WO2000053654A1

WO2000053654A1 - Epoxy resin composition, epoxy resin composition for fiber-reinforced composite, and fiber-reinforced composite containing the same

Info

Publication number: WO2000053654A1
Application number: PCT/JP2000/001462
Authority: WO
Inventors: Toshiya Kamae; Hiroki Oosedo; Shunsaku Noda; Shinji Kouchi; Ryuji Sawaoka
Original assignee: Toray Industries, Inc.
Priority date: 1999-03-11
Filing date: 2000-03-10
Publication date: 2000-09-14

Abstract

An epoxy resin composition which has a low viscosity and is excellent in infiltration into reinforcing fibers; and a composite having excellent mechanical properties. The composition comprises a polyfunctional aromatic epoxy resin and, compounded therewith, an aromatic amine compound and/or an alicyclic amine compound. It is characterized by having a viscosity at 25°C of 1 to 1,500 mPa. s as measured at 5 minutes after a main ingredient comprising the epoxy resin is mixed at 25°C with a hardener comprising the amine compound(s) and by satisfying the following equation (1): Tg ≥Tc + 20 - k x (Tc - 90) wherein k is 0 when 60≤Tc∫90, and is 0.35 when 90≤Tc≤200; Tc is the maximum temperature (°C) during curing (60≤Tc≤200); tc is the retention time (min) at the maximum temperature (1≤tc≤120); and Tg is the glass transition temperature of the epoxy resin composition at the time when the period tc (min) has passed at Tc (°C).

Description

Technical Field The present invention relates to an epoxy resin composition, an epoxy resin composition for a fiber-reinforced composite material, and a fiber-reinforced composite material having the same. More specifically, the fiber reinforced composite material obtained after curing has low viscosity and easy handling at the time of impregnation into the reinforcing fiber, and has excellent mechanical properties such as heat resistance and compressive strength. The present invention relates to an epoxy resin composition for a composite material and a fiber-reinforced composite material obtained therefrom. BACKGROUND ART Fiber reinforced composite materials composed of reinforced fibers and a matrix resin are lightweight and have excellent mechanical properties, and are therefore widely used in aerospace, sports, and general industrial fields. .

Thermosetting resin is mainly used as the matrix resin of the fiber-reinforced composite material. Among them, epoxy resins having excellent heat resistance, elastic modulus, chemical resistance and small curing shrinkage are most often used.

Various methods such as prepredder method, hand lay-up method, filament winding method, pultrusion method, RTM method (resin transfer molding method) are applied to the production of fiber-reinforced composite materials.

Of these, the RTM method is a method in which a preform made of reinforcing fibers is placed in a mold, a resin is injected into the mold to impregnate the preform, and then the resin is cured to obtain a molded product. There is a great advantage that large members having various shapes can be molded in a short time.

Resins for the RTM method must have low viscosity to facilitate impregnation into preforms. It is necessary. If the viscosity of the resin is high, it takes a long time to inject, and the productivity may be low, or an unimpregnated portion may be formed in the obtained fiber-reinforced composite material. In the RTM method, a method of lowering the viscosity of the resin by raising the temperature of the resin can also be adopted.However, in this case, it is necessary to heat the entire mold, especially when molding a large member, which requires equipment and equipment. There is a significant disadvantage in terms of energy requirements. In addition, the curing reaction may progress due to heat during the injection, and the viscosity of the resin may increase. Therefore, a resin that does not require heating and has a sufficiently low viscosity near room temperature is strongly desired.

Epoxy resin is frequently used as the thermosetting resin used in the RTM method. In addition, in the RTM method, an unsaturated polyester resin, a burester resin, a fuanol resin, or the like is used as a thermosetting resin. Many of these unsaturated polyester resins, butyl ester resins, and fuñol resins have low viscosity at around room temperature, and have excellent workability of resin injection at around room temperature, but the resulting fiber-reinforced composite material has heat resistance and mechanical properties. It is desirable to use an epoxy resin from the viewpoints of achieving excellent heat resistance and reducing polymerization shrinkage during the curing reaction.

However, the epoxy resin obtained is a fiber-reinforced composite material that is excellent in heat resistance and mechanical properties but has high viscosity, so that the resin injection workability at room temperature is poor, or the viscosity at room temperature is low. Low heat resistance and excellent pouring workability, but the resulting fiber reinforced composite material lacks heat resistance or mechanical properties or only one of them, and molded products require excellent heat resistance and mechanical properties In applications, the epoxy resin had to be heated and used for the RTM method. Japanese Patent Application Laid-Open No. Hei 6-32 9763 discloses an epoxy resin composition in which epoxy resin is blended with getyl toluenediamine as a curing agent. There is still a problem that the viscosity of the resin is still high, and at around room temperature, the workability of injecting the resin is inferior, and the obtained fiber-reinforced composite material has a non-impregnated portion of the resin, thereby failing to obtain required mechanical properties. DISCLOSURE OF THE INVENTION In order to solve such a problem, an epoxy resin composition of the present invention has the following constitution. That is, an aromatic epoxy resin having two or more functional groups, an aromatic amine compound, and Is an epoxy resin composition containing an alicyclic amine compound, which comprises at 25 ° C. a main agent composed of the epoxy resin and the aromatic amine compound and / or the alicyclic amine compound. ⁵ minutes after mixing with the curing agent, the viscosity at 25 ° C is 1 to: L 500 mPa · s, and T c, tc satisfying the following formula (1) An epoxy resin composition characterized in that Tg is present.

T g≥T c + 20-k X (T c-90) (1)

When 6 0 ≤ T c <90, k = 0,

When 90≤T c≤2 0 0, k = 0.35

T c: Maximum temperature in the curing process (° C) (60 ≤ T c ≤ 200)

t c: Maximum temperature holding time (min) (1 ≤ t c ≤ 1 2 0)

T g: Tc (° C), glass transition temperature of the epoxy resin composition after elapse of tc (minutes) Best mode for carrying out the present invention An epoxy resin composition in which an aromatic amine compound and / or an alicyclic amine compound is blended with an epoxy resin (hereinafter simply referred to as an epoxy resin composition) can provide an epoxy resin composition at a temperature near room temperature, that is, the present invention. In this case, the workability of resin injection at around 25 ° C and the impregnation into the reinforcing fibers have been greatly improved, and the resulting fiber-reinforced composite material has both excellent heat resistance and mechanical properties. It has been found that the present invention has been made.

The epoxy resin composition of the present invention comprises an aromatic epoxy resin having two or more functionalities. Here, “functional” in the bifunctional means an epoxy group. In the present invention, monomers or oligomers before undergoing a polymerization or curing reaction are also referred to as “epoxy resins”. In addition, an epoxy resin composition in which elements required for polymerization or curing reaction are mixed is referred to as an “epoxy resin composition”, and a polymerized or cured reaction is referred to as “epoxy resin cured product” (or “resin Cured product "or" cured product "or cured product of epoxy resin composition). In addition, aromatic epoxy resin means an epoxy resin having an aromatic ring in a molecule. this A bifunctional or higher aromatic epoxy resin reacts with a curing agent to form a crosslinked structure, and is compounded to give fiber-reinforced composite materials (hereinafter simply abbreviated as composite materials) excellent heat resistance and mechanical properties. Is what you do.

In order to enhance the impregnation property of the reinforcing fibers, it is necessary that the viscosity of the epoxy resin composition around room temperature is sufficiently low. However, if the viscosity is too low, the resulting composite material may cause voids in the unimpregnated part. The main agent and the curing agent have a viscosity at 25 ° C of 1 to 300 m, respectively, from the viewpoint of improving the injection workability, the impregnation property, and the mixing property between the main agent and the curing agent. It is good to be in the range of Pa · s, preferably:! 2200 mPa as, more preferably l l100 mPa · s.

