JP2001011287A - Fiber-reinforced plastic member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a fiber-reinforced plastic member which is lightweight and excellent in tortional strength and in fracture resistance in the fracture mode of collapse by specifying the flexural strength of a fiber-reinforced plastic member which comprises a fibrous reinforcement and a matrix resin formed by curing an epoxy resin composition containing a curing agent. SOLUTION: This member has a 90 deg. flexural strength of 130-180 MPa. Though the use of carbon fibers, as the fibrous reinforcement, is preferable in terms of excellent mechanical strength and durability, glass fibers, etc., surface-treated to enhance the adhesive properties can also be used. Carbon fibers having a surface carboxyl group concentration COOH/C of 0.002-0.02 and a surface specific oxygen concentration O/C of 0.02-0.03 are preferable. An epoxy resin containing 70-100 wt.% of the one having a couple of epoxy groups in molecule is preferable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a member made of fiber-reinforced plastic which can be preferably used for general industrial use, sports and leisure use, and the like.

[0002]

2. Description of the Related Art Fiber-reinforced plastic members made of a reinforcing fiber and a matrix resin are widely used in sports applications, aerospace applications, general industrial applications, etc. due to their excellent mechanical strength. . Particularly in sports applications, golf shafts, fishing rods, rackets for tennis and badminton, sticks for hockey, and the like can be cited as main applications.

[0003] Among sports applications, golf shafts and fishing rods are strongly demanded for weight reduction. For this purpose, it is necessary to increase the strength of a fiber-reinforced plastic member.

[0004] For this purpose, efforts have been made to improve the strength of the reinforcing fiber, and a fiber-reinforced plastic member having a high tensile strength in the direction of the arranged fibers (0 ° direction) has been obtained.

However, a load is applied to the fiber reinforced plastic member in a complicated manner from directions other than the fiber direction. Since the strength characteristics in the direction of the reinforcing fibers do not function effectively with respect to such a load, the strength of the fiber-reinforced plastic member in a direction other than the fiber direction has not been sufficiently satisfied.

In sports applications, carbon fibers and glass fibers are mainly used as reinforcing fibers, and epoxy resins are mainly used as matrix resins. In the production of fiber-reinforced plastic members, a sheet-like intermediate material in which fibers are impregnated with a matrix resin is used. A method using a prepreg as a base material is often used. In this method, after laminating a plurality of prepregs, a molded article is obtained by heating.

When a fiber reinforced plastic member is applied to a golf shaft or a fishing rod, a cylindrical composite material obtained by winding and laminating a unidirectional prepreg whose fiber directions are aligned in one direction in several directions while changing the direction is used. Used in form.
In such a cylindrical composite material, when a force in the bending direction is applied, if a collapse mode of collapse is applied, the strength of the cylindrical composite material in a direction other than the fiber direction is often insufficient, so that Although some measures are taken to take measures such as being easily damaged and increasing the amount of resin used in the outer layer of the prepreg, the measures for reducing the weight described above have been extremely insufficient.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fiber which is excellent in fracture resistance in a crushing failure mode, is lightweight, and has excellent torsional strength, especially when it is made into a cylindrical composite material. It is to provide a reinforced plastic member.

[0009]

The present invention has the following arrangement to achieve the above object. That is, a fiber-reinforced plastic member composed of a reinforcing fiber and a matrix resin obtained by curing an epoxy resin composition,
It is a fiber reinforced plastic member having a 90 ° bending strength of 130 to 180 MPa.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors diligently study the above-mentioned problems, and heat and cure a curing agent, and preferably an epoxy resin composition containing a specific compound, to form a matrix resin. Accordingly, the 90 ° bending strength of the fiber reinforced plastic member becomes higher than ever before, and when such a fiber reinforced plastic member is formed into a cylindrical composite material, the fiber reinforced plastic member has excellent fracture resistance in a crushing failure mode, and is lightweight. It has been found that the properties are ensured and the torsional strength is further improved, and the present invention has been reached.

[0011] The fiber-reinforced plastic member of the present invention comprises:
It is composed of reinforcing fibers and a matrix resin obtained by heating and curing the epoxy resin composition. Here, the epoxy resin is used because it is excellent in heat resistance, water resistance, and adhesion, but other thermosetting resins such as an unsaturated polyester resin may be used.

The reinforcing fiber may be a twisted yarn, untwisted yarn, or non-twisted yarn. However, untwisted yarn or non-twisted yarn is preferable because both the moldability and the mechanical strength of the fiber-reinforced plastic member are compatible. Further, as the form of the reinforcing fiber, one in which the direction of the fiber is aligned in one direction or a woven fabric can be used. The woven fabric can be freely selected from plain weave, satin weave, and the like according to the site to be used and the application.

In the present invention, carbon fibers are preferably used as the reinforcing fibers because of their excellent mechanical strength and durability. Other reinforcing fibers are glass fibers which have been subjected to a surface treatment or the like in order to enhance the adhesiveness. , Aramid fiber,
Boron fiber, alumina fiber, silicon carbide fiber and the like can also be used, and these fibers can be used as a mixture of two or more kinds. Further, the carbon fiber can wrap so-called graphite fiber, and specifically, various types such as polyacrylonitrile type, pitch type and rayon type can be used. Among them, polyacrylonitrile-based ones from which high-strength carbon fibers can be easily obtained are preferably used.

In the present invention, the 90 ° bending strength of the fiber reinforced plastic member made of such a material is 130 to 130.
180 MPa, preferably 13 MPa
5 to 180 MPa, more preferably 140 to 180 MPa
a is good. If it is less than 130 MPa, it is likely to be damaged by the breaking mode of collapse, and 180 MPa
Above the above, the adhesiveness between the reinforcing fiber and the matrix resin (hereinafter simply referred to as adhesiveness) tends to be excessive, and the 0 ° tensile strength may decrease.

When the fiber-reinforced plastic member of the present invention is a cylindrical composite material, the ratio between the inner diameter and the thickness is preferably 0.01 to 200, more preferably 0.1 to 170, and more preferably 0.1 to 170. Is preferably 1 to 150. If it is less than 0.01, the cylindrical composite material cannot achieve both lightness and strength properties, and if it exceeds 200, the torsional strength of the cylindrical composite material may be reduced.

The 90 ° bending strength of the fiber reinforced plastic member can be improved by increasing the adhesiveness.

