JPS6320256B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel curable resin composition. Specifically, it consists of an addition product of an epoxy group-containing organic compound (at least one molecule of the compound must be allyl glycidyl ether) to substituted or unsubstituted allyl alcohol, and at least two epoxy group-containing molecules are present in each molecule. An unsaturated component containing a carbon-carbon double bond (hereinafter referred to as polyene) and at least two thiol groups (SH group) in one molecule.
The present invention relates to a novel curable resin composition comprising a component containing polythiol (hereinafter referred to as polythiol) and having excellent curability. In general, thiol groups undergo an addition reaction with carbon-carbon unsaturated bonds, and the reaction is promoted in an ionic manner by an acid or base catalyst, and in a radical manner by a radical generator or irradiation with active energy rays such as ultraviolet rays. It is known that Based on these principles, various curable resin compositions composed of polythiol compounds and polyene compounds have been proposed. When applying these curable resin compositions to coatings, cast products, etc., the properties of the resin composition are suitable for handling operations, the curing speed is sufficient, and the physical properties of the cured product are good. It must exhibit various physical properties depending on the intended use, and it is generally not easy to satisfy these demands in a well-balanced manner. Conventionally, unsaturated compounds with simple carbon-carbon double bonds, such as prebutadiene and polyisoprene,
Since the curing reaction with polythiol is not fully satisfactory, allyl ester, allyl urethane, acrylic ester, vinyl ether, vinyl thioether, N-vinyl compound, unsaturated polyester or vinyl are used as polyenes with double bonds that are highly reactive with polythiol. Compounds with cycloacetal bonds have been proposed. However, these polyenes are also subject to various problems. Acrylic esters are irritating to the skin and mucous membranes and have an adverse effect on painting workers, unsaturated polyesters do not have sufficient curing properties, and vinyl cycloacetal compounds have poor hydrolysis resistance. Although vinyl compounds have a high curing speed, they are difficult to obtain industrially and have low practical value. Among these, allyl compounds can be said to be relatively superior polyenes in terms of curability, ease of industrial production, and physical properties of cured products, but are still unsatisfactory in terms of curing speed and mechanical strength of cured products. It's hard to say that we're getting what we could. In recent years, various curing systems have been proposed in response to social demands for resource saving, energy saving, and non-pollution, and this curing system made of polyene-polythiol also contributes to these demands, and we hope to develop technologies that better meet the needs of society. The development of this was eagerly awaited. Particularly when this curing system is carried out by irradiation with active energy, it is desired that the cured product has sufficient curing speed and sufficient mechanical strength. Taking these points into consideration, the present inventors have developed a polyene that does not cause skin irritation, has sufficient hydrolysis resistance, has a curing speed, and has better mechanical strength of the cured product than conventional allyl polyenes. The development goal was to obtain a polyene that can be easily obtained industrially, and as a result of intensive study, we found that a polyene obtained by adding an epoxy group-containing compound to substituted or unsubstituted allyl alcohol was found to be a substitute for conventional allyl type polyenes. The present inventors have discovered that the curing speed is significantly improved compared to the conventional method. In order to clarify the features of this new polyene, the following points are listed in detail. First of all, since the polyene of the present invention is an allyl ether type, it has high reactivity. The difference in reactivity between olefins and thiol groups has been studied [J, Polym. Sci., 15 , 627-645.
(1977)], according to which allyl ether (CH ₂ =
CH―CH ₂ -O―) type olefin is N-allylic urethane (CH ₂ = CH―CH ₂ -NHCO ₂ -) type olefin and O-allylic urethane (CH ₂ = CH―) type olefin.
It is known that the reaction rate is 16 times that of CH ₂ -O ₂ CNH-) type olefin. The curable resin composition provided by the present invention reflects the high reactivity of allyl ether type olefin, and has a higher curing speed than conventionally provided curable compositions using allyl type polyene. It has the great feature of producing a coating film with excellent mechanical strength. Second, as mentioned above, a very useful allyl ether type polyene can be easily obtained. Conventionally, allyl ether type polyenes have been extremely difficult to manufacture. For example, when making trimethylolpropane triallyl ether, allyl halide and trimethylolpropane are added.
