JP2003041093A - Resin composition for composite material, intermediate material for composite material and composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for composite materials giving excellent yield strength resistant to a large deformation to the composite materials, to provide an intermediate material for composite materials and a composite material having excellent mechanical properties. SOLUTION: The resin composition for composite materials includes 1-15 pts.wt. of organic fine particles, 3-45 pts.wt. of a polyester copolymer resin and 5-25 pts.wt. of an epoxy resin-curing agent based on 100 pts.wt. of a bisphenol-A epoxy resin and/or a bisphenol-F epoxy resin. In addition to these resin components, <=85 pts.wt. of a phenol novolak modified epoxy resin and/or a cresol novolak modified epoxy resin are combined to give the resin composition for composite materials. In another embodiment, 1-1,000 ppm of a defoaming agent is admixed to the resin composition for composite 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.

Further, in recent years, such composite materials have been increasingly used in sports equipment, particularly golf shafts.

Composite materials such as reinforced fiber plastic (FRP) and carbon fiber reinforced plastic (CFRP) are made into prepreg by impregnating a reinforced fiber base material such as carbon fiber, glass fiber, aramid fiber or boron fiber with a matrix resin. 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 fiber 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, a polyfunctional epoxy resin has a short inter-crosslinking distance, and therefore has a high glass transition temperature, which results in high heat resistance, interlaminar shear strength (ILSS) and bending strength of the obtained molded product. 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.

[0007]

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.

As a means for improving the proof stress and the impact resistance against large deformation, there is known one in which a thermoplastic resin such as polyether sulfone or nylon or a rubber modified resin is added. 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 carbon fibers are used as a part of the laminated structure, peeling may occur at the time of breakage, probably due to poor compatibility with a general-purpose prepreg.

In view of the above, the present invention overcomes the above problems and combines bisphenol A type epoxy resin and / or bisphenol F type epoxy resin, organic fine particles, and copolyester resin to withstand large deformation. It is an object of the present invention to provide a resin composition for a composite material, an intermediate material for a composite material, and a composite material, which are excellent in heat resistance, and can provide a composite material in which cracks and peeling can remain locally even if they are damaged by large deformation.

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 which is capable of retaining cracks and peeling locally even if the resin composition is broken due to large deformation. 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.

[0012]

The first invention of the present invention comprises:
(C) 1 to 15 parts by weight of organic fine particles, (D) 3 to 45 parts by weight of copolyester resin, and (E) to 100 parts by weight of bisphenol A type epoxy resin and / or bisphenol F type epoxy resin. ) It relates to a resin composition for a composite material, which contains 5 to 25 parts by weight of an epoxy resin curing agent as an essential component. A second invention of the present invention relates to a resin composition for a composite material, wherein the composition of the first invention further contains (B) not more than 85 parts by weight of a phenol novolac type epoxy resin and / or a cresol novolac type epoxy resin. A third invention of the present invention is the composition of the first invention or the second invention, further comprising (F) an antifoaming agent of 1 to 1000 ppm.
The present invention relates to a resin composition for a composite material containing (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.

[0013]

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. 827, Epicoat 828 (trade name, manufactured by Japan Epoxy Resins 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 Tohto 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
(Each product name, 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 830S, Epicron 830LVP, Epicron 835, Epicron 83.
The commercially available products such as 5LV (manufactured by Dainippon Ink and Chemicals, Inc.) are listed, and all of them are liquid at 20 ° 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, resulting in a problem in workability, and the obtained molded product has an excessively high glass transition temperature.
It is not preferable because the resin becomes brittle.

As the above-mentioned phenol novolac type epoxy resin, those which are liquid at 20 ° C., semisolid 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 Epotote YDCN701, Epotote YDCN702,
Epotote YDCN703, Epotote YDCN704
(Each product name, manufactured by Tohto Kasei Co., Ltd.), Epicron N-66
0, Epiclone N-665, Epiclone N-667, Epiclone N-670, Epiclone N-673, Epiclone N-680, Epiclone N-690, Epiclone 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 organic fine particles of component (C), thermosetting resin fine particles, thermoplastic resin fine particles, or a mixture thereof can be used. Examples of the thermosetting resin fine particles include epoxy resin fine particles, phenol resin fine particles, melamine resin fine particles, urea resin fine particles, silicone resin fine particles, urethane resin fine particles, or a mixture thereof. Among them, epoxy resin fine particles and silicone resin fine particles are preferable. Can be used. Commercially available Trepal EP (trade name, manufactured by Toray) is used as the epoxy resin particles, and Trefil E is used as the silicone resin particles.
(Product name, manufactured by Toray Dow Corning Silicone Co., Ltd.),
Tospearl (trade name, manufactured by Toshiba Corporation), X-52-854
(Trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) and the like.

