JP2010189561A - Fiber-reinforced composite material and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber-reinforced composite material resistant to external shock, excellent in fatigue characteristics upon variation of the application environment, for example, change in temperature and repeated load, which is most suitably used for members such as primary structure of airplanes. <P>SOLUTION: This fiber-reinforced composite material includes at least the following constituting elements: [A] a carbon fiber flux comprising 6,000-70,000 filaments; [B] a hardened article of a specified thermosetting resin; [C] a core-shell polymer particle having a volume-average particle diameter of 1-500 nm; and [D] a specified amorphous thermoplastic resin, wherein composite layers 1 which include at least constituting elements [A], [B] and [C], and composite layers 2 which include at least constituting elements [B], [C] and [D] are alternately laminated, and the composite layer 1 has a region which contains substantially no constituting element [D], and the composite layer 2 has an average layer thickness of 10-50 μm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a carbon fiber, a fiber reinforced composite material having a thermosetting resin cured product, and a method for producing the same, and more specifically, carbon having 6,000 to 70,000 filaments. Non-crystalline containing a fiber bundle, a thermosetting resin cured product, a core-shell polymer particle having a volume average particle diameter of 1 to 500 nm, and a bond group selected from an amide group, a sulfonyl group, and an imide group in the molecule. The present invention relates to a fiber-reinforced composite material suitable for structural members such as aircraft members, spacecraft members, automobile members, and ship members, and a manufacturing method thereof.

  Conventionally, fiber-reinforced composite materials made of carbon fiber, glass fiber, and other reinforcing fibers and epoxy resins, phenol resins, and other thermosetting resins are lightweight, yet have mechanical properties such as strength and rigidity, heat resistance, and corrosion resistance. Therefore, it has been applied to many fields such as aircraft, spacecraft, automobiles, railway vehicles, ships, civil engineering, and sports equipment. Especially in applications where high performance is required, fiber reinforced composite materials using continuous reinforcing fibers are used, carbon fibers with excellent specific strength and specific elastic modulus are used as reinforcing fibers, and mechanical properties are used as matrix resins. Many epoxy resins having excellent adhesiveness with carbon fibers are used.

  However, a cured product of a thermosetting resin such as an epoxy resin generally has a lower fracture toughness than a thermoplastic resin. This causes a problem that the impact resistance of the fiber reinforced composite material is lowered. In particular, in the case of aircraft structural members, improvement in impact resistance has been a major issue because excellent impact resistance is required against tool dropping during assembly and impact of a kite during operation.

  The fiber reinforced composite material generally has a laminated structure. When an impact is applied to the fiber reinforced composite material, high stress is generated between the layers, and peeling damage occurs due to the in-plane shear mode (opening mode II).

In order to suppress the peeling damage caused by the in-plane shear mode, it is effective to improve the mode II critical energy release rate (hereinafter sometimes abbreviated as _GIIC ) of the thermosetting resin. In order to improve the impact resistance against external impact, it is only necessary to improve the G _IIC of the resin layer forming the interlayer of the fiber reinforced composite material.

In order to improve the G _IIC of the thermosetting resin, it is effective to increase the plastic deformation ability of the thermosetting resin, and as a means for that, a thermoplastic resin having an excellent plastic deformation ability is blended. .

As a method of blending a thermoplastic resin, various studies have been made in a prepreg method which is one of the methods for forming a fiber-reinforced composite material. For example, there is a method of using, as a matrix resin, a high toughness thermosetting resin obtained by dissolving a thermoplastic resin in a thermosetting resin to increase the toughness (see Patent Documents 1 and 2). However, when the thermoplastic resin is blended with the thermosetting resin, the viscosity is remarkably increased, so that the blending amount of the thermoplastic resin is limited. Therefore, it is difficult to improve the G _{IIC of the} thermosetting resin beyond a certain level.

Therefore, a study has been made to locally add a thermoplastic resin material between the layers of the fiber reinforced composite material. In the prepreg method, a fiber reinforced composite material is laminated and cured by placing a thermoplastic resin on the surface of the prepreg before curing. The G _{IIC of the} thermosetting resin that forms the interlayer of the material has been dramatically improved. Various proposals have been made regarding the form of the thermoplastic resin disposed on the surface of the prepreg (see Patent Documents 3 to 11).

  On the other hand, in addition to impact from the outside, fiber reinforced composite materials have a resin cured product due to internal stress generated by the difference in linear expansion coefficient between the reinforced fiber and the cured product of thermosetting resin and repeated loading (fatigue) of the load. Damage due to the opening mode (opening mode I) may occur. Thereby, a crack may generate | occur | produce inside a fiber reinforced composite material, and problems, such as reducing water resistance and a mechanical physical property, may arise. It should be particularly noted in the occurrence of internal cracks due to internal stress and repeated load, unlike the impact from the outside, damage is generated not only between the layers.

To suppress internal cracks caused by the opening mode, it is effective to improve the mode I critical energy opening of the thermosetting resin (sometimes abbreviated as G _IC.).

As a method for improving the G _IC of the thermosetting resin, there is a method of blending the thermoplastic resin in the thermoset resin, the amount of the thermoplastic resin due to a problem of viscosity increase as described above There is a limit.

  As a means for improving the toughness of a thermosetting resin with a small increase in viscosity, a method for blending polymer particles having a core-shell structure has been proposed in addition to the above-described method for blending a thermoplastic resin (see Patent Documents 12 to 13). .

  However, the expression rate of toughness improvement effect varies depending on the difference in the components that make up the polymer having a core-shell structure.If the selection fails, a large amount of compounding is required to achieve the required toughness. In some cases, there is a problem that even the heat resistance is lowered. Particularly in the case of structural members for aircraft, the use environment reaches a very low temperature range below -50 ° C. Therefore, in order to achieve both toughness development in the cryogenic temperature range and mechanical properties and heat resistance, the polymer having a core-shell structure is used. Ingredient selection becomes very important.

