JP3649497B2 - Curing agent composition for epoxy resin - Google Patents

Description

【００５３】
上記〔表１〕の結果から、以下のことが明らかである。
少量の多塩基酸〔前記特定量の前記（Ｂ）成分〕でアミド化されたポリアミノアミド化合物を有効成分とする本発明のエポキシ樹脂用硬化剤組成物（実施例；硬化剤１〜９）を用いた硬化性組成物は、長期間に渡って優れた防食効果を示し、また、耐熱性、耐水性、耐薬品性に優れているばかりでなく、硬化性も良好であり、塗布後短時間でタッキングが認められなくなる。
【００５４】
これに対し、多量の多塩基酸でアミド化しようとした場合には、イミド化も同時に進行し、このようなポリアミノアミド−イミド化合物を有効成分とする硬化剤組成物（比較例；硬化剤１０）を用いた硬化性組成物は、エポキシ樹脂との相溶性および硬化性が劣り、また、防食性、耐熱性、耐水性、耐薬品性についても不十分であり、また、二塩基酸でアミド化したポリアミノアミド化合物を有効成分とする硬化剤組成物（比較例；硬化剤１１）を用いた硬化性組成物は、エポキシ樹脂との相溶性および硬化性は良好なものの、防食性、耐熱性、耐水性、耐薬品性に著しく劣り、過酷な条件下で使用される場合には不十分である。
【００５５】
【発明の効果】
本発明のエポキシ樹脂用硬化剤組成物は、エポキシ樹脂との相溶性に優れ、また、常温における硬化性に優れるばかりでなく、防食性、耐熱性、耐水性、耐薬品性に優れた被膜を形成させることができるものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a curing agent used for curing an epoxy resin, in particular, an epoxy resin used as a paint, an adhesive, and the like. Specifically, a polyaminoamide compound amidated with a trivalent or higher polycarboxylic acid is effectively used. It is related with the hardening | curing agent composition for epoxy resins contained as a component.
[0002]
[Prior art and problems to be solved by the invention]
Epoxy resins have excellent adhesion to various substrates, and cured products obtained by curing epoxy resins with curing agents are relatively excellent in heat resistance, chemical resistance, electrical properties, mechanical properties, etc. Therefore, it is used in a wide range of industrial fields, particularly in the field of paints and adhesives.
[0003]
As a curing agent used for curing an epoxy resin, an organic amine compound and / or a modified amine compound obtained by subjecting the organic amine compound to a modification treatment such as amidation, imidization, epoxy addition, Mannichation, or Michael addition is used. This is well known. And since it is possible to change the curing rate and the properties of the cured product by changing the type of the modification treatment and the ratio of the modification, a curing agent according to the purpose is obtained by appropriately adjusting these modification treatments. It is being considered.
[0004]
Among these modification treatments, when amidation or imidation modification with a monovalent or polyvalent carboxylic acid is performed, a cured product having relatively good characteristics such as heat resistance can be obtained. As the use of resins expands, the performance requirements for curing agents are becoming higher, especially those with excellent heat resistance, corrosion resistance, and chemical resistance, and the curing rate at room temperature. The fast ones are now required.
[0005]
For example, a polyaminoamide compound obtained by amidating and modifying an organic polyamine compound with a monobasic acid or a dibasic acid has insufficient curability, water resistance, chemical resistance and the like, and is not satisfactory in practical use.
[0006]
JP-A 61-166828 discloses a polyaminoimide obtained by reacting an aromatic diamine and an aromatic tetracarboxylic acid anhydride in a molar ratio of 1.2 / 1 to 4/1. Although it has been proposed as a curing agent that can give a cured product having heat resistance, when such a polyaminoimide is used, it usually does not cure unless it is heated to 150 ° C. or higher. However, it could not be used for applications that require.
[0007]
Accordingly, an object of the present invention is to provide a curing agent composition for epoxy resins that is not only excellent in heat resistance, water resistance, chemical resistance, etc., but also excellent in curability.
[0008]
[Means for Solving the Problems]
As a result of intensive studies, the present inventors have found that the above object can be achieved by using a modified product obtained by amidating an organic polyamine compound with a small amount of a tribasic or higher polycarboxylic acid as a curing agent. I found out.
