JPH10152469A - Sulfonium salt compound, cationic polymerization initiator and curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject new compound having excellent one-pack storage stability and useful as a cationic polymerization initiator. SOLUTION: The objective compound is expressed by formula I [Ar1 is a (substituted) phenyl or naphthyl; R1 and R2 are each a 1-4C alkyl; Ar2 is a (substituted) phenyl; X is a non-nucleophilic anionic residue], e.g. 3-(4- methoxyphenyl)-2-propylphenylmethylsulfonium hexafluorophosphonate. The compound of the formula I can be produced by reacting a compound of formula II with a compound of the formula R1 -Y, a compound of the formula (R1 O)2 SO2 or a compound of formula III in an organic solvent at room temperature to 100 deg.C for several to several tens hours, adding water and a compound of the formula MX (M is an alkali metal) to the reaction liquid after completing the reaction, stirring the mixture and separating the precipitated compound by filtration or extraction with an organic solvent. A cationic polymerizable compound can be cured at <=100 deg.C by using the objective compound and a cationic polymerization initiator containing the compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sulfonium salt compound, a cationic polymerization initiator containing the compound, and a curable composition containing the cationic polymerization initiator and a cationically polymerizable compound.

[0002]

2. Description of the Related Art When a cationically polymerizable compound such as epoxy is polymerized by heating, various polymerization initiators are added as a catalyst to cure the compound. Sulfonium salt compounds are also known as useful thermosetting catalysts utilizing a cationic reaction. ing. Such sulfonium salt compounds are described in JP-A-2-178303, JP-A-2-178319, JP-A-2-1470, and JP-A-2-1968.
No. 12, JP-A-3-17101, JP-A-3-17101
47164, JP-A-3-59001, JP-A-3-72569, JP-A-3-205405, and JP-A-3-237107.

[0003]

Among the compounds described therein, relatively low curing temperatures, for example 100 ° C.
A sulfonium salt compound that acts as a catalyst below (for example, the compound described in JP-A-2-178303), when stored in a state of being mixed with a polymerizable compound, increases in viscosity from several hours to a few days. Since the one-pack storage stability was poor due to gelation or gelation, it was necessary to mix each time it was used, which was inferior in convenience.

On the other hand, among the compounds described in the above publications, sulfonium salt compounds having excellent one-pack storage stability when mixed with a polymerizable compound (for example, see Japanese Patent Application Laid-Open No.
178319) does not act as a catalyst unless the temperature is 130 ° C. or higher, and may be unsuitable for materials such as plastics which do not have high heat resistance. Further, a cured product obtained by curing a polymerizable compound using these catalysts also has a disadvantage that physical properties such as mechanical strength are poor.

[0005] International Publication WO95 / 24387 exemplifies the following compounds as compounds similar to the compounds of the present invention.

[0006]

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[0007]

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This publication describes that these compounds act as thermosetting catalysts. However, 150 ° C
It only describes its potential as a curing catalyst at moderately high temperatures, but does not describe its curing properties at low temperatures. In fact, these compounds have poor curing properties at low temperatures.

Therefore, there is a need for the development of a sulfonium salt compound which is excellent in one-pack storage stability, but which has high reactivity and can cure a cationically polymerizable compound at a relatively low curing temperature. I have.

An object of the present invention is to provide a sulfonium salt compound capable of curing a cationically polymerizable compound at a temperature of 100 ° C. or lower and having excellent one-pack storage stability when mixed with the polymerizable compound. Is to provide. Another object of the present invention is to provide a polymerization initiator and a polymerizable compound using the same and a curable composition containing the polymerization initiator.

[0011]

Means for Solving the Problems In order to solve the above problems, the invention described in claim 1 of the present invention is a sulfonium salt compound represented by the general formula (I).