In order to enhance the adhesiveness, the surface of the reinforcing fiber is modified by some treatment, or the epoxy resin composition is improved to increase the affinity with the surface of the reinforcing fiber. A method in which the used reinforcing fiber and the epoxy resin composition are used in combination can be adopted.

For the modification of the carbon fiber surface as a reinforcing fiber, the following method (1) or (2) can be employed. (1) Adjusting the amount of functional groups on the carbon fiber surface. That is,
Surface specific oxygen concentration measured by X-ray photoelectron spectroscopy (hereinafter abbreviated as O / C), surface carboxyl group concentration measured by chemically modified X-ray photoelectron spectroscopy (hereinafter COOH /
(Abbreviated as C) is a specific range.

Specifically, the O / C on the carbon fiber surface is
It is good to be 0.02 or more, preferably 0.04 or more, more preferably 0.06 or more. When the O / C is less than 0.02, the affinity for a polar group in the matrix resin described below decreases, and the 9
The 0 ° bending strength may not be improved. Furthermore, O / C
Is preferably 0.3 or less, more preferably 0.25 or less. If the O / C exceeds 0.3, the affinity between the carbon fiber and the polar group in the matrix resin becomes stronger, but the oxide layer having a strength considerably lower than the strength originally possessed by the carbon fiber itself is formed by the carbon fiber. To cover the surface of
The resulting fiber reinforced plastic member will have low strength.

On the other hand, the COOH / C of the carbon fiber is 0.002 or more, preferably 0.005 or more. When COOH / C is less than 0.002, the affinity with the polar group in the matrix resin is reduced, and the 90 ° bending strength of the fiber reinforced plastic member may not be improved. Further, the upper limit of COOH / C is 0.03 or less, preferably 0.02 or less. C
When OOH / C exceeds 0.03, although the affinity between the carbon fiber and the polar group in the matrix resin becomes strong, the oxide layer having much lower strength than the carbon fiber itself originally has is formed by the carbon fiber. Therefore, the strength of the resulting fiber-reinforced plastic member is low. Further, the curing speed of the matrix resin may be delayed.

The carbon fibers having the above-specified O / C and COOH / C ranges can be obtained by subjecting them to electrolytic oxidation treatment or oxidation treatment in gas phase or liquid phase. Among them, it is preferable to perform the electrolytic oxidation treatment because the oxidation treatment can be performed in a short time and the oxidation treatment can be easily controlled.

The electrolytic solution used in the electrolytic oxidation treatment may be either acidic or alkaline. Specific examples of the electrolyte dissolved in the acidic electrolyte include inorganic acids such as sulfuric acid and nitric acid, organic acids such as acetic acid and butyric acid, and salts such as ammonium sulfate and ammonium hydrogen sulfate. Among them, sulfuric acid and nitric acid showing strong acidity can be preferably used. Specific examples of the electrolyte dissolved in the alkaline electrolyte include hydroxides such as sodium hydroxide and potassium hydroxide, ammonia, inorganic salts such as sodium carbonate and sodium hydrogen carbonate, and organic salts such as sodium acetate and sodium benzoate. And further potassium salts, barium salts or other metal salts thereof, and ammonium salts,
An organic compound such as tetraethylammonium hydroxide or hydrazine can be used. From the viewpoint of eliminating the obstacle to curing of the resin, ammonium carbonate, ammonium hydrogencarbonate, and tetraalkylammonium hydroxide containing no alkali metal can be preferably used.

The amount of electricity to be supplied can be optimized according to the degree of carbonization of the carbon fibers. From the viewpoint of appropriately suppressing the decrease in the crystallinity of the surface layer, the amount of electricity is 3 to 500.
It is preferably in the range of coulomb / g, more preferably in the range of 5 to 200 coulomb / g.

After the electrolytic oxidation treatment, the yarn is preferably washed with water and dried. At the time of drying, if the temperature is too high, the functional group present on the outermost surface of the carbon fiber is easily lost by thermal decomposition, so it is desirable to set the drying temperature as low as possible,
It is good to dry at 250 ° C. or less, preferably 210 ° C. or less.

Further, by such a treatment, the roughness of the carbon fiber surface can be increased at the same time, whereby the above-mentioned adhesiveness can be enhanced. (2) To reduce the crystal size of the carbon fiber. That is,
The purpose is to make the crystal size Lc of the carbon fiber measured by the wide-angle X-ray diffraction method a specific range and increase the number of active sites.

Specifically, the crystal size Lc of the carbon fibers is preferably 15 to 70 angstroms, preferably 20 to 35 angstroms, and more preferably 20 to 30 angstroms.

In order to produce lightweight sporting goods such as fishing rods and golf shafts, it is preferable to use a carbon fiber having a high elastic modulus so that a small amount of material can exert sufficient rigidity of the product. preferable. From such a viewpoint, the tensile modulus of the carbon fiber is preferably 200 to 800 GP.
a, more preferably 225 to 800 GPa.

According to the present invention, an even greater effect is obtained by heating and curing an epoxy resin composition containing a specific compound to form a matrix resin in order to increase the affinity with the reinforcing fiber surface. It is found that it can be done.

In the present invention, the epoxy resin constituting the matrix resin is a compound having two or more epoxy groups in a molecule.

In the present invention, in order to improve the 90 ° bending strength of the fiber reinforced plastic member, the adhesion is increased and the matrix resin is made of JIS K
High flexural modulus as measured in 7203, JIS
Since it is preferable that the tensile elongation as measured by K7113 is large, the epoxy resin having two epoxy groups in the molecule is used in an amount of 70 to 100% by weight based on 100% by weight of the total epoxy resin in the epoxy resin composition. %, Preferably 80 to 100% by weight.

Specific examples of the epoxy resin in the present invention include glycidyl ether obtained from a polyol, glycidylamine obtained from an amine having a plurality of active hydrogens, glycidyl ester obtained from a polycarboxylic acid, and plural glycidyl esters in a molecule. A polyepoxide obtained by oxidizing a compound having a heavy bond is exemplified.

Specific examples of glycidyl ether include bisphenol A epoxy resin obtained from bisphenol A, bisphenol F epoxy resin obtained from bisphenol F, bisphenol S epoxy resin obtained from bisphenol S, and tetrabromobisphenol A. Bisphenol type epoxy resin such as tetrabromobisphenol A type epoxy resin.