  In recent years, the application has been expanded due to the high potential for reducing molding costs. Resin transfer molding (hereinafter referred to as “resin transfer molding”), in which a reinforced fiber base material is directly impregnated with a liquid thermosetting resin and cured. In the method, the thermosetting resin is injected after laminating a fiber base material made of reinforcing fibers. Therefore, when the thermosetting resin is injected into the reinforcing fiber base material, the thermosetting resin has a low viscosity. There are restrictions on the resin design that it must be liquid, and if the particle diameter of the particles to be blended is not designed well, the particles may be filtered out on the outermost surface of the laminated fiber base material. May impede the thermosetting resin impregnation flow path, resulting in the occurrence of unimpregnated parts, which may reduce the opportunity physical properties of the resulting fiber-reinforced composite material There is also.

As described above, various studies have been conducted in the past to improve the impact resistance of fiber reinforced composite materials. However, fiber reinforced composite materials have been designed to cope with external impacts, internal stresses, and repeated loads. inside reinforced composite material, the G _IC in the layer, rather than the spirit and techniques improve each is independently a G _IIC in layers, it is very to realize a fiber-reinforced composite material, especially manufactured by the RTM method Since these were difficult problems, it was desired to solve these problems.

Japanese Patent Laid-Open No. 62-297314 JP-A 62-297315 European Published Patent No. 366979 European Published Patent No. 495518 JP-A-1-320146 European Patent No. 274899 Specification European Published Patent No. 707032 European Patent No. 488389 JP-A-2-32843 European Patent No. 657492 JP-A-8-48796 JP-A-5-65391 JP 2003-277579 A

  In view of the background of such prior art, the object of the present invention is a fiber-reinforced composite material that is resistant to external impacts, and further excellent in fatigue characteristics such as changes in the use environment, specifically temperature changes and repeated loads. An object of the present invention is to provide a fiber reinforced composite material that is molded by a resin transfer molding method and is optimal for a member such as an aircraft primary structure.

The present invention employs the following means in order to solve such problems. That is, a fiber-reinforced composite material composed of at least the following components [A], [B], [C] and [D], comprising at least the components [A], [B] and [C]. The composed composite layer 1 and the composite layer 2 composed of at least the constituent elements [B], [C] and [D] are alternately formed, and the composite layer 1 includes the constituent element [D]. The fiber-reinforced composite material is characterized in that there is no region and the average layer thickness of the composite layer 2 is 10 to 50 μm.
[A] a carbon fiber bundle having 6,000 to 70,000 filaments,
[B] A cured product obtained by curing a thermosetting resin composition containing at least the following components [B-1] and [B-2],
[B-1] Thermosetting resin containing at least one selected from epoxy resin, cyanate resin, bismaleimide resin, benzoxazine resin,
[B-2] a component capable of curing the component [B-1],
[C] Core-shell polymer particles having a volume average particle diameter of 1 to 500 nm,
[D] An amorphous thermoplastic resin containing one or more linking groups selected from amide groups, sulfonyl groups, and imide groups in the molecule.

  According to a preferred aspect of the fiber-reinforced composite material of the present invention, in the composite layer 1, the component [D] is not contained in an inner region of 20 μm or more from the outer periphery of the component [A], and the composite layer The component [C] content in the component [B] constituting 2 is less than the component [C] content in the component [B] constituting the composite layer 1.

  Further, according to a preferred aspect of the fiber-reinforced composite material of the present invention, the constituent element [A] is a warp made of a carbon fiber bundle and an auxiliary warp of a fiber bundle made of glass fiber or chemical fiber arranged in parallel therewith. And wefts of fiber bundles made of glass fibers or chemical fibers arranged orthogonally to them, and the auxiliary warp yarns and the weft yarns cross each other to hold the carbon fiber bundles together to form a woven fabric More preferably, the fineness of the auxiliary warp of the fiber bundle made of glass fiber or chemical fiber is 20% or less of the fineness of the warp made of carbon fiber bundle. The fineness of the weft of the fiber bundle made of glass fiber or chemical fiber is 10% or less of the fineness of the warp made of the carbon fiber bundle.

  The component [B] is a cured product obtained by heat-curing an epoxy resin composition in which the component [B-1] is an epoxy resin and the component [B-2] is an aromatic polyamine. In the element [C], the core component is preferably crosslinked polybutadiene, and the glass transition temperature of the core component is preferably −40 ° C. or lower.

The fiber-reinforced composite material of the present invention provides a composition having a form selected from a fibrous form, a sheet form, and a particulate form containing the constituent element [D] on at least one surface of the sheet-like article containing the constituent element [A]. The fiber substrate is placed in a mold, impregnated by injecting the component [E], and then heated and cured, so-called resin transfer molding (RTM).
[A] a carbon fiber bundle having 6,000 to 70,000 filaments,
[E] Thermosetting that includes at least the following components [B-1], [B-2] and [C], and has a viscosity of not more than 300 mPa · s within 5 minutes from the start of measurement at a temperature of 70 ° C. Resin composition,
[B-1] Thermosetting resin containing at least one selected from epoxy resin, cyanate resin, bismaleimide resin, benzoxazine resin,
[B-2] a component capable of curing the component [B-1],
[C] Core-shell polymer particles having a volume average particle diameter of 1 to 500 nm,
[D] An amorphous thermoplastic resin containing in the molecule at least one linking group selected from an amide group, a sulfonyl group, and an imide group.

  According to the preferable aspect of the manufacturing method of the fiber reinforced composite material of this invention, component [E] consists of the main ingredient which consists of at least component [B-1] and [C], and at least component [B-2]. It is a two-pack type epoxy resin composition comprised from the hardening | curing agent which becomes, and includes the process of mixing this main ingredient and this hardening | curing agent.

  Moreover, according to the preferable aspect of the manufacturing method of the fiber reinforced composite material of this invention, as this component [D], a glass transition temperature is 150 degreeC or more, and a component [B- 1] or having a functional group capable of reacting with [B-2].

