JPH0517925B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a resin composition whose cured product exhibits excellent mechanical properties, and an intermediate material for composite materials in which a reinforcing material is impregnated with this resin composition. Conventionally, various resin compositions have been used as matrices for composite materials, but especially in the field of thermosetting resins, in addition to the excellent mechanical properties of the resin itself, especially strength, elongation, and heat resistance, reinforcing materials Epoxy resins have been widely used because they have good adhesion with thermosetting resins and have superior strength development properties for reinforcing materials compared to other thermosetting resins. However, the strength development rate of the reinforcing material is still not sufficient, especially in terms of compressive properties, and there has been a strong desire for improvement. However, when trying to improve the rigidity of the resin itself, the heat resistance increases at the same time, which not only gives more performance than necessary, but also has the disadvantage of significantly reducing elongation.
The situation was such that it could not be used for some purposes. As a result of intensive research into intermediate materials for composite materials that can improve various mechanical properties, mainly compressive properties, the present inventors discovered an additive that can significantly improve the rigidity of the resin itself without reducing its elongation. It was confirmed that the mechanical properties of various composite materials using the epoxy resin-curing agent system as a matrix resin were significantly improved. The present invention is based on the general formula

[Formula] and

[Formula] (In the formula, X is an oxygen atom, a sulfur atom, or a group = N-
R ₅ , R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ may be the same or different and each represents a hydrogen atom, a C ₁ to C ₁₇ saturated or unsaturated aliphatic group, or an alicyclic group. group, aromatic group, heterocyclic group, or R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ together with the nitrogen atom bonded thereto represents a heterocyclic residue, and each of these groups may be substituted with a halogen atom, nitro group, alkoxy group, allyloxy group or acetyl group), a resin composition consisting of an epoxy resin and a curing agent, or a curing accelerator added to this resin composition. It is a resin composition made of Examples of the compound represented by the general formula include the following compounds. Ammonia, methylamine, ethylamine, n-propylamine, n-
Butylamine, isopropylamine, 2-ethylhexyloxypropylamine, 3-ethoxypropylamine, dibutylaminopropylamine,
Aliphatic amines such as diisobutylamine, 3-methoxypropylamine, allylamine, secondary butylamine, isopropanolamine, 2-ethylhexylamine, ethylenediamine, hexamethylenediamine, cyclohexylamine, dicyclohexylamine, aniline, p-aminobenzoic acid, 3 , 4-xylidine, m-xylylenediamine, aromatic amines such as diaminodiphenyl ether, dibenzylamine, benzylamine, acetaldehyde ammonia, 4-aminopyridine,
1-amino-1-methylpiperazine, N-aminopropylmorpholine, bisaminopropylpiperazine, piperazine, 2-pipecoline, piperidine, pyrrolidine, 5-fluorouracil, morpholine, N-methylpiperazine, β-alanine, glycylglycine , glutamic acid, γ-aminobutyric acid, γ-aminocaproic acid, glycine, etc., single or mixed asymmetric ureas or thioureas such as N,N'-dimethylurea, N,N'-
Diphenylthiourea, N-methyl-N'-ethylurea, etc., as well as acetoguanamine, 3-amino-1,2,4-triazole, isocyanuric acid,
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-methylimidazole isocyanur Acid adducts, imidazoles of 2-phenylimidazole isocyanuric acid adducts, 5,5-dimethylhydantoin,
Benzoguanamine-1-methylol-5,5-dimethylhydantoin, melamine, 1,3-diphenylguanidine, di-o-tolylguanidine, 1
-o-tolylbiguanide, N,N'-diphenylthiourea, 2-mercapto-2-imidazoline,
N,N-diethylthiourea, N,N'-dibutylthiourea, N,N'-dilaurylthiourea, etc. Examples of the compound represented by the general formula include the following compounds. epichlorohydrin,