In the present invention, when the viscosity of the main agent at 25 ° C. is in the range of 2000 to 300 mPas, the viscosity of the curing agent at 25 ° C. is 1 to 500 m It is preferably in the range of Pa · s. When the viscosity of the main agent at 25 ° C. is in the range of 100 to 200 mPa · s, the viscosity of the curing agent at 25 ° C. is 1 to: 100 ° m It is preferably in the range of P a · s. Furthermore, when the viscosity of the main agent at 25 C is in the range of 1 to 100 mPas, the viscosity of the curing agent at 25 ° C is in the range of 1 to 3 OOOmPas. Preferably it is.

In curing the epoxy resin composition obtained after mixing the main agent and the curing agent, various methods are selected depending on the application. Specifically, a method of raising the temperature at a constant speed, reaching the maximum temperature Tc (° C), keeping the temperature constant for tc (minutes), and then lowering the temperature is one example. In addition, after the temperature rises at a constant speed and reaches a certain temperature, the temperature is kept constant for a certain time, then the temperature is started again, and the maximum temperature T c

After the temperature reaches (° C), the temperature is kept constant for t c (minutes), and then the temperature is lowered, so-called step cure method.

In order to achieve good heat resistance of the obtained composite material, the maximum temperature Tc is in the range of 60 to 200 ° C. in the process of curing the epoxy resin composition. In addition, from the viewpoint of increasing productivity, the time tc for keeping the maximum temperature constant is in the range of 1 to 120 minutes.

In addition, the epoxy resin composition at the time when tc (minute) has elapsed at Tc (° C) The glass transition temperature Tg of the cured product of the epoxy resin composition is measured from the temperature of Tc (° C.) to room temperature and then measured by the method described in Examples.

The heat resistance of the composite material is affected by the glass transition temperature Tg of the cured product of the epoxy resin composition, which is a matrix resin.The glass transition temperature Tg is generally determined by the maximum temperature Tc (° C ) And the time to keep the maximum temperature constant tc (minutes).

In the present invention, when the maximum temperature Tc is in a low temperature range of 60 ° C or more and less than 90 ° C, the glass transition temperature Tg of the resin composition as the matrix resin is higher than the maximum temperature Tc. It must be higher than 20 ° C. That is, it is necessary that T c, t c, and T g satisfy the following equation (1).

T g ≥ T c + 20 (1) Also, when the maximum temperature T c is in the high temperature range of 90 ° C or more and 200 ° C or less, T c that satisfies the following equation (1 '): tc and Tg need to be present.

T g ≥ T c + 20-0.35 X (T c-90) (1 ') In the present invention, the maximum temperature T c (° C which satisfies the above expression (1) or (1') ) And its holding time tc (min) are adopted as manufacturing conditions, and the maximum temperature Tc (° C) is kept constant for the time tc (min) to produce a composite material.

Since the elastic modulus of the cured resin obtained by curing the epoxy resin composition affects the mechanical properties of the composite material, particularly the compressive strength, in the present invention, the resin curing measured by the method described below is used. The tensile modulus E of the material plate is preferably in the range of 3.2 to 5 GPa, and more preferably in the range of 3.4 to 4.8 GPa. If it is less than 3.2 GPa, the compressive strength of the composite material may be insufficient, and if it exceeds 5 GPa, the toughness of the composite material may be insufficient.

In the present invention, it is preferable to mix the main agent and a curing agent to be described later to form an epoxy resin composition before use, and then inject the composition to produce a molded article such as a composite material. is there.

The epoxy resin composition of the present invention is obtained by mixing the main agent and the curing agent, and then viscosity of the epoxy resin composition at 25 ° C after 5 minutes at 25 ° C (hereinafter abbreviated as ₅ ). , Must be in the range of 1-1500 mPas, preferably 1 1100 mPa as, more preferably 100 7700 mPa · s.

Further, the epoxy resin composition according to the present invention is obtained by mixing the main agent and the curing agent, and then mixing the epoxy resin composition at 25 ° C. at 25 ° C. at 25 ° C. in a temperature environment of 25 ° C. Viscosity in s units (hereinafter abbreviated as r? ₆ ) Force It is preferable to satisfy the following expression (2).

1 ≤ 77 ₆ . ≤ 1 5 0 0 (2)

More preferably, the viscosity of the epoxy resin composition at 25 ° C. (hereinafter, abbreviated as ₁₂ ) at 125 ° C. in a temperature environment of 25 ° C. is 1 to 150 mP. a 'in the range of _S, particularly preferably under 2 5 ° C temperature environment, the viscosity of the epoxy resin composition of 2 5 ° C at the time of elapse 2 4 0 minutes (hereinafter, eta _24. hereinafter), 1 11500 mPa · s.

Alternatively, the viscosity of the epoxy resin composition at 25 ° C. at the time when 240 minutes have passed in a temperature environment of 25 ° C. ₂₄ . Is preferably in the range of l to 100 mPa · s, and more preferably in the range of 100 to 700 mPa · s.

And, the epoxy resin composition according to the present invention comprises: What? 77 ₆ divided by 7. [7] preferably satisfies the following expression (3), and more preferably ₁₂ . Divide by ₅ or ₁₂ 7) ₅ is in the range of 1 to 3, and particularly preferably 7) ₂₄ . Divided by η ₅ r; ₂₄ . / η ₅ is in the range of 1-3. If the ratio is out of this range, the workability of injecting the resin and the impregnation into the reinforcing fibers may be reduced. The bifunctional or higher aromatic epoxy resin used in the present invention is an epoxy resin having an aromatic ring and having two or more epoxy groups in one molecule. Examples of the aromatic epoxy resin having two epoxy groups include the following. First, bisphenol ノール type epoxy resin obtained from bisphenol 、, bisphenol F type epoxy resin obtained from bisphenol F, bisphenol S type epoxy resin obtained from bisphenol S, and tetrabromobisphenol A Bisphenol type epoxy resin such as tetrabromobisphenol A type epoxy resin. Commercially available bisphenol A type epoxy resin For example, Epicoat 825 (epoxy equivalent of 172-17-178), Epikoto 828 (epoxy equivalent of 184-19-194), Epikop 833 (epoxy equivalent of 230) 2 Epoxy Coat 1001 (Epoxy Equivalent 450-500), Epikote 100 (Epoxy Equivalent 600-700), Epicot 100 3 (Epoxy Equivalent) 670-770), Epikoto 1004 (epoxy equivalent 875-975), Epikoto 100 (epoxy equivalent 175-222), epikote 1 0 9 (epoxy equivalent 2400 to 3300), epicoat 1100 (epoxy equivalent 30000 to 500) (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd.) ), Epototo YD-1 28 (Epoxy equivalent 184-194) Epototo YD-0 1 1 (Epoxy equivalent 450-500), Epotote YD-0 14 (Epoxy equivalent 90 0 to 100), report YD—0 17 (epoxy equivalent 1 750) Epoteto YD-019 (epoxy equivalent 240 000 to 300 000), epoteto YD-222 (epoxy equivalent 400 000 to 600 000), (Registered trademark, manufactured by Toto Kasei Co., Ltd.), Epiclone 840 (epoxy equivalent 180-190), Epiclone 850 (epoxy equivalent 184-194), Epiclone 1 050 (Epoxy equivalent 450-500), Epiclone 305 (Epoxy equivalent 7440-860), Epiclone HM-101 (Epoxy equivalent 320-390) 0) (Registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.), Sumiepoxy ELA-128 (registered trademark, epoxy equivalent: 184-194, manufactured by Sumitomo Chemical Co., Ltd.), DER 33 1 (registered trademark, epoxy equivalent: 182-192, manufactured by Dow Chemical Co., Ltd.). Commercially available bisphenol F-type epoxy resins include Epicote 806 (epoxy equivalent of 160 to 170), Epikote 807 (epoxy equivalent of 160 to 175), and Epicoat E4 0 2 P (epoxy equivalent 6 10), epicoat E 4 0 3 P (epoxy equivalent 8 0 0), epi coat E 4 0 4 P (epoxy equivalent 9 3 0), epicoat E 4 0 0 7 P (epoxy equivalent 2 060), epicoat E 4 0 9 P (epoxy equivalent 3 0 3 0), epicoat E 4 0 10 P (epoxy equivalent 44.0) ( Epiclon 8330 (registered trademark, epoxy equivalent 170-190, manufactured by Dainippon Ink and Chemicals, Inc.), Epototo YD F-20 0 1 (Epoxy equivalent of 450 to 500), report YD F—200 4 (Epoxy equivalent of 900 to 100) 0) (Registered trademark, manufactured by Toto Kasei Co., Ltd.). Commercial products of bisphenol S-type epoxy resin include Denacol EX-251 (registered trademark, manufactured by Nagase Kasei Kogyo, epoxy equivalent: 189). Is a commercial product of Te trub Romo bisphenol A type epoxy resin, Epiko preparative 5 0 5 0 (registered trademark, produced by Yuka Shell Epoxy Ltd., epoxy equivalent 3 8 ^0-4 1 0), Epikuro down 1 5 2 ( Epoxy equivalent of 340 to 380, manufactured by Dainippon Ink and Chemicals, SMIE POXY ESB—400 T (manufactured by Sumitomo Chemical, epoxy equivalent of 380 to 420), potato YBD—36 0 (manufactured by Toto Kasei, epoxy equivalent: 350 to 370).

