JP2003040973A - Resin composition for composite material, intermediate material for composite material and composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin material for composite material, an intermediate material for composite material, and a composite material having excellent mechanical properties, which give the composite material an excellent yield strength against large deformation. SOLUTION: An isocyanate-modified epoxy resin 70 to 15 parts per 100 parts by weight of bisphenol A type epoxy resin and / or bisphenol F type epoxy resin is used.
0 parts by weight, 3 to 45 parts by weight of a copolyester resin, and 5 to 25 parts by weight of an epoxy resin curing agent, a phenol novolak type epoxy resin and / or a cresol novolak type resin composition in addition to these resin components A resin composition for a composite material containing 85 parts by weight or less of an epoxy resin and containing 50 to 150 parts by weight of an isocyanate-modified epoxy resin, and a composite containing 1 to 1000 ppm of an antifoaming agent based on the total amount of the composition in addition to these resin components Resin composition for materials.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for a composite material, an intermediate material for a composite material obtained by impregnating the composition with a reinforcing fiber, and a composite material obtained by molding the intermediate material for a composite material. Regarding

[0002]

2. Description of the Related Art Composite materials having carbon fiber, glass fiber or the like as a reinforcing material are used for sports / leisure products such as golf shafts, fishing rods and tennis rackets; aircraft related applications; printing ink rolls; Used for industrial materials such as pressure vessels and medical applications, bridge repairs, civil engineering repairs, etc. Furthermore, in recent years, such composite materials have been increasingly used in sports equipment, particularly golf shafts.

Composite materials such as reinforced fiber plastics (FRP) and carbon fiber reinforced plastics (CFRP) are made into prepreg by impregnating a matrix resin into a reinforced fiber base material such as carbon fiber, glass fiber, aramid fiber or boron fiber. It can be obtained by laminating these and curing at an appropriate temperature.

As a matrix resin for CFRP, an epoxy resin having excellent adhesiveness to carbon fibers is adopted. In recent years, golf shafts have been diversified, lightweight shafts and long shafts have been developed, and the thickness of the shaft has become thinner. Therefore, there is a concern that the shaft will be greatly deformed and damaged. The bisphenol A type epoxy resin that has been mainly used from the past has a low composite physical property, particularly low interlaminar shear strength (ILSS) and a small elongation of the resin, so that it is weak against deformation. Furthermore, the reinforced fiber is impregnated with the resin composition. The resulting prepreg has a problem of low drapeability.

On the other hand, the polyfunctional epoxy resin has a short inter-crosslinking distance, which raises the glass transition temperature, and therefore the heat resistance, the interlaminar shear strength (ILSS) and the bending strength of the obtained molding are increased. On the other hand, when a resin composition is produced, its reactivity is high, and thus there is a problem in the quality of the obtained resin composition and the safety at the time of compounding. Furthermore, when a polyfunctional epoxy resin is the main component, the cured resin becomes brittle, which makes it suitable for sports applications, especially the recent lightweight CFRP.
Not suitable for golf shafts.

[0006]

However, in order to impart high bending strength and high interlaminar shear strength to the composite material as described above, a phenol novolac type epoxy resin,
A composite material produced by using a matrix resin formed by mixing a polyfunctional epoxy resin such as a glycidylamine type epoxy resin with a bisphenol type epoxy resin has a problem that the resistance to large deformation and the impact resistance are significantly reduced. there were.

Further, as a means for improving the proof stress and the impact resistance against a large deformation, a thermoplastic resin such as polyether sulfone, nylon or the like or a rubber modified resin is added, and such a system is known. In this case, the viscosity of the resin increases, and the resin mixing process becomes very complicated. Further, acrylic resin fine particles and butadiene fine particles are known as toughness improvers, but when the resins are mixed, air is mixed and the like cannot be obtained as a satisfactory resin for the prepreg. Hollow pipes such as golf shafts are generally characterized by variously changing the laminated structure depending on the application. When pitch-based low elastic modulus and high elastic modulus carbon fibers are used as a part of the laminated structure, peeling may occur at the time of breakage, probably because of poor compatibility with general-purpose prepreg.