[0009]
  The present invention has been made based on the above findings, and (A) at least one organic polyamine compound having two or more primary amino groups in one molecule, and (B) three or more carboxyl groups in one molecule. A polycarboxylic acid havingAcid anhydride or acid halideA polyaminoamide compound obtained by reacting at least one of the above with a ratio of 0.02 to 0.3 carboxyl groups constituting the component (B) to one primary amino group of the component (A) is effective. Contains as an ingredientAnd xylylenediamine was used as the component (A).An epoxy resin curing agent composition is provided.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the curing agent composition for epoxy resin of the present invention will be described in detail.
[0011]
The organic polyamine compound having two or more primary amino groups in one molecule which is the component (A) used in the present invention is a raw material for the polyaminoamide compound which is an effective component of the curing agent composition for epoxy resins of the present invention. It is used. Examples of the organic polyamine compound include an aliphatic polyamine compound, an alicyclic polyamine compound, an aromatic polyamine compound, and a heterocyclic polyamine compound, and specific examples thereof are shown below.
[0012]
Examples of the aliphatic polyamine compound include ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, hexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, diethylenetriamine, and dipropylene. Examples include triamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, dimethylaminopropylamine, and diethylaminopropylamine.
[0013]
Examples of the alicyclic polyamine compound include mensendiamine, 1,3-bis (aminomethyl) cyclohexane, isophoronediamine, N-3-aminopropylcyclohexylamine, 1,4-diaminocyclohexane, 2,4-diaminocyclohexane, Examples include bis (aminocyclohexyl) methane, 1,3-bis (aminocyclohexylpropane), bis (3-methyl-4-aminocyclohexyl) methane, 1,4-bis (ethylamino) cyclohexane, and the like.
[0014]
Examples of the aromatic polyamine compound include m-xylylenediamine, p-xylylenediamine, 4- (1-aminoethyl) aniline, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, and bis (3-ethyl-4-amino). -5-methylphenyl) methane, 1,4-bis (2- (3,5-dimethyl-4-aminophenyl) propyl) benzene and the like.
[0015]
Examples of the heterocyclic polyamine compound include N-aminoethylpiperazine, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxaspiro [5.5] undecane.
[0016]
  In the present invention, among the above-mentioned organic polyamine compounds, an alicyclic polyamine compound or aromatic polyamine compound having a cyclic hydrocarbon group, particularly when xylylenediamine is used, curing excellent in corrosion resistance, chemical resistance, etc. Since you can get things (AAs part or all of the organic polyamine compounds that are components)XylylenediamineUsingThe
[0017]
  In addition, a polycarboxylic acid having 3 or more carboxyl groups in one molecule (component (B)) used in the present invention (hereinafter also referred to as “trivalent or higher polycarboxylic acid”) or itsAcid anhydride or acid halideIs used to obtain the polyaminoamide compound as the effective component by amidating and modifying the organic polyamine compound as the component (A). Examples of the trivalent or higher polycarboxylic acid include aliphatic, alicyclic, aromatic or heterocyclic polycarboxylic acids, and specifically include tricarbaric acid, citric acid, 1,2,3-butane. Tricarboxylic acid, 1,2,3-butenetricarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, trimellitic acid, trimesic acid, pyromellitic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic Acid, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid, etc.Be. In particular, a polycarboxylic acid having 4 or more carboxyl groups in one molecule or itsAcid anhydride or acid halideAnd / or aromatic polycarboxylic acid or itsAcid anhydride or acid halideIn particular, pyromellitic acid or itsAcid anhydride or acid halideIs preferable because a cured product having excellent characteristics can be obtained.
[0018]
  Polycarboxylic acid as component (B) or itsAcid anhydride or acid halideIs used in an amount of from 0.02 to 0.3, preferably from 0.04 to 0.14 carboxyl groups constituting the component (B) with respect to one primary amino group of the organic polyamine compound as the component (A). The amount is 0.2. When the amount of the component (B) used is such that the carboxyl group is less than 0.02, the effect of modification with polycarboxylic acid is hardly observed, and the carboxyl group has 0.3 carboxyl group. If the amount exceeds the above, gelation may cause difficulty in use, or imidization may progress, and not only the compatibility with the epoxy resin is deteriorated, but also the curability is remarkably lowered.
