JPH04489B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD This invention relates to additives for epoxy resins that provide excellent mechanical properties. [Background Art] Epoxy resins have been widely used in adhesives and structural materials due to their excellent mechanical properties (particularly strength, elongation, and heat resistance), and as insulating materials due to their excellent electrical properties. Ta. However, conventional epoxy resins generally have the disadvantage that when trying to improve their rigidity, they also increase their heat resistance, giving them more performance than necessary and significantly reducing their elongation, making them unusable in some applications. The situation suited me. [Object of the Invention] As a result of intensive study in view of the above, the present inventors found that
We have discovered an additive for epoxy resins that can significantly improve rigidity without sacrificing elongation. [Structure of the invention] That is, the present invention provides general formula (1) This is an additive for epoxy resins whose main component is the compound shown below. Here, R ₁ , R ₂ , R ₃ , and R ₄ are hydrogen, a C ₁ to _{C 17} saturated or unsaturated aliphatic group, an alicyclic group, an aromatic group,
Heterocyclic group, a heterocyclic residue excluding the nitrogen bonded to R ₁ , R ₂ , R ₃ , R ₄ , which is further substituted with a halogen group, nitro group, alkoxy group, allyloxy group, acetyl group, etc. R ₁ , R ₂ , R ₃ and R ₄ may be the same or different. X is oxygen, sulfur atom or N- _R5 group,
R ₅ is hydrogen, a C ₁ to _{C 17} aliphatic group, alicyclic group, aromatic group, or heterocyclic group, and is further substituted with a halogen group, nitro group, alkoxy group, allyloxy group, acetyl group, etc. Good too. The compound of general formula (1) is usually a compound represented by general formula (2) and a compound represented by general formula (3) Ethanolamine, ethanolaniline, N,N-diethylethanolamine, N,N-dimethylethanolamine, aminoethylethanolamine, N-methyl-N,N-diethanolamine, N,N Examples include formic acid, acetic acid, propionic acid, benzoic acid, and amides of these thio and dithiocarboxylic acids, such as -diisopropylethanolamine, N,N-dibutylethanolamine, and N-methylethanolamine. Compounds represented by general formula (2) include methylamine, ethylamine, n-propylamine, n-butylamine, isopropylamine, 2-ethylhexyloxypropylamine, 3-ethoxypropylamine, di-2-ethylhexylamine, dibutylamino Propylamine, diisobutylamine, 3-methoxypropylamine, allylamine, sec-butylamine, isopropanolamine,
2-ethylhexylamine, ethyleneamine, hexamethylenediamine, cyclohexylamine,
Aliphatic amines such as dicyclohexylamine, aromatic amines such as aniline, P-aminobenzoic acid, 3,4-xylidine, m-xylylene diamine, diaminodiphenyl ether, dibenzylamine, benzylamine, acetaldehyde ammonia, 4-aminopyridine, 1-amino-methylpiperazine, N-aminopropylmorpholine, bisaminopropylpiperazine, piperazine, 2-pipecoline, piperidine, pyrrolidine, 5-fluorouracil, N-methylpiperazine, morpholine, β-alanine, Amino acids such as glycylglycine, glutamic acid, γ-aminolactic acid, γ-aminocaproic acid, glycine, amines, fatty acids such as formic acid, acetic acid, propionic acid, aromatic acids such as benzoic acid, or their monothio or dithiocarboxylic acids. Amide or acetoguanamine, 3
-amino-1,2,4-triazoleisocyanuric acid, 2-methylimidazole, 2-ethyl-4
-Methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole, 2,4-diamino-6-
[2'-Methylimidazolyl-(1')]-ethyl-S-
Triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-S-triazine, 2,4-diamino-6-[2'-ethyl-
4-Methylimidazolyl-(1')]-ethyl-S-
Triazine, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-
4,5-dihydroxymethylimidazole, 2-
Methylimidazole isocyanuric acid, 2
- Imidazoles such as phenylimidazole and isocyanuric acid adducts, 5,5-dimethylhydantoin benzoguanamine, 1-methylol-5,
5-dimethylhydantoin, melamine, 1,3-
Diphenylguanidine, di-O-tolylguanidine, 1-O-tolyl biguanide, and the like can be mentioned. Compounds represented by general formula (3) include epichlorohydrin, phenylglycidyl ether, cyclohexene oxide, ethylene oxide, propylene oxide, butadiene oxide, dimethylpentane oxide, dicrycidyl ether, butanediol diglycidyl ether, ethylene glycol, diglycidyl ether, Vinyl cyclohexene dioxide, limonene dioxide, bis(2,3-epoxycyclopentyl) ether, divinylbenzene dioxide, diglycidyl ether of resorcinol, 2-glycidylphenyl glycidyl ether, 3,4-epoxy-6-
Methyl cyclohexyl methyl, 3,4-epoxymethyl cyclohexane carboxylate, butyl glycidyl ether, styrene oxide, P-
Butylphenol glycidyl ether, gleyl glycidyl ether, glycidyl methacrylate, allyl glycidyl ether, cyclohexene vinyl monooxide, dipentene monooxide, α-binene oxide, 3 (pentadecyl)
