Anti-stripping agent

Abstract

To provide an anti-stripping agent with an excellent anti-stripping effect on asphalt.SOLUTION: A present invention provides an anti-stripping agent comprising a monomeric (co)polymer or a salt (A) thereof containing one or more monomers (I) selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 2-hydroxybutyl methacrylate, and uses thereof.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an anti-stripping agent. [Background technology]

[0002] Asphalt is widely used for paving the ground surfaces of roads and the like, and is heated and mixed with aggregate during construction. Asphalt is non-polar and hydrophobic, while aggregate is hydrophilic, the adhesion between the two is sometimes insufficient, and there is a risk of the two peeling off when they come into contact with water, such as rainfall or groundwater.

[0003] The development of technologies to prevent such peeling is underway. For example, Patent Document 1 describes that a heated asphalt additive containing an acidic organic phosphoric acid compound and an amine compound suppresses the destruction of the adhesive interface between aggregate and bituminous material and has an excellent peeling prevention effect. Patent Document 2 describes that an asphalt modifier made of a specified polyester resin can quickly develop water resistance, and peeling of the asphalt coating due to the intrusion and retention of water is unlikely to occur even if the asphalt pavement surface is exposed to rainwater or the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3905379 [Patent Document 2] JP 2022-93064 A Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, the importance of preventing asphalt peeling has increased from the viewpoint of road maintenance and management. Accordingly, an object of the present invention is to provide an anti-peeling agent having excellent asphalt peeling prevention effect. [Means for solving the problem]

[0006] The present invention provides the following [1] to

[16] . [1] An anti-stripping agent comprising a (co)polymer of a monomer containing one or more monomers (I) selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, and 2-hydroxybutyl methacrylate, or a salt thereof (A). [2] The (co)polymer or its salt (A) is a copolymer of a monomer (I) and a copolymerizable monomer (II) or its salt, The monomer (II) is Monomer (II-1) represented by the following general formula (1), and / or Monomer (II-2) represented by the following general formula (2): The anti-stripping agent according to [1], R 1 -O-(A 1 O) n1 -R 2 (1) (In the formula, R 1 represents an alkenyl group having 2 to 5 carbon atoms. 1 O is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. n1 is the average number of moles of the oxyalkylene group added and represents a number of 1 to 200. R 2 represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. [ka] (In the formula, R 3 , R 4 and R 5 each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; m represents a number from 0 to 2. 2 O is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. n2 is the average number of moles of oxyalkylene groups added and represents a number from 1 to 200. X represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. [3] Monomer (II) is The anti-stripping agent according to [2], further comprising a monomer (II-3) copolymerizable with the monomers (II-1) and (II-2). [4] The anti-stripping agent according to [3], wherein the monomer (II-3) contains a monomer represented by the following general formula (3): [ka] (In the formula, R 6 ~R 8 are each independently a hydrogen atom, a methyl group, or -(CH2) p COOM 2 group, provided that -(CH2) p COOM 2 When representing a group, -COOM 1 Group or other -(CH2) p COOM 2 The M group may form an anhydride group. 1 and M 2 each independently represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, or a substituted alkylammonium group. p represents an integer of 0 to 2. [5] The anti-exfoliation agent according to any one of [1] to [4], wherein the weight ratio of the monomer (I) to 100% by weight of the monomers constituting the copolymer or its salt (A) is 1 to 97% by weight. [6] The anti-stripping agent according to any one of [2] to [5], wherein the weight ratio of the monomer (II-1) to 100% by weight of the monomers constituting the copolymer or a salt thereof (A) is 1 to 97% by weight. [7] The anti-stripping agent according to any one of [2] to [6], wherein the weight ratio of the monomer (II-2) to 100% by weight of the monomers constituting the copolymer or a salt thereof (A) is 1 to 50% by weight. [8] The anti-stripping agent according to any one of [3] to [7], wherein the weight ratio of the monomer (II-3) to 100% by weight of the monomers constituting the copolymer or a salt thereof (A) is 1 to 50% by weight. [9] The anti-stripping agent according to any one of [1] to [8], wherein the copolymer or a salt thereof (A) has a weight average molecular weight Mw of 5,000 to 100,000.

[10] The anti-stripping agent according to any one of [1] to [9], wherein the ratio Mw / Mn of the weight average molecular weight Mw to the number average molecular weight Mn of the copolymer or its salt (A) is 1.01 to 10.0.

[11] An asphalt composition comprising the antistripping agent according to any one of [1] to

[10] .

[12] The asphalt composition according to

[11] , wherein the content of the antistripping agent is 1 to 20 parts by weight per 100 parts by weight of the asphalt-based material.

[13] An asphalt emulsion composition comprising the antistripping agent according to any one of [1] to

[10] .

[14] An asphalt pavement laminate comprising a surface layer, a base layer, and a roadbed, wherein either the surface layer or the base layer is a layer comprising the asphalt composition according to

[11] or

[12] .

[15] The laminate according to

[14] , further comprising a layer containing the asphalt emulsion composition according to

[13] on the surface of the surface layer, between the surface layer and the base layer, and / or between the base layer and the roadbed.

[16] A method for producing an asphalt pavement laminate according to

[14] , comprising sequentially forming a base layer and a surface layer on the surface of a roadbed, wherein either the surface layer or the base layer is a layer containing the asphalt composition according to

[11] or

[12] . Effect of the Invention

[0007] INDUSTRIAL APPLICABILITY The present invention provides an anti-stripping agent capable of preventing separation between asphalt and aggregate, thereby improving the durability of asphalt pavement and being useful in maintaining and managing paved surfaces such as roads. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] [1. Anti-stripping agent] The anti-stripping agent contains the following (co)polymer or a salt thereof (A).

[0009] [1.1 Monomers constituting the (co)polymer or its salt (A)] The (co)polymer or its salt (A) is a homopolymer or copolymer of a monomer containing the monomer (I).

[0010] -Monomer (I)- The monomer (I) is one or more monomers selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, and 2-hydroxybutyl methacrylate. Among these, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and 4-hydroxybutyl acrylate are preferred. The monomer (I) may be one type or a combination of two or more types.

[0011] -Monomer (II)- The (co)polymer or its salt (A) may be a copolymer or its salt of the monomer (I) and another monomer. The other monomer may be a monomer (II) that is copolymerizable with the monomer (I). Examples of the monomer (II) include the following monomers (II-1), (II-2), and (II-3). The monomer (II) preferably contains at least the monomer (II-1) and / or (II-2), or at least a combination of the monomer (II-1) and / or (II-2) and the monomer (II-3).

