JP3285053B2 - New pyrazinium salt compounds and polymerization initiators - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel pyrazinium salt compound and a cationic polymerization initiator containing the same. The cationically polymerizable composition containing the polymerization initiator can be cured in a short time by heating, and the obtained cured product has excellent physical properties, and thus has a molding resin,
It is suitably used as a material for casting resins, paints, adhesives, inks, etc.

[0002]

2. Description of the Related Art Conventionally, active amine-containing compounds, carboxylic anhydrides and mercapto compounds which are widely used in a two-part system as curing agents for epoxy resins. On the other hand, for curing the epoxy resin as a one-part system, there is boron fluoride-monoethylamine. In addition, as the latent heat cationic polymerization initiator and its composition are described,
JP-A-58-37003, JP-A-63-223002
JP-A-56-152833, JP-A-2-1783
No. 19 and JP-A-3-17119 are known.

[0003]

In a so-called two-part system in which an epoxy resin is cured with an active amine-containing compound or a carboxylic anhydride, it is necessary to completely mix the components.
The curing time also takes several hours. In addition, since the reaction occurs sequentially even at room temperature, the pot life is as short as several hours to several days,
There is a handling problem.

On the other hand, a boron fluoride-monoethylamine system which can cure an epoxy resin as a one-part system is convenient in handling, but has a curing temperature of 160 ° C.
As described above, there is a problem that it takes 1 to 8 hours to completely cure. Further, a sulfonium salt-based heat latent cationic polymerization initiator described in JP-A-58-37003 and a pyridinium salt-based heat latent cationic polymerization initiator described in JP-A-2-178319 are disclosed. However, they have a feature that they can be made into a one-part system and have a short curing time, but have a problem that the curing temperature is high.

The present invention has been made in view of the above-mentioned circumstances, and provides a novel cationic polymerization initiator which can cure a cationically polymerizable compound at a low temperature and in a short time by heating. It is an object of the present invention to obtain a storage-stable one-part cationic polymerization composition containing the same and to provide a cured product having excellent physical properties.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies in order to achieve the above object, and found that the use of a polymerization initiator composed of a specific pyrazinium salt compound allows the cationic polymerization to be performed at a low temperature and in a short time. The present invention has been completed by finding a novel polymerization initiator which is capable of curing an active compound and which gives excellent properties of the cured product. That is,
The present invention provides the following general formula 2

[0007]

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[Wherein, R ₁ represents an alkyl group substituted with an aromatic ring or an alkenyl group optionally substituted with an aromatic ring, and R ₂ , R ₃ , R ₄ , and R ₅ each represent a hydrogen atom, Represents an alkyl group, a halogen atom, a nitro group, a cyano group, an alkoxy group, an optionally substituted phenyl group or an alkoxycarbonyl group, wherein R ₂ and R ₃ or R ₄ and R ₅ are each integrally condensed An aromatic ring may be formed, and X
Represents SbF ₆ , AsF ₆ , PF ₆ or BF ₄ ], and a cationic polymerization initiator characterized by containing the compound.

Hereinafter, the present invention will be described in detail. The pyrazinium salt compound of the present invention is represented by the general formula 3,

[0010]

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In the above formula, R ₁ is an alkyl group substituted with an aromatic group such as an optionally substituted benzene ring, an optionally substituted naphthalene ring, an optionally substituted anthracene ring, or a substituted alkyl group. Benzene ring, which may be substituted, a naphthalene ring which may be substituted, a group selected from the group of alkenyl groups which may be substituted with an aromatic ring such as an optionally substituted anthracene ring, for example,
A benzene ring which may be substituted with a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group, a nitro group, a cyano group, a vinyl group, etc., and a benzene ring having a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group A phenethyl group, a naphthalene ring which may be substituted with a nitro group, a cyano group, a vinyl group, etc., is substituted with a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group, a nitro group, a cyano group, a vinyl group, etc. Α-naphthylmethyl group, a β-naphthylmethyl group in which the naphthalene ring may be substituted with a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group, a nitro group, a cyano group, a vinyl group, etc .; Atom, alkyl group, alkoxy group, alkoxycarbonyl group, nitro Group, a cyano group, an α-methylbenzyl group which may be substituted with a vinyl group, etc., and a benzene ring substituted with a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group, a nitro group, a cyano group, a vinyl group, etc. A benzhydryl group, a benzene ring may be substituted with a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group, a nitro group, a cyano group, a cinnamyl group which may be substituted with a vinyl group, etc., and an anthracene ring is a halogen atom or an alkyl group. , An anthracenyl group which may be substituted with an alkoxy group, an alkoxycarbonyl group, a nitro group, a cyano group, a vinyl group, etc., may be substituted in the 3-position with an alkyl group, an alkoxycarbonyl group, an alkoxy group, a halogen atom, etc. A crotyl group and the like can be exemplified.

