JPH0751630B2 - Curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Field of Application> The present invention relates to a curable composition, more specifically 4,4′-
Bis (methacryloylthio) diphenyl sulfide, 4,
The present invention relates to a curable composition containing, as an essential component, another vinyl-based monomer copolymerizable with 4'-bis (methacryloylthio) diphenyl sulfide and polythiols. The curable composition of the present invention is not only excellent in curability, but the cured product obtained by curing the curable composition has a high refractive index and also excellent low water absorption and optical uniformity. Therefore, optical materials, coating agents, sealants, paints,
It is extremely useful in industrial fields such as adhesives, especially in the field of optical materials.

<Prior Art> Polystyrene resins, polymethylmethacrylate resins, polycarbonate resins, polymers of diethylene glycol diallyl carbonate, etc. have been conventionally used as organic optical materials, and these are lightweight, safe and processable. In addition, the demand is increasing in recent years due to its excellent dyeability.

However, the conventional organic optical material, for example, in the case of a polymethylmethacrylate resin, has a large hygroscopic property as its resin property, and therefore its shape and refractive index change, and it is unstable as an optical material. Further, polystyrene resins and polycarbonate resins have drawbacks such as optical birefringence, generation of scattered light, and deterioration of transparency due to aging. Further, the polymer of diethylene glycol diallyl carbonate has a low refractive index (refractive index = 1.499), so that its application range as an optical material is naturally limited.

Various resins for optical materials have been proposed to improve these drawbacks. Examples of these include, for example, JP-A-57
-28115, 57-28116, 59-184210, 60-7314, 60-179406, 60-21
No. 7301, No. 60-186514, No. 60-166307, No. 60-103301, No. 60-124607, No. 62-
No. 232414, No. 62-235901, No. 62-267316, No. 63-15811, No. 63-46213, No. 63-72
No. 707, No. 63-75022, No. 63-113012,
63-130614, 63-130615, and 63-1704.
No. 01, No. 63-170404, No. 63-191813,
63-248811, 63-251408, 63-2687.
No. 07, No. 64-54021 and the like can be mentioned. However, the cured product obtained by these prior art is optically non-uniform, weathering coloring is remarkable,
It was not always a satisfactory material as an optical material such as lack of dimensional stability.

<Problems to be Solved by the Invention> An object of the present invention is to overcome the drawbacks of the above-mentioned conventional resins for optical materials and not only be suitable as optical materials, but also coating agents, sealants, paints, adhesives, etc. Another object of the present invention is to provide a curable composition suitable for producing a well-balanced cured product having various physical properties such as optical uniformity and low water absorption, which can also be used as the material.

<Means for Solving the Problems> The inventors of the present invention, as a result of earnest research in light of the present situation,
The inventors have found the means for solving the problems and arrived at the present invention.

That is, the present invention provides (A) Formula (I) 4,4'-bis (methacryloylthio) diphenyl sulfide represented by (B) Another vinyl type copolymerizable with 4,4'-bis (methacryloylthio) diphenyl sulfide represented by the above formula (I) A monomer and (C) a polythiol represented by the formula (II) R- (SH) _n (II) (wherein R is a polyvalent organic group, and n is an integer of 2 or more) The content of the component (B) in the total amount of the component (A), the component (B) and the component (C) is 10 to 90% by weight, and the content of the component (C) based on the methacryloyl group of the component (A) is The present invention relates to a curable composition having a functional group equivalent ratio of mercapto groups in the range of 0.001 to 1.01.

The 4,4'-bis (methacryloylthio) diphenyl sulfide represented by the above formula (I) used as the component (A) in the present invention has the following formula (III) It can be obtained by dissolving 4,4'-dimercaptodiphenyl sulfide represented by the following in, for example, an alkaline aqueous solution, and reacting this with methacrylic acid chloride.

The component (A) represented by the formula (I), 4,4′-bis (methacryloylthio) diphenyl sulfide, can be easily mixed with other organic compounds and has extremely low affinity with water, and The cured product has a high refractive index (refractive index = 1.
689). Therefore, this (A)
Improvement of the refractive index of a cured product obtained by curing the composition by mixing the components with other vinyl-based monomers and polythiols that are copolymerizable with the component (A) at a compounding ratio according to the purpose of use, It is possible to reduce the water absorption rate.

