JPS6121490B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a curable resin composition. More specifically, the weight loss during curing is small,
Moreover, the present invention relates to a curable resin composition whose cured product has excellent heat resistance. Unsaturated polyester resins made of unsaturated polyester and polymerizable vinyl monomers and epoxy (meth)acrylate resins made of epoxy (meth)acrylates and polymerizable vinyl monomers have excellent curability, mechanical properties, and chemical properties. Due to its excellent properties, it is used in cast products, laminated products, molding materials,
It is widely used in paints and electrical insulation varnishes. However, when unsaturated polyester resins and epoxy (meth)acrylate resins are cured, some of their components volatilize and their weight decreases, and the resulting cured products have insufficient heat resistance for use at high temperatures. There is a drawback. In order to improve these drawbacks, terephthalic acid and isophthalic acid are used as the acid component of unsaturated polyester, and diallyl phthalate, diallylisophthalate, and triaryl phthalate are used instead of styrene, which is generally used as a polymerizable vinyl monomer. Methods using lucyanurate, triallylisocyanurate, etc. have been proposed, but the effects are not sufficient. A method of introducing imide groups into the molecular skeleton of unsaturated polyester has also been proposed, but introducing imide groups into the molecular skeleton significantly reduces compatibility with polymerizable vinyl monomers such as styrene. . In view of the current situation, the present inventors have conducted intensive research and found that a curable resin composition consisting of a specific polymerizable compound, unsaturated polyester, and/or epoxy (meth)acrylate does not have the above-mentioned problems. They discovered that the problem could be solved all at once, and completed the present invention. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a curable resin composition which exhibits a small weight loss during curing and which provides a cured product with excellent heat resistance. That is, the curable resin composition of the present invention has the general formula (However, in the formula, R ₁ and R ₂ each represent hydrogen or a methyl group, and may be the same or different.) Polymerizable compound (A) represented by the following and unsaturated polyester and/or Or, it is characterized by containing epoxy (meth)acrylate (B). The polymerizable compound (A) used in the present invention is represented by the above general formula, and is 2-tetrahydrophthalimidoethyl acrylate, 2-tetrahydrophthalimidoethyl methacrylate, or a methyl group-substituted product thereof. One type or two or more types can be used from the group. Such a polymerizable compound (A) is preferably used in an amount of 30 to 80% by weight based on the resulting curable resin composition. If the amount is less than 30% by weight, the resulting cured product of the curable resin composition will not have sufficient heat resistance, and if it is used in an amount exceeding 80% by weight, the resulting cured product will tend to become brittle, which is not preferred. As the unsaturated polyester used in the present invention, those commonly used in the art can be used. That is, it is produced by using an unsaturated dibasic acid as an essential acid component and using a saturated dibasic acid or an aliphatic monobasic acid as necessary, and a polyhydric alcohol as an essential alcohol component and using a monohydric alcohol as necessary. can be used. Among these unsaturated polyesters, in the present invention, those derived using α,β-unsaturated dibasic acids and aliphatic monobasic acids as acid components and tris (2-hydroxy) as polyhydric alcohol components are used. It is preferable to use ethyl isocyanurate. Then, an unsaturated polyester derived by always using an α,β-unsaturated dibasic acid and an aliphatic monobasic acid as an acid component and always using tris(2-hydroxyethyl) isocyanurate as a polyhydric alcohol component, This is particularly preferred in the present invention. Examples of such aliphatic monobasic acids include soybean fatty acids, tall oil fatty acids, rice bran fatty acids, and tung oil fatty acids. Epoxy (meth)acrylate refers to a reaction product of an epoxy compound having two or more epoxy groups in one molecule and an unsaturated dibasic acid such as acrylic acid or methacrylic acid. Examples of epoxy compounds include bisphenol A-based epoxy compounds (for example, "Araldite GY-250" manufactured by Ciba Corporation), novolac-based epoxy compounds (for example, "Araldite GY-250" manufactured by Ciba Corporation),
"Epicote 154"), epoxy compounds derived from fatty cyclic compounds such as cyclohexane and dicyclopentadiene (e.g. "Titsonox
221''), etc. In obtaining the curable resin composition of the present invention from the polymerizable compound (A) and the unsaturated polyester and/or epoxy (meth)acrylate (B), the polymerizable Compound (A) and unsaturated polyester and/or epoxy (meth)acrylate (B) may be mixed and dissolved in any order and may be mixed and dissolved by any method. Such mixing order and mixing method The present invention is not limited by this. The curable resin composition of the present invention essentially contains a polymerizable compound (A) and an unsaturated polyester and/or an epoxy (meth)acrylate (B). In order to adjust the viscosity and improve workability, other polymerizable vinyl monomers may be added and used. Examples of such other polymerizable vinyl monomers include styrene, vinyltoluene, Divinylbenzene, N-vinyl-2-pyrrolidone, N-vinylpyridine, diallyl phthalate, diallyl isophthalate, triallyl cyanurate, triallyl isocyanurate, methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, isodecyl meth acrylate,
