JPH11279264A - Production of polyepoxide-based curable composition and cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a curable composition capable of giving a cured product with favorable surface disposition without being influenced by the environment in curing even under low-temperature and, furthermore, high-humidity circumstances as well as under heating and at normal temperatures. SOLUTION: This curable composition comprises an epoxide bearing on average at least one epoxide group in one molecule, a polyepoxide, or a mixture thereof, and as a polyamine-based curing agent, 1,3-bis(5-amino-2- methoxypentoxy)benzene, typical of bis(5-amino-2-alkoxypentoxy)(alkyl)benzenes. When this composition is used in the form of coating material, adhesive, sealant, casting agent, injection agent, laminating agent, impregnant, or the like, no defect is developed on the surface of the cured product of the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyepoxide-based curable composition. The epoxide or polyepoxide used in the curable composition has one or more active epoxide groups in the molecule. These epoxide groups react when mixed with various compounds having active hydrogen atoms. Due to this property, the epoxide and the compound having an active hydrogen atom rapidly or gradually increase in molecular weight depending on the environment and the conditions of the formulation, and finally solidify. This phenomenon is generally called curing. Compounds having these active hydrogen atoms are called curing agents for polyepoxide resins. Polyepoxide-based curable compositions combining an epoxide and a curing agent have been applied to various fields by utilizing the curability thereof, and have been applied to coatings, adhesives, injection repair agents, casting agents, potting agents, and electronic devices. It is used as a sealant for parts. The polyepoxide-based curable composition of the present invention can also be used for these applications.

[0002]

Hitherto, various types of polyamines have been used as curing agents for polyepoxide-based compositions. Among these, the aliphatic polyamine most frequently used has been used. Aliphatic polyamines are mostly liquids and have low viscosities. It has a property of reacting with an epoxide and hardening even at room temperature, and has been applied to many fields as a very simple and functional hardener compound.

A polyepoxide-based curable composition using an aliphatic polyamine as a curing agent has an advantage of curing at room temperature, but has a fatal disadvantage. That is, when cured as it is in combination with the epoxide compound at room temperature or low temperature, particularly in a high humidity environment, only a cured product having a defect on the surface can be obtained.

Among the aliphatic polyamines used as a curing agent component, polyethylene polyamines including diethylene triamine and triethylene tetramine, which are most used, and other non-aliphatic amines such as xylylenediamine and isophoronediamine Considering polyoxyalkylenediamines, the following can be said. When polyethylenepolyamine is mixed with a polyepoxide and cured, a sticky substance or a solid whitened substance is formed on the surface of the cured product, and the resulting cured product has a reduced surface gloss and an apparent surface condition. Even if it looks good, it shows a phenomenon of whitening upon contact with moisture. Also, when xylylenediamine, isophoronediamine, and even polyoxypropylenediamine as a curing agent, unlike the case of polyethylene polyamine,
Cured products generally show good surface conditions, but sometimes exhibit the phenomenon of whitening of the coating surface, and depending on the intrinsic properties of the individual amines, when cured at high humidity And the phenomenon that the surface is whitened when brought into contact with water after curing. These phenomena are serious drawbacks when used as a coating material or a casting material that requires aesthetic appearance. When the curable composition is used as a paint or an adhesive, it is not always used for indoor work. For example, work related to civil engineering and construction work is often performed under severe outdoor conditions. In addition, the season in which these are adopted is not limited to only when the temperature is warm, and there are cases where the environment is a low temperature environment such as winter or a high humidity environment such as rainy season. These defects are further amplified when the ambient temperature is low or the humidity is high during curing. The reason why the defect is amplified is that the polyamine is affected by acid gas or moisture in the air.

In order to solve this drawback, a prereaction of a polyamine with an epoxide, a cyanoethylation or a derivatization of various polyamines called a Mannich reaction are usually performed. However, although the surface condition of the cured product is somewhat improved by these methods, the effect is not sufficient, and the surface condition is basically affected by the properties of the raw material polyamine. In this regard, the polyamine constituting the curable epoxide-based composition must be less susceptible to the effects of carbon dioxide gas and moisture in the air during the curing process without derivatizing the polyamine as described above. .