[0019]
  These polycarboxylic acids or theirAcid anhydride or acid halideIt is conceivable that a part of the carboxyl group remains unreacted or undergoes imidation when the transformation is carried out by the above, but most of the carboxyl group is amidated when reacted at a ratio in the above range. Therefore, the adverse effect of the unreacted carboxyl group and by-product imide group is virtually negligible.
[0020]
  In the present invention, the organic polyamine compound as the component (A) is added in a small amount (the amount used in the above range) of the trivalent or higher polycarboxylic acid as the component (B) or itsAcid anhydride or acid halideBy the amidation modification, a curing agent can be obtained that can give a cured product with excellent properties such as water resistance and chemical resistance, but other properties such as adjusting the curability and the surface finish of the cured product. In order to improve the above, the (B) component trivalent or higher polycarboxylic acid or itsAcid anhydride or acid halideIt is preferable to perform other modification treatment in addition to the amidation modification.
[0021]
Examples of the other modification treatment include at least one modification treatment selected from the group consisting of amidation modification with monobasic acid and dibasic acid, epoxy addition modification, Mannich modification, and Michael addition modification. By further performing the treatment, the curability is adjusted, and a cured product having a quick curing rate at room temperature and a pot life that can withstand actual use can be obtained.
[0022]
Examples of the monobasic acid or dibasic acid used for the amidation modification with the above monobasic acid and dibasic acid include octylic acid, decanoic acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, ricinoleic acid. , Behenic acid, benzoic acid, toluic acid, cyclohexanecarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, isophthalic acid, terephthalic acid, phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid And aliphatic, alicyclic or aromatic carboxylic acids such as hexahydrophthalic acid.
[0023]
Moreover, as an epoxy compound used for the said epoxy addition modification | denaturation, the compound which has 1 or more than 1 average epoxy group in a molecule | numerator can be especially used without a restriction | limiting.
[0024]
Here, examples of the compound having one epoxy group in the molecule include octene oxide, dodecane oxide, styrene oxide, butyl glycidyl ether, phenyl glycidyl ether, and neodecanoic acid glycidyl ester.
[0025]
Examples of the compound having an average of more than one epoxy group in the molecule include resorcinol, hydroquinone, pyrocatechol, phloroglucinol, dihydroxynaphthalene, biphenol, methylene bisphenol (bisphenol F), and methylene bis (orthocresol). ), Ethylidene bisphenol, isopropylidene bisphenol (bisphenol A), isopropylidene bis (orthocresol), tetrabromobisphenol A, bis (hydroxyphenyl) phenylmethane, bis (hydroxyphenyl) cyclohexylmethane, cyclocyclohexylidene bisphenol, thio Bisphenol, sulfobisphenol (bisphenol S), oxybisphenol, 1,3-bis (4-hydroxycumyl) benze , 1,4-bis (4-hydroxycumyl) benzene, polyglycidyl ethers of mononuclear or polynuclear polyhydric phenols such as phenol-formaldehyde condensates; ethylene glycol, propylene glycol, butylene glycol, hexanediol, polyglycol, Glycidyl ethers of polyhydric alcohols such as thiodiglycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, bisphenol A-ethylene oxide adduct; maleic acid, fumaric acid, itaconic acid, succinic acid, glutaric acid, suberic acid, adipine Acid, azelaic acid, sebacic acid, dimer acid, trimer acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid, pyromellitic acid, tetrahydrophthalic acid, hexahydrophthalic acid Glycidyl esters of aliphatic, aromatic or alicyclic polybasic acids such as endomethylenetetrahydrophthalic acid; homopolymers or copolymers of glycidyl methacrylate; epoxidized soybean oil, epoxidized linseed oil, epoxidized safflower Oil, epoxidized natural oil such as epoxidized tall oil; vinylcyclohexene diepoxide, dicyclopentadiene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6-methyl Epoxidized products of cyclic olefin compounds such as cyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate; epoxidized polybutadiene, epoxidized polystyrene Examples thereof include epoxidized conjugated diene polymers such as a lene-butadiene copolymer; and heterocyclic compounds such as triglycidyl isocyanurate.
