JPH02137755A - Road-repairing material - Google Patents

Abstract

PURPOSE:To enable the road-repairing material to be improve its durability and conduct the road repairing operation in winter even while the road is wet by using cement, an aqueous emulsion of ethylene-acrylic acid ester-vinyl acetate and calcium aluminate as major components. CONSTITUTION:(A) Cement (various kinds of Portland cement, a mixed cement thereof with blast-furnace slag, (B) an aqueous emulsion of ethylene (10 to 30wt.%)-acrylic ester (40 to 85wt.%)-vinyl acetate (5 to 45wt.%) (glass transition point: higher than -30 deg.C) and (C) calcium aluminate (preferably glassy with a CaO content: 30 to 60wt.%, preferably 38 to 52wt.%) are used, as major components, at 2 to 30 pts.wt., preferably 5 to 20 pts.wt. of component D (based on solid part) and 2 to 50 pts.wt. of component C per 100 pts.wt. of component A.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to road repair materials.

[Conventional technology and its issues]

As the number of cars increases, roads in the Hokuriku and Tohoku regions are damaged by spiked tires, especially in the winter, and need to be repaired. For this repair, methods have been proposed in which the damaged area is filled with materials made of aggregates tested with cement, sand, and asphalt, or asphalt chips (for example, Japanese Patent Laid-Open Publication No. 70621/1983). However, the performance is not sufficient and the durability is insufficient for roads with heavy traffic, so there has been a desire to develop a material with good durability.

The present inventors conducted research on molds to solve the current problems related to road repair materials, and as a result, they obtained the knowledge that road repair materials with good durability can be obtained by using specific materials. The invention was completed.

[Ninth means to solve the problem]

That is, in the present invention, 100 parts by weight of cement and ethylene-
Road repair whose main components are 2 to 30 parts by weight of an aqueous copolymer emulsion consisting of acrylic acid ester and vinyl acetate with a glass transition temperature of 130°C or lower, calculated as solid content, and 2 to 50 parts by weight of calcium aluminates. It is a material.

The present invention will be explained in detail below.

As the cement used in the present invention, there are normally used portland cements such as early-early-strength and ultra-early-strength cements, and mixed cements in which these are mixed with blast furnace slag, plyacyu, chestnut, etc.

The glass transition temperature (hereinafter referred to as Tg) of the aqueous copolymer emulsion of the present invention (hereinafter referred to as the present process emulsion) is -3
The temperature is below 0°C.

− is the temperature at which various properties of the amorphous polymer suddenly change;
Below this temperature, the motion of the molecular segments of the amorphous portion of the polymer is frozen. As a method for measuring Tg, a thermal analysis method such as a DSC method is generally used.

When the T of this emulsion is -60°C or less, it means that the Tg of the copolymer constituting this emulsion is -30°C or less, and the Tg! t-
You can ask for it. However, in practice, the Tg of a homopolymer is already known (for example, in the Chemical Handbook published by Maruzen Co., Ltd.), and the Tg of a copolymer is calculated from the Tg of a homopolymer made of individual monomers as follows. It is also possible to estimate using the calculation formula.

T T T Tgng
gl g2W1: component 10 weight fraction.

W2; Component 2 #W: Component n # (Here, W1+W2+-...-+wn=1)Tg□
: T of component 1 homopolymer (Top) Tg2 = component 2 〃 Tgn: component nI Tg: T of copolymer consisting of component 1.2...n
g (K) If the Tg of this emulsion is higher than 160°C, it will not exhibit sufficient flexibility as a road repair material (hereinafter referred to as repair material), and will not be able to follow the movement of the base material, causing cracks. Otherwise, it may cause cracks.

The ethylene content in this emulsion is 10 to 30% by weight
is preferred. If the ethylene content is less than 10% by weight, the emulsion will lack alkali resistance, and if it exceeds 30% by weight, the emulsion will become unstable and may pose a problem in actual use.

Moreover, the content of acrylic ester (hereinafter referred to as ester) in this emulsion is preferably 40 to 85% by weight. If the ester content is less than 40% by weight, it is difficult to reduce the Tgt of the emulsion to -30°C or less, and the
5 Weight section? If the temperature is exceeded, emulsion polymerization may become unstable.

The ester used in the present invention is a homopolymer of T
is -50°C or less, and the isomers include normal zolobyl acrylate (n-FA), normal butyl acrylate (n-BA), hemosil acrylate (HA), and 2-methoxyethyl acrylate (c- 1
) and 2-ethylhexyl acrylate) (2EHA
) etc. can be generally used.