  Moreover, according to the preferable aspect of the manufacturing method of the fiber reinforced composite material of this invention, the sheet-like material containing carbon fiber consists of the warp which consists of a carbon fiber bundle, and the glass fiber or chemical fiber arranged in parallel with this. The auxiliary warp of the fiber bundle and the weft of the fiber bundle made of glass fiber or chemical fiber arranged so as to be orthogonal thereto, and the carbon fiber bundle is integrally held by the auxiliary warp and the weft intersecting each other A non-crimped woven fabric in which a woven fabric is formed, the fibrous base material is placed between a rigid open mold and a flexible film, Vacuum evacuates between flexible films, injects and impregnates resin mixture, and heat cures, so-called vacuum assist resin transfer molding More preferably, the fineness of the auxiliary warp of the fiber bundle made of glass fiber or chemical fiber of the fiber base material forming the non-crimp fabric is 20 times the fineness of the warp made of carbon fiber bundle. % And the fineness of the weft of the fiber bundle made of glass fiber or chemical fiber is 10% or less of the fineness of the warp made of carbon fiber bundle.

  Furthermore, according to the preferable aspect of the manufacturing method of the fiber reinforced composite material of this invention, after inject | pouring the resin mixture containing component [B] and component [C], it heats up to the arbitrary temperature of the range of 50-140 degreeC. The primary curing is performed, and then the secondary curing is performed by raising the temperature to an arbitrary temperature in the range of 160 to 180 ° C.

  The fiber-reinforced composite material of the present invention has excellent impact resistance against external impact, high post-impact compressive strength (CAI), and high resistance to fatigue. It is excellent and can be suitably used for structural members such as aircraft members, spacecraft members, automobile members, and ship members.

The fiber-reinforced composite material of the present invention is composed of at least the following components [A], [B], [C] and [D].
[A] a carbon fiber bundle having 6,000 to 70,000 filaments,
[B] A cured product obtained by curing a thermosetting resin composition containing at least the following components [B-1] and [B-2],
[B-1] Thermosetting resin containing at least one selected from epoxy resin, cyanate resin, bismaleimide resin, benzoxazine resin,
[B-2] a component capable of curing the component [B-1],
[C] Core-shell polymer particles having a volume average particle diameter of 1 to 500 nm,
[D] An amorphous thermoplastic resin containing in the molecule at least one linking group selected from an amide group, a sulfonyl group, and an imide group.

  The carbon fiber constituting the carbon fiber bundle which is the constituent element [A] used in the fiber-reinforced composite material of the present invention specifically includes carbon fibers such as acrylic, pitch and rayon, and particularly tensile. High-strength acrylic carbon fibers are preferably used. As the form of the carbon fiber, twisted yarn, untwisted yarn, untwisted yarn and the like can be used, but untwisted yarn or untwisted yarn is preferably used because the balance between moldability and strength characteristics of the fiber reinforced composite material is good.

  The tensile elastic modulus of the carbon fiber is preferably in the range of 200 GPa to 400 GPa from the viewpoint of the characteristics and weight of the molded structural member. If the elastic modulus is lower than this range, the rigidity of the structural member may be insufficient and weight reduction may be insufficient. Conversely, if the elastic modulus is higher than this range, the strength of the carbon fiber generally tends to decrease. A more preferable elastic modulus is in the range of 250 GPa to 370 GPa, and more preferably in the range of 290 GPa to 350 GPa. Here, the tensile elastic modulus of the carbon fiber is measured according to JIS R7601-2006.

  In the present invention, the carbon fiber bundle of the component [A] is used as a sheet-like fiber base material. The sheet-like fiber base material is composed of carbon fibers alone or in combination with other inorganic fibers and chemical fibers, and the forms thereof include those in which the fiber directions are aligned substantially in the same direction, woven fabrics, knits, braids and A mat or the like can be used, but the carbon fibers are substantially oriented in one direction, particularly in that a fiber reinforced composite material having high mechanical properties and a high volume content of reinforcing fibers is obtained. So-called unidirectional fabrics fixed with fibers or chemical fibers are preferably used.

  As a unidirectional woven fabric, for example, carbon fiber bundles are arranged parallel to each other in one direction as warp yarns, and weft yarns of fiber bundles made of glass fibers or chemical fibers intersecting with each other to form a plain weave structure Or a warp made of a carbon fiber bundle and an auxiliary warp of a fiber bundle made of glass fiber or chemical fiber having a fineness smaller than that of the carbon fiber arranged in parallel to this, and glass fiber or chemical fiber arranged so as to be orthogonal to these For example, a non-crimp woven fabric in which a carbon fiber bundle is integrally held and a woven fabric is formed by the auxiliary warp and the weft intersecting each other.

  Here, the fineness refers to a weight per 1000 m of fiber bundle (hereinafter referred to as tex). In the present invention, the carbon fiber bundle is composed of 6,000 to 70,000 filaments, and the fineness is preferably in the range of 400 to 5,000 tex, more preferably composed of 12,000 to 25,000 filaments, The fineness is 800 to 1,800 tex. If the number and fineness of the carbon fiber filaments are smaller than the range, there are too many crossing points in the woven fabric and the mechanical properties may decrease. Conversely, if the number and fineness of the carbon fiber filaments are larger than the ranges, the crossing in the woven fabric may occur. Since there are too few points and the form stability of a textile fabric and handleability may fall, it is not preferable.

  In the case of a woven fabric having a plain weave structure, the carbon fiber bundle is bent because the carbon fiber bundle and the weft are orthogonal to each other. Since the auxiliary warp is more easily deformed than the carbon fiber bundle, the carbon fiber bundle is difficult to bend. The fineness of the fiber bundle of glass fiber or chemical fiber forming the auxiliary warp is preferably 20% or less, more preferably 10% or less. By setting the fineness of the auxiliary warp to 20% or less of the fineness of the carbon fiber bundle, the auxiliary warp is more easily deformed than the carbon fiber bundle, and a woven fabric can be formed without bending the carbon fiber bundle. The lower limit of the fineness of the auxiliary warp is not particularly limited. The smaller the better, the better. However, in terms of the form stability and production stability of the fabric, it is generally 0.05% or more.