[0026]
Further, the Mannich modification is a process in which a phenol compound and formaldehyde are reacted with an organic polyamine compound to form a Mannich base. Examples of the phenol compound that can be used for the Mannich modification include phenol, cresol, xylenol, and ethylphenol. Phenol compounds in which at least one of the ortho-position and / or para-position of the phenolic hydroxyl group such as butylphenol, nonylphenol, bisphenol A and the like is unsubstituted can be used.
[0027]
The Michael addition modification is to add an olefin compound to the organic polyamine compound or the polyaminoamide compound. Examples of the olefin compound that can be used for the Michael addition modification include acrylonitrile and methyl (meth) acrylate. Conventionally known compounds can be used.
[0028]
Among the other modification treatments described above, when amidation modification with a monobasic acid or a dibasic acid is performed, a particularly excellent effect is exhibited, which is preferable. In addition, in the case where two or more of these modification treatments are performed in combination, amidation modification with monobasic acid or dibasic acid such as a combination of amidation modification with monobasic acid or dibasic acid and epoxy addition modification is included. It is preferable to perform a modification treatment.
[0029]
The timing of performing the other modification treatment is not particularly limited, and the other modification treatment is performed in advance prior to the amidation modification by the component (B), and at the same time as the amidation modification by the component (B). Other modification treatments can be performed, or the other modification treatment can be performed after the amidation modification by the component (B).
[0030]
In the above other modification treatment, the primary amino group of the organic polyamine compound which is the component (A) or one primary amino group of the polyaminoamide compound has 0.02 to 0 groups related to the other modification treatment. It is preferable to carry out the reaction at a ratio of 5. Particularly, in combination with the amidation modification by the component (B), the number of groups involved in the modification treatment is 0.04 to 1 per primary amino group of the organic polyamine compound. It is preferable to carry out at a ratio of 0.8, especially 0.1 to 0.5. When these modification treatments are performed at a ratio that is less than the lower limit of the above range, the pot life is short, and when performed at a ratio that exceeds the upper limit of the above range, not only the curing rate becomes insufficient, but also the activity Since the hydrogen equivalent increases, a large amount of curing agent must be used.
[0031]
In addition, the epoxy resin curing agent composition of the present invention can be added with a solvent for the purpose of reducing the viscosity, or dispersed in water by adding a surfactant according to the purpose of use, It can also be set as an aqueous hardening | curing agent composition. Furthermore, well-known reaction accelerators, such as a phenol compound and an alcohol compound, can be added, and it can also be used in combination with another hardening | curing agent.
[0032]
The epoxy resin cured by the epoxy resin curing agent composition of the present invention is not particularly limited in its structure and the like as long as it is a compound having an average of more than one epoxy group in the molecule that is usually used. A compound having an average of more than one epoxy group in the molecule used for the epoxy addition modification can be used as it is.
[0033]
The said epoxy resin can be used individually or in mixture of 2 or more types, Moreover, a solvent, a monoepoxy compound, etc. can also be added as needed. Further, the epoxy resin may be a so-called emulsified epoxy resin emulsified in advance using a surfactant such as a polyoxyethylene alkylphenyl ether compound.
[0034]
In the curing agent composition for epoxy resin of the present invention, the active hydrogen group of the active ingredient in the curing agent composition is preferably 0.7 to 1.5 with respect to one epoxy group of the epoxy resin. It is used so that it may become a piece, More preferably 0.8-1.2 pieces. When the amount of the curing agent composition for epoxy resin of the present invention is less than the lower limit of the above range, the curing rate becomes remarkably insufficient, and when it exceeds the upper limit of the above range, it is not only useless but also cured. There is a risk of deteriorating the properties of the object.
[0035]
The curing agent composition for epoxy resin of the present invention comprises the above-mentioned epoxy resin and a reactive diluent, a non-reactive diluent, a filler, a reinforcing agent, a pigment, a dye, a solvent, a plasticizer, a level dyeing used as necessary. It is used as a curable composition of a solvent type, a solventless type, or an aqueous type together with conventional additives such as an agent, a thixotropic agent, a flame retardant, and a release agent.