R ₂ , R ₃ , R ₄ and R ₅ each represent a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group or a t-butyl group, or F, C
a halogen atom such as l, Br, I, a nitro group, a cyano group,
It is a group selected from the group consisting of an alkoxy group such as a methoxy group, an ethoxy group and an isopropoxy group, an optionally substituted phenyl group and an alkoxycarbonyl group such as a methoxycarbonyl group and an ethoxycarbonyl group.

R ₂ and R ₃ or R ₄ and R ₅ may be fused together to form an aromatic ring, for example, a halogen atom, an alkyl group, a nitro group, a cyano group,
A quinoxaline ring or the like which may be substituted with a vinyl group or the like can be formed.

X is SbF ₆ , AsF ₆ , PF ₆ or B
An F _4, the inner, SbF ₆ is used willingly.

The pyrazinium salt compound of the present invention can be obtained, for example, by the following method. 1-halo-3-substituted-2-butene or 1 such as α-substituted benzyl halide such as α-phenethyl bromide and benzhydryl bromide, cinnamyl bromide, crotyl bromide and 1-bromo-3-methyl-2-butene -Bromomethylnaphthalene, halomethylnaphthalene such as 1-bromomethylnaphthalene and pyrazine derivative or quinoxaline derivative are equimolarly mixed at room temperature to 80 ° C in the presence of a solvent such as methanol, acetone or acetonitrile, if necessary. Time to 3
After reacting for 0 days, the obtained solid was dissolved in water or a water-organic solvent system such as a water-methanol system, and sodium hexafluoroantimonate and the like were added and stirred vigorously.
The separated liquid or solid product is separated and dried.

As typical pyrazinium salt compounds of the present invention, the following chemical formulas 4 to 6 can be exemplified. Here, X in the formula represents SbF ₆ , AsF ₆ , PF ₆ or BF ₄ .

[0017]

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[0018]

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[0019]

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In the present invention, the pyrazinium salt compound, which is a polymerization initiator, is used as a cationically polymerizable composition by mixing with a cationically polymerizable compound. Examples of the cationic polymerizable compound include the following compounds. (A) As a compound having an epoxy group, 1,1,3-
Tetradecadiene dioxide, limonenedioxide, 4-vinylcyclohexene dioxide, (3,4
-Epoxycyclohexyl) methyl-3,4-epoxycyclohexylcarboxylate, di (3,4-epoxycyclohexyl) adipate, phenylglycidyl ether, bisphenol A type epoxy resin, halogenated bisphenol A type epoxy resin, o-, m-, Epoxy compounds such as p-cresol novolak type epoxy resin, phenol novolak type epoxy resin and polyglycidyl ether of polyhydric alcohol

(B) As the vinyl compound, styrene, α
Styrenes such as -methylstyrene and p-chloromethylstyrene; alkyl vinyl ethers such as n-butyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether and hydroxybutyl vinyl ether;
Alkenyl vinyl ethers such as allyl vinyl ether and 1-octahydronaphthyl vinyl ether; alkynyl vinyl ethers such as ethynyl vinyl ether and 1-methyl-2-propenyl vinyl ether; aryl vinyl ethers such as phenyl vinyl ether and p-methoxyphenyl vinyl ether; butanediol divinyl ether Divinyl ethers such as triethylene glycol vinyl ether and cyclohexanediol divinyl ether; aralkyl divinyl ethers such as 1,4-benzene dimethanol divinyl ether, Nm-chlorophenyldiethanolamine divinyl ether and m-phenylenebis (ethylene glycol) divinyl ether Vinyl ethers: hydroquinone divinyl ether, resorcinol divinyl ether Aryl divinyl ethers such as ether; N- vinylcarbazole, N- vinylpyrrolidone and cationic polymerizable nitrogen-containing compounds such

(C) As the bicycloorthoester compound, 1-phenyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-
Hydroxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, etc.