In addition, resorcin diglycidyl ether Denacol EX-201 (registered trademark, manufactured by Nagase Kasei Kogyo Co., Ltd., epoxy equivalent 118), hydroquinone diglycidyl ether Denacol EX-203 (registered trademark, Epoxy equivalent 1-12), manufactured by Nagase Kasei Kogyo Co., Ltd., Epiclone HP—4032H, a diglycidyl ether of 1,6-dihydroxynaphthalene (registered trademark, manufactured by Dainippon Ink and Chemicals, epoxy equivalent 2) 50), 9,9-bis (4-hydroxyphenyl) fluorene diglycidyl ether Ebon HPT Resin 107 (registered trademark, manufactured by Shell Co., epoxy equivalent 250-260), etc. Can be mentioned.

Further, diglycidyl dilinyl GAN (registered trademark, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 115 to 135), glycidyl ester phthalic acid diglycidyl ester, terephthalic acid diglycidyl ester And the like. In the present invention, it is conceivable to increase the crosslink density of the matrix resin as one method for imparting better heat resistance and mechanical properties to the composite material. For this purpose, it is preferable to blend a trifunctional or higher functional aromatic epoxy resin. The amount of trifunctional or more aromatic epoxy resins in the total epoxy resin, good Mashiku 5 0-1 0 0 wt% (more preferably 6 0-1 0 0 wt. / _0, rather more preferably 7 0: 1 0 0 weight ^_0/0).

In the present invention, a trifunctional aromatic epoxy resin represented by the chemical structural formula (I) is preferably compounded.

(In the formula, is a hydrogen atom or an alkyl group having about 1 to 4 carbon atoms.) As a commercially available product of such an epoxy resin, Epikote 6300 (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., N, N —Diglycidyl-p-glycidyloxydiline, viscosity in a temperature environment of 25 ° C .: 600 to 700 mPa · s), Araldite MY0510 (registered trademark, Ciba) N, N-Diglycidylol p-Glycidyloxylinyl, viscosity at 25 ° C temperature: 550-850 mPas, Sumiepoxy E LM 100 (registered trademark, Sumitomo) N, N-Diglycidyl-41-glycidyloxy-2-methylaniline, manufactured by Chemical Industry Co., Ltd., viscosity at 50 ° C temperature environment: 100 to 170 mPas), Sumiepoxy E LM 120 (registered trademark, manufactured by Sumitomo Chemical Co., Ltd., N, N-diglycidyl-m-glycidyloxyline), 50. C temperature The viscosity under boundary: 1 5 0 0~3 0 0 0 mP a · s) or the like can be used. Above all, Epicote 630 and Araldite MY0510 are preferably used because of their low viscosity.

The epoxy resin represented by the chemical structural formula (I) may be used alone or in combination of two or more.

Further, in the present invention, a tetrafunctional aromatic epoxy resin represented by the chemical structural formula (Π) can be blended.

(In the formula, R ₂ is a hydrogen atom or an alkyl group having about 1 to 4 carbon atoms.) Commercially available epoxy resins include TE TRAD-X (registered trademark, manufactured by Mitsubishi Gas Chemical Company, Inc.) , N, N ', Ν'-tetraglycidyl-m-xylylenediamine, viscosity at 25 ° C temperature environment: 160 to 250 mPas can be used. . The epoxy resin represented by the chemical formula (II) may be used alone or may be mixed with the epoxy resin represented by the chemical formula (I).

The viscosity at 25 ° C. of the trifunctional or higher-functional aromatic epoxy resin is preferably in the range of 1 to 300 mPas, more preferably 1 to 200 mPas, Especially preferably, it is in the range of 1 to LOO OmPa's. If the viscosity exceeds 300 mPa · s, the viscosity of the epoxy resin composition increases, and the impregnating property of the reinforcing fibers is reduced.

The upper limit of the functional number of the aromatic epoxy resin is not particularly limited, but the matrix resin in the composite material becomes brittle because the cross-linking density is too high. Lack of toughness can be undesirable. In consideration of these, the weight average value of the functional number of the aromatic epoxy resin is preferably 2 to 6 (more preferably 2 to 5, and further preferably 2 to 4).

Further, in the present invention, as another method for obtaining more excellent heat resistance and mechanical properties by using a composite material, it is conceivable to connect the cross-linking points of the matrix resin with a rigid skeleton. However, when an epoxy resin having a rigid skeleton is blended, the viscosity of the epoxy resin composition may increase due to a low degree of internal freedom of molecules. this In order to solve such a problem, a low molecular weight (preferably 100 to 500) epoxy resin is used. Examples of the low molecular weight epoxy resin having a rigid skeleton include biphenyl type epoxy resins.

As a commercially available product of such an epoxy resin, Epicort YX400 (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., 4,4, dihydroxy 3,3 ', 5,5'-tetramethylbiphenyldiglycidyl ether) , Epikoto YX400H (registered trademark, manufactured by Yuka Shell Epoxy Co., 4,4'-dihydroxy 3,3 ', 5,5, -tetramethylbiphenyldiglycidyl ether), Epikoto YL6 1 2 1 L

(Registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyldiglycidyl ether) or the like can be used.

In the present invention, in order to optimize the viscosity of the epoxy resin composition, a low-viscosity epoxy resin may be blended in addition to the bifunctional or higher aromatic epoxy resin. As such a low-viscosity epoxy resin, a bi- or higher-functional daricidyl ether type aliphatic epoxy resin can be used.

In the present invention, the bifunctional or higher functional glycidyl ether type aliphatic epoxy resin preferably satisfies the following formula (4) in order to enhance mechanical properties such as heat resistance and compressive strength of the composite material. It is more preferable to satisfy (4 ′).

0≤ α≤ 4 (4)

0≤α≤3 (4 ') Here, the bicyclic or higher functional dalicidyl ether-type aliphatic epoxy resin forms a ring in the molecular chain that connects any two of the dalicidyloxy groups in the molecule. Indicates the number of atoms in the molecular chain where the number of atoms that do not belong is the largest.