[0036]
The curable composition is applied to the substrate by an appropriate method such as brush coating, roller, spray, spatula coating, press coating, doctor blade coating, electrostatic coating, electrodeposition coating, dip coating, or the like. Used as an undercoat or intermediate coating, filler, sealant, protective coating, coating material, sealing material, mortar, coating material, etc. Since it has a pot life and gives a cured product excellent in corrosion resistance, chemical resistance, water resistance and adhesion, for example, as a solvent type or a solvent-free type, it is suitable for the corrosion protection of land and marine structures and ships. Anti-corrosion paint or structural adhesives for automobiles, building materials related metal, such as iron, aluminum, stainless steel, water-based construction on land In particular, the handling of dangerous goods are suitable for use in anticorrosive paints, such as sealing points or apartment becomes a problem.
[0037]
【Example】
  EXAMPLES Hereinafter, although this invention is demonstrated in detail with a manufacture example and a use example, this invention is not restrict | limited by the following manufacture examples and use examples.However, the following Production Example 2 is a reference production example.The following manufacturing examplesAnd reference production examplesIn the formula, “epoxy equivalent” represents the molecular weight of the epoxy compound (resin) per epoxy group, and “active hydrogen equivalent” represents the molecular weight of the amine compound per hydrogen atom of the amine. When used, it represents the apparent molecular weight including the solvent. In each example, “part” means “part by weight”.
[0038]
Production Example 1
In a glass flask equipped with a thermometer, a stirrer, and a condenser tube, 544 parts of metaxylylenediamine, 21.8 parts of pyromellitic anhydride [ratio in which the number of carboxyl groups is 0.05 with respect to one amino group ( In this case, the carboxyl group represents a carboxyl group constituting an acid anhydride, the same shall apply hereinafter)] and p-toluenesulfonic acid 1.9 parts as a catalyst, heated to dissolve uniformly, While removing, the mixture was stirred at 240 ° C. for 5 hours to obtain a product.
The product obtained has a viscosity of 800 cps (25 ° C.), and as a result of infrared spectroscopic analysis of the product, absorption due to the acid anhydride disappeared, and 1660 cm^-1The absorption derived from the amide bond is expressed in 1700 cm derived from the imide bond.^-1Since no near absorption was observed, it was confirmed to be an amidated condensate. This product was designated as curing agent 1 (active hydrogen equivalent = 36).
[0039]
Production Example 2
In a glass flask equipped with a thermometer, a stirrer, and a condenser tube, 568 parts of 1,3-bis (aminomethyl) cyclohexane and 43.6 parts of pyromellitic acid anhydride (carboxyl group was reduced to 0. 1 amino group). 1), 33.2 parts of methyltetrahydrophthalic anhydride (a ratio of 0.05 carboxyl groups to 1 amino group) and 1.9 parts of paratoluenesulfonic acid as a catalyst, After heating and dissolving uniformly, the product was obtained by stirring at 240 ° C. for 5 hours while removing distilled water.
The viscosity of the obtained product is 1600 cps (25 ° C.), and as a result of infrared spectroscopic analysis of the product, the absorption due to the acid anhydride disappears, the absorption derived from the amide bond appears, and the imide bond From the fact that no absorption derived from was observed, it was confirmed to be an amidated condensate. This product was named curing agent 2 (active hydrogen equivalent = 48).
[0040]
Production Example 3
In a glass flask equipped with a thermometer, a stirrer and a condenser, 544 parts of metaxylylenediamine and 76 parts of bisphenol A-diglycidyl ether type epoxy resin (epoxy equivalent 190) (0 epoxy group per one amino group) .05 ratio) was added, and the mixture was stirred at 80 ° C. for 5 hours for reaction to carry out epoxy addition modification.
Next, 21.8 parts of pyromellitic anhydride (ratio of 0.05 carboxyl groups to one amino group), 33.2 parts of methyltetrahydrophthalic anhydride (carboxyl to one amino group) The ratio of 0.05 groups) and 1.9 parts of p-toluenesulfonic acid as a catalyst, heated to 200 ° C. and dissolved uniformly, and stirred at 240 ° C. for 5 hours while removing distillate. The product was obtained.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
To this product, 74 parts of phenol as a curing accelerator was added to obtain a curing agent 3 (active hydrogen equivalent = 52) having a viscosity of 3200 cps (25 ° C.).