(D) As the spiro orthocarbonate compound, 1,5,7,11-tetraoxaspiro [5,
5] undecane, 3,9-dibenzyl-1,5,7,1
1-tetraoxaspiro [5,5] undecane and the like;
4,6-trioxaspiro [4,4] nonane, 2-methyl-1,4,6-trioxaspiro [4,4] nonane,
And spiroorthoester compounds such as 1,4,6-trioxaspiro [4,5] decane.

These may be used alone or in combination of two or more. Among the above (a) to (d), the compound having an epoxy group (a) is particularly preferably used. You.

In the present invention, the mixing ratio of the pyrazinium salt compound to the cationically polymerizable compound is 100 parts by weight of the cationically polymerizable compound and 0.
011 to 20 parts, preferably 0.1 to 10 parts. If the amount of the pyrazinium salt compound is small, the curability of the cationically polymerizable compound decreases, and if it is excessive, the properties of the cured product deteriorate.

The cationic polymerization composition containing the pyrazinium salt compound of the present invention can be easily cured by heating.
In the case of thermosetting, 30 to 200 ° C., preferably 50
Used in the range of ~ 180 ° C.

The cationic polymerization composition containing the pyrazinium salt compound of the present invention contains α-rays, β-rays, γ-rays, neutron rays,
Curing can be easily performed in a short time even with ionizing radiation such as X-rays and accelerated electron beams. In the case of curing by ionizing radiation, a dose in the range of usually 0.5 to 60 Mrad can be used, and a range of 1 to 50 Mrad is preferable. In addition, it is also possible to cure using both ionizing radiation and heat.

The pyrazinium salt compound of the present invention is generally used alone, but can be used in combination with another cationic polymerization initiator. When the compound having an epoxy group of the above (a) is used, the performance of a curing agent such as a phenolic curing agent or an acid anhydride curing agent which is usually used as a curing agent for an epoxy resin is not impaired. May be used in combination.

When the initiator of the present invention is blended with the cationically polymerizable compound and used, a reactive diluent, a curing accelerator, a solvent, a pigment, a dye, a coupling agent,
It is used by adding an inorganic filler, carbon fiber glass fiber, surfactant and the like.

[0030]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples.

Example 1 Synthesis of N-benzylpyrazinium hexafluoroantimonate 10.26 g of benzyl bromide and 4.00 g of pyrazine
And reacted at room temperature for 10 days. The solid obtained was washed with ether and dried under reduced pressure at 40 ° C.
-Benzylpyrazinium bromide was obtained. Yield: 9
2.51 g of 4% N-benzylpyrazinium bromide was dissolved in 15 g of distilled water, 3.10 g of sodium hexafluoroantimonate was added, and the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 92
%

The IR spectrum data of the obtained N-benzylpyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1494, 1445, 115
4,804,755,705,655

Example 2 Synthesis of N-benzyl-2,5-dimethylpyrazinium hexafluoroantimonate 10.26 g of benzyl bromide and 5.41 g of 2,5-dimethylpyrazine were mixed, and the mixture was mixed at 50 ° C. for 3 days. Reacted. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain N-benzyl-2,5-dimethylpyrazinium bromide as a precursor. Yield: 99% 2.79 g of N-benzyl-2,5-dimethylpyrazinium bromide was dissolved in 15 g of distilled water, 3.10 g of sodium hexafluoroantimonate was added, and the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 99%

The IR spectrum data of the obtained N-benzyl-2,5-dimethylpyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1498, 1458, 139
0,1165,1113758,706,660

Example 3 Synthesis of N-benzyl-3-methoxycarbonylpyrazinium hexafluoroanthin timonate 10.26 g of benzyl bromide and 6.91 g of methyl 2-pyrazinecarboxylate were mixed, and the mixture was mixed at 50 ° C. for 3 days. Reacted. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain a precursor N-benzyl-3-methoxycarbonylpyrazinium bromide. Yield: 97% N-benzyl-3-methoxycarbonylpyrazinium bromide (3.09 g) was dissolved in distilled water (15 g), sodium hexafluoroantimonate (3.10 g) was added, and the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 99%

The spectrum data of the obtained N-benzyl-3-methoxycarbonylpyrazinium hexafluoroantimonate IR was as follows. IR (KBr, cm ^-1 ): 1750, 1460, 143
8,1327,1207,1169,772,755,
726,699,657

