JP2001163955A - Epoxy resin curing agent and composition - Google Patents

Abstract

[PROBLEMS] To use bis (aminomethyl) cyclohexane as a raw material, to prevent the cured epoxy resin coating from being sticky, to prevent whitening caused when water drops are dropped on the coating, and to improve storage stability. Provides an excellent epoxy resin curing agent. A polyamine compound (A) containing bis (aminomethyl) cyclohexane or a modified product thereof, a fatty amine compound (B) containing a component having an alkyl group having 12 carbon atoms or an iodine value of 50 or more, and curing An epoxy resin curing agent comprising an accelerator (C).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin curing agent useful as a coating material used for anticorrosion of paints, flooring materials, metals and concretes, and an epoxy resin comprising the epoxy resin curing agent and an epoxy resin. It relates to a resin composition.

[0002]

2. Description of the Related Art Conventionally, various polyamine compounds are widely known as epoxy resin curing agents. In particular, aliphatic polyamine compounds are widely used as epoxy resin curing agents for room temperature curing, such as room temperature curing type epoxy resins and epoxy resin curing agents, paints,
There are flooring materials. Among the aliphatic polyamines, bis (aminomethyl) cyclohexane is superior to other aliphatic polyamines in terms of low-temperature curability, and provides a cured product having excellent chemical resistance and weather resistance.

[0003] However, bis (aminomethyl) cyclohexane absorbs carbon dioxide in the atmosphere to form carbamate, and since this carbamate is hygroscopic,
When used as an epoxy resin curing agent, the cured epoxy resin coating has a disadvantage that the coating becomes sticky and the appearance of the coating deteriorates. Further, there is a phenomenon that when a water drop is dropped on the cured epoxy resin coating film, the portion becomes white. Therefore, bis (aminomethyl) cyclohexane is unmodified and is rarely used as an epoxy resin curing agent, but is used as various modified products. However, the disadvantages of bis (aminomethyl) cyclohexane have not been sufficiently solved.

JP-A-8-3282 discloses an epoxy resin curing agent comprising a polyamine compound containing bis (aminomethyl) cyclohexane or a modified product thereof and an alkylamine compound having 16 to 18 carbon atoms. I have. By using this, the adhesive state of the surface of the cured epoxy resin coating film can be eliminated, and changes such as whitening caused when water droplets are dropped on the coating film can be prevented, but the epoxy resin curing agent separates the alkylamine during storage. Storage stability is poor, such as dripping, precipitation of crystals, and solidification of the entire epoxy resin curing agent.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to use bis (aminomethyl) cyclohexane as a raw material, to prevent the cured epoxy resin coating film from being sticky and to prevent whitening caused when water drops are dropped on the coating film. Another object of the present invention is to provide an epoxy resin curing agent having excellent storage stability.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies on an epoxy resin curing agent having bis (aminomethyl) cyclohexane as a raw material having the above-mentioned problems, and as a result, have found that bis (aminomethyl) cyclohexane and bis (aminomethyl) cyclohexane by using the epoxy resin curing agent consisting of aminomethyl) cyclohexane modified product with a specific fatty amine compound and a curing accelerator, no stickiness and whitening, that epoxy resin composition having excellent storage stability can be obtained Found and arrived at the present invention.

That is, the present invention relates to a polyamine compound (A) containing bis (aminomethyl) cyclohexane and / or a modified product thereof, and a fat containing a component having an alkyl group having 12 carbon atoms or having an iodine value of 50 or more. An epoxy resin curing agent comprising an amine compound (B) and a curing accelerator (C), and an epoxy resin composition comprising the epoxy resin curing agent and an epoxy resin.

[0008]

DETAILED DESCRIPTION OF THE INVENTION As the bis (aminomethyl) cyclohexane used in the present invention, 1,3-bis (aminomethyl) cyclohexane is preferably used. The following method is used for the modification of bis (aminomethyl) cyclohexane. (1) Mannich reaction of bis (aminomethyl) cyclohexane with phenolic compounds and aldehyde compounds. (2) Reaction of bis (aminomethyl) cyclohexane with an epoxy compound. (3) Reaction of bis (aminomethyl) cyclohexane with a compound having a carboxyl group. (4) Michael reaction between bis (aminomethyl) cyclohexane and an acrylic compound.

