JP2993605B1 - Aqueous solution of epoxy resin - Google Patents

Abstract

An object of the present invention is to provide a completely novel water-soluble epoxy resin soluble in water, an aqueous solution of an epoxy resin, and a method for producing the same. A water-soluble epoxy resin, a cured product thereof, and a powder of a cured product, wherein the epoxy resin comprises a reaction product or a polymer of an epoxy compound and an amine compound represented by the formula (1). NH ₂ N (R ¹ ) (R ² ) (1) [R ¹ and R ² are the same or different and are alkyl having 1 to 6 carbons, alkylene having 2 to 11 carbons when both are bonded or-
And a group represented by R ³ —N (R ⁴ ) —R ⁵ —. R ³ , R ⁵
Is the same or different and is an alkylene having 1 to 6 carbon atoms, and R ⁴ is an alkyl or amino group having 1 to 6 carbon atoms. ]

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to aqueous solutions and a method of manufacturing the same d epoxy resin. Conventionally, it is considered that an epoxy resin does not dissolve in water, and in that sense, the aqueous solution of the epoxy resin of the present invention is completely novel contrary to the conventional common sense.

[0002] Epoxy resins have excellent electrical insulation, moisture resistance, heat resistance, solder resistance, chemical resistance, durability, adhesiveness, mechanical strength and the like.
In various fields such as electricity, electronics and civil engineering, sealing materials,
Widely used as paints, adhesives, etc.

[0003]

2. Description of the Related Art Conventionally, curing of an epoxy resin is carried out by adding a curing agent to the epoxy resin and heating the epoxy resin. Typical curing agents here include, for example, diethylenetriamine, triethylenetetramine, isophoronediamine, diaminodiphenylmethane, diaminodiphenylsulfone, polyamides, dicyandiamide, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, novolak Phenolic resins, tertiary amines, imidazoles, and boron trifluoride amine complexes.

[0004]

Although those cured with these curing agents can be dissolved in organic solvents, those dissolved in water have not been known.

An object of the present invention is to provide a totally novel soluble in water, an aqueous solution of d epoxy resin and a manufacturing method thereof.

[0006]

SUMMARY OF THE INVENTION The present invention provides an aqueous solution of an epoxy resin comprising a reaction product or polymer of an epoxy compound and an amine compound represented by the formula (1), and its production.
According to the method . NH ₂ N (R ¹ ) (R ² ) (1) [R ¹ and R ² are the same or different and each have an alkyl having 1 to 6 carbons, an alkylene having 2 to 11 carbons when both are bonded or-
^{R 3 -N (R 4) -R} 5 - represents a group represented by the. R ³ ,
R ⁵ is the same or different and is an alkylene having 1 to 6 carbon atoms;
⁴ represents an alkyl or amino group having 1 to 6 carbon atoms. ]

The aqueous solution of the epoxy resin of the present invention is, for example, an epoxy compound or an organic solvent solution thereof and a compound of the formula (1)
Mixing the amine compound or an aqueous solution thereof, reacting or polymerizing the epoxy compound and the amine compound, adding water to the obtained epoxy resin solution and heating,
It can be obtained by distilling and removing the organic solvent, water and unreacted amine compound.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy compound applicable to the present invention is not particularly limited, and may be a conventionally known epoxy compound. Examples thereof include glycidyl ether type epoxy resins, glycidyl ester type resins, glycidylamine type epoxy resins, and the like.

Glycidyl ether type epoxy resins include bisphenol A type, bisphenol F type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol S type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type and phenol novolak type. ,
Cresol novolak type, DPP novolak type, trifunctional type, tris / hydroxyphenylmethane type, tetraphenylolethane type and the like can be mentioned.

Examples of the glycidyl ester resin include a phthalic ester type and a hexahydrophthalic ester type.

Examples of the glycidylamine type epoxy resin include tetraglycidyldiaminodiphenylmethane, triglycidylisocyanurate, hydantoin type, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, aminophenol type, aniline type and toluidine type. Can be mentioned.