Vinyl acetate (hereinafter referred to as vinyl acetate) used in the present invention is not particularly limited.

The vinyl acetate content in this emulsion is preferably 5 to 45% by weight. If it is less than 5iit, the good miscibility with cement, which is one of the characteristics of the ethylene-vinyl acetate copolymer emulsion, will be lost, and if it exceeds 45% by weight, the Tgt of the emulsion will drop to -30℃ or less. becomes difficult to do.

There are no particular restrictions on the manufacturing method of this emulsion.
As the emulsion polymerization method, the well-known B method can be conveniently used. Furthermore, there are no restrictions on the polymerization conditions for bamboo, but generally the polymerization temperature is 20 to 80°C.

Examples of the catalyst include persulfates such as potassium persulfate, hydrogen peroxide, and organic peroxides.

In the case of a redox initiation system, a reducing substance such as formaldehyde sodium sulfocylate is further used in combination.

Emulsifiers include polyvinyl alcohol, diethylcellulose in hydrochloride, methylcellulose, and other purulent colloids;
Examples include nonionic surfactants such as polyoxyethylene condensates and polyoxyethylene polyoxycyclopylene block copolymers, and anionic surfactants such as alkylbenzene sulfo 7tlR salts and lauryl sulfate salts. It can be used conveniently or in combination.

The amount of emulsifier used is usually 2 to 10% by weight of the total monomer amount.

This emulsion may further contain known additives such as buffers, antifoaming agents, and preservatives, if necessary.

The usage value of this emulsion is 2 to 30 parts by weight in terms of solid content per 100 parts of cement.

Particularly preferred is 5 to 20 parts by weight. If it is less than 2 parts by weight, the repair material will lack flexibility, and if it exceeds 60 parts by weight, the compressive strength will be significantly reduced.

Calcium aluminates (hereinafter referred to as CAs) used in the present invention are usually calcium aluminate minerals produced at high temperatures in an electric furnace or rotary chamber. Either crystalline or vitreous materials can be used, and the presence of other components and impurities during the production process is not particularly limited.

As a crystalline calcium aluminate mineral, CaO
kc, Al2O3t”AlF3203 kFs Ca
If 804 is C8 and Hao)y'7fX,
Those indicated as CA, C5A3, (42A, and C3A, etc.), as well as crystalline substances in which other components are present in the crystal, such as c, A7CaX2, C3A5 (jlX2, C4AF
and c3A3cs.

Typical glassy calcium aluminate minerals have the same composition as crystalline minerals, but they are vitrified by rapid cooling and cannot be identified by X-rays.

From the viewpoint of reactivity, glassy ones are preferable to crystalline ones, and from the viewpoint of composition, the content of CaO in calcium aluminate is preferably 30 to 600 to 60 parts by weight, and 38 to 528 to 52 parts by weight. Particularly preferred.

In the present invention, one or more of the above CAs are used!
Can be used.

Convenient i of CA type is cement) for 10011L parts,
There are 2 to 50 departments with heavy responsibility. Amounts other than 2 to 50 fi parts are unfavorable in terms of rapid setting, workability, strength, and economy.

Additionally, in the present invention, a setting regulator, an inorganic substance such as an inorganic sulfate, an aggregate such as silica sand or natural sand, and a fibrous substance such as glass fiber or steel fiber can also be used in combination.

As the inorganic substance, inorganic sulfates are particularly preferred.

The term sulfuric acid salt refers to an alkali metal or alkaline earth metal salt. For example, anhydrous, chozu, and two types of calcium sulfate are preferred, and among these, poorly soluble or insoluble ones such as old-style anhydrite are preferred.

The amount of CAs and inorganic sulfates used is preferably 50 to 500 parts by weight, particularly preferably 100 to 300 parts by weight, per 100 parts by weight of CAs.

Is the repair material of the present invention different from each other? It may be mixed at the time of construction, or some or all of the materials other than the present emulsion may be mixed in advance.

Any known stirring device can be used for mixing.

For example, tilting mixer omnimixer V-type mixer,
Hensielmi mixer, Nauta mixer, ball mill, etc. can be used.

Also, the repair material can be easily applied using commonly used methods such as plastering, brushing, or spraying.

〔Example〕

Hereinafter, the present invention will be explained in detail by way of examples.

