.5 parts by weight of cement per 100 parts by weight of bituminous emulsion.

When the amount of cement is less than 0.1 part by weight, the effect of suppressing foaming during curing of the curable composition and the effect of improving alkali resistance and chemical resistance in the physical properties of the cured product after curing are no longer significant. Conversely, when the amount of cement exceeds 1.5 parts by weight, the curable composition tends to not harden. The water-soluble prepolymer that can be used in the present invention is a water-soluble prepolymer obtained by reacting a water-soluble compound having two or more hydroxyl groups at the end with 1 mole or more of a polyisocyanate compound per hydroxyl group. be.

This is a water-soluble compound (hereinafter referred to as a polyalkylene oxide compound) having two or more hydroxyl groups at the end and a polyoxyalkylene chain with a molecular weight of about 300 to 20,000, and the same molar amount as the hydroxyl group. It is obtained by reaction with several or more polyisocyanate compounds. The above-mentioned polyalkylene oxide compound is a compound having two or more hydroxyl groups at the terminal obtained by subjecting a compound having active hydrogen to a long chain addition reaction of alkylene oxide.

In addition, compounds having active hydrogen include polyols such as ethylene glycol, glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, seuclose, and methyl glucotide;
Amines such as ethylenediamine, diethylenetriamine, methylamine, carboxylic acids such as castor oil, tall oil, rosin acid, and aldehydes and other compounds such as
There are compounds having two or more hydroxyl groups obtained by the reaction of olefins, aromatic hydrocarbons, etc.).
Compounds obtained by addition-reacting mainly ethylene oxide and secondarily other alkylene oxides to these active hydrogen-containing compounds, or mixtures thereof, exhibit excellent water solubility and are difficult to react with polyisocyanate compounds. It is desirable that the prepolymer thus obtained has a polyalkylene oxide chain of a length that does not impair water solubility or dispersibility, or it can be similarly prepared by adding a dispersant, solubilizer, etc. It is necessary to select a range of polyalkylene oxide chains and molecular weights that can impart these properties.

In the present invention, the reaction ratio in the synthesis of the prepolymer is 2 to 20 mol (weight) of the polyisocyanate compound to 1 mol (weight) of the polyalkylene oxide compound; It is selected depending on the number of hydroxyl groups in the molecule.

This is determined within a range in which the molecular weight of the prepolymer obtained as a result of the reaction does not impede water solubility. The polyisocyanate compound used in the present invention is a compound having two or more isocyanate groups based on an organic compound.

Examples include diisocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate, diphenyl diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, etc., and triisocyanate compounds such as triphenylmethane triisocyanate. The alkylene oxides used in the present invention include ethylene oxide (hereinafter referred to as EO), propylene oxide (hereinafter referred to as PO), butylene oxide, styrene oxide, and epichlorohydrin.

The water-soluble prepolymer mixed in the cement-containing bitumen emulsion in the present invention is prepared by mixing the above-mentioned polyalkylene oxide compound and polyisocyanate compound in the above-mentioned ratio,
It can be easily obtained by reacting at room temperature to 100° C. or lower for a certain period of time.

When these water-soluble prepolymers are mixed with water, they dissolve or are dispersed in a colloidal form close to a solution. Next, it reacts with water and hardens to form an elastic body. In order to prevent the water-soluble prepolymer from dissolving or dispersing in water, a water-soluble solvent such as methyl ethyl ketone (MEK) is added to the water-soluble prepolymer.
It can also be used in addition. Such water-soluble prepolymers are also used in the present invention. Good results can be obtained by mixing 3 to 15 parts by weight of the water-soluble prepolymer (in terms of non-volatile content) per 100 parts by weight of the bituminous emulsion containing cement.

If the amount is less than 3 parts by weight, the curability of the curable composition is poor and it is difficult to form a homogeneous elastic body.

If the amount exceeds 15 parts by weight, the reaction between the water-soluble prepolymer and water will be rapid, and the effect of suppressing foaming during hardening with cement will not be sufficiently exerted, and air bubbles will tend to remain in the hardened product. It has disadvantages such as causing large blisters. The curable composition of the present invention is usually supplied in a two-component form consisting of a bituminous emulsion containing cement and a water-soluble prepolymer.

When used, both are mixed at a predetermined mixing ratio.
For example, in waterproofing, a cement-containing bitumen emulsion and a water-soluble prepolymer are mixed and sprinkled or coated on the substrate to be waterproofed before it hardens. The water-soluble prepolymer reacts and cures within a short time, converting the entire curable composition into a gel-like elastomer.
The cemented bitumen emulsion itself then decomposes either immediately or over time. The curable composition of the present invention thus obtained is cured with no or almost no foaming, and furthermore becomes an elastic body with excellent alkali resistance and chemical resistance. Since the water-soluble prepolymer reacts quickly with water, the cement-containing bituminous emulsion and the water-soluble prepolymer should be mixed by a method that mixes the two liquids during spraying, or by spraying using a device directly connected to the mixing spray. It is also suitable to adopt a method such as Next, the effects of the curable composition of the present invention will be explained.