[0041]
Production Example 4
In a glass flask equipped with a thermometer, a stirrer and a condenser, 544 parts of metaxylylenediamine and 76 parts of bisphenol A-diglycidyl ether type epoxy resin (epoxy equivalent 190) (0 epoxy group per one amino group) .05 ratio) was added, and the mixture was stirred at 80 ° C. for 5 hours for reaction to carry out epoxy addition modification.
Next, 21.8 parts of pyromellitic anhydride (ratio of 0.05 carboxyl group to 1 amino group), 33.2 parts of isophthalic acid (carboxyl group 0. 1 amino group). 05 ratio) and 1.9 parts of para-toluenesulfonic acid as a catalyst, heated to 200 ° C. and uniformly dissolved, stirred at 240 ° C. for 5 hours while removing distillate water, Got.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
To this product, 74 parts of phenol as a curing accelerator was added to obtain a curing agent 4 (active hydrogen equivalent = 52) having a viscosity of 3200 cps (25 ° C.).
[0042]
Production Example 5
In a glass flask equipped with a thermometer, a stirrer and a condenser tube, 544 parts of metaxylylenediamine, 38 parts of bisphenol A-diglycidyl ether type epoxy resin (epoxy equivalent 190) (0 epoxy group per one amino group) 0.025) and 26 parts of butyl glycidyl ether (ratio of 0.025 epoxy groups to one amino group), and stirred for 5 hours at 80 ° C. and reacted to effect epoxy addition modification. went.
Next, 21.8 parts of pyromellitic anhydride (ratio of 0.05 carboxyl group to 1 amino group), 33.2 parts of isophthalic acid (carboxyl group 0. 1 amino group). 05 ratio) and 1.9 parts of para-toluenesulfonic acid as a catalyst, heated to 200 ° C. and uniformly dissolved, stirred at 240 ° C. for 5 hours while removing distillate water, Got.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
To this product, 74 parts of phenol was added, and 32.4 parts of 37% formalin was gradually added dropwise and stirred while dehydrating at 120 ° C. for 2 hours to modify Mannich conversion (Mannich base formation was 0 for one amino group). .05 ratio).
To the Mannich-modified product, 100 parts of toluene and 100 parts of isopropanol were added to adjust the viscosity to 400 cps (25 ° C.) to obtain a curing agent 5 (active hydrogen equivalent = 69).
[0043]
Production Example 6
In a glass flask equipped with a thermometer, a stirrer and a condenser tube, 544 parts of metaxylylenediamine and 78.5 parts of pyromellitic anhydride (a ratio of 0.18 carboxyl groups to one amino group) , 33.2 parts of isophthalic acid (ratio of 0.05 carboxyl groups to one amino group) and 1.9 parts of paratoluenesulfonic acid as a catalyst, heated to 200 ° C. and uniformly dissolved The mixture was stirred at 240 ° C. for 5 hours while removing distilled water to obtain a product.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
Next, 76 parts of bisphenol A-diglycidyl ether type epoxy resin (epoxy equivalent 190) (ratio in which the number of epoxy groups is 0.05 with respect to one amino group) is added, and the mixture is reacted by stirring at 80 ° C. for 5 hours. Epoxy addition modification was performed to obtain a product having a viscosity of 5100 cps (25 ° C.). This product was designated as a curing agent 6 (active hydrogen equivalent = 66).
[0044]
Production Example 7
In a glass flask equipped with a thermometer, a stirrer, and a condenser tube, 408 parts of metaxylylenediamine, 170 parts of isophoronediamine, 21.8 parts of pyromellitic anhydride (the carboxyl group is 0.1% relative to one amino group). 05), 33.2 parts of isophthalic acid (ratio of 0.05 carboxyl groups to one amino group) and 1.9 parts of paratoluenesulfonic acid as a catalyst The mixture was dissolved uniformly by heating, and stirred at 240 ° C. for 5 hours while removing distillate water to obtain a product.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
Next, 72 parts of cresyl glycidyl ether (ratio in which the number of epoxy groups was 0.05 with respect to one amino group) was added, and the mixture was stirred at 80 ° C. for 5 hours to effect epoxy addition modification.
78 parts of xylene resin was added thereto to obtain a curing agent 7 (active hydrogen equivalent = 55) having a viscosity of 700 cps (25 ° C.).