[0012]

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(Wherein, Ar ₁ is a phenyl group or a naphthyl group which may be substituted, and R ₁ and R _{2 each} have 1 to 1 carbon atoms.)
4 represents an alkyl group. Ar ₂ represents a phenyl group which may be substituted, and is a phenyl group substituted with at least one of an alkoxy group, a hydroxy group and an alkylcarbonyloxy group. X represents a non-nucleophilic anionic residue. According to a second aspect of the present invention, there is provided a cationic polymerization initiator comprising the sulfonium salt compound according to the first aspect. The invention according to claim 3 is a curable composition comprising a cationically polymerizable compound and the cationic polymerization initiator according to claim 2. According to a fourth aspect of the present invention, in the third aspect, the cationically polymerizable compound is a glycidyl ether type epoxy or an alicyclic epoxy.

When the sulfonium salt compound according to claim 1 and the cationic polymerization initiator according to claim 2 are used, 1
The cationically polymerizable compound can be cured at a temperature of 00 ° C. or lower. Although the curable composition according to claims 3 and 4 contains a cationically polymerizable compound and a cationic polymerization initiator, since the polymerization initiator contains the sulfonium salt compound according to claim 1, It can be stored stably for a long time.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The sulfonium compound of the present invention comprises
It is represented by the general formula (I).

[0016]

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(Wherein, Ar ₁ is a phenyl group or a naphthyl group which may be substituted, and R ₁ and R _{2 each} have 1 to 1 carbon atoms.
4 represents an alkyl group. Ar ₂ represents a phenyl group which may be substituted, and at least one alkoxy group;
It is a phenyl group substituted with a hydroxy group or an alkylcarbonyloxy group. X represents a non-nucleophilic anionic residue. )

The compound of the present invention has an alkyl group as a substituent on a sulfur atom and a carbon atom at the α-position thereof, and Ar ₂
Is a phenyl group having a specific substituent.

In the general formula (I), Ar ₁ represents an alkyl group such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, decyl, dodecyl, fluorine, chlorine , Bromine, halogen atoms such as iodine, hydroxy group, methoxy group, ethoxy group, propoxy group, butoxy group, hexyloxy group,
An alkoxy group such as a decyloxy group and a dodecyloxy group,
A phenyl group or a naphthyl group which may be substituted with an alkylcarbonyl group such as an acetoxy group, a propionyloxy group, a decylcarbonyloxy group, a dodecylcarbonyloxy group, a nitro group, a vinyl group, etc. R ₁ and R
₂ represents an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group and an isobutyl group. Ar ₂ is an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, a decyl group, a dodecyl group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and a hexyl. Oxy group, decyloxy group, alkoxy group such as dodecyloxy group, hydroxy group, acetoxy group, propionyloxy group, butyroyloxy group, represents a phenyl group which may be substituted with an alkylcarbonyloxy group such as stearoyloxy group, A phenyl group substituted with one alkoxy group, hydroxy group or alkylcarbonyloxy group. Non-nucleophilic anionic residues of X include SbF ₆ , AsF ₆ , PF ₆ ,
(C ₆ F ₅ ) B or BF _{4 and the} like.

Representative examples of the sulfonium salt compound of the present invention are shown below. Where X in the formula is SbF ₆ , AsF ₆ ,
Indicates a non-nucleophilic anionic residue of either PF ₆ , (C ₆ F ₅ ) B or BF ₄ .

[0021]

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[0022]

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The sulfonium compound of the present invention can be produced according to the following reaction formula.

[0024]

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In the above reaction formula, Y represents a halogen atom, and M represents an alkali metal. Compounds (II) and (III),
The reaction with (IV) or (V) is carried out in an organic solvent, if necessary, at a temperature of room temperature to 100 ° C, preferably 30 to 70 ° C, for several hours to several tens of hours. After completion of the reaction, water and compound (VII) are added to the reaction solution, and the mixture is stirred. The precipitated compound is collected by filtration or extracted with an organic solvent to obtain the desired product (I).

The curable composition of the present invention contains the cationic polymerization initiator of the present invention and a cationically polymerizable compound. Examples of the cationic polymerizable compound to be used include the following compounds.