(1) The curable composition of the present invention cures without foaming during curing.

When the curable composition is mixed and cured, a cured product without foaming can be obtained even if the curable composition is cured not in a thin film but in a thick layer, for example in a pot. In order to find out whether carbon dioxide gas, which is supposed to be generated when a water-soluble prepolymer reacts with water, is not generated or is generated and absorbed by the alkali, we investigated a bituminous emulsion containing slaked lime using slaked lime instead of cement. When curing was performed using a combination of slaked lime and a water-soluble prepolymer, it was found that when the amount of slaked lime was large, it did not harden, and when the amount of slaked lime was small, it hardened, but foaming could not be suppressed. Bituminous emulsion with cement, narrow range of cement amount from 0.1 to 1.5
The fact that it is effective in a range of weight percent, and moreover, it is more effective when 24 hours or more have elapsed from immediately after adding cement to the bitumen emulsion, clearly indicates that cement is not just an effect as a filler, but as a curable composition. This is thought to have a large effect on the reaction system.

(2) The cured product of the curable composition of the present invention has significantly improved alkali resistance, acid resistance, water resistance, etc. compared to the conventional cured product made of bituminous emulsion and water-soluble prepolymer without adding cement. It was done.

The cured product of the curable composition of the present invention does not deteriorate even when immersed in an alkaline aqueous solution such as a 5% caustic soda aqueous solution, a 10% slaked lime aqueous solution, or cement exudate water for a long period of time, but is soluble in water compared to a conventional cement-free bitumen emulsion. The cured product with the prepolymer tends to dissolve or disperse or become crumbly when immersed for a long period of time. The cured product of the curable composition of the present invention is also excellent in water resistance and acid resistance. This fact and the fact that the above-mentioned foaming does not occur suggests that the cement greatly contributes to the curing reaction system of the curable composition, and the mechanism of this reaction is still under investigation. The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples.

In addition, the method for measuring density, the method for measuring fineness, and the method for testing chemical resistance in Examples and Comparative Examples were as follows.

(1) Density measurement method Add a predetermined amount of water-soluble prepolymer to cement-containing bituminous emulsion or bituminous emulsion 1509, mix for about 1 minute, and then measure the volume in a pot-shaped polystyrene container (upper rim inner diameter 6.5 CIrL1). Bottom inner diameter 4.5cm 1 height 9C
Weigh out about 1009 on a TIL) and harden it at room temperature to give 24
After leaving it for a while, put glass beads with a diameter of about 0.2 mm flat to the edge into a polystyrene container, weigh the total weight, then weigh the glass beads, and calculate the cured product from the volume. The density of the cured body is calculated by determining the volume and dividing the weight of the cured body by the volume.

If there is no foaming in the cured product, the specific gravity of the cured product is almost 1,
If there is foaming, the specific gravity will be less than 1, and the more foaming, the lower the specific gravity. (2) Method for measuring penetration The sample after density measurement was placed in a constant temperature oven at 25℃ for 2 hours.
After curing for an hour, immediately test the penetration at 25°C, 100!9, 5 seconds in accordance with the JIS K253O penetration test in air (without soaking in water) in a constant temperature room at 25°C. Measure.

The unit is 1/100CTL. (3) Test method for chemical resistance Add a specified amount of water-soluble prepolymer to bituminous emulsion containing cement or bituminous emulsion, mix for 1 minute, and then harden on a horizontal plate covered with release paper to a thickness of about 5 mm. After curing the sheet-like material in air at room temperature for 3 days, it became about 21.
50fL×17.5? The sample was cut into a size of 1, used as a test piece, weighed, immersed in various chemical solutions, and observed and measured changes in appearance and weight over the number of days of immersion.

In addition, the weight change rate was determined by setting the weight before immersion as 100.
Example 1 Bituminous emulsion containing 1% cement and bituminous emulsion containing 0.5% cement: Asphalt emulsion for mixing cement (manufactured by Nichirei Kagaku Kogyo Co., Ltd., evaporation residue 60% by weight, evaporation residue penetration 1)
80) 100 parts by weight of ordinary Portland cement
Add 0.5 parts by weight or 0.5 parts by weight and mix thoroughly.
It was obtained by leaving it for several days.

Water-soluble polyisocyanate compound (water-soluble prepolymer): Hycel 0HIA (manufactured by Toho Chemical, trade name) bituminous emulsion containing 1% cement or 0.5% bituminous emulsion of cement 1509 and water-soluble prepolymer in various ranges from 2 to 209. After mixing for 1 minute, the cured product was poured into a polystyrene container and cured. After curing the cured product at room temperature (approximately 2°C) for 24 hours, the density and penetration were measured.