Specific examples of the glycidyl ether include a novolak type epoxy resin which is a glycidyl ester of novolak obtained from a phenol derivative such as phenol, alkylphenol, or halogenated phenol.

Specific examples of the glycidyl ester include diglycidyl phthalate, diglycidyl terephthalate, diglycidyl dimer, and the like.

Further, other epoxy resins having a glycidyl group include triglycidyl isocyanurate.

In the present invention, a curing agent is added to the epoxy resin composition. As a specific example of the curing agent, 4,4'-
Aromatic amines having active hydrogen such as diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine Aliphatic amines having active hydrogens such as bis (aminomethyl) norbornane, bis (4-aminocyclohexyl) methane, dimer acid ester of polyethyleneimine, epoxy compounds, acrylonitrile, phenol and formaldehyde Thiourea and other modified amines obtained by reacting them, dimethylaniline, dimethylbenzylamine, 2,4,6-tris (dimethylaminomethyl) phenol and third compounds having no active hydrogen such as 1-substituted imidazole Amines, dicyandiamide, tetramethylguanidine, carboxylic anhydrides such as hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, adipic hydrazide or naphthalenedicarboxylic hydrazide And polyphenol compounds such as novolak resins, polymercaptans such as esters of thioglycolic acid and polyol, Lewis acid complexes such as boron trifluoride ethylamine complex, and aromatic sulfonium salts.

It is preferable that these curing agents are combined with an appropriate curing aid in order to enhance the curing activity. Specifically, 3-phenyl-1,1-dimethylurea, 3- (3,4-dichlorophenyl) -1,1-dimethylurea (DCMU), and 3- (3-chloro-4-methylphenyl) are added to dicyandiamide. ) -1,1-Dimethylurea, 2,4-bis (3,
Examples include a combination of a urea derivative such as (3-dimethylureido) toluene as a curing aid, and a combination of a carboxylic acid anhydride or a novolak resin with a tertiary amine as a curing aid.

By making the epoxy resin composition as described above, the flexural modulus of the matrix resin in the fiber reinforced plastic member can be at least 3.1.
GPa or more, preferably 3.3 GPa or more. Also, the tensile elongation of the matrix resin can be 8% or more, preferably 10% or more.

In the present invention, the epoxy resin composition comprises:
It is preferable to include one of the following components (A) and (B). By the combination of these components, the performance of the obtained fiber-reinforced plastic member can be further enhanced in cooperation with the above-mentioned characteristics. (A) a compound having one functional group capable of reacting with an epoxy resin or a curing agent in the molecule and one or more amide bonds (B) a polyester polyurethane having an aromatic ring in the molecule In the present invention, the component (A) Is a compound having one functional group capable of reacting with an epoxy resin or a curing agent and one or more amide bonds in the molecule. This compound is blended as a highly polar compound for increasing the adhesiveness.

The amide bond referred to herein means a partial structure comprising a group selected from a carbonyl group, a thiocarbonyl group, a sulfonyl group, and a phosphoryl group, and a nitrogen atom bonded to the carbon by a single bond. A typical compound having an amide bond is a carboxylic acid amide, but may have an amide bond in a part of the ring, or may have a more complex structure such as imide, urethane, urea, or the like.
It may have a structure such as biuret, hydantoin, carboxylic acid hydrazide, hydroxamic acid, semicarbazide, semicarbazone and the like.

The carbonyl oxygen of the amide bond forms a strong hydrogen bond with a hydrogen atom such as a carboxyl group or a hydroxyl group present on the surface of the reinforcing fiber, thereby increasing the adhesiveness.

Further, since the carbonyl group of the amide bond is a strong permanent dipole, an organic dipole is formed on a reinforcing fiber having high polarizability such as carbon fiber, and the adhesive property is improved by an electric attractive force of the dipole-dipole. Enhance.

If the compound having an amide bond does not have a functional group capable of reacting with an epoxy resin or a curing agent in the molecule, the adhesion between the reinforcing fiber and the matrix resin may not be sufficiently exhibited due to phase separation. Although it may act as a plasticizer and significantly reduce heat resistance, when the compound having an amide bond has a functional group capable of reacting with an epoxy resin or a curing agent in the molecule, such a compound is used in the resin composition. With curing, it becomes a part of the matrix resin network, so there is no fear of causing such adverse effects.

It is known that an epoxy resin composition containing a compound having two or more functional groups capable of reacting with an epoxy resin or a curing agent and one or more amide bonds in the molecule is used for a fiber-reinforced plastic member. However, no remarkable improvement in adhesiveness has been confirmed with these known techniques.
However, the epoxy resin composition containing a compound having one functional group and one or more amide bonds capable of reacting with an epoxy resin or a curing agent in the molecule, which the present inventors have found, has a remarkable effect. You.

The reason is that a compound having two or more functional groups capable of reacting with an epoxy resin or a curing agent in a molecule is chemically bonded to an epoxy resin network at two or more places, so that an oxygen atom of an amide bond is not bonded. A compound having one functional group that can react with an epoxy resin or a curing agent in a molecule, while not being sufficiently close to the surface of the reinforcing fiber, is chemically bonded to the epoxy resin network at only one place. The present inventors presume that the degree of freedom is large, and the oxygen atom of the carbonyl group of the amide bond easily contacts the surface of the reinforcing fiber.

Further, the component (A) has an effect of increasing not only the adhesiveness but also the flexural modulus of the matrix resin. This is considered to be because the oxygen of the hydroxyl group and the carbonyl group present in the epoxy resin forms a strong hydrogen bond and restricts the molecular motion.

The functional groups capable of reacting with the epoxy resin include carboxyl groups, phenolic hydroxyl groups, amino groups,
Examples include a secondary amine structure and a mercapto group. Examples of the functional group which can react with the curing agent include an epoxy group, a double bond conjugated to a carbonyl group, and the like. The double bond conjugated with the carbonyl group performs a Michael addition reaction with an amino group or a mercapto group in the curing agent.

Specific examples of the compound having one carboxyl group and having an amide bond include succinamic acid, oxamic acid, N-acetylglycine, N-acetylalanine, 4-acetamidobenzoic acid, N-acetylanthranilic acid, 4-acetamidobutyric acid, 6-acetamidohexanoic acid,
Hippuric acid, 5-hydantoin acetic acid, pyroglutamic acid, 2-
(Phenylcarbamoyloxy) propionic acid and the like.

