JPS6231004B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel epoxy-modified nitrogen-containing compound that has multiple double bonds in its molecule, can be deposited on a cathode by electrodeposition, and has self-curing properties. A coating method in which paint is deposited on the surface of the object by electrophoresis using the object to be coated as an electrode is generally called electrodeposition coating.The electrodeposition coating method, which is widely used for car body painting, uses the object to be coated as an anode. There are two types of electrodeposition methods: anionic electrodeposition methods that use the coated object as a cathode, and cationic electrodeposition methods that use the object to be coated as a cathode. Among these, the latter cationic electrodeposition method uses the metal of the object to be coated as a cathode, and therefore has the great advantages of no elution of metal ions and better throwing power than anionic electrodeposition methods. As a result of our efforts to develop new materials for cationic electrodeposition, the present inventors have discovered a novel nitrogen-containing epoxy compound represented by the following structural formula (A). [ _Wherein , represents one selected from the group, and n is an integer from 2 to 6. (i) (In the formula, Y represents hydrogen or bromine, p is 0
An integer between 30 and 30. ) (ii) (In the formula, R ₂ is hydrogen or a methyl group, q is an integer from 1 to 15, and has the relationship q = n-1.) (iii) (In the formula, R ₃ represents hydrogen or a methyl group,
t is an integer from 1 to 10. ) In the above structural formula (A), X is the structural formula described in (i)
Those represented by (B) are preferred, and Y is preferably hydrogen. Further, in the above structural formula (A), there is no restriction on the relative positions of the two substituents substituted on the benzene nucleus, but it is preferable that they are substituted at the p-position from the viewpoint of ease of raw material synthesis. The epoxy-modified nitrogen-containing compound represented by the above structural formula (A) is composed of a monomer represented by the following structural formula (E) and the following ~
is obtained by reacting a polyepoxy compound selected from the group of polyepoxy compounds. (R ₁ has the same meaning as above.) (In the formula, Y and p represent the same meanings as above.) (In the formula, R ₂ and q have the same meanings as above.) (In the formula, R ₃ and t have the same meanings as above.) The monomer (E) is an amine represented by the following structural formula (S), and the corresponding alkali metal amide (T).
It is obtained by reacting with divinylbenzene in the coexistence of.