Phenyl glycidyl ether, cyclohexene oxide, ethylene oxide, propylene oxide, butadiene oxide, dimethylpentane dioxide, diglycidyl ether, butanediol diglycidyl ether, ethylene glycol diglycidyl ether, vinyl cyclohexene dioxide, limonene dioxide, bis2,3 -epoxycyclopentene) ether, divinylbenzene dioxide, diglycidyl ether of resorcinol, 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxymethylcyclohexane carboxylate, butyl glycidyl ether, styrene oxide, p-butylphenol Glycidyl ether, cresyl glycidyl ether, glycidyl methacrylate, allyl glycidyl ether, cyclohexane vinyl monoxide, dipentene monoxide, α-binene oxide, 3-(pentadecyl)phenyl glycidyl ether, and the like. The resin composition of the present invention preferably contains 1 to 100 parts by weight of the compound, and 1 to 100 parts by weight of the compound, based on 100 parts by weight of the epoxy resin. If the amount of the compound is less than 1 part by weight, no substantial effect can be exerted. Moreover, if both exceed 100 parts by weight, heat resistance will be significantly reduced. Compounds and substituents R ₁ , R ₂ or R ₃ ,
It is preferable that any combination of R ₄ has a highly rigid structure such as an aromatic group or a heterocyclic group. Examples of epoxy resins include the following compounds. polyglycidyl ethers of diphenylol alkanes such as diphenylolpropane, diphenylolethane, and diphenylolmethane;
Epoxy resins produced by epoxidation of polyglycidyl ethers of polyhydric phenols such as novolak and resol, alicyclic compounds such as cyclohexane, cyclopentadiene, and dicyclopentadiene, such as 3,4-epoxy-6-methyl-cyclohexane - (3,4-epoxy-6-methyl-cyclohexane)-methyl esters of carboxylic acids, poly(epoxyalkyl) ethers of aliphatic polyoxy compounds such as ethylene glycol and glycerin, glycidyl ethers of aromatic and aliphatic carboxylic acids Epoxyalkyl esters of carboxylic acids such as Also, U.S. Patent No. 3390037;
It may be a precondensate of an epoxy resin and a curing agent as described in No. 2970983 and No. 3067170, or it may be a simple mixture. These may be used alone or in combination of two or more. Examples of the curing agent used in the present invention include the following compounds. o-phenylenediamine, m-phenylenediamine, 4,4'-methylenedianiline, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-
Xylene diamine, triethylenetetramine, diethylenetriamine, ituforonediamine, 1,
3-diaminocyclohexanementhanediamine,
Polyamines such as cyanoethylated diethylenetriamine, N-aminoethylpiperazine, methyliminobispropylamine, aminoethylethanolamine, polyetherdiamine, polymethylenediamine, phthalic anhydride, succinic anhydride, maleic anhydride, hexahydrophthalic anhydride , pyromellitic anhydride, benzophenonetetracarboxylic anhydride, trimellitic anhydride, itaconic anhydride, citraconic anhydride, bidecenylsuccinic anhydride, fluorendic anhydride, maleic anhydride adduct of methylcyclopentadiene, methyltetrahydrophthalic anhydride , toluic acid adduct of maleic anhydride,
Cyclopentanetetracarboxylic anhydride, alkylated endoalkylenetetrahydrophthalic anhydride,
Acidic substances having polycarboxylic acid groups, polycarboxylic acid anhydride groups, or mixed groups thereof, such as ethylene glycol bistrimeritate and glycerin tristrimeritate. Examples of curing catalysts include the following compounds. Boron trifluoride complexes such as boron trifluoride monoethylamine complex compound and boron trifluoride piperidine complex compound, 2-methylimidazole, 2-ethyl-4-
Imidazole compounds such as methylimidazole, triphenylphosphitebutanetetracarboxylic acid, 1,8-diaza-bicyclo-(5,4,0)-
Undecene-7, N-(3-chloro-4-methoxyphenyl)-N,N'-dimethylurea, N-(4
-chlorophenyl)3N',N'-dimethylurea, N