Specific examples of the compound having one phenolic hydroxyl group and having an amide bond include salicylamide,
4-hydroxybenzamide, 4-hydroxyphenylacetamide, 4-hydroxyacetanilide, 3-hydroxyacetanilide and the like.

Specific examples of the compound having one amino group and having an amide bond include 4-aminobenzamide, 3-aminobenzamide, 4'-aminoacetanilide, 4-aminobutylamide, 6-aminohexanamide, Examples include 3-aminophthalimide, 4-aminophthalimide and the like.

Specific examples of the compound having one secondary amine structure and having an amide bond include nipecotamide, N, N-diethylnipecotamide, isonipecotamide, 1-acetylpiperazine and the like.

Specific examples of the compound having one mercapto group and having an amide bond include 4-acetamidothiophenol, N- (2-mercaptoethyl) acetamide and the like.

Specific examples of the compound having one epoxy group and having an amide bond include glycidamide, N-phenylglycidamide, N, N-diethylglycidamide, N-methoxymethylglycidamide, and N-hydroxymethylglycidamide. Damide, 2,3-epoxy-3-methylbutylamide, 2,3-epoxy-2-methylpropionamide, 9,10-epoxystearamide, N-glycidylphthalimide and the like.

In the compound having one double bond conjugated to a carbonyl group and having an amide bond, the carbonyl group conjugated to the double bond may be the same as or different from the carbonyl group of the amide bond. . Compounds in which the carbonyl group conjugated to the double bond is the same as the carbonyl group of the amide bond include amides of α, β-unsaturated carboxylic acids and derivatives thereof having a substituent on the nitrogen atom. Specific examples of such compounds include acrylamide, methacrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, N-tert-butylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-
Hydroxymethylacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, Nn-
Examples include propoxymethylacrylamide, Nn-butoxymethylacrylamide, N-isobutoxymethylacrylamide, N-benzyloxymethylacrylamide, diacetoneacrylamide, 1-acryloylmorpholine, 1-acryloylpiperidine and the like. In addition, imides of unsaturated dicarboxylic acids such as maleimide, N-ethylmaleimide, and N-phenylmaleimide are also applicable. Examples of the compound in which the carbonyl group conjugated to the double bond is not the same as the carbonyl group of the amide bond include 2- (phenylcarbamoyloxy) ethyl methacrylate.

The component (A) may be used alone or as a mixture of a plurality of types in the epoxy resin composition.

The component (A) (when a plurality of types are used, the total thereof) accounts for 0.5 to 15% by weight, preferably 3 to 15% by weight, based on 100% by weight of the total epoxy resin in the epoxy resin composition. It is good to mix. 0.5% by weight
If the amount is smaller, the effect of improving the adhesiveness is not sufficiently exhibited, and 1
If it is more than 5% by weight, heat resistance may be reduced.

The component (A) may be a liquid or a solid at room temperature. When a solid component is used as the component (A), it may be mixed with the epoxy resin composition and then dissolved by means such as heating and stirring, or may be mixed without being dissolved. When the solid component (A) is blended without dissolving, it is preferable to use the solid component (A) by pulverizing it to a particle size of 10 μm or less.

In the present invention, the component (B) is blended as a compound for increasing the elastic modulus without lowering the tensile elongation of the cured resin.

That is, since the urethane structure present in the molecule of the constituent element (B) forms a strong hydrogen bond with the hydroxyl group present in the epoxy resin and restrains the molecular motion, the elastic modulus of the cured resin is increased. It is estimated that

In the constituent element (B), the ester structure in the molecule reacts with the amino group, mercapto group, phenolic hydroxyl group, etc. in the curing agent by a nucleophilic substitution reaction to form a part of the network of the cured epoxy resin. Therefore, there is also a characteristic that phase separation does not occur and the elastic modulus of the cured resin is hardly reduced.

In the present invention, as the constituent element (B), for example, a polyisocyanate having two or more isocyanate groups in a polyester polyol obtained by polycondensation of a polyhydric carboxylic acid and a polyhydric alcohol, and optionally a chain extension Polyester polyurethane obtained by applying a conventionally known method such as a one-shot method or a prepolymer method using an agent can be used. In the present invention, one or more components (B) can be blended in the resin composition.

Examples of the polycarboxylic acid include malonic acid, succinic acid, succinic anhydride, glutaric acid, adipic acid, azelaic acid, sebacic acid, phthalic acid, phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, and isophthalic acid. Acid, terephthalic acid, nadic acid anhydride, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, etc., among which succinic acid And aliphatic polycarboxylic acids such as adipic acid.

As the polyhydric alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4
-Butylene glycol, 1,5-butylene glycol,
1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol,
Dipropylene glycol, 2,2,4-trimethyl-
1,3-pentanediol, cyclohexanediol,
Bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, glycerin, trimethylolpropane, trimethylolethane, pentaerythritol and the like, among which 1,2-propylene glycol, 1,
4-butylene glycol, 1,6-hexanediol and the like are preferably used.

As the polyisocyanate, an aromatic polyurethane can be used since the synthesized polyurethane has an aromatic ring in the molecule, and the elasticity of the cured product obtained by heating and curing the epoxy resin composition is further increased. Isocyanates are preferably used. For example, 2,4
-Tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, tolidine diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, p-
Phenylene diisocyanate, m-phenylene diisocyanate, xylylene diisocyanate, tetramethyl xylene diisocyanate, triphenylmethane triisocyanate, tris (isocyanate phenyl) thiophosphate, and oligomers thereof, among which 2,4-tolylene diisocyanate, 2,2 6-tolylene diisocyanate and 4,4'-diphenylmethane diisocyanate are preferably used.

As the chain extender, 1,2-propylene glycol, 1,4-butanediol, 1,6-hexanediol, polyethylene glycol, polypropylene glycol, and a mixture thereof are used.

In the present invention, the component (B) is used in an amount of 1 to 15 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the total epoxy resin. If the amount is less than 1 part by weight, the effect of improving the elastic modulus of the cured resin becomes insufficient, and if it exceeds 15 parts by weight, the heat resistance of the cured resin may decrease.

In the present invention, in addition to the components (A) and (B), other components such as a suitable polymer compound and organic or inorganic particles are appropriately added to the epoxy resin composition for the purpose. It can be blended accordingly.