Further, the other vinyl-based monomer copolymerizable with the component (A) used as the component (B) in the present invention is
There is no particular limitation as long as it is compatible with the component (A). Examples of other vinyl monomers copolymerizable with the component (A) include unsaturated fatty acid esters, aromatic vinyl compounds, unsaturated fatty acids and their derivatives, unsaturated dibasic acids and their derivatives, (meth) acrylonitrile. Vinyl cyanide compounds and the like. The unsaturated fatty acid ester includes methyl (meth) acrylate (in the present specification, refers to both methyl acrylate and methyl methacrylate, and the same in other cases), ethyl (meth) acrylate, butyl (meth) acrylate, 2- Ethylhexyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate,
Alkyl (meth) acrylates such as (iso) bornyl (meth) acrylate and adamantyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth)
Acrylate, 1-naphthyl (meth) acrylate, fluorophenyl (meth) acrylate, chlorophenyl (meth) acrylate, bromophenyl (meth) acrylate, tribromophenyl (meth) acrylate, methoxyphenyl (meth) acrylate, cyanophenyl (meth) Acrylic acid aromatic esters such as acrylate, biphenyl (meth) acrylate, bromobenzyl (meth) acrylate, fluoromethyl (meth) acrylate, chloromethyl (meth) acrylate, bromoethyl (meth) acrylate, trichloromethyl (meth) acrylate, etc. Haloalkyl (meth) acrylate, 2-
In addition to hydroxyethyl (meth) acrylate, polyethylene glycol ester of (meth) acrylic acid, and the like, (meth) acrylic acid ester such as glycidyl (meth) acrylate and alkylamino (meth) acrylate can be given. Further, α-substituted acrylic acid esters such as α-fluoroacrylic acid ester and α-cyanoacrylic acid ester may be used.

As the aromatic vinyl compound, styrene, or α-substituted styrene such as α-methylstyrene, α-ethylstyrene, and α-chlorostyrene, nuclear substitution such as fluorostyrene, chlorostyrene, bromostyrene, chloromethylstyrene, and methoxystyrene. Styrene is an example.

Unsaturated fatty acids and their derivatives include (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N
-(Meth) acrylamides such as diethyl (meth) acrylamide, (meth) acrylic acid and the like.

Examples of the unsaturated dibasic acid and its derivative include N-methylmaleimide, N-ethylmaleimide, N-butylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-methylphenylmaleimide, N-chlorophenylmaleimide and N-carboxy. Examples thereof include N-substituted maleimides such as phenylmaleimide, maleic acid, maleic anhydride and fumaric acid.

In addition to the above monofunctional vinyl monomers, other vinyl monomers copolymerizable with the component (A) used in the present invention include crosslinkable polyfunctional monomers. For example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,3-butylene glycol Di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,5-pentadiol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate , Hydroxypivalic acid neopentyl glycol ester di (meth) acrylate, oligoester di (meth) acrylate, polybutadiene di (meth) acrylate, 2,2-bis (4- (meth) acryloyloxyphenyl) propane, 2 , 2-bis (4- (ω- (meth) acryloyloxypolyethoxy) phenyl) propane,
2,2-bis (4- (ω- (meth) acryloyloxypolyethoxy) dibromophenyl) propane, 2,2-bis (4- (ω- (meth) acryloyloxypolypropoxy) phenyl) propane, bis (4 Di (meth) acrylates such as-(ω- (meth) acryloyloxypolyethoxy) phenyl) methane, diallyl phthalate, diallyl isophthalate, diallyl terephthalate, diallyl carbonate, diethylene glycol diallyl carbonate, divinylbenzene, divinylbiphenyl, N ,
Bifunctional crosslinkable monomers such as N'-m-phenylene bismaleimide, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tri (meth) allyl isocyanate Examples thereof include trifunctional crosslinking monomers such as nurate, triallyl trimellitate and diallyl chlorendate, and tetrafunctional crosslinking monomers such as pentaerythritol tetra (meth) acrylate. Two or more kinds of the other vinyl-based monomers copolymerizable with the component (A) may be mixed and used.