[0045]
Production Example 8
In a glass flask equipped with a thermometer, a stirrer, and a condenser tube, 408 parts of metaxylylenediamine, 146 parts of triethylenetetramine, 21.8 parts of pyromellitic anhydride (the number of carboxyl groups is 0 for one primary amino group). .05), 33.2 parts of isophthalic acid (ratio of 0.05 carboxyl groups to one amino group) and 1.9 parts of paratoluenesulfonic acid as a catalyst, up to 200 ° C. The mixture was heated to dissolve uniformly, and stirred at 240 ° C. for 5 hours while removing distilled water to obtain a product.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
Next, 72 parts of cresyl glycidyl ether (ratio in which the number of epoxy groups was 0.05 with respect to one amino group) was added, and the mixture was stirred at 80 ° C. for 5 hours to effect epoxy addition modification.
To this was added 75 parts of xylene resin to obtain a curing agent 8 (active hydrogen equivalent = 47) having a viscosity of 650 cps (25 ° C.).
[0046]
Production Example 9
To a glass flask equipped with a thermometer, stirrer and condenser, 544 parts of metaxylylenediamine, 23.4 parts of 1,2,3,4-butanetetracarboxylic acid (carboxyl group is 0 with respect to one amino group) 0.05), 33.2 parts of methyltetrahydrophthalic anhydride (ratio of 0.05 carboxyl groups to one amino group) and 1.9 parts of paratoluenesulfonic acid as a catalyst. The mixture was heated up to 200 ° C. and dissolved uniformly, and stirred at 240 ° C. for 5 hours while removing distilled water to obtain a product.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
Next, 76 parts of bisphenol A-diglycidyl ether type epoxy resin (epoxy equivalent 190) (ratio in which the number of epoxy groups is 0.05 with respect to one amino group) is added, and the mixture is reacted by stirring at 80 ° C. for 5 hours. Then, epoxy addition modification was performed.
To this epoxy addition-modified product, 74 parts of phenol as a curing accelerator was added to obtain a curing agent 9 (active hydrogen equivalent = 52) having a viscosity of 2800 cps (25 ° C.).
[0047]
Comparative production example 1
In a glass flask equipped with a thermometer, a stirrer and a condenser tube, 544 parts of metaxylylenediamine, 218 parts of pyromellitic anhydride (ratio in which 0.5 carboxyl group per amino group) and catalyst After taking 1.9 parts of paratoluenesulfonic acid and heating to dissolve uniformly, the product was obtained by stirring at 240 ° C. for 5 hours while removing distilled water.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappeared and 1660 cm^-1The absorption derived from the amide bond is also 1700 cm^-1Since the absorption derived from the imide bond was expressed, it was confirmed that it was an amide-imidized condensate. This semi-solid product at room temperature was designated as curing agent 10 (active hydrogen equivalent = 91).
[0048]
Comparative production example 2
In a glass flask equipped with a thermometer, a stirrer, and a condenser tube, 544 parts of metaxylylenediamine, 66.4 parts of methyltetrahydrophthalic anhydride (a ratio of 0.1 carboxyl group to 1 amino group) ) And 1.9 parts of p-toluenesulfonic acid as a catalyst, heated to 200 ° C. and uniformly dissolved, and stirred at 240 ° C. for 5 hours while removing distilled water to obtain a product.
As a result of infrared spectroscopic analysis of the obtained product, absorption due to acid anhydride disappears, absorption due to amide bond appears, and absorption due to imide bond is not recognized, so amidated condensation It was confirmed to be a thing.
Next, 76 parts of bisphenol A diglycidyl ether type epoxy resin (epoxy equivalent 190) (ratio in which the number of epoxy groups is 0.05 with respect to one amino group) is added and stirred at 80 ° C. for 5 hours to react. Epoxy addition modification was performed.
76 parts of phenol as a curing accelerator was added to this epoxy addition-modified product to obtain a curing agent 11 (active hydrogen equivalent = 51) having a viscosity of 500 cps (25 ° C.).