[0006]

SUMMARY OF THE INVENTION The present invention employs an amine-based curing agent component having an improved property of providing a cured product having a good surface condition even at a low temperature or in a high humidity environment when the composition is cured. And a polyepoxide composition.

In the present invention, an epoxide, polyepoxide or a mixture thereof having an average of one or more epoxide groups per molecule, and a benzene ring represented by the following general formula (A) may be substituted with an alkyl group. Curable epoxy resin compositions consisting of or containing bis (5-amino-2- (alkoxy) benzene as a main component are included.

Embedded image In the formula, R ₁ and R ₂ independently represent an alkyl group having 1 to 4 carbon atoms, and may be, for example, a methyl group or an ethyl group.

These diamines include 1,3 and 1,4-bis (5-amino-2-methoxypentoxy)
Examples include methylbenzene, 1,3 or 1,4-bis (5-amino-2-methoxypentoxy) ethylbenzene, 1,3 or 1,4-bis (5-amino-2-methoxypentoxy) benzene. . Among them, 1,3 or 1,4-bis (5-amino-2-methoxypentoxy)
Benzene (hereinafter BAMPB) is particularly preferred.

The polyepoxide used in the present invention is
The following equations (E ₁ ), (E ₂ ) and (E ₃ )

Embedded image And a compound having one or more glycidyl groups in the molecule whose skeleton is represented by the following.

Catechol, resorcinol, hydroquinone, biphenol, bis (hydroxyphenyl) alkane, novolak or resol of phenol or alkylphenol, novolak or resol of phenol and cyclopentadiene, novolak or resol of alkylphenol and cyclopentadiene, dioxynaphthalene, Diglycidyl ethers such as novolak or resol of naphthalene and alkyl naphthalene, novolak or resol of phenol and naphthalene, novolak or resol of alkylphenol and naphthalene, triglycidyl ether ester of hydroxybenzoic acid,
Reaction of glycidyl esters of isophthalic acid, terephthalic acid, dicarboxyalkanes, polymerized fatty acids, glycidylated products of benzylamine and alkylbenzylamine, triglycidylated compounds of aminophenol, tetraglycidylated compounds of diamines, reaction of phenol with aniline and formaldehyde , Polyglycidyl compounds such as reaction products of alkylphenols with aniline and formaldehyde, di- or polyglycidyl ethers such as dihydroxycyclohexane, bis (hydroxycyclohexyl) alkane, alkylene glycol, polyoxyalkylene glycol, trimethylolpropane, glycerin, pentaerythritol And a reaction product of a polyoxyalkylene glycol and an isocyanate with a bisphenol. Among these, bis (hydroxyphenyl) alkane diglucidyl ethers such as bisphenol A, bisphenol F and bisphenol AD are particularly preferred.

Although it cannot be the main component of the polyepoxide or the polyepoxide component, a small amount of a monoepoxide compound may be present as a viscosity adjusting component.
These include alkyl glycidyl ethers such as butyl glycidyl ether and hexyl glycidyl ether; phenyl glycidyl ether; m- or p-tolyl glycidyl ether; Glycidyl esters and the like can be listed.

As these epoxides and polyepoxides, a single epoxide and a single polyepoxide, or a single polyepoxide can be used, respectively.
Also, epoxide mixtures, polyepoxide mixtures,
Alternatively, a mixture thereof can be used.

The polyepoxide-based curable composition of the present invention may be substituted with an alkyl-substituted bis (5-amino-
Although 2- (alkoxy) pentoxy) benzene is used as a main part of the curing agent component, various amines or polyamines conventionally known can be used in combination. The following can be shown as examples of these.