Make trimethylolpropane triallyl ether using NaOH. At this time, the production of diallyl ether as a by-product was unavoidable, the yield was low, and the process was technically complicated as it was necessary to remove the salt produced as a by-product. In contrast, in the present invention, there are no by-products and allyl ether type polyene can be easily obtained quantitatively. Thirdly, the molecular design of polyenes is easy and diverse, and the required physical properties of the cured product can be easily met. For example, by using epichlorohydrin as the epoxy group-containing compound, chlorine atoms can be introduced into the polyene, thereby imparting adhesive properties and flame retardancy. Furthermore, by using a plurality of allyl glycidyl ethers, the number of functional groups in the carbon-carbon double bond can be arbitrarily selected, and the required physical properties can be easily met. In addition, the polyene of the present invention is free from irritation and odor unlike acrylic polyenes. In addition to the above, another feature of the present invention is that when subjected to a curing reaction by actinic radiation, polymerization inhibition by oxygen, which was observed in conventional acrylic photocurable compositions, is not observed. The curable resin composition of the present invention contains one or more polythiol compounds () as an essential component.
and the general formula (In the formula, R is a group selected from a hydrogen atom, a phenyl group, and an alkyl group having 1 to 10 carbon atoms, and may be the same or different. Y is ethylene oxide, propylene oxide, butylene oxide, styrene The ring-opened group formed by cleavage of the carbon-oxygen bond of the epoxy group of one or more epoxy compounds selected from the group consisting of oxide, cyclohexene oxide, epihalohydrin, and allyl glycidyl ether is formed singly, in a block shape, or randomly. Groups arranged in the form of Y
(Contains a ring-opened group formed by cleavage of the carbon-oxygen bond of at least one epoxy group of allyl glycidyl ether) having at least two carbon-carbon double bonds in the molecule; It is characterized by containing two or more types of polyene compounds (). Polythiol (), which is an essential component of the present invention, has the general formula A-(SH) _q [where A is a q-valent organic residue that does not have an unsaturated bond reactive with the SH group, q is an integer of 2 or more], the molecular weight is 80 to 10,000, and the viscosity at 50°C is almost 0 to 10,000 poise.
Preferred examples of such polythiols include thioglycolic acid, α-mercaptopropionic acid,
Polythiols derived by the esterification reaction of β-mercaptopropionic acid and polyhydric alcohol, and aliphatic and aromatic polythiols such as ethanediol, propanedithiol, hexamethylenedithiol, xylylenedithiol,
Further examples include polythiols derived by substituting mercaptan groups for the halogen atoms of epihalohydrin adducts of alcohols and hydrogen sulfide reactants of polyepoxy compounds. The polyhydric alcohols to be subjected to the esterification reaction with the above-mentioned thioglycolic acid and mercaptopropionic acid include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol,
1,6-hexanediol, neopentyl glycol, bisphenol A, hydrogenated bisphenol A, bisphenol A-ethylene oxide adduct, bisphenol A-propylene oxide adduct, thiodiethanol, trimethylolpropane, trimethylolethane, glycerin , triethanolamine, pentaerythritol, dipentaerythritol, sorbitol, hydroquinone, pyrogallol, xylylene glycol, 4,
Examples include alcohols such as 4'-dihydroxydiphenylmethane, trishydroxyethyl isocyanurate, and bishydroxyethylhydantoin. The polythiol () of the present invention can be used alone or as a mixture of two or more. The polyene () of the present invention is obtained by adding an epoxy group-containing organic compound (at least one molecule in the compound must be allyl glycidyl ether) to substituted or unsubstituted allyl alcohol. The adduct of an epoxy group-containing organic compound to substituted or unsubstituted allyl alcohol can be obtained by _various known methods.