Further, as the polythiols represented by the above formula (II) used as the component (C) in the present invention, aliphatic polythiols or aromatic polythiols in which n is 2 or more, and preferably n is an integer of 2 to 5 Is preferred, especially n
Is preferably an aliphatic polythiol having an integer of 2 to 5. Typical examples of polythiols include, for example, 9,10-
Anthracene dimethanethiol, 1,11-undecanedithiol, 4-ethylbenzene-1,3-dithiol, 1,2-
Ethanedithiol, 1,8-octanedithiol, 1,18-
Octadecanedithiol, 2,5-dichlorobenzene-1,3
-Dithiol, 1,3- (4-chlorophenyl) propane-2,2-dithiol, 1,1-cyclohexanedithiol,
1,2-cyclohexanedithiol, 1,4-cyclohexanedithiol, 1,1-cycloheptanedithiol, 1,1-cyclopentanedithiol, 4,8-dithiaundecane-1,1
1-dithiol, dithiopentaerythritol, dithiothreitol, 1,3-diphenylpropane-2,2-dithiol, 1,3-dihydroxy-2-propyl-2 ', 3'-
Dimercaptopropyl ether, 2,3-dihydroxypropyl-2 ′, 3′-dimercaptopropyl ether, 2,
6-dimethyloctane-2,6-dithiol, 2,6-dimethyloctane-3,7-dithiol, 2,4-dimethylbenzene-1,3-dithiol, 4,5-dimethylbenzene-1,3-dithiol, 3,3-dimethylbutane-2,2-dithiol, 2,
2-dimethylpropane-1,3-dithiol, 1,3-di (4
-Methoxyphenyl) propane-2,2-dithiol, 3,4
-Dimethoxybutane-1,2-dithiol, 10,11-dimercaptoundecanoic acid, 6,8-dimercaptooctanoic acid,
2,5-dimethylcapto-1,3,4-thiadiazole, 2,2 '
-Dimercaptobiphenyl, 4,4'-dimethylcaptobiphenyl, 4,4'-dimercaptobibenzyl, 3,4-dimercaptobutanol, 3,4-dimercaptobutylacetate, 2,3-dimercapto-1-propanol 1,2-dimercapto-1,3-butanediol, 2,3-dimercaptopropionic acid, 1,2-dimercaptopropyl methyl ether, 2,3-dimercaptopropyl-2 ′, 3′-dimethoxypropyl ether , 3,4-thiophenedithiol,
1,10-decanedithiol, 1,12-dodecanedithiol,
3,5,5-Trimethylhexane-1,1-dithiol, 2,5-
Toluenedithiol, 3,4-Toluenedithiol, 1,4-
Naphthalenedithiol, 1,5-naphthalenedithiol,
2,6-naphthalenedithiol, 1,9-nonanedithiol,
Norbornene-2,3-dithiol, bis (2-mercaptoisopropyl) ether, bis (11-mercaptoundecyl) sulfide, bis (2-mercaptoethyl) ether, bis (2-mercaptoethyl) sulfide, bis (18-mercapto) Octadecyl) sulfide, bis (8-mercaptooctyl) sulfide, bis (12-mercaptodecyl) sulfide, bis (9-mercaptononyl) sulfide, bis (4-mercaptobutyl) sulfide, bis (3-mercaptopropyl) ether, bis (3-mercaptopropyl) sulfide, bis (6-
Mercaptohexyl) sulfide, bis (7-mercaptoheptyl) sulfide, bis (5-mercaptopentyl) sulfide, 2,2'-bis (mercaptomethyl) acetic acid, 1,1-bis (mercaptomethyl) cyclohexane,
Bis (mercaptomethyl) durene, phenylmethane-
1,1-dithiol, 1,2-butanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 2,2-butanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 2, 2-propanedithiol, 1,2-hexanedithiol, 1,6-hexanedithiol, 2,5-hexanedithiol, 1,7-heptanedithiol, 2,6-heptanedithiol, 1,5-pentanedithiol, 2,4 -Pentanedithiol, 3,3-pentanedithiol, 7,8-heptadecanedithiol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 2-methylcyclohexane-1,1-dithiol 1,2-methylbutane-2,3-dithiol, ethylene glycol dithioglycolate, ethylene glycol bis (3-mercaptopropionate) Pantrithiol, 1,2,4-butanetrithiol, trimethylolpropane trithioglycolate, trimethylolpropane tris (3-mercaptopropionate), pentaerythritol trithioglycolate, pentaerythritol tris (3-mercaptopropionate) ),
Trithiols such as 1,3,5-benzenetrithiol and 2,4,6-mesitylenetrithiol, and neopentanetetrathiol, 2,2'-bis (mercaptomethyl) -1,3-propanedithiol, pentaerythritol Tetrakis (3-mercaptopropionate), 1,3,5-benzenetrithiol, 2,4,6-toluenthithiol, 2,4,6-
Examples include mesitylene trithiol. The polythiols as the component (B) exemplified above can be used alone or as a mixture of two or more kinds. By mixing the polythiols with the components (A) and (B) at a compounding ratio according to the purpose of use, it is possible to improve the impact resistance of a cured product obtained by curing the composition.

