JP2955311B2 - Resin composition for coating - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a coating resin composition. In particular, the present invention is excellent in corrosion resistance, water resistance, solubility in organic solvents,
The present invention also relates to a coating resin composition having excellent mechanical properties such as adhesion and flexibility.

(Prior art) Conventionally, dihydric phenols, especially 2,
A low molecular weight epoxy resin obtained from 2-bis (4-hydroxyphenyl) propane (hereinafter referred to as bisphenol A) and epichlorohydrin is further reacted with a dihydric phenol to obtain a high molecular weight epoxy resin, which contains a polyisocyanate group. A compound in which a compound is compounded as a curing agent is generally used.

However, it is known that polyols based on the high molecular weight epoxy resin have excellent physical properties,
Insufficient solubility in organic solvents, poor compatibility with bituminous substances and / or substitutes in general, and cured products are extremely hard and have poor flexibility. There were wide restrictions.

In order to improve such disadvantages of the above high molecular weight epoxy resin, a high molecular weight epoxy resin obtained by reacting a dihydric phenol with a glycidyl ether compound of an alkylene oxide adduct of a dihydric phenol is further reacted with an epoxy group. A polyether polyol resin obtained by reacting a compound having a group having
No.-7457). Also, a polyhydric alcohol obtained by reacting a glycidyl ether of a polyhydric alcohol, a glycidyl ether of a polyhydric phenol, and an epoxy resin obtained by reacting a polyhydric phenol with a compound having a group reactive with an epoxy group. An ether polyol resin was considered (JP-A-63-95218). However, these polyether polyol resins have a serious drawback in that the inherent corrosion resistance of the epoxy resin is lost.

(Problem to be Solved by the Invention) An object of the present invention is to provide a coating resin composition which solves the above-mentioned problems.

(Means for solving the problem) In view of such a situation, the present inventors have made intensive efforts. As a result, the use of lithium hydroxide as a reaction catalyst for a high molecular weight epoxy resin has resulted in a partial cross-linking structure in the resin skeleton. To form
Further, by reacting a polyhydric alcohol alone or a mixture with a polyhydric phenol, the solubility in organic solvents, the compatibility with bituminous substances and / or substitutes thereof, and the corrosion resistance while maintaining the flexibility of the cured product are maintained. Greatly improved,
Furthermore, they have found that the curability at low temperatures can be improved by reacting a primary or secondary amine compound alone or as a mixture, thereby completing the present invention.

That is, the present invention provides an epoxy group of a high molecular weight epoxy resin (a-1) obtained by reacting a substituted or unsubstituted glycidyl ether of a polyhydric phenol with a polyhydric alcohol alone or a mixture of the polyhydric phenol with lithium hydroxide as a catalyst. One equivalent or two or more monovalent hydroxyl group-containing compounds or one or two or more monovalent carboxyl group-containing compounds are added in an amount of 0.50 to 0.98 equivalents, and one or two or more primary or secondary amine compounds are added in an amount of 0.50 to 1.0 equivalent. The present invention relates to a resin composition for coating characterized by containing a polyether polyol resin (a) obtained by reacting -0.02 equivalents and a polyvalent isocyanate compound (b).

Examples of the substituted or unsubstituted glycidyl ether of polyhydric phenol include those represented by the general formula (I).

_{EO-R 2 -O-E '} n O-R 2 -O-E (I) ( wherein, E is And R ₁ represents a hydrogen atom or a lower alkyl group.

R ₂ And the above-mentioned nucleus-substituted compounds and halides. R _{3 -CH 2 -, - C -,} - O -, - S -, - SO -, - SO 2 - represents a.

R ₁ , R ₂ and R ₃ may be the same or different. n is the number of repeating units and 0 ≦ n ≦ 7. Examples of the substituted or unsubstituted glycidyl ether of the polyhydric phenol represented by the general formula (I) include Epicoat 828, # 1001, # 1004 (manufactured by Yuka Shell Epoxy Co., Ltd.), Epototo YD128 (Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin such as Epicron 850 (Dai Nippon Ink Co., Ltd.), Epicoat 807 (Yuka Shell Epoxy Co., Ltd.), Epicron 830 (Dai Nippon Ink Co., Ltd.), Araldite XPY306 (Ciba Geigy) Bisphenol F type epoxy resin, such as bisphenol F type epoxy resin such as Denacol EX-251 (manufactured by Nagase Kasei Kogyo Co., Ltd.), bisphenol type epoxy resin, biphenyl type epoxy resin, and novolak type epoxy resin , Cresol novolak type epoxy resin, resol type epoxy resin and the above-mentioned epoxy resin Examples thereof include a nucleus-substituted product such as a methyl group of a xy resin and a halide.