  In addition, if the fineness of the weft forming the woven structure is too large, bending of the carbon fiber bundle may be promoted. Therefore, the fineness of the fiber bundle of glass fiber or chemical fiber forming the weft is preferably 10% or less, more preferably 5% or less. There is no particular lower limit on the fineness of the weft yarn. The lower the better, the better, but it is generally 0.05% or more from the viewpoint of the form stability and production stability of the fabric.

  When the carbon fiber bundle is bent, there is a possibility of unevenness in volume distribution occupied by the carbon fiber in the fiber bundle, and contact between the single fibers of the carbon fiber may occur. When the contact between the single fibers of carbon fiber occurs, the portion is not impregnated with the thermosetting resin, which becomes a defect and may deteriorate adhesiveness and mechanical properties. Therefore, the fiber base material which comprises the textile fabric of the non-crimp structure where a carbon fiber bundle is hard to bend can be used especially preferable.

  The cured product obtained by curing the thermosetting resin composition, which is the component [B] used in the fiber-reinforced composite material of the present invention, is obtained by heat-curing the thermosetting resin composition.

  Specifically, as the constituent element [B-1] constituting the constituent element [B], an epoxy resin, a cyanate resin, a bismaleimide resin, and a benzoxazine resin are preferably used. Of these, the epoxy resin is most preferable in terms of a balance between price and performance, and a wide range of commercially available raw materials and a high degree of design freedom.

  Here, in the present invention, the epoxy resin refers to a compound having two or more epoxy groups in one molecule. The epoxy resin composition is an epoxy resin, a component for curing the epoxy resin (generally referred to as a curing agent, a curing catalyst, or a curing accelerator), and a modifier (plasticizer, Dye, organic pigment and inorganic filler, polymer compound, antioxidant, UV absorber, coupling agent, surfactant, etc.) It refers to a high molecular weight polymer that has been polymerized until the epoxy resin composition is heated to undergo a crosslinking reaction and has a glass transition temperature of at least 50 ° C. or higher.

  In the present invention, examples of the epoxy resin constituting the constituent element [B-1] include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, tetrabromobisphenol A diglycidyl ether, bisphenol AD diglycidyl ether, and 2,2. ', 6,6'-tetramethyl-4,4'-biphenol diglycidyl ether, N, N, O-triglycidyl-m-aminophenol, N, N, O-triglycidyl-p-aminophenol, N, N, O-triglycidyl-4-amino-3-methylphenol, N, N-diglycidylaniline, N, N-diglycidyl-o-toluidine, N, N, N ′, N′-tetraglycidyl-4,4 '-Methylenedianiline, N, N, N', N'-tetraglycidyl-2,2'-di Tyl-4,4′-methylenedianiline, N, N, N ′, N′-tetraglycidyl-m-xylylenediamine, 1,3-bis (diglycidylaminomethyl) cyclohexane, ethylene glycol diglycidyl ether, propylene Glycol diglycidyl ether, hexamethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, diglycidyl phthalate, diglycidyl terephthalate, vinylcyclohexene diepoxide, 3, 4-epoxycyclohexanecarboxylic acid-3,4-epoxycyclohexylmethyl, bis-3,4-epoxycyclohexylmethyl adipate, 1,6-dihydro Diglycidyl ether of sinaphthalene, diglycidyl ether of 9,9-bis (4-hydroxyphenyl) fluorene, triglycidyl ether of tris (p-hydroxyphenyl) methane, tetraglycidyl ether of tetrakis (p-hydroxyphenyl) ethane, Phenol novolac glycidyl ether, cresol novolac glycidyl ether, glycidyl ether of condensate of phenol and dicyclopentadiene, glycidyl ether of phenol aralkyl resin, triglycidyl isocyanurate, N-glycidyl phthalimide, 5-ethyl-1,3-diglycidyl-5 -Obtained by addition of methylhydantoin, 1,3-diglycidyl-5,5-dimethylhydantoin, bisphenol A diglycidyl ether and tolylene isocyanate Such as oxazolidone type epoxy resins and the like.

  In particular, N, N, N ′, N′-tetraglycidyl-4,4′-methylenedianiline, which is a polyfunctional epoxy resin, has a high effect of improving heat resistance and is excellent in chemical resistance of a cured product. N, N, O-triglycidyl-p-aminophenol is preferably used because it has a very low viscosity among epoxy resins having an effect of improving heat resistance and has an effect of reducing the viscosity of the epoxy resin composition. it can. Such an epoxy resin is preferably 40 to 85 parts by weight, more preferably 45 to 75 parts by weight, based on 100 parts by weight of the total epoxy resin. By setting the amount of the epoxy resin to 40 parts by weight or more in 100 parts by weight of the total epoxy resin, the glass transition temperature of the resulting cured product, and thus the fiber-reinforced composite material containing the cured epoxy resin can be increased. In addition, when the epoxy resin is 85 parts by weight or less with respect to 100 parts by weight of the total epoxy resin, it is possible to suppress a decrease in fracture toughness of the cured epoxy resin and to be suitable for a fiber-reinforced composite material.

