Acrylic adhesive composition

Abstract

To provide an acrylic adhesive having good adhesiveness to polypropylene.SOLUTION: An acrylic adhesive composition comprising (A) a polymerizable monomer having a (meth) acryloyl group, (B) a chlorosulfonated polyolefin having a weight average molecular weight of 100,000 to 600,000, (C) a chlorosulfonated propylene-based polymer having a weight average molecular weight of 5000 to 60000, (D) an organic peroxide, and (E) a reducing agent.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an acrylic adhesive composition. [Background technology]

[0002] Second-generation acrylic adhesives (hereinafter sometimes referred to as SGA) are two-component acrylic adhesives containing organic peroxides and reducing agents, and the curing process proceeds through the polymerization of (meth)acrylic monomers, initiated by the radicals generated by the reaction of the organic peroxide and reducing agent. Features of SGA include the ability to achieve excellent adhesion even when the mixing ratio of the two components is inaccurate, and the ability to adhere to oily surfaces.

[0003] On the other hand, polypropylene is widely used in a wide range of applications due to its excellent processability, physical properties, recyclability, and price. However, it is a poorly adhesive material, and it is difficult to ensure sufficient adhesive strength even with surface treatments.

[0004] As a method for improving adhesion to polypropylene, a method of treating the polypropylene substrate in advance with a primer consisting of atactic polypropylene and an organic solvent has been proposed (see, for example, Patent Document 1). However, the method of treating the polypropylene substrate in advance has had problems such as making the production process complicated. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-199119 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above problems, and an object of the present invention is to provide an acrylic adhesive composition that exhibits adhesion to polypropylene without requiring any special pretreatment. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to solve the above problems and have completed the present invention, which relates to the following [1] to

[11] . [1] An acrylic adhesive composition comprising: (A) a polymerizable monomer having a (meth)acryloyl group; (B) a chlorosulfonated polyolefin having a weight-average molecular weight of 100,000 to 600,000; (C) a chlorosulfonated propylene polymer having a weight-average molecular weight of 3,000 to 80,000; (D) an organic peroxide; and (E) a reducing agent. [2] The acrylic adhesive composition according to [1], which is a two-component type comprising: (A) a polymerizable monomer having a (meth)acryloyl group; (B) a chlorosulfonated polyolefin having a weight-average molecular weight of 100,000 to 600,000; (C) a chlorosulfonated propylene polymer having a weight-average molecular weight of 3,000 to 80,000; and (D) a liquid A containing an organic peroxide; and (E) a liquid B containing a reducing agent. [3] The acrylic adhesive composition according to [1] or [2], wherein the content of component (A) is 40 to 85 parts by weight, and the total content of components (B) and (C) is 15 to 60 parts by weight (the total of components (A), (B), and (C) is 100 parts by weight), and the content of component (C) in components (B) and (C) is 5 to 80% by weight. [4] The acrylic adhesive composition according to any one of [1] to [3], wherein the component (A) contains at least (meth)acrylic acid. [5] The acrylic adhesive composition according to any one of [1] to [4], wherein component (B) is at least one chlorosulfonated polyolefin selected from the group consisting of chlorosulfonated polyethylene, alkylated chlorosulfonated polyethylene, and chlorosulfonated propylene polymers. [6] The acrylic adhesive composition according to any one of [1] to [5], wherein the chlorine content of component (B) is 20.0 to 50.0 wt %. [7] The acrylic adhesive composition according to any one of [1] to [6], wherein the sulfur content of component (B) is 0.3 to 5.0 wt %. [8] The acrylic adhesive composition according to any one of [1] to [7], wherein component (C) is a chlorosulfonated polypropylene or a chlorosulfonated propylene-ethylene copolymer. [9] The acrylic adhesive composition according to any one of [1] to [8], wherein the chlorine content of component (C) is 18.0 to 40.0 wt %.

[10] The acrylic adhesive composition according to any one of [1] to [9], wherein the sulfur content of component (C) is 0.3 to 5.0 wt %.

[11] An adhesive using the acrylic adhesive composition according to any one of [1] to

[10] . [Effects of the Invention]

[0008] The acrylic adhesive composition of the present invention can exhibit adhesive properties to polypropylene without requiring any special pretreatment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described in detail below.