As the polymer compound, a thermoplastic resin is preferably used. By blending the thermoplastic resin, the effect of improving the viscosity of the resin composition and the handleability of the prepreg or improving the adhesiveness is enhanced.

The thermoplastic resin used here is preferably a thermoplastic resin having a hydrogen-bonding functional group which can be expected to have a synergistic effect of improving the adhesiveness which is the object of the present invention.

Examples of the hydrogen bonding functional group include an alcoholic hydroxyl group, an amide bond, and a sulfonyl group.

Examples of the thermoplastic resin having an alcoholic hydroxyl group include polyvinyl acetal resins such as polyvinyl formal and polyvinyl butyral, polyvinyl alcohol, phenoxy resins, and thermoplastic resins having an amide bond include polyamide, polyimide, and thermoplastic resins having a sulfonyl group. Examples of the plastic resin include polysulfone. Polyamide, polyimide and polysulfone may have a functional group such as an ether bond or a carbonyl group in the main chain. The polyamide may have a substituent on the nitrogen atom of the amide group.

Examples of commercially available thermoplastic resins having a hydrogen bonding functional group that are soluble in an epoxy resin include, as polyvinyl acetal resins, denkabutyral and denkaformal (registered trademark, manufactured by Denki Kagaku Kogyo KK), Vinylek (registered trademark, manufactured by Chisso Corporation), UCARPKHP (model number, manufactured by Union Carbide) as a phenoxy resin, Macromelt (registered trademark, manufactured by Henkel Hakusui Corporation) as a polyamide resin, Amilan CM4000
(Registered trademark, manufactured by Toray Industries, Inc.), Ultem (registered trademark, manufactured by General Electric) as polyimide, M
atrimid 5218 (registered trademark, manufactured by Ciba Co., Ltd.), and polysulfone such as Victrex (registered trademark, manufactured by Mitsui Chemicals, Inc.) and UDEL (registered trademark, manufactured by Union Carbide Co., Ltd.).

When a thermoplastic resin is blended, the thermoplastic resin is used as the total epoxy resin 1 in the epoxy resin composition.
It is preferable to mix 1 to 20% by weight with respect to 00% by weight in order to impart appropriate viscoelasticity to the epoxy resin composition and increase the mechanical strength of the resulting fiber-reinforced plastic member.

As the organic particles to be mixed in the epoxy resin composition, rubber particles and thermoplastic resin particles are used.
These particles have the effect of improving the toughness of the resin and the impact resistance of the fiber reinforced plastic member.

Further, as the rubber particles, crosslinked rubber particles and core-shell rubber particles obtained by graft-polymerizing a different polymer on the surface of the crosslinked rubber particles are preferably used.

Commercially available crosslinked rubber particles include XER-91 (model number, manufactured by Nippon Synthetic Rubber Industry Co., Ltd.) composed of a crosslinked product of a carboxyl-modified butadiene-acrylonitrile copolymer, and CX-MN series composed of acrylic rubber fine particles. (Model number, manufactured by Nippon Shokubai Co., Ltd.), YR-500 series (model number, manufactured by Toto Kasei Co., Ltd.) and the like can be used.

Examples of commercially available core-shell rubber particles include paraloid EXL-2655 (registered trademark, manufactured by Kureha Chemical Industry Co., Ltd.) made of butadiene / alkyl methacrylate / styrene copolymer, and acrylate / methacrylate copolymer. Staphyloid AC-335 consisting of
5, TR-2122 (registered trademark, model number, manufactured by Takeda Pharmaceutical Co., Ltd.), PARALOIDEXL-2611, E comprising butyl acrylate / methyl methacrylate copolymer
XL-3387 (registered trademark, model number, manufactured by Rohm & Haas)
Etc. can be used.

As the thermoplastic resin particles, polyamide or polyimide particles are preferably used.
As commercially available polyamide particles, Toray Industries, Ltd.
P-500, manufactured by ATOCHEM, orgasol (registered trademark) or the like can be used.

As the inorganic particles to be blended in the epoxy resin composition, silica, alumina, smectite, synthetic mica and the like can be blended. These inorganic particles are blended into the epoxy resin composition mainly for rheological control, that is, for increasing viscosity and imparting thixotropic properties.

Various known methods are used for producing the fiber-reinforced plastic member of the present invention. For producing sports goods such as golf shafts, fishing rods and rackets, the epoxy resin composition as described above is used. , Making a prepreg by impregnating reinforcing fibers typified by carbon fiber,
It is preferable to adopt a method of laminating, heating and curing to obtain a fiber-reinforced plastic member from the viewpoint of easy handling, convenience in molding, and the like.

The prepreg is produced by a method such as a wet method in which a matrix resin is dissolved in methyl ethyl ketone, methanol and a solvent to reduce the viscosity and impregnated into reinforcing fibers, and a hot melt method in which the viscosity is reduced by heating and impregnated into reinforcing fibers. be able to.

The wet method is a method in which a prepreg is obtained by immersing a reinforcing fiber in a solution composed of a resin composition, then pulling the fiber, and evaporating the solvent while heating using an oven or the like.

The hot melt method is a method of directly impregnating a reinforcing fiber with a resin composition whose viscosity has been reduced by heating, or a method of preparing a film in which the resin composition is once coated on release paper or the like, and then reinforcing the fiber. There is a method in which such a film is overlaid on both sides or one side of the fiber and heated to impregnate the resin composition into a prepreg. The hot melt method is preferred because the solvent does not substantially remain in the prepreg.

The fiber reinforced plastic member can be produced by a conventionally known method in which, after laminating such prepregs, the resin composition is heated and cured while applying pressure to the laminate.

The method of applying heat and pressure includes a press molding method, an autoclave molding method, a bagging molding method, a wrapping tape method, an internal pressure molding method and the like. Particularly, for sports goods, the wrapping tape method and the internal pressure molding method are used. It is preferably adopted.

Further, as a method for obtaining a cylindrical composite material from a prepreg, there is a wrapping tape method. The wrapping tape method can be preferably used when a prepreg is wound around a core metal such as a mandrel to produce a cylindrical body such as a golf shaft or a fishing rod. Specifically, a prepreg is wound around a mandrel, and a wrapping tape made of a thermoplastic resin film is wound around the outside of the prepreg for fixing the prepreg and applying pressure, and after heating and curing the resin in an oven, a core metal is formed. Is a method of extracting a cylindrical composite material.

