JPH0130863B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-hardening rubber asphalt waterproofing material containing crushed tire rubber that is highly elastic and suitable for coating waterproof layers that can be coated thickly or for injection filling, and particularly relates to a method for solidifying the same. It is.

The "emulsion slow coagulant" mentioned here is one that breaks the emulsion state, separates water, and coagulates slowly, requiring several minutes or more.
Also called a delayed coagulant. For example, sodium silifluoride, potassium silifluoride, formic acid, ammonium formate, magnesium oxalate, iron oxalate, magnesium chloride,
These are magnesium sulfate, iron alum, and aluminum sulfate. (On the other hand, "coagulants" instantly break the emulsion state and separate water. For example, strong acids, calcium chloride, calcium nitrate, cyclohexylamine, etc.) "Spreading agents" are calcium caseinate, Water-soluble polymers such as lignin sulfonate, methyl cellulose, carboxymethyl cellulose, polyhydroxylethyl cellulose, powder, gelatin, rosin soap, and hydrated sulfur vinyl alcohol, which are often used for spraying agricultural chemicals. It is.

Conventionally, there is a waterproof paving material for tennis courts and other surfaces made by mixing asphalt emulsion with rubber powder, but if you apply a thick coat at once, the inside will be difficult to dry and will cause blistering, so you will have to apply it in several thin coats. It requires a lot of manpower and time.

There is also a method of simultaneously spraying a rubber asphalt emulsion and a coagulant (calcium chloride, calcium nitrate, etc.) to instantly form a waterproof coating, but this causes pollution due to the scattering of the rubber asphalt and limits the number of places where it can be applied. Furthermore, it is difficult to form a uniform coating film on protrusions, protruding corners, and inner corners of the base. Also, there is a drawback that if rubber powder is added and sprayed, the coating film becomes porous.

There is also a waterproof layer forming method in which a slow coagulant as mentioned above is mixed with a rubber asphalt emulsion.
As slow coagulants are also called delayed coagulants, coagulation usually begins after a delay of several minutes to several tens of minutes, but once coagulation begins, it hardens rapidly. Moreover, the solidification start time is greatly affected by the temperature, which causes many problems during work. Particularly in this case, if a slow coagulant is added in powder form to an asphalt emulsion mixed with rubber powder, dispersion will be poor and uniform coagulation will not be obtained, and if the slow coagulant is used as an aqueous solution, the coagulation will be too sensitive and the temperature will be too low. The solidification start time is greatly influenced by changes in the temperature, making it difficult to work and making it impossible to obtain a waterproof coating of uniform thickness. Another drawback was that injection filling could not be performed satisfactorily.

The present invention improves the above-mentioned conventional drawbacks, and provides a highly elastic rubber asphalt waterproof coating film made by adding crushed tire rubber to a rubber asphalt emulsion, which can be coated in a thickness of several mm or more at a time, and which can be coated easily. The solidification of the film progresses gradually, making it less susceptible to changes in temperature, making it easy to apply and producing a film of uniform thickness, making it a low-cost product suitable for injection filling. It is intended as a self-hardening waterproofing agent.

That is, a tire pulverized rubber-containing rubber product is a mixture of (A) a rubber asphalt emulsion and (B) pulverized tire rubber that has been impregnated with an aqueous solution of an emulsion slowing agent and, if necessary, a spreading agent added thereto and dried. Hard rubber asphalt waterproof material. It exists in

The rubber asphalt emulsion (A) used in this invention is a mixture of anionic asphalt emulsion (solid content 45 to 72% by weight) and synthetic rubber latex (solid content
A mixture of 3 to 30% by weight of 45 to 60% by weight) is suitable. Anionic asphalt emulsions emulsify asphalt more easily than other cationic, nonionic, and amphoteric asphalt emulsions.
It can be emulsified with a small amount of anionic emulsifier. Therefore, it is particularly preferable because it is easy to separate asphalt from water by coagulating it with the slow coagulating agent, and the separated asphalt has good properties.However, other emulsions may also be used with a coagulant as appropriate. It can be used in a similar manner depending on the selection.

Synthetic rubber latexes include styrene-butadiene rubber, chloroprene rubber, butadiene rubber,
Latexes of isoprene rubber and acrylonitrile butadiene rubber are preferred because they have good compatibility with asphalt and have a remarkable effect of improving the stretchability, toughness, heat resistance, weather resistance, and waterproofness of asphalt.

If the rubber latex is less than 3%, the effect will be less and 30%.
Above this, storage stability and workability are poor, and costs are high. Preferably 10 to 20% by weight of rubber latex based on the asphalt emulsion is optimal for this purpose.

Crushed tire rubber is crushed pieces obtained by crushing and crushing old tires with high elasticity using a powerful crusher. When viewed under magnification, the rubber has an uneven surface with ridges and a very large surface area. The present invention is characterized in that the crushed tire rubber is impregnated with and adhered to a slow coagulating agent.

