JP2003138508A - Method of manufacturing elastic pavement material and elastic pavement material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing elastic pavement material capable of providing a sufficient strength in a short time while providing a proper usable time, having little blistering due to foaming, and providing the elastic pavement material with high final strength. SOLUTION: This method of manufacturing the elastic pavement material comprises the steps of mixing aggregate and aromatic amine compounds beforehand and forming the elastic pavement material by mixing urethane prepolymer therewith.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to an elastic pavement material, and in particular, an elastic pavement having a high strength which can obtain an appropriate pot life, can obtain high strength in a short time, and has almost no blistering due to foaming. The present invention relates to a method for manufacturing a material.

[0002]

Conventionally, an elastic body obtained by curing a mixture of pulverized material (aggregate) such as waste rubber or plastic and urethane prepolymer (binder) has been used as a paving material for roads. Known elastic paving materials are known. Since this kind of elastic pavement material is used as a pavement material for roads and sidewalks, it is required to have high strength, and it is also possible to drive an automobile etc. in a short time (for example, 2 to 4 hours) after molding and construction. So that you can walk
It is also desired to provide sufficient strength in a short time after molding. In order to meet this demand, when manufacturing such an elastic pavement material, a curing agent or a catalyst that accelerates the curing of the urethane prepolymer is used, and the manufacturing method includes a urethane prepolymer and a curing agent. Mix
Then, a method of mixing the aggregate and molding, or a method of mixing the aggregate and the catalyst and then mixing the urethane prepolymer and molding is adopted.

By the way, in the method of mixing the urethane prepolymer and the curing agent, and then mixing and molding the aggregate,
Since the curing begins when the urethane prepolymer and the curing agent are mixed, the urethane prepolymer has already been cured when the aggregate is put into the mold, and the moldable time (working time) is short. There was a problem of becoming. Also, since it is difficult to obtain a uniform mixture from the urethane prepolymer that has been hardened and the aggregate, it is not possible to obtain sufficient strength in a short time after molding, or the final strength of the obtained elastic pavement material. There is a case where the above demands are not satisfied due to a shortage.

Further, in the method of mixing the aggregate and the catalyst, and then mixing the urethane prepolymer and molding, the polyurethane foams by the carbon dioxide gas generated during the curing of the urethane prepolymer, and the resulting elastic pavement material is obtained. There was a problem of blistering. In addition, it may take a long time for the molded elastic pavement material to have sufficient strength to withstand use, and there have been cases in which the above demands are not satisfied.

The present invention has been made in view of the above problems, and an object thereof is to obtain an adequate pot life and to obtain sufficient strength in a short time, and to prevent blistering due to foaming. It is an object of the present invention to provide a method for manufacturing an elastic pavement material that can obtain an elastic pavement material having high strength.

[0006]

Means for Solving the Problems As a result of intensive studies by the present inventors in order to achieve the above object, a mixture of a preliminarily prepared aggregate and a curing agent is mixed with a urethane prepolymer, molded and used. It has been found that by specifying an aromatic amine compound as the curing agent, all the problems in the conventional method can be solved, and the present invention has been completed.

That is, the present invention relates to the following elastic pavement manufacturing method and elastic pavement material. (1) A method for producing an elastic paving material, which comprises mixing an aggregate and an aromatic amine compound in advance, and then mixing and molding a urethane prepolymer. (2) The method for producing an elastic paving material according to (1), wherein the urethane prepolymer is an aromatic urethane prepolymer. (3) The method for producing an elastic paving material according to (1) or (2), wherein a catalyst and / or a polyol is further mixed with the aggregate before mixing the urethane prepolymer. (4) An elastic pavement material which is obtained by previously mixing an aggregate and an aromatic amine compound, mixing the mixture with a urethane prepolymer, molding the mixture, and curing the mixture.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, first, an aromatic amine compound and an aggregate are mixed to form a mixture. Next, a urethane prepolymer is mixed with the mixture, molded, and cured to obtain an elastic pavement material. According to the present invention, until the aggregate and the urethane prepolymer are mixed, the urethane prepolymer and the aromatic amine compound as the curing agent do not come into contact with each other. By mixing the above, the start of the reaction can be delayed as compared with the case where the mixture of the urethane prepolymer and the aromatic amine compound is mixed with the aggregate. At the same time, unlike the aliphatic amine compound, the aromatic amine compound used does not cause the curing reaction to proceed at once in a short time, so that an appropriate pot life for molding can be taken.