Examples of the polyhydric alcohol which is reacted with the substituted or unsubstituted glycidyl ether of these polyhydric phenols include ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, butanediol, polytetramethylene glycol, hexanediol, and polyhexamethylene glycol. And polyhydric alcohols such as neopentyl glycol, trimethylolpropane, pentaerythritol, glycerin and hydrogenated bisphenol A, and propylene oxide adducts of polyhydric phenols.

The polyhydric phenol used as a mixture with a polyhydric alcohol if necessary has at least one aromatic nucleus in the molecule and is substituted with two or more hydroxyl groups in the aromatic nucleus. Good examples include mononuclear polyhydric phenols and polynuclear polyhydric phenols.

The amount of polyhydric phenol used is 0.5 equivalent or less per equivalent of glycidyl ether of polyhydric alcohol.

Examples of such mononuclear polyphenols include resorcinol, hydroquinone, pyrocatechol, phloroglicinol, 1,5-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene.

Examples of the polynuclear polyphenols include 2,2-bis (p-hydroxyphenyl) propane, 2,4'-dihydroxydiphenylmethane, bis (2-hydroxyphenyl) methane, and bis (4
-Hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1,2-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxy-2-
Chlorophenyl) ethane, 1,1-bis (3,5-dimethyl-
4-hydroxyphenyl) ethane, 1,3-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, 2,2-bis (3 -Phenyl-4-hydroxyphenyl) propane, 2,2-bis (3-isopropyl-4-hydroxyphenyl) propane, 2,2-bis (2-isopropyl-4-hydroxyphenyl) propane, 2,2-bis ( 4-hydroxynaphthyl) propane, 2,2-bis (4-hydroxyphenyl) pentane, 3,3-bis (hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) heptane, 2,2-bis ( Bis (hydroxyphenyl) alkanes such as 4-hydroxyphenyl) -1-phenylpropane, or 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 2,4 -
Dihydroxybiphenyl, such as dihydroxybiphenyl, or bis (4-hydroxyphenyl) sulfone;
4'-dihydroxydiphenyl sulfone, chloro-2,4 '
-Dihydroxydiphenylsulfone, 3-chloro-2,
Di (hydroxydiphenyl) sulfone, such as 4'-dihydroxydiphenylsulfone, 3'-chloro-2,4'-dihydroxydiphenylsulfone, or bis (4-hydroxyphenyl) ether, 4,3 '-(or 4, 2'- or 2,2'-dihydroxy-diphenyl) ether, 4,4 '
-Dihydroxy-2,6-dimethyldiphenyl ether,
Includes di (hydroxyphenyl) ethers such as bis (4-hydroxy-3-isobutylphenyl) ether, and 1,1-bis (4-hydroxyphenyl) -2-phenylethane, 1,3,3,- Trimethyl-1- (4-hydroxyphenyl) -6-hydroxyindane and 2,4-bis (p-hydroxyphenyl) -4-methylpentane are also suitable.

Examples of the monovalent hydroxyl group-containing compound include phenolic hydroxyl group-containing compounds such as phenol, xylenol, t-butylphenol, and p-cumylphenol. Examples of the alcoholic hydroxyl group include methanol,
Ethanol, isopropyl alcohol, n- (or sec
-Or t-) butanol, octanol and the like.

Examples of the monovalent carboxyl group-containing compound include benzoic acid, propionic acid, and lactic acid.

Examples of the primary or secondary amine compound include methylamine, ethylamine, butylamine, and propylamine as the primary amine, and dibutylamine and the like as the secondary amine. Of these, N-alkyl is preferable. Examples of amines include ethanolamine, propanolamine, diethanolamine, diisopropanolamine, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine, N-isopropylethanolamine, N-butylethanolamine, and N-methylpropanol. Amine, N-ethylpropanolamine, N-propylpropanolamine, N-
Isopropylpropanolamine, N-butylpropanolamine, N-methylisopropylanolamine, N
-Ethylisopropanolamine, N-propylisopropanolamine, N-isopropylisopropanolamine, N-butylisopropanolamine and the like.