In the internal pressure forming method, a preform in which a prepreg is wound around an internal pressure applying body such as a tube made of a thermoplastic resin is placed in a mold, and then a high pressure gas is introduced into the internal pressure applying body to reduce the pressure. This is a method of applying and heating the mold to mold. The method includes a golf shaft, a bat,
It can be preferably used when obtaining a molded article having a complicated shape such as a tennis or badminton racket.

[0088]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments. Preparation of each physical property measurement sample and measurement of physical property values were performed by the following methods. Table 1 summarizes the contents of the examples and comparative examples. (1) Preparation of prepreg The resin composition was applied on release paper using a reverse roll coater to prepare a resin film. Next, the two resin films are overlapped so as to be sandwiched from both sides of carbon fibers aligned in one direction in a sheet shape, and heated under pressure to impregnate the carbon fibers with the resin.
A prepreg of 25 g / m ² was obtained. (2) 90 ° bending strength of a fiber reinforced plastic member A unidirectional composite material obtained by laminating 20 unidirectional prepregs was subjected to a temperature of 130 ° C and a pressure of 29 in an autoclave.
The sample was heated and cured at 0 Pa for 2 hours to prepare a test piece having a width of 15 mm, a length of 60 mm, and a thickness of 2 mm so that the 90 ° direction was the longitudinal direction. Using this sample, a bending test was performed according to JIS K7074, and a 90 ° bending strength was measured. The distance between the fulcrums was 40 mm and the crosshead speed was 1 mm / min. (3) by operating the Preparation below the cylindrical composite material (a) ~ (e), has a laminated structure of [0 ₃ / ± 45 _3] with respect to the cylinder axis, an inner diameter of 6.3mm
And 10 mm cylindrical composite materials were produced. As the mandrel, a stainless steel round bar having a diameter of 6.3 mm and 10 mm (both having a length of 1000 mm) was used. (A) The unidirectional prepreg is formed into a rectangular shape of 800 mm long × 68 mm wide for a mandrel having a diameter of 6.3 mm and 800 mm × 103 mm wide for a mandrel having a diameter of 10 mm such that the fiber direction is at 45 degrees to the axial direction of the mandrel. Two pieces were cut out. The two sheets were laminated such that the fiber directions crossed each other and were shifted in the lateral direction by 10 mm for a mandrel having a diameter of 6.3 mm and 16 mm for a mandrel having a diameter of 10 mm (corresponding to a half circumference of the mandrel). (B) The bonded prepreg was wound around a mandrel subjected to a release treatment so that the longitudinal direction of the prepreg coincided with the axial direction of the mandrel. (Bias material) (c) On the prepreg, a mandrel with a diameter of 6.3 mm is 800 mm long so that the fiber direction is vertical.
× 800 mm long with a mandrel of 77 mm wide and 10 mm diameter
A rectangular cutout having a size of 112 mm × 112 mm was wound so that the longitudinal direction of the prepreg coincided with the axial direction of the mandrel. (Straight material) (d) A wrapping tape (heat-resistant film tape) was wrapped around and heated and molded at 130 ° C. for 2 hours in a curing furnace. (E) After molding, the mandrel was pulled out and the wrapping tape was removed to obtain a cylindrical composite material. (4) Measurement of Torsional Strength A test piece having a length of 400 mm was cut out from a cylindrical composite material having an inner diameter of 10 mm, and was referred to as “Grafting Standards for Golf Club Shafts and Standard Confirmation Methods” (ed by the Japan Product Safety Association, approved by the Minister of International Trade and Industry, No. 5, 2087) No. 1993).
A torsion test was performed. The test piece gauge length is 300 mm,
50 mm at both ends of the test piece were gripped by a fixing jig. The torsional strength was determined by the following equation.

Torsion strength (N · m · deg) = breaking torque (N · m)
× Torsion angle at break (deg) (5) Tensile strength and tensile modulus of carbon fiber The carbon fiber to be measured is manufactured by Union Carbide Co., Ltd.
Bakelite (registered trademark) ERL-4221 1000
g (100 parts by weight), a resin composition obtained by mixing 30 g (3 parts by weight) of boron trifluoride monoethylamine (BF ₃ .MEA) and 40 g (4 parts by weight) of acetone,
Next, the mixture was heated at 130 ° C. for 30 minutes and cured to obtain a resin-impregnated strand. Resin-impregnated strand test method (JIS
R7601), the tensile strength and the tensile modulus were determined. (6) Tensile elongation of carbon fiber Measured according to JIS R7601. (7) Amount of functional group on carbon fiber surface Surface specific oxygen concentration O / C Surface specific oxygen concentration O / C was determined by X-ray photoelectron spectroscopy according to the following procedure.

First, the sizing agent and the like were removed from the carbon fiber bundle to be measured with a solvent, cut to an appropriate length, spread on a stainless steel sample support, and measured under the following conditions.

Photoelectron escape angle: 90 degrees X-ray source: MgKα1,2 Vacuum in sample chamber: 1 × 10 ⁻⁸ Torr Next, the main component of C _1S was used to correct peaks caused by charging during measurement. B. Peak binding energy value E. FIG. 284.6 eV
I adjusted to.

Next, the C _1s peak area [C _1s ] is 28
Obtained by drawing a linear base line in the range of 2 to 296 eV, the O _1s peak area [O _1s ] is 528 to 54
It was determined by drawing a straight base line in the range of 0 eV.

The surface specific oxygen concentration O / C was determined by the following equation from the ratio of the O _1s peak area [O _1s ], the C _1s peak area [C _1s ], and the sensitivity correction value unique to the apparatus.

O / C = ([O _1s ] / [C _1s ]) / (sensitivity correction value) Here, as a measuring device, a product of Shimadzu Corporation is used.
Using ESCA-750, the sensitivity correction value unique to the device was set to 2.85. B. Surface carboxyl group concentration COOH / C Surface carboxyl group concentration COOH / C was determined by chemically modified X-ray photoelectron spectroscopy according to the following procedure.

First, a sizing agent or the like is removed from a carbon fiber bundle to be measured with a solvent, cut into a suitable length, spread on a platinum sample support, and then arranged at 0.02 mol / L.
Was exposed to air containing 60% of dicyclohexylcarbodiimide gas and 0.04 mol / L of pyridine gas at 60 ° C. for 8 hours for chemical modification treatment, and then measured under the following conditions.