[0012] -Monomer (II-1)- Monomer (II-1) is R 1 -O-(A 1 O) n1 -R 2 (1) It is a polyalkylene glycol monoalkenyl ether represented by the formula:

[0013] R in general formula (1) 1 R represents an alkenyl group. The number of carbon atoms in the alkenyl group is usually 2 or more, preferably 3 or more. The upper limit is preferably 5 or less. The alkenyl group may have one or more double bonds and may be either a straight chain or a branched chain. 1Examples of the alkyl group include, but are not limited to, an allyl group, a methallyl group, and a residue of 3-methyl-3-buten-1-ol, with an allyl group being preferred.

[0014] A in general formula (1) 1 O may be the same or different and represents an oxyalkylene group. The number of carbon atoms in the oxyalkylene group is usually 2 to 18, for example, 2 to 16, 2 to 14, 2 to 12, 2 to 10, or 2 to 8, preferably 2 to 6, and more preferably 2 to 4. Examples of the oxyalkylene group include an oxyethylene group (ethylene glycol unit), an oxypropylene group (propylene glycol unit), and an oxybutylene group (butylene glycol unit). Among them, an oxyethylene group and an oxypropylene group are preferred, and an oxyethylene group is more preferred.

[0015] A 1 The term "same or different" in the definition of O means that A 1 If multiple Os are included (n1 is 2 or more), each A 1 This means that O may be the same oxyalkylene group or different (two or more types) oxyalkylene groups. 1 In the case where a plurality of O's are contained, for example, there is a mixture of two or more oxyalkylene groups selected from the group consisting of oxyethylene groups (ethylene glycol), oxypropylene groups (propylene glycol) and oxybutylene groups (butylene glycol). A mixture of oxyethylene groups and oxypropylene groups or a mixture of oxyethylene groups and oxybutylene groups is preferred, and a mixture of oxyethylene groups and oxypropylene groups is more preferred. 1 In an embodiment containing a plurality of O, the addition of two or more types of oxyalkylene groups may be in a block form or a random form.

[0016] In the general formula (1), n1 is the average number of moles of oxyalkylene groups added. In this specification, the average number of moles added means the average number of moles of alkylene glycol units added to 1 mole of monomer. The lower limit of n1 is usually 1 or more, 2 or more, 3 or more, preferably 4 or more, 5 or more, 6 or more, more preferably 7 or more, 8 or more, 9 or more, and further preferably 10 or more. The upper limit is usually 200 or less, 180 or less, 150 or less, 120 or less, 100 or less, preferably 80 or less, 60 or less, 50 or less, and more preferably 40 or less. Therefore, n1 is usually 1 to 200, 2 to 180, 3 to 150, 4 to 120, 5 to 100, preferably 6 to 90, 7 to 80, 8 to 60, 9 to 50, and more preferably 10 to 40.

[0017] R in general formula (1) 2 is a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and even more preferably a hydrogen atom or a methyl group. The hydrocarbon group may be either saturated or unsaturated and may be linear, branched, or cyclic, although a saturated hydrocarbon group is preferred, and a linear saturated hydrocarbon group is more preferred.

[0018] The monomer (I) can be produced, for example, by adding 1 to 80 moles of an alkylene oxide to an unsaturated alcohol such as allyl alcohol, methallyl alcohol, or 3-methyl-3-buten-1-ol.

[0019] Examples of the monomer represented by the general formula (1) include (poly)ethylene glycol (meth)allyl ether, (poly)ethylene glycol 3-methyl-3-butenyl ether, (poly)ethylene glycol (poly)propylene glycol (meth)allyl ether, (poly)ethylene (poly)propylene glycol (meth)allyl ether, (poly)ethylene (poly)propylene glycol 3-methyl-3-butenyl ether, (poly)ethylene (poly)butylene glycol (meth)allyl ether, (poly)ethylene (poly)butylene glycol 3 -methyl-3-butenyl ether, methoxy(poly)ethylene glycol (meth)allyl ether, methoxy(poly)ethylene glycol 3-methyl-3-butenyl ether, methoxy(poly)ethylene (poly)propylene glycol (meth)allyl ether, methoxy(poly)ethylene (poly)propylene glycol 3-methyl-3-butenyl ether, methoxy(poly)ethylene (poly)butylene glycol (meth)allyl ether, methoxy(poly)ethylene (poly)butylene glycol 3-methyl-3-butenyl ether. Among these, from the viewpoint of the balance between hydrophilicity and hydrophobicity, (poly)ethylene glycol (meth)allyl ether, (poly)ethylene glycol (poly)propylene glycol (meth)allyl ether, (poly)ethylene (poly)propylene glycol (meth)allyl ether, (poly)ethylene glycol 3-methyl-3-butenyl ether, (poly)ethylene (poly)propylene glycol 3-methyl-3-butenyl ether are preferred, and (poly)ethylene glycol (meth)allyl ether is more preferred.

[0020] In this specification, "(meth)allyl" means both allyl and methallyl. "(meth)acrylate" means both acrylate and methacrylate. When (poly) is attached to the name of a compound, it means that the following substituent is singular or plural.

[0021] Examples of the method for producing the monomer represented by the general formula (1) include, but are not limited to, a method of adding an alkylene oxide to an unsaturated alcohol such as allyl alcohol, methallyl alcohol, or 3-methyl-3-buten-1-ol.

[0022] The monomer (II-1) may be one type of monomer represented by the general formula (1) alone or a combination of two or more types.

[0023] -Monomer (II-2)- The monomer (II-2) is represented by the general formula (2): [ka] It is an ester of an unsaturated carboxylic acid represented by the formula: and a (poly)alkylene glycol.

[0024] R in general formula (2) 3 , R 4 and R 5 each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

[0025] A in general formula (2) 2 O may be the same or different and represents an oxyalkylene group. The number of carbon atoms in the oxyalkylene group is usually 2 to 18, for example, 2 to 16, 2 to 14, 2 to 12, 2 to 10, or 2 to 8, preferably 2 to 6, and more preferably 2 to 4. Examples of the oxyalkylene group include an oxyethylene group (ethylene glycol unit), an oxypropylene group (propylene glycol unit), and an oxybutylene group (butylene glycol unit). Among them, an oxyethylene group and an oxypropylene group are preferred, and an oxyethylene group is more preferred.