α is an index of the flexibility of the molecular chain. As α increases, the molecular chains become more flexible, and the network structure of the matrix resin in the composite material becomes more flexible, resulting in a lack of mechanical properties such as heat resistance and compressive strength of the composite material. There is. The method for obtaining the molecular weight from the molecular structure of the epoxy resin will be described in detail below. The α is determined using, as an example, a bifunctional or higher-functional dalicydyl ether-type aliphatic epoxy resin represented by the following chemical structural formula.

There are two types of molecular chains connecting the two dalicidyl groups, as shown below.

1-2-3-4-5-6

1-2-7-8-5-6

The number of atoms that do not belong to the ring is 2 in each case. Therefore, α is 2. Further, _α is determined using a glycidyl ether type aliphatic epoxy resin having two or more functional groups represented by the following chemical structural formula as an example.

There are three types of molecular chains connecting the three dalicidyl groups as shown below.

1-2

twenty three

one two Three

In the first and second cases, the number of atoms that do not belong to the ring is two, and in the third case, the number of atoms that do not belong to the ring is three. Therefore, α is 3.

As a commercially available product of such a bifunctional or higher-functional daricidyl ether type aliphatic epoxy resin, the following products can be used.

Denacol EX810 (registered trademark, manufactured by Nagase Kasei Kogyo Co., Ltd., viscosity at 25 ° C temperature environment: 15 mPa * s, α = 2, the following chemical structural formula),

Roxy 67 (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., viscosity in a temperature environment of 25 ° C. 3 to 18 mPa * s, α = 4, the following chemical structural formula),

Denacol EX 911 (registered trademark, manufactured by Nagase Kasei Kogyo Co., Ltd., viscosity at 25 ° C temperature environment: 20 mPa · s, α = 2, the following chemical structural formula),

CH Α ₂ — CH-CH ₂ — 0— CH woo 0 ΓH— ³ 0— CH ₂ — CH Λ— CH ₂ hexoxy 6 8 (registered trademark, manufactured by Yuka-sur-Epoxy Co., Ltd., at a temperature of 25 ° C) Viscosity 13 to: L 8 mPa's, α = 3, the following chemical structural formula),

Evolite 80 MF (registered trademark, manufactured by Kyoeisha Chemical Co., Ltd., viscosity at 25 ° C. temperature environment: 120 to 180 mPa · s, α = 3, the following formula ),

Heroxy 107 (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., 25. Viscosity under C temperature environment: 55 to 75 mPas, α = 2, the following chemical structural formula),

Denacol EX313 (registered trademark, manufactured by Nagase Kasei Kogyo Co., Ltd., viscosity at 25 ° C temperature environment: 150 mPa's, α = 3, the following chemical structural formula),

Heroxy 4 4 (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., viscosity at 25 ° C. temperature environment: 200 to 330 mPa · s, α = 3, the following chemical structural formula),

Roxy 48 (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., viscosity at 25 ° C. temperature environment: 25 to 250 mPa · s, α = 3, the following chemical structural formula),

Y L6753 (model number, manufactured by Yuka Shell Epoxy Co., Ltd., viscosity in a temperature environment of 25 ° C .: 400 mPa · s, α = 1, the following chemical structural formula) can be used.

These bifunctional or higher-functional daricidyl ether type aliphatic epoxy resins may be used alone or in combination of two or more.

The compounding amount of the bifunctional or higher-functional daricidyl ether-type aliphatic epoxy resin (when a plurality of types are used, the total thereof) is preferably 1 to 50% by weight based on 100% by weight of the total epoxy resin. (More preferably 1 to 30 and still more preferably 1 to 10). If it exceeds 50% by weight, mechanical properties such as heat resistance and compressive strength of the composite material may be insufficient.

The bifunctional or higher glycidyl ether type aliphatic epoxy resin is generally described above. It has a low viscosity as compared with such an aromatic epoxy resin. The bifunctional or higher-functional daricidyl ether type aliphatic epoxy resin has a viscosity in a temperature environment of 25 ° C. of preferably 1 to 500 mPas, and preferably 1 to 300 mP. a · s, more preferably in the range of l to 100 mPas · s. If the viscosity exceeds 500 mPa · s, the viscosity of the epoxy resin composition may increase, and the impregnating property of the reinforcing fibers may decrease. The upper limit of the functional number of the bifunctional or higher-functional daricidyl ether-type aliphatic epoxy resin is not particularly limited, but the matrix resin in the composite material has an excessively high crosslinking density. It may become brittle, resulting in a lack of toughness in the composite material, which may be undesirable. In consideration of these, the weight average value of the functional number of the glycidyl ether type aliphatic epoxy resin is preferably 2 to 6 (more preferably 2 to 5, and further preferably 2 to 4).

The epoxy resin composition of the present invention comprises an aromatic amine compound and / or an alicyclic amine compound. These amine compounds are curing agents, and react by mixing with an epoxy resin as described above to give a cured product.

Here, the aromatic amine compound is a primary, secondary or tertiary amine having an aromatic ring, preferably a primary diamine having 6 to 25 (more preferably 6 to 17) carbon atoms. It is a family. The alicyclic amide compound is a primary, secondary or tertiary amide having an alicyclic ring, preferably having 6 to 25 (more preferably 6 to 15) carbon atoms. Primary diamine.

When the aromatic amine compound is blended, the aromatic amine compound preferably has a viscosity in a temperature environment of 25 ° C. in the range of 1 to 300 mPas, more preferably. Ha :! 2200 mPa · s, particularly preferably l l100 mPa · s. If the viscosity exceeds 300 mPa · s, the viscosity of the epoxy resin composition becomes high, and the impregnation into the reinforcing fibers may be reduced.

Commercially available aromatic amine compounds include Epicure W (registered trademark, manufactured by Yuka Shell Epoxy Co., Ltd., 2,4_Jetyl-6-Methyl-1m-phenylenediamine and 4,6-Jetyl-2-methyl-m —Mixed with phenylenediamine, viscosity at 25 ° C. temperature environment: 100 to 400 mPa · s), Kyahard A_A (registered trademark, Nippon Kayaku Co., Ltd.), 2, 2'-one-ethyl-4,4'-methylene dianiline, 25 ° C temperature Viscosity under ambient environment: 2000 to 300 mPa · s), Kyahard A-B (registered trademark, manufactured by Nippon Kayaku Co., Ltd.) Use a mixture of methylene dianiline and 4,4'-methylene dianiline, viscosity in a temperature environment of 25 ° C: 150 to 250 mPas Can be.

When an alicyclic amine compound is blended, the alicyclic amide compound preferably has a viscosity in a temperature environment of 25 ° C. in the range of 1 to 500 mPas, and is preferably used. Is preferably in the range of 1 to 300 mPa · s. When the viscosity exceeds 500 mPa · s, the viscosity of the epoxy resin composition increases, and the impregnating property to the reinforcing fibers may decrease. Further, the alicyclic amine compound preferably satisfies the following formula (5), and preferably satisfies the following formula (5 '), in order to enhance the mechanical properties such as heat resistance and compressive strength of the composite material. Is more preferred.

0 ≤ β ≤ 4 (5)

0 ≤ β ≤ 3 (5 ')

Here,; 3 is the number of atoms not belonging to a ring in the molecular chain formed by connecting any two of the amino groups in the molecule of the alicyclic amine compound, and Represents a number.

i3 is an index of the flexibility of the molecular chain. The larger the molecular weight, the greater the flexibility of the molecular chains and, consequently, the more flexible the network structure of the matrix resin in the composite material, which tends to result in a lack of mechanical properties such as heat resistance and compressive strength of the composite material. is there.

In the case where a plurality of alicyclic amide compounds having different | 3 values are present, the total / 3 value is calculated by the molar average.