It can be easily obtained by charging allylglycidyl ether, dropping allyl glycidyl ether at elevated temperature (approximately 60°C), and completing the reaction. Examples of substituted or unsubstituted allyl alcohols that can be used here include allyl alcohol,
Crotyl alcohol, 1-hydroxy-pentene-2, 1-hydroxy-hexene-2, 1-hydroxy-heptene-2, 1-hydroxy-nonene-2, 1-hydroxy-decene-2, 3-hydroxy-butene- 1,3 hydroxy-pentene-
2,2-hydroxy-hexene-3,3-hydroxy-2',3-dimethyl-butene-1,4-hydroxy-2,3,4-trimethylpentene-2,
Examples include 2-hydroxy-2,3,4,5-tetramethylhexene-3. Examples of organic compounds containing epoxy groups include ethylene oxide, propylene oxide, butylene oxide, allyl glycidyl ether, cyclohexene oxide, styrene oxide, and epihalohydrin, which may be added alone or as a mixture of two or more in a random or block form. At least it can be used. However, in any case at least one molecule of allyl glycidyl ether must be included in the addition product. Examples of the polyene () include allyl glycidyl ether adduct of allyl alcohol, allyl glycidyl ether of allyl alcohol and shrimp chlorohydrin adduct, allyl glycidyl ether of allyl alcohol and ethylene oxide adduct, allyl glycidyl ether of allyl alcohol and epichlorohydrin. and ethylene oxide adducts. The polyene () of the present invention can be used alone or as a mixture of two or more. The viscosity of the polyene of the present invention is almost 0 at 50°C.
to 10000 poise, preferably almost 0 to 10000
It's poise. Polythiol () used in the present invention
The blending ratio of and polyene () is such that the equivalent ratio of carbon-carbon double bond to thiol group is 0.70/1 to 1.
Preferably, the ratio is selected to be 1.5/1,
In particular, a value around 1 gives preferable results. The curable resin composition of the present invention can be used as a curable composition by actinic radiation, a curable composition by a radical generator, and even as a curable composition that can be cured by heating after being cured by actinic rays. I can do it. Examples of active radiation include visible light, ultraviolet rays, electron beams, and X-rays. When used as an ultraviolet curable composition, a photosensitizer is added to the mixture of the polythiol compound () and polyene compound () to induce an ultraviolet curing reaction. The amount of the photosensitizer to be added can be appropriately selected depending on its type, and is preferably added in an amount of 0.1 to 10 parts by weight per 100 parts by weight of the mixture of polythiol () and polyene (). Examples of the photosensitizer include aromatic carbonyl compounds, benzoin ether compounds, azide compounds, azo compounds, diazo compounds, and peroxide compounds. Here, aromatic carbonyl compounds include benzophenone, acetophenone, benzaldehyde, p,p'-dimethylaminobenzophenone, etc., and benzoin ether compounds include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether,
Benzoin butyl ether, benzoin isoallyl ether, benzoin octyl ether, etc.
Examples of azide compounds include 4,4'-diazidostilbene and p-phenylenebisazide. Examples of azo compounds include 2,2'-azobisbutyronitrile, 2,2'-azobisdimethylvaleronitrile, etc.
Examples of the diazo compound include diazoaminobenzene, and examples of the peroxide compound include di-tert-butyl peroxide, and these may be used alone or as a mixture of two or more. When the curable resin composition of the present invention is used as a radical curable composition, the purpose can be achieved by adding a radical generator in place of the above-mentioned photosensitizer. By appropriately selecting a radical generator, it is possible to achieve both room temperature curability and heat curability. Examples of the radical generator include peroxides, azo compounds, and combinations of peroxides and decomposition accelerators. Peroxides include ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide, diacyl peroxides such as benzoyl peroxide and lauroyl peroxide, hydroperoxides such as tert-butyl hydroperoxide, and cumene hydroperoxide. peroxides, dialkyl peroxides such as ditertiary butyl peroxide, dicumyl peroxide,
Examples of azo compounds include alkyl peresters such as tert-butyl perbenzoate and inorganic peroxides such as lead peroxide and manganese peroxide. Examples of azo compounds include 2,2'-azobisisobutyronitrile, 2 , 2'-azobisdimethylvaleronitrile, 2,2'-azobis(2,3,3-trimethylbutyronitrile), and the like. In addition, peroxide can contain cobalt, manganese, and other substances as decomposition accelerators.