Benzyl acrylate, furfuryl acrylate, lauryl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol Dimethacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol methacrylate, 1,6
-hexane diacrylate, 1,6-hexane dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, and the like. Additionally, additives commonly used in this technical field, such as silicone-based or acrylic leveling agents, thixotropic agents such as anhydrous silicic acid fine particles, fillers such as calcium carbonate, silica powder, clay, glass powder, mica, etc., are also effective. It can be used for The curable resin composition of the present invention thus obtained has a small weight loss upon curing, and the coating film and molded product obtained by curing have excellent heat resistance. It also has excellent adhesion to the base material. When using the curable resin composition of the present invention, curing can be carried out using a polymerization initiator commonly used in the art or by irradiation with ultraviolet rays. As a polymerization initiator, benzoyl peroxide, lauroyl peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, di-t
-amyl peroxide, dicumyl peroxide, pt-butyl peroxybenzoate, and the like. It is also possible to use these polymerization initiators together with organic metal salts such as cobalt octenoate, cobalt naphthenate, manganese octenoate, vanadium octenoate, and organic amines such as N,N-dimethylaniline as accelerators.
A photosensitizer can be used during ultraviolet irradiation, and examples of such photosensitizers include benzoin, benzoin ethyl ether, benzoin isopropyl ether, and the like. or,
A polymerization initiator and ultraviolet irradiation can also be used together. Hereinafter, the present invention will be explained in more detail with reference to Examples. In addition, "parts" in the examples shall mean "parts by weight." Reference Example 1 In a flask, 193 g (1 mol) of N-(2-hydroxyethyl)-tetrahydrophthalimide, 195 g of toluene, 0.5 g of hydroquinone, and 80 g of acrylic acid.
(1.1 mol) and 0.8 g of para-toluenesulfonic acid were added to carry out an esterification reaction at 90 to 110°C under a stream of air, and the reaction was stopped when 18 ml of produced water had been distilled out. After the reaction is complete, neutralize with NaOH aqueous solution to pH 6-7.
After separating the aqueous layer and toluene layer, toluene was distilled off from the toluene layer by vacuum distillation to obtain the desired 2-tetrahydrophthalimidoethyl acrylate (bp 161-165℃/0.29mmHg, hereinafter referred to as imide acrylate (1)). call). This imide acrylate (1) had no odor and was normally in a liquid state. Reference Example 2 In Reference Example 1, 193 g of N-(2-hydroxyethyl)-tetrahydrophthalimide was replaced with N.
2-(methyltetrahydrophthalimide) was prepared in the same manner as in Reference Example 1 except that 217 g of -(2-hydroxyethyl)-methyltetrahydrophthalimide was used.
Ethyl acrylate (hereinafter referred to as imide acrylate)
(2)) was obtained. This imide acrylate (2) also had no odor and was normally plate-like. Example 1 0.3 mol of isophthalic acid and 0.3 mol of adipic acid in the reactor
mol, maleic anhydride 0.4 mol and dipropylene glycol 1.05 mol, and under nitrogen flow, 180 ~
A dehydration condensation reaction was carried out at 220°C to obtain an unsaturated polyester with an acid value of 31. The number average molecular weight determined by gel permeation chromatography (hereinafter referred to as GPC) was 1800. 100 parts of the imide acrylate (1) obtained in Reference Example 1 and 0.02 part of hydroquinone were mixed and dissolved in 100 parts of this unsaturated polyester at 80°C to obtain a transparent curable resin composition (1). After thoroughly dissolving 0.2 parts of cobalt octenoate in 100 parts of this curable resin composition (1), 1 part of pt-butyl peroxybenzoate was added and mixed, and 1 g of this was poured into a 60 mm diameter aluminum dish and thinly spread. It was spread and cured at 130°C for 1 hour, and then further cured at 150°C for 4 hours to obtain a cured coating film. The weight loss during curing was measured and shown in Table 1. Next, the weight of the obtained cured coating film is set as 100,
The weight of the sample when it was left in a constant temperature bath at 250°C was measured after 1 day and 10 days to examine its heat resistance. The results are shown in Table 1. Comparative Example 1 A resin composition was obtained in the same manner as in Example 1 except that 100 parts of styrene was used in place of 100 parts of imide acrylate (1). (Hereinafter referred to as Comparative Resin Composition (1).) Regarding this Comparative Resin Composition (1), the weight loss during curing and the heat resistance of the cured coating film were investigated in the same manner as in Example 1. The results are shown in Table 1. It was shown to. Example 2 0.45 mol of tetrahydrophthalic anhydride in the reactor,
Adipic acid 0.25 mol and diethylene glycol
1.03 mol was charged and a dehydration condensation reaction was carried out at 180 to 230°C under a nitrogen stream, and when the acid value reached 10.