Further, in the alicyclic amine compound, in order to avoid an excessive increase in the viscosity of the epoxy resin composition, an amino group in the molecule of the alicyclic amine compound is bonded to a secondary carbon or a tertiary carbon. Is preferred. This is based on the fact that amines bonded to primary carbon usually react faster with epoxy groups than amines bonded to secondary or tertiary carbon. In order for this effect to be fully exhibited, the number of amino groups bonded to the secondary or tertiary carbon is preferably at least 50% of the number of amino groups of the total alicyclic amine compound, more preferably Is more than 70%, more preferable Or 90% or more.

Furthermore, in order to improve mechanical properties such as heat resistance and compressive strength of the composite material, all amino groups contained in the molecule of the alicyclic amine compound are bonded to carbon constituting the ring structure. Is preferred.

Commercially available alicyclic amine compounds include Amicure P ACM (registered trademark, Air — '4,4', methylenebiscyclohexylamine, viscosity at 25 ° C temperature environment: 80 m. Pas, i3 = 1), Ankamin 204 (registered trademark, Air Products), 2,2'-dimethyl-4,4'-methylenebiscyclohexylamine, at a temperature of 25 ° C Viscosity: 120 mPa a's, / 3 = 1), DCH-99 (part number, manufactured by Dupont, 1,2-cyclohexanediamine, 21 ° C temperature Viscosity under environment: 7 mP a · s, β = 0) , 1, 8- Mensenjiamin (sigma one Aldori Tutsi Inc., 2 5 ° C temperature environment of _{viscosity: 8 0 m P a 'S} , i3 = l), iso Horonjiamin (Huls Viscosity at 25 ° C temperature environment: 13 mPa · s, β = 1), 1,3-bisaminomethylcyclohexane (Mitsubishi Gas Chemical Co., Ltd. ), Viscosity at 25 ° C temperature environment: 9 mPa's,] 3 = 2), 2,5 (6) -bisaminomethyl norbornane (Mitsui Chemicals, 25 ° C temperature environment) Lower viscosity: 16 mPa · s, / 3 = 2) etc. can be used.

In the present invention, an amine compound other than the aromatic amine compound and the alicyclic amine compound may be blended as a curing agent.

In the present invention, the active hydrogen of the amine compound contained in the epoxy resin composition (active hydrogen is a highly reactive hydrogen atom that is bonded to nitrogen, oxygen, sulfur, etc. in an organic compound, and has a large cross-linking effect. Preferably plays a role of 4 to 24. More preferably, it is 4 to 16, more preferably 4 to 8. If the value falls below the lower limit of the above numerical range, the crosslink density of the matrix resin in the composite material decreases, so that the heat resistance and the elastic modulus decrease, and further, the heat resistance, compressive strength, etc. of the composite material Tends to decrease mechanical properties. Above the upper limit, the matrix resin in the composite material becomes brittle because the crosslink density is too high, and as a result, the toughness of the composite material tends to be insufficient. When multiple types of amine compounds are mixed, the active hydrogen number is calculated by weight average. Put out. Alternatively, the amine compound having an active hydrogen number of 4 or more preferably accounts for 50 to 100% of all amine compounds.

Further, although different depending on the case, it is preferable that the content of the aromatic amine compound and the Z or alicyclic amine compound in the total amine compound is 50 to 100% by weight.

It is preferable that the main agent and the agent are mixed at a mixing ratio determined so as to satisfy the following formula (6).

0.5 ≤ R / R e≤ 2 (6)

Here, R represents the weight ratio of the curing agent to the main agent, and Re represents the ratio of the number of moles of epoxy groups per g of the main agent to the number of moles of active hydrogen per g of the curing agent.

Further, in the present invention, an appropriate curing accelerator can be blended for the purpose of lowering the maximum temperature Tc (° C) and shortening the maximum temperature holding time tc (minute). Known curing accelerators can be used. Specifically, sulfonic acid esters as disclosed in U.S. Pat. No. 5,888,877, and sulfonium salts as disclosed in U.S. Pat. No. 4,554,432 are preferably used. Further, in the present invention, a coloring agent, a surfactant, a flame retardant, and the like can be appropriately blended according to various purposes. However, it is preferable that the ratio of the epoxy resin (including the curing agent) occupied in the resin matrix (excluding reinforcing fibers, granular, and short-fiber filters) is 80% by weight or more.

The epoxy resin composition according to the present invention is suitably used for producing a composite material using the RTM method. A review of recent RTM methods in general (SAMPE Journal, Vol. 34, No. 6, pp. 7-19) states that the VARTM (Vacuum-Assisted RTM) method, VIMP (Variable Infusion Molding Process), TERTM (Thermal-Expansion RTM), RARTM (Rubber-Assisted RTM), RIRM (Resin Injection Recirculation Molding), CRTM (Continuous RTM), CI RTM (Co-Injection Resin) Transfer Molding), RLI (Resin Liquid Infusion), SCR IMP (Seeman's Composite Resin Infusion Molding Process), etc. are introduced. It can also be suitably used for a molding method similar to the method.

Preforms used in the RTM method include carbon fiber, glass fiber, and aramide fiber. Any reinforcing fibers processed into mats, wovens, knits, braids, unidirectional sheets, etc. are used. Particularly, in order to obtain a lightweight and high-strength member, carbon fiber is preferably used. The fiber weight% of the reinforcing fibers is preferably from 30 to 85.

Further, the epoxy resin composition according to the present invention can be suitably used for a method of impregnating a reinforcing fiber with a liquid epoxy resin at around room temperature, specifically, a handle, up method, a filament binding method, a pultrusion method and the like. it can. Examples Hereinafter, the present invention will be described in more detail with reference to Examples. In Examples and Comparative Examples, preparation of various samples and measurement of physical properties were performed under the following conditions. The results of these examples and comparative examples are summarized in Tables 1 to 5.

A. Viscosity

According to the method of measuring the viscosity using a conical one-plate rotary viscometer in JIS Z8883, the measurement was performed for each of the main agent and the curing agent under a temperature environment of 25 ° C.

Also, 100 g of the epoxy resin composition obtained by mixing the main agent and the curing agent (by confirming that they are uniformly dispersed by visual observation, stirring with a spatula until a while has passed, and for a total of about 3 minutes). , a circular bottom having a radius 2 5 mm, an inner diameter of 5 0 mm, placed in a polyethylene-made force-up consisting of cylindrical portion of the height 7 5 mm, the viscosity at the time of after five minutes at ² 5 ° C ₅ And viscosity at 60 ° C. at 25 ° C. , 2 5 ° viscosity eta _{1 20} at the time of the lapse of one 2 0 min at C, 2 5 ° Viscosity 7 ₂₄ at the time of elapse 2 4 0 minutes in C. Was measured according to the method described above.

Here, if the viscosity is 1 to 100 mPa · s, use a E-type viscometer (ELD type) manufactured by Toki Sangyo Co., Ltd. In the case of mPas, an E-type viscometer (EHD type) manufactured by Toki Sangyo Co., Ltd. was used. The rotor of the E-type viscometer had an angle of 1 ° 34 ′ and a radius of 24 mm. '

B. Preparation of cured resin plate

The epoxy resin composition obtained by mixing the epoxy resin and the curing agent is poured into a mold having a plate-shaped cavity with a thickness of 2 mm, and cured using an oven under the prescribed curing conditions. Then, a resin cured product plate having a thickness of 2 mm was obtained.