Example 1 Pure water, vinyl acetate, Nisdel and emulsifier were charged as shown in Table 1 into a stainless steel autoclave with an internal volume of 101 cm and equipped with an electromagnetic stirrer, and the internal temperature was raised to 70°C to give ethylene t60 to 9/cIrL2. has been introduced. 0.6 g of ammonium perborate as a catalyst? was added to start polymerization. The internal temperature was kept constant by adjusting the jacket temperature. After cooling for 10 hours, the contents were taken out and found to be a stable emulsion with few coarse particles. Table 1 shows the properties of the emulsion, including its polymer composition.

The viscosity was measured at 60°Os using a BM type rotational viscometer.
Measured at 30 rpm.

Next, as mentioned above, J! ! Cement, CA, inorganic substances, and aggregate were mixed into the emulsion in the proportions shown in Table 2 (in an atmosphere of 5°C), and the entire hardened product was prepared and the performance evaluation shown in Table 2 was performed.

(Toilet materials) Ethylene 2 commercial product AE-a Niacrylic acid ester n-13A %Mitsubishi Yukasaku-b: 12EIXA11 Air vinegar Pi: Vinyl acetate, Denka Kagaku Kogyo P'/A:
Polyvinyl alcohol, manufactured by Denki Kagaku Kogyo, trade name [B-
05J Surfactant: Product name [Emulden 931J, Kao HEC:
Hydroxyethyl cellulose, manufactured by Fuji Chemical Industry Na0Aa: Sodium acetate, reagent special grade ammonium persulfate: Ammonium persulfate, reagent special grade cement: Manufactured by Andes Cement Co., Ltd., ordinary Portland cement CA class; CaO 45% by weight, vitreous, plain specific surface area 6,500 cm2 / 11 Inorganic substance - 〇: ■ type anhydrite, plain specific surface area 6.1
0012/N#-(L: Setting regulator, manufactured by Denki Kagaku Kogyo, trade name "Cosmic, = M 1 Setter") Aggregate: Silica sand No. 7 The physical properties of the obtained hardened body were measured by the following method. However, curing and measurements were performed under conditions of 5°C and 65% RH.

(a) Handling time (HT) All materials in mixer? After mixing, put it in a 500 IJ container (beaker),
Time when it stops flowing even when laid down (time when fluidity disappears)
t was used as HT.

(+)) Compressive strength According to JI8 R5201. However, the material period is 1 hour, 6
The time was set as 1st and 28th.

(C) Bending @ return, TI8 R5201 was damaged. However, the material order was set on the 28th.

From Table 2, it can be seen that by adding an appropriate amount of CAs, the initial strength is developed quickly, and by adding a regular amount of the present emulsion, flexibility is imparted to the cured product. fruit! %1612
This is the case where CAs and the present emulsion were not added, and the strength development was slow and the flexibility of the cured product was low. Experiment 16 is
When this emulsion is not added, the flexibility of the cured product is low. Test No. 14 is a case where an excessive amount of emulsion is added, and the strength of the cured product is greatly reduced. Experiment/161
No. 6 is a case in which CAs are added in excess, and the flexibility of the cured product decreases.

Example 2 At Denki Kagaku Kogyo Co., Ltd.'s Aomi factory in Aomi-cho, Nishikukugi-gun, Niigata Prefecture, the repair material distributed in Experiment 42 of Example 1 and commercially available asphalt pitch (manufactured by Nippon Road) were mixed into 20 cm diameter
Fill the damaged part of the road to a depth of 10cm (at the end of December, the temperature at the time of construction was 5°C). The road was opened 3 hours after the completion of construction, but no abnormalities such as peeling were reported in the repair material toilet area even after 4 months had passed, and asphalt) f Sochi toilet area was filled with 1/2 of the filling amount after 2 weeks. was dissipating.

〔Effect of the invention〕

The repair material of the present invention has the following effects.

(1) Since a hydraulic substance is used, construction can be performed even when the base is wet.

(2) It cures within 120 minutes even at low temperatures, making it suitable for road repair work in winter.

(3) Since a polymer with a low Tg (-30°C or lower) is used, the repair material has flexibility and can follow the movement of the underlying material.

Claims (1)

[Claims] (1) 100 parts by weight of cement, composed of ethylene-acrylic ester-vinyl acetate, with a glass transition temperature of -30°C
The following aqueous copolymer emulsion is converted to solid content by 2
A road repair material whose main components are ~60 parts by weight and 2 to 50 parts by weight of calcium aluminates.