JPH0488065A - Resin composition for primer - Google Patents

Abstract

PURPOSE:To obtain the subject composition having excellent adhesiveness to metals, free from generation of blister and effective in preventing the oxidation between a substrate metal plate and the primer layer caused by the impregnation of water by adding a specific curing agent to a composition composed of a specific epoxy acrylate resin and acrylic acid. CONSTITUTION:The objective composition free from generation of blister even after immersion in hot water for 1,000hr is produced by compounding (A) 100 pts.wt. of an epoxy acrylate resin produced by reacting a bisphenol A and/or bisphenol F epoxy resin having >=2 epoxy groups in one molecule with methacrylic acid and (B) 0.01-10 pts.wt. of acrylic acid and compounding the obtained resin composition with (C) a hydroperoxide of formula (R1 is 1-10C alkyl, cyclohexane, phenyl, etc.) and/or R2-OOH (R2 is H or 1-10C alkyl) and (D) an organic cobalt salt.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a resin composition for a primer used for lining metals such as iron, stainless steel, and aluminum, concrete, and the like.

[Conventional technology]

Since epoxy acrylate resin has excellent corrosion resistance, it is widely used for lining metals such as iron, stainless steel, and aluminum, concrete, and the like.

When lining the base material with a hair poxy acrylate resin, the base material is surface-treated by sandblasting or the like in advance, and a primer resin is applied.

After that, either unsaturated polyester resin or epoxy acrylate resin impregnated into glass fiber is used as a lining to form a corrosion-resistant layer, or unsaturated polyester resin mixed with glass flakes, etc., or epoxy acrylate-1 resin is used as a lining. A corrosion-resistant layer is applied by spraying.

When lining the above, if a corrosion-resistant layer is formed from epoxy acrylate resin or unsaturated polyester resin without applying a primer resin to the base material, the adhesiveness with the base material is poor, so chemical liquid or thermal shock Peeling occurs between the base material and the corrosion-resistant layer.

In order to prevent the above peeling, an epoxy resin, urethane resin, or epoxy acrylate resin primer is usually applied.

Epoxy resin primers have excellent adhesion to metals, but the epoxy acrylate resin or unsaturated polyester resin at the interface where it comes into contact with the epoxy resin may become uncured due to the effect of the epoxy resin curing agent. It has the disadvantage of being easy to use.

Urethane resin-based primers have good compatibility with epoxy acrylate resins or unsaturated polyester resins, but in hot and humid work sites, the curing speed increases, which causes operational inconvenience.

Moreover, when immersed in hot water, peeling (blister) between the base material and the corrosion-resistant layer is likely to occur.

For these reasons, when an unsaturated polyester resin or an epoxy acrylate resin is used as a corrosion-resistant layer in the lining, an epoxy acrylate resin primer is usually used.

Epoxy acrylate resin-based primers are usually cured with a combination of methyl ethyl ketone peroxide and an organic metal salt.

However, in this curing system, an uncured resin layer is generated under the influence of oxygen in the air, and therefore, the performance required as a primer cannot be fully brought out. In such a case,
It has the disadvantage that the adhesion with the base material decreases, and in systems where hot water etc. are present, water penetrates between the base material and the primer, making it easy for blisters to occur.

In addition, conventional epoxy acrylate resin-based primers have lower adhesion to metal than epoxy resin-based primers,
Blisters are likely to occur when immersed in hot water, and if the base material is iron, black rust is likely to occur due to water penetration.

[Problem to be solved by the invention]

The present invention solves the above problems and provides a primer that is not easily affected by oxygen in the air during curing, has good adhesion to metals, and generates little or no blisters when immersed in hot water. The present invention provides a resin composition for

[Means to solve the problem]

As a result of extensive studies, the present inventors have completed the present invention by using a specific curing agent in a composition consisting of a specific epoxy acrylate resin and acrylic acid.

That is, the present invention provides an epoxy resin comprising an epoxy acrylate obtained by reacting a bisphenol A type and/or bisphenol F type epoxy resin having at least two epoxy groups in one molecule with methacrylic acid and a vinyl monomer. A resin composition (C) consisting of 100 parts by weight of acrylate resin (A) and 0.01 to 10 parts by weight of acrylic acid (B) is added as a curing agent to a resin composition represented by the following formula (I) and/or (II). Brimer resin composition CH3 R+ COOH (I) CH3 (R1 in (■) is an alkyl having 1 to 10 carbon atoms) group, cyclohexyl group, substituted cyclohexyl group, phenyl group, or substituted phenyl group) R2-00H(II) ((■) in the formula, R2 is Hl or an alkyl group having 1 to 10 carbon atoms) be.