【formula】

[Formula] (In the formula, R ₁ represents the same meaning as above, and M represents an alkali metal.) As the alkali metal, lithium is preferable from the viewpoint of reactivity and the like. As divinylbenzene, crude divinylbenzene containing p-divinylbenzene, m-divinylbenzene, and ethylvinylbenzene as impurities can be used, and among these, p-divinylbenzene is particularly preferred. As the amine, a primary amine or a secondary amine can be used, but methylamine and ammonia have low reactivity and are not preferred. Primary amines include ethylamine, n-propylamine, isopropylamine, n-butylamine,
Primary amines having a hydrocarbon group, such as alkylamines such as sec-butylamine, tert-butylamine, pentylamine, and 2-ethylhexylamine, cycloalkylamines such as cyclohexylamine and cyclopentylamine, and unsaturated amines such as allylamine and benzylamine. can be mentioned. In this reaction, an alkali metal amide such as lithium amide acts as a catalyst. Therefore, for example, it is sufficient to use lithium amide in an equimolar amount or less relative to divinylbenzene, preferably 0.001
twice the mole to 0.5 times the mole, more preferably 0.01
It is twice the mole to 0.2 times the mole. Since lithium amide is deactivated by reacting with water, alcohol, etc., it is preferable that the raw materials and solvents used be purified in advance. Lithium amide can be easily prepared by reacting an alkyllithium such as n-butyllithium with an amine. Amine (S) causes a stoichiometric reaction with divinylbenzene, and the amount used is preferably 0.3 to 2.5 times, and more preferably 0.6 to 1.3 times, in molar ratio to divinylbenzene. One method for reacting a mixture of lithium amide and an amine with divinylbenzene is to add the former mixture to divinylbenzene,
Another method is to add divinylbenzene to a mixture of lithium amide and amine. This reaction is preferably carried out in the presence of an inert solvent. Examples of solvents include aliphatic hydrocarbons such as pentane, hexane, and cyclohexane, aromatic hydrocarbons such as benzene and toluene, and ethers such as diethyl ether, dioxane, and tetrahydrofuran.
Liquids that do not react with lithium amide under the reaction conditions can be used, such as aprotic polar solvents such as dimethyl sulfoxide and N,N'-dimethylformamide. The amount of solvent used is preferably 0.1 to 50 times the volume of divinylbenzene, more preferably 0.5 times the volume of divinylbenzene.
A volume of 2 to 20 times is preferred. There are no particular restrictions on the reaction temperature, but between -50°C and 100°C.
℃ is preferable, and -20℃ to 50℃ is more preferable. To stop the reaction, alcohol such as methanol, ethanol, propanol, or water may be added to deactivate the lithium compound. Next, the above polyepoxy compounds will be explained. A compound represented by the structural formula (F) in which Y is hydrogen is a typical example of an epoxy resin called bisphenol A diglycidyl ether. Preferred examples included in this group are tetrachlorobisphenol A diglycidyl ether and tetrapromobisphenol A diglycidyl ether. As representative examples of the compound represented by the structural formula (G), phenol novolac epoxy resin, O-cresol novolac glycidyl ether, etc. are preferable. Examples of compounds represented by structure (J) include ethylene glycol diglycidyl ether,
Propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether,
1,4-butylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, diglycidyl ether and the like are preferred. The preparation of the compounds disclosed in this invention is based on the structural formula (E)
This is achieved by reacting the monomer shown in (1) with the above polyepoxy compound. The amount of monomer (E) is preferably 0.2 to 4 times the epoxy group of the polyepoxy compound, and 0.5
More preferably, it is twice to twice the molar amount. There is no limit to the reaction temperature, but it is preferably 0°C or higher and 200°C or lower, and 40°C or higher and 200°C or lower.
More preferably, the temperature is between 120°C and 120°C. This reaction is accelerated by adding small amounts of water, alcohol, or acid. The alcohol is preferably an aliphatic alcohol having 1 to 12 carbon atoms such as methanol, ethanol, n-butanol, propanol, t-butanol, and cyclohexyl alcohol. Examples of acids include aliphatic or aromatic monocarboxylic acids or polycarboxylic acids such as p-toluenesulfonic acid, salicylic acid, formic acid, benzoic acid, lactic acid, oxalic acid, acetic acid, butyric acid, maleic acid, and phthalic acid. It is also preferable to carry out the reaction in a solvent. Particularly when the epoxy compound is solid, the use of a solvent is particularly preferred. Inert solvents are preferred, but alcohols such as ethanol, propanol and butanol, nitriles such as acetonitrile, ethers such as dioxane, ethylene glycol monoethyl ether and diisopropyl ether, nitro compounds such as nitrobenzene and nitropropane, Examples include aromatic hydrocarbons such as toluene and ethylbenzene, and esters such as ethyl acetate and methyl propionate. There is no limit to the amount of the above additives or solvents, but
It is preferably 0.1% to 200% by weight, more preferably 5% to 80% by weight of the reaction raw material. It is also possible to add a polymerization inhibitor such as hydroquinone or di-t-butylcatechol to the reaction system. The reaction product can be used as it is, but it can also be used after being isolated by pouring it into hexane or the like for reprecipitation. The compound represented by structural formula (A) converts into a three-dimensional crosslinked product by self-curing. Curing is the polymerization of all or part of the vinyl groups in the compound represented by structural formula (A),