Accordingly, the polyamine compound (A) in the present invention includes bis (aminomethyl) cyclohexane, a modified product of Bis (aminomethyl) cyclohexane with a phenolic compound and an aldehyde compound by a Mannich reaction, and bis (aminomethyl) cyclohexane. Modified product by reaction with epoxy compound, modified product by reaction of bis (aminomethyl) cyclohexane with compound having carboxyl group, or modified product by Michael reaction of acrylic compound of bis (aminomethyl) cyclohexane Only one kind may be used, and two or more kinds may be contained.

Bis (aminomethyl) used in the present invention
As a modified product of cyclohexane by a Mannich reaction of a phenol compound and an aldehyde compound, a reaction product of 1,3-bis (aminomethyl) cyclohexane with a phenol compound and an aldehyde compound is preferable. Examples of the phenolic compound used for this modification include phenol, cresol, butylphenol, and nonylphenol. Examples of the aldehyde compound include formaldehyde, acetaldehyde, and benzaldehyde. Generally, an aqueous formaldehyde solution is used. The reaction ratio of bis (aminomethyl) cyclohexane with the phenolic compound and the aldehyde compound during the modification is such that the gelation can be avoided and the obtained reaction product contains an amino group having active hydrogen. It is not particularly limited.

Bis (aminomethyl) used in the present invention
As a modified product of cyclohexane with an epoxy compound, 1,
A reaction product of 3-bis (aminomethyl) cyclohexane and an epoxy compound is preferred. Examples of the epoxy compound used for the modification include a monoepoxy compound such as butyl glycidyl ether and phenyl glycidyl ether and a diepoxy compound such as bisphenol A diglycidyl ether. The epoxy compound used for these modifications may be a single epoxy compound or a mixture of several epoxy compounds. The reaction ratio between bis (aminomethyl) cyclohexane and the epoxy compound at the time of modification is not particularly limited as long as gelation can be avoided and the obtained reaction product contains an amino group having active hydrogen. Not done.

Bis (aminomethyl) used in the present invention
As a modified product of cyclohexane and a compound having a carboxyl group, a reaction product of 1,3-bis (aminomethyl) cyclohexane and a compound having a carboxyl group is preferable. Examples of the compound having a carboxyl group used for the modification include polymerized fatty acids which are generally called dimer acids, dicarboxylic acids such as adipic acid and sebacic acid, and tall oil fatty acids, and monocarboxylic acids such as oleic acid and stearic acid. The reaction ratio between bis (aminomethyl) cyclohexane and the compound having a carboxyl group at the time of the modification is such that the gelation can be avoided and the obtained reaction product contains an amino group having active hydrogen. There is no particular limitation.

Bis (aminomethyl) used in the present invention
As a modified product by the Michael reaction of cyclohexane and an acrylic compound, a reaction product of 1,3-bis (aminomethyl) cyclohexane and a compound having a carbon-carbon double bond adjacent to a nitrile group or a carbonyl group is preferable. is there. Specific examples of acrylic compounds used for modification include acrylonitrile, methyl methacrylate, and the like. The reaction ratio between bis (aminomethyl) cyclohexane and the acrylic compound at the time of modification is not particularly limited as long as gelation can be avoided and the obtained reaction product contains an amino group having active hydrogen. Is not done.

The polyamine compound (A) used in the present invention contains polyamines other than the above-mentioned modified bis (aminomethyl) cyclohexane and bis (aminomethyl) cyclohexane, and modified polyamines. It may be. The content of these other polyamines and modified products of the polyamines is desirably an amount that does not impair the characteristics of bis (aminomethyl) cyclohexane or the effects of the present invention, and is 50% by weight or less of the entire polyamine compound. Desirably.

The epoxy resin curing agent of the present invention comprises a polyamine compound (A) containing a component having an alkyl group having 12 carbon atoms or a fatty amine compound (B) having an iodine value of 50 or more; It is characterized by containing a curing accelerator (C).

The fatty amine compound (B) used in the present invention is a primary amine, secondary amine or tertiary amine compound produced mainly from a fatty acid or a higher alcohol, and has 12 carbon atoms. A fatty amine compound containing 50% or more of a component having a group or a fatty amine compound having an iodine value of 50 or more is desirable, and a compound having a primary amine is particularly desirable.