 The specific conditions of the above reaction are described below.

The reaction of a substituted or unsubstituted glycidyl ether of a polyhydric phenol with a mixture of a polyhydric alcohol alone or with a polyhydric phenol is carried out in the presence of a lithium hydroxide catalyst at 60 to 25.
It is carried out at a temperature of 0 ° C, preferably 120-200 ° C. If the reaction temperature is lower than 60 ° C, the reaction rate becomes too low, which is not preferable.If the reaction temperature exceeds 250 ° C, ring-opening reaction with hydroxyl groups in the epoxy resin or ring-opening reaction between epoxy groups occurs. This is not preferable because the reaction product may be gelled.

The amount of catalyst used depends on the reaction temperature, but usually
0.01 to 10000 ppm, preferably 0.
1-1000 ppm is used. The epoxy equivalent of the obtained high molecular weight epoxy resin (a-1) is preferably from 500 to 600 g / equivalent, and particularly preferably from 1,000 to 4,500 g / equivalent.

When sodium hydroxide, potassium hydroxide or tertiary amines, which are generally used, are used in place of lithium hydroxide as a catalyst, the reaction is very slow and the desired high molecular weight epoxy resin (a-1) cannot be obtained. .

Next, a monovalent hydroxyl group-containing compound or 1 equivalent of the epoxy group of the high molecular weight epoxy resin (a-1) was used.
One or more active hydrogens of the monovalent carboxyl group-containing compound are reacted in an amount of 0.50 to 0.98 equivalent.

The reaction is carried out at a temperature of 60 to 250 ° C, preferably 120 to 200 ° C. If the reaction is less than 60 ° C., the reaction rate becomes too low, which is not preferable.If the reaction temperature exceeds 250 ° C., a ring-opening reaction with a hydroxyl group in the epoxy resin or a ring-opening reaction between epoxy groups occurs. It is not preferable because the reaction product may be gelled. The use of a catalyst is not particularly necessary, but when the reaction is slow, 0.01 to
There is no problem in using 10,000 ppm, preferably 0.1 to 1000 ppm.

Furthermore, the epoxy group 1 of the high molecular weight epoxy resin (a-1)
The active hydrogen of the primary or secondary amine compound alone or in a mixture is reacted with 0.50 to 0.02 equivalent to the equivalent.

The reaction is carried out at a temperature of 40 to 200 ° C, preferably 90 to 130 ° C. A catalyst is not particularly required, but does not prevent its use if the reaction is slow. The hydroxyl equivalent of the obtained polyether polyol resin (a) is preferably from 40 to 400 KOH mg / g, particularly preferably from 80 to 300 KOH mg / g.

The reaction can be carried out without using a solvent, but when a solvent is used, hydrocarbons such as toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, ketones such as cyclohexanone, n-butyl acetate,
Solvents having no active hydrogen such as acetic esters such as methoxybutyl acetate and cellosolve acetate are used.

The polyvalent isocyanate compound (b) used in the present invention includes, for example, toluene diisocyanate, xylylene diisocyanate, crude diphenylmethane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate methyl ester, and 3 moles of toluene diisocyanate adduct of trimethylolpropane and the like. And the resulting high molecular weight polyisocyanate (prepolymer).

The compounding ratio of the polyvalent isocyanate compound (b) is such that the compounding ratio of the hydroxyl group equivalent to the isocyanate equivalent in the polyether polyol resin is 0.4 to 1.2, preferably 0.6 to 1.0. Since the composition comprising the polyether polyol resin of the present invention and the polyvalent isocyanate compound (b) is curable at room temperature (drying property), it should be used immediately after preparation.

The composition obtained in this manner is sufficiently useful as a coating agent by itself, but is used in combination with a bituminous substance or a substitute for a bituminous substance for the purpose of further improving corrosion resistance and the like.

As the bituminous substance, coal tar, coal tar pitch, various cut pack tars, swollen carbonaceous materials, asphalt and the like can be used.