The epoxy acrylate used in the present invention is obtained from an epoxy resin and methacrylic acid by a known esterification reaction.

The epoxy resin used is an epoxy resin with an epoxy equivalent of 170 to 2000 obtained by reacting bisphenol A or bisphenol F with epichlorohydrin, or a carboxyl group-terminated butadiene/butadiene resin to further improve adhesion and rust prevention hardening. These are carboxyl-terminated butadiene/acrylonitrile copolymer-modified epoxy resins with an epoxy equivalent weight of 200 to 5,000 obtained by a reaction using an epoxy resin added with an acrylonitrile copolymer, and these can be used alone or in combination of two or more types of epoxy resins. It can be used as

As catalysts used in the esterification reaction described in Section 2, compounds having tertiary nitrogen such as triethylamine and imidazole derivatives, which are exemplified in Japanese Patent Publication No. 45-40069, etc.
Phosphorous compounds such as trimethylphosphine or amine salts such as tetramethylammonium chloride and triethylamine hydrochloride are used.

Epoxy acrylate synthesized by the above method is usually dissolved in vinyl monomer to form an epoxy acrylate resin (
It is used as A).

Vinyl monomers used in the present invention include styrene,
(Meth)acrylic esters such as chlorostyrene, divinylpentene or methyl (meth)acrylate, polyfunctional (meth)acrylic esters such as ethylene glycol di(meth)acrylate, etc. are used. These can be used alone or in combination of two or more.

The amount of the polymerizable vinyl monomer is practically 10 to 150 parts by weight per 100 parts by weight of epoxy acrylate.

An optimal cured product can be obtained at the above blending ratio.

In the present invention, acrylic acid (B) is blended in a proportion of 0.01 to 10 parts by weight per 100 parts by weight of epoxy acrylate resin (A).

If the blending ratio of acrylic acid (B) is below the range specified in ``2'', the adhesion to metals will decrease, and if it is above the range specified in ``2'', the hot water resistance will decrease, causing blistering.

The resin composition for a primer of the present invention has the general formula (I) and/or (II) added to the resin composition (C) of the present invention as a curing agent.
) Hydroperoxide (D) and organic cobalt salt (
E) can be mixed and cured at a curing temperature of 10 to 60°C, preferably -10 to 40°C.

As the hydroperoxide (D) used in the present invention, those represented by formulas (I) and/or (II) are used, such as hydrogen peroxide, t-butylhy]-roba-oxide, and cumene hydroperoxide. , diisopropylbenzene hydroperoxide, P-menthane hydroperoxide, 2,5-dimethylhexane-2,5-cybidrobar oxide, 1. , l, 33-tetramethylbutyl hydroperoxide and the like.

These can be used alone or in combination of two or more.

Further, hydroperoxide (D) can be used after being dissolved in water, a plasticizer, dimethyl fumarate, etc. in order to improve the solubility in the resin.

Hydroberoxide (D) is resin composition (C) 100
0.01 to 10 parts by weight, preferably 0.01 to 10 parts by weight.
It is used in a proportion of 5 to 5 parts by weight.

Considering the adjustment of the curing speed and the physical properties of the cured product, the above blending ratio is preferable.

As the organic cobalt salt (E) used in combination at this time, organic cobalt salts such as cobalt naphthenate and cobalt octenoate are used.

The amount of organic cobalt salt (E) added is determined by the amount of organic cobalt salt (E) added to the resin composition (C)
The amount is 0.01 to 10 parts by weight, preferably 0.1 to 3 parts by weight, per 100 parts by weight.

In consideration of workability and physical properties of the cured product, the above blending ratio is preferable.

In the present invention, corrosion resistance and adhesiveness can be improved by adding a filler to the resin composition (C) as needed.

As fillers used in the present invention, talc, whiskers,
Examples include mica and red iron.

These can ensure an appropriate coating thickness, improve adhesion, or provide rust prevention when applied to an iron plate, so they can be used alone or in combination of two or more.

When a filler is blended in the present invention, the blending ratio of the filler is 5 to 20 parts by weight based on 100 parts by weight of the resin composition (C).
0 parts by weight, preferably 5 to 150 parts by weight.

Considering the working viscosity and corrosion resistance during curing, the above blending ratio is preferable.

The present invention will be explained below with reference to Examples.

〔Example〕

The evaluation methods adopted in the present examples and comparative examples are as follows.

(1) Measurement of tensile shear strength Steel plate (material: 150 x 25 x thickness 3 (mm))
5S41) was subjected to Sun I blasting using a #70 grid, immediately degreased with acetone, and then dried with a hair dryer.