This is achieved by forming a combination of [Formula]. As a result, the resulting crosslinked product consists of a unit structure represented by the following structural formula (R). (In the formula, x+y=n, n is an integer from 2 to 5, x is an integer from 1 to n,
R ₁ represents the same meaning as above. ) This crosslinking reaction is preferably carried out by electron beam irradiation, heating, or the like. In the former case, the electron beam irradiation dose is preferably from 0.01 Megarad to 10 Megarad, more preferably from 0.2 Megarad to 2 Megarad. In addition, when heated, the temperature is 50℃ to 250℃.
is preferred, and more preferably 100°C to 200°C. Further, curing is accelerated by adding a polymerization initiator or a metal salt of carboxylic acid. As a polymerization initiator, 2,2'-azobisisobutyronitrile, 1,1'-azobiscyclohexane-1-carbonitrile, 2-cyano-2-propylazoformamide, 2-phenylazo-2,4
- Azo compounds such as dimethyl-4-methoxyvaleronitrile, peroxide ketones such as methyl ethyl ketone peroxide and cyclohexanone peroxide, hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide, dit-butyl peroxide, dicumyl peroxide Dialkyl peroxides such as benzoyl peroxide, acetyl peroxide, succinic peroxide, diacyl peroxides such as lauroyl peroxide, peroxy esters such as t-butyl peroxy acetate, t-butyl peroxy isobutyrate, t-butyl peroxy benzoate, etc. etc. When it is necessary to store a solution containing a polymerization initiator in a composition for a long time, it is recommended to use a high-temperature decomposition type polymerization initiator. In addition, as a metal salt of carboxylic acid, carbon number 1
Metal salts of 30 to 30 fatty acids, for example metal salts of naphthenic acid, particularly salts of cobalt, lead, manganese, calcium, aluminum, zinc, zirconium, copper, iron, etc. are preferred, and cerium octylate and the like can also be used. There is no limit to the amount of these polymerization initiators and carboxylic acid metal salts added, but it is 0.01% by weight of the composition.
Preferably 10% to 10%, more preferably 0.1% to 5%
% is preferred. The compositions of the present invention and crosslinked products thereof are particularly useful as coatings. The coating method involves dissolving this composition in a suitable solvent,
It is also possible to apply it and evaporate the solvent, but
Most preferred is the cationic electrodeposition method. The cationic electrodeposition method involves reacting this composition with acid HA, dissolving or dispersing it in water, using this as an electrolyte, using the object to be coated as a cathode, and passing a direct current between it and the counter electrode. The composition is deposited on the coated object. There are no particular restrictions on acid HA, but examples include hydrochloric acid, sulfuric acid, nitric acid, chromic acid, perchloric acid, phosphoric acid, minerals such as carbonic acid, acetic acid, propionic acid, butyric acid,
Aliphatic carboxylic acids such as caproic acid, hydroxycarboxylic acids such as glycolic acid and lactic acid, malonic acid,
Dicarboxylic acids such as adipic acid, aromatic carboxylic acids such as benzoic acid, phthalic acid, and salicylic acid, alkanesulfonic acids such as methanesulfonic acid and ethanesulfonic acid, and arylsulfonic acids such as benzenesulfonic acid, toluenesulfonic acid, and laurylbenzenesulfonic acid. Among these, organic carboxylic acids are preferred, and acetic acid, lactic acid, hydroxyacetic acid, and the like are more preferred because they can keep the electrolyte near neutrality. The amount of acid added is preferably 0.1 to 5 times the amount of basic nitrogen in the composition, more preferably 0.3 to 2 times the amount by mole. When acid HA is added to the compound (A) disclosed in the present invention, it is converted into a structure represented by the following structural formula (A)'. (In the formula, ztw=n, and X and R ₁ have the same meanings as described above.) In this operation, the composition can also be used in a form dissolved in a solvent. This solvent will be a mixture of those already mentioned in the explanation of each component of the composition,
The concentration of solids in the solution is preferably between 50% and 95%.
%, more preferably 60% to 90%. The amount of water used to prepare the electrolyte is
It is preferably equal to or more than 30 times the weight of the present composition,
More preferably, it is 5 times or more and 20 times or less. It is desirable to add water gradually while stirring the composition-acid mixture. When performing electrodeposition, important properties of the electrolytic solution include the pH and specific conductivity of the solution. PH is preferably 3 to 8, more preferably 5 to 7.