Examples include low molecular epoxy compounds such as phenyl glycidyl ether. The reaction between the compound represented by the general formula (2) and the compound represented by the general formula (3) can be carried out without a solvent or in an organic solvent such as aromatic solvents such as benzene and toluene, aliphatic solvents such as hexane and ligroin, carbon tetrachloride, chloroform, etc. from room temperature to 180°C in a halogen-based solvent such as dioxane or an ether-based solvent such as tetrahydrofuran.
The reaction may be carried out with stirring at a temperature up to The stoichiometry between the epoxy group and the NH group at this time may be in the range of 1/10 to 10/1, but is more preferably in the range of 1/1.5 to 1.5/1. Although there is no particular restriction on the method of reaction between general formula (2) and general formula (3), it is desirable to proceed with the reaction while adding (3) into (2). After the reaction is completed, it may be determined by quantifying the epoxy group in the case of excess amine, or by quantifying the NH group in the case of excess epoxy, but it is not necessary that each functional group has disappeared. The additive of the present invention can be used by adding 2 to 150 parts by weight to 100 parts by weight of the combination system of epoxy resin, curing agent, and/or curing catalyst, but it can be used by adding 2 parts by weight. If it is less than that, it is not preferable because no substantial effect can be achieved.
If it exceeds 150 parts by weight, it is not preferable because it significantly reduces heat resistance. Among the above compound groups, R ₁ , R ₂ , or R ₃ ,
It is desirable to have a highly rigid structure such as an aromatic ring or a heterocyclic ring in any combination of R ₄ . The molecular weight of compound (1) is preferably up to 5,000. This is because when this value is exceeded, the resin generally becomes solid, becomes difficult to handle, and cannot effectively improve the rigidity of the resin used for other purposes. The epoxy resin used in combination with additives in the present invention refers to all known epoxy resins, such as diphenylolpropane, diphenylolethane, diphenylolmethane,
Epoxy resins produced by epoxidation of polyglycidyl ethers of diphenyloalkanes, polyglycidyl ethers of polyhydric phenols such as novolak or resol, alicyclic compounds such as cyclohexane, cyclopentadiene, and cyclopentadiene; For example, (3,4-epoxy-6-methyl-cyclohexane) methyl ester of 3,4-epoxy-6-methyl-cyclohexane-carboxylic acids, or poly(epoxyalkyl) of aliphatic polyoxy compounds such as ethylene glycol and glycerin. It refers to ethers, or epoxyalkyl esters of carboxylic acids such as glycidyl esters of aromatic and aliphatic carboxylic acids. Also USP3390037, USP2970983,
It may be a precondensate of an epoxy resin and a curing agent as described in each specification of USP 3067170, or it may be a simple mixture. These may be used alone or in combination of two or more. The curing agent used in the present invention includes O-phenylenediamine, m-phenylenediamine, 4,4'-
Aromatic polyamines such as methylene dianiline, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-xylenediamine, triethylenetetramine, diethylenetriamine, isophoronediamine, 1,3-diaminocyclohexane, Polyamines such as aliphatic polyamines such as menthanediamine, cyanoethylated diethylenetriamine, N-aminoethylpiperazine, methyliminobispropylamine, aminoethylethanolamine, polyetheramine, polymethylenediamine, phthalic anhydride, succinic anhydride, anhydride Maleic acid, hexahydrophthalic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, trimellitic anhydride, itaconic anhydride, citraconic anhydride, dodecenylsuccinic anhydride, fluorendic anhydride, maleic anhydride of methylcyclopentadiene Polycarboxylic acid groups such as adducts, methyltetrahydrophthalic anhydride, maleic anhydride, toluic acid adducts, cyclopentanetetracarboxylic anhydride, alkylated endoalkylenetetrahydrophthalic anhydride, ethylene glycol bistrinuritate, glycerin tristrimethate, etc. , acidic substances having a polycarboxylic acid anhydride group or a mixed group thereof, hydrazides such as isophthalic acid, dihydrazide, adipic acid dihydrazide, and sebacic acid dihydrazide, polyamide amines, dicyandiamide ketimine, and the like. As curing catalysts, boron trifluoride complexes such as boron trifluoride monoethylamine complex compounds and boron trifluoride piperidine complex compounds, imidazole compounds such as 2-methylimidazole and 2-ethyl 4-methylimidazole, triphenylphosphite, and butane are used. Tetracarboxylic acid, 1,8 diazabicyclo-(5,4,0)-undecene-7, N-(3-chloro-4-methoxyphenyl)-N',N-dimethylurea, N-(4- chlorophenyl)-N′,
N'-dimethylurea, N-(3-chloro-4ethylphenyl)-N',N'-dimethylurea, N-
(3-chloro-4-methylphenyl)-N',N'-
Dimethylurea, N-(3,4-dichlorophenyl)-N',N-dimethylurea, N-(4-ethoxyphenyl)-N',N'-dimethylurea, N-