In R ¹ and R ² of the amine compound of the formula (1) of the present invention, examples of the alkyl having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, isopropyl, isobutyl, n-butyl and t-butyl. , S-butyl, n-pentyl, isopentyl, t-pentyl, neopentyl,
Examples thereof include n-hexyl and isohexyl.
Examples of the alkylene having 2 to 11 carbon atoms formed by combining both R ¹ and R ² include ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, decamethylene,
Undecamethylene and the like can be mentioned.

Further, both R ¹ and R ² are formed by bonding.
The group represented by R ³ —N (R ⁴ ) —R ⁵ — includes, for example, — (CH ₂ ) ₂ —N (CH ₃ ) — (CH ₂ ) ₂ —— (CH ₂ ) ₂ —N (NH ₂ ) - (CH _{2) 2} - and the like. As the alkylene having 1 to 6 carbon atoms for R ³ and R ⁵ , and the alkyl having 1 to 6 carbon atoms for R ⁴ , the same groups as described above can be exemplified.

In the present invention, the amine compound is NH
_The 2NR ¹ R ² type is suitable for the purpose of the present invention, and a water-soluble epoxy resin cannot be obtained with amine compounds other than this type. The amine compound is a known compound, for example, 1-aminopyrrolidine (NR-1), 1-aminohomopiperidine (AHP), 1,1-dimethylhydrazine (UDMH), N-amino-N′-methylpiperazine (AMPI) and the like.

The proportion of the epoxy resin of the present invention used in the production of the epoxy compound and the amine compound is usually 0.5 to 2.0, preferably 1 to 1.8 in equivalent ratio (epoxy / amine). It is good to be about.

The aqueous solution of the epoxy resin of the present invention is prepared by, for example, mixing the above-mentioned epoxy compound or its organic solvent solution with the amine compound of the formula (1) or its aqueous solution, and reacting or polymerizing the epoxy compound and the amine compound. Then, water is added to the obtained epoxy resin solution and heated to distill and remove the organic solvent and unreacted amine compound.

Examples of the organic solvent include solvents capable of dissolving epoxy compounds other than ketones, aldehydes, esters, and halogens, such as aromatic hydrocarbons such as toluene and xylene, and tetrahydrofuran. Can be. Among them, it is preferable to use a mixed solvent of one or two or more of these solvents and alcohols such as methanol, ethanol, and isopropyl alcohol.
The ratio is preferably about 95% by volume, preferably 50 to 90% by volume. The concentration of the epoxy compound in the organic solvent can be appropriately set depending on the type of the solvent and the type of the epoxy compound and the concentration of the amine compound to be reacted.
5 to 100% by weight in terms of solid content, preferably 30 to 80%
% By weight is preferred. If the concentration is too high, an irreversible curing reaction may occur, and a water-soluble resin may not be obtained. If the concentration is too low, the production efficiency decreases, which is not preferable.

The concentration of the amine compound in the aqueous solution of the amine compound is usually about 10 to 100% by weight, preferably 30 to 90% by weight. The concentration of the epoxy compound and the amine compound is set so that if one of them is set to a high concentration, the other concentration is restricted, and the solid content of the target product in the reaction solution is 30 to 80% by weight. Is good.

The reaction or polymerization of the epoxy compound and the amine compound preferably proceeds at a temperature of usually from 10 ° C. to 40 ° C., particularly preferably at a temperature from room temperature to about 30 ° C. The reaction is usually completed in about 30 minutes to 10 hours, but is preferably performed for 1 hour or more for aging. The reaction product contains an organic solvent, unreacted amine compound, and the like, but since the amine compound impairs the stability over time of the water-soluble epoxy resin of the present invention, it is necessary to purify and remove these compounds. preferable.

Examples of the purification method include a method in which an organic solvent and a residual amine compound are distilled off by evaporation while adding water. The amount of water to be added at this time may be appropriately added so that the epoxy resin concentration in the epoxy resin solution is maintained at approximately less than 60% in terms of solid content. The water-soluble epoxy resin of the present invention has a solid content of 10%.
It can be used as a ６０60% aqueous solution. Alternatively, the solid matter once dried and dehydrated may be pulverized and used as a powder.

