JPH05140210A - New sulfonium salt compound and polymerization initiator - Google Patents

Abstract

PURPOSE:To cure a cationically polymerizable compound into a product of excellent properties within a short time by heating or irradiation with light or electron beams by using a cationic polymerization initiator comprising a specified sulfonium salt compound. CONSTITUTION:A sulfonium salt compound of the formula (wherein R1 is hydrogen, alkyl or cyano; R2 is phenyl which may be substituted R3 and R4 are the same or different linear or branched alkyl groups and they may be combined with each other; and X is SbF6, AsF6, PF6 or BF4).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel sulfonium salt compound and a cationic polymerization initiator containing the same. The cationically polymerizable composition containing the polymerization initiator and the cationically polymerizable compound can be cured in a short time by heat or radiation such as light and electron beam, and the obtained cured product has excellent physical properties. Therefore, it is suitably used as a material for molding resin, casting resin, paint, adhesive, ink and the like.

[0002]

2. Description of the Related Art Heretofore, epoxy resins include active amine-containing compounds and carboxylic acid anhydrides that are widely used in two-component systems as curing agents. However, in a two-component system using these curing agents, it is necessary to mix each component completely, and the curing time also takes several hours.

On the other hand, there is boron fluoride-monoethylamine for curing an epoxy resin as a one-component system.
It takes 1-8 hours to fully cure at temperatures of 160 ° C. or higher.

In addition, JP-A-50-151976 and JP-A-50-151976.
0-151997, it is known to use phenylsulfonium salts as photocuring agents for epoxies. However, this cures the epoxy resin with light, but the epoxy resin cannot be cured only by applying heat.

On the other hand, JP-A-2-196812 and 3-
17101 describes that a benzylsulfonium salt is used to cure a cationically polymerizable composition by heat or radiation. However, the activity of these initiators is not sufficient for both heat and radiation, and the synthesis method of the polymerization initiator is complicated.

[0006]

The present invention has been made in view of the above-mentioned circumstances, and is a novel cation capable of curing a cationically polymerizable compound by heat or radiation such as light and electron beam in a short time. It is an object of the present invention to provide a cationic polymerization initiator, and further to provide a cured product having excellent physical properties of a cationically polymerizable composition containing the initiator and the cationically polymerizable compound.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in order to achieve the above-mentioned object, and as a result, by using a cationic polymerization initiator composed of a specific sulfonium salt compound, heat, light, electron beam The present invention has been completed by finding out a new cationic polymerization initiator which can be cured in a short time by radiation such as, and which gives the cured product excellent performance.

The present invention has the following general formula [1]:

[0009]

[Chemical 2] [In the formula, R ₁ represents a hydrogen atom, an alkyl group or a cyano group, R ₂ represents an optionally substituted phenyl group, and R 2
₃ and R ₄ are the same or different linear or branched alkyl groups, R ₃ and R ₄ may be bonded together, and X represents SbF ₆ , AsF ₆ , PF ₆ or BF ₄ . ] It is a cationic polymerization initiator characterized by containing at least one sulfonium salt compound represented by the above.

The present invention will be described in detail below. The sulfonium salt compound of the present invention has the general formula [1]

[0011]

[Chemical 3] In the formula, R ₁ is a hydrogen atom, an alkyl group or a cyano group, and the alkyl group is preferably a lower alkyl group such as methyl, ethyl, propyl, isopropyl and butyl. R ₂ is an optionally substituted phenyl group, and as the substituent, a halogen atom such as F, Cl and Br, an alkyl group such as methyl, ethyl, propyl, isopropyl, butyl and methoxy, ethoxy, propoxy,
Examples thereof include alkoxy groups such as isopropoxy and butoxy.
R ₃ and R ₄ are the same or different linear or branched alkyl groups, and the alkyl groups include methyl, ethyl,
Lower alkyl groups such as propyl, isopropyl and butyl are preferably used. In addition, R ₃ and R ₄ may be integrally bonded. X is SbF ₆ , AsF ₆ , PF ₆ or BF ₄ , of which SbF ₆ is preferably used.

The sulfonium salt compound of the present invention can be obtained, for example, by the following method. 3-substituted-1-halogenated-2-butene such as cinnamyl bromide and the corresponding sulfide compound are equimolar at room temperature to 80 ° C. in the presence of a solvent such as methyl alcohol, acetone or acetonitrile, if necessary. After reacting for several hours to 30 days, the obtained solid matter is dissolved in water or a water-organic solvent system such as water-methylethylketone, sodium hexafluoroantimonate is added, and the mixture is vigorously stirred to precipitate a liquid or solid. It is obtained by separating the shaped product and then drying it.