Therefore, the present invention overcomes the above problems and makes a large deformation by combining a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin, an isocyanate modified epoxy resin and a copolyester resin. Resin composition for a composite material, which is excellent in proof stress against, and even when broken by large deformation, brings about a composite material in which cracks and peeling can remain locally.
An object is to provide an intermediate material for a composite material and a composite material.

Further, according to the present invention, a phenol novolac type epoxy resin and / or a cresol novolac type epoxy resin is combined with the above resin composition,
To provide a resin composition for a composite material, an intermediate material for a composite material, and a composite material, which have excellent proof stress against a large deformation and can provide a composite material in which cracks and peeling can remain locally even if broken due to the large deformation. To aim.

Furthermore, the present invention provides a composite material which is excellent in proof stress against large deformation by combining these resin compositions with an antifoaming agent, and in which even if the resin composition is broken due to large deformation, cracks and peeling remain locally. An object of the present invention is to provide a resin composition for composite material, an intermediate material for composite material, and a composite material.

[0011]

The first invention of the present invention comprises:
(A) 100 parts by weight of bisphenol A type epoxy resin and / or bisphenol F type epoxy resin, (C) isocyanate modified epoxy resin 70 to 150
Parts by weight, (D) 3 to 45 parts by weight of copolyester resin, and (E) 5 to 25 parts by weight of epoxy resin curing agent,
The present invention relates to a resin composition for a composite material containing as an essential component.
The second invention of the present invention further comprises (B) the composition of the first invention.
The present invention relates to a resin composition for a composite material containing 85 parts by weight or less of a phenol novolac type epoxy resin and / or a cresol novolac type epoxy resin, and a compounding amount of an isocyanate-modified epoxy resin of 50 to 150 parts by weight. A third invention of the present invention relates to a resin composition for a composite material, wherein the composition of the first invention or the second invention further contains (F) an antifoaming agent in an amount of 1 to 1000 ppm (composition total amount basis).
A fourth invention of the present invention relates to an intermediate material for a composite material obtained by impregnating a reinforcing fiber with the composition of any one of the first to third inventions. A fifth invention of the present invention relates to a composite material obtained by molding the intermediate material of the fourth invention. Hereinafter, the content of the present invention will be described in more detail.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION As the bisphenol A type epoxy resin and / or the bisphenol F type epoxy resin of the component (A) in the present invention, solid ones, semisolid ones, and liquid ones at 20 ° C. are appropriately used. When a bisphenol A type epoxy resin or a bisphenol F type epoxy resin which can be used in combination and is preferably liquid at 20 ° C. is used as a part of the component (A), the viscosity of the obtained resin composition of the present invention can be easily adjusted. Become. The mixing ratio of the bisphenol A type epoxy resin and the bisphenol F type epoxy resin is 100: 0 to 0: 100.

Further, when a low-viscosity bisphenol F type epoxy resin is used in combination with the component (A), crystallization of the resin component does not occur in the winter as in the case of using the bisphenol A type epoxy resin alone. It is not difficult to handle when transferring money.

Examples of the bisphenol A type epoxy resin which can be used in the present invention include liquid ones at 20 ° C., semi-solid ones and solid ones. For example, liquid ones such as Epicoat 825 and Epicoat 827, Epicoat 828 (trade name, manufactured by Japan Epoxy Resin Co., Ltd.), Epotote YD128 (trade name, manufactured by Toto Kasei Co., Ltd.), Epicron 840, Epicron 850, Epicron 855 (trade name, manufactured by Dainippon Ink and Chemicals, Inc.),
DER330, DER331, DER332 (each trade name, manufactured by The Dow Chemical Company), Araldite CY205, Araldite CY230, Araldite CY232, Araldite CY221, Araldite GY257, Araldite GY252, Araldite GY255, Araldite GY250, Araldite GY260, Araldite GY280 (each product name, Asahi Kasei Epoxy Co., Ltd., etc. can be used.
(Trade name, manufactured by Japan Epoxy Resin Co., Ltd.) and the like can be used, and as solid substances, Epicoat 1001, Epicoat 1002, Epicoat 1004, Epicoat 1009.
(Each brand name, manufactured by Japan Epoxy Resin Co., Ltd.), Epotote YD011, Epotote YD012, Epotote Y
D014, Epotote YD017, Epotote YD01
9, Epototo YD020 (each trade name, manufactured by Toto Kasei Co., Ltd.), Epicron 860, Epicron 1050, Epicron 3050, Epicron 4050, Epicron 705
0 (trade name, manufactured by Dainippon Ink and Chemicals, Inc.), DER
662, DER662U, DER663U (trade names, manufactured by Dow Chemical Co.), Araldite GY6071,
Araldite GY7071, Araldite GY7072
(Trade names, manufactured by Asahi Kasei Epoxy Co., Ltd.) and the like can be used.