  In addition to the epoxy resin, N, N-diglycidylaniline and N, N-diglycidyl-o-toluidine having a diglycidylaniline skeleton have a low viscosity, reducing the free volume in the cured resin and increasing the elastic modulus. Since the improvement effect is high, it can be preferably used. The epoxy resin is preferably 10 to 55 parts by weight, more preferably 15 to 50 parts by weight, based on 100 parts by weight of the total epoxy resin. By setting the blending amount of the epoxy resin to 10 parts or more in 100 parts by weight of the total epoxy resin, the viscosity of the resulting epoxy resin composition is lowered, and the elastic modulus of the cured product obtained by heat curing is increased. The compression characteristics of the fiber reinforced composite material containing the cured resin can be improved. Further, when the epoxy resin is 55 parts by weight or less with respect to 100 parts by weight of the total epoxy resin, the heat resistance and fracture toughness of the cured resin are obtained. This is suitable for fiber-reinforced composite materials.

  In the present invention, as the constituent element [B-2] constituting the constituent element [B], an amine compound, a phenol compound, a polyol compound, an acid anhydride, or the like is appropriately selected depending on the components used in the constituent element [B-1]. In particular, when an epoxy resin is used as the constituent element [B-1], aliphatic polyamine, aromatic polyamine, dicyandiamide, polycarboxylic acid, polycarboxylic acid hydrazide, acid anhydride, polymercaptan, polyphenol A compound that performs a stoichiometric reaction and a compound that acts catalytically, such as imidazole, Lewis acid complex, and onium salt, can be used as a curing agent. When a compound that undergoes a stoichiometric reaction is used, a curing accelerator such as imidazole, Lewis acid complex, onium salt, phosphine, and the like may be blended. When molding fiber-reinforced composite materials by RTM molding, aliphatic polyamines, aromatic polyamines, acid anhydrides, and imidazoles are suitable, and aromatics are particularly desirable for the production of structural materials with excellent heat resistance. Polyamines are most suitable.

  When a fiber reinforced composite material is molded by RTM molding, a liquid one is used among aromatic polyamines. Examples of the liquid aromatic polyamine include diethyltoluenediamine (a mixture containing 2,4-diethyl-6-methyl-m-phenylenediamine and 4,6-diethyl-2-methyl-m-phenylenediamine as main components), 2,2'-diethyl-4,4'-methylenedianiline, 2,2'-isopropyl-6,6'-dimethyl-4,4'-methylenedianiline, 2,2 ', 6,6' tetraisopropyl Examples thereof include alkyl group derivatives of diaminodiphenylmethane such as -4,4'-methylenedianiline and polyoxytetramethylene bis (p-aminobenzoate). Of these, diethyltoluenediamine having a low viscosity and excellent physical properties as a cured product such as a glass transition temperature can be preferably used.

  A solid aromatic polyamine can be blended with the liquid aromatic polyamine to such an extent that crystals do not precipitate. As solid aromatic polyamines, 3,3′-diaminodiphenyl sulfone and 4,4′-diaminodiphenyl sulfone can provide a cured product having excellent heat resistance and elastic modulus, and further, thermal expansion is reduced due to linear expansion coefficient and moisture absorption. Can be used preferably. In general, diaminodiphenyl sulfone has a strong crystallinity, and even if it is mixed with liquid aromatic polyamine at a high temperature to form a liquid, it tends to precipitate as a crystal in the cooling process. However, two isomers of diaminodiphenyl sulfone and liquid aromatic polyamine are used. When they are mixed, it is preferable because precipitation of crystals can be suppressed much more than the mixture of a single diaminodiphenyl sulfone and a liquid aromatic polyamine, and the amount of diaminodiphenyl sulfone can be increased. The amount of diaminodiphenyl sulfone is preferably 10 to 40 parts by weight, more preferably 20 to 35 parts by weight, per 100 parts by weight of the wholly aromatic amine. If the blending amount is 10 parts by weight or more, the effect of the cured product as described above can be easily obtained, and if the blending amount is 40 parts by weight or less, the precipitation of crystals is easily suppressed. When 3,3′-diaminodiphenylsulfone and 4,4′-diaminodiphenylsulfone are used in combination in order to suppress the precipitation of crystals, the weight ratio of both is preferably 10:90 to 90:10, The closer the ratio between the two, the higher the effect of suppressing crystal precipitation.

  In the present invention, when an epoxy resin is used as the component [B-1] and a polyamine curing agent is used as the component [B-2], the compounding amount of the epoxy resin and the curing agent is one epoxy group of all epoxy resins. On the other hand, the amount of active hydrogen in the curing agent is preferably in the range of 0.7 to 1.3, more preferably 0.8 to 1.2. Active hydrogen refers to a highly reactive hydrogen atom bonded to nitrogen, oxygen, or sulfur in an organic compound. When the ratio between the epoxy group and the active hydrogen is out of the above range, the heat resistance and elastic modulus of the obtained resin cured product may be lowered.

  In the present invention, when an aromatic polyamine is used as the constituent element [B-2], the aromatic polyamine is generally known to have a slow crosslinking reaction. Therefore, a curing accelerator is used to accelerate the reaction. Can be blended. As a hardening accelerator, hardening accelerators, such as a tertiary amine, a Lewis acid complex, onium salt, an imidazole, a phenol compound, can be mix | blended, for example.

  When a fiber reinforced composite material is produced by RTM molding, it is preferable that the shape is small enough to allow the carbon fiber bundle to be impregnated with a uniform concentration of the curing accelerator. Specifically, the volume average particle diameter is 0.5 μm or less, more preferably 0.1 μm or less, and most preferably the liquid aromatic polyamine is completely dissolved until no solid content exists. By satisfying the above requirements, a fiber-reinforced composite material exhibiting stable mechanical properties can be obtained. Here, the completely dissolved state means a liquid material that dissolves and does not have a solid component and has no concentration distribution, and even when the liquid material is stored at 25 ° C. for one month or longer. Means that it is kept in a state where no precipitation occurs.

  When a fiber reinforced composite material is produced by RTM molding, an increase in viscosity during resin injection must be suppressed. t-Butyl catechol is preferably used because it is suitable for the RTM method because it has a characteristic that the reaction promoting effect is small at the temperature (50 to 80 ° C.) at the time of resin injection, and the promoting effect increases in a temperature range of 100 ° C. it can.