When blending 4,4′-bis (methacryloylthio) diphenyl sulfide as the component (A), another vinyl-based monomer copolymerizable with the component (A) as the component (B) and polythiols as the component (C), The content of the (B) component in the total amount of the (A) component, the (B) component and the (C) component is 10 to 90% by weight, preferably 15 to 85% by weight, and the methacryloyl group of the (A) component. The functional group equivalent ratio of the mercapto group of the component (C) with respect to the range of 0.001 to 1.01, preferably 0.01 to
It is blended to be in the range of 1.0.

When the amount of component (B) used is less than 10% by weight,
The resulting cured product becomes brittle, resulting in insufficient mechanical properties, which is not preferable. Further, when the amount of the component (B) used is more than 90% by weight, there is a problem in any of the optical characteristics, water absorption and heat resistance, which is not preferable.

Further, if the functional group equivalent ratio of the mercapto group of the component (C) to the methacryloyl group of the component (A) is less than 0.001, the cured product becomes brittle, which is not practical. Further, when the functional group equivalent ratio is more than 1.01, when the curable composition is cured, not only polymerization spots due to unreacted mercapto groups occur, but also the hardness of the cured product due to insufficient crosslinking. Is significantly reduced, which is not preferable.

The curable composition of the present invention can be cured by radical polymerization. The radical polymerization initiator used in the radical polymerization, heat, microwaves, infrared rays, it is possible to use any radical polymerization initiator as long as it can generate a radical by ultraviolet rays, the application of the curable composition, It can be appropriately selected according to the purpose.

Radical polymerization initiators that can be used in the polymerization by heat, microwaves, infrared rays include, for example, 2,2′-azobisisobutyronitrile, 2,2′-azobisisovaleronitrile, 2,2′-azobis (2 , 4-dimethylvaleronitrile) and other azo compounds, methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, cyclohexanone peroxide, acetylacetone peroxide and other ketone peroxides, isobutyryl peroxide,
2,4-dichlorobenzoyl peroxide, o-methylbenzoyl peroxide, lauroyl peroxide, p-
Diacyl peroxides such as chlorobenzoyl peroxide, hydroperoxides such as 2,4,4-trimethylpentyl-2-hydroperoxide, diisopropylbenzene peroxide, cumene hydroperoxide and t-butyl peroxide, dicumyl Dialkyl peroxides such as peroxide, t-butylcumyl peroxide, di-t-butyl peroxide, tris (t-butylperoxy) triazine, 1,1-di-t-butylperoxycyclohexane, 2,2 -Peroxyketals such as di (t-butylperoxy) butane, t-butylperoxypivalate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, di-t
-Butylperoxyhexahydroterephthalate, di-
t-butylperoxyazelate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxyacetate, t-butylperoxybenzoate, di-t-butylperoxytrimethyladipate, etc. Examples thereof include alkyl peresters, diisopropyl peroxydicarbonate, di-sec-butyl peroxy dicarbonate, t-butyl peroxy isopropyl carbonate and the like.

Radical polymerization initiators that can be used in the polymerization by ultraviolet rays include, for example, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 4'-isopropyl-2-hydroxy-2.
-Methylpropiophenone, 2-hydroxy-2-methylpropiophenone, 4,4'-bis (diethylamino)
Benzophenone, benzophenone, methyl (o-benzoyl) benzoate, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, 1-
Phenyl-1,2-propanedione-2- (o-benzoyl) oxime, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin octyl ether, benzyl, benzyl dimethyl ketal, benzyl diethyl ketal, Examples thereof include carbonyl compounds such as diacetyl, anthraquinone or thioxanthone derivatives such as methylanthraquinone, chloroanthraquinone, chlorothioxanthone, 2-methylthioxanthone and 2-isopropylthioxanthone, and sulfur compounds such as diphenyl disulfide and dithiocarbamate.

The amount of the radical polymerization initiator used cannot be determined unconditionally because it varies depending on the type of radical polymerization initiator, the type of charged monomers and the composition ratio, but it is usually the component (A), the component (B).
It is in the range of 0.001 to 20 mol% and preferably in the range of 0.01 to 10 mol% based on the total amount of the components and the component (C). When the amount of the radical polymerization initiator used is less than 0.001 mol%, the polymerization does not proceed substantially, and when the amount used exceeds 20 mol%, it is not economical and foaming may occur during the polymerization, or it may be obtained by the polymerization. The resulting cured product has a significantly reduced molecular weight, which is not preferable.

The curable composition of the present invention can also be used by blending various fillers as needed when light-transmitting property is not particularly required. As the filler used here, other than glass fiber, alumina fiber, carbon fiber, aramid fiber, etc., silica, alumina, barium sulfate,
A powdery filler such as titanium oxide can be used. In addition, it goes without saying that flame retardants, dyes, pigments and the like can be used in combination.