Example 4 Synthesis of N-benzyl-2,3-dimethylpyrazinium hexafluoroantimonate 5.13 g of benzyl bromide and 3.41 g of 2,5-dimethylpyrazine were mixed, and the mixture was mixed at 50 ° C. for 10 days. Reacted. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain N-benzyl-2,3-dimethylpyrazinium bromide as a precursor. Yield: 93% 2.79 g of N-benzyl-2,3-dimethylpyrazinium bromide was dissolved in 15 g of distilled water, 3.10 g of sodium antimonate hexafluoride was added, and the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 92%

The IR spectrum data of the obtained N-benzyl-2,3-dimethylpyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1499, 1458, 142
9,1387,1163,745,706,660

Example 5 N- (4-nitrobenzyl)
Synthesis of pyrazinium hexafluoroantimonate 10.80 g of 4-nitrobenzyl bromide and 3.20 g of pyrazine were dissolved in 5 g of acetonitrile and reacted at 50 ° C. for 27 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain N- (4-nitrobenzyl) pyrazinium bromide as a precursor. Yield: 94
2.96 g of% N- (4-nitrobenzyl) pyrazinium bromide was dissolved in 15 g of distilled water, and 3.10 g of sodium hexafluoroantimonate was added. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 87%

The IR spectrum data of the obtained N- (4-nitrobenzyl) pyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1526, 1441, 135
1,1168,1145879,811,745,70
3,660

Example 6 Synthesis of N-vinylbenzylpyrazinium hexafluoroantimonate 4.58 g of chloromethylstyrene and 1.60 g of pyrazine
And reacted at 50 ° C. for 7 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C.
-Vinylbenzylpyrazinium chloride was obtained. Yield: 93% 2.33 g of N-vinylbenzylpyrazinium chloride
Was dissolved in a mixed solution of 10 g of distilled water and 5 g of methyl ethyl ketone (hereinafter, referred to as MEK), 3.10 g of sodium hexafluoroantimonate was added, and the mixture was stirred well. To this solution was added 40 g of distilled water, and the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 87%

The IR spectrum data of the obtained N-vinylbenzylpyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1492, 1446, 92
2,805,705,662

Example 7 N- (2-methylbenzyl)
Synthesis of pyrazinium hexafluoroantimonate 5.55 g of 2-methylbenzyl bromide and 1.60 g of pyrazine were mixed and reacted at room temperature for 3 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain N- (2-methylbenzyl) pyrazinium bromide as a precursor. Yield: 98% N- (2-methylbenzyl) pyrazinium bromide (2.65 g) was dissolved in distilled water (15 g), and sodium hexafluoroantimonate (3.10 g) was added. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 93%

The IR spectrum data of the obtained N- (2-methylbenzyl) pyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1495, 1462, 144
0,1386, 1146, 832, 749, 660

Example 8 Synthesis of N-benzhydrylpyrazinium hexafluoroantimonate 12.36 g of benzhydrylbromide and pyrazine
20 g were mixed and reacted at room temperature for 20 days. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain a precursor N-benzhydrylpyrazinium bromide. Yield: 99% N-benzhydrylpyrazinium bromide 3.23 g
Was dissolved in a mixed solvent of 15 g of distilled water and 1 g of methanol, and 3.10 g of sodium hexafluoroantimonate was added.
Stir well. 30 g of distilled water was added to this solution, and the mixture was stirred well and cooled. The precipitated solid is washed with ether,
It dried under reduced pressure at 40 degreeC. Yield: 81%

The IR spectrum data of the obtained N-benzhydrylpyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1496, 1446, 118
7,1151,757,699,657

Example 9 N-benzhydryl-2,5
Synthesis of -dimethylpyrazinium hexafluoroantimonate 7.14 g of benzhydryl bromide and 2.16 g of 2,5-dimethylpyrazine were mixed and reacted at 50 ° C for 2 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain a precursor N-benzhydryl-2,5-dimethylpyrazinium bromide. Yield: 99% 3.15 g of N-benzhydryl-2,5-dimethylpyrazinium bromide was dissolved in a mixed solvent of 5 g of distilled water and 5 g of MEK, and sodium hexafluoroantimonate 3.1 was dissolved.
0 g was added and stirred well. To this solution was added 45 g of distilled water, and the mixture was stirred well and cooled. After removing the supernatant liquid separated into two layers, the residue was dried under reduced pressure at 40 ° C. Yield: 6
5%