The mixture was cooled to 150°C, then 0.3 mol of maleic anhydride was added, and the dehydration condensation reaction was further advanced to obtain an unsaturated polyester with an acid value of 25. The number average molecular weight by GPS was 1900. 100 parts of imide acrylate (1), 40 parts of diethylene glycol dimethacrylate, and 0.024 parts of hydroquinone were mixed and dissolved in 100 parts of this unsaturated polyester to obtain a transparent curable resin composition (2) with almost no odor. This curable resin composition (2) 100
After sufficiently dissolving 0.02 part of cobalt octenoate in 1 part, 1 part of pt-butyl peroxybenzoate was mixed and dissolved, and the weight loss during curing and the heat resistance of the cured coating film were examined in the same manner as in Example 1. Ta. The results are shown in Table 1. Further, the above-mentioned curable resin composition (2) to which cobalt octenoate and pt-butyl peroxybenzoate were added was cast and cured to obtain a cast plate with a thickness of 3 mm. The weight of this cast plate was measured when it was left in a constant temperature bath at 250°C, and the heat resistance was investigated. The results are shown in Table 1. Example 3 1 mole of soybean aliphatic and 0.5 isophthalic acid in the reactor
1 mole of trimethylolpropane and 0.1 mole of ethylene glycol were charged, and the acid value was dehydrated at 180 to 220°C to give an acid value of 10. After cooling to 150°C, 0.1 mole of ethylene glycol and 0.5 mole of fumaric acid were charged to give an acid value of 180 to 190. Acid value 25 after dehydration reaction at ℃
An unsaturated polyester was obtained. 100 parts of imide acrylate (1), 50 parts of diethylene glycol dimethacrylate, and 0.02 part of hydroquinone were mixed and dissolved in 100 parts of this unsaturated polyester to obtain a transparent curable resin composition (3) with almost no odor. This curable resin composition (3) 100
After dissolving 1 part of pt-butyl peroxybenzoate in 1 part, the weight loss during curing and the heat resistance of the cured coating film were examined in the same manner as in Example 1. The results are shown in Table 1. Further, the curable resin composition (3) in which the above-mentioned pt-butyl peroxybenzoate was dissolved was applied to a tin plate with a bar coater to a thickness of 30μ, and cured at 150°C for 1 hour to form a cured coating. I got it. This coating film has sufficiently dried and hardened, and has been passed the goblin test (JIS D
0203) was 100/100, indicating excellent adhesion. The results of the bending test (JIS K 5400) were also good. Example 4 1 mole of soybean aliphatic and 0.5 isophthalic acid in the reactor
1 mole of tris(2-hydroxyethyl)isocyanurate and 0.1 mole of ethylene glycol were dehydrated and condensed at 210°C under a nitrogen stream. When the acid value reached 10, the reaction was stopped, and the mixture was cooled to 150°C to produce 0.1 mol of ethylene glycol. Mol and fumaric acid 0.5
The mixture was further dehydrated and condensed at 180 to 190°C to obtain an unsaturated polyester having an acid value of 22. The number average molecular weight by GPC was 1950. 60 parts of imide acrylate (1), 40 parts of diethylene glycol dimethacrylate, and 0.02 part of hydroquinone were mixed and dissolved in 100 parts of this unsaturated polyester to obtain a transparent curable resin composition (4) with almost no odor. After dissolving 1 part of pt-butyl peroxybenzoate in 100 parts of this curable resin composition (4), the weight loss during curing and the heat resistance of the cured coating were examined in the same manner as in Example 1. Ta. The results are shown in Table 1. In addition, the curable resin composition (4) in which the above pt-butyl peroxybenzoate was dissolved was applied to a tin plate with a bar coater to a thickness of 30μ, and cured at 150°C for 1 hour to form a cured coating. I got it. This coating film was sufficiently dried and cured, and the result of the cross-cut test conducted in the same manner as in Example 3 was 100/100, indicating excellent adhesion, and the results of the bending test were also good.