[0010] In the present invention, "(meth)acrylic" refers to "acrylic" and / or "methacrylic", and "(meth)acrylate" refers to "acrylate" and / or "methacrylate". Furthermore, "(meth)acryloyl group" refers to "acryloyl group" and / or "methacryloyl group", which is a functional group represented by CH2=C(R)-C(=O)- (R is a hydrogen atom or a methyl group).

[0011] An acrylic adhesive composition according to one embodiment of the present invention is an acrylic adhesive composition containing (A) a polymerizable monomer having a (meth)acryloyl group, (B) a chlorosulfonated polyolefin having a weight-average molecular weight of 100,000 to 600,000, (C) a chlorosulfonated propylene polymer having a weight-average molecular weight of 5,000 to 60,000, (D) an organic peroxide, and (E) a reducing agent.

[0012] The acrylic adhesive exhibits excellent adhesive properties and is therefore preferably a two-component type comprising: (A) a polymerizable monomer having a (meth)acryloyl group, (B) a chlorosulfonated polyolefin having a weight-average molecular weight of 100,000 to 600,000, (C) a chlorosulfonated propylene polymer having a weight-average molecular weight of 3,000 to 80,000, and (D) a liquid A containing an organic peroxide; and (E) a liquid B containing a reducing agent.

[0013] Acrylic adhesives exhibit excellent adhesive properties, and therefore preferably contain 40 to 85 parts by weight of component (A) and 15 to 60 parts by weight of the total content of components (B) and (C) (components (B) + (C)); more preferably, component (A) is 45 parts by weight or more and components (B) + (C) is 55 parts by weight or less; even more preferably, component (A) is 50 parts by weight or more and components (B) + (C) is 50 parts by weight or less; particularly preferably, component (A) is 55 parts by weight or more and components (B) + (C) is 45 parts by weight or less; more preferably, component (A) is 80 parts by weight or less and components (B) + (C) is 20 parts by weight or more; and even more preferably, component (A) is 75 parts by weight or less and components (B) + (C) is 25 parts by weight or more. The total amount of components (A), (B), and (C) is 100 parts by weight.

[0014] [Component (A)] The polymerizable monomer having a (meth)acryloyl group of component (A) may be any monomer capable of radical polymerization. Examples of the polymerizable monomer having a (meth)acryloyl group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, and isononyl (meth)acrylate. acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, and adamantyl (meth)acrylate. Alkoxyalkyl (meth)acrylates; alkoxyalkyl (meth)acrylates such as methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, and butoxyethyl (meth)acrylate; hydroxyl group-containing (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 2-hydroxy-3-phenoxypropyl (meth)acrylate; (meth)acrylic acid; ω-carboxy-polycaprolactone mono(meth)acrylate polycaprolactone-modified (meth)acrylic acid esters such as acrylate; (meth)acryloyloxyalkyl dicarboxylic acid monoesters such as 2-(meth)acryloyloxyethyl succinic acid monoester, 2-(meth)acryloyloxyethyl hexahydrophthalic acid monoester, 2-(meth)acryloyloxyethyl phthalic acid monoester, 2-(meth)acryloyloxyethyl-2-hydroxyethyl-phthalic acid monoester, and 2-(meth)acryloyloxyethyl-2-hydroxypropyl-phthalic acid monoester;Alkylene glycol-modified (meth)acrylates such as 2-ethylhexyl diethylene glycol (meth)acrylate; alkoxypolyalkylene glycol-modified (meth)acrylates such as phenoxy polyethylene glycol (meth)acrylate and nonylphenoxy polyethylene glycol (meth)acrylate; ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,3-propylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polycarbonate diol di(meth)acrylate, ε-caprolactone-modified Examples of suitable (meth)acrylates include polyfunctional (meth)acrylates such as tris((meth)acryloxyethyl)isocyanurate, bisphenol A ethylene oxide adduct di(meth)acrylate, and polyester diol di(meth)acrylate; (meth)acrylates having a heterocyclic structure such as glycidyl (meth)acrylate, acryloylmorpholine, and tetrahydrofurfuryl (meth)acrylate; alkoxysilanes having a polymerizable (meth)acryloyl group such as 3-(meth)acryloxypropyltrimethoxysilane; phosphate ester polymerizable monomers such as reaction products of 2-methacryloyloxyethyl acid phosphate and 6-hexanolide addition polymers of 2-hydroxyethyl (meth)acrylate with phosphoric anhydride; and (meth)acrylamide polymerizable monomers such as (meth)acrylamide, N-methylol (meth)acrylamide, and N,N-dimethylacrylamide. These may be used alone or in combination of two or more.