[0049]
Use example 1 (use example as paint)
Each curing agent composition having the blending amount shown in Table 1 below is blended with 190 parts by weight of an epoxy equivalent of bisphenol A diglycidyl ether type epoxy resin so that the epoxy equivalent and the active hydrogen equivalent are equal. A product was prepared. Under the present circumstances, the compatibility with an epoxy resin and a hardening | curing agent composition was determined visually according to the following (1) reference | standard. Next, a curable composition was applied to a mild steel plate polished with # 280 sandpaper to a dry film thickness of 100 μm, and then cured at room temperature for 1 week to obtain a test piece.
Using this test piece, the following tests (2) to (4) were performed according to each standard according to JIS K5400, and the presence or absence of tacking after 24 hours of application was determined by finger touch. The results are shown in [Table 1] below.
[0050]
(1) Compatibility: The state when the epoxy resin and the curing agent were mixed at room temperature was observed.
○: Dissolved uniformly.
X: There is turbidity.
(2) Salt spray test (SST): The surface state after 500 hours and 1000 hours was observed.
○: Same as initial, no abnormality.
Δ: Spot rust occurred.
X: Full surface rusting.
[0051]
(3) Hot water immersion test: The surface state after immersion in boiling water for 3 days was observed.
○: Same as initial, no abnormality.
Δ: Scarlet color is observed.
X: Swelling or peeling occurs.
(4) Methanol immersion test: The surface state after immersion for 7 days at 25 ° C. was observed.
○: Same as initial, no abnormality.
Δ: Softening is observed.
X: Swelling or cracking occurs.
[0052]
[Table 1]

[0053]
From the results of [Table 1] above, the following is clear.
A curing agent composition for epoxy resins of the present invention (Examples; curing agents 1 to 9) comprising a polyaminoamide compound amidated with a small amount of a polybasic acid [the specific amount of the component (B)] as an active ingredient. The curable composition used has an excellent anticorrosive effect over a long period of time, is not only excellent in heat resistance, water resistance, and chemical resistance, but also has good curability and is short after application. Tacking is no longer allowed.
[0054]
On the other hand, when amidation is attempted with a large amount of polybasic acid, imidization also proceeds simultaneously, and a curing agent composition containing such a polyaminoamide-imide compound as an active ingredient (Comparative Example; Curing Agent 10 ) Is inferior in compatibility with epoxy resin and curability, and is insufficient in anticorrosion, heat resistance, water resistance, and chemical resistance. The curable composition using the cured polyaminoamide compound as an active ingredient (Comparative Example; Curing Agent 11) has good compatibility and curability with the epoxy resin, but has anticorrosion and heat resistance. It is extremely inferior in water resistance and chemical resistance, and is insufficient when used under severe conditions.
[0055]
【The invention's effect】
The curing agent composition for epoxy resin of the present invention is excellent in compatibility with epoxy resin, and not only has excellent curability at room temperature, but also has a coating excellent in corrosion resistance, heat resistance, water resistance, and chemical resistance. It can be formed.

Claims (5)

(A) at least one organic polyamine compound having two or more primary amino groups in one molecule; and (B) a polycarboxylic acid having three or more carboxyl groups in one molecule, or an acid anhydride or acid halide thereof. A polyaminoamide compound obtained by reacting at least one of the above with a ratio of 0.02 to 0.3 carboxyl groups constituting the component (B) to one primary amino group of the component (A) is effective. A curing agent composition for epoxy resins containing xylylenediamine as the component (A) .   The primary amino group of the organic polyamine compound or the primary amino group of the polyaminoamide compound is at least selected from the group consisting of amidation modification with monobasic acid and dibasic acid, epoxy addition modification, Mannich modification, and Michael addition modification The hardening | curing agent composition for epoxy resins of Claim 1 modified | denatured by a kind of modification | denaturation process.   The modification is performed at a ratio of 0.02 to 0.5 groups related to the modification with respect to one primary amino group of the organic polyamine compound or one primary amino group of the polyaminoamide compound. The hardening | curing agent composition for epoxy resins of description. The hardening | curing agent composition for epoxy resins in any one of Claims 1-3 which used aromatic polycarboxylic acid or its acid anhydride or acid halide as said (B) component. As the aromatic polycarboxylic acids or their anhydrides or acid halides, pyromellitic acid or Claim 4 curing agent composition for epoxy resins according to using the acid anhydride or acid halide.