Primer resin was applied up to 25mm from the tip of the iron plate surface that had undergone the above treatment, and after curing at room temperature for 24 hours,
After further curing at 80°C for 2 hours, test pieces for tensile shear tests were prepared.

The measurement was performed under the condition that the tensile speed was 1 mm/min.

The adhesive strength was the value obtained by dividing the maximum breaking load by the adhesive area.

(2) Evaluation of hot water resistance by single-sided hot water immersion 200x20
Iron plate with dimensions of 0 x thickness 5 (mm) (material: 5S41)
Sandblast one side of with #70 grid,
After quickly degreasing with acetone, it was dried with a hair dryer.

A primer resin was applied to the above-treated iron plate surface, and the primer resin was left in a constant temperature room at 25° C. for 24 hours to harden.

To evaluate hot water resistance by immersing one side in hot water, the primer-coated surface was immersed in hot water at 96 to 98°C, and the primer-coated interface was observed every time the sample was immersed for a predetermined period of time.

Example 1 Bisphenol A type epoxy resin (Japan Chihagaiki Co., Ltd., trade name: Araldite #260) was placed in a four-eye flask equipped with a stirrer, an air inlet tube, a thermometer, and a condenser.
ooog, methacrylic acid 455g, hydroquinone 0
．． 58g, tetramethylammonium chloride 2.9
1 g of styrene and 623 g of styrene were charged and reacted at 120° C. for 2.5 hours while being careful not to generate heat, to obtain an epoxy acrylate resin with an acid value of 7.

To the above epoxy acrylate resin, 347 g of styrene,
72.8 g of acrylic acid was added, and the resin composition ((, -1,
) was obtained.

Next, to 100 parts by weight of the resin composition ((, -1,), 1.0 parts by weight of 80% cumene hydroperoxide (manufactured by Kayaku Akzo (M, trade name: Kayakumen H)) and 6% 0.5 parts by weight of cobalt naphthenate (Nippon Kagaku Sangyo Co., Ltd. (stock company, trade name, cobalt naphthenate)) was blended to obtain a resin composition for primer (a).

The tensile shear strength and hot water resistance by single-sided hot water immersion were evaluated using the primer resin composition (a) described in ``2''.

The evaluation results are shown in Tables 1 and 2.

Example 2 A bisphenol A type epoxy resin modified with carboxyl group-terminated butadiene/acrylonitrile copolymer (Dainippon Ink & Chemicals Co., Ltd. Name: Epicron TSR601) looOg, methacrylic acid 187
g 0.47 g of hydroquinone, 2.37 g of tetramethylammonium chloride, and 600 g of styrene were charged and reacted at 120° C. for 3.5 hours while being careful not to generate heat, to obtain an epoxy acrylate resin with an acid value of 5.

371 g of styrene and 21.6 g of acrylic acid were added to the resin obtained in the above reaction to obtain a resin composition (C-2).

Next, the same curing agent used in Example 1 was added to the resin composition (C-2) in the same proportion to obtain a resin composition for a primer (b).

The tensile shear strength and hot water resistance by single-sided hot water immersion were evaluated using the resin composition (b) for primers.

The evaluation results are shown in Tables 1 and 2.

Example 3 Resin composition (C1) used in Example 1
In addition, as a filler, 15g of red iron and 50g of talc.
was added and sufficiently stirred to obtain a resin composition (C-3).

Next, 1.0 parts by weight of t-butyl hydroperoxide (manufactured by NOF ■, trade name: Perbutyl H) as a curing agent and 6% cobalt naphthenate (
Manufactured by Nippon Kagaku Sangyo ■, product name: Naftex Cobalt)
0. A resin composition for primer (
c) was obtained.

Using the resin composition (c) for primers, tensile shear strength and hot water resistance were evaluated by immersion in hot water on one side.

The evaluation results are shown in Tables 1 and 2.

Comparative Example I Bisphenol A type epoxy resin (manufactured by Nippon Chiba Kaikyo, trade name: Araldite #260) 1 was placed in a four-eye flask equipped with a stirrer, air inlet tube, thermometer, and condenser.
000g, methacrylic acid 455g, hydroquinone 0.
58g.

2.91 g of tetramethylammonium chloride and 623 g of styrene were charged and reacted at 120° C. for 2.5 hours while being careful not to generate heat, to obtain an epoxy acrylate resin with an acid value of 6.

347 g of styrene was added to the resin obtained in the above reaction to obtain a resin composition (C-4).