PH is controlled by the type and amount of acid used for neutralization. Also, the specific conductivity is 200 to 5000μmho/cm
is preferable, more preferably 500 to 3000μmho/cm
It is. Typical examples of the material of the cathode, that is, the surface to be coated, include zinc phosphate treated steel plates, iron phosphate treated steel plates, untreated steel plates, galvanized steel plates, tin plated steel plates, aluminum, copper, and copper alloys. As an anode,
Stainless steel plates, carbon plates, etc. are preferred. There is no limit to the voltage between the electrodes, but 50V to 500V is preferred, and 100V to 400V is particularly preferred. The electrodeposition time is preferably 10 seconds to 20 minutes, more preferably 1 minute to 10 minutes. The temperature of the electrodeposition solution is 0℃ to 60℃
The temperature is preferably 10°C to 40°C, more preferably 10°C to 40°C. The composition of the present invention may be used with a pigment added thereto. Examples of pigments include red iron oxide, titanium white, carbon black, talc, clay, iron oxide, lead oxide, strontium chromate, barium sulfate, cadmium yellow, cadmium red, and chrome yellow. A coating film formed by dissolving the composition in a solvent and applying it and then removing the solvent or by cationic electrodeposition functions as a coating film in its original form, but it cannot be converted into a three-dimensional crosslinked product. Accordingly, a better coating film can be obtained. There are no restrictions on the method of curing the coating film, but a preferred method is heating. The heating temperature is preferably 100°C to 250°C, more preferably 150°C or more and 220°C or less. The coating film thus obtained exhibited good chemical resistance, strength, flexibility, and weather resistance. In particular, it showed remarkable performance in resistance to salt spray. Moreover, a molded article can be obtained by placing the composition of the present invention in a mold and causing a crosslinking reaction by heating or the like. Examples will be described below, but the present invention is not limited thereto. Note that reference examples are also shown. Reference Example 1 Prepare a stirring device, a thermometer, and a reflux device in a three-necked flask 2 purged with nitrogen, and add 44 ml of purified tetrahydrofuran using a dropping funnel. While stirring, 86 ml of isopropylamine was added, followed by 20 ml of a 2N solution of n-butyllithium, and the color of the solution changed from clear and colorless to pale yellow. This flask was placed in a constant temperature bath at 30°C, and 148 ml of p-divinylbenzene was added while stirring. The reaction mixture is orange and remains
After reacting for an hour, 1 ml of methanol was added, and the mixture was poured into 2 water. Extraction was performed twice with n-hexane, the oil layer was dried over magnesium sulfate overnight, and then distilled. 0.07mm as product
11.8g of a fraction having a boiling point of around 67°C in Hg was obtained.
This product is p-(isopropylaminoethyl)
It was confirmed that it was styrene from the following spectrum data. Proton nuclear magnetic resonance spectrum (100MHz, solvent: deuterated chloroform, reference material TMS), δ value;
0.8 (1H), 0.96 (double line, J=7Hz, 1H), 2.6~
2.9 (multiplet, 5H), 5.1 (double line, J=11Hz,
1H), 5.6 (doublet, J=18Hz, 1H), 6.6 (two sets of doublets, 1H), 7.0-7.35 (multiplet, 4H). Infrared absorption spectrum (liquid film); 3300, 1630,
1510, 1470, 1380, 1080, 990, 910, 835 cm ^-1 . Reference example 2 After putting 80 ml of n-hexane that has been dried and distilled over sodium metal into a stainless steel pressure-resistant reaction device with an internal volume of 200 ml and equipped with a stirring device, the device is sufficiently cooled from the outside with a dry ice-methanol mixture. Did. An ethylamine cylinder (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was connected to the apparatus, and the valve was opened to introduce ethylamine into the reaction apparatus. From the change in the weight of the cylinder before and after introduction, it was confirmed that 6.3g of ethylamine had been introduced. While stirring, 8.4 ml of a 15% n-hexane solution of n-butyllithium was introduced. Next, 18.2g in 40ml of dry n-hexane
A solution containing p-divinylbenzene was introduced. The reactor was placed in a water bath at 25° C., and stirring was continued for 5 hours. 0.5 g of methanol was added to the reaction mixture, and the mixture was poured into 200 ml of water. Extraction was performed twice with n-hexane, the oil layer was dried over magnesium sulfate overnight, and then distilled. 72℃ at 0.31mmHg