  When the curing accelerator is blended with the curing agent, the blending amount is preferably 0.5 to 3 parts by weight, more preferably 1 to 2.5 parts by weight based on 100 parts by weight of the total epoxy resin. is there. If the blending amount of the curing accelerator is out of this range, the balance between the uncured handling time and the reaction rate at high temperature is lost, which is not preferable.

  The core-shell polymer particles, which are the constituent element [C] used in the fiber-reinforced composite material of the present invention, are different from the core component on the surface of the particulate core component mainly composed of a crosslinked rubber-like polymer or elastomer. By graft polymerization of the component polymer, a part or the whole of the surface of the particulate core component is coated with the shell component, and the fracture toughness of the cured product can be greatly improved by adding a small amount.

  As the core component constituting the core-shell polymer, a polymer polymerized from one or more selected from conjugated diene monomers, acrylic acid and / or methacrylic acid ester monomers, or a silicone resin can be used.

  When the fiber reinforced composite material is used for structural members, particularly aircraft applications, high heat resistance is required. When an epoxy resin composition is used as the thermosetting resin, the cured product is amorphous and has a glass transition temperature. Under a temperature atmosphere equal to or higher than the glass transition temperature, the cured epoxy resin significantly decreases in rigidity, and accordingly, the mechanical properties of the fiber-reinforced composite material also decrease. Therefore, the glass transition temperature of the cured epoxy resin is used as an index of heat resistance of the fiber reinforced composite material. The glass transition temperature of the cured epoxy resin correlates with the highest temperature in the thermal history of the curing process. For aircraft applications, the maximum temperature of the curing process is often selected at about 180 ° C. Therefore, in the step of producing a fiber-reinforced composite material, the glass transition temperature of the cured product finally cured by heating at 180 ° C. for 2 hours is preferably 180 ° C. or higher, and more preferably 190 ° C. or higher. However, the thermal decomposition temperature of the epoxy resin is said to be about 240 ° C. regardless of uncured and cured states, and the upper limit of the glass transition temperature is substantially equal to or lower than the thermal decomposition temperature.

On the other hand, fiber reinforced composite materials used for aircraft applications are exposed to a very low temperature atmosphere of −50 ° C. or lower, particularly for aircraft flying at high altitudes. For this reason, the environmental fatigue from the glass transition temperature to the extremely low temperature described above accumulates in the fiber reinforced composite material, and when mechanical fatigue due to repeated loading is added, the fiber reinforced composite material has an opening mode (crack opening) in the resin cured product. Cracks due to mode I) may occur. If further environmental fatigue and repeated load are applied while the crack is generated, the crack grows more and may ultimately degrade the mechanical properties of the fiber-reinforced composite material. In order to prevent cracking caused by environmental fatigue and repetitive load (abbreviated as G _IC.) Mode I critical energy opening of the resin cured product is effective to enhance the, is G _IC especially at Cryogenic Temperatures Become important. Therefore, a crosslinked rubber composed of a conjugated diene monomer having a glass transition temperature of the core component of −30 ° C. or lower, preferably −40 ° C. or lower is optimal. When it is difficult to measure the glass transition temperature of the core component after it is converted into a core-shell polymer, a polymer is prepared using only the core component, and the glass transition temperature of the obtained polymer is measured in advance by a thermal analysis instrument such as DSC. It may be measured.

  Examples of the conjugated diene monomer include butadiene, isoprene, chloroprene and the like, and the core component used is preferably a crosslinked rubber constituted by using these alone or in combination. It is particularly preferable to use butadiene as the conjugated diene monomer, that is, to use a crosslinked polybutadiene as the core component because the properties of the obtained polymer are good and the polymerization is easy.

  The shell component that constitutes the core-shell polymer is preferably graft-polymerized to the above-described core component, and is preferably chemically bonded to the polymer that constitutes the core component. The component constituting the shell component is, for example, a polymer polymerized from one or more selected from (meth) acrylic acid esters, aromatic vinyl compounds and the like.

  The shell component preferably has a functional group that reacts with the epoxy resin composition of the present invention in order to stabilize the dispersion state. Examples of such functional groups include a hydroxyl group, a carboxyl group, and an epoxy group.

  The average particle diameter of the core-shell polymer used in the present invention is preferably 1 to 500 nm in terms of volume average particle diameter, more preferably 3 to 300 nm. The volume average particle diameter can be measured using a nanotrack particle size distribution measuring apparatus (manufactured by Nikkiso Co., Ltd., dynamic light scattering method). When the volume average particle diameter of the core-shell polymer used in the present invention is 1 nm or less, it is difficult to produce and cannot be used substantially. When the volume average particle diameter is 500 nm or more, the fiber-reinforced composite material is used in the molding process. In the step of injecting and impregnating the epoxy resin composition, it is not preferable because it is separated by reinforcing fibers and the dispersed state in the fiber-reinforced composite material may become uneven.

  There is no restriction | limiting in particular in the manufacturing method of the core-shell polymer used by this invention, The thing manufactured by the well-known method can be used. However, the core-shell polymer is usually handled as a powder by pulverizing what is taken out as a lump, and the powder-like core-shell polymer is often dispersed again in the epoxy resin. It is difficult to disperse stably. Therefore, it is preferable that the core-shell polymer can be handled in the form of a masterbatch that is finally dispersed in the epoxy resin without being taken out in a lump from the production process of the core-shell polymer. For example, JP-A-2004-315572 Obtained by obtaining a suspension in which the core-shell polymer is dispersed by polymerizing by the method described in the publication, that is, by polymerizing the core-shell polymer in an aqueous medium represented by emulsion polymerization, dispersion polymerization, and suspension polymerization. The suspension is mixed with water and an organic solvent that is partially soluble, for example, an ether solvent such as acetone or methyl ethyl ketone, and then brought into contact with a water-soluble electrolyte such as sodium chloride or potassium chloride. After separating the water layer, the epoxy resin is mixed with the core-shell polymer-dispersed organic solvent obtained by separating and removing the aqueous layer. And a method for evaporating and removing the medium can be used. As a core-shell polymer-dispersed epoxy masterbatch dispersed with primary particles in an epoxy resin, “Kane Ace (registered trademark)” commercially available from Kaneka Corporation can be suitably used.