8 as a curing agent to 1.00 parts by weight of the resin composition (C-4)
Made of 0% cumene hydroperoxide (Kayaku Akzo@),
1.0 parts by weight of product name: Kayakumen H) and 0.5 parts by weight of 6% cobalt naphthenate (manufactured by Nippon Kagaku Sangyo ■, product name: Naftex Cobalt) were blended to obtain a resin composition for primer (d). Ta.

Using the resin composition (d) for primers, tensile shear strength and hot water resistance were evaluated by dipping one side in hot water.

The evaluation results are shown in Tables 1 and 2.

Comparative Example 2 Resin composition (C4) prepared in Comparative Example 1 1.00
Add 55% methyl ethyl ketone peroxide (manufactured by Nippon Oil & Fats ■, trade name, Permec N) as a curing agent to parts by weight.1.
0 parts by weight, and 0.5 parts by weight of 6% cobalt naphthenate (manufactured by Nippon Kagaku Sangyo@, trade name: Naftex Cobalt) to obtain a resin composition for primer (e).

The tensile shear strength and hot water resistance by single-sided hot water immersion were evaluated using the resin composition (e) for primers.

The evaluation results are shown in Tables 1 and 2.

Comparative Example 3 Epoxy acrylate resin commonly used for corrosion resistance (manufactured by Nippon U-Pica, trade name: Neopol 8250L)
) was used as the resin composition (C-5).

As a curing agent, 55% methyl ethyl ketone peroxide (NOF Co., Ltd.) was added to 100 parts by weight of the resin composition (C-5).
Stock system, product name: Permec N) 1.0 parts by weight, and 6%
0.5 parts by weight of cobalt naphthenate (manufactured by Nippon Kagaku Sangyo@, trade name: Naftex Cobalt) was blended to obtain a resin composition for a primer.

The tensile shear strength and hot water resistance by single-sided hot water immersion were evaluated using the primer composition resin (2).

The evaluation results are shown in Tables 1 and 2.

Comparative Example 4 A commercially available epoxy acrylate resin for primers that has excellent adhesion to metals (Japan U-Pica Co., Ltd.,
(trade name: Neopol 8350H) was used as the resin composition (C-6) in the present invention.

As a curing agent, for 100 parts by weight of the resin composition ((,-6), 1.0 parts by weight of 55% methyl ethyl ketone peroxide (manufactured by NOF ■, trade name: Permec N) and 6% cobalt naphthenate (Japan 0.5 parts by weight of Naftex Cobalt (trade name, manufactured by Kagaku Sangyo@) was blended to obtain a primer resin composition (g).

The tensile shear strength and hot water resistance by single-sided hot water immersion were evaluated using the resin composition (g) for primers.

The evaluation results are shown in Tables 1 and 2.

Table 1, Tensile shear strength measurement results Table 2 Single-sided immersion test results [Effects of the present invention] From the results in Tables 1 and 2, the resin composition for primers of the present invention is more effective than ordinary epoxy acrylate resins. It has excellent adhesion to metals, and no blisters appear even after being immersed in hot water for 1000 hours. Furthermore, it can be seen that oxidation at the interface between the base steel sheet and the primer due to water penetration is less likely to occur at the primer application interface after immersion in hot water, compared to conventional epoxy acrylate resin primers.

Patent applicant: Nippon U-Pica Co., Ltd. Agent: Patent Attorney Sadafumi Kohori

Claims (3)

[Claims] (1) An epoxy acrylate resin consisting of an epoxy acrylate obtained by reacting a bisphenol A type and/or bisphenol F type epoxy resin having at least two epoxy groups in one molecule with methacrylic acid and a vinyl monomer ( A) 100 parts by weight and acrylic acid (B) 0
．． A hydroperoxide (D) represented by the following general formula (I) and/or (II) as a curing agent and an organic cobalt salt (
A resin composition for a primer containing E). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (R_1 in (I) is an alkyl group having 1 to 10 carbon atoms,
A cyclohexyl group, a substituted cyclohexyl group, a phenyl group, or a substituted phenyl group. ) R_2-OOH(II) (R_2 in formula (II) is H or an alkyl group having 1 to 10 carbon atoms.) (2) The epoxy resin used is an epoxy resin modified with a carboxyl group-terminated butadiene/acrylonitrile copolymer, or an epoxy resin mixture containing the modified epoxy resin. Resin composition for primer. (3) The resin composition for a primer according to claim (1), wherein 5 to 200 parts by weight of at least one of talc, whisker, mica, or red iron is blended as a filler with respect to 100 parts by weight of the resin composition (C).