IR of the obtained N-benzhydryl-2,5-dimethylpyrazinium hexafluoroantimonate
The spectrum data was as follows. IR (KBr, cm ^-1 ): 1494, 1447, 138
8,1162,755,741,703,660

Example 10 Synthesis of N-cinnamylpyrazinium hexafluoroantimonate 5.91 g of cinnamyl bromide and 1.60 g of pyrazine
And reacted at 50 ° C. for 5 hours. The solid obtained was washed with ether and dried under reduced pressure at 40 ° C.
-Cinnamyl pyrazinium bromide was obtained. yield:
2.77 g of 99% N-cinnamylpyrazinium bromide was dissolved in a mixed solvent of 10 g of distilled water and 4 g of MEK, and 3.10 g of sodium hexafluoroantimonate was added, followed by thorough stirring. To this solution was added 40 g of distilled water, and the mixture was stirred well and cooled. After removing the supernatant liquid separated into two layers, the residue was heated to 40 ° C.
And dried under reduced pressure. Yield: 83%

The spectrum data of the obtained N-cinnamylpyrazinium hexafluoroantimonate of the present invention was as follows. IR (KBr, cm ^-1 ): 1495, 1453, 117
4,974,756,703,663

Example 11 Synthesis of N-cinnamyl-3-methoxycarbonylpyrazinium hexafluoroantimonate 5.91 g of cinnamyl bromide and 2.76 g of methyl 2-pyrazinecarboxylate were dissolved in 6 g of methanol, and the mixture was dissolved at room temperature. The reaction was performed for 5 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain a precursor N-cinnamyl-
3-methoxycarbonylpyrazinium bromide was obtained. Yield: 46% 1.68 g of N-cinnamyl-3-methoxycarbonylpyrazinium bromide was dissolved in a mixed solvent of 15 g of distilled water and 5 g of MEK, and 1.55 g of sodium hexafluoroantimonate was added, followed by thorough stirring. Add 4 parts of distilled water to this solution.
After adding 0 g, the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. Yield: 93%

The resulting N-cinnamyl-3-methoxycarbonylpyrazinium hexafluoroantimonate I
The spectral data of R was as follows. IR (KBr, cm ^-1 ): 1740, 1614, 144
6,1388,1345,1279,963,911
765,693,663

Example 12 N-Cinnamyl-2,5-
Synthesis of dimethylpyrazinium hexafluoroantimonate 5.91 g of cinnamyl bromide and 2.16 g of 2,5-dimethylpyrazine were mixed and reacted at room temperature for 18 hours. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain a precursor N-cinnamyl-2,5-dimethylpyrazinium bromide. Yield: 98% 3.05 g of N-cinnamyl-2,5-dimethylpyrazinium bromide was dissolved in a mixed solvent of 10 g of distilled water and 3 g of MEK, and sodium hexafluoroantimonate 3.10.
g was added and stirred well. To this solution was added 40 g of distilled water, and the mixture was stirred well and cooled. After removing the supernatant liquid separated into two layers, the residue was dried under reduced pressure at 40 ° C. Yield: 86
%

The IR spectrum data of the obtained N-cinnamyl-2,5-dimethylpyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1496, 1452, 138
7, 1184, 1156, 978, 755, 700, 6
61

Example 13 Synthesis of N- (1-naphthylmethyl) pyrazinium hexafluoroantimonate 5.30 g of 1-chloromethylnaphthalene and 1.30 g of pyrazine
60 g were mixed and reacted at 50 ° C. for 3 days. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain N- (1-naphthylmethyl) pyrazinium chloride as a precursor. Yield: 73% N- (1-naphthylmethyl) pyrazinium chloride (2.57 g) was dissolved in distilled water (15 g), and thereto was added 3.10 g of sodium hexafluoroantimonate, and the mixture was stirred well and cooled.
The precipitated solid was dried at 40 ° C. under reduced pressure. Yield: 92
%

The IR spectrum data of the obtained N- (1-naphthylmethyl) pyrazinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1515, 1441, 117
9,1143,795,776,658