Various alternatives to bituminous substances include, for example, aromatic oil resins, coumarone resins, petroleum resins and DOP, DBP, and other petroleum and coal-based high boiling points commonly used as diluents. Neutral oil and the like can be used. The mixing ratio of the bituminous substance and / or the substitute for the bituminous substance is suitably 0.5 to 2 times the weight of the polyether polyol resin.

Incidentally, various curing catalysts, fillers, diluents, dehydrating agents, resins and the like can be added to the composition of the present invention as needed.

(Examples) Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

(1) Production of polyether polyol resin Production example of polyether polyol resin (A) 1000.0 g of Epicoat # 1001 (epoxy equivalent: 450), 50.0 g of bisphenol A, polypropylene glycol in a flask equipped with a stirrer, thermometer and cooling tube (Molecular weight about 40
0) After adding 250.0 g and lithium hydroxide as a catalyst,
The inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring.
The epoxy equivalent of the obtained high molecular weight epoxy resin is 2450
g / equivalent. Then add 43.6 g of phenol and add another 175
After reaction at 5 ° C. for 5 hours, the mixture was cooled to 100 ° C., and 6.5 g of N-methylethanolamine was added. The obtained polyether polyol resin (A) has a hydroxyl equivalent of 125 KOHmg / g.
Met.

Production Example of Polyether Polyol Resin (B) 1000.0 g of Epicoat # 1001 (epoxy equivalent 450), 50.0 g of bisphenol A, polypropylene glycol (molecular weight of about 40
0) After adding 250.0 g and lithium hydroxide as a catalyst,
The inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring.
The epoxy equivalent of the obtained high molecular weight epoxy resin is 2485
g / equivalent. Then, 96.2 g of p-cumylphenol was added, and the mixture was further reacted at 175 ° C. for 5 hours. After cooling to 100 ° C., 6.5 g of N-ethanolamine was added, and the mixture was reacted at 110 ° C. for 6 hours, and diluted with toluene to a solid content of 60%. . The obtained polyether polyol resin (B) has a hydroxyl equivalent of 100 KOHmg.
/ g.

Production example of polyether polyol resin (C) In a flask equipped with a stirrer, a thermometer and a condenser, 1000 g of Epicoat # 1001 (epoxy equivalent: 450), 50.0 g of bisphenol A, polypropylene glycol (molecular weight: about 400) 2
After adding 50.0 g and lithium hydroxide as a catalyst, the inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring. The epoxy equivalent of the obtained high molecular weight epoxy resin was 2480 g / equivalent. Then, 62.6 g of salicylic acid was added, and the mixture was further reacted at 175 ° C. for 5 hours. After cooling to 100 ° C., 6.5 g of N-methylethanolamine was added, and the mixture was diluted with toluene, which was reacted at 110 ° C. for 6 hours, to 60% solids. The obtained polyether polyol resin (C) had a hydroxyl equivalent of 140 KOHmg / g.

Example of production of polyether polyol resin (D) In a flask equipped with a stirrer, thermometer and cooling tube, 1000 g of Epicoat # 1001 (epoxy equivalent: 450), 50.0 g of bisphenol A, 10PN of bisol (bisphenol A with propylene oxide added , Hydroxyl value about 146KOHmg / g)
After adding 500.0 g and lithium hydroxide as a catalyst, the inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring. The epoxy equivalent of the obtained high molecular weight epoxy resin was 3150 g / equivalent. Then, 38.7 g of phenol was added and the mixture was further reacted at 175 ° C. for 5 hours. After cooling to 100 ° C., 5.5 g of N-methylethanolamine was added, and the mixture was reacted at 110 ° C. for 6 hours and diluted with toluene to a solid content of 60%. The obtained polyether polyol resin (D) had a hydroxyl equivalent of 115 KOHmg / g.

Production Example of Polyether Polyol Resin (E) In a flask equipped with a stirrer, thermometer and cooling tube, epicoat # 828 (epoxy equivalent: 188) 1000 g, bisphenol A 100.0 g, polypropylene glycol (molecular weight about 700)
After adding 950.0 g and lithium hydroxide as a catalyst, the inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring. The epoxy equivalent of the obtained high molecular weight epoxy resin was 1190 g / equivalent. Then add 138.0 g of phenol and further add 175 ° C
After cooling to 100 ° C., 19.5 g of N-methylethanolamine was added, and the mixture was reacted at 110 ° C. for 6 hours and diluted with toluene to a solid content of 60%. The obtained polyether polyol resin (E) had a hydroxyl equivalent of 105 KOHmg / g.