Examples of typical sulfonium salt compounds of the present invention include those represented by the following chemical formulas [2] to [8]. In the formula, X is SbF ₆ , AsF ₆ , PF ₆ or BF ₄ .

[Chemical 4]

[0014]

[Chemical 5]

[0015]

[Chemical 6]

[0016]

[Chemical 7]

[0017]

[Chemical 8]

[0018]

[Chemical 9]

[0019]

[Chemical 10]

The sulfonium salt compound of the present invention is useful as a cationic polymerization initiator and is used in combination with a cationically polymerizable compound. Examples of the cationically polymerizable compound used here include the following compounds. (A) As a compound having an epoxy group, 1,1,3-
Tetradecadiene dioxide, limonene dioxide, 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-, There are epoxy compounds such as p-cresol novolac type epoxy resin, phenol novolac type epoxy resin, and polyglycidyl ether of polyhydric alcohol.

(B) Styrene and α as vinyl compounds
-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 , Alkyldivinyl ethers such as triethylene glycol vinyl ether and cyclohexanediol divinyl ether; aralkyl dialkyl ethers such as 1,4-benzenedimethanol divinyl ether, N-m-chlorophenyldiethanolamine divinyl ether and m-phenylene bis (ethylene glycol) divinyl ether. Vinyl ethers; hydroquinone divinyl ether, resorcinol divinyl ether Aryl divinyl ethers such as ether; N- vinylcarbazole, there is a cationic polymerizable nitrogen-containing compounds such as N- vinylpyrrolidone.

As the (C) 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-1,5,7,11-tetraoxaspiro [5,5] undecane and 1,4,6-trioxaspiro [4,4] nonane, 2-methyl-1,4
6-trioxaspiro [4,4] nonane, 1,4,6-
Examples thereof include spiro orthoester compounds such as trioxaspiro [4,5] decane. These may be used alone or in combination of two or more. Among (a) to (d), the compound having an epoxy group (a) is preferably used.

In the present invention, the mixing ratio of the cationic polymerizable compound and the cationic polymerization initiator is 0.01 to 20 parts by weight, preferably 0.01 to 20 parts by weight, preferably 100 parts by weight of the cationic polymerizable compound. It is compounded in a proportion of 0.1 to 10 parts by weight, and can be easily cured by heat or radiation such as light and electron beam. In the case of curing by heat, the curing temperature is 10 to 200 ° C, preferably 50 to 180 ° C.
The range is. In the case of curing by radiation, light and electron beams are preferably used. Wavelength 400 nm for photo-curing
The following ultraviolet rays are most efficient, and therefore, as the light source, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, a carbon arc lamp, etc. are used. It is also possible to use heat and radiation together to cure. It is also possible to cure it.

The cationic polymerization initiator of the present invention is generally used alone, but may be used in combination with other cationic polymerization initiators.

When the compound (a) having an epoxy group is used, a curing agent such as a phenolic curing agent or an acid anhydride curing agent which is usually used as a curing agent for epoxy resin, and ( When the vinyl compound of b) is used, an organic peroxide or the like as a curing agent for the vinyl compound may be used in combination as long as the performance is not impaired. When the initiator of the present invention is used in combination with the cationically polymerizable compound, a reactive diluent, a curing accelerator, a solvent, a pigment, a dye, a coupling agent, an inorganic filler, a carbon fiber, if necessary. , Glass fiber, surfactant, etc. are used.

[0026]

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

Example 1 <Synthesis of cinnamyldimethylsulfonium hexafluoroantimonate> 9.85 g of cinnamyl bromide and 6.21 g of dimethyl sulfide were mixed and reacted at room temperature for 2 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain a precursor cinnamyldimethylsulfonium bromide. Yield: 74% then cinnamyl dimethyl sulfonium bromide
2.59 g was dissolved in 15 g of distilled water, 3.10 g of sodium hexafluoroantimonate was added, and the mixture was well stirred and cooled. The aqueous solution portion was decanted, washed with ether, then the ether was decanted again and cooled. The solidified compound was filtered off and dried under reduced pressure at 40 ° C. yield :
90%, the obtained cinnamyl dimethylsulfonium hexafluoroantimonate of the present invention has the following structural formula

[9]
Indicated by.