[0026] A 2 The term "same or different" in the definition of O means that A 2 If multiple Os are included (n is 2 or more), each A 2This means that O may be the same oxyalkylene group or different (two or more types) oxyalkylene groups. 1 In the case where a plurality of O's are contained, for example, there is a mixture of two or more oxyalkylene groups selected from the group consisting of oxyethylene groups (ethylene glycol), oxypropylene groups (propylene glycol) and oxybutylene groups (butylene glycol). A mixture of oxyethylene groups and oxypropylene groups or a mixture of oxyethylene groups and oxybutylene groups is preferred, and a mixture of oxyethylene groups and oxypropylene groups is more preferred. 2 In an embodiment containing a plurality of O, the addition of two or more types of oxyalkylene groups may be in a block form or a random form.

[0027] In the general formula (2), n2 is the average number of moles of oxyalkylene groups added. The lower limit of n2 is usually 1 or more, 2 or more, 3 or more, preferably 4 or more, 5 or more, 6 or more, more preferably 7 or more, 8 or more, and further preferably 9 or more. The upper limit is usually 200 or less, 180 or less, 150 or less, 120 or less, 100 or less, preferably 80 or less, 60 or less, 50 or less, and more preferably 40 or less. Therefore, n2 is usually 1 to 200, 2 to 180, 3 to 150, 4 to 120, 5 to 100, preferably 6 to 90, 7 to 80, 8 to 60, and more preferably 9 to 40.

[0028] X in the general formula (2) is a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and even more preferably a hydrogen atom or a methyl group. The hydrocarbon group may be either saturated or unsaturated and may be linear, branched, or cyclic, but is preferably a saturated hydrocarbon group, and more preferably a linear saturated hydrocarbon group.

[0029] Examples of the monomer represented by the general formula (2) include (poly)alkylene glycol (meth)acrylates such as (poly)ethylene glycol (meth)acrylate, (poly)ethylene (poly)propylene glycol (meth)acrylate, and (poly)ethylene (poly)butylene glycol (meth)acrylate; and methoxy(poly)alkylene glycol (meth)acrylates such as methoxy(poly)ethylene glycol (meth)acrylate, methoxy(poly)ethylene (poly)propylene glycol (meth)acrylate, and methoxy(poly)ethylene (poly)butylene glycol (meth)acrylate. Among these, (poly)alkylene glycol (meth)acrylate and methoxy(poly)ethylene glycol (meth)acrylate are preferred, and methoxy(poly)ethylene glycol (meth)acrylate is more preferred.

[0030] The method for producing the monomer represented by the general formula (2) can be, for example, a method of esterifying a (poly)alkylene glycol with an unsaturated monocarboxylic acid. An example of the unsaturated carboxylic acid is (meth)acrylic acid. An example of the (poly)alkylene glycol can be (poly)ethylene glycol, (poly)ethylene (poly)propylene glycol, (poly)ethylene (poly)butylene glycol, methoxy (poly)ethylene glycol, methoxy (poly)ethylene (poly)propylene glycol, methoxy (poly)ethylene (poly)butylene glycol, and other (poly)alkylene glycols.

[0031] The monomer (II-2) may be one type of monomer represented by the general formula (2) alone or a combination of two or more types.

[0032] -Monomer (II-3)- Monomer (II-3) is a monomer that can be copolymerized with monomers (II-1) and (II-2). Monomer (II-3) is included in monomer (II), and therefore is also a monomer that can be copolymerized with monomer (I). (However, it is distinguished from monomers (I), (II-1), and (II-2).)

[0033] (Monomer represented by general formula (3)) The monomer (II-3) is represented by the general formula (3): [ka] It is a carboxylic acid derivative represented by the formula:

[0034] In general formula (3), R 6 ~R 8 are each independently a hydrogen atom, a methyl group, or -(CH2) p COOM 2 group, provided that -(CH2) p COOM 2 When representing a group, -COOM 1 Group or other -(CH2) r COOM 2 When an anhydride group is formed, the M 1 Or M 2 does not exist. 1 and M 2 each independently represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, or a substituted alkylammonium group, and p represents an integer of 0 to 2.

[0035] R 6 ~R 8 R each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. The alkyl group having 1 to 3 carbon atoms is preferably an alkyl group having 1 to 2 carbon atoms, and more preferably an alkyl group having 1 carbon atom (methyl group). 1 is preferably a hydrogen atom. 2 is a hydrogen atom, a methyl group or (CH2) p COOM 2 is preferred. 3 is preferably a hydrogen atom.

[0036] M 1 and M 2are the same or different and are a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, or a substituted alkylammonium group. 1 , M 2 are each preferably a hydrogen atom, an alkali metal, or an alkaline earth metal.

[0037] p represents an integer of 0 to 2. p is preferably 0 or 1, and more preferably 0.

[0038] Examples of the monomer represented by the general formula (3) include unsaturated monocarboxylic acid monomers and unsaturated dicarboxylic acid monomers. Examples of the unsaturated monocarboxylic acid monomers include acrylic acid, methacrylic acid, crotonic acid, and salts thereof (e.g., monovalent metal salts, ammonium salts, and organic amine salts). Examples of the unsaturated dicarboxylic acid include maleic acid, itaconic acid, citraconic acid, fumaric acid, and salts thereof (e.g., monovalent metal salts, ammonium salts, and organic amine salts), and anhydrides thereof. The monomer (i) is preferably acrylic acid, methacrylic acid, maleic acid, and salts thereof, and more preferably acrylic acid, methacrylic acid, and salts thereof.

[0039] (Examples of Monomer (II-3) Other than Monomer Represented by General Formula (3)) A monomer represented by general formula (4): [ka] (In the general formula (4), X represents a -CH2-, -C(CH3)-, or -SO2- group. Each R independently represents -CH3 or -H.)

[0040] Examples of the monomer represented by the general formula (4) include 3- and 3'-allyl-substituted bisphenols such as 4,4'-dihydroxydiphenylpropane, 4,4'-dihydroxydiphenylmethane, and 4,4'-dihydroxydiphenylsulfone.

[0041] A monomer represented by general formula (5): [ka] (In the general formula (5), X represents a -CH2-, -C(CH3)-, or -SO2- group. R represents -CH3 or -H.)

[0042] Examples of the monomer represented by the above general formula (5) include 3-allyl-substituted bisphenols such as 4,4'-dihydroxydiphenylpropane, 4,4'-dihydroxydiphenylmethane, and 4,4'-dihydroxydiphenylsulfone.