Although the structure of the water-soluble epoxy resin of the present invention and the mechanism showing water solubility are not yet clear, for example, the water-soluble epoxy resin of the present invention produced from bisphenol A type epoxy resin and 1-aminopyrrolidine has the following formula ( It is considered to have a structure as in 2) or formula (3). n
Is usually about 1 to 20.

[0022]

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[0023]

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The aqueous solution of the epoxy resin of the present invention may contain, if necessary, a conventionally used curing agent or curing accelerator as long as the preferable properties are not impaired. As the curing agent, diethylenetriamine, triethylenetetramine, isophoronediamine, diaminodiphenylmethane, diaminodiphenylsulfone, polyamides, dicyandiamide, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, methylnadic anhydride, novolak phenol described in the prior art Resins, tertiary amines, imidazoles, amine complexes of boron trifluoride, melamine, methylolmelamine, resole type compounds and the like can be mentioned.

Examples of the curing accelerator include tri-n-butylamine, benzylmethylamine, 2,4,6
Tertiary amines such as tris (dimethylaminomethyl) phenol, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-
And imidazoles such as phenylimidazole.

If necessary, the epoxy resin aqueous solution of the present invention may contain inorganic fillers, reinforcing materials, and the like which have been conventionally added to epoxy resins. Known inorganic fillers can be used, for example, silica, fused quartz, calcium carbonate, barium carbonate, barium sulfate, hydrated alumina, alumina, magnesia hydrate, zircon, cordierite, silicon nitride, boron nitride, nitrided Aluminum and the like can be given. Known reinforcing materials can be used, for example, inorganic materials such as glass chops, asbestos, talc, and mica, and glass fibers, potassium titanate fibers, titanium dioxide fibers, wollastonite, zonotolite, and inorganic materials such as zinc silicate fibers. Fibers and the like can be mentioned. The filler, and the type of the reinforcing material, purity, by appropriately changing the amount added, the thermal conductivity of the cured product obtained,
It is known that crack resistance, electrical properties, tracking resistance, and the like can be adjusted.
The filler and the reinforcing material are added in an amount of about 20 to 160 parts by weight, preferably about 50 to 120 parts by weight based on parts by weight. The filler and the reinforcing material may be used alone or in combination of two or more.

Further, the epoxy resin to which the epoxy resin curing agent of the present invention is applied may optionally contain an additive conventionally used as an epoxy resin additive. Examples of such additives include inorganic pigments (particulate titanium dioxide, carbon black, red iron oxide, yellow iron oxide, etc.), organic pigments, viscosity modifiers, leveling agents,
Examples include an antifoaming agent, a coupling agent, a plasticizer, a diluent, a flame retardant, and an organic solvent.

The aqueous solution of the epoxy resin of the present invention is, for example,
The present invention can be applied to articles of various shapes composed of at least one of various materials such as metals, synthetic resins, cements, ceramics, fibers, and papers. Specifically, articles of various shapes may be immersed in the epoxy resin composition of the present invention or coated or coated with the epoxy resin composition of the present invention on the surface of the article, and then left as it is and cured. In the case of heating, the conditions such as temperature and the like are determined by various conditions such as the type of epoxy resin, the type of curing agent, and the type and amount of compounding when adding other additives, and the use of the obtained epoxy resin cured product. The temperature may be appropriately selected depending on the case, but may be generally set to about 20 to 250 ° C.

Further, the epoxy resin composition of the present invention is formed into a molded article having an arbitrary shape in accordance with a usual molding method such as cast molding, and the molded article is bonded to articles of various shapes composed of at least one kind of various materials. It can also be attached according to a normal method such as fitting. The curing conditions at the time of molding may be the same as those for coating or impregnation.