On the other hand, since the aromatic amine compound and the aggregate are mixed in advance, a uniform mixture can be easily obtained,
Since the urethane prepolymer that has not been cured is mixed with this, the aromatic amine compound, the aggregate and the urethane prepolymer can be sufficiently mixed, and the curing of the urethane prepolymer can proceed substantially uniformly throughout the elastic pavement material. In addition, since the aromatic amine compound can increase the strength when cured as compared with the aliphatic amine compound, compared to the case of using only the catalyst or the case of using the aliphatic amine compound, after molding It is possible to produce an elastic pavement material which can obtain sufficient strength in a short time and also has high final strength. Further, since the urethane prepolymer is cured by the aromatic amine compound, the amount of the catalyst used can be reduced or eliminated, and the blistering due to foaming can be reduced.

The aromatic amine compound used in the present invention is preferably a diamine compound, and the aromatic ring in the compound is preferably a benzene ring or a naphthalene ring. Specifically, for example, 4,4'-diaminodiphenyl, 4,4'-diaminodiphenyl ether, 2,3-
Diaminotoluene, 3,4-diaminotoluene, 2,4
-Diaminotoluene, 2,6-diaminotoluene, 2,
4-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 1,3-phenylenediamine, 1,4
-Phenylenediamine, 3,5-dimethylthio-2,4
-Toluenediamine, 3,5-dimethylthio-2,6-
Toluenediamine, naphthylene-1,5-diamine, liquid polymer of polyphenyl polymethylene polyamine of the type obtained by formaldehyde condensation of aniline, 1,3-dimethyl-2,4-diaminobenzene,
1,3-diethyl-2,4-diaminobenzene, 1,3
-Dimethyl-2,5-diaminobenzene, 1,4-diisopropyl-2,5-diaminobenzene, 2,4-diaminomesitylene, 1,3,5-triethyl-2,4-diaminobenzene, 1,3,5 -Triethyl-2,6-diaminobenzene, 1,3,5-triisopropyl-2,
4-diaminobenzene, 1-methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl-3,5-diethyl-2,6-diaminobenzene; 2,3-dimethyl-1,4-diamino Naphthalene, 2,6-dimethyl-
1,5-diaminonaphthalene, 2,6-diisopropyl-1,5-diaminonaphthalene, 2,6-dibutyl-
1,5-diaminonaphthalene; 3,3 ', 5,5'-tetraisopropylbenzidine;3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane,
3,3 ', 5,5'-tetraethyl-4,4'-diaminodiphenylmethane, 3,3', 5,5'-tetraisopropyl-4,4'-diaminodiphenylmethane,
3,3 ', 5,5'-Tetrabutyl-4,4'-diaminodiphenylmethane, 3,5-diethyl-3'-methyl-2', 4-diaminodiphenylmethane, 3,5-diisopropyl-3'-methyl- 2 ', 4-diaminodiphenylmethane, 3,3'-diethyl-2,2'-diaminodiphenylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane;3,3',5,5'-tetraethyl-4,4'-diaminodiphenyl ether, 3,
3'5,5'-tetraisopropyl-4,4'-diaminodiphenyl ether; 3,3'-dichloro-4,4 '
-Diaminodiphenylmethane; tert-butyltoluenediamine; 1,3,5-triisopropyl-2,4-
Diaminobenzene; 4,4'-bis (sec-butylamino) diphenylmethane; 1,4- (sec-butylamino) benzene and the like.

These aromatic amine compounds can be used alone or as a mixture. As a mixture,
For example, a mixture of 2,3-diaminotoluene and 3,4-diaminotoluene, 2,4-diaminotoluene and 2,
A mixture with 6-diaminotoluene [including a mixture of 80:20 (weight ratio)], a mixture of 2,4-diaminodiphenylmethane and 4,4′-diaminodiphenylmethane, 1,3-phenylenediamine and 1,4- Mixture with phenylenediamine, 3,5-dimethylthio-2,4-
Mixture of toluenediamine and 3,5-dimethylthio-2,6-toluenediamine, 1-methyl-3,5-diethyl-2,4-diaminobenzene and 1-methyl-3,5
-Diethyl-2,6-diaminobenzene, a polyamine mixture in which 2-chloroaniline and aniline are condensed with formaldehyde in the presence of a mineral acid, and the like.