[0043] A monomer represented by general formula (6): [ka] (In the general formula (6), R represents -CH3 or -H.)

[0044] An example of the monomer represented by the general formula (6) is allylphenol.

[0045] Half esters and diesters of unsaturated dicarboxylic acids, such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, and citraconic acid, with alcohols having 1 to 30 carbon atoms;

[0046] Half amides and diamides of the above unsaturated dicarboxylic acids with amines having 1 to 30 carbon atoms;

[0047] half esters, half amides, diesters and diamides of (poly)oxyalkylene alkyl ethers or (poly)oxyalkylene alkyl amines in which 1 to 500 moles of alkylene oxide having 2 to 18 carbon atoms are added to alcohols or amines having 1 to 30 carbon atoms, and unsaturated dicarboxylic acids such as (meth)acrylic acid;

[0048] Half esters and diesters of the above unsaturated dicarboxylic acids with glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 moles of such glycols added;

[0049] Half amides of maleamic acid and glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 moles of such glycols added;

[0050] (poly)ethylene glycol mono(meth)acrylate, (poly)propylene glycol mono(meth)acrylate, (poly)butylene glycol mono(meth)acrylates in which 1 to 500 moles of alkylene oxide having 2 to 18 carbon atoms are added to unsaturated monocarboxylic acids such as (meth)acrylic acid (excluding monomer (iii));

[0051] (poly)alkylene glycol di(meth)acrylates such as triethylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, and (poly)ethylene glycol (poly)propylene glycol di(meth)acrylate;

[0052] Polyfunctional (meth)acrylates such as hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and trimethylolpropane di(meth)acrylate;

[0053] (Poly)alkylene glycol dimaleates such as triethylene glycol dimaleate and polyethylene glycol dimaleate;

[0054] unsaturated sulfonic acids such as vinyl sulfonate, (meth)allyl sulfonate, 2-(meth)acryloxyethyl sulfonate, 3-(meth)acryloxypropyl sulfonate, 3-(meth)acryloxy-2-hydroxypropyl sulfonate, 3-(meth)acryloxy-2-hydroxypropyl sulfophenyl ether, 3-(meth)acryloxy-2-hydroxypropyloxysulfobenzoate, 4-(meth)acryloxybutyl sulfonate, (meth)acrylamidomethyl sulfonic acid, (meth)acrylamidoethyl sulfonic acid, 2-methylpropanesulfonic acid (meth)acrylamide, and styrenesulfonic acid, as well as their monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts;

[0055] Amides of unsaturated monocarboxylic acids and amines having 1 to 30 carbon atoms, such as methyl (meth)acrylamide;

[0056] vinyl aromatics such as styrene, α-methylstyrene, vinyltoluene, and p-methylstyrene;

[0057] Alkanediol mono(meth)acrylates such as 1,4-butanediol mono(meth)acrylate, 1,5-pentanediol mono(meth)acrylate, and 1,6-hexanediol mono(meth)acrylate;

[0058] Dienes such as butadiene, isoprene, 2-methyl-1,3-butadiene, and 2-chloro-1,3-butadiene;

[0059] Unsaturated amides such as (meth)acrylamide, (meth)acrylalkylamide, N-methylol (meth)acrylamide, and N,N-dimethyl (meth)acrylamide;

[0060] Unsaturated cyanides such as (meth)acrylonitrile and α-chloroacrylonitrile;

[0061] Unsaturated esters such as vinyl acetate and vinyl propionate;

[0062] Unsaturated amines such as aminoethyl (meth)acrylate, methylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, dibutylaminoethyl (meth)acrylate, and vinylpyridine;

[0063] Divinyl aromatics such as divinylbenzene; cyanurates such as triallyl cyanurate;

[0064] Allyls such as (meth)allyl alcohol and glycidyl (meth)allyl ether;

[0065] Vinyl ethers or allyl ethers such as methoxypolyethylene glycol monovinyl ether, polyethylene glycol monovinyl ether, methoxypolyethylene glycol mono(meth)allyl ether, and polyethylene glycol mono(meth)allyl ether;

[0066] Siloxane derivatives such as polydimethylsiloxane propylaminomaleamic acid, polydimethylsiloxane aminopropylene aminomaleamic acid, polydimethylsiloxane bis-(propylaminomaleamic acid), polydimethylsiloxane bis-(dipropyleneaminomaleamic acid), polydimethylsiloxane-(1-propyl-3-acrylate), polydimethylsiloxane-(1-propyl-3-methacrylate), polydimethylsiloxane bis-(1-propyl-3-acrylate), and polydimethylsiloxane bis-(1-propyl-3-methacrylate).

[0067] The monomer (II-3) may be one of the above monomers alone or a combination of two or more of them. When acrylic acid or a salt thereof and methacrylic acid or a salt thereof are used in combination as the monomer (II-3), the weight ratio of acrylic acid or a salt thereof to methacrylic acid or a salt thereof (total of 100% by weight) is usually acrylic acid / methacrylic acid=(1% to 99%) / (99% to 1%), preferably (20% to 60%) / (80% to 40%), more preferably (30% to 50%) / (50% to 70%).

[0068] [1.2 Copolymer salt] Examples of the salt of the copolymer include monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts of the copolymer.

[0069] [1.3 Monomer ratio] When the monomers constituting the copolymer or a salt thereof (A) are taken as 100% by weight, the weight ratios of the respective monomers are, for example, as follows. The weight ratios below usually correspond to the amounts of the monomers blended when the copolymer or a salt thereof (A) is produced.

[0070] The weight ratio of the monomer (I) is usually 1% by weight or more, preferably 10% by weight or more, more preferably 20% by weight or more, even more preferably 30% by weight or more, 40% by weight or more. The upper limit may be 100% by weight or less, and is usually 97% by weight or less, preferably 90% by weight or less, more preferably 80% by weight or less, even more preferably 75% by weight or less. Therefore, it is usually 1 to 97% by weight, preferably 10 to 90% by weight, more preferably 20 to 80% by weight, even more preferably 30 to 80% by weight, 40 to 75% by weight. When the monomer (I) is less than 100% by weight, the remaining weight % represents the ratio of the monomer (II).