Photoelectron escape angle: 35 degrees X-ray source: AlKα1,2 Vacuum in sample chamber: 1 × 10 ⁻⁸ Torr Next, the main component of C _{1 S} was used to correct peaks caused by charging during measurement. B. Peak binding energy value E. FIG. 284.6 eV
I adjusted to.

Next, the C _1s peak area [C _1s ] is 28
It is obtained by drawing a linear base line in the range of 2 to 296 eV, and the F _1s peak area [F _1s ] is 682 to 69
It was determined by drawing a straight base line in the range of 5 eV.

Further, as a comparative sample, the reaction rate r was determined by dividing the C _1s peak of chemically modified polyacrylic acid.
And the residual ratio m of the dicyclohexylcarbodiimide derivative was determined from the O _1s peak splitting. Next, the surface carboxyl group concentration COOH / C was determined by the following equation.

COOH / C = [F _1s ] / [(3k [C _1s ]-(2 + 13
m) [F _1s ]) r] = 100 (%) Here, model SSX-100-206 manufactured by SSI, USA was used.
The sensitivity correction value k of the F _1s peak area with respect to the C _1s peak area unique to this apparatus was 3.919. (7) Crystal size Lc of carbon network plane by wide-angle X-ray diffraction Preparation of measurement sample From the cured resin plate prepared in the same manner as in A of the above (1), a test piece of 4 cm in length is cut out and solidified using a mold and a collodion-alcohol solution to form a prism and a measurement sample. did. B. Measurement conditions X-ray source: CuKα (using Ni filter) Output: 40 kV, 20 mA Measurement of crystal size Lc The crystal size Lc was calculated from the half width of the peak of the plane index (002) obtained by the transmission method using the following Scherrer equation. Lc (hkl) = Kλ / β ₀ cos θ _B where Lc (hkl): average size in the direction perpendicular to the (hkl) plane of the microcrystal K: 1.0, λ: wavelength of X-ray, β ₀ : (Β _E2 −β ₁₂ ) _1/2 β _E : apparent half width (measured value), β ₁₂ : 1.05 × 1
0 ^-2 rad. θ _B : Bragg angle (Example 1) The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 35 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 55 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Multifunctional Glycidylamine type epoxy resin 10 parts by weight (Sumi-Epoxy ELM-434, registered trademark, manufactured by Sumitomo Chemical Co., Ltd.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3, 3) 4-dichlorophenyl) -1,1-dimethylurea 3 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) Nn-butoxymethylacrylamide 5 parts by weight (manufactured by Kasano Kosan Co., Ltd.) 7 parts by weight of polyvinyl formal (Vinilec K, registered trademark, manufactured by Chisso Corporation) Using this resin composition, According to the method, the tensile strength in the fiber direction using a carbon fiber 5.5 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Example 2 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 35 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 55 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Multifunctional Glycidylamine type epoxy resin 10 parts by weight (Sumi-Epoxy ELM-434, registered trademark, manufactured by Sumitomo Chemical Co., Ltd.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3, 3) 4-dichlorophenyl) -1,1-dimethylurea 3 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) Nn-butoxymethylacrylamide 5 parts by weight (manufactured by Kasano Kosan Co., Ltd.) 7 parts by weight of polyvinyl formal (Vinilec K, registered trademark, manufactured by Chisso Corporation) Using this resin composition, According to the method, the tensile strength in the fiber direction using a carbon fiber 4.9 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Example 3 The following raw materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 35 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 55 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Multifunctional Glycidylamine type epoxy resin 10 parts by weight (Sumi-Epoxy ELM-434, registered trademark, manufactured by Sumitomo Chemical Co., Ltd.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3, 3) 4 parts by weight of 4-dichlorophenyl) -1,1-dimethylurea (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) 5 parts by weight of Nn-dimethylacrylamide (produced by Kojin Co., Ltd.) 5 parts by weight of polyvinyl formal ( (Vinilec K, registered trademark, manufactured by Chisso Corporation) Using this resin composition, Tensile strength in the fiber direction using a carbon fiber 4.4 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Example 4 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 30 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 40 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Novolak type Epoxy resin 30 parts by weight (Epiclon N-740, registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3,4-dichlorophenyl) ) -1,1-Dimethylurea 4 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) 5 parts by weight of Nn-butoxymethylacrylamide (manufactured by Kasano Kosan Co., Ltd.) 5 parts by weight of polyvinyl formal (VINYLEC K , Registered trademark, manufactured by Chisso Corporation) Using this resin composition, Tensile strength in the fiber direction using a carbon fiber 5.4 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Example 5 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 30 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 30 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Novolak type Epoxy resin 30 parts by weight (Epiclon N-740, registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.) Bisphenol F type epoxy resin 10 parts by weight (Epototo YDF-2001, registered trademark, manufactured by Toto Kasei Co., Ltd.) Dicyandiamide 4 Parts by weight (DICY7, model number, manufactured by Yuka Shell Epoxy Co., Ltd.) 3- (3,4-dichlorophenyl) -1,1-dimethylurea 3 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) N- 5 parts by weight of n-butoxymethylacrylamide (manufactured by Kasano Kosan Co., Ltd.) Lumpur 7 parts by weight (Vinylec K, registered trademark, manufactured by Chisso Corporation) by using the resin composition according to the method described above, the tensile strength in the fiber direction using a carbon fiber 4.9 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Example 6 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 30 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 25 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Novolak type Epoxy resin 45 parts by weight (Epiclon N-740, registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3,4-dichlorophenyl) ) -1,1-Dimethylurea 4 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) N-isopropylacrylamide 5 parts by weight (manufactured by Kojin Co., Ltd.) Polyvinylformal 7 parts by weight (vinylek K, registered trademark) Using the resin composition, the fiber direction was determined according to the method described above. Definitive tensile strength using a carbon fiber of 5.5GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Example 7 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 35 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 55 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Multifunctional Glycidylamine type epoxy resin 10 parts by weight (Sumi-Epoxy ELM-434, registered trademark, manufactured by Sumitomo Chemical Co., Ltd.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3, 3) 4-Dichlorophenyl) -1,1-dimethylurea 3 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) Polyester polyurethane 5 parts by weight ("PANDEX" T-5205, registered trademark, Dainippon Ink Industries, Ltd.) 7 parts by weight of polyvinyl formal (Vinilec K, registered trademark, Chisso Corporation) Ltd.) by using the resin composition according to the method described above, the tensile strength in the fiber direction using a carbon fiber 5.5 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 1 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Comparative Example 1 A resin composition was obtained by mixing the following raw materials with a kneader. Bisphenol A type epoxy resin 35 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 55 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Multifunctional Glycidylamine type epoxy resin 10 parts by weight (Sumi-Epoxy ELM-434, registered trademark, manufactured by Sumitomo Chemical Co., Ltd.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3, 3) 4 parts by weight of 4-dichlorophenyl) -1,1-dimethylurea (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) 7 parts by weight of polyvinyl formal (vinylile K, registered trademark, manufactured by Chisso Corporation) According to the method described above, a carbon fiber having a tensile strength in the fiber direction of 5.5 GPa was used. ,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 2 shows the 90 ° bending strength of the fiber reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Comparative Example 2 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 30 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 30 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Novolak type Epoxy resin 30 parts by weight (Epiclon N-740, registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.) Bisphenol F type epoxy resin 10 parts by weight (Epototo YDF-2001, registered trademark, manufactured by Toto Kasei Co., Ltd.) Dicyandiamide 4 Parts by weight (DICY7, model number, manufactured by Yuka Shell Epoxy Co., Ltd.) 3- (3,4-dichlorophenyl) -1,1-dimethylurea 3 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) Polyvinyl formal 7 parts by weight (Vinilec K, registered trademark, manufactured by Chisso Corporation) This resin With formation thereof, in accordance with the method described above, the tensile strength in the fiber direction using a carbon fiber 4.9 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 2 shows the 90 ° bending strength of the fiber reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg. Comparative Example 3 The following materials were mixed in a kneader to obtain a resin composition. Bisphenol A type epoxy resin 30 parts by weight (Epototo YD-128, registered trademark, manufactured by Toto Kasei Co., Ltd.) Bisphenol A type epoxy resin 40 parts by weight (Epicoat 1001, registered trademark, Yuka Shell Epoxy Co., Ltd.) Novolak type Epoxy resin 30 parts by weight (Epiclon N-740, registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.) Dicyandiamide 5 parts by weight (DICY7, model number, Yuka Shell Epoxy Co., Ltd.) 3- (3,4-dichlorophenyl) ) -1,1-Dimethylurea 4 parts by weight (DCMU99, model number, manufactured by Hodogaya Chemical Industry Co., Ltd.) 5 parts by weight of polyvinyl formal (Vinilec K, registered trademark, manufactured by Chisso Corporation) Using this resin composition, According to the method described above, using a carbon fiber having a tensile strength in the fiber direction of 5.4 GPa,
A prepreg was prepared with a matrix resin content of 24% by weight. Table 2 shows the 90 ° bending strength of the fiber-reinforced plastic member and the torsional strength of the cylindrical composite material obtained by heating and curing this prepreg.