Among them, 3,5-dimethylthio-2,4-toluenediamine and 3,5-dimethylthio-diamine are preferable because they are liquid at room temperature and are easy to handle, and the obtained elastic reinforcing material exhibits high strength. Mixture with 2,6-toluenediamine, 1-methyl-3,5-diethyl-
Preference is given to mixtures containing 2,4-diaminobenzene and 1-methyl-3,5-diethyl-2,6-diaminobenzene in different proportions.

Examples of aggregates used in the present invention include waste rubber such as tire scraps, recycled rubber, rubber chips (crushed products) such as waste polyurethane elastomers, crushed natural stones, wood chips, and plastic chips. To be
As the rubber chip, for example, natural rubber, neoprene rubber, chloroprene rubber, nitrile rubber, acrylic rubber,
Examples include chips of butyl rubber, styrene butadiene rubber, ethylene / propylene / diene terpolymer rubber, and the like.

The urethane prepolymer used in the present invention is a reaction product of an organic polyisocyanate and a polyol and has an isocyanate group at the molecular end.

As the organic polyisocyanate, for example,
Tolylene diisocyanate (TDI), diphenylmethane diisocyanate (4,4'-diphenylmethane diisocyanate (MDI), mixture of 4,4'-diphenylmethane diisocyanate and 2,4-diphenylmethane diisocyanate), xylylene diisocyanate (XDI), naphthalene diisocyanate ( Aromatic polyisocyanates such as NDI), aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI), alicyclic polyisocyanates such as isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate, norbornane diisocyanate (NBDI), carbodiimides of the above polyisocyanates Modified polyisocyanate, isocyanurate modified polyisocyanate,
Examples include burette modified polyisocyanate. These polyisocyanates can be used alone or as a mixture.

As the polyol, polyhydric alcohols, polyester type polyols, polyether type polyols,
Other polyols, mixtures thereof, and the like can be used.

Examples of the polyhydric alcohols include glycols such as ethylene glycol, propylene glycol, butylene glycol, hexamethylene glycol and diethylene glycol, trifunctional polyols such as glycerin, trimethylolpropane and triethanolamine, diglycerin and pentaerythritol. And 4 functional polyols, 6-functional polyols such as sorbitol, 8-functional polyols such as sugar, and the like.

Examples of the polyester polyols include polyethylene adipate and polycaprolactone polyol.

Examples of the polyether polyol include addition polymers of the above-mentioned polyhydric alcohols and alkylene oxides such as ethylene oxide and propylene oxide.

Other usable polyols include acrylic polyols, polybutadiene polyols, higher fatty acid esters containing hydroxy groups such as castor oil, polyether polyols or polyester polyols, polyols obtained by grafting vinyl monomers, and polytetramethylene ether glycols. .

The organic polyisocyanate and the polyol are reacted in excess of polyisocyanate. The NCO content in the obtained prepolymer is 2% by weight or more and 20% by weight.
The following is preferable. When the NCO content is 2% by weight or more, it has a sufficient binding force to the aggregate, and when the NCO content is 20% by weight or less, the obtained elastic pavement material exhibits high strength. More preferably, it is 5% by weight or more and 15% by weight or less.

Although the molecular weight of the prepolymer is not particularly limited, it is preferably 300 or more (weight average molecular weight) from the viewpoint of strength of the elastic pavement material, and 3000 or less from the viewpoint of fluidity and handleability of the prepolymer.

In the method of the present invention, a polyol compound and / or a curing catalyst may be used together with the aromatic amine compound. By using these, the curing rate can be increased as compared with the case where only the aromatic amine compound is used. Examples of usable polyol compounds include glycols (polytetramethylene ether glycol, polypropylene glycol, etc.), trivalent alcohols (glycerin, etc.), polyhydric alcohols (pentaerythritol, sorbitol, etc.), amine polyols, polymer polyols (alkylstyrene. (Polyether polyol, acrylonitrile / polyether polyol, etc.), polybutadiene polyol, polyether polyol, polyester polyol, castor oil and the like. Examples of the curing catalyst include tin compounds such as dibutyltin dilaurate, dioctyltin dilaurate and dioctyltin dineodecanate, lead compounds such as lead octylate, and 2,2′-
Examples thereof include amine-based catalysts such as dimorpholino diethyl ether.