As examples of the bisphenol F type epoxy resin, Epicoat 806, Epicoat 807 (manufactured by Japan Epoxy Resins Co., Ltd.), Epotote YDF170 (manufactured by Toto Kasei Co., Ltd.), Epicron 830, Epicron 830.
S, Epicron 830LVP, Epicron 835, Epicron 835LV (manufactured by Dainippon Ink and Chemicals, Inc.) and the like are commercially available, and these are all 2
It is liquid at 0 ° C.

The component (B) phenol novolac type epoxy resin and cresol novolac type epoxy resin used in the present invention are liquid at room temperature (20 ° C.), semi-solid, solid or a combination thereof. Can be used. Ingredient ratio of component (B) is 85
It is preferably not more than 20 parts by weight, more preferably 20 parts by weight.
˜55 parts by weight.

When the component (B) is used, the glass transition temperature is improved and the heat resistance is improved. When the amount of the component (B) is more than 85 parts by weight, the tack of the prepreg becomes weak and the workability is improved. Sex problems, and
The obtained molded body is not preferable because the glass transition temperature becomes too high and the resin becomes brittle.

As the above-mentioned phenol novolac type epoxy resin, those which are liquid at 20 ° C., semi-solid and solid can be used.
(Product name, made by Japan Epoxy Resin Co., Ltd.), DEN43
1, DEN438 (trade name, manufactured by Dow Chemical Co., Ltd.),
Epiclon N-738 (trade name, manufactured by Nippon Kayaku Co., Ltd.) and the like can be used, and as semi-solid ones, Epicoat 154 (trade name, manufactured by Japan Epoxy Resin Co., Ltd.), Epotote YD
PN-638 (trade name, manufactured by Tohto Kasei Co., Ltd.), DEN439
(Trade name, manufactured by Dow Chemical Co., Ltd.), Epiclon N-740
(Trade name, manufactured by Nippon Kayaku Co., Ltd.) can be used, and as solid ones, Epotote YDPN-601 and Epotote YD
PN-602 (trade name, manufactured by Tohto Kasei Co., Ltd.), Epicron N-770, Epicron N-775, EPPN-20
1 (each trade name, manufactured by Nippon Kayaku Co., Ltd.) and the like can be used.

As the cresol novolac type epoxy resin, those solid at 20 ° C. are generally known, and Epototo YDCN701, Epotote YDCN702,
Epotote YDCN703, Epotote YDCN704
(Each product name, manufactured by Tohto Kasei Co., Ltd.), Epicron N-66
0, Epicron N-665, Epicron N-667, Epicron N-670, Epicron N-673, Epicron N-680, Epicron N-690, Epicron N-1695 (each trade name, manufactured by Dainippon Ink and Chemicals, Inc.), ESC
N-195X, ESCN-220 (each trade name, manufactured by Sumitomo Chemical Co., Ltd.), EOCN-1020, EOCN-102.
5, EOCN-1027, EOCN-102S, EOC
N-103S, EOCN-104S (trade name, manufactured by Nippon Kayaku Co., Ltd.) and the like can be used.

As the isocyanate-modified epoxy resin as the component (C), XAC4151, AER4152 (each trade name, manufactured by Asahi Kasei Epoxy Co., Ltd.) and the like can be used. The isocyanate-modified epoxy resin is an epoxy resin having an oxazolidone ring, and the lower limit of the epoxy equivalent of this isocyanate-modified epoxy resin can be 200, preferably 300, and the upper limit of this epoxy equivalent is 850, preferably It can be 600.