It can also be used in combination with salts of heavy metals such as iron and copper, or tertiary amines such as dimethylaniline and dimethylpara-toluidine. When the curable resin composition of the present invention is used as a curable composition that is cured by actinic rays and then heated, the above-mentioned photosensitizer and radicals are added to the mixture of polythiol () and polyene (). Both generators may be added. The amount added is preferably 0.2 to 15 parts by weight per 100 parts by weight of the mixture. As mentioned above, the curable resin composition of the present invention contains polythiol () and polyene () obtained by addition reaction of an epoxy group-containing compound to substituted or unsubstituted allyl alcohol as essential components.
It exhibits improved curability in photocuring reactions and radical curing reactions, and provides cured products with excellent physical properties. The curable resin composition of the present invention can contain antioxidants, polymerization inhibitors, dyes, pigments, plasticizers, adhesives, surfactants, fillers, solvents, reactive diluents, etc., if desired. . The curable resin composition of the present invention has excellent curability,
It provides a cured product with excellent physical properties in terms of hardness, mechanical strength, elongation, flexibility, etc., and when cured by active radiation, there is no curing inhibition caused by oxygen as seen with conventional acrylic systems. It can be used as a paint vehicle, ink vehicle, coating for paper, metal, wood, adhesives, sealants, floor materials, wall materials, etc.
It can be applied to a variety of applications such as leather, iron primers, asbestos coatings, fiber treatment materials, photosensitive resins, and cast products. Production examples and examples are shown below to explain the effects of the present invention. Production example 1 58 g (1 mol) of allyl alcohol and 0.5 g of BF ₃ ether complex were charged into a 500 c.c. four-necked flask (with condenser and dropping funnel) purged with nitrogen, and the reaction temperature was set at 60 to 70°C. 228 g (2 mol) of allyl glycidyl ether was added dropwise over 3 hours while maintaining the temperature. Further, 185 g (2 mol) of epichlorohydrin was added dropwise at the same reaction temperature. The time required for dropping was 2.5 hours.
After the dropwise addition was completed, stirring was continued for 1 hour while maintaining the reaction temperature at 70°C to complete the reaction. After the reaction is completed, the temperature is reduced to 70°C under a reduced pressure of 3 mmHg or less.
Although the mixture was degassed for several hours, almost no low-boiling substances were recovered. The product is a colorless and transparent liquid with a viscosity (25℃) of
It was less than 50cps. This product is referred to as polyene-1. Production Example 2 72 g (1 mol) of crotyl alcohol and 0.5 g of BF ₃ ether complex were charged into a 500 c.c. four-necked flask (with condenser and dropping funnel) purged with nitrogen, and the reaction temperature was increased to 60-60 ml. 70℃
228 g (2 mol) of allyl glycidyl ether was added dropwise over 3 hours while maintaining the temperature. Further, 185 g (2 mol) of epichlorohydrin was added dropwise at the same reaction temperature. The time required for dropping was 2.5 hours.
After the dropwise addition was completed, stirring was continued for 1 hour while maintaining the reaction temperature at 70°C to complete the reaction. After the reaction was completed, the mixture was degassed at 70° C. for 1 hour under a reduced pressure of 3 mmHg or less, but almost no low-boiling point substances were recovered. The product is a colorless and transparent liquid with a viscosity (25℃) of
It was less than 100cps. This product is designated as polyene-2. Production Example 3 A commercially available ethylene oxide adduct of allyl alcohol (commercially available from Nippon Nyukazai Co., Ltd. under the trade name Allyl Glycol) was placed in a nitrogen-substituted four-necked flask (equipped with a condenser and dropping funnel).
According to GCL analysis, 120 g (1.0 mole) of a mixture of 1 mole ethylene oxide adduct 70%, 2 mole adduct 20%, and 3 mole adduct 10%, average molecular weight 120) and 1 g BF ₃ ether complex were prepared. While keeping the reaction temperature at 60-70℃, add 228g (2
mol) of allyl glycidyl ether was added dropwise over 3 hours. Furthermore, at the same reaction temperature, 185g (2 moles)
of epichlorohydrin was added dropwise. The time required for dropping was 2.5 hours. After completing the dropwise addition, adjust the reaction temperature.