C. Glass transition temperature T g

The glass transition temperature Tg of the cured resin sheet obtained by the above method B was measured by the DMA method in accordance with S ACMA S RM 18 R-94. Here, the measurement was performed at a heating rate of 50 111 in and a measurement frequency of 1 Hz using a dynamic analyzer RDAII type manufactured by Rheometrics. D. Tensile modulus E

The resin cured product plate obtained by the method B above is compact in accordance with JIS K 7 13

A No. 1 (1 2) test piece was prepared and measured with a Tensilon at a temperature of 23 ° C to obtain a stress-strain curve. Tensile stress σ when strain is 0.001. .. ₀₁ (GP a), the tensile stress σ when the strain is 0.03. . . ^{From 3} (GP a), the tensile elastic modulus E was determined by the following equation.

E (GP a) = (σ ... ₀₃ -σ ... ₀₁ ) / (0. 0 0 3-0. 0 0 1)

Ε. Preparation of composite materials

Composite materials were prepared by RTM method. The mold used was an upper mold and a lower mold having cavities of 200 mm in length, 200 mm in width, and 2.0 mm in height. The pre-form, vertical 1 9 0 mm, lateral 1 9 0 mm carbon fiber fabric (Toray Industries Co., Ltd., model number: C07 3 7 3, 1 9 3 g / m 2) and the fiber direction in the same direction A stack of 10 sheets was used.

First, set the preform in the mold cavity, connect a vacuum pump to the suction port (one location) on the side of the mold, and reduce the pressure inside the mold to 0.1 mmHg or less. After mixing with the curing agent, the resin composition, which had been defoamed by being left under reduced pressure for 30 minutes, was injected from the resin injection port at the center of the upper mold to impregnate the preform. When the resin flowed out of the suction port, the resin injection port and subsequently the suction port were closed, and heated in an oven to cure the resin composition to obtain a flat composite material.

F. 0. Compressive strength

The 0 ° compressive strength of the flat composite material obtained by the method E was measured according to the method A in JIS K7706.

(Example 1)

Epicoate 630 was used as the epoxy resin, and Epicure W was used as the curing agent. Each viscosity, viscosity after mixing, and. , V7. Was measured. Here, the mixing ratio (the ratio of the weight of the main agent and the weight of the curing agent, hereinafter abbreviated as mixing ratio R) was set to 0.464.

In addition, a resin cured product plate was prepared by the following procedure.

(1) 1.5. The temperature is raised to 180 ° C by the amount of C,

(2) After reaching 180 ° C, hold for 120 minutes,

(3) The temperature was lowered to 25 ° C at 2.5 ° C.

With respect to the obtained cured resin plate, the 'laser transition temperature T g and the tensile modulus E were measured.

(Example 2)

Using epoxy resin 630 as an epoxy resin and ancamine 209 as a curing agent, the respective viscosities and the viscosity of the resin composition after mixing 7), 7}, 71 77 are used. Was measured. Here, the mixing ratio R was 0.6 13.

(1) Heat up to 60 ° C in 1.5 ° CZ minutes,

(2) Hold at 60 ° C for 180 minutes,

(3) 1.5. Temperature to 180 ° C in the same minute,

(4) Hold at 180 ° C for 120 minutes,

(5) The temperature was lowered to 25 ° C in 2.5 ° C.

With respect to the obtained cured resin plate, the glass transition temperature T g and the tensile modulus E were measured.

(Example 3)

A mixture of 60 parts by weight of Epicoat 630 and 40 parts by weight of Epicoat 807 as an epoxy resin, and Epicure W as a curing agent, the respective viscosities and the viscosity of the resin composition after mixing are used. ₅ and ₆ . , 7? Was measured. Here, the mixing ratio R was 0.384.

Further, a resin cured product plate was prepared in the same procedure as in Example 1. The glass transition temperature T g and the tensile modulus E of the obtained cured resin plate were measured.

(Example 4) A mixture of 70 parts by weight of Epicote 630 and 30 parts by weight of Heroxy 107 as an epoxy resin and Epicure W as a curing agent were used, and their viscosities and viscosity of the resin composition after mixing were ₅ When, . , Τ) r ₂₄ . Was measured. Here, the mixing ratio R was 0.409.

Further, a cured resin plate was prepared in the same procedure as in Example 1. The glass transition temperature T _g and the tensile modulus E of the obtained cured resin plate were measured.

(Example 5)

A mixture of 90 parts by weight of Epoxy 630 and 10 parts by weight of Heroxy 68 as the epoxy resin, and Epicure W as a curing agent, the respective viscosities and the viscosity of the resin composition after mixing 7 to ₅ ₆ , 7)! ₂₀ , η ₂₄ . Was measured. Here, the mixing ratio R was 0.448.

(Example 6)

A mixture of 90 parts by weight of Epoxy 630 and 10 parts by weight of Heroxy 68 as an epoxy resin and Ancamine 2049 as a curing agent were used. Viscosity and 7. , 77. Was measured. Here, the mixing ratio R was 0.592.

Further, a resin cured product plate was prepared in the same procedure as in Example 2. The glass transition temperature T g and the tensile modulus E of the obtained cured resin plate were measured.

(Example 7)

A mixture of 90 parts by weight of epoxy 630 and 10 parts by weight of heroxy 68 as an epoxy resin, and ancamine 2049 as a curing agent, each having a viscosity and a viscosity of the resin composition after mixing. ₅ and. , Η _{1 20} , 77 ₂₄ . Was measured. Here, the mixing ratio R was 0.592.

(1) Heat up to 60 ° C in 1.5 ° CZ minutes,

(2) Hold at 60 ° C for 180 minutes,

(3) Heat up to 130 ° C in 1.5 ° CZ minutes, (4) Hold at 130 ° C for 120 minutes,

(5) The temperature was lowered to 25 ° C in 2.5 ° CZ minutes.

With respect to the obtained cured resin plate, the glass transition temperature T _g and the tensile modulus E were measured.

(Example 8)

A mixture of 70 parts by weight of Epicote 63 and 30 parts by weight of Epomic R710 as an epoxy resin, and an epoxy resin W as a curing agent. Viscosity? 7 ₅ ",, 77. Was measured. Here, the mixing ratio R was set to 0.4 0 2.

(Example 9)

A mixture of 70 parts by weight of epoxy 630 and 30 parts by weight of GAN as an epoxy resin and epicure W as a curing agent were used, and the respective viscosities and viscosities of the resin composition after mixing were 7? _5, 7? _6. , Η ₂₄ . Was measured. Here, the mixing ratio R was 0.433.

(Example 10)

A mixture of 70 parts by weight of Epicote 63 and 30 parts by weight of GAN as an epoxy resin, and ancamine 204 as a curing agent, each having a viscosity and a resin composition after mixing The viscosity of 77 ₅ and 7) ₆ . ,? 7 ri. Was measured. Here, the mixing ratio R was 0.572.

(Example 11)

A mixture of 70 parts by weight of Epicote 630 and 30 parts by weight of Denacol EX 721 as epoxy resin, using Epicure W as a curing agent, the respective viscosities, and the resin composition after mixing And the viscosity of the 77! 77. Was measured. here, The mixing ratio R was 0.412.

Further, a resin cured product plate was prepared in the same procedure as in Example 1. The glass transition temperature T _g and the tensile modulus E of the obtained cured resin plate were measured.

(Example 12)

A mixture of 90 parts by weight of Epoxy 828 and 10 parts by weight of Heroxy 68 as an epoxy resin, and isophorone diamine as a curing agent were used, and the respective viscosities and the viscosity of the resin composition after mixing were ₅ ,. , Ό. Was measured. Here, the mixing ratio R was 0.232.

Further, a resin cured product plate was prepared in the same procedure as in Example 7. The glass transition temperature T g and the tensile modulus E of the obtained cured resin plate were measured.