That is, a tire in which the slow coagulant is impregnated into the concave portions of the crushed rubber and adhered to the entire surface by scattering, spraying, or dipping the crushed rubber with an aqueous solution of the slow coagulant at a desired concentration. Crushed rubber (B) is obtained. When the rubber asphalt emulsion (A) and the above-mentioned crushed tire rubber (B) are mixed during use, the slow coagulating agent gradually dissolves from the surface coating part of the crushed rubber to the impregnated concave part, and gradually solidifies the emulsion. It becomes possible to eliminate the disadvantages of rapid solidification such as in the case of forming a uniform coating film during operation.

The blending amount of the crushed rubber (B) is in the range of 50 to 300 parts by weight per 100 parts by weight of the rubber asphalt emulsion (A), and the amount of the crushed rubber (B) is in the range of 50 to 300 parts by weight, depending on the purpose of use of the waterproofing material, thickness, elasticity, cushioning performance, cost, etc. It can be determined as appropriate.
As the slow coagulant, sodium silifluoride and potassium silifluoride are particularly preferred; for example, when these are used, 0.5
~10% by weight is used as an aqueous solution. This amount is determined depending on the conditions at the construction site, such as the degree of self-hardening of the intended self-hardening rubber asphalt waterproofing material and the speed and speed of coagulation. Usually about 2 to 6% is optimal.

As mentioned above, the spreading agent is a water-soluble polymer with paste-like properties that acts to spread the coagulant uniformly on the recesses and surface of the crushed rubber, and it adheres well to the water-repellent surface unique to the crushed rubber. , which is preferable because it allows impregnation.
In particular, since crushed rubber is obtained by crushing old tires using a crusher, it is often contaminated with oil and the like, which prevents uniform impregnation and adhesion of the aqueous coagulant solution, so the addition of a spreading agent is particularly preferred in such cases. In addition, this spreading agent prevents the coagulant attached to the crushed rubber from drying and falling off during storage and transportation, and prevents the coagulant from being unevenly distributed and the self-hardening properties of the waterproofing material becoming uneven. Add and use.

Since the present invention has such a structure, a coated waterproof layer or a filled waterproof layer with excellent elasticity and cushioning properties can be obtained by mixing rubber asphalt emulsion with crushed tire rubber.

Utilizing the characteristics of crushed tire rubber, it is impregnated with a slow coagulating agent and, if necessary, a spreading agent, and then adhered to it.
Since it is mixed with the rubber asphalt emulsion and made to self-harden and coagulate, coagulation progresses gradually and uniformly, resulting in a coated layer or filled layer with uniform thickness and properties.

Since it sets uniformly no matter what thickness it is applied at once, it is easy to work, saves labor, and can be applied with high efficiency, and a low-cost waterproofing material can be obtained using a large amount of crushed old tire rubber.

Example 1 (A) Rubber asphalt emulsion prepared by mixing 10 parts by weight of anionic SBR latex with 90 parts by weight of an asphalt emulsion emulsified with an anionic surfactant. (B) An aqueous solution of 4 parts by weight of sodium silicofluoride was sprayed. A self-hardening waterproofing material made by mixing and preparing 100 parts by weight of crushed old tire rubber (particle size: 10-50 mesh) (A) and (B), which had been uniformly impregnated and adhered with water, was applied on a concrete plate to a thickness of 5 mm. (room temperature 25℃)
Coagulation starts 10 minutes after preparation and ends 3 hours later.
A rubber asphalt waterproof coating with uniform elasticity was obtained throughout the interior.

The application work was easy.

Example 2 (A) Rubber asphalt emulsion prepared by mixing 80 parts by weight of asphalt emulsion emulsified with an anionic surfactant and 20 parts by weight of nonionic chloroprene rubber latex (B) 7 parts by weight of potassium silicofluoride, 1 part by weight of calcium caseinate A self-hardening waterproofing material prepared by mixing 200 parts by weight of crushed old tire rubber (particle size: 10 to 50 mesh) (A) and (B), which was dried by spraying 10 parts by weight of an aqueous solution to uniformly impregnate and adhere,
When the mixture was injected and filled between two slate wall plates spaced apart by mm, setting started 5 minutes after preparation (room temperature 10°C) and finished 1 hour later. The filled intermediate waterproof layer coagulated uniformly without any lumps, and a low-cost waterproof layer containing a large amount of crushed old tire rubber was obtained, which was rich in elasticity and cushioning properties.

Claims (1)

[Scope of Claims] 1 (A) Rubber asphalt emulsion (B) Crushed tire rubber impregnated with an aqueous solution of an emulsion slow coagulant and a spreading agent added if necessary, and dried. The above (A) and (B) are mixed. A self-hardening rubber asphalt waterproofing material containing tire crushed rubber. 2. Self-hardening rubber containing crushed tire rubber according to claim 1, characterized in that 50 to 300 parts by weight of crushed tire rubber (B) is mixed with 00 parts by weight of the rubber asphalt emulsion (A). Asphalt waterproof material. 3 Rubber asphalt emulsion (A) is an anionic asphalt emulsion (solid content 45-72% by weight)
Synthetic rubber latex (solid content 45-60% by weight)
The self-hardening rubber asphalt waterproofing material containing crushed tire rubber according to claim 1, which is a mixture of 3 to 30% by weight of: