JPH09132760A - Two-component base type acrylic adhesive - Google Patents

Abstract

(57) [Summary] [Objective] To provide a two-pack type acrylic adhesive having a high curing speed and good storage stability. [Structure] 100 parts by weight of a polymerizable (meth) acrylic monomer, 1 to 10 parts by weight of an organic peroxide, and 0.01 to 5 parts by weight of an acidic phosphate ester as an essential component A agent, and a polymerizable (meth) ) A two-component base type acrylic adhesive composed of agent B containing 100 parts by weight of an acrylic monomer, 0.1 to 10 parts by weight of a vanadium compound, and 0.1 to 20 parts by weight of an acidic phosphate ester as an essential component A two-component main agent type acrylic adhesive, wherein the agent and / or the agent B contains 0.1 part by weight or more of alcohol.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acrylic adhesive, and more specifically, it is a two-component base type acrylic resin which has a high curing rate, eliminates tackiness on the air contact surface in a short time, and has good storage stability. System adhesive.

[0002]

2. Description of the Related Art (Meth) acrylic monomers (in the present invention, (meth) acrylic represents acrylic or methacrylic. ], A two-component type acrylic adhesive containing an organic peroxide and a reducing agent that forms a redox catalyst system with the organic peroxide is cured at room temperature in a short time and is stoichiometric. It has the feature that it does not require strict metering and mixing of the two liquids in the sense, and that it is easy to handle. Also, in recent years, the adhesive strength characteristics such as tensile strength, impact strength, and peel strength have been greatly improved, and the initial type is called a first-generation acrylic adhesive (FGA), while the recent adhesive strength characteristics have been improved. Is called a second generation acrylic adhesive (SGA) to distinguish them. Furthermore, if classified according to the difference in composition and workability, there are a two-liquid main agent type and a primer type (also referred to as a main agent-primer type) (Haraga et al,
Japan Adhesive Association magazine 24 No.12), the two-component main agent type contains both (A) and (B) as a main component of (meth) acrylic monomer, and each has a property of giving a cured product by redox polymerization. There is. In the primer type, one of the two liquids is a curing accelerator solution, which plays a role of curing the main agent containing a (meth) acrylic monomer as a main component by redox polymerization, but does not itself cure. In terms of workability, for example, in the case of the two-liquid main agent type, the two liquids are mixed and applied immediately before use, or the agent A is applied to one of the adherends and the agent B is applied to the other to rub them together. The method of pasting is adopted. On the other hand, in the primer type, one of the adherends is coated with the primer as thinly as possible, the other is coated with the main component, and then the two are rubbed together to be bonded. Examples of the two-component base agent type are JP-A-53-2543, and examples of the primer type are JP-A-51-7040 and JP-B-53-24103.
And the like.

A description of an adhesive which uses a redox catalyst system composed of an organic peroxide and a soluble vanadium compound as a redox catalyst system is described in JP-B-49-2.
There are many such as 1093. Furthermore, a redox catalyst system consisting of an organic peroxide, a vanadium compound, and an acidic phosphoric acid ester is a curing agent system (LH
ALLAN, Plastics, June p 250-253, 1960) and JP-A-48
No. 21775 and the like. In addition, an example of using an acidic phosphate ester with a specific structure for an acrylic adhesive is
JP-A-51-132234, JP-A-58-14747
No. 7, etc. In addition, the present inventors disclosed in JP-A-5-125331 that a polymerizable (meth) acrylic monomer, an organic peroxide, an agent A composed of phosphorous acid and / or a specific acidic phosphorus compound, and a polymerizable (meth) ) Disclosed is a two-component base type acrylic adhesive composed of an acrylic monomer, an organic peroxide in the agent A, and an agent B having a soluble vanadium compound forming a Redox catalyst system as a main component.

Adhesives using a redox catalyst system composed of these organic peroxides, vanadium compounds, and phosphorus compounds are characterized by a faster curing rate than conventional adhesives, but depending on the application. Further improvement in curing rate is desired. In order to increase the curing speed, increasing the compounding amount of the catalyst system is generally used, but in this case, it has a drawback that the storage stability of the adhesive is lowered.