Fatty amines such as propylamine, butylamine, pentylamine, hexylamine, octylamine, laurylamine, caprylamine, myristylamine, octylamine, stearylamine, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, Pentaethylenehexamine, propylenediamine, dipropylenetriamine, diaminobutane, diaminopentane, hexamethylenediamine, diaminodecane, diaminododecane, trimethylhexamethylenediamine, methylpentamethylenediamine, piperazine, aminoethylpiperazine, dimethylaminopropylamine, diethylaminopropyl Amine, dipropylaminopropylamine, dibutylaminopropylamine, Aliphatic polyamines such as methylaminoethylamine, diethylaminoethylamine, dipropylaminoethylamine, dibutylaminoethylamine, cyclohexylamine, alkylcyclohexylamine, diaminocyclohexane, xylylenediamine, 1,3-bis (aminomethyl) cyclohexylamine, isophorone Diamine, tricyclodecanediamine, bis (aminomethyl) bicyclo [2,2,1] heptane, 5,5′-methylenebis-2-furanomethanediamine, spiroacetal ring-containing diamine, mensandiamine, bis (aminocyclohexyl) methane , Screws (3
-Methyl-4-aminocyclohexyl) ring-containing diamines such as methane, polyoxyethylenediamine or triamine, polyoxypropylenediamine or triamine,
Polyoxyalkylenediamine or triamine such as polyoxytetramethylenediamine or triamine, and further, aniline, alkylaniline, phenylenediamine, diethyltoluenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenylether, 1,1′-bis [4- (P-aminophenoxy) phenyl] cyclohexane, aromatic monoamines such as aniline / benzene / formaldehyde oligomers, diamines or polyamines.

The epoxide curable composition of the present invention includes:
Solvents as workability improvers usually used in this field,
A curing accelerator as various reactivity improvers and a plasticizer as a cured product performance improver can be used in combination. These examples are as follows.

Alkyl benzenes such as toluene and xylene, monoalcohols such as methanol, propanol, butanol, pentanol, hexanol, cyclohexyl alcohol, benzyl alcohol and tetrahydrofurfuryl alcohol, ethylene glycol, propylene glycol, butylene glycol and the like Polyalcohols, ketones such as methyl isobutyl ketone and cyclohexanone, amide compounds such as formamide and dimethylformamide, tertiary amines such as dimethylaminomethylphenol and tris (dimethylaminomethyl) phenol, and monophenols such as phenol and alkylphenol , Bisphenols such as bisphenol A, bisphenol F, bisphenol S, phenol or alkyl Oligomers from phenol-formaldehyde, alkylcarboxylic acids, benzoic acid, salicylic acid, carboxylic acids such as paratoluenesulfonic acid or metal salts thereof, fatty acid and phthalic acid alkyl esters, sulfonic acid, alkylsulfonic acid, Amides and the like.

The polyepoxide-based curable composition of the present invention can be used in various fields such as adhesives, paints, fillers, casting agents, and laminating agents. In these application fields, in consideration of various performance improvements, aesthetic improvements, economic efficiency, and the like, usually, various other components are often mixed,
The same can be applied to the curable composition of the present invention. The following can be listed as the components in such a case.

Dyes and pigments for coloring purposes, extenders for pursuing economic efficiency and improving performance, synthetic resins and various additives for the same purpose.

Next, the present invention will be described in more detail with reference to examples.

[0020]

EXAMPLES The polyepoxides used in this example are commercially available and are specifically as follows. (1) Epoxide A: Bisphenol A manufactured by Asahi Ciba
Diglycidyl ether: Araldite AER-26
0, epoxide equivalent about 190. (2) Epoxide B: glycidyl ether of bisphenol F, a product of Dainippon Ink and Chemicals, Epolite 830;
Epoxide equivalent weight of about 175. (3) Epoxide C: Diglycidyl ether of Mitsui Petrochemical Industries Petroleum Bisphenol AD: Epomic R-71
0, epoxide equivalent about 173.

The comparative diamine used in this example is as follows. (1) Diethylenetriamine (DETA): Tosoh product, molecular weight 103. (2) Meta-xylylenediamine (MXDA): Mitsubishi Gas Chemical, molecular weight 136. (3) Isophorone diamine (IPDA): a product of Huels, molecular weight 170.
(4) Polyoxypropylene diamine (POPDA):
Texaco Chemical Jeffamine D-230, molecular weight about 230.