Examples of the fatty amine compound containing 50% or more of the component having an alkyl group having 12 carbon atoms include compounds such as dodecylamine and cocoalkylamine. Examples of the fatty amine compound having an iodine value of 50 or more include compounds such as oleylamine and soybean alkylamine. By using such a fatty amine compound, excellent storage stability of the epoxy resin curing agent, elimination of stickiness of a coating film, and improvement of water resistance can be obtained.

The curing accelerator (C) in the present invention comprises 3
A normal epoxy resin curing accelerator such as a secondary amine, an acid, an alcohol, a phenol, and a phosphorus is used. In addition, the epoxy resin curing agent may contain a non-reactive diluent such as benzyl alcohol and a high-boiling hydrocarbon.

The composition ratio of the epoxy resin curing agent used in the present invention, that is, the compounding ratio of the polyamine compound (A), the fatty amine compound (B) and the curing accelerator (C) is 100% of the polyamine compound (A). It is preferable to contain 5 to 15 parts by weight of the fatty amine compound (B) and 3 to 10 parts by weight of the curing accelerator (C) based on parts by weight. If the blending ratio of the fatty amine compound (B) is less than 5 parts by weight, stickiness and water resistance of the coating film will be reduced, and if it exceeds 15 parts by weight, excellent storage stability cannot be obtained. On the other hand, if the proportion of the curing accelerator (C) is less than 3 parts by weight, the coating becomes sticky and the water resistance is reduced, and if it is more than 10 parts by weight, adverse effects on the properties of the coating are likely to occur.

The epoxy resin used in the epoxy resin composition of the present invention is desirably liquid at room temperature, and is typically a polymerization product of bisphenol A and epichlorohydrin or a polymerization product of bisphenol F and epichlorohydrin. Things. Further, these epoxy resins may contain a reactive diluent such as butyl glycidyl ether or phenyl glycidyl ether or a non-reactive diluent such as benzyl alcohol. The epoxy resin composition of the present invention may contain a filler and a pigment.

[0021]

EXAMPLES Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples. In the following Examples and Comparative Examples, the storage stability was evaluated by visually judging the appearance of the curing agent after storage at 5 ° C. for 3 months. Evaluation of the coating film was performed as follows. Dryness to the touch: The state of stickiness of the coating film surface is evaluated by touch. Appearance: The gloss, transparency and smoothness of the coating film are evaluated by visual judgment. Water resistance test: Drops of water are dropped on the coating film, and changes in the coating film after 24 hours are evaluated by visual judgment.

Production Example 1 284 g (2 mol) of 1,3-bis (aminomethyl) cyclohexane and 188 g of phenol (1 mol%) were placed in a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a reflux condenser, a dropping funnel and a water receiver. 2 mol), 108 g of formalin (37% aqueous solution containing 8% methanol) was added dropwise at 90 ° C. in about 1 hour while stirring under a nitrogen stream.
C., and the reaction was performed for 1.5 hours. The temperature was raised to 150 ° C. over 2 hours while dehydrating, and the reaction was carried out for 1 hour. The obtained reaction product was a pale yellow transparent liquid. This reaction product is designated as polyamine A.

Production Example 2 284 g (2 mol) of 1,3-bis (aminomethyl) cyclohexane was charged into a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a reflux condenser, and a dropping funnel.
At 80 ° C. with stirring, 152 g of bisphenol A diglycidyl ether (epoxy equivalent: 190 g / eq) was added for about 1 hour.
After completion of the dropwise addition, the temperature was raised to 100 ° C., and the reaction was carried out for 2 hours. The obtained reaction product was a pale yellow transparent liquid. This reaction product is designated as polyamine B.

Production Example 3 284 g (2 mol) of 1,3-bis (aminomethyl) cyclohexane and 231 g of dimer acid (acid equivalent) were placed in a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a reflux condenser, and a water receiver. 289 g / eq), and the mixture was reacted at 180 ° C. for 1 hour, 200 ° C. for 1 hour, and 230 ° C. for 2 hours while stirring under a nitrogen stream to distill off condensed water. The obtained reaction product was a brown transparent liquid. This reaction product is designated as polyamine C.