[0028]

[Chemical 11]

The spectral data of this product was as follows. IR (KBr, cm ^-1 ): 1648, 1429, 1248, 979, 75
8, 660, ¹ H-NMR (acetonitrile-d ³ ): δ 2.75 (s,
6H), 4.04 (d, 2H), 6.23 (q, 1H), 6.93
(D, 1H), 7.35 ~ 7.44 (m, 3H), 7.50 ~ 7.55
(M, 2H) ¹³ C-NMR (acetonitrile-d ³ ): 24.1, 45.8,
114.5, 128.2, 129.9, 130.3, 136.2, 143.0

Example 2 <Synthesis of cinnamyl tetramethylene sulfonium hexafluoroantimonate> 9.85 g of cinnamyl bromide
And 8.82 g of tetrahydrothiophene are mixed, and the mixture is mixed at room temperature for 2
The reaction was allowed for 0 days. The obtained solid was washed with ether and dried under reduced pressure at 40 ° C. to obtain a precursor cinnamyltetramethylenesulfonium bromide. Yield: 87% Next, 2.85 g of cinnamyl tetramethylene sulfonium bromide was dissolved in a mixed solvent of 15 g of distilled water and 3 g of methanol to give sodium hexafluoroantimonate 3.10.
g, stirred well and cooled. The solidified compound was filtered off and dried under reduced pressure at 40 ° C. Yield: 98%. The obtained cinnamyl tetramethylene sulfonium hexafluoroantimonate of the present invention is represented by the following structural formula [10].

[0031]

[Chemical 12]

The spectral data of this product was as follows. IR (KBr, cm ^-1 ): 1650, 1493, 1240, 974,
757, 657 ¹ H-NMR (acetonitrile -d ^3): δ 2.16 ~2.
35 (m, 4H), 3.31 to 3.54 (m, 4H), 3.97 (d,
2H), 6.23 (q, 1H), 6.93 (d, 1H), 7.34 ~
7.44 (m, 3H), 7.47 to 7.59 (m, 2H), ¹³ C-NMR (acetonitrile-d ³ ): 29.6, 4
3.2, 45.6, 116.2, 128.1, 129.9, 130.3, 136.3
, 142.1

Examples 3 and 4 <DSC measurement> The compounds (polymerization initiator) synthesized in Examples 1 and 2 were dissolved in propylene carbonate, and ERL-4221 (alicyclic epoxy produced by UCC) and UV were used.
Blending compositions A and B were prepared by adding 2.5 parts as a pure component to 100 parts of each epoxy compound of R-6410 (glycidyl type epoxy manufactured by UCC). DSC measurement was performed on this compounded composition to determine the exothermic onset temperature and D
The top peak temperature of the SC curve was determined. The measurement conditions of DSC are as follows. DSC measuring device: DSC220C (manufactured by Seiko Denshi Kogyo Co., Ltd.) Atmosphere: Nitrogen gas stream 30 ml / min Temperature rising rate: 10 ° C / min Sample amount: 0.3-0.8 mg

COMPARATIVE EXAMPLE 1 Except that benzyldimethylsulfonium hexafluoroantimonate (R-1) was used as a comparative initiator instead of the polymerization initiator which was the compound of the present invention obtained in Examples 1 and 2. DSC measurement was performed in exactly the same manner as in Examples 2 and 3. The results of the DSC measurements of Examples 3 and 4 and Comparative Example 1 are shown in Table 1 above.

[0035]

[Table 1]

[0036]

As described in detail above, the present invention provides a novel sulfonium salt compound, which is effective as a polymerization initiator for a cationically polymerizable compound. Polymerization compositions containing these sulfonium salt compounds, heat and light,
It can be cured in a short time by radiation such as an electron beam.

Claims (2)

[Claims] 1. A general formula [1]: [In the formula, R ₁ represents a hydrogen atom, an alkyl group or a cyano group, R ₂ represents an optionally substituted phenyl group, and R 2
₃ and R ₄ are the same or different linear or branched alkyl groups, R ₃ and R ₄ may be bonded together, and X represents SbF ₆ , AsF ₆ , PF ₆ or BF ₄ . ] The sulfonium salt compound represented by these. 2. A cationic polymerization initiator comprising at least one sulfonium salt compound according to claim 1.