In the present invention, the component (C) is used for improving tack and adhesiveness, and the blending ratio of the component (C) is
Slightly different depending on the amount of component (B) used. It is preferably 50 to 150 parts by weight, more preferably 90 to 125 parts by weight when the component (B) is used, and preferably 70 to 150 parts by weight when the component (B) is not used. , And more preferably 90 to 125 parts by weight.

As the copolymerized polyester resin as the component (D), commercially available products can be used. As an example, Unitika Elitel UE3350, Unitika Elitel UE3380, Unitika Elitel UE362
0, Unitika Elitel UE3660, Unitika Elitel UE3203 (each product name, manufactured by Unitika), Byron GM900 (product name, manufactured by Toyobo Co., Ltd.) can be used.

The molecular weight of the copolyester resin as the component (D) is 10,000 to 35,000, preferably 15,000.
Can be up to 30,000. Molecular weight is 10,000
If it is less than 3, the tack of the cured product becomes too strong, and if it exceeds 35,000, it becomes difficult to dissolve it in the epoxy resin, which is not preferable. The glass transition temperature of the copolyester resin can be -30 to 90 ° C, preferably 5 to 65 ° C. If the glass transition temperature is lower than -30 ° C, the tack becomes too strong, and if it exceeds 90 ° C, it becomes difficult to dissolve in the epoxy resin, which is not preferable. The acid value of the copolyester resin can be 1 to 10, preferably 1 to 4. If it exceeds 10, hydrolysis tends to occur when the epoxy resin is heated and dissolved, which is not preferable.

In the present invention, the blending ratio of the component (D) used for tack adjustment, drape adjustment and viscosity adjustment of the resin mixture (resin composition) is preferably 3 to 45 parts by weight, more preferably It is preferably 5 to 25 parts by weight.

If the blending ratio of the component (D) is less than the above range, the effect of addition is not observed, and if it exceeds the above range, the mixing property of the component is deteriorated during the production of the resin blend, and bubbles are contained in the resin. It is not preferable because it tends to remain, and the physical properties of the resin decrease, particularly the glass transition temperature and elastic modulus decrease.

The bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin and cresol novolac type epoxy resin used in the present invention are liquid at room temperature (20 ° C.),
A semi-solid type or a solid type can be used. In the present invention, the viscosity of the resin composition can be adjusted by appropriately mixing a liquid, semi-solid, or solid resin at 20 ° C. as the component (A) and / or the component (B). Preferably, it is liquid as the component (A) at 20 ° C.,
The bisphenol A type epoxy resin and the bisphenol F type epoxy resin are used for at least a part, and as the component (B), a liquid type at 20 ° C., a semi-solid type or a solid type is appropriately mixed for handling. The viscosity of the resin composition can be easily adjusted.

For example, liquid resin Epototo YDF170 (trade name, manufactured by Toto Kasei Co., Ltd.) or Epicoat 828 (trade name, manufactured by Japan Epoxy Resins Co., Ltd.) and solid Epicoat 1001 (trade name, Japan Epoxy Resins) are used as the component (A). (1) Liquid Epicoat 152 (trade name, manufactured by Japan Epoxy Resins Co., Ltd.), DEN431 (trade name, manufactured by Dow Chemical Co., Ltd.), and (2) Semi-solid Epicoat 154 as component (B). (Product name, made by Japan Epoxy Resin Co., Ltd.), Epotote YDP
N638 (trade name, manufactured by Tohto Kasei Co., Ltd.) or DEN438
(Trade name, manufactured by Dow Chemical Co., Ltd.) or (3) solid Epotote YDCN701 (trade name, manufactured by Toto Kasei Co., Ltd.) can be appropriately combined. With these components (A),
A resin composition obtained by further mixing and dissolving a copolymerized polyester resin of component (D) in a mixed component of at least one of component (B) exemplified in (1) to (3) and component (C). The viscosity can be adjusted so that the viscosity at 30 ° C. is in the range of 10 to 70 kPa · s.