Examples of the thermoplastic resin fine particles include acrylic fine particles, butadiene-acrylonitrile resin fine particles, styrene fine particles, olefin fine particles, nylon fine particles, or a mixture thereof. Among them, acrylic fine particles can be preferably used because they have good dispersibility in an epoxy resin. As a method for producing acrylic fine particles, there are (1) monomer polymerization, (2) polymer chemical treatment method, (3) polymer mechanical pulverization method, and the like.
The method (3) is not preferable because a fine product cannot be obtained and the shape is irregular. Polymerization methods include emulsion polymerization, soap-free emulsion polymerization, dispersion polymerization, seed polymerization, suspension polymerization, and methods in which these are used in combination, and the particle size is fine, partially crosslinked structure, core / shell structure, hollow Emulsion polymerization or seed polymerization is used to obtain fine particles having a structure and a polar structure (epoxy group, carboxyl group, hydroxyl group, etc.). Partially crosslinked fine particles and core / shell type fine particles obtained by these are preferably used. Examples of the partially crosslinked fine particles include partially crosslinked acrylic fine particles and partially crosslinked polystyrene fine particles, which are commercially available.
Examples include type (trade name, manufactured by Soken Chemical Co., Ltd.), eposter MA (trade name, manufactured by Nippon Shokubai Co., Ltd.), and Matsumoto Microsphere M series (trade name, manufactured by Matsumoto Yushi-Seiyaku Co., Ltd.). As commercially available core / shell type fine particles, Staphyloid AC3355 (trade name, manufactured by Takeda Pharmaceutical Co., Ltd.), F351 (trade name, manufactured by Nippon Zeon Co., Ltd.), Kureha Paraloid EXL-2655 (trade name, Kureha Chemical Co., Ltd.) (Manufactured by Kogyo Co., Ltd.) and the like.

In the present invention, the compounding ratio of the component (C) used for improving the toughness of the resin is preferably 1 to 15 parts by weight, more preferably 3 to 10 parts by weight. The particle size of the organic fine particles as the component (C) is 10
It can be set to less than or equal to μm, preferably less than or equal to 5 μm.

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 Epotote YDF170 (trade name, manufactured by Toto Kasei Co., Ltd.) or Epicoat 828 (trade name, manufactured by Japan Epoxy Resins Co.) 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.) or Epotote YDPN638 (trade name, Toto Kasei Co., Ltd.) Manufactured), (2) semi-solid Epicoat 154 (trade name, manufactured by Japan Epoxy Resins Co., Ltd.) or DEN43
8 (trade name, manufactured by Dow Chemical Co., Ltd.) or (3) solid epotote YDCN702 (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,
Examples thereof include talc, fine powder silica, wollastonite, sepiolite, basic magnesium sulfate, calcium carbonate, polytetrafluoroethylene powder, zinc dust, and aluminum powder.

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, the component (C) can be easily dispersed in the resin composition by heating and mixing the component (C) with a part of the liquid resin component (A) at room temperature at 150 to 170 ° C. Further, for the purpose of reducing the generation of voids after molding, a method of vacuum degassing and mixing while stirring is preferably adopted.

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 laminate obtained by laminating a prepreg obtained by impregnating a polyacrylonitrile-based (PAN-based) carbon fiber and a pitch-based carbon fiber, in particular, a pitch-based carbon fiber of 30 to 950 GPa with the present resin compounding composition is obtained from this laminate. It is preferably used since a lightweight and highly functional molded product (composite material) can be obtained.

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,
Low elastic modulus carbon fiber (CF) (trade name: XN-05, XN-10) manufactured by Nippon Graphite Fiber Co., Ltd. is impregnated with the resin composition to form a unidirectional prepreg (fiber basis weight 10
0 g, resin content 33%) was produced. Also, Nippon Graphite Fiber Co., Ltd. high modulus carbon fiber (trade name:
YSH-60, YS-80) was impregnated with the above resin composition to form a unidirectional prepreg (100 g of fiber weight, resin content 3).
3%).

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 P3052S-12 (T700S / fiber basis weight 12) manufactured by Toray Industries, Inc.
5g / resin content 33%) is wound in two layers so that the reinforcing fibers are oriented in the 0 ° direction (axial direction), and then PP
A uniaxially stretched tape of (polypropylene) was wound, and the obtained laminate was heated and cured at 130 ° C. for 1 hour in a drying oven. The obtained molded pipe was cut into a length of 1200 mm and a length of 400 mm 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.

[0061]

[Table 1]

[0062]

[Table 2]

[0063]

[Table 3]

The numerical unit of each component other than the component (F) in the table is parts by weight. The numerical unit of the component (F) is mass%. As is clear from Tables 1 and 2, a prepreg using a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin, organic fine particles and a copolyester resin, a phenol novolac type epoxy resin and / or a cresol in addition to these resins. Prepregs using a 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, twisting test, load at break in impact test Since it is high and it is possible to absorb the energy due to the flexure at the time of breaking, 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 containing no copolyester resin (Comparative Example 1) and a prepreg in which the amount of the copolyester resin was outside the range specified by the present invention (Comparative Example) 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, After the break, large peeling occurred between the layers of the prepreg.

[0066]

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 67:00) B29K 105: 06 B29K 63:00 B29C 67/14 W 105: 06 F term (reference) 4F072 AA04 AA07 AB10 AB22 AD27 AD28 AE01 AE06 AG03 AG17 AH02 AH21 AK06 AK11 AL05 4F205 AA24 AA39 AB03 AB10 AB11 HA19 HA33 HB01 4J002 CD051 CD062 CF003 CP034 ER026 ET016 FD010 DC0716 FD204 GC0531FD06 GC01 31

Claims (5)

[Claims] 1. (A) Bisphenol A type epoxy resin and / or bisphenol F type epoxy resin 100
1 to 15 parts by weight of (C) organic fine particles,
A resin composition for a composite material comprising (D) 3-45 parts by weight of a copolyester resin and (E) 5-25 parts by weight of an epoxy resin curing agent as essential components. 2. The resin composition for a composite material according to claim 1, further comprising (B) not more than 85 parts by weight of a phenol novolac type epoxy resin and / or a cresol novolac type epoxy resin (B) as an essential component. 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.