[0071] When the monomer (II-1) is contained, the content is usually 1% by weight or more, preferably 5% by weight or more, more preferably 10% by weight or more. The upper limit is usually 97% by weight or less, preferably 80% by weight or less, more preferably 60% by weight or less, even more preferably 40% by weight or less, 30% by weight or less. Therefore, it is usually 1 to 97% by weight, preferably 1 to 80% by weight, more preferably 5 to 60% by weight, even more preferably 5 to 40% by weight, 10 to 30% by weight.

[0072] When the monomer (II-2) is contained, the blending ratio is usually 1% by weight or more, preferably 10% by weight or more, more preferably 15% by weight or more, and even more preferably 20% by weight or more. The upper limit is usually 50% by weight or less, preferably 45% by weight or less, more preferably 40% by weight or less, and even more preferably 35% by weight or less. Therefore, it is usually 1 to 50% by weight, preferably 10 to 45% by weight, more preferably 15 to 40% by weight, and even more preferably 20 to 35% by weight.

[0073] When the monomer (II-3) is contained, the content is usually 1% by weight or more, preferably 3% by weight or more, more preferably 4% by weight or more. The upper limit is usually 50% by weight or less, preferably 40% by weight or less, more preferably 30% by weight or less, even more preferably 20% by weight or less, 10% by weight or less. Therefore, it is usually 1 to 50% by weight, preferably 1 to 40% by weight, more preferably 3 to 30% by weight, even more preferably 3 to 20% by weight, 4 to 10% by weight.

[0074] [1.4 Physical properties of copolymers] -Weight average molecular weight- The weight average molecular weight of the polycarboxylic acid copolymer or its salt is usually 1,000 or more, preferably 3,000 or more, more preferably 5,000 or more. The upper limit is usually 100,000 or less, preferably 95,000 or less, more preferably 90,000 or less. This makes it possible to suppress aggregation and avoid a decrease in workability. Therefore, it is usually 1,000 to 100,000, preferably 3,000 to 95,000, more preferably 5,000 to 90,000.

[0075] -Mw / Mn- The molecular weight distribution (Mw / Mn) of the polycarboxylic acid copolymer or its salt is usually 1.01 or more, preferably 1.3 or more, more preferably 1.8 or more. The upper limit is usually 10.0 or less, preferably 9.5 or less, more preferably 9.0 or less. Therefore, it is usually 1.01 to 10.0, preferably 1.3 to 9.5, more preferably 1.5 to 9.0.

[0076] [1.5 Method for producing copolymer] The copolymer may be produced by any method as long as it is a method of copolymerizing monomers from which each structural unit is derived, such as polymerization in a solvent or bulk polymerization.

[0077] Examples of the solvent used in the polymerization in a solvent include water, lower alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, etc., aromatic hydrocarbons such as benzene, toluene, xylene, etc., aliphatic hydrocarbons such as cyclohexane, n-hexane, etc., esters such as ethyl acetate, etc., ketones such as acetone, methyl ethyl ketone, etc. From the viewpoint of the solubility of the raw material monomers and the resulting copolymer, it is preferable to use one or more selected from the group consisting of water and lower alcohols, and among them, it is more preferable to use water.

[0078] When copolymerization is carried out in a solvent, each monomer and the polymerization initiator may be continuously added dropwise to a reaction vessel, or a mixture of each monomer and the polymerization initiator may be continuously added dropwise to a reaction vessel. Alternatively, a solvent may be charged into a reaction vessel, and a mixture of the monomers and the solvent and a polymerization initiator solution may be continuously added into the reaction vessel, or a part or all of the monomers may be charged into a reaction vessel, and the polymerization initiator may be continuously added dropwise.

[0079] Examples of polymerization initiators that can be used in copolymerization include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate when copolymerization is performed in an aqueous solvent; and water-soluble organic peroxides such as t-butyl hydroperoxide. In this case, accelerators such as sodium hydrogen sulfite and Mohr's salt can be used in combination. In addition, when copolymerization is performed in a solvent such as a lower alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, an ester, or a ketone, for example, peroxides such as benzoyl peroxide and lauryl peroxide; hydroperoxides such as cumene peroxide; and aromatic azo compounds such as azobisisobutyronitrile can be used as polymerization initiators. In this case, accelerators such as amine compounds can be used in combination. Furthermore, when copolymerization is performed in a water-lower alcohol mixed solvent, the above-mentioned polymerization initiators or combinations of polymerization initiators and accelerators can be appropriately selected and used. The polymerization temperature varies depending on the polymerization conditions such as the solvent used and the type of polymerization initiator, but is usually performed in the range of 50 to 120°C.

[0080] In the copolymerization, the molecular weight can be adjusted by using a chain transfer agent as necessary. Examples of the chain transfer agent used include known thiol compounds such as mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate, and 2-mercaptoethanesulfonic acid; phosphorous acid, hypophosphorous acid, and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionous acid, metabisulfite, and salts thereof (sodium sulfite, potassium sulfite, sodium hydrogen sulfite, potassium hydrogen sulfite, sodium dithionite, potassium dithionite, sodium metabisulfite, potassium metabisulfite, etc.), and lower oxides and salts thereof. These may be used alone or in combination of two or more. Furthermore, a monomer (V) with high chain transfer properties (for example, a (meth)allylsulfonic acid (salt)-based monomer) may be used to adjust the molecular weight of the copolymer. The content of the monomer (V) in the polycarboxylic acid copolymer or its salt (A) is usually 20% by weight or less, and preferably 10% by weight or less. The above content is the content when the content of the monomer (I) + content of the monomer (II) + content of the monomer (III) + content of the monomer (IV) = 100% by weight.

[0081] When copolymerization is performed in an aqueous solvent to obtain a copolymer, the pH during polymerization is usually strongly acidic due to the influence of the monomer having an unsaturated bond, but this may be adjusted to an appropriate pH. If pH adjustment is required during polymerization, the pH can be adjusted using an acidic substance such as phosphoric acid, sulfuric acid, nitric acid, alkyl phosphoric acid, alkyl sulfuric acid, alkyl sulfonic acid, or (alkyl)benzenesulfonic acid. Among these acidic substances, phosphoric acid is preferably used because of its pH buffering effect. However, in order to eliminate the instability of the ester bond of the ester monomer, it is preferable to perform polymerization at a pH of 2 to 7. There is no particular limitation on the alkaline substance that can be used to adjust the pH, but alkaline substances such as NaOH and Ca(OH)2 are common. The pH adjustment may be performed on the monomer before polymerization, or on the copolymer solution after polymerization. In addition, a part of the alkaline substance may be added before polymerization to perform polymerization, and then the pH of the copolymer may be further adjusted.