Examples of the vinyl compound include styrene compounds such as styrene, α-methylstyrene, p-methoxystyrene, and pt-butoxystyrene, methyl vinyl ether, n-butyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether, Chloroethyl vinyl ether, 2-phenoxyethyl vinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether,
Stearyl vinyl ether, alkyl vinyl ether compounds such as 2-acetoxyethyl vinyl ether, allyl vinyl ether, alkenyl vinyl ether compounds such as 2-methacryloyloxyethyl vinyl ether, 2-acryloyloxyethyl vinyl ether, phenyl vinyl ether, aryl vinyl ether compounds such as p-methoxyphenyl vinyl ether, N-vinyl carbazole, cationically polymerizable nitrogen-containing compounds such as N-vinyl pyrrolidone, butanediol divinyl ether, triethylene glycol divinyl ether, cyclohexanediol divinyl ether, 1,4-benzenedimethanol divinyl ether, hydroquinone divinyl ether,
And polyfunctional vinyl compounds such as sasolcinol divinyl ether.

As the epoxy compound, phenyl glycidyl ether, pt-butylphenyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, 1,2
-Butylene oxide, 1,3-butadiene monoxide, 1,2-dodecylene oxide, epichlorohydrin, 1,2-epoxydecane, ethylene oxide,
Monofunctional monomers such as propylene oxide, styrene oxide, cyclohexene oxide, 3-methacryloyloxymethylcyclohexene oxide, 3-acryloyloxymethylcyclohexene oxide, 3-vinylcyclohexene oxide, and 4-vinylcyclohexene oxide; Tetradecadienedoxide, limonenedoxide, 3,4-epoxycyclohexylmethyl- (3,4-epoxycyclohexyl) carboxylate, di (3,4-epoxycyclohexyl) adipate, phenylglycidyl ether, bisphenol A type epoxy resin , Bisphenol F type epoxy resin, cresol novolak type epoxy resin, phenol novolak type epoxy resin, polyglycidyl ester of polyhydric alcohol Polyfunctional epoxy compounds such as ether and the like.

As the bicyclo orthoester compound, 1
-Phenyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-hydroxymethyl-2,6,7-trioxabicyclo [2,2
2,2] -octane and the like.

As the spiro orthocarbonate compound,
1,5,7,11-tetraoxaspiro [5,5] undecane, 3,9-dibenzyl-1,5,7,11-tetraoxaspiro [5,5] undecane, 1,4,6-trioxas Pyro [4,4] nonane, 2-methyl-1,
4,6-trioxaspiro [4,4] nonane, 1,4
6-trioxaspiro [4,5] decane and the like.

As oxetane compounds, 3,3-dimethyloxetane, 3,3-bis (chloromethyl) oxetane, 2-hydroxymethyloxetane, 3-methyl-3
-Oxetane methanol, 3-methyl-3-methoxymethyloxetane, 3-ethyl-3-phenoxymethyloxetane, resorcinol bis (3-methyl-3-oxetanylethyl) ether, m-xylylenebis (3-
Ethyl-3-oxetanyl ethyl ether) and the like.

Of these, glycidyl ether epoxy and alicyclic epoxy are particularly preferred. One or more of the above polymerizable compounds can be used.

A curable composition can be obtained by mixing a cationic polymerization initiator containing a sulfonium salt compound with these cationically polymerizable compounds. In the curable composition of the present invention, the cationic polymerization initiator, the sulfonium salt compound in the cationic polymerization initiator, 100 parts by weight of the cationically polymerizable compound, 0.01 parts by weight to 20 parts by weight,
Preferably, it is used in an amount of 0.1 to 10 parts by weight. When the amount is less than 0.01 part by weight, the curing of the curable composition does not proceed very much. When more than 20 parts by weight,
One-part storage stability is poor, and the mechanical strength and heat resistance of the cured product are reduced.

The curable composition can be used in a state where the cationically polymerizable compound and the cationic polymerization initiator are simply mixed, or in a varnish state where necessary, a solvent is added.
Although the curable composition of the present invention can be used for various applications, for example, it can be suitably used as a paint or an adhesive resin, in which case the curable composition is applied to a metal plate or the like, and dried if necessary. Through the process, cured at the required temperature, several μm
A cured product having a thickness of several tens of μm can be obtained from a thin film having a thickness of about several tens of μm.