Example 14 Synthesis of N- (1-naphthylmethyl) -2,5-dimethylpyrazinium hexafluoroantimonate 5.30 g of chloromethylnaphthalene and 2.16 g of 2,5-dimethylpyrazine were mixed. At 50 ° C. for 8 days. The obtained solid was washed with ether and dried at 40 ° C. under reduced pressure to obtain a precursor N- (1-naphthylmethyl) -2,5.
-Dimethylpyrazinium chloride was obtained. Yield: 5
2.85 g of 2% N- (1-naphthylmethyl) -2,5-dimethylpyrazinium chloride was dissolved in 15 g of distilled water, and 3.10 g of sodium hexafluoroantimonate was added.
Stir well and cool. The precipitated solid was dried at 40 ° C. under reduced pressure. Yield: 99%

The IR spectrum data of the obtained N- (1-naphthylmethyl) -2,5-dimethylpyrazinium hexafluoroantimonate of the present invention was as follows. IR (KBr, cm ^-1 ): 1514, 1469, 138
9,1161,800,780,660

Example 15 Synthesis of N-benzylquinoxalinium hexafluoroantimonate 10.26 g of benzyl bromide and 6.5 of quinoxaline
1 g was mixed and reacted at 50 ° C. for 3 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain a precursor N-benzylquinquinoxalinium bromide.
Yield: 78% 3.10 g of N-benzylquinoxalinium bromide was dissolved in 15 g of distilled water, 3.10 g of sodium antimonate hexafluoride was added, and the mixture was stirred well and cooled. The precipitated compound was separated by filtration and dried at 40 ° C. under reduced pressure. yield:
99%

The IR spectrum data of the obtained N-benzylquinoxalinium hexafluoroantimonate was as follows. IR (KBr, cm ^-1 ): 1515, 1445, 135
9,1224,1163,1074,1016,76
7,726,701,663

<Curability Test> The compounds synthesized in Examples 1 to 15 were dissolved in propylene carbonate,
L-4221 (alicyclic epoxy manufactured by UCC) was added to the epoxy resin to a pure content of 2.5 parts to prepare a blend. A DSC measurement was performed on the blend to determine the top temperature of the peak of the exotherm. The measurement conditions of DSC are as follows, and the measurement results are shown in Table 1. DSC measuring instrument: DSC220C (manufactured by Seiko Denshi Kogyo) Atmosphere: 30 ml / min in a nitrogen gas stream Heating temperature: 10 ° C./min Sample amount: 0.3 to 0.8 mg

[0062]

[Table 1]

Comparative Example 1 As Comparative Sample 1, DSC measurement was carried out in the same manner as in Example, using benzyl-4-cyanopyridinium hexafluoroantimonate as an initiator.

Comparative Example 2 As Comparative Sample 2, N- (α
-Phenethyl) -N, N-dimethyl-N- (2-hydroxyethyl) ammonium hexafluoroantimonate as initiator and ERL-4221 in the same manner as in Examples.
(Alicyclic epoxy manufactured by UCC), and the mixture was adjusted. DSC measurement was performed to determine the top temperature of the peak of heat generation. The results of these measurements are summarized in Table 1 above.

[0065]

As described above, the novel pyrazinium salt compound agent of the present invention is effective as a polymerization initiator for a cationically polymerizable compound. It can be polymerized and cured.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08G 59/68 C08G 59/68 64/00 64/00 C08K 5/3462 C08K 5/3462 5/3465 5/3465 (58) Survey (Int.Cl. ⁷ , DB name) C07D 241/21 C07D 241/16 C07D 241/24 C07D 241/40 C08F 4/00 C08G 59/68 C08G 64/00 C08K 5/3462 C08K 5/3465 CA ( STN) REGISTRY (STN)

Claims (2)

(57) [Claims] 1. A pyrazinium salt compound represented by the following general formula 1. [Wherein, R ₁ represents an alkyl group substituted with an aromatic ring or an alkenyl group optionally substituted with an aromatic ring;
_{R 2, R 3, R 4} , R 5 are each a hydrogen atom, an alkyl group, a halogen atom, a nitro group, a cyano group, an alkoxy group, a phenyl group or substituted represents alkoxycarbonyl group, and R ₂ R ₃ or R ₄ and R ₅ may be fused together to form an aromatic ring;
Represents SbF ₆ , AsF ₆ , PF ₆ or BF ₄ ] 2. A cationic polymerization initiator comprising at least one of the pyrazinium salt compounds according to claim 1.