The polymerization temperature and the polymerization time at the time of curing the curable composition cannot be unconditionally specified because they vary depending on the type and the amount of the radical polymerization initiator used, but the polymerization temperature is usually in the range of 0 to 200 ° C. The polymerization time is preferably 0.5 to 50 hours.

<Examples> Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

The physical properties of the cured products obtained in the examples and comparative examples were measured by the following methods.

(1) Refractive Index The refractive index at 20 ° C. was measured using an Abbe refractometer (3L type, manufactured by Shimadzu Corporation).

(2) Light transmittance Using a spectrophotometer (Hitachi, 150-20 type),
The transmittance of a flat plate having a thickness of 3 mm was measured with light of 550 nm.

(3) Glass transition temperature (Tg) Viscoelasticity measuring device (Orientec, Rheovibron)
The glass transition temperature (Tg) of the sample (thickness 0.1 mm) was determined by reading the tan δ peak using DDV-II-EP type).
And

(4) Water absorption rate The rate of weight increase when a sample dried under reduced pressure at 50 ° C for 5 days was immersed in 100 ° C water for 2 hours using a JIS-K-7209 test piece, based on the dry weight. It was

Example 1 30 g (77.6 mmol) of 4,4'-bis (methacryloyl) diphenyl sulfide as the component (A), 15 g (150 mmol) of methyl methacrylate as the component (B) and the symbol K shown in Table 2 50 g of a mixture consisting of 5 g (10.2 mmol) of polythiols as a radical polymerization initiator
2,2'-Azobis (2,4-dimethylvaleronitrile) 0.2g
Was dissolved to obtain a curable composition. This curable composition
5 cm x 5 cm x 0.3 cm glass mold and 0.2 mm x 50 mm x 20
Inject each into a glass cell of mm, and under a nitrogen stream at 35 ° C.
After heating for 10 hours at 80 ° C., the temperature was raised to 80 ° C. at a temperature rising rate of 10 ° C./hr, and the mold was removed.

The obtained cured product was a uniform, colorless and transparent resin. The physical properties of the cured product are shown in Table 3.

Examples 2 to 10 and Comparative Examples 1 to 5, 4,4′-bis (methacryloyl) diphenyl sulfide as the component (A), the vinyl-based monomer as the component (B) shown in Table 1 and Table 2 ( A cured product was obtained in the same manner as in Example 1, except that the polythiols as the component C) were mixed in the proportions shown in Table 3, respectively. However, in Comparative Example 3, 2 g of isopropyl peroxydicarbonate was used instead of 2,2'-azobis (2,4-dimethylvaleronitrile). The physical properties of each of the obtained cured products are shown in Table 3.

As is clear from Table 3, as compared with the cured products obtained in Comparative Examples 1 to 5, the cured products obtained by curing the curable composition of the present invention have a high refractive index and a small water absorption. I understand.

<Effects of the Invention> The curable composition of the present invention not only has excellent curability, but the cured product obtained by curing the curable composition of the present invention has excellent optical uniformity. Its high refractive index, physical properties such as high heat resistance and low water absorption make it particularly useful in the industrial field of optical materials, as well as coating agents, sealants, paints, and adhesives. It is also useful in industrial fields such as.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Haruo Yoshida Oita City, Oita Prefecture 2 in Nakazai, Showa Denko Co., Ltd. Oita Research Co., Ltd. (72) Inventor Hirotaka Tagoshi 2 Oita City, Oita Prefecture 2 Showa Denko (56) Reference JP-A-3-54226 (JP, A) JP-A-2-160762 (JP, A) JP-A-2-113027 (JP, A) JP-A-2-298506 ( JP, A) Japanese Patent 6-70003 (JP, B2) Japanese Patent 6-81770 (JP, B2)

Claims (1)

[Claims] 1. (A) Formula (I) 4,4'-bis (methacryloylthio) diphenyl sulfide represented by (B) Another vinyl type copolymerizable with 4,4'-bis (methacryloylthio) diphenyl sulfide represented by the above formula (I) A monomer and (C) a polythiol represented by the formula (II) R- (SH) _n (II) (wherein R is a polyvalent organic group, and n is an integer of 2 or more) The content of the component (B) in the total amount of the component (A), the component (B) and the component (C) is 10 to 90% by weight, and the content of the component (C) based on the methacryloyl group of the component (A) is A curable composition having a functional group equivalent ratio of mercapto groups in the range of 0.001 to 1.01.