(Example 13)

A mixture of 30 parts by weight of Epikote 630 and 70 parts by weight of Epicoat 807 as an epoxy resin, a mixture of 50 parts by weight of isophorone diamine as a curing agent and 50 parts by weight of ancamine 2049 The viscosities used were the viscosities of the resin composition after mixing 75 and _{6, respectively} . , ₁₂ . , 77 ₂₄ . Was measured. Here, the mixing ratio R was 0.358.

(Example 14)

Using the same epoxy resin composition as in Example 5, a composite material was prepared in the following procedure. (1) 1.The temperature is raised to 60 ° C in 5 ° CZ minutes,

(2) Hold at 90 ° C for 600 minutes,

(3) Heat up to 180 ° C in 1.5 ° CZ minutes,

(4) Hold at 180 ° C for 120 minutes,

(5) The temperature was lowered to 25 ° C in 2.5 ° CZ minutes.

Observation of the surface and cross section of the obtained composite material with an optical microscope revealed no unimpregnated portions and voids, and the quality was good. Next, the 0 ° compression strength of this composite material was measured.

(Example 15) Using the same epoxy resin composition as in Example 6, a composite material was prepared in the following procedure.

(1) The temperature is raised to 60 ° C in 1.5 ° CZ minutes,

(2) Hold at 60 ° C for 180 minutes,

(3) The temperature is raised to 180 ° C in 1.5 ° CZ minutes,

(4) Hold at 180 ° C for 120 minutes,

(5) The temperature was lowered to 25 ° C in 2.5 ° CZ minutes.

(Comparative Example 1)

Epoxy resin 630 as an epoxy resin, Jeffamine D 230 as a curing agent (registered trademark, manufactured by Jefferson Chemical Co., Ltd., polyoxypropylenediamine, viscosity at 25 ° C temperature environment: 9) m Pa · s, β = 9.8) and the respective viscosities, the viscosity of the resin composition after mixing 7 ^, and η ₂₄ . Was measured. Here, the mixing ratio R was 0.621.

(Comparative Example 2)

As the epoxy resin, Epiko preparative 8 2 8, using Epikyua W as a curing agent, a viscosity 7? ₅ of the respective viscosity, the resin composition after mixing, 77, _24. Was measured. Here, the mixing ratio R was 0.283.

(Comparative Example 3)

Using epoxy resin 828 as the epoxy resin and Ancamine 209 as the curing agent, the respective viscosities and the viscosity of the resin composition after mixing are 7? 7. , 77 77 were measured. Here, the mixing ratio R was set to 0.374.

Further, a resin cured product plate was prepared in the same procedure as in Example 2. The glass transition temperature T g and the tensile modulus E of the obtained cured resin plate were measured. (Comparative Example 4)

Epoxy resin as epoxy resin, Jeffamine D23 as curing agent

Using 0, each viscosity, viscosity of the resin composition after mixing 7 ?, 7}, 77 77

₂₄₀ was measured. Here, the mixing ratio R was 0.379.

(Comparative Example 5)

As a epoxy resin, a mixture of 40 parts by weight of Epicote 630 and 60 parts by weight of Heroxy 107, and using Epicure W as a curing agent, the respective viscosities and the viscosity of the resin composition after mixing? 7 ₅ and T). Was measured. Here, the mixing ratio R was 0.354.

(Comparative Example 6)

As an epoxy resin, 70 parts by weight of Epikote 63 and YED216 (registered trademark, Yuka Shell Epoxy Co., Ltd., 1,6-hexanediol diglycidyl ether, viscosity at 25 ° C temperature environment) : 30 to 35 parts by weight of 15 to 35 mPa · s, α = 6), using Epicure W as a curing agent, the respective viscosities, and the viscosity of the resin composition after mixing 7? 7. , 77. Was measured. Here, the mixing ratio R was 0.412.

(Comparative Example 7)

Using the same epoxy resin composition as in Comparative Example 1, a composite material was prepared in the same procedure as in Example 15.

Observation of the surface and cross section of the obtained composite material with an optical microscope revealed no unimpregnated portions and voids, and the quality was good. Then, for this composite material, 0. The compression strength was measured.

(Comparative Example 8) Using the same epoxy resin composition as in Comparative Example 2, a composite material was prepared in the same procedure as in Example 14.

The obtained composite material had a portion not impregnated with the resin at the end, and the quality was poor.

Table Example 1 Example 2 Example 3 Example 4 Example 5 Epoxy resin composition

(Main agent)

Ebikoto 630 [3ArEnl 100 100 60 70 90 Epikoto 807 [2ArEp] 40

Heroxy 107 [2GIFaEp] 30

Heroxy 68 [2GIFaEp] 10

(Curing agent)

Epicure W [ArAm] 46.4 38.4 40.9 44.8 Ancamine 2049 [FaAm] 61.3 Viscosity of main agent (m Pa · s) 680 680 1180 278 362 Viscosity of curing agent (m Pa ■ s) 187 120 187 187 187 Mixing ratio R 0.464 0.613 0.384 0.409 0.448 η (ma s 670 270 980 344 474

m Pa ■ s 675 292 988 346 477 r / (m Pa a's) 678 332 995 351 480

7j (m Pa's) 690 420 1020 360 488 Curing conditions

Maximum temperature in the curing process τ <: (° c) 180 180 180 180 180 Maximum temperature holding time t c (min) 120 120 120 120 120

T c + 20— k (T c -90) (° C) 169 169 169 169 169 Resin cured properties

Glass transition point T g (° C) 227 230 203 192 210 Tensile modulus E (GP a) 3.6 3.6 3.3 3.5 3.5 Table 2 Example 6 Example 7 Example 8 Example 9 Example 10

Ε

Q.

Epoxy resin composition

(Main agent)

Vehicle 630 L3ArEpJ 90 90 70 70 70 Heroxy 68 [2GIFaEp] 10 10

Epomic R710 [2ArEp] onυ

G A N (ZArEpj 30 30

(Curing agent)

Epicure W [ArAm]

Ancamine 2049 [CyAm] 59.2 59.2 57.2 Viscosity of base agent (mP a ■ s) 362 362 1027 439 439 Viscosity of hardener (mP β-s) 120 120 187 187 120 Mixing ratio R 0.592 0.592 0.402 0.433 0.572

211 211 823 501 238 η (mPa's) 243 243 829 509 299. (m P a 's) 297 297 835 519 416 rj (m P a' s) 443 443 850 544 713 Curing conditions

Maximum temperature in curing process T c: (° C) 180 130 180 180 180 Maximum temperature holding time t c (min) 120 120 120 120 120

T c + 20- k (T c -90) (° C) 169 136 169 169 169 169

Glass transition point T g (° C) 222 171 211 205 211 Tensile modulus E (GP a) 3.7 3.2 3.4 3.9 4.0 Table 3 Example 11 Example 12 Example 13 Epoxy resin composition

(Main agent)

Epikoto 630 [3ArEp] 70 30 Denacol EX 721 [2ArEp] 30

Epikoto 828 CD [2ArEp] 90

Epitop 807 [2ArEp] 70 Heroxy 68 [2GIFaEp] 1 I π υ

(Curing agent)

Epicure W [ArAra] 41.2

Ancamine 2049 [CyArAm]

Isophorone diamine [GyAr Am] 23.2 17.9 Viscosity of base material (m P a ■ s) 685 3600 1990 Viscosity of hardener (m P a -s) 187 18 33 Mixing ratio R 0.412 0.232 0.358 (m P a ■ s) 698 1020 465

77 (mPas) 709 2610 749 (mPas) 720 17400 1540 rj (mPas) 750 Unmeasurable 33600 Curing conditions

Maximum temperature in curing process Tc (° C) 180 130 130 Maximum temperature holding time tc (min) 120 120 120