As the component (B), the above (1) to
The substances exemplified in (3) may be used alone or in combination of two or more. As the epoxy resin curing agent of the component (E), dicyandiamide alone or dicyandiamide and a curing accelerator, for example, 3-
Used in combination with derivatives of (3,4-dichlorophenyl) -1,1-dimethylurea, 3- (4-chlorophenyl) -1,1-dimethylurea, 3-phenyl-1,1-dimethylurea, etc. can do. The mixing ratio of the component (E) is 5 to 25 parts by weight, preferably 6 to
20 parts by weight.

When the amount of the component (E) used for curing the epoxy resin is less than 5 parts by weight, the curing of the resin becomes slow when the composite material is molded and processed, and the molding takes time, and the obtained cured product is obtained. The glass transition temperature of (composite material) becomes low, and excellent mechanical properties of the composite material cannot be obtained.
If it exceeds 25 parts by weight, the resin will be hardened too quickly during molding into a composite material, and it will be difficult to stably obtain a molded product, which is not preferable. In addition to the curing agent of component (E), other curing agents and curing accelerators can be further added if necessary.

As a curing agent which can be further compounded in addition to the component (E), imidazole compounds, diaminodiphenyl sulfone, diaminodiethylbenzene and the like can be further compounded as a curing accelerator in addition to the component (E). Examples thereof include boron trifluoride complexes such as boron chloride monoethylamine and boron trichloride complexes.

As the defoaming agent of the component (F), a silicone defoaming agent is preferable, and as the type of the silicon defoaming agent, an oil type defoaming agent, a compound type defoaming agent, a solution type defoaming agent and the like are used. Among them, the oil type silicone defoaming agent and the solution type silicon defoaming agent are preferably used. Commercially available products can be used as the silicone antifoaming agent, and examples of the oil type silicone antifoaming agent are Shin-Etsu Silicone KF6702 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), SH2.
00 (trade name, manufactured by Toray Dow Corning Silicone Co., Ltd.), and Shinetsu Silicone KS603 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), SD55 as an example of the solution type silicone defoaming agent.
91, SH7PA (each trade name, manufactured by Toray Dow Corning Silicone Co., Ltd.) and the like.

The blending ratio of the component (F) is 1 to 1000 ppm (0.0001 to 0.1% by mass), preferably 20 to 200 ppm (0.002 to 0.002) based on the total amount of the composition.
0.02% by mass).

When the component (F) used for defoaming the epoxy resin exceeds 1000 ppm, a small amount of silicone remains on the surface of the cured molded body during molding of the composite material, which adheres to another substrate or It becomes an obstacle when painting and is not preferable.

In the resin composition for composite materials (epoxy resin composition) of the present invention, other epoxy resins, toughness-imparting resins, fillers, colorants and the like can be blended within a range that does not impair the performance thereof.

Epoxy resins which can be optionally contained in the resin composition of the present invention include resorcin type epoxy resins, hydroquinone type epoxy resins, aromatic amine type epoxy resins, aromatic glycidyl ester type epoxy resins. , Naphthalene type epoxy resin, biphenyl type epoxy resin and the like can be used.

As the resorcin-type epoxy resin, Denacol EX-201 (trade name, manufactured by Nagase Kasei Co., Ltd.),
Denacol EX as a hydroquinone type epoxy resin
-203 (trade name, manufactured by Nagase Chemical Industry Co., Ltd.) and the like.

As the aromatic amine type epoxy resin,
Sumi-epoxy ELM434 (trade name, manufactured by Sumitomo Chemical Co., Ltd.), which is tetraglycidyl diaminodiphenylmethane, Epototo YH434L, Epototo YH434 (trade name, manufactured by Toto Kasei Co., Ltd.), Araldite MY720 (trade name, manufactured by Asahi Kasei Epoxy Corporation), triglycidyl Aminophenol Sumi-epoxy ELM100, Sumi-epoxy ELM120 (each trade name, manufactured by Sumitomo Chemical Co., Ltd.), diglycidylaniline GAN (trade name, manufactured by Nippon Kayaku Co., Ltd.), diglycidyl orthotoluidine GOT (product) Name, manufactured by Nippon Kayaku Co., Ltd., etc.

As the aromatic glycidyl ester type epoxy resin, o-phthalic acid diglycidyl ester Denacol EX-721 (trade name, manufactured by Nagase Kasei Co., Ltd.) and terephthalic acid diglycidyl ester Denacol EX-711 ( Product name, manufactured by Nagase Kasei Co., Ltd.) and the like.