14.7g of a fraction having a boiling point of 73°C was obtained. It was confirmed by gas chromatography that it was a single substance. The refractive index of this fraction is 1.538 (Na
D line). The spectroscopic analysis results were as follows. Infrared absorption spectrum; 3280, 1620, 1510,
1120, 985, 900, 820 cm ^-1 . Nuclear magnetic resonance spectrum [100MHz, tetramethylsilane (TMS) standard], δ value: 0.80 (singlet,
1H), 1.04 (triple line, J = 7.2Hz, 3H), 2.55 (4
Multiplet, J=7.2Hz, 2H), 2.6-2.8 (multiplet,
4H), 5.08 (double line, J = 10.5Hz, 1H), 5.60 (2
double line, J=17.8Hz, 1H), 6.56 (two sets of double lines,
J=10.5, 17.8Hz, 1H), 6.9-7.3 (multiplet,
4H). Here, J is a coupling constant, and nH is equivalent to n hydrogen atoms. These analytical results indicate that the product is para-(β-ethylaminoethyl)styrene. Example 1 A bisphenol A diglycidyl ether type epoxy resin (AER-661 manufactured by Asahi Kasei Corporation; epoxy equivalent: 450~
500) was taken, 66.4 g of ethylene glycol monoethyl ether was added thereto as a solvent, the temperature was raised to 80°C, and the mixture was stirred and dissolved. After AER-661 was dissolved, the temperature was lowered to 60°C, and 65.6 g of p-isopropylaminoethylstyrene was added as a monomer and stirring was continued. The reaction temperature and reaction time were 60°C for 1 hour, 80°C for 2.5 hours, and 90°C for 1.5 hours to complete the reaction. The completion of the reaction was confirmed by gas chromatography, and the end point was determined by the disappearance of p-isopropylaminoethylstyrene (this reaction solution was referred to as C-1). When a portion of this reaction solution was poured into cold hexane, a white precipitate was generated. This was separated and dried under vacuum. The elemental analysis values of the obtained product were as follows. C: 77.6%, H: 8.2%, N: 2.3%,
O: 12.7% Also, the infrared absorption spectrum gave the following absorption. 3480, 1630, 1610, 1520, 990,
910 cm ^-1 . In addition, put 150 g of the above reaction solution into flask 2, and add 13.5 g of neutralizing acid while stirring well.
After gradually adding 72% lactic acid, 1,
Add 4g of 1'-azobiscyclohexane-1-carbonitrile and add another 840ml while stirring.
of deionized water was added to obtain a cloudy white liquid. PH of this liquid
was measured to be 6.0 and specific conductivity to be 3200 μmho/cm. Add a zinc phosphate treated steel plate (manufactured by Nippon Test Piece Co., Ltd., 150m/m x 70m/m x 0.8m/
m), and a direct current was passed for 3 minutes at a voltage of 250 V using the stainless steel plate as an anode. During this time, the electrolyte solution continued to be magnetically stirred, and the temperature of the electrolyte solution was 28°C to 32°C. A uniform white coating film was formed on the steel plate. After thoroughly washing the coated plate with water, it was air-dried and heated at 175°C for 20 minutes, resulting in a uniform, glossy coating. When the physical properties of the paint film were evaluated, the Erichsen value was 7.6 m/m, and in the Dupont impact test, no peeling cracks were observed in the paint film even when a load of 1 kg was dropped from a height of 50 cm. In addition, the pencil hardness was 3H, and the goban test was 100/100. Examples 2 to 10 Synthesis of the compound of the present invention, preparation of electrodeposition solution, electrodeposition, baking, and coating film evaluation were carried out in the same manner as in Example 1. Table 1 shows the raw materials used in the synthesis of the compounds, the preparation composition of the electrodeposition solution, and the physical properties of the coating film, and Table 2 shows the elemental analysis values of each compound. All coatings passed the DuPont impact test under the conditions of 1 kg x 50 cm, and the goblin test was also 100/100.

【table】

【table】

【table】

[Table] Example 11 1,1'- to 150g of C-1 obtained in Example 1
3 g of azobisisobutyronitrile was mixed, placed in a mold, and heated at 100° C. for 3 hours to obtain a molded product.

Claims (1)

[Claims] 1. A novel epoxy-modified nitrogen-containing compound represented by the following structural formula (A). [ _Wherein , represents one selected from the group, and n is an integer from 2 to 6. (i) (In the formula, Y represents hydrogen or bromine, p is 0
An integer between 8 and 8. ) (ii) (In the formula, R ₂ is hydrogen or a methyl group, q is an integer from 1 to 5, and has the relationship q = n-1.) (iii) (In the formula, R ₃ represents hydrogen or a methyl group,
t is an integer from 1 to 10. )〕