The test method adopted in the examples is as follows. Curing drying test : In a polyethylene cup, epoxide and diamine are weighed in stoichiometric amounts and mixed well. This is applied to a predetermined glass plate so as to have a dry film thickness of about 100 μm. This was observed for finger touch time (D ₁ ), half-curing time (D ₂ ) and curing time (D ₃ ) using an RCI type curing and drying tester. Surface condition test : Similarly, a mixture of polyepoxide and diamine is applied to a predetermined glass plate so as to have a dry film thickness of about 100 μm. This was left to cure in a thermo-hygrostat set under certain conditions, and the gloss, smoothness and tackiness of the coating film were observed. Evaluation E (excellent), G
The determination of (good) and P (bad) was made by the observer's observation or by touching with a finger. Water drop test : Under the environment of the set temperature and humidity, after the coating film applied on the glass plate was cured, water drops were adhered, and the degree of whitening after standing for a certain time was observed. The evaluation was judged by the observer.

Examples 1 to 3 The above polyepoxide and BAMPB were mixed in stoichiometric amounts. About these things, temperature 23 ° C, humidity 50%
The cured state and the surface state of the coating film were observed under the standard conditions of the above. Table 1 shows the results. The surface condition of each cured coating film was E (excellent).

Examples 4 to 6 Epoxide A and BAMPB were similarly mixed in a stoichiometric amount, and the cured product was observed in an environment at a temperature of 35 ° C. and a humidity of 80% to observe the surface condition of the coating film. went. Table 2 shows the results. The surface condition of the cured coating film is E (excellent)
Met.

Examples 7-9 Epoxide A and BAMPB were similarly mixed in stoichiometric amounts, and the cured products were observed in an environment of a temperature of 23 ° C. and a humidity of 80% to observe the surface condition of the coating film. went. Table 3 shows the results. The surface condition of the cured coating film is E (excellent)
Met.

Examples 10 to 12 Epoxide A and BAMPB were similarly mixed in a stoichiometric amount, and the cured product was observed in an environment at a temperature of 10 ° C. and a humidity of 80% to observe the surface condition of the coating film. went. Table 4 shows the results. The surface condition of the cured coating film was E (excellent) except for the tackiness.

Comparative Examples 1-4 Epoxide A and a commercially available diamine were mixed in a stoichiometric amount, and the cured and dried test and the observation of the surface condition of the coating film were conducted at a temperature of 23 ° C. and a humidity of 50%. went. Table 1 also shows the results. The surface condition is clearly inferior to that of Example 1.

Comparative Examples 5 to 7 Epoxide A and a commercially available diamine were mixed in a stoichiometric amount, and the resulting mixture was subjected to a curing / drying test at a temperature of 35.degree. The surface condition was observed. Table 2 shows the results. Unlike Example 4, none of the items of the surface condition test and the water drop test were excellent.

Comparative Examples 8 to 10 Epoxide A and a commercially available diamine were mixed in a stoichiometric amount. The surface condition was observed. Table 3 shows the results. Unlike Example 7, none of the items of the surface condition test and the water drop test were excellent.

Comparative Examples 11 to 13 Epoxide A and a commercially available diamine were mixed in a stoichiometric amount. The surface condition was observed. Table 4 shows the results. Unlike Example 10, all the surface condition test items other than the adhesiveness were poor.

[0031]

According to the above description, the bis (5-
A polyepoxide-based curable composition using (amino-2-methoxypentoxy) alkylbenzene as a curing agent component has an excellent surface state when it is made into a cured product, and is particularly improved at the time of curing at low temperature or under high humidity conditions. It is evident that it exhibits an effect, as a result of which it is extremely useful to apply it industrially and can be deployed in a wide range of applications.

[0032]

[Table 1]

[Table 2]

[Table 3]

[Table 4]

Claims (3)

[Claims] 1. An epoxide, a polyepoxide or a mixture thereof having an average of one or more epoxide groups per molecule, and a compound represented by the following general formula (A): [In the formula, R ₁ and R ₂ represent an alkyl group having 1 to 4 carbon atoms. A polyepoxide-based curable composition comprising bis (5-amino-2- (alkoxy) pentoxy) benzene in which the benzene ring represented by the formula ( ₁ ) may be substituted with R1, or containing these as a main component. 2. The method according to claim 1, wherein the bis (5-amino-2-alkoxypentoxy) benzene is 1,3-bis (5-amino-2-alkoxypentoxy) benzene.
The polyepoxide-based curable composition according to claim 1, which is (methoxypentoxy) benzene. 3. A method for producing a polyepoxide-based cured product using the composition according to claim 1, comprising reacting the epoxide component of the composition according to claim 1 with the amine component.