Examples include urea compounds such as (4-methyl-3nitrophenyl)N',N'-dimethylurea. The combination and quantitative ratio of the above-mentioned epoxy resin and curing agent should be approximately stoichiometric.
When a curing catalyst is included, it is further desirable to use the curing agent in a slightly lower stoichiometric amount. Furthermore, if the additive contains a functional group that can contribute to curing, it is desirable to reduce the amount of curing agent depending on the functional group in the additive. This additive is mainly effective for epoxy resins with amine-based curing agents, but it also exhibits some effect on acid anhydride-based curing agents. The reason why these additives work effectively to improve the rigidity of epoxy resins is not clear, but it is thought to be because they form relatively strong hydrogen bonds with the hydroxyl groups generated as the epoxy group opens. The epoxy resin composition containing the additive of the present invention is cured at room temperature or by heating, and the cured product achieves improved rigidity without significantly sacrificing elongation, and can be used as adhesives, cast products, molding materials, etc. It can be used as a laminated material, paint, etc. Depending on the purpose, pigments, dyes, stabilizers, plasticizers, lubricants, tar, asphalt, glass fibers,
Chops, yarns, tapes, and sheets made of inorganic fibers such as carbon fiber, boron fiber, and silicone carbide fiber, as well as organic fibers such as poly-P-phenylene terephthalamide, poly-P-benzamide, and polyamide hydrazide. It is also possible to use a single material, a knitted material, a mat-like material, a paper-like material, asbestos, mica, talc, etc., or a mixture of two or more thereof. It is also possible to use thermosetting polymers and thermoplastic polymers other than epoxy resins. [Example] The present invention will be specifically explained below with reference to Examples. Examples 1 to 23, Comparative Examples 1 to 3 As shown in Table 1, Compound (2) and Compound (3) shown in Table 1 were mixed and reacted at 150°C for 3 hours with stirring. obtained the drug. The target compound was identified using proton NMR by confirming that the peak due to the hydrogen atom attached to the nitrogen atom had disappeared. Next, add the above synthetic additive or compound (1) to 100 parts by weight of epoxy resin, Epicoat 828 (manufactured by Ciel Chemical).
30 parts by weight were mixed and stirred for 10 minutes at a temperature of 60°C to mix uniformly. Then, 30 parts by weight of DDM was added to this system and 60
The mixture was uniformly mixed at ℃ for 10 minutes to obtain a resin composition (A). This resin composition (A) was coated at 90°C x 1 using the cell cast method.
A resin plate was molded under curing conditions of +130°C x 1 hour and a water resistance test was conducted. The water resistance test was conducted by immersing the sample in water at 60°C for one week, and then measuring the bending strength and flexural modulus. The results are shown in Table 1. Further, a sheet-like prepreg was made by uniformly impregnating carbon fibers with the resin composition (A) and pulling them in one direction. This prepreg is layered and molded at 90℃ x 1 hour + 130℃ x 1 hour, 7Kg/cm ²
A composite was created by curing under the following conditions. Table 1 also shows the measurement results of the flexural strength, flexural modulus, tensile elongation, and interlaminar shear strength of the composite. As shown in Table 1, the physical properties of the resin plate are greatly improved by adding the additive of the present invention, and the system to which the additive of the present invention is added is significantly superior in terms of water resistance. There was found. It was also found that the mechanical properties of components were significantly improved.

【table】

【table】

〔Effect of the invention〕

By adding the additive of the present invention, it is possible to significantly improve the bending strength and elastic modulus of the epoxy resin and to make it excellent in rigidity.

Claims (1)

[Claims] 1. General formula (R ₁ , R ₂ , R ₃ , R ₄ are hydrogen, C _1-17 saturated or unsaturated aliphatic group, alicyclic group, aromatic group, heterocyclic group, or R ₁ , R ₂ , R ₃ , R ₄ is a heterocyclic residue excluding the bonded nitrogen, and these groups may be substituted with a halogen group, nitro group, alkoxy group, allyloxy group or acetyl group. R ₁ , R ₂ , R ₃ , _R4
may be the same or different. X is oxygen, sulfur or N- _R5 group, _R5 is hydrogen, _C1-17 aliphatic group,
An additive for epoxy resins, which is an alicyclic group, an aromatic group, or a heterocyclic group, and these groups may be substituted with a halogen group, a nitro group, an alkoxy group, an allyloxy group, or an acetyl group. 2. The additive for epoxy resins according to claim 1, wherein [Formula] is obtained by a reaction between [Formula] and [Formula].