The mixing ratio of the aggregate and the urethane prepolymer is not particularly limited, but the range is the aggregate / urethane prepolymer (weight ratio), preferably 95/5 to 60/4.
0, more preferably 85/15 to 75/25.
The mixing ratio of aggregate and urethane prepolymer is 95/5 to 60
When it is / 40, a high-strength elastic pavement material without blistering and foaming can be obtained.

The amount of the aromatic amine compound mixed is not particularly limited, but the ratio of the number of amino groups of the aromatic amine compound to the number of isocyanate groups of the urethane prepolymer is preferably 0.05 to 0.8. Within this range, an appropriate pot life can be obtained and an elastic pavement material with high strength can be obtained.

The mixture of the polyol compounds is not particularly limited, but the ratio of the number of hydroxyl groups of the polyol compound to the number of isocyanate groups of the urethane prepolymer is preferably 0.01 to 0.8. Within this range, an appropriate pot life can be obtained and an elastic pavement material with high strength can be obtained. The amount of the catalyst used varies depending on the type of catalyst and the type of urethane prepolymer, but is 0.05 to 7% by weight based on the urethane prepolymer.

If desired, the elastic pavement material of the present invention may contain a plasticizer, a toner, a pigment, a filler, a light stabilizer, an ultraviolet absorber, an antioxidant and the like.

The method for producing an elastic pavement material according to the present invention is a prefabricated method in which an interlocking material or the like is made in a factory using a formwork and is laid at a construction site, and an aggregate and an aromatic amine compound are prepared at the construction site. After mixing, there is a field construction method for manufacturing an elastic paving material by mixing and molding a polyurethane urea polymer, and curing, and the present invention can be applied by any method, but it is preferably used for the field construction method. To be

The method for mixing the aromatic amine compound and the aggregate is not particularly limited, and any commonly used method may be used. The mixing of the mixture with the urethane prepolymer may be carried out by a known method, but it is particularly preferable to use a screw type mixer. For example, at the construction site, the aggregate is stirred in a mixing stirrer such as a mortar mixer together with a predetermined amount of an aromatic amine compound and, if necessary, other curing agents and catalysts to form a uniform mixture, and the urethane prepolymer is added to the mixture. Add and mix evenly. The obtained mixture is sprayed to a construction site in a predetermined thickness, rolled by a heat roller (temperature: 40 to 100 ° C.), etc., and then left standing to cure to obtain an elastic paving material. In addition to this, when manufacturing an aggregate, an aromatic amine compound and, if necessary, a curing agent and a catalyst are mixed, and then mixed with a urethane prepolymer in a screw type mixer on site to form an elastic paving material. You may get it.

According to the manufacturing method of the present invention, the pot life of the elastic paving material can be adjusted to 10 to 30 minutes. In addition, the strength of the elastic pavement material 2 hours after the completion of the rolling compaction is 7 to 10 k.
The final strength can be 8 to 12 kgf / cm ^{2 in} gf / cm ² .

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Pot life Time in the environment of 20 RH 90 RH% 1 atm until the aggregate moves by touching with a spatula after completion of rolling.

The surface of the test piece (12 cm × 12 cm, thickness 1 cm) after being left for 16 hours in an environment of swelling 20 ° C., 90 RH% and 1 atm, is visually observed.

Strength after 2 hours (kgf / cm ² ) Tensile strength (kgf / cm ² ) of a test piece (12 cm × 12 cm, thickness 1 cm) after being left for 2 hours in an environment of 20 ° C., 90 RH% and 1 atm Is measured at a tensile speed of 100 mm / min using a universal material testing machine (manufactured by Instron).

Final strength (kgf / cm ² ) The tensile strength (kgf / cm ² ) of the test piece (12 cm × 12 cm, thickness 1 cm) after standing for 24 hours in an environment of 40 ° C. and 50 RH% was measured after 2 hours. It is measured in the same manner as the strength of.