The naphthalene type epoxy resin is 1,
Epiclon HP-4032H (trade name, manufactured by Dainippon Ink and Chemicals, Inc.), which is 6-dihydroxynaphthalene diglycidyl ether, may be mentioned.

As the biphenyl type epoxy resin, 4,
Epicoat YX4000 which is 4'-dihydroxy-3,3 ', 5,5'-biphenyldiglycidyl ether
(Product name, made by Japan Epoxy Resin Co., Ltd.), 4, 4'-
Epicoat YL61 which is a mixture of dihydroxy-3,3 ', 5,5'-biphenyl diglycidyl ether and 4,4'-dihydroxybiphenyl diglycidyl ether
21H (trade name, manufactured by Japan Epoxy Resins Co., Ltd.) and the like.

As the toughness-imparting resin which can be optionally contained in the resin composition of the present invention, reactive elastomer, Hiker CTBN-modified epoxy resin, Hiker C
Examples thereof include TB-modified epoxy resin, urethane-modified epoxy resin, nitrile rubber-added epoxy resin, silicone-modified epoxy resin, and thermoplastic elastomer-added epoxy resin.

As the filler which can be optionally contained in the resin composition of the present invention, mica, alumina,
Talc, finely divided silica, wollastonite, sepiolite, basic magnesium sulfate, calcium carbonate, polytetrafluoroethylene powder, zinc dust, aluminum powder,
Examples thereof include organic fine particles, that is, acrylic fine particles, epoxy resin fine particles, polyamide fine particles, polyurethane fine particles and the like.

The colorant which can be optionally contained in the resin composition of the present invention includes organic pigments such as azo pigments, phthalocyanine pigments, quinacridone pigments, anthraquinone pigments, and other inorganic pigments such as dioxide. Titanium, yellow lead, cobalt violet, red iron oxide, carbon black, pearl pigment and the like can be mentioned.

The method for producing the resin composition according to the present invention is not particularly limited. For example, the resin components (A), (C) and (D) (in the case of the second invention, the component (B) is further mixed). )
Is preferably mixed at 150 to 200 ° C., and then the resin temperature is lowered to 85 ° C. or lower by cooling or natural heat radiation, and then the curing agent component (E) and the defoaming agent component (F) are added. Since moisture and terminal carboxyl groups in the copolyester resin are used to prevent deterioration due to hydrolysis caused by heating for a long time, the polycarbodiimide resin powder is used in an amount of 0.1 to 1% with respect to the amount of the component (D).
By adding it, the hydrolysis resistance effect can be exhibited. When the component (E) is in the form of a solid powder such as dicyandiamide, if the component (E) is mixed with a part of the liquid epoxy resin component such as the component (A) before the mixing, the component (E) ) Can be easily dispersed in the resin composition. Further, a method of vacuum degassing and mixing while stirring is preferably adopted for the purpose of reducing the generation of voids after molding.

When the curing agent component (E) is added and mixed at a resin temperature higher than 90 ° C., the curing agent component (E)
Is partially dissolved in the resin, the resin and the curing agent are likely to react with each other, and the storage stability of the intermediate material for a composite material formed by impregnating the resin composition into the reinforcing fiber is significantly impaired.

In the present invention, the above component (A),
A resin composition containing (C), (D) and (E) (in the case of the second invention, further contains the component (B)) or a resin composition containing the components (A) to (F). Is impregnated into the reinforcing fiber to form an intermediate material (prepreg) for a composite material.