T c + 20- k X (T c -90) (° C) 1β9 136 136

Glass transition point T g (° C) 195 141 137 Tensile modulus E 3.9 3.3 3.4 Table 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Epoxy resin composition

(Base agent)

Epitop 630 [3ArEp] 100 40 70 Epitop 828 [2ArEp] 100 100 100

Heroxy 107 [2GIFaE _P ] 60

Υ Ε D216 [2GIFaEpJ 30

(Curing agent)

Epicure W [ArAm] 28.3 35.4 41.2 anchor ;; 2049 LCyAmJ 37. t

Jeffamine D 230 [FaAm] 62.1 37.9 Viscosity of base agent (mP a ■ s) 680 14600 14600 14600 138 52 Viscosity of hardener (mP a ■ s) 9 187 120 9 187 187 Mixing ratio R 0.621 0.283 0.374 0.379 0.354 0.412 r ) (m P a s s 73 5 100 3410 513 202 209 r? (m P a ■ s 84 5 120 5 240 1010 203 210

T) \ (m P aS) 99 5160 9620 1840 203 212 η (m P a 's) 139 5200 24200 4090 205 214 Curing conditions

Maximum temperature during curing process Tc (° C) 180 180 180 180 180 180 Maximum temperature holding time tc (min) 120 120 120 120 120 120, ⁰ r ^ ヽ

Glass transition point T g (° C) 151 197 203 129 128 167 Tensile modulus E (GP a) 3.0 3.1 3.0 2.8 3.1 3.1 Table 5

(Explanation of symbols in Table 5)

[3ArEp] Trifunctional aromatic epoxy resin

[2ArEp] Bifunctional aromatic epoxy resin

[2GeFaEp] Bifunctional glycidyl ether type aliphatic epoxy resin

[ArAm] Aromatic amine compounds

[CyAm] Alicyclic amine compounds

[FaAm] Aliphatic amine compounds

INDUSTRIAL APPLICABILITY The epoxy resin composition according to the present invention has a low viscosity near room temperature and has excellent impregnation into reinforcing fibers. Further, thereby, a composite material having excellent mechanical properties such as heat resistance and compressive strength can be produced.

Composite materials obtained from the epoxy resin composition according to the present invention include aircraft members, satellite members, automobile members, bicycle members, railway vehicle members, ship members, building members, flywheels, pressure vessels, windmill blades, oil risers, It can be suitably used for sports equipment. Particularly, it can be suitably used for aircraft members and artificial satellite members requiring heat resistance.

Claims

The scope of the claims

1. An epoxy resin composition comprising a bifunctional or more aromatic epoxy resin, an aromatic amine compound and / or an alicyclic amine compound, wherein at 25 ° C., a main agent comprising the epoxy resin and After mixing the aromatic amide compound and the curing agent containing the aromatic or alicyclic amide compound, the viscosity at 25 ° C. after 5 minutes at 25 ° C. Sl to 150 mPas Wherein T c, tc, and T g satisfy the following formula (1):

T g≥T c + 20-k X (T c-90) (1)

When 6 0 ≤ T c <90, k = 0,

When 9 0 ≤ T c ≤ 2 0 0, k = 0.35

T c: Maximum temperature in the curing process (° C) (60 ≤ T c ≤ 200)

t c: retention time of maximum temperature (min) (l ≤ t c ≤ 1 2 0)

T g: The glass transition temperature of the epoxy resin composition after the elapse of t c (minutes) at T c (° C)

2. The epoxy resin composition according to claim 1, wherein the aromatic epoxy resin is a trifunctional or higher epoxy resin.

3. The epoxy resin composition according to claim 2, wherein the amount of the trifunctional or higher functional aromatic epoxy resin is 50 to 100% by weight based on 100% by weight of the total epoxy resin.

4. The epoxy resin composition according to claim 2, wherein the viscosity of the trifunctional or higher-functional aromatic epoxy resin at 25 ° C. is in the range of 1 to 300 mPa · s.

5. The epoxy resin composition according to any one of claims 1 to 4, wherein the viscosity at 25 ° C after 5 minutes from the mixing is in the range of 1 to 100 mPas. .

6. The method according to any one of claims 1 to 5, wherein a tensile elastic modulus E at 23 ° C of the cured resin obtained by curing the epoxy resin composition is in a range of 3.2 to 5 GPa. A oxy resin composition.

7. The epoxy resin composition according to any one of claims 1 to 6, which satisfies the following formulas (2) and (3). 1 ≤ ₆ . ≤ 1 5 0 0 (2)

: Viscosity of epoxy resin composition at 25 ° C (m P a · s) at 25 ° C at 25 ° C after mixing the main agent and curing agent

7] ₆ . : After mixing the main agent and the curing agent, 2 minutes after 60 minutes in a 25 ° C temperature environment

Viscosity of epoxy resin composition at 5 ° C (m P a · s)

8. The epoxy resin composition according to any one of claims 1 to 6, which satisfies the following formulas (2,) and (3,).

1 ≤ ₄ . ≤ 1 0 0 0 (2 ')

1 ^ 3V3)

? 7 _5: After mixing the base and curing agent, 2 5 ° C temperature environment, the viscosity of the epoxy resin composition of 2 5 ° C at the time five minutes have passed (m P a · s)

Hi ₂₄ . : Viscosity of epoxy resin composition at 25 ° C at 240 ° C in a temperature environment of 25 ° C after mixing the main agent and the curing agent (mP a · s)

9. The epoxy resin composition according to any one of claims 1 to 8, further comprising a bifunctional or higher-functional daricidyl ether-type aliphatic epoxy resin.

10. The epoxy resin composition according to claim 9, wherein the bifunctional or higher functional glycidyl ether type aliphatic epoxy resin satisfies the following formula (4).

0 ≤ α ≤ 4 (4)

α: in a molecular chain in which the number of atoms that do not belong to a ring is the largest in a molecular chain formed by connecting any two glycidyloxy groups in a molecule of a bifunctional or higher glycidyl ether type aliphatic epoxy resin, Number of atoms

11. The method according to claim 9, wherein the blending amount of the bifunctional or higher-functional glycidyl ether type aliphatic epoxy resin is 1 to 50% by weight based on 100% by weight of the total epoxy resin. Epoxy resin composition. ―

1 2. A composition comprising an aromatic amine compound, wherein the viscosity of the aromatic amine compound at 25 ° C. is in the range of l to 30′0 mPas. 11. The epoxy resin composition according to any one of 1 to 11.

1 3. It comprises an alicyclic amine compound, and the alicyclic amine compound has a temperature of 25 ° C. The epoxy resin composition according to any one of claims 1 to 12, wherein the viscosity of the epoxy resin is in the range of 1 to 500 mPa · s.

14. The epoxy resin composition according to any one of claims 1 to 13, comprising an alicyclic amine compound, wherein the alicyclic amine compound satisfies the following formula (5).

0 ≤ β ≤ 4 (5) β: The molecular chain in which the number of atoms that do not belong to the ring is the largest among the molecular chains connecting any two amino groups in the alicyclic amine compound. Number of the atoms in

15. An alicyclic amine compound comprising an alicyclic amine compound, wherein the alicyclic amine compound has an amino group bonded to a secondary or tertiary carbon in the molecule. The epoxy resin composition according to any one of the above.

16. The epoxy resin composition according to claim 15, wherein the alicyclic amine compound is one in which all amino groups in the molecule are bonded to secondary or tertiary carbon.

17. An epoxy resin composition for a fiber-reinforced composite material, comprising the epoxy resin composition according to any one of claims 1 to 16.

18. A fiber-reinforced composite material comprising a cured product of the epoxy resin composition according to any one of claims 1 to 17 and reinforcing fibers.

19. The fiber-reinforced composite material according to claim 17, wherein the reinforcing fibers are carbon fibers.