-(3-chloro-4-ethylphenyl)-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-(4-methyl-3-nitrophenyl)-N', Urea compounds such as N'-dimethylurea, etc. The combination and quantitative ratio of the epoxy resin and the curing agent are preferably close to the generally stoichiometric ratio, and when a curing catalyst is included, it is further preferable to use the curing agent at a slightly lower stoichiometric ratio. Further, when the compound has a functional group that can contribute to curing, it is preferable to reduce the amount of the curing agent depending on the functional group in the compound. Compounds and curing agents are mainly effective for epoxy resins with amine-based curing agents, but they also exhibit some effect on acid anhydride-based curing agents. It is not clear why these additives work effectively to improve the rigidity of epoxy resins, but there is a relatively strong bond between the hydroxyl groups generated when the epoxy group opens and the hydroxyl groups generated when the compound reacts with the compound during curing. This is thought to be due to the formation of hydrogen bonds. When producing an intermediate material for composite materials using the resin composition of the present invention, examples of reinforcing materials include glass fiber,
In addition to inorganic fibers such as carbon fibers, boron fibers, and silicone carbide fibers, chop-shaped, yarn-shaped, tape-shaped, sheet-shaped, knitted,
Examples include mat-like materials, paper-like materials, asbestos, mica, talc, etc., and these materials can be used alone or in combination of two or more. Depending on the application, pigments,
It can be used in combination with dyes, stabilizers, plasticizers, lubricants, tar, asphalt, other reinforcing materials, etc. The content of the reinforcing material is preferably 5 to 80% by volume.
Further, thermosetting resins and thermoplastic resins other than epoxy resins can be used in combination. Since the resin composition of the present invention contains the compound and, its bending strength and elastic modulus are significantly improved, and its rigidity is also excellent. Further, by impregnating a reinforcing material with this resin composition, an intermediate material for a composite material with particularly improved rigidity can be obtained. This intermediate material can also be used in new fields such as aircraft. Examples 1 to 12 and Comparative Examples 1 to 7 10 phr each of the compounds shown in the table below
The mixture was mixed with 100 parts by weight of an epoxy resin (Epicoat 828, manufactured by Ciel Chemical Co., Ltd.) at a ratio of 100% by weight, and stirred for 10 minutes at a temperature of 60°C to mix uniformly. Next, 30 parts by weight of diaminodiphenylmethane was added to this system and mixed uniformly at 60°C for 10 minutes to obtain a resin composition (A). Using this resin composition (A), 90℃ × 1
A resin plate was molded under curing conditions of 1 hour and 130°C, and a bending test was conducted. The results are shown in the table below. Further, a sheet prepreg was prepared by uniformly impregnating carbon fibers with the resin composition (A) and pulling them in one direction. This prepreg is laminated and molded at 90°C.
A composite was prepared by curing under the conditions of 1 hour x 1 hour and 1 hour x 130°C at 7 kg/cm ² . The measurement results of the flexural strength, flexural modulus, flexural elongation, and interlaminar shear strength of this composite are also shown in the table below.
From this, it is known that the resin composition of the present invention significantly improves the physical properties of resin plates, and also significantly improves the mechanical properties of composite properties.

【table】

【table】

Claims (1)

[Claims] 1. General formula [Formula] and [Formula] (wherein X is an oxygen atom, a sulfur atom, or a group=N-
R ₅ , R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ may be the same or different and each represents a hydrogen atom, a C ₁ to C ₁₇ saturated or unsaturated aliphatic group, or an alicyclic group. group, aromatic group, heterocyclic group, or R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ together with the nitrogen atom bonded thereto represents a heterocyclic residue, and each of these groups may be substituted with a halogen atom, nitro group, alkoxy group, allyloxy group or acetyl group), a resin composition consisting of an epoxy resin and a polyamine-based or acidic substance-based curing agent, or this resin composition A resin composition containing a curing accelerator.