[0082] [1.6 Optional components of anti-stripping agent] The anti-stripping agent may contain an optional component, such as an anti-stripping component other than the copolymer, a solvent, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a flame retardant, a plasticizer, a pigment, a dye, a dye dispersant, a chelating agent, an unreacted monomer (i) to (iii), a homopolymer of any one of the monomers (i) to (iii), a copolymer of two selected from the monomers (i) to (iii), and the like.

[0083] [2. Use of anti-stripping agents] The anti-stripping agent can provide an anti-stripping effect by adding it to an asphalt composition, and therefore can be used as an anti-stripping agent for an asphalt composition.

[0084] [2.1 Asphalt composition] An asphalt composition (asphalt mixture, asphalt mixture) usually contains asphalt and aggregate. The asphalt composition is usually used in at least one of the surface layer and the base layer of asphalt pavement (surface layer, base layer, and roadbed).

[0085] -asphalt- Asphalt (bituminous material) may be any of, for example, straight asphalt and modified asphalt (polymer modified asphalt, semi-blown asphalt, and hard asphalt).

[0086] -aggregate- The asphalt composition usually contains aggregate. Examples of aggregate include crushed stone, crushed rock, boulders, gravel, sand, crusher run, recycled aggregate, and ceramics. The aggregate usually contains a combination of fine aggregate and coarse aggregate. Examples of fine aggregate include aggregates with relatively small particle size (e.g., aggregates with particle size of 2.36 mm or less and 0.075 mm or more), such as river sand, dune sand, mountain sand, sea sand, crushed sand, fine sand, screenings, crushed stone dust, silica sand, artificial sand, glass cullet, casting sand, and recycled aggregate crushed sand. Examples of coarse aggregate include aggregates with relatively large particle size (e.g., aggregates with particle size of more than 2.36 mm), such as crushed stone. The aggregate may further contain a filler (smaller than fine aggregate, for example, aggregates with particle size of less than 0.075 mm). The particle size of aggregate aggregate can be measured according to the definition of particle size in JIS A5001:1995. The weight ratio of the fine aggregate, the coarse aggregate, and the filler is not particularly limited.

[0087] -Components other than asphalt and aggregate- The asphalt composition may contain components other than asphalt and aggregate, such as fillers (e.g., stone powder), recycled asphalt aggregates (e.g., crushed and decomposed products of used asphalt), emulsifiers, solvents (e.g., water), pigments, and synthetic rubber.

[0088] -Asphalt emulsion composition- The asphalt composition may be an asphalt emulsion composition. In this specification, the asphalt emulsion composition is a composition containing asphalt, aggregate, an emulsifier, and a solvent. In the asphalt emulsion composition, the asphalt is usually dispersed in the solvent, and preferably, the dispersed state can be maintained at room temperature. The asphalt emulsion composition can be used for surface treatment of each layer in an asphalt pavement (improving properties such as adhesion and waterproofness).

[0089] [2.2 Amount of anti-stripping agent used] The amount of the anti-stripping agent (calculated as the amount of the (co)polymer or its salt (A)) in the asphalt composition (100% by weight) is usually 1% by weight or more, preferably 3% by weight or more, more preferably 5% by weight or more. The upper limit is usually 20% by weight or less, preferably 15% by weight or less, more preferably 10% by weight or less.

[0090] The amount of aggregate in the asphalt composition (100% by weight) is usually 1,000% by weight or more, preferably 1,200% by weight or more, and more preferably 1,400% by weight or more. The upper limit is usually 3,000% by weight or less, preferably 2,500% by weight or less, and more preferably 2,000% by weight or less. By being in the above range, the durability of the pavement laminate can be improved.

[0091] [2.3 Manufacturing method of asphalt composition] The asphalt composition can be produced by adding each of the raw materials constituting the asphalt composition (asphalt, aggregate, and components used as necessary) all at once or successively and mixing them. Mixing is usually performed under heated conditions. The heating temperature is usually 120°C or higher, preferably 140°C or higher. The upper limit is usually 220°C or lower, preferably 200°C or lower.

[0092] [2.4 Asphalt pavement laminate] The asphalt composition can be used to form a surface layer and / or a base layer constituting an asphalt pavement laminate. The asphalt pavement laminate has a laminated structure in which, from the bottom, a roadbed, a base layer, and a surface layer are laminated. A layer containing an asphalt emulsion composition may be formed on the surface of the surface layer, between the surface layer and the base layer, and / or between the base layer and the roadbed. Examples of methods for producing pavement laminates include a method in which a base layer is formed on the surface of a roadbed, and a surface layer is formed on the surface of the base layer, and an example is as follows. First, a roadbed is formed by laying crushed stones, gravel, etc. on a roadbed formed by digging down the road surface and laying sand, etc. The roadbed may be formed in two layers, for example, a method in which a lower roadbed is formed by laying large crushed stones, and then an upper roadbed is formed by laying relatively small crushed stones. When forming a roadbed, compaction may be performed using equipment such as a rolling vehicle as necessary. Subsequently, a base layer is formed on the roadbed. The base layer can be formed, for example, by spreading a heated asphalt composition on the roadbed and compacting it using equipment such as a rolling vehicle as necessary. The surface layer is then formed on the base layer. The surface layer can be formed, for example, by spreading a heated asphalt composition on the base layer and compacting it using equipment such as a rolling vehicle as necessary. It is preferable to maintain a high temperature during the work of forming the base layer and surface layer. The heating temperature is usually 120°C or higher, preferably 140°C or higher. The upper limit is usually 220°C or lower, preferably 200°C or lower. When a layer containing an asphalt emulsion composition is formed, for example, after the roadbed, base layer, or surface layer is formed, the asphalt emulsion composition is spread on the layer surface, and if necessary, it is cured with aggregate such as sand, and the upper layer is constructed in sequence. EXAMPLES

[0093] The present invention will be described below with reference to examples. The present invention is not limited to the following examples. In the following examples, "parts" refers to "parts by weight" unless otherwise specified.

[0094] Example 1 164 parts of water was added to a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, and a dropping device, and the temperature was raised to 100° C. with stirring, and then an aqueous monomer solution containing 169 parts of 2-hydroxypropyl acrylate and 112 parts of water, and a mixed solution containing 1 part of ammonium persulfate and 41 parts of water were continuously dropped into the reaction vessel held at 100° C. for 2 hours each. After the dropping was completed, the mixture was reacted for another hour while maintaining the temperature at 100° C., to obtain copolymer a-1.