The reinforcing fiber is not particularly limited, and all fibers generally used as the reinforcing fiber of the composite material can be used. For example, carbon fibers, glass fibers, aramid fibers, boron fibers, silicon carbide fibers, and surface-treated (ozone-treated, plasma-treated) organic fibers, or
It is possible to use fibers having a hybrid structure of two or more selected from these. In particular, a laminated body in which prepregs obtained by impregnating carbon fibers having different elastic moduli such as polyacrylonitrile-based (PAN-based) carbon fibers and pitch-based carbon fibers with the resin-containing composition of the present invention are preferable, and particularly, tensile elasticity Rate 30-200 GPa
Low elastic modulus prepreg, tensile elastic modulus 200-600GP
a PAN-based carbon fiber prepreg and tensile modulus of 50
A laminate in which pitch-based carbon fiber prepregs having a high elastic modulus of 0 to 1000 GPa are appropriately combined and laminated, or a low-modulus prepreg having a tensile elastic modulus of 30 to 200 GPa and a pitch-based carbon fiber having a high elastic modulus of 500 to 1000 GPa. A laminate in which prepregs are appropriately combined and laminated is preferably used because a lightweight and highly functional molded product (composite material) can be obtained from each laminate.

The form of the reinforcing fiber prepreg is not particularly limited and can be appropriately selected according to the purpose. For example,
A unidirectional prepreg, a woven prepreg, a braided woven prepreg, a non-woven prepreg, or the like can be used.

In the present invention, the method of impregnating the reinforcing fiber with the resin composition is not particularly limited, but the resin composition is usually heated to 60 to 90 ° C. to impregnate the reinforcing fiber.
A so-called hot melt method is preferably adopted.

The content of the resin composition of the intermediate material thus produced is usually 20 to 50% by mass, preferably 25 to 45% by mass, based on the total amount of the reinforcing fiber and the resin composition.

The intermediate material is finally formed into a composite material.
For example, a laminate obtained by laminating intermediate materials is usually used in an autoclave or a pressure press to obtain 110 to 150
A composite material can be obtained by heating and curing at 30 ° C. for 30 minutes to 3 hours. The obtained composite material has a stable quality, is uniform, and has few voids, even though the curing agent component (E) is a dispersion system.

Examples of the use of the composite material include golf shafts, tennis rackets, ski poles, printing ink rolls, bicycle pipes, pressure vessels, conveying members and the like. Above all, the composite material of the present invention is suitable for a golf shaft. That is, in recent years, the weight reduction of golf shafts has progressed, and the usage conditions thereof have become severe, making it difficult for conventional shafts to satisfy both weight reduction and excellent impact resistance.

The golf shaft obtained according to the present invention is lighter in weight than conventional products and can withstand severe usage conditions.

[0054]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. The test methods used in Examples and Comparative Examples are as follows.

(Long-span Bending Test) A long-span three-point bending test of a straight pipe test piece was carried out by using Tensilon, a universal capability tester manufactured by Orientec Co., Ltd. The size of the test piece had an inner diameter of 10 mm and a length of 1200 mm, and the distance between the fulcrums (span) was 600 mm.

(Torsion Test) A twist test of a straight pipe test piece was performed using a twist tester compliant with SG standard (certification standard and standard confirmation method for golf club shafts). The size of the test piece is 400 mm
The test was conducted with a length of mm and a distance (span) between fulcrums of 300 mm.

(Impact Test) Impact of a straight pipe test piece 3 using an instrumentation falling weight impact tester manufactured by Yonekura Seisakusho Co., Ltd.
A point bending test was performed. The size of the test piece is φ10
mm, 400 mm length, distance between fulcrums (span) is 3
The test was performed at 00 mm.

Examples 1-8 and Comparative Examples 1-4 Epoxy resin compositions having the compositions shown in Tables 1 to 3 were prepared,
A low elastic modulus carbon fiber (trade name: XN-05, XN-10) manufactured by Nippon Graphite Fiber Co., Ltd. was impregnated with the resin composition to produce a unidirectional prepreg (100 g of fiber weight, resin content 33%). In addition, Nippon Graphite Fiber Co., Ltd. high elastic modulus carbon fiber (trade name: YSH-
No. 60, YS-80) was impregnated with the resin composition to produce a unidirectional prepreg (100 g of fiber basis weight, resin content 33%).