Production Example of Polyether Polyol Resin (F) In a flask equipped with a stirrer, a thermometer and a cooling tube, 1000 g of Epicoat # 1001 (epoxy equivalent: 450), 50.0 g of bisphenol A, polypropylene glycol (molecular weight: about 400) 6
After adding 00.0 g and lithium hydroxide as a catalyst, the inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring. The epoxy equivalent of the obtained high molecular weight epoxy resin was 2490 g / equivalent. Then, phenol (50.0 g) was added, and the mixture was further reacted at 175 ° C. for 5 hours and diluted with toluene to a solid content of 60%. The obtained epoxy polyol resin (F) has a hydroxyl equivalent of
It was 115 KOHmg / g.

Production Example of Polyether Polyol Resin (G) In a flask equipped with a stirrer, a thermometer and a condenser, 1000 g of Epicoat # 1001 (epoxy equivalent: 450), 50.0 g of bisphenol A, polypropylene glycol (molecular weight: about 400) 2
After adding 50.0 g and lithium hydroxide as a catalyst, the inside of the system was replaced with nitrogen gas. Subsequently, the system was heated in an oil bath and reacted at a reaction temperature of 175 ° C. for 10 hours with stirring. The epoxy equivalent of the obtained high molecular weight epoxy resin was 2510 g / equivalent. Then, the mixture was cooled to 100 ° C., 40.0 g of N-methylethanolamine was added, and the mixture was reacted at 110 ° C. for 6 hours and diluted with toluene to a solid content of 60%. The obtained epoxy polyol resin (G) had a hydroxyl equivalent of 150 KOHmg / g.

Production example of polyether polyol resin (H) In a flask equipped with a stirrer, a thermometer and a cooling tube, 1000 g of Epicoat # 1001 (epoxy equivalent: 450), 50.0 g of bisphenol A, polypropylene glycol (molecular weight: about 400) 2
After adding 50.0 g and sodium hydroxide as a catalyst, the system was replaced with nitrogen gas. Subsequently, the temperature of the system was raised in an oil bath, and the reaction was carried out at a reaction temperature of 200 ° C. for 50 hours with stirring, but the reaction did not reach the target epoxy equivalent (2450 g / equivalent).

(2) Preparation and Evaluation of Coating Resin Composition Using the polyether polyol resins (A) to (G) obtained in the above Production Examples, coating resin compositions having the compositions shown in Tables 1 and 2 were prepared. Then, they were applied to evaluate them, dried at room temperature for 7 days, and subjected to a coating film physical property test.

The results are shown in Tables 1 and 2.

(Effect of the Invention) The coating obtained by using the coating resin composition of the present invention exhibits excellent corrosion resistance, durability, water resistance, and adhesion.

Various plants, tanks, pipes, ships,
In addition to covering materials for large structures such as bridges, steel frames, vehicles, etc., covering materials for metal products such as household electrical appliances, steam equipment, various measuring instruments, vending machines, medical equipment, floor materials, wall materials, magnetic paints, It is effective for fiber treatment agents, waterproof treatment agents, insulation treatment agents, anti-fog agents for glass, and a wide range of other application fields.

Continuation of front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C09D 1/00-201/10 C08G 18/00-18/87

Claims (1)

(57) [Claims] 1. A general formula _{(I) EO-R 2 -O} -E 'n O-R 2 -O-E (I) ( wherein, E is And R ₁ represents a hydrogen atom or a lower alkyl group. R ₂ And the above-mentioned nucleus-substituted compounds and halides. R _{3 -CH 2 -, - C -,} - O -, - S -, - SO -, - SO 2 - represents a. Further, R ₁ , R ₂ and R ₃ may be the same or different. n is the number of repeating units, and 0 ≦ n ≦ 7. ) And a mixture of a polyhydric alcohol alone or a polyhydric phenol with a mixture of a polyhydric alcohol and lithium hydroxide as a catalyst. One or two or more monovalent carboxyl group-containing compounds
A polyether polyol resin (a) obtained by reacting 0.5 to 0.08 equivalents of one or two or more primary or secondary amine compounds with 0.5 to 0.02 equivalents, and a polyvalent isocyanate compound (b) A resin composition for coating.