Further, the curable resin composition (4) containing the above polymerization initiator was cast and cured to obtain a cast plate with a thickness of 3 mm. The heat resistance of this casting plate was examined at 250°C in the same manner as in Example 2. The results are shown in Table 1. Comparative Example 2 A transparent resin composition with almost no odor was obtained in the same manner as in Example 4, except that 60 parts of diallylisophthalate was used in place of 60 parts of imide acrylate (1). (Hereinafter, referred to as Comparative Resin Composition (2).) Regarding this Comparative Resin Composition (2), the weight loss during curing and the heat resistance of the cured coating film were examined in the same manner as in Example 4. The results are shown in Table 1. Example 5 A transparent curable resin composition with almost no odor was prepared by mixing and dissolving 150 parts of imide acrylate (1), 50 parts of diethylene glycol dimethacrylate, and 0.01 part of hydroquinone in 100 parts of the unsaturated polyester obtained in Example 4. I got item (5). One part of pt-butyl peroxybenzoate was dissolved in 100 parts of this curable resin composition (5), and the weight loss during curing and the heat resistance of the cured coating film were examined in the same manner as in Example 1. The results are shown in Table 1. Example 6 Bisphenol type epoxy resin with epoxy equivalent weight 185 (manufactured by Ciba, “Araldite GY-2500”) 370
176 parts of methacrylic acid, 0.1 part of hydroquinone and 2.0 parts of triethylamine were charged into a reactor.
The reaction was carried out at 110° C. for 5 hours while introducing air, and the reaction was terminated when the acid value reached 7 to obtain epoxy methacrylate. 16.4 parts of this epoxy methacrylate, 13.6 parts of diallyl phthalate, and 70 parts of the imide acrylate (2) obtained in Reference Example 2 were mixed to obtain a transparent curable resin composition (6) with almost no odor. One part of pt-butyl peroxybenzoate was dissolved in 100 parts of this curable resin composition (6), and the weight loss during curing and the heat resistance of the cured coating film were examined in the same manner as in Example 1. The results are shown in Table 1. Example 7 An odorless and transparent curable resin composition (7) was obtained in the same manner as in Example 5 except that imide acrylate (2) was used instead of imide acrylate (1). Regarding this cured resin composition (7), the weight loss upon curing and the heat resistance of the cured coating film were examined in the same manner as in Example 1. The results are shown in Table 1. Example 8 The weight loss during curing was measured in the same manner as in Example 5 except that benzoyl peroxide was used instead of pt-butyl peroxybenzoate. The results are shown in Table 1. Example 9 Curable resin composition (4) obtained in Example 4 100
After dissolving 0.2 parts of cobalt octenoate and 2 parts of benzoin ethyl ether in the solution, it was applied to a glass plate to form a coating film of approximately 100μ, and irradiated under an ultraviolet lamp (800V) at a distance of 15cm for 5 minutes. A sufficiently cured coating film was obtained.

[Table] As is clear from the results shown in Table 1, the curable resin composition of the present invention had a small weight loss during curing, and the heat resistance of the coating film and molded product obtained by curing was also excellent. It is something.

Claims (1)

[Claims] 1. General formula (However, in the formula, R ₁ and R ₂ each represent hydrogen or a methyl group, and may be the same or different.) Polymerizable compound (A) represented by: and unsaturated polyester and/or epoxy A curable resin composition containing (meth)acrylate (B). 2. The curable resin composition according to claim 1, wherein the unsaturated polyester is derived using an acid component that necessarily contains an α,β-unsaturated dibasic acid and an aliphatic monobasic acid. . 3. The curable resin composition according to claim 1 or 2, wherein the unsaturated polyester is derived using a polyhydric alcohol component that necessarily contains tris(2-hydroxyethyl)isocyanurate. . 4. Claims 1 and 2, wherein the epoxy (meth)acrylate is derived from an epoxy compound having a bisphenol skeleton as a component.
The curable resin composition according to item 1 or 3.