[0030]

The present invention will be described more specifically with reference to the following examples. Example 1 38 g of a bisphenol A type epoxy resin (trade name “Epicoat 828”, epoxy equivalent 190, manufactured by Yuka Shell Epoxy Co., Ltd.) was dissolved in a mixed solvent of 20 ml of methanol and 5 ml of tetrahydrofuran, and 60% of 1-aminopyrrolidine ( NR-1) The solution was added to 14.3 g of an aqueous solution and reacted. The temperature in the system at the time of addition was maintained at 20 to 30 ° C, and the reaction was continued for 1 hour while maintaining the temperature in the reaction system at 20 to 30 ° C to obtain the water-soluble epoxy resin of the present invention. The water-soluble epoxy resin thus obtained was distilled off unreacted amine compounds, organic solvents, etc. while adding water using an evaporator, and a pale yellow viscous water-soluble epoxy resin aqueous solution (solid content 40%) was obtained.
%). This was thinly coated on a glass plate using a doctor blade and allowed to stand at room temperature for 12 hours, whereupon it was solidified to form an epoxy resin film.

Example 2 30.6 g of a phenol novolak type epoxy resin (trade name "Epikote 152", epoxy equivalent: 175, manufactured by Yuka Shell Epoxy Co., Ltd.) was dissolved in a mixed solvent of 20 ml of methanol and 10 ml of tetrahydrofuran, and dissolved in 60%. Of 1
4.3 g of an aminopyrrolidine aqueous solution was added and reacted. The temperature in the system at the time of addition was maintained at 20 to 30 ° C, and the reaction was continued for 1 hour while maintaining the temperature in the reaction system at 20 to 30 ° C.
The water-soluble epoxy resin of the present invention was obtained. The obtained water-soluble epoxy resin is distilled off unreacted amine compounds, organic solvents, etc. while adding water using an evaporator to obtain a pale yellow viscous water-soluble epoxy resin aqueous solution (solid content 40%). Was.

Example 3 In place of 1-aminopyrrolidine (NR-1), 1-aminohomopiperidine (AHP), 1,1-dimethylhydrazine (UDMH) and N-amino-N'-methylpiperazine (AMPI) were used. A water-soluble epoxy resin was produced in the same manner as in Example 1 except for using the same. After vacuum drying this in a desiccator, the residue was poured into water and the water solubility was visually checked. As a result, water solubility was observed in each case.

[0033]

According to the present invention, it is possible to provide a completely novel water-soluble epoxy resin soluble in water, an aqueous solution of an epoxy resin, and a method for producing the same.

Continued on the front page (72) Inventor Akihiro Nabeshima 463 Kagasuno, Kawauchi-cho, Tokushima City, Tokushima Prefecture Inside the Tokushima Plant of Otsuka Chemical Co., Ltd. In the factory (56) References JP-A-5-112632 (JP, A) JP-A-9-110966 (JP, A) JP-A-10-45736 (JP, A) (58) Fields investigated (Int. . ^6, DB name) C08G 59/50 - 59/60 C08G 59/14

Claims (5)

(57) [Claims] An aqueous solution of an epoxy resin comprising a reaction product or a polymer of an epoxy compound and an amine compound represented by the formula (1). NH ₂ N (R ¹ ) (R ² ) (1) [R ¹ and R ² are the same or different and each have an alkyl having 1 to 6 carbons, an alkylene having 2 to 11 carbons when both are bonded or-
^{R 3 -N (R 4) -R} 5 - represents a group represented by the. R ³ ,
R ⁵ is the same or different and is an alkylene having 1 to 6 carbon atoms;
⁴ represents an alkyl or amino group having 1 to 6 carbon atoms. ] 2. The aqueous solution according to claim 1, wherein the epoxy compound is a bisphenol A type epoxy resin. 3. The aqueous solution according to claim 1, wherein the amine compound is 1-aminopyrrolidine. 4. The aqueous solution according to claim 1, wherein the ratio between the epoxy compound and the amine compound is 0.5 to 2.0 in equivalent ratio (epoxy / amine). 5. An epoxy compound or an organic solvent solution thereof and an amine compound of the formula (1) or an aqueous solution thereof are mixed, and the epoxy compound and the amine compound are reacted or polymerized. A method for producing an aqueous solution of an epoxy resin, which comprises adding water and heating to distill and remove an organic solvent and an unreacted amine compound to obtain an aqueous solution of an epoxy resin.