[0095] The copolymer in the liquid had a weight average molecular weight of 11,300 and Mw / Mn of 2.9.

[0096] Example 2 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 190 parts of water and 50 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10) were charged and heated to 100°C while stirring, and then an aqueous monomer solution containing 117 parts of 2-hydroxypropyl acrylate and 78 parts of water, and a mixed solution containing 1 part of ammonium persulfate and 44 parts of water were continuously dropped into the reaction vessel kept at 100°C for 30 minutes each. After the dropping was completed, the mixture was reacted for another hour while keeping the temperature at 100°C, to obtain a copolymer a-2.

[0097] The copolymer in the liquid had a weight average molecular weight of 40,100 and Mw / Mn of 4.2.

[0098] Example 3 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 90 parts of water and 22 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10) were added, and the temperature was raised to 100°C while stirring. Then, an aqueous monomer solution containing 11 parts of methacrylic acid, 0.1 parts of acrylic acid, 66 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 25), 108 parts of 2-hydroxypropyl acrylate and 51 parts of water, a mixture of 4 parts of ammonium persulfate and 16 parts of water, and a mixture of 2 parts of 3-mercaptopropionic acid and 42 parts of water were continuously dropped into the reaction vessel kept at 100°C for 2 hours. After the dropping, the temperature was kept at 100°C and the reaction was continued for another 1 hour to obtain copolymer a-3. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-3.

[0099] The copolymer in the liquid had a weight average molecular weight of 21,000 and Mw / Mn of 2.6.

[0100] Example 4 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 90 parts of water and 22 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10) were added, and the temperature was raised to 100°C while stirring. Then, a monomer aqueous solution containing 12 parts of methacrylic acid, 0.2 parts of acrylic acid, 66 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 25), 96 parts of 2-hydroxyethyl acrylate and 84 parts of water was mixed, and a mixture of 3 parts of ammonium persulfate and 16 parts of water and a mixture of 2 parts of 3-mercaptopropionic acid and 42 parts of water were continuously dropped into the reaction vessel kept at 100°C for 2 hours. After the dropwise addition, the temperature was kept at 100°C and the reaction was continued for another 1 hour to obtain copolymer a-4. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-4.

[0101] The copolymer in the liquid had a weight average molecular weight of 30,200 and Mw / Mn of 2.7.

[0102] Example 5 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 256 parts of water and 64 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 35) were added, and the temperature was raised to 100°C while stirring. Then, a monomer aqueous solution containing 10 parts of methacrylic acid, 59 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 25), 96 parts of 2-hydroxyethyl methacrylate and 29 parts of water, a mixed solution of 3 parts of ammonium persulfate and 17 parts of water, and a mixed solution of 2 parts of 3-mercaptopropionic acid and 37 parts of water were continuously dropped into the reaction vessel kept at 100°C for 2 hours. After the dropping was completed, the temperature was kept at 100°C and the reaction was continued for another 1 hour to obtain copolymer a-5. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-5.

[0103] The copolymer in the liquid had a weight average molecular weight of 15,800 and Mw / Mn of 1.8.

[0104] Example 6 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 287 parts of water and 72 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 35) were added, and the temperature was raised to 100°C while stirring. Then, a monomer aqueous solution containing 12 parts of methacrylic acid, 66 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 25), 120 parts of 2-hydroxypropyl methacrylate and 51 parts of water, a mixed solution of 4 parts of ammonium persulfate and 16 parts of water, and a mixed solution of 2 parts of 3-mercaptopropionic acid and 42 parts of water were continuously dropped into the reaction vessel kept at 100°C for 2 hours. After the dropping was completed, the temperature was kept at 100°C and the reaction was continued for another 1 hour to obtain a copolymer a-6. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-6.

[0105] The copolymer in the liquid had a weight average molecular weight of 9,800 and Mw / Mn of 1.9.

[0106] Example 7 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 90 parts of water and 22 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10) were added, and the temperature was raised to 100°C while stirring. Then, an aqueous monomer solution containing 11 parts of methacrylic acid, 66 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 25), 119 parts of 4-hydroxybutyl acrylate and 62 parts of water, a mixture of 4 parts of ammonium persulfate and 16 parts of water, and a mixture of 2 parts of 3-mercaptopropionic acid and 42 parts of water were continuously dropped into the reaction vessel kept at 100°C for 2 hours. After the dropping, the temperature was kept at 100°C and the reaction was continued for another 1 hour to obtain copolymer a-7. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-7.

[0107] The copolymer in the liquid had a weight average molecular weight of 88,000 and Mw / Mn of 8.6.

[0108] Example 8 In a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 80 parts of water and 19 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10) were added, and the temperature was raised to 100°C while stirring. Then, a monomer aqueous solution containing 10 parts of methacrylic acid, 59 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 25), 96 parts of 2-hydroxypropyl acrylate and 51 parts of water, a mixed solution of 3 parts of ammonium persulfate and 17 parts of water, and a mixed solution of 1 part of 3-mercaptopropionic acid and 29 parts of water were continuously dropped into the reaction vessel kept at 100°C for 2 hours. After the dropping was completed, the temperature was kept at 100°C and the reaction was continued for another 1 hour to obtain a copolymer a-8. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-8.

[0109] The copolymer in the liquid had a weight average molecular weight of 45,800 and Mw / Mn of 4.6.

[0110] Example 9 169 parts of water was added to a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, and a dropping device, and the temperature was raised to 100°C while stirring. Then, a monomer aqueous solution containing 39 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 9), 92 parts of 2-hydroxypropyl acrylate, and 86 parts of water, and a mixture of 1 part of ammonium persulfate and 49 parts of water were continuously dropped into the reaction vessel kept at 100°C for 30 minutes. After the dropping was completed, the mixture was reacted for another hour while keeping the temperature at 100°C, to obtain a copolymer a-9.

[0111] The copolymer in the liquid had a weight average molecular weight of 38,300 and Mw / Mn of 4.0.

[0112] Comparative Example 2 A glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, a nitrogen inlet tube and a dropping device was charged with 198 parts of water, the reaction vessel was replaced with nitrogen while stirring, and the temperature was raised to 100° C. under a nitrogen atmosphere. Then, while maintaining the temperature at 100° C., an aqueous monomer solution containing 72 parts of acrylic acid, 70 parts of a 31% NaOH aqueous solution and 54 parts of water, and a mixed solution of 4 parts of ammonium persulfate and 37 parts of water were each dropped over 2 hours. The reaction was continued for another hour while maintaining the temperature at 100° C., to obtain an aqueous solution of polymer b-1.