Example 1 100 parts by weight of rubber chips were mixed with 80:20 (weight of 3,5-dimethylthio-2,4-toluenediamine and 3,5-dimethylthio-2,6-toluenediamine, which are aromatic amine compounds). Ratio) 3.0 parts by weight of a mixture (Etacure 300), 0.3 parts by weight of dibutyltin dilaurate and polypropylene glycol (molecular weight 2000,
2.7 parts by weight of OH value = 56) were mixed to obtain a uniform mixture. Immediately, 25 parts by weight of an MDI-based urethane prepolymer (weight average molecular weight = 1000, NCO content = 9% by weight) was mixed with the mixture, and the resulting mixture was molded and rolled using a heat roller to obtain an elastic paving material. Got The time from the mixing of the rubber chip and the aromatic amine compound to the end of the compaction was 3 minutes. About the obtained elastic pavement material, pot life (min), blistering, strength after 2 hours (kgf / cm
² ) and the final strength (kgf / cm ² ) were measured. The results are shown in Table 1.

Example 2 In the same manner as in Example 1 except that an HDI urethane prepolymer (weight average molecular weight = 1000, NCO content = 9% by weight) was used as the urethane prepolymer instead of the MDI urethane prepolymer. An elastic pavement material was obtained. About the obtained elastic pavement material, pot life (minutes), blistering, 2
Strength after time (kgf / cm ² ) and final strength (kg
f / cm ² ) was measured. The results are shown in Table 1.

Comparative Example 1 An elastic pavement material was obtained in the same manner as in Example 1 except that the aromatic amine compound was not used. About the obtained elastic pavement material, pot life (minutes), swelling, strength after 2 hours (k
gf / cm ² ) and final strength (kgf / cm ² ) were measured. The results are shown in Table 1.

Comparative Example 2 MDI urethane prepolymer (weight average molecular weight = 10)
00, NCO content = 9% by weight), 25 parts by weight of aromatic amine compound (Etacure 300) and 0.3 parts by weight of dibutyltin dilaurate are mixed, and immediately thereafter, 100 parts by weight of rubber chips are mixed. The obtained mixture was compressed in the same manner as in Example 1 to obtain an elastic pavement material. The time from the mixing of the urethane prepolymer and the aromatic amine to the end of the compaction was 6 minutes. The obtained elastic pavement material was measured for pot life (minutes), blistering, strength after 2 hours (kgf / cm ² ) and final strength (kgf / cm ² ). The results are shown in Table 1.

Comparative Example 3 An elastic pavement material was obtained in the same manner as in Example 1 except that 2.0 parts by weight of hexamethylenediamine was used instead of 3.0 parts by weight of the aromatic amine compound (Etacure 300). It was The obtained elastic pavement material was measured for pot life (seconds), blistering, strength (kgf / cm ² ) after 2 hours and final strength (kgf / cm ² ). The results are shown in Table 1.

[0041]

[Table 1]

From the results shown in Table 1, when the catalyst was mixed in the rubber chips and the aromatic amine compound was not used, carbon dioxide gas was generated during the curing of the urethane prepolymer, and the surface of the obtained elastic pavement was swollen. Occurred (Comparative Example 1). When an aliphatic amine compound was used as the amine compound, curing rapidly occurred, the obtained elastic pavement material had low strength, and the pot life was hardly obtained (Comparative Example 3). Furthermore, when the urethane prepolymer was mixed with the curing agent and then the rubber chips were mixed and molded, sufficient pot life was not obtained, and the strength of the elastic pavement material was low 2 hours after the completion of the compaction (comparison). Example 2). On the other hand, according to the methods of Examples 1 and 2, it is possible to take a sufficient pot life for performing the construction work, and it is possible to obtain an elastic pavement material having high strength in a short time, There was no blistering. When an aromatic urethane prepolymer was used as the urethane prepolymer, particularly high strength could be obtained (Example 1).

[0043]

As described above, according to the method of the present invention, an adequate pot life can be obtained, while sufficient strength can be obtained in a short time, there is almost no blistering due to foaming, and the final strength is also high. An elastic paving material can be obtained.

Claims (4)

[Claims] 1. A method for producing an elastic pavement material, which comprises mixing an aggregate and an aromatic amine compound in advance and then mixing and molding a urethane prepolymer. 2. The method for producing an elastic paving material according to claim 1, wherein the urethane prepolymer is an aromatic urethane prepolymer. 3. The method for producing an elastic pavement material according to claim 1, wherein a catalyst and / or a polyol is further mixed with the aggregate before mixing the urethane prepolymer. 4. An elastic pavement material prepared by previously mixing an aggregate and an aromatic amine compound, mixing the mixture with a urethane prepolymer, molding the mixture, and curing the mixture.