[0100]

[Table 1]

[0101]

[Table 2]

[0102]

According to the present invention, it is possible to provide a fiber-reinforced plastic member which is hard to be broken in a crushing mode, is lightweight, and is excellent in torsional strength, especially when it is made of a cylindrical composite material. it can.

The fiber reinforced plastic member according to the present invention is preferably used in sports applications such as golf shafts, fishing rods, rackets such as tennis, badminton and squash, sticks such as hockey, ski poles and the like due to its excellent mechanical strength. . In aerospace applications, it is preferably used for primary structural materials such as wings, tail fins, and floor beams, secondary structural materials such as flaps, ailerons, cowls, fairings, and interior materials, rocket motor cases, and artificial satellite structural materials. Can be Furthermore, in general industrial applications, structural materials of moving objects such as automobiles, ships, and railway vehicles, drive shafts, leaf springs, windmill blades, pressure vessels, flywheels, papermaking rollers, roofing materials, cables, reinforcing bars, repair reinforcement It is preferably used for civil engineering and building materials such as materials.

Continued on the front page F term (reference) 4F072 AB10 AD23 AD43 AG03 AK02 AK05 AK14 AL04 AL05 4J002 CC042 CD051 CD061 CD111 CD121 CD141 CK033 EL136 EN036 EN046 EN066 EN076 EP017 EQ026 ET006 EU026 EU116 EU186 EV026 EV037 EV226 EY016 FD 146

Claims (10)

[Claims] 1. A fiber reinforced plastic member comprising a reinforcing fiber and a matrix resin obtained by curing an epoxy resin composition containing a curing agent, the fiber reinforced having a 90 ° bending strength of 130 to 180 MPa. Plastic parts. 2. The fiber-reinforced plastic member according to claim 1, wherein the fiber-reinforced plastic member is obtained by heating and curing a prepreg obtained by impregnating a reinforcing fiber with an epoxy resin composition. 3. The fiber-reinforced plastic member according to claim 1, wherein the reinforcing fibers are carbon fibers. 4. The surface carboxyl group concentration C of the carbon fiber measured by a chemically modified X-ray photoelectron spectroscopy.
The fiber reinforced plastic member according to claim 3, wherein OOH / C is 0.002 to 0.03. 5. The carbon fiber according to claim 1, wherein a surface specific oxygen concentration O / C measured by X-ray photoelectron spectroscopy is 0.02 to 2.0.
The fiber reinforced plastic member according to claim 3 or 4, wherein the ratio is 0.3. 6. The method according to claim 1, wherein the epoxy resin composition contains 2
The fiber-reinforced plastic member according to any one of claims 1 to 5, comprising 70 to 100% by weight of the epoxy resin having one epoxy group based on 100% by weight of the total epoxy resin. 7. The fiber-reinforced plastic member according to claim 1, wherein the epoxy resin composition comprises the following component (A). (A) Compound having one functional group and one or more amide bonds capable of reacting with an epoxy resin or a curing agent in a molecule 8. The content of the component (A) is 100% by weight of the total epoxy resin in the epoxy resin composition.
The fiber-reinforced plastic member according to claim 7, wherein the amount is 0.5 to 15% by weight based on the weight of the member. 9. The fiber reinforced plastic member according to claim 1, wherein the epoxy resin composition comprises the following component (B). (B) Polyester polyurethane having an aromatic ring in the molecule 10. The fiber reinforced plastic member according to claim 9, wherein the amount of the component (B) is 1 to 15% by weight based on 100% by weight of the total epoxy resin in the epoxy resin composition.