These results are shown in FIG. Comparative Example 1 For comparison, asphalt emulsion for cement mixing or cationic asphalt emulsion (JISK
22O8PK-1 equivalent product, evaporation residue 56 weight? The water-soluble prepolymer used in Example 1 was mixed in the same manner as in Example 1, and the density and penetration of the cured product were measured.

The results are shown in FIG. 1 as in Example 1. As is clear from FIG. 1, the examples using cement-containing bitumen emulsions have high density and very little foaming, but the bituminous emulsions without cement have large nonionic and cationic foams and low density.

It can also be seen that the foaming increases as the amount of water-soluble prepolymer added increases. Example 2 and Comparative Example 2 The same bituminous emulsion containing cement as in Example 1 (2 types) The same bitumen emulsion (2 types) as in Comparative Example 1 was used.

The temperature of each emulsion was maintained at 50°C, and these emulsions 1509
2 to 20 g of the water-soluble prepolymer used in Example 1
Various amounts were added within the range of 1, mixed for 1 minute, and cured in the same manner as in Example 1. The density and penetration of the obtained cured product were measured. These results are shown in FIG. In addition, in the case of using a cationic asphalt emulsion, scattering during curing was so severe that neither density nor penetration could be measured. As is clear from FIG. 2, the effect of suppressing foaming of the cured product by the addition of cement is remarkable, and is effectively exhibited without being lost even at high emulsion temperatures. Example 3 In order to see the effect of the amount of cement added on the curable composition, 0.1% by weight of ordinary Portland cement was added to the asphalt emulsion for cement mixing used in Example 1.
(Outside %) 1.5 weight in increments? Addition-mixed emulsions were made, and after 7 days, 150 emulsions were prepared for each of these emulsions.
The water-soluble prepolymer 109 used in Example 1 was added to and mixed with Example 9, and the resultant cured product was cured in the same manner as in Example 1, and the density and penetration were measured.

Experiments were conducted at room temperature (approximately 2'C). The results of these tests are shown in FIG. Example 4 Chemical Resistance Test For each of the four emulsions used in Example 1 and Comparative Example 1, 150 parts by weight of the emulsion and 10 parts by weight of Hicel 0H1A were added and mixed and cured into a sheet with a thickness of approximately 5 mm. A chemical resistance test was conducted by immersing it in various chemical solutions.

These results are shown in Table 1. Regarding water, 5% hydrochloric acid, and 5% sulfuric acid, the weight change of the cured products using the four types of emulsions was large, but there was no abnormality in appearance.In other words, the weight change rate of the cured products using the cement-containing emulsion was small. be.

5% caustic soda aqueous solution, 10% slaked lime aqueous solution, and 1
In the case of a 0% cement aqueous solution, although there was a weight change in the cured product using the cement-containing emulsion, no embrittlement was observed and there was no abnormality in appearance.

Both the cement mixing emulsion to which no cement was added and the cured product using the cationic emulsion became brittle and either fell apart or dissolved. Example 5 Cationic asphalt emulsion for cement mixing (evaporation residue: 60 weight? Penetration of evaporation residue: 115) 90 parts by weight, neoprene latex #950 (product name: cationic chloroprene rubber latex manufactured by Dupont) 10 parts by weight 1 part by weight of early-strength Portland cement was added to the well-mixed mixture, mixed thoroughly, and left for one day and night.

Hycel 0H1 to 100 parts by weight of this cement-containing emulsion
A mixture containing 10 parts by weight of A was cured. The cured product hardly foamed and had good alkali resistance, water resistance, and acid resistance. Example 6 Coal tar pitch 30 parts by weight, anhydrous coal tar
Heat and melt 70 parts by weight, add 5 parts by weight of nitrile rubber latex (nonvolatile content 40% by weight),
Raise the temperature to 0℃ to volatilize water to create rubber-containing tar, which is then emulsified to create Menion tar emulsion (non-volatile content).
55% by weight).

Add 1% by weight of ordinary Portland cement to this emulsion (excluding %
) was added, thoroughly mixed, and left for 7 days. 100 parts by weight of this cement-containing tar emulsion and Hycel 0H1A8
Parts by weight were added and mixed.

This product cured after 15 minutes, but there was almost no foaming during curing, and when the cured product was subjected to an alkali resistance test, good results were obtained. The curable composition of the present invention is
There is almost no foaming during curing, and the chemical resistance of the cured product has been significantly improved, making it more durable, making it suitable for use in conventional waterproofing materials, covering materials, water-stopping materials, and grouting materials. We are confident that not only the applicability will be further expanded, but also other new uses will be developed.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the density and penetration of the cured products obtained in Example 1 and Comparative Example 1.

Claims (1)

[Claims] 1 100 parts by weight of a cemented bitumen emulsion containing 0.1 to 1.5% by weight of cement in the bitumen emulsion, and 2 parts by weight at the end.
A curable composition comprising 3 to 15 parts by weight of a water-soluble polyisocyanate compound obtained by reacting 1 mole or more of a polyisocyanate compound with one hydroxyl group of a water-soluble compound having 1 or more hydroxyl groups.