[0113] The polymer in the liquid had a weight average molecular weight of 14,000 and Mw / Mn of 1.71.

[0114] Comparative Example 3 7900 kg of water was charged into a stainless steel reaction vessel equipped with a thermometer, a stirrer, a reflux device, a nitrogen inlet tube and a dropping device, and the reaction vessel was replaced with nitrogen under stirring. After heating to 100°C under a nitrogen atmosphere, a monomer aqueous solution containing 2503 g of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 14), 405 kg of methacrylic acid, and 2666 kg of water, and a stirred mixture of 50 kg of sodium persulfate and 500 kg of water were continuously dropped into the reaction vessel held at 100°C over 2 hours. The polymerization reaction was carried out for 1 hour while maintaining the temperature at 100°C. After that, the mixture was cooled to 70°C in an additional device located at the rear of the reaction vessel, and the liquid was neutralized to pH 6 with a 30% NaOH aqueous solution and water was added at the same time to obtain an aqueous solution of the copolymer. The copolymer in the liquid was copolymer (b-2) (weight average molecular weight Mw 19,300, Mw / Mn 1.54).

[0115] [Anti-peeling test] Each sample of the Example and Comparative Examples 2 and 3 was added to asphalt according to the following procedure, and the peeling area was measured. (1) 2.5 g (solid content) (5% by weight based on asphalt) of each copolymer of the examples was added to 50 g of 60-80 straight asphalt, or no copolymer was added (Comparative Example 1), and the mixture was heated to about 150°C to obtain a molten heated asphalt. (2) A marble (approximately 15 mm in diameter) was dropped into the heated asphalt and left to spread for one hour, then removed and allowed to cool naturally. (3) The marbles covered with asphalt were immersed in pure water at 80°C and heated for 3 minutes. (4) The marbles were removed, allowed to dry naturally, and the area that had peeled off was measured.

[0116] [Table 1]

[0117] The peeling area in Comparative Example 1 was 67.4%, and the peeling areas in Comparative Examples 2 and 3 were 70.8% and 68.9%, respectively, which were even higher than Comparative Example 1, whereas the peeling areas in Examples 1 to 9 were reduced to less than half that of Comparative Example 1 (Table 1). This result shows that the anti-stripping agent of the present invention can inhibit peeling of asphalt from aggregate in an asphalt composition.

Claims

1. An anti-stripping agent comprising a (co)polymer of a monomer containing one or more monomers (I) selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, and 2-hydroxybutyl methacrylate, or a salt thereof (A).

2. The (co)polymer or its salt (A) is a copolymer or its salt of a monomer (I) and a copolymerizable monomer (II), The monomer (II) is Monomer (II-1) represented by the following general formula (1), and / or Monomer (II-2) represented by the following general formula (2): The anti-stripping agent according to claim 1 , R １ -O-(A １ O) ｎ１ -R ２ （１） (In the formula, R １ represents an alkenyl group having 2 to 5 carbon atoms. １ O may be the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. n1 is the average number of moles of the oxyalkylene group added and represents a number from 1 to 200. ２ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. 【Chemistry 1】 (In the formula, R ３ , R ４ and R ５ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; and m represents a number from 0 to 2. ２ O may be the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. n2 is the average number of moles of the oxyalkylene group added and represents a number from 1 to 200. X represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.

3. The monomer (II) is The anti-stripping agent according to claim 2, further comprising a monomer (II-3) copolymerizable with the monomers (II-1) and (II-2).

4. The anti-stripping agent according to claim 3, wherein the monomer (II-3) includes a monomer represented by the following general formula (3): 【Chemistry 2】 (In the formula, R ６ ~R ８ each independently represents a hydrogen atom, a methyl group, or -(CH ２ ) ｐ COOM ２ Here, -(CH ２ ) ｐ COOM ２ When it represents a group, -COOM １ group or other -(CH ２ ) ｐ COOM ２ The M group may form an anhydride group. １ and M. ２ each independently represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, or a substituted alkylammonium group; and p represents an integer of 0 to 2.

5. The anti-stripping agent according to any one of claims 1 to 4, wherein the weight ratio of the monomer (I) to 100% by weight of the monomers constituting the copolymer or its salt (A) is 1 to 97% by weight.

6. The anti-stripping agent according to any one of claims 2 to 4, wherein the weight ratio of the monomer (II-1) to 100% by weight of the monomers constituting the copolymer or its salt (A) is 1 to 97% by weight.

7. The anti-stripping agent according to any one of claims 2 to 4, wherein the weight ratio of the monomer (II-2) to 100% by weight of the monomers constituting the copolymer or its salt (A) is 1 to 50% by weight.

8. 5. The anti-stripping agent according to claim 3, wherein the weight ratio of the monomer (II-3) to 100% by weight of the monomers constituting the copolymer or its salt (A) is 1 to 50% by weight.

9. The anti-stripping agent according to any one of claims 1 to 4, wherein the copolymer or salt thereof (A) has a weight average molecular weight Mw of 5,000 to 100,000.

10. 5. The anti-stripping agent according to claim 1, wherein the ratio Mw / Mn of the weight average molecular weight Mw to the number average molecular weight Mn of the copolymer or its salt (A) is 1.01 to 10.

0.

11. An asphalt composition comprising the anti-stripping agent according to any one of claims 1 to 4.

12. The asphalt composition according to claim 11, wherein the content of the anti-stripping agent is 1 to 20 parts by weight per 100 parts by weight of the asphalt-based material.

13. An asphalt emulsion composition comprising the antistripping agent according to any one of claims 1 to 4.

14. 12. An asphalt pavement laminate comprising a surface course, a base course, and a roadbed, wherein any one of the surface course and the base course is a layer comprising the asphalt composition according to claim 11.

15. The laminate according to claim 14, further comprising a layer containing an asphalt emulsion composition containing the anti-stripping agent according to any one of claims 1 to 4 on the surface of the surface layer, between the surface layer and the base layer, and / or between the base layer and the roadbed.

16. 15. A method for producing an asphalt pavement laminate according to claim 14, comprising forming a base layer and a surface layer in that order on a surface of a roadbed, wherein either the surface layer or the base layer is a layer containing the asphalt composition according to claim 11.

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