[0005]

As described above, the two-pack type acrylic adhesive is evaluated in the fields of electric machinery, machinery, construction, etc., because of its advantages of easy handling and excellent adhesive strength characteristics. Is often used in. The present invention, while maintaining the advantages of such a two-component acrylic adhesive,
It is an object of the present invention to provide a two-component acrylic adhesive whose curing rate is increased without impairing storage stability.

[0006]

[Means for Solving the Problems] The inventors of the present invention have conducted extensive research to solve the above problems. As a result, 100 parts by weight of the polymerizable (meth) acrylic monomer, 1 to 10 parts by weight of the organic peroxide, 0.01 to 5 parts by weight of the acidic phosphate ester as an essential component A agent, and the polymerizable (meth ) 100 parts by weight of acrylic monomer, 0.1 vanadium compound
-10 parts by weight, agent A of a two-component base type acrylic adhesive composed of agent B containing 0.1 to 20 parts by weight of acidic phosphoric acid ester as an essential component, and / or agent B with alcohol of 0. It was found that the two-component base type acrylic adhesive contained in an amount of 1 part by weight or more has a high curing speed and good storage stability, and the amount of the above-mentioned alcohol is 100 parts by weight of the polymerizable (meth) acrylic monomer. 0.1 to 3 for each part
The inventors have found that when the amount is 0 parts by weight, the solubility in other components of alcohol is good and the production can be easily performed, and the present invention has been completed.

Hereinafter, the present invention will be described in more detail. Polymerizability (meta) used in both A agent and B agent in the present invention
As the acrylic monomer, (meth) acrylic acid,
(Meth) acrylic acid alkyl ester, phenoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, (meth) acrylic acid hydroxyalkyl ester,
Poly (meth) acrylate of polyhydric alcohol, epoxy (meth) acrylate obtained by addition reaction of (meth) acrylic acid with epoxy resin, urethane poly (meth) acrylate, polyester (meth) acrylate, or 2,2- Examples include di (meth) acrylates of alkylene oxide adducts of bisphenol A or bisphenol S such as bis [4- (methacryloxyethoxy) phenyl] propane, which may be used alone or 2
Used in combination of more than one species.

As the organic peroxide to be blended in the agent A, hydroperoxides such as t-butyl hydroperoxide, p-menthane hydroperoxide, cumene hydroperoxide and diisopropylbenzene hydroperoxide, t-butyl peroxylaurate, t-butyl peroxybenzoate, t
-Peroxyesters such as butyl peroxide decanoate can be used alone or in combination of two or more, but from the viewpoint of curing in a short time which is one of the features of the present invention, hydroperoxides Is particularly preferable. The blending amount of the organic peroxide is 1 to 100 parts by weight of the polymerizable (meth) acrylic monomer blended in the agent A.
It is preferably 10 parts by weight, and more preferably 2 to 5 parts by weight. If the compounding amount of the organic peroxide is less than 1 part by weight, the curing rate is lowered, which is not preferable, and conversely, if it exceeds 10 parts by weight, the storage stability of the adhesive is deteriorated, which is not preferable.

Further, as the acidic phosphoric acid ester to be blended with the A and B agents of the two-component base type acrylic adhesive of the present invention, monomethyl phosphate, dimethyl phosphate, monoethyl phosphate, diethyl phosphate, and monophosphate are used. Butyl phosphate, dibutyl phosphate, mono-β-chloroethyl phosphate, di-β-
Chloroethyl Phosphate, Monoethoxyethyl Phosphate, Diethoxyethyl Phosphate, Phenyl Phosphate, Diphenyl Phosphate, Mono (meth) acryloyloxyethyl Phosphate, Di (meth) acryloyloxyethyl Phosphate, Mono (meth) acryloyl Examples thereof include oxypropyl phosphate, di (meth) acryloyloxypropyl phosphate, polypropylene glycol mono (meth) acrylate phosphate and the like, and these may be used alone or in combination of two or more kinds.

The above-mentioned acidic phosphate ester acts as a storage stabilizer in the agent A with a small blending amount. If the blending amount is too large, the decomposition of the organic peroxide contained in the agent A is likely to proceed, and the curing rate tends to decrease during use. On the other hand, with agent B, when used,
It acts as an auxiliary agent of a redox catalyst composed of an organic peroxide and a vanadium compound, accelerates curing of the adhesive, and also acts as a storage stabilizer for the agent B. In addition, in order to further increase the curing rate in the agent B, it is possible to add an acidic phosphate ester in a larger amount than in the agent A. From this point of view, the compounding amount of the acidic phosphoric acid ester is preferably 0.01 to 5 parts by weight, and more preferably 0.05 to 5 parts by weight with respect to 100 parts by weight of the polymerizable (meth) acrylic monomer to be compounded in the agent A. 2 parts by weight is more preferred. On the other hand, in the agent B, 0.1 to 20 parts by weight is preferable, and further 0.5 to 10 parts by weight is more preferable, relative to 100 parts by weight of the polymerizable (meth) acrylic monomer blended.

Examples of the vanadium compound blended in the agent B include vanadyl acetylacetonate, vanadyl stearate, vanadium naphthenate, vanadium acetylacetonate, vanadium benzoylacetonate, etc., which may be used alone or Two or more kinds are used in combination. The vanadium compound content is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the polymerizable (meth) acrylic monomer contained in the agent B,
Furthermore, 1 to 5 parts by weight is more preferable. If the blending amount of the vanadium compound is less than 0.1 parts by weight, the curing rate is slow, which is not preferable. Conversely, if it exceeds 10 parts by weight, not only the curing rate proportional to the blending amount will not be improved, but also
It is not preferable because the storage stability is lowered.

On the other hand, alcohols to be mixed in the agent A and / or the agent B are methanol, ethanol, n-
Propyl alcohol, isopropyl alcohol, monohydric alcohol such as n-butyl alcohol, ethylene glycol, propylene glycol, 1,2-butanediol,
1,3-butanediol, 1,4-butanediol,
Dihydric alcohols such as 2,3-butanediol, diethylene glycol and dipropylene glycol, and polyhydric alcohols such as glycerin, diglycerin, polyglycerin, trimethylolpropane, pentaerythritol, and sorbitol, and the like, and these alone, Alternatively,
Used in combination of two or more. The amount of alcohol is the same for both A agent and B agent.
Polymerizable (meth) acrylic monomer 1 blended in the agent
It is 0.1 part by weight or more, more preferably 0.5 part by weight or more, relative to 00 parts by weight. If the amount of alcohol is less than 0.1 part by weight, the curing rate is not significantly improved, which is not preferable. The upper limit of the amount of alcohol to be blended is not particularly limited, but from the viewpoint of ensuring sufficient solubility in other components and facilitating the production, 100 parts by weight of the polymerizable (meth) acrylic monomer is added. On the other hand, it is desirable to set it to 30 parts by weight or less.

In addition, in the present invention, polymethyl methacrylate, polyvinyl butyral, and acrylonitrile-styrene copolymer are added to the agent A and / or the agent B for the purpose of adjusting viscosity and improving flexibility of the cured product. (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), methacrylic acid ester-
Thermoplastic resins such as butadiene-styrene copolymer (MBS resin), methacrylic acid ester-butadiene-acrylonitrile-styrene copolymer (MBAS resin), styrene-butadiene rubber (SBR), polybutadiene rubber (BR), polyisoprene rubber (IR), chloroprene rubber (CR), nitrile rubber (NBR), chlorinated rubber, acrylic rubber, epichlorohydrin rubber and other rubbers, liquid polybutadiene, terminal acrylic modified liquid polybutadiene,
Liquid rubber such as liquid acrylonitrile-butadiene copolymer, fine powder polyethylene for the purpose of imparting thixotropy, dibenzylidene-D-sorbitol, cellulose triacetate, stearamide, bentonite,
A thixotropic agent such as finely powdered silicic acid, and 2,6-di-t-butyl-4- for the purpose of improving long-term storage stability at room temperature.
Methylphenol, 2,2-methylenebis (4-methyl-6-t-butylphenol), benzoquinone, hydroquinone, quinhydrone, ethylenediaminetetraacetic acid 4 sodium salt, oxalic acid, N-methyl-N-nitrosoaniline, N-nitrosodiphenylamine, etc. A radical polymerization inhibitor and a dye or pigment for coloring can be added.

Further, in the present invention, A
The viscosity of agents B and B can be flexibly set. That is,
In applications where the agents A and B are mixed and used at the time of use, the composition may be determined so that the agents A and B have almost the same viscosity. In addition, for example, one of the adherends is thinly applied with one liquid, the other adherend is applied with the other liquid, and then the both are adhered together, a so-called primer type described above. For the purpose of general use, for example, the composition may be determined so that the agent A has a high viscosity and the agent B has a low viscosity. For the viscosity adjustment, the above-mentioned thermoplastic resin, rubber, liquid rubber, thixotropic agent, etc. are preferably used.

[0015]

The curing speed of the two-component base type acrylic adhesive of the present invention is improved. It is speculated that this is because alcohol has some effect on the redox polymerization catalyst system composed of an organic peroxide, an acidic phosphoric acid ester, and a vanadium compound to accelerate the decomposition of the organic peroxide.

[0016]

The present invention will be described in more detail with reference to Examples and Comparative Examples. In the following Examples and Comparative Examples, parts represent parts by weight, and storage stability, set time, touch dry time, and adhesive strength (tensile shear strength, peel strength) were measured under the following conditions. I went. <Storage Stability> 80 g of each of the agents A and B is put in a 100 cc glass bottle, sealed, and stored in a dryer kept at 40 ° C., and the time until a gel is formed is measured. <Set time> In a constant temperature and humidity room of 23 ° C. and 50% RH, cold-rolled steel sheets having a shape of 1.6 × 25 × 100 mm are mixed by a 12 mm wrap with equal amounts of agent A and agent B and bonded,
The time until the peeling does not occur even when a load of 5 kgf is applied is measured. <Dry touch time> In a constant temperature and humidity room of 23 ° C. and 50% RH, equal amounts of agents A and B are dropped on a polyethylene film, and then mixed, and tackiness of the air contact surface of the mixture by touching the fingers. Measure the time until it disappears. <Adhesive strength> A in a constant temperature and humidity room at 23 ° C and 50% RH
Agent and B agent in equal amounts on one of the adherends, and then
The other adherend is rubbed together and fixed by adhesion, and after 24 hours, the following strengths are measured under the same conditions. [Tensile shear strength] A cold-rolled steel plate having a shape of 1.6 × 25 × 100 mm, an acrylic resin plate, and a plywood are adhered with a 12 mm wrap, and measured according to ASTM D 1002-64. [Peeling strength] A cold-rolled steel sheet having a shape of 0.6 × 25 × 200 mm was adhered and measured according to ASTM D1876-72.

[Examples 1 to 3] Using the common composition shown below and the three kinds of alcohols shown in Table 1, three kinds of agent A were prepared. Further, agent B was prepared with the composition shown below. When the storage stability at 40 ° C. of the obtained three kinds of agent A and agent B was evaluated, it was stable for 30 days or more.
Then, three kinds of agents A and B are mixed in equal amounts, and set time, touch dry time, and tensile shear strength are measured, and curing characteristics,
Also, the properties of the cured product were evaluated. Table 1 shows the results. Common composition of agent A 2-hydroxypropyl methacrylate 80 parts 2,2-bis [4- (methacryloxyethoxy) phenyl] propane 20 parts monobutyl phosphate 0.5 parts p-benzoquinone 0.1 part MBS resin ¹⁾ 65 Part Cumene hydroperoxide 6 parts Alcohol having one or more hydroxyl groups in the molecule 0.02 mol (however, n-butanol ... 1.48 parts, 1,3-butanediol ... 1.8 parts 1,4-butanediol (1.8 parts) Composition of agent B 2-hydroxypropyl methacrylate 80 parts 2,2-bis [4- (methacryloxyethoxy) phenyl] propane 20 parts Monobutyl phosphate 4.5 parts Hydroquinone 0.2 parts MBS resin ¹⁾ 65 parts vanadyl acetylacetonate 0.5 part ¹⁾ "JSR MBS61" manufactured by Nippon Synthetic Rubber Co., Ltd.