Production Example 4 284 g (2 mol) of 1,3-bis (aminomethyl) cyclohexane was charged into a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a reflux condenser, and a dropping funnel.
53 g of acrylonitrile (1 mo
1) was added dropwise in about 1 hour, and after completion of the addition, the temperature was raised to 100 ° C. and the reaction was carried out for 2 hours. The obtained reaction product was a pale yellow transparent liquid. This reaction product is designated as polyamine D.

Production Example 5 284 g (2 mol) of 1,3-bis (aminomethyl) cyclohexane was charged into a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a reflux condenser, and a dropping funnel.
100 g of methyl methacrylate (1
mol) was dropped in about 3 hours, and the reaction was carried out for 1 hour after completion of the dropping. The temperature was further raised to 170 ° C. over 1 hour, and the reaction was carried out for 3 hours while distilling off methanol. The obtained reaction product was a pale yellow transparent liquid. This reaction product is designated as polyamine E.

Examples 1 to 12 1,3-bis (aminomethyl) cyclohexane (1,3-bis (aminomethyl) cyclohexane in the table
BAC) or the polyamine compound shown in Production Example, a fatty amine compound, a curing accelerator and a non-reactive diluent were mixed in the proportions shown in Table 1, and the mixture was heated to a uniform state and cooled to room temperature. , An epoxy resin curing agent was prepared. The storage stability of these epoxy resin curing agents was evaluated. The results are shown in Tables 1 and 2. Subsequently, the obtained epoxy resin curing agent and epoxy resin (bisphenol A diglycidyl ether, epoxy equivalent 190 g /
eq) were mixed at the ratios shown in Tables 4 and 5, applied to a cold-rolled steel sheet to a thickness of 200 μm, and cured at 23 ° C. for 7 days to prepare a coating film. These coating films were evaluated for dryness to the touch (stickiness of the coating film), evaluation of appearance, and water resistance test. The results are shown in Tables 4 and 5.

COMPARATIVE EXAMPLES 1-6 A composition having no fatty amine compound and no curing accelerator as shown in Table 3 was added as an epoxy resin curing agent, and storage stability was evaluated. Table 3 shows the results.
Further, the obtained epoxy resin curing agent and the same epoxy resin as in the examples were mixed at a ratio shown in Table 6, and evaluation was performed in the same manner as in the examples. Table 6 shows the results.

Table 1 Example 1 2 3 4 5 6 Composition (weight ratio) of epoxy resin curing agent (1) 1,3-BAC 100 100 100---(2) Polyamine A---100 100-(3) ) Polyamine B-----100 (4) Polyamine C------(5) Polyamine D------(6) Polyamine E-------(7) Dodecylamine 15-- 12--(8) Palm alkylamine-15---12 (9) Oleylamine--15-10-(10) Soybean alkylamine------(11) DMP-30 33 3-3--( 12) Triphenyl phosphite--6-36 (13) Benzyl alcohol 10 10 10 10 10 10 Storage stability Good Good Good Good Good Good

Table 2 Example 7 8 9 10 11 12 Composition of epoxy resin curing agent (weight ratio) (1) 1,3-BAC------(2) Polyamine A----70-(3) ) Polyamine B 100----70 (4) Polyamine C-100----(5) Polyamine D--100-30 30 (6) Polyamine E---100--(7) Dodecylamine--15 -12-(8) Coconut alkylamine-12----(9) Oleylamine---12--(10) Soybean alkylamine 12----12 (11) DMP-30 33 3-3--( 12) Triphenyl phosphite--6-36 (13) Benzyl alcohol 10 10 10 10 10 10 Storage stability Good Good Good Good Good Good

Table 3 Comparative Example 1 2 3 4 5 6 Composition of epoxy resin curing agent (weight ratio) (1) 1,3-BAC 100-----(2) Polyamine A-100----(3) ) Polyamine B--100---(4) Polyamine C---100--(5) Polyamine D----100-(6) Polyamine E-----100 (13) Benzyl alcohol 10 10 10 10 10 10 Storage stability Good Good Good Good Good Good Good

In Tables 1 to 3, (1) to (6) are polyamine compounds (A) in the present invention, (7) to (10) are fatty amine compounds (B), and (11) to (12) are It is a curing accelerator (C). Benzyl alcohol (13) was used as a non-reactive diluent to reduce the viscosity of the curing agent. 1,3-BAC of (1)
Is 1,3-bis (aminomethyl) cyclohexane, D of (11)
MP-30 indicates 2,4,6-trisdimethylaminomethylphenol.