[0015] It is preferable that component (A) contains (meth)acrylic acid, as this results in an excellent curing rate. The content of (meth)acrylic acid is preferably 3 parts by weight or more, more preferably 5 parts by weight or more, and even more preferably 8 parts by weight or more, as this results in an excellent curing rate. Furthermore, the content of (meth)acrylic acid is preferably 30 parts by weight or less, more preferably 25 parts by weight or less, even more preferably 20 parts by weight or less, and particularly preferably 15 parts by weight or less, as this results in excellent solubility of the chlorosulfonated polyolefin and chlorosulfonated propylene polymer.

[0016] [(B) Component] The chlorosulfonated polyolefin of component (B) refers to a polyolefin having at least chlorine and chlorosulfone groups bonded to the main chain skeleton of the polyolefin.

[0017] The method for obtaining the chlorosulfonated polyolefin is not particularly limited, and the polyolefin can be produced by a conventionally known method.

[0018] The weight-average molecular weight of the chlorosulfonated polyolefin is 100,000 or more, preferably 120,000 or more, more preferably 150,000 or more, and even more preferably 170,000 or more, because it provides excellent polymer strength. Also, because it provides excellent solubility in (meth)acrylates, it is 600,000 or less, preferably 550,000 or less, more preferably 500,000 or less, even more preferably 450,000 or less, and particularly preferably 400,000 or less.

[0019] The chlorosulfonated polyolefin is preferably at least one chlorosulfonated polyolefin selected from the group consisting of chlorosulfonated polyethylene, alkylated chlorosulfonated polyethylene, and chlorosulfonated propylene copolymer, as this provides excellent adhesive properties.

[0020] Chlorosulfonated polyethylene is a chlorosulfonated polyolefin whose main chain skeleton is polyethylene. Examples of polyethylene include high-density polyethylene, low-density polyethylene, and linear low-density polyethylene.

[0021] Alkylated chlorosulfonated polyethylene is a chlorosulfonated polyethylene to which an alkyl group is bonded. For example, alkylated chlorosulfonated polyethylene is sold by Tosoh Corporation under the trade name Extos (registered trademark).

[0022] Chlorosulfonated propylene copolymers are chlorosulfonated propylene copolymers whose main chain skeleton is a propylene copolymer. The propylene polymer referred to here refers to a polymer containing primarily propylene as a monomer unit. Examples of propylene polymers include propylene homopolymers, propylene-ethylene copolymers such as random polypropylenes in which ethylene is randomly copolymerized and block polypropylenes in which ethylene is block copolymerized, polypropylene terpolymers in which ethylene and an α-olefin are copolymerized, syndiotactic polypropylene, atactic polypropylene, and long-chain branched polypropylene. Examples of α-olefins copolymerized into polypropylene terpolymers include 1-butene, 1-pentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene. Because of their excellent adhesion to polypropylene, propylene homopolymers and propylene-ethylene copolymers are preferred.

[0023] The chlorine content of the chlorosulfonated polyolefin is preferably 20.0% by weight or more, more preferably 22.0% by weight or more, even more preferably 24.0% by weight or more, and particularly preferably 25.0% by weight or more, because it provides excellent solubility in component (A). Also, because it provides excellent adhesion to polypropylene, it is preferably 50.0% by weight or less, more preferably 48.0% by weight or less, even more preferably 46.0% by weight or less, and particularly preferably 45.0% by weight or less.

[0024] The sulfur content of the chlorosulfonated polyolefin is preferably 0.3% by weight or more, more preferably 0.4% by weight or more, even more preferably 0.5% by weight or more, and particularly preferably 0.6% by weight or more, because this results in an excellent curing rate. Also, because the storage stability of Solution A is excellent, the sulfur content is preferably 5.0% by weight or less, more preferably 4.0% by weight or less, even more preferably 3.5% by weight or less, and particularly preferably 3.0% by weight or less.

[0025] The chlorosulfonated polyolefin constituting component (B) may be a single type, or a combination of two or more types. Methods for using a combination of multiple chlorosulfonated polyolefins include using multiple polyolefins when producing the chlorosulfonated polyolefin, mixing chlorosulfonated propylene polymers with different chlorine or sulfur contents, mixing when preparing an adhesive composition, and combinations of these methods.

[0026] [(C) component] The chlorosulfonated propylene polymer of component (C) refers to a propylene polymer to which at least chlorine and chlorosulfone groups are bonded.

[0027] The method for obtaining the chlorosulfonated propylene polymer is not particularly limited, and the polymer can be produced by a conventionally known method.

[0028] The weight-average molecular weight of the chlorosulfonated propylene polymer is 3,000 or more, preferably 4,000 or more, more preferably 5,000 or more, and even more preferably 7,000 or more, because the polymer strength is excellent. Also, the weight-average molecular weight is 80,000 or less, preferably 75,000 or less, more preferably 65,000 or less, even more preferably 60,000 or less, and particularly preferably 55,000 or less, because the adhesiveness to polypropylene is excellent.

[0029] Examples of propylene-based polymers that form the main chain skeleton of chlorosulfonated propylene-based copolymers include propylene homopolymers, propylene-ethylene copolymers such as random polypropylenes in which ethylene is randomly copolymerized and block polypropylenes in which ethylene is block copolymerized, polypropylene terpolymers in which ethylene and an α-olefin are copolymerized, syndiotactic polypropylene, atactic polypropylene, and long-chain branched polypropylene. Examples of α-olefins copolymerized into polypropylene terpolymers include 1-butene, 1-pentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene. Because of their excellent adhesion to polypropylene, propylene homopolymers and propylene-ethylene copolymers are preferred as propylene-based polymers.

[0030] The crystalline melting point of the propylene polymer that is the main chain skeleton of the chlorosulfonated propylene copolymer is preferably 40° C. or higher, more preferably 60° C. or higher, even more preferably 80° C. or higher, and particularly preferably 100° C. or higher, because it provides excellent adhesion to polypropylene. Also, it is preferably 180° C. or lower, more preferably 170° C. or lower, because it provides excellent solubility in component (A).

[0031] The chlorine content of the chlorosulfonated propylene polymer is preferably 18.0% by weight or more, more preferably 19.0% by weight or more, even more preferably 20.0% by weight or more, and particularly preferably 22.0% by weight or more, because it has excellent solubility in component (A). Also, because it has excellent adhesion to polypropylene, the chlorine content is preferably 40.0% by weight or less, more preferably 38.0% by weight or less, even more preferably 36.0% by weight or less, and particularly preferably 35.0% by weight or less.

[0032] The sulfur content of the chlorosulfonated propylene polymer is preferably 0.3% by weight or more, more preferably 0.4% by weight or more, even more preferably 0.5% by weight or more, and particularly preferably 0.6% by weight or more, because this results in an excellent curing rate. Also, because the storage stability of Solution A is excellent, the sulfur content is preferably 5.0% by weight or less, more preferably 4.0% by weight or less, even more preferably 3.5% by weight or less, and particularly preferably 3.0% by weight or less.

[0033] The chlorosulfonated propylene polymer constituting component (C) may be a single type, or a combination of two or more types. Methods for using a combination of multiple chlorosulfonated propylene polymers include using multiple propylene polymers when producing a chlorosulfonated propylene polymer, mixing chlorosulfonated propylene polymers with different chlorine or sulfur contents, mixing when preparing an adhesive composition, and combinations of these methods.

[0034] [(D) component] The organic peroxide of component (D) is an organic compound having an -OO- bond in the molecule, and is not particularly limited as long as it acts as a radical polymerization initiator for component (A). Examples of organic peroxides include dibenzoyl peroxide, 1,1-di(t-butylperoxy)cyclohexane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxylaurate, t-butylperoxyisopropyl monocarbonate, t-hexylperoxybenzoate, t-butylperoxybenzoate, 2,2-di(t-butylperoxy)butane, t-butylperoxyacetate, dicumyl peroxide, di-t-hexylperoxybenzoate, 2,2-di(t-butylperoxy)butane, t-butylperoxyacetate, dicumyl peroxide, di-t-hexylperoxybenzoate, di-t-butyl ... Examples of organic peroxides include 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, 2,3-dimethyl-2,3-diphenylbutane, etc. These organic peroxides may be used alone or in combination of two or more.

[0035] The one-hour half-life temperature of the organic peroxide is preferably 80°C or higher, more preferably 100°C or higher, for ease of handling, and is preferably 300°C or lower, more preferably 250°C or lower, for excellent curability.

[0036] The content of organic peroxide in the acrylic adhesive is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, and even more preferably 0.5 parts by weight or more, per 100 parts by weight of the total of components (A), (B), and (C) ((A) + (B) + (C)), since this provides excellent curing properties. Furthermore, since this provides excellent storage stability for solution A, the content is preferably 10 parts by weight or less, more preferably 8 parts by weight or less, and even more preferably 5 parts by weight or less, per 100 parts by weight of (A) + (B) + (C). [Component (E)] The reducing agent (E) is a compound with reducing properties. To obtain excellent curing properties, a reducing agent that forms a redox catalyst system with the organic peroxide (D) is preferred. Examples of reducing agents include thiourea derivatives, reaction products of aldehydes and amines, and metal compounds. The reducing agents may be used alone or in combination of two or more.

[0037] Examples of thiourea derivatives include 2-mercaptobenzimidazole, methylthiourea, dibutylthiourea, tetramethylthiourea, and ethylenethiourea.

[0038] The reaction product of an aldehyde and an amine is a reaction product obtained by reacting an aldehyde with an amine. The aldehyde in the reaction product of an aldehyde and an amine is preferably an aliphatic aldehyde having 1 to 12 carbon atoms, as this facilitates the formation of a redox catalyst. Examples of aldehydes include acetaldehyde, butyraldehyde, propionaldehyde, cyclopentanal, hexanal, cyclohexanal, hydrocinnamaldehyde, heptanal, decanal, and dodecanal. The amine in the reaction product of an aldehyde and an amine is preferably a primary amine having 1 to 18 carbon atoms, as this facilitates the formation of a redox catalyst, and more preferably an aromatic amine. Examples of amines include ethylamine, butylamine, pentylamine, cyclopentylamine, hexylamine, cyclohexylamine, octylamine, decylamine, dodecylamine, hexadecylamine, octadecylamine, aniline, xylylamine, 4-methylaniline, 3-methylaniline, 2-methylaniline, 2,4-dimethylaniline, 2,6-dimethylaniline, 2,4,6-trimethylaniline, 4-ethylaniline, 3-ethylaniline, 2-ethylaniline, 2,4-diethylaniline, 2,6-dimethylaniline, 2,4,6-triethylaniline, 4-isopropylaniline, 3-isopropylaniline, 2-isopropylaniline, 2,4-diisopropylaniline, 2,6-diisopropylaniline, 2-methoxyaniline, 3-methoxyaniline, 4-methoxyaniline, 2-ethoxyaniline, 3-ethoxyaniline, and 4-ethoxyaniline.

[0039] Examples of metal compounds include compounds containing cobalt, copper, and vanadium, and more specifically, examples thereof include cobalt naphthenate, copper naphthenate, vanadyl acetylacetonate, vanadyl stearate, vanadium naphthenate, vanadium acetylacetonate, and vanadium benzoylacetonate.

[0040] Of these, from the viewpoint of curability, a reaction product of an aldehyde with an amine is preferred, and a reaction product of butyraldehyde with aniline is more preferred.

[0041] [Other ingredients] The acrylic adhesive may contain additives such as antioxidants, acid acceptors, plasticizers, viscosity modifiers, flexibility imparting agents, inorganic fillers, silane coupling agents, pigments, etc. The amounts of these additives may be conventional amounts as long as they do not deviate from the object of the present invention.

[0042] [glue] The acrylic adhesive composition can be used as an adhesive having excellent adhesive properties to polypropylene. [Example]

[0043] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0044] The chlorine content, sulfur content and molecular weight of the chlorosulfonated propylene polymers in the examples were measured as follows.

[0045] [Measurement of chlorine content and sulfur content] The chlorine content of chlorosulfonated polyolefin was determined by burning the sample using the combustion flask method, absorbing the resulting hydrochloric acid in pure water, and then quantifying it with an automatic titrator using a 0.05 mol / L silver nitrate solution. The sulfur content was measured using the oxygen combustion flask method in accordance with JIS K6233 (1998 edition).

[0046] [Molecular weight measurement] The molecular weight of the polymer solution obtained by dissolving the chlorosulfonated polyolefin in a measurement solvent was measured by GPC. The number average molecular weight (Mn) and weight average molecular weight (Mw) were calculated in terms of polystyrene using standard polystyrene (manufactured by Tosoh Corporation).

[0047] Synthesis Examples 1 to 5 were synthesized by the following methods.

[0048] [Raw materials] The following commercially available products were used as raw materials for the synthesis of the chlorosulfonated propylene polymers.

[0049] PP1: Polypropylene (manufactured by Sanyo Chemical Industries, Ltd., trade name: Viscol (registered trademark) 660-P, crystalline melting point: 136°C) PP2: Random polypropylene (manufactured by Japan Polypropylene, product name: Novatec (registered trademark) MG03BD, crystalline melting point: 153°C, melt mass-flow rate (JIS K 7210): 30 g / 10 min) PP3: Block polypropylene (manufactured by Japan Polypropylene Corporation, product name: Novatec (registered trademark) BC03B, crystalline melting point: 165°C, melt mass-flow rate (JIS K 7210): 30 g / 10 min) Sulfuryl chloride (Fujifilm Wako Pure Chemical Industries, Ltd.) α,α'-Azobisisobutyronitrile (Fujifilm Wako Pure Chemical Industries, Ltd.) Pyridine (Fujifilm Wako Pure Chemical Industries, Ltd.) 1,1,2-Trichloroethane (Tokyo Chemical Industry Co., Ltd.) [Synthesis of chlorosulfonated propylene polymer] Under a nitrogen atmosphere, a propylene-based polymer and 1,1,2-trichloroethane were added to a glass pressure reactor according to Table 1 and dissolved at 130°C. After dissolution was complete, the reaction solution was cooled to 120°C. Pyridine was added to this polymer solution according to Table 1. At 120°C, a 1,1,2-trichloroethane solution of α,α'-azobisisobutyronitrile adjusted to 2 g / L was added dropwise at a rate of 0.1 mL / min, while sulfuryl chloride was added at a rate of 0.8 mL / min, and the pressure was adjusted to 0.25 MPaG. After sulfuryl chloride was added for the specified time according to Table 1, the temperature and pressure were lowered, and nitrogen gas was introduced at a rate of 150 mL / min at 100°C and atmospheric pressure for 1 hour. The solvent was distilled off from the resulting reaction solution to obtain a chlorosulfonated propylene-based polymer.

[0050] [Table 1]

[0051] In Examples 1 to 6 and Comparative Examples 1 to 6, the adhesiveness was evaluated by the following method.

[0052] [Raw materials] Methyl methacrylate (Fujifilm Wako Pure Chemical Industries, Ltd.) Methacrylic acid (Fujifilm Wako Pure Chemical Industries, Ltd.) TS-340: Chlorosulfonated polyethylene (manufactured by Tosoh Corporation, trade name: TOSO-CSM (registered trademark) TS-340)

[0053] [Table 2]

[0054] Acid acceptor: Bisphenol A diglycidyl ether (Fujifilm Wako Pure Chemical Industries, Ltd.) BHT: 2,6-di-t-butyl-4-methylphenol (Fujifilm Wako Pure Chemical Industries, Ltd.) Organic peroxide: cumene hydroperoxide (80%, manufactured by Tokyo Chemical Industry Co., Ltd.) Reducing agent: reaction product of n-butylaldehyde and aniline (manufactured by Ouchi Shinko Chemical Industry Co., Ltd., trade name: Noccela 8) [Preparation of adhesive composition] Solution A was prepared by placing the ingredients listed in Tables 3 and 4 in a mayonnaise bottle, sealing it, and mixing it in a ball mill. Solution B was prepared by using a commercially available reducing agent as is.

[0055] [Adhesion evaluation] Liquids A and B were weighed out in the mixing ratios shown in Tables 3 and 4 and mixed with a spatula. The mixed adhesive composition was uniformly applied to a 25 mm x 12.5 mm area of ​​a polypropylene substrate (3 mm thick x 25 mm wide x 100 m long), and pieces of the same material were bonded together. 0.25 mm glass beads were sprinkled on the adhesive composition to prepare an adhesive test piece with an adhesive layer thickness of 0.25 mm.

[0056] The prepared adhesive test pieces were left to stand for at least one day in an environment of 23°C and 50% RH, and the tensile shear adhesive strength was measured at a pulling rate of 50 mm / min in accordance with JIS K 6850.

[0057] As can be seen from Table 3, Examples 1 to 6 all had tensile shear adhesive strengths to polypropylene substrates exceeding 1 MPa, indicating good adhesion to polypropylene substrates. On the other hand, as can be seen from Table 4, Comparative Examples 1 to 5 all had tensile shear adhesive strengths to polypropylene substrates below 1 MPa, indicating poor adhesion to polypropylene substrates. Comparative Example 5 had no fluidity at room temperature, making it impossible to evaluate the adhesive.

[0058] [Table 3]

[0059] [Table 4] [Industrial Applicability]

[0060] The acrylic adhesive composition of the present invention can be used in the same manner as conventionally known acrylic adhesives, and can provide an acrylic adhesive that has good adhesion to polypropylene.

Claims

1. An acrylic adhesive composition comprising: (A) a polymerizable monomer having a (meth)acryloyl group; (B) a chlorosulfonated polyolefin having a weight-average molecular weight of 100,000 to 600,000; (C) a chlorosulfonated propylene-based polymer having a weight-average molecular weight of 3,000 to 80,000; (D) an organic peroxide; and (E) a reducing agent.

2. 2. The acrylic adhesive composition according to claim 1, which is a two-component type comprising: a liquid A containing (A) a polymerizable monomer having a (meth)acryloyl group, (B) a chlorosulfonated polyolefin having a weight-average molecular weight of 100,000 to 600,000, (C) a chlorosulfonated propylene-based polymer having a weight-average molecular weight of 3,000 to 80,000, and (D) an organic peroxide; and a liquid B containing (E) a reducing agent.

3. 2. The acrylic adhesive composition according to claim 1, wherein the content of component (A) is 40 to 85 parts by weight, and the total content of components (B) and (C) is 15 to 60 parts by weight (the total of components (A), (B), and (C) is 100 parts by weight), and the content of component (C) in components (B) and (C) is 5 to 80% by weight.

4. The acrylic adhesive composition according to claim 1, wherein component (A) contains at least (meth)acrylic acid.

5. 2. The acrylic adhesive composition according to claim 1, wherein component (B) is at least one chlorosulfonated polyolefin selected from the group consisting of chlorosulfonated polyethylene, alkylated chlorosulfonated polyethylene, and chlorosulfonated propylene polymers.

6. 2. The acrylic adhesive composition according to claim 1, wherein the chlorine content of component (B) is 20.0 to 50.0% by weight.

7. 2. The acrylic adhesive composition according to claim 1, wherein the sulfur content of component (B) is 0.3 to 5.0% by weight.

8. 2. The acrylic adhesive composition according to claim 1, wherein component (C) is a chlorosulfonated polypropylene or a chlorosulfonated propylene-ethylene copolymer.

9. 2. The acrylic adhesive composition according to claim 1, wherein the chlorine content of component (C) is 18.0 to 40.0 wt %.

10. 2. The acrylic adhesive composition according to claim 1, wherein the sulfur content of component (C) is 0.3 to 5.0% by weight.

11. An adhesive using the acrylic adhesive composition according to claim 1.

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