Stirring was continued for 1 hour while maintaining the temperature at 70°C to complete the reaction. After the reaction was completed, the mixture was degassed at 70°C for 1 hour under a reduced pressure of 3 mmHg or less, but almost no low-boiling substances were recovered. This product is designated as polyene-3. Examples 1 to 3 A photocuring reaction was carried out using polyenes 1 to 3 of Production Examples 1 to 3. The curable composition was prepared as follows. Pentaerythritol tetrakis thioglycolate to each polyene double bond and SH
0.9 parts by weight of benzophenone as a photosensitizer and 300 ppm of 2,6-ditertiarybutylphenol as a stabilizer were added to 100 parts by weight of this mixture. This curable composition was applied to a tin plate to a film thickness of 50μ,
High pressure mercury lamp (80W/cm x 2, 7.5cm from the light source)
The line speed was varied to determine the maximum speed at which the cured film became tack-free.
The results are shown in Table 1. For comparison, diallyl phthalate (DAP) was carried out in the same manner as in Examples 1-3.

[Table] The results in Table 1 show that the polyenes 1, 2, and
No. 3 indicates that the curing speed is faster than that of conventional allyl polyenes. Further, no inhibition of polymerization by oxygen was observed. Examples 4 to 6 A cured composition was prepared in the same manner as in Examples 1 to 3, applied to a tin plate to a film thickness of 250μ, and irradiated with a high-pressure mercury lamp (30w/cm) at a distance of 25cm for 2 minutes to obtain a cured film. Ta. The physical properties of the obtained cured film were as shown in Table 2. For comparison, diallyl phthalate (DAP) was carried out in the same manner as in Examples 4-6.

[Table] The results in Table 2 show that the polyenes 1, 2, and
No. 3 indicates that the curing speed is faster than that of conventional allyl polyenes. Also, the hardness is the same. Example 7 An example of curing using a radical generator is shown. Polyene-1 obtained in Example 1, 23.6 g
(0.05 mol) in pentaerythritol tetrakis (β-mercaptopropionate) (purity 87.5%)
Mix 20.94g (0.0375 mol) of tert-butyl perbenzoate 0.5 as a radical generator.
g was blended and cured at 120°C for 30 minutes. The pencil hardness of the obtained cured product was HB. Example 8 An example of curing in which heat curing is performed after photocuring is shown. Polyene-3 obtained in Production Example 3, 17.8g
(0.033 mol) in bentaerythritol tetrakis (β-mercaptopropionate) (purity 87.5%)
14.0g (0.025mol), benzophenone 0.3g, tert-butyl perbenzoate 0.4g and 2,
A curable composition was prepared by mixing 300 ppm of 6-ditertiary-butylphenol. This composition
After coating on a 10cm x 10cm x 250μ tin plate and shielding half of the film from light with aluminum foil, a high pressure mercury lamp (30W/
cm) Irradiated for 2 minutes at a distance of 25 cm. The parts that were not shielded from light were cured, but the parts that were shielded from light remained uncured. This product was then placed in a dryer and heated at 130°C for 30 minutes. The coating was uniformly cured both in areas covered with aluminum foil and in areas not covered with aluminum foil.

Claims (1)

[Claims] 1. One or more polythiol compounds () as essential constituents, and a compound having the general formula (In the formula, R is a group selected from a hydrogen atom, a phenyl group, and an alkyl group having 1 to 10 carbon atoms, and may be the same or different. Y is ethylene oxide, propylene oxide, butylene oxide, styrene A ring-opened group formed by cleavage of the carbon-oxygen bond of the epoxy group of one or more epoxy compounds selected from the group consisting of oxide, cyclohexene oxide, epihalohydrin, and allyl glycidyl ether may be used singly or in the form of a block. or randomly arranged groups, provided that Y contains a ring-opened group formed by cleavage of the carbon-oxygen bond of at least one epoxy group of allyl glycidyl ether). 1. A curable resin composition comprising one or more polyene compounds having carbon-carbon double bonds.