Table 4 Example 1 2 3 4 5 6 Resin formulation (weight ratio) Epoxy resin base 100 100 100 100 100 100 Epoxy resin hardener 23 23 24 46 46 39 Evaluation of coating film Dry to the touch EX EX EX EX EX EX Appearance gloss ◎ ◎ ◎ ◎ ◎ ◎ transparency ◎ ◎ ◎ ◎ ◎ ◎

Table 5 Example 7 8 9 10 11 12 Resin formulation (weight ratio) Epoxy resin base 100 100 100 100 100 100 Epoxy resin curing agent 39 50 32 45 40 37 Evaluation of coating film Dry to the touch EX EX EX EX EX EX Appearance gloss ◎ ◎ ◎ ◎ ◎ ◎ transparency ◎ ◎ ◎ ◎ ◎ ◎

Table 6 Comparative Example 1 2 3 4 5 6 Resin blending (weight ratio) Epoxy resin base agent 100 100 100 100 100 100 Epoxy resin curing agent 19 42 35 46 28 41 Evaluation of coating film Dry to the touch P GG F FF Appearance Gloss △ ○ ○ △ △ △ Transparency × ○ △ △ △ △ Smoothness ○ ○ ○ △ ○ ○ Water resistance 1 day later × △ △ △ △ △ 7 days later △ △ △ △ △ △

The evaluations of the coating films in Tables 4 to 6 are as follows. Dry to the touch EX: No stickiness at all, G: Slightly sticky, F: Sticky, P: Severe stickiness Appearance, water resistance ◎: Excellent, ○: Good, △: Slightly poor, ×: Poor

[0037]

As is clear from the above examples, the epoxy resin curing agent of the present invention is excellent in storage stability, and is a disadvantage of the conventional bis (aminomethyl) cyclohexane-based epoxy resin curing agent. The tackiness of the applied coating is eliminated, and an epoxy resin coating excellent in water resistance is obtained. Moreover, by using the epoxy resin curing agent of the present invention,
It becomes a coating film with excellent gloss, transparency and smoothness. Therefore, according to the present invention, it is possible to obtain an epoxy resin composition which is extremely useful for coating materials, flooring materials, coating materials used for anticorrosion of metals and concretes and the like, and the present invention has great industrial significance.

Claims (7)

[Claims] 1. A polyamine compound (A) containing bis (aminomethyl) cyclohexane and / or a modified product thereof,
Fatty amine compound (B) containing a component having an alkyl group having 12 carbon atoms or having an iodine value of 50 or more
And a curing accelerator (C). 2. A modified product of bis (aminomethyl) cyclohexane is obtained by a Mannich reaction of bis (aminomethyl) cyclohexane with a phenolic compound or an aldehyde compound, or a modified product of bis (aminomethyl) cyclohexane with an epoxy compound. At least one polyamine compound selected from a modified product, a modified product obtained by the reaction of bis (aminomethyl) cyclohexane with a compound having a carboxyl group, and a modified product obtained by the Michael reaction of bis (aminomethyl) cyclohexane with an acrylic compound ( The epoxy resin curing agent according to claim 1, which is A). 3. The epoxy resin curing agent according to claim 1, wherein 5 to 15 parts by weight of the fatty amine compound (B) is blended with respect to 100 parts by weight of the polyamine compound (A). 4. The epoxy resin curing agent according to claim 1, wherein the fatty amine compound (B) contains at least 50% of a component having an alkyl group having 12 carbon atoms. 5. The fatty amine compound (B) having an iodine value of 50
The epoxy resin curing agent according to claim 1, which is the above. 6. The epoxy resin curing agent according to claim 1, wherein 3 to 10 parts by weight of a curing accelerator (C) is blended with 100 parts by weight of the polyamine compound (A). 7. An epoxy resin composition comprising the epoxy resin curing agent according to claim 1 and an epoxy resin.