  The thermoplastic resin as the constituent element [D] used in the fiber-reinforced composite material of the present invention is an amorphous thermoplastic resin, and preferably has a glass transition temperature of 150 ° C. or higher, more preferably 160 ° C. That's it. The amorphous thermoplastic resin does not have a crystal structure in the molecule, and therefore does not show a melting point and shows a glass transition temperature.

Moreover, the thermoplastic resin which is the constituent element [D] used in the fiber-reinforced composite material of the present invention contains one or more linking groups selected from amide groups, sulfonyl groups and imide groups in the molecule. The component [D] can react with the component [B-1] or [B-2] at the end or side chain of the molecular structure in the process of heat-curing before forming the fiber-reinforced composite material. It preferably has a functional group such as a hydroxyl group, a carboxyl group, an amino group, or an amide group. Since the component [D] has such a structure before molding, in the fiber-reinforced composite material after molding, the component [D] is combined with the thermosetting resin cured product of the component [B]. Since the interfacial bond strength between B] and [D] is improved, the mode II critical energy release rate between layers (hereinafter abbreviated as _GIIC ) is further improved, and the effect of suppressing the propagation of interlayer cracks is enhanced.

  As such a thermoplastic resin, resins belonging to so-called engineering plastics such as polyimide, polyetherimide, polyethersulfone, grillamide, polyamideimide, polyetherethersulfone and the like are preferably used. Particularly, hydroxyl-terminated polyethersulfone and grillamide are heat resistant. It can be preferably used because of its excellent properties and chemical resistance.

  The form of the thermoplastic resin as the constituent element [D] used in the fiber-reinforced composite material of the present invention is not particularly limited, and particles, fibers, films, porous membranes, knits, nonwoven fabrics, woven fabrics, etc. can be used. Since the form is excellent in the drapability of the fiber base material, it can be preferably used.

  The fiber-reinforced composite material of the present invention is composed of a composite layer 1 composed of at least constituent elements [A], [B] and [C] and at least constituent elements [B], [C] and [D]. The composite layers 2 to be formed are alternately formed. However, each layer does not necessarily need to be uniformly distributed throughout the fiber-reinforced composite material, and there may be a portion where a partially non-uniform portion or layer is missing.

  The composite layer 1 of the fiber-reinforced composite material of the present invention is characterized in that there is a region that does not substantially contain the component [D]. More preferably, the component [D] is not included in an inner region of 20 μm or more from the outer periphery of the carbon fiber bundle that is the component [A] constituting the composite layer 1.

The thermoplastic resin which is the constituent element [D] of the present invention is used for improving impact resistance against external impact. In order to improve the impact resistance, the fiber reinforced composite material does not include carbon fibers between the layers containing carbon fibers. In the present invention, the mode II critical energy release rate (G _{IIC) of the} composite layer 2 is used. ) Is important, and G _IIC inside the carbon fiber layer hardly contributes to the improvement of impact resistance.

  It is known that the viscosity of a thermoplastic resin significantly increases when dissolved in an epoxy resin. In particular, in the case of a thermoplastic resin containing at least one linking group selected from an amide group, a sulfonyl group, and an imide group in the molecule, the increase in viscosity is very large or does not dissolve in the epoxy resin. Therefore, in molding the fiber-reinforced composite material of the present invention, the constituent element [D] is arranged in advance on at least one side of the fiber base material, and after thermosetting resin is injected and impregnated by RTM molding, thermosetting is performed. In this case, the constituent element [D] is intensively arranged on the composite layer 2 and the impact resistance is improved.

  In addition, the constituent element [D] is disposed only in the composite layer 2 because the amount of the thermoplastic resin used is larger than that in the case where the entire fiber-reinforced composite material is toughened with the thermoplastic resin to improve the impact resistance. There is an advantage of less.

  The distribution of the thermoplastic resin as the constituent element [D] in the obtained fiber reinforced composite material is determined by a method of analyzing the reflected electron image on the surface of the fiber reinforced composite material using a scanning electron microscope (SEM) or flying. It can be confirmed by a method of analyzing by mapping elements on the surface of the fiber reinforced composite material by time-type secondary ion mass spectrometry (TOF-SIMS).

In the fiber reinforced composite material of the present invention, in order to have impact resistance against external impact, the average layer thickness of the composite layer 2 is required to be 10 to 50 μm, and preferably 15 to 30 μm. When the average layer thickness of the composite layer 2 is less than 10 μm, the plastic deformation region of the thermoplastic resin as the component [D] is not sufficiently secured, and the G _IIC between the layers is not improved, so that the compressive strength after impact does not appear. When the average layer thickness exceeds 50 μm, the volume fraction of the reinforcing fiber of the composite layer containing the reinforcing fiber becomes too high, and the strength may be lowered due to the influence of stress concentration. Here, the average layer thickness is determined by observing a cross section of the polished fiber-reinforced composite material with a stereoscopic fluorescence microscope system (manufactured by Keyence Co., Ltd.) and calculating on analysis software. Specifically, when the section of the polished fiber reinforced composite material is irradiated with UV excitation light and observed in a fluorescence mode with a stereoscopic fluorescence microscope system equipped with an absorption filter (BFP: excitation wavelength 387/28 nm, absorption wavelength 430 nm) The resin component in the interlayer part is observed in blue. After binarization with analysis software, only the interlayer part is extracted and the area is calculated. The value obtained by dividing the obtained area by the number of composite layers 2 in the fiber-reinforced composite material in the observation range is defined as the average layer thickness.