As described above, according to the sulfonium compound and the cationic polymerization initiator according to the first and second aspects, the cationically polymerizable compound can be cured at a temperature of 100 ° C. or less. The curable composition according to claims 3 and 4 is a one-liquid state containing a cationically polymerizable compound and a cationic polymerization initiator, and the cationic polymerization initiator contains the sulfonium salt compound of the present invention. From
It can be stored stably for a long time.

[0036]

Next, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

1. Synthesis of Sulfonium Salt Compound (Example 1) Synthesis of 3- (4-methoxyphenyl) -2-propylphenylmethylsulfonium hexafluorophosphonate 25.84 g of 3- (4-methoxyphenyl) -2-propylphenyl sulfide and dimethyl sulfate 13.24 g were mixed and reacted at 50 ° C. for 10 hours. 300 ml of distilled water and 100 ml of ethyl acetate were added to the reaction product, and after stirring and standing, the aqueous layer was taken out, and potassium hexafluorophosphate 1 was added.
8.41 g and 300 ml of ethyl acetate were added and stirred. The ethyl acetate layer was washed twice with 100 ml of distilled water, and after removing the water content of the ethyl acetate layer with anhydrous magnesium sulfate, the ethyl acetate was distilled off by an evaporator. The obtained crude product was further dried at 40 ° C. under reduced pressure. The yield was 28.8 g. IR spectrum data of the obtained compound was measured, and it was confirmed that the compound was 3- (4-methoxyphenyl) -2-propylphenylmethylsulfonium hexafluorophosphonate. Table 1 shows the spectrum data.

(Examples 2 to 7) The sulfonium salt compound of the present invention produced in the same manner as in Example 1 and its spectrum data are shown in Table 1 together with Example 1.

[0039]

[Table 1]

2. Preparation of curable composition 3 g of the sulfonium salt compound obtained in Examples 1, 3 and 5 was added to 100 g of UVR-6410 (bisphenol A type epoxy manufactured by UCC) which is a polymerizable compound.
2 g of each of the sulfonium salt compounds obtained in Example 7 were mixed to obtain four types of curable compositions. In addition, curable compositions were similarly prepared using 3 g of the sulfonium salt compounds of Comparative Examples 1 to 4 shown in Table 2. The compounds of Comparative Examples 1 and 2 were conventionally known as thermosetting catalysts. The compounds of Comparative Examples 3 and 4 are described in International Publication WO95 / 2.
No. 4387.

3. Evaluation of Curable Composition (1) Thermosetting Test 10 g of the curable composition obtained in 2 was weighed in a sample bottle and left in an oven controlled at 90 ° C. for 30 minutes to be taken out. Table 2 summarizes the results. In Table 2, those that were cured were indicated by 、, and those that were not cured were indicated by x. (2) One-pack storage stability test 100 g of the curable composition obtained in 2 was weighed in a sample bottle, left in a thermostat at 25 ° C, and taken out after 2 weeks.
If the viscosity after standing is less than twice that of before standing,
Those exceeding 2 times are shown in Table 2 as x.

[0042]

[Table 2]

Table 2 shows that the sulfonium salt compound of the present invention can cure a polymerizable compound at 90 ° C. and has excellent one-pack storage stability.

[0044]

By using the sulfonium salt compound of the present invention and the cationic polymerization initiator containing the same, the cationically polymerizable compound can be cured at a temperature of 100 ° C. or lower. Further, the curable composition of the present invention can be stably stored for a long period of time because it contains the cationically polymerizable compound and the cationic polymerization initiator of the present invention.

Claims (4)

[Claims] 1. A compound of the general formula (I) (Wherein, Ar ₁ is an optionally substituted phenyl group or a naphthyl group, but R ₁ and R ₂ represents a .Ar ₂ is optionally substituted phenyl group represents an alkyl group having 1 to 4 carbon atoms A phenyl group substituted with at least one of an alkoxy group, a hydroxy group and an alkylcarbonyloxy group, and X represents a non-nucleophilic anion residue.) 2. A cationic polymerization initiator comprising the sulfonium salt compound according to claim 1. 3. A curable composition comprising a cationically polymerizable compound and the cationic polymerization initiator according to claim 2. 4. The curable composition according to claim 3, wherein the cationically polymerizable compound is a glycidyl ether type epoxy or an alicyclic epoxy.