Comparative Example 1 Agent A was prepared in the same manner as in Examples 1 to 3 except that the agent A was not blended with alcohol. The agent A thus obtained was stable at 40 ° C. for 30 days or longer. Next, this agent A and the same agent B prepared in Examples 1 to 3 were mixed in equal amounts, and the set time, the touch dry time and the tensile shear strength were measured. The results are shown in Table 1 together with the results of Examples 1 to 3.

[0019]

[Table 1]

From Table 1, Example 1 using alcohol
In comparison with Comparative Example 1 in which alcohol is not used,
It can be seen that the set time is shortened, and the dry time to the touch is not adversely affected.

Examples 4 to 7 and Comparative Example 2 Agent A was prepared with the composition shown below. Furthermore, the B composition was prepared using the common composition shown below and 1,4-butanediol as the alcohol in the amounts shown in Table 2. Obtained agent A and B
When the storage stability of the agent at 40 ° C. was evaluated, it was stable for 30 days or more. Further, the agents A and B were mixed in equal amounts, and set time, tensile shear strength, and peel strength were measured. Table 2 shows the results. Composition of agent A Methyl methacrylate 50 parts 2-Hydroxyethyl methacrylate 40 parts 2,2-Bis [4- (methacryloxyethoxy) phenyl] propane 10 parts Nitrile rubber ²⁾ 20 parts Monomethacryloyloxyethyl phosphate ³⁾ 0.1 Part quinhydrone 0.1 part cumene hydroperoxide 4 parts common composition of agent B methyl methacrylate 50 parts 2-hydroxyethyl methacrylate 40 parts 2,2-bis [4- (methacryloxyethoxy) phenyl] propane 10 parts nitrile rubber ²⁾ 20 parts Monomethacryloyloxyethyl phosphate ³⁾ 3 parts Hydroquinone 0.1 part Vanadyl acetylacetonate 0.5 part 1,4-butanediol ²⁾ Nipon 1072J manufactured by Zeon Corporation ³⁾ Kyoeisha Made by Kagaku Co., Ltd. PM "

[Comparative Example 3] Agent B was prepared in the same manner as in Examples 4 to 7, except that agent B was not blended with 1,4 butanediol. The obtained agent B was stable at 40 ° C. for 30 days or longer. Next, this agent B and the same agent A prepared in Examples 4 to 6 were mixed in equal amounts, and the set time, peel strength and tensile shear strength were measured. The results are shown in Table 2 together with the results of Examples 4 to 7.

[0023]

[Table 2]

From Table 2, Examples 4-7 using 1,4-butanediol in an amount in the range disclosed in this invention.
Shows that the set time and the touch dry time are shortened as compared with Comparative Example 2 in which the amount used is less than the amount disclosed in the present invention and Comparative Example 3 in which alcohol is not used at all.

[0025]

As described above, according to the present invention, there is provided a two-component acrylic adhesive which has a high curing rate and good storage stability. The two-component acrylic adhesive has an improved curing speed while keeping the advantages of the conventional two-component acrylic adhesives being easy to handle and having excellent adhesive strength characteristics. Was done,
It also has excellent storage stability. Therefore, the two-pack type acrylic adhesive can be suitably used in a wide range of fields such as electric machines, machines, and construction.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Matsuda ▲ Hide ▼ Akira 1515 Nakatsu-cho, Marugame-shi, Kagawa Inside Okura Industrial Co., Ltd.

Claims (2)

[Claims] 1. A polymerizable (meth) acrylic monomer 10
0 parts by weight, 1 to 10 parts by weight of organic peroxide, 0.01 to 5 parts by weight of acid phosphate ester as an essential component A, and 100 parts by weight of a polymerizable (meth) acrylic monomer.
Agent A and / or agent B in a two-component base type acrylic adhesive composed of agent B containing 0.1 to 10 parts by weight of vanadium compound and 0.1 to 20 parts by weight of acidic phosphate ester as essential components A two-component base type acrylic adhesive characterized in that the alcohol contains 0.1 part by weight or more. 2. The two-component, main-agent-type acrylic resin according to claim 1, wherein the amount of alcohol is 0.1 to 30 parts by weight with respect to 100 parts by weight of the polymerizable (meth) acrylic monomer. adhesive.