The unidirectional prepreg using YSH-60 or YS-80 was applied to a cored bar having an outer diameter of 10 mmφ, and two layers each were formed so that the carbon fibers were oriented in a direction of ± 45 ° with respect to the axial direction of the cored bar. A single layer of the unidirectional prepreg using XN-05 or XN-10 was wound so that the carbon fibers were oriented in the 0 ° direction (axial direction).
From above, a general-purpose prepreg P30 manufactured by Toray Industries, Inc.
Two layers of 52S-12 (T700S / 125 g of fiber weight / 33% of resin content) are wound so that the reinforcing fibers are oriented in the 0 ° direction (axial direction), and a uniaxially stretched tape of PP (polypropylene) is further wound on it. The obtained laminate was heated in a drying oven at 130 ° C. for 1 hour to be cured.
The obtained molded pipe is 1200 mm long and 400 mm
Each was cut into a length to obtain a test piece. The long-span three-point bending test, the twisting test, and the impact test of the obtained pipe test piece were performed.

[0060]

[Table 1]

[0061]

[Table 2]

[0062]

[Table 3]

Numerical units of each component other than the component (F) in the table are parts by weight. The numerical unit of the component (F) is mass%. As is clear from Table 1 and Table 2, a prepreg using a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin, an isocyanate modified epoxy resin and a copolyester resin, and in addition to these resins, a phenol novolac type epoxy resin and / or Or prepregs using cresol novolac type epoxy resin, and further, prepregs obtained by adding an antifoaming agent to these resins have high elongation and toughness of the resin, so long-span bending test, torsion test, impact test Since the load was high and the energy due to the flexure at the time of breaking was able to be absorbed, almost no peeling between the layers of the prepreg was observed after the breaking. Fix one end of the pipe test piece and apply a torque to the other end.The load at the time when this pipe test piece breaks torsionally is defined as the load at the time of torsional breakage, and the twisting angle at that time Expressed as an angle.

On the other hand, as in the comparative example of Table 3, a prepreg which does not use an isocyanate-modified epoxy resin and a copolyester resin (Comparative Example 1) and a prepreg which uses a phenoxy resin instead of the copolyester resin (Comparative Example 2) In 3 and 4), since the elongation and toughness of the resin are insufficient, the load at break in the long span bending test, the torsion test, and the impact three-point bending test is low, and the energy due to deflection at break cannot be absorbed. However, after the breakage, large peeling occurred between the layers of the prepreg.

[0065]

According to the resin composition for a composite material of the present invention, it is possible to obtain a composite material having an excellent proof stress against a large deformation which cannot be achieved by the conventional epoxy resin for prepreg, and the resin of the present invention. The intermediate material for composite materials obtained by using the composition is excellent in handleability and has particularly suitable drapeability. INDUSTRIAL APPLICABILITY The resin composition for a composite material of the present invention is excellent as a resin composition for a composite material and an intermediate material for a composite material, and is particularly excellent as a resin composition for FRP, CFRP and an intermediate material used therefor. It is a thing.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) // (C08L 63/00 B29K 63:00 67:00) B29C 67/14 W B29K 63:00 F term (reference) 4F072 AA04 AA07 AB10 AB22 AD27 AD28 AD33 AE01 AE06 AG03 AG17 AH02 AH21 AK06 AK11 AL05 4F205 AA24 AA39 AB03 AB10 HA19 HA33 HA35 4J002 CD05W CD063 CD20X CF004 CP035 FD40 FD060 FD140 FD060 FD140 FD060 DC31 FB11 FB16 JA11

Claims (5)

[Claims] 1. (A) Bisphenol A type epoxy resin and / or bisphenol F type epoxy resin 100
70 to 150 parts by weight of (C) isocyanate-modified epoxy resin, (D) 3 to 45 parts by weight of copolyester resin, and (E) 5 to 5 parts by weight of epoxy resin curing agent.
A resin composition for a composite material, containing 25 parts by weight as an essential component. 2. Further, (B) a phenol novolac type epoxy resin and / or a cresol novolac type epoxy resin of 85 parts by weight or less is contained as an essential component, and the compounding amount of the isocyanate-modified epoxy resin is 50 to 150 parts by weight. Item 2. A resin composition for a composite material according to Item 1. 3. The resin composition for a composite material according to claim 1, further comprising 1 to 1000 ppm of (F) antifoaming agent as an essential component based on the total amount of the composition. 4. An intermediate material for a composite material obtained by impregnating a reinforcing fiber with the resin composition for a composite material according to any one of claims 1 to 3. 5. A composite material obtained by molding the intermediate material for a composite material according to claim 4.