The fiber-reinforced composite material of the present invention is blended with the core-shell polymer particles of the component [C] in order to improve the mode I critical energy release rate (G _IC ) of the thermosetting resin and improve the fatigue resistance.

Unlike the impact from the outside, the crack generated by fatigue is characterized by occurring in other than the interlayer. However, the composite layer 1 in which a carbon fiber and a thermosetting resin having a large difference in elastic modulus and linear expansion coefficient are mixed is often a source of cracks. Further, since the composite layer 2 is preferentially blended with the thermoplastic resin of the component [D], not only G _IIC but also G _IC is improved to some extent. Thus, it may be intensively performed composite layer 1 to improve the G _IC by the core shell polymer particles of the components [C].

  In the fiber reinforced composite material of the present invention, the composite layer 2 is preferably designed so that the thermoplastic resin as the constituent element [D] is preferentially blended as described above, and the constituent element [D] does not diffuse even during molding. . In this case, even if the thermosetting resin containing the core-shell polymer particles as the constituent element [C] is impregnated, the core-shell polymer particles are reduced in the composite layer 2 by the amount of the thermoplastic resin as the constituent element [D]. That is, the content of the constituent element [C] in the constituent element [B] constituting the composite layer 2 is less than the constituent element [C] content in the constituent element [B] constituting the composite layer 1. Can be said to be preferable. In addition, the [C] content described here means the number of core-shell polymer particles.

  The distribution of the core-shell polymer particles as the constituent element [C] in the obtained fiber-reinforced composite material is determined by using a focused ion beam (FIB) apparatus after dyeing the core-shell polymer particles on the surface of the fiber-reinforced composite material with osmium dyeing. It can be confirmed by making a thin film and observing with a transmission electron microscope (TEM) and comparing the number of core-shell polymer particles per unit area in the composite layers 1 and 2.

  Various methods such as hand lay-up method, hot melt impregnated prepreg method, wet impregnated prepreg method, resin transfer molding (RTM) method can be used as a method for producing fiber reinforced composite materials. In the present invention, the RTM method that can obtain a fiber-reinforced composite material having a high reduction potential and a relatively high quality can be preferably used in the present invention.

When the fiber-reinforced composite material of the present invention is produced by the RTM method, at least one surface of the sheet-like material containing the constituent element [A] is selected from a fibrous form containing the constituent element [D], a sheet form, and a particulate form. A fiber base material to which a composition having a form is applied is placed in a mold, impregnated with component [E], and then cured by heating.
[A] a carbon fiber bundle having 6,000 to 70,000 filaments,
[E] Thermosetting that includes at least the following components [B-1], [B-2] and [C], and has a viscosity of not more than 300 mPa · s within 5 minutes from the start of measurement at a temperature of 70 ° C. Resin composition,
[B-1] Thermosetting resin containing at least one selected from epoxy resin, cyanate resin, bismaleimide resin, benzoxazine resin,
[B-2] a component capable of curing the component [B-1],
[C] Core-shell polymer particles having a volume average particle diameter of 1 to 500 nm,
[D] An amorphous thermoplastic resin containing in the molecule at least one linking group selected from an amide group, a sulfonyl group, and an imide group.

  In the case of the RTM method, after laminating a fiber base material, which is a component [A] alone or a plurality of carbon fibers, and further combined with other chemical fibers as necessary, the component [E] is injected and impregnated. The thermoplastic resin as the component [D] needs to be attached in advance to at least one surface of the fiber substrate in an unimpregnated state.

  As a method for adhering and fixing the thermoplastic resin as the constituent element [D] on the fiber base material, a solution in which the thermoplastic resin is dissolved in an organic solvent is sprayed on the fiber base material and then dried to dry the organic solvent. There is a way to remove.

  However, since this method uses a large amount of organic solvent, the working environment becomes worse. Therefore, a separate organic solvent recovery device is required, which increases the equipment cost.

  There is also a method of arranging particles, fibers, films, porous membranes, knits, woven fabrics, etc., obtained by appropriately processing thermoplastic resins on a fiber substrate, and melting and fixing the thermoplastic resin by heating, but as described above, the present invention Since the thermoplastic resin, which is the component [D] used in the above, has a melting point or glass transition temperature of 150 ° C. or higher, a temperature of 200 ° C. or higher is required for melting until it exhibits fluidity that can be fixed to the fiber substrate. Become. If the carbon fiber constituting the constituent element [A] is treated at such a high temperature, the sizing agent of the carbon fiber may be thermally decomposed and the adhesiveness may be lowered, which is not preferable.

  Therefore, when the fiber-reinforced composite material of the present invention is produced by the RTM method, the thermoplastic resin as the component [D] is adjusted to an appropriate glass transition temperature by blending a plasticizer, and a binder composition having a spacer effect. It is effective to use a thing (sometimes called a tackifier). Specifically, the glass transition temperature is preferably 40 to 100 ° C, more preferably 50 to 80 ° C. If the glass transition temperature is lower than 40 ° C., the layer thickness of the fiber reinforced composite material cannot be maintained easily and easily because it softens immediately during molding. If the glass transition temperature is higher than 100 ° C., the glass transition temperature is high when fusing to the fiber substrate. Is not preferable because it is necessary.

Moreover, when setting it as a binder composition, 50-95 weight part is preferable in 100 weight part of binder compositions, and, as for the compounding quantity of the thermoplastic resin which is component [D], More preferably, it is 55-85 weight part. When the blending amount of the thermoplastic resin as the component [D] is less than 50 parts by weight, a large amount of binder composition is required to obtain an appropriate G _IIC in the composite layer 2 in the obtained fiber-reinforced composite material. Thus, the average layer thickness of the composite layer 2 may become too thick, and the strength may decrease. On the other hand, when the amount is more than 95 parts by weight, the glass transition temperature of the obtained binder composition may be increased.

  Here, as the plasticizer component, it is preferable to select a compound that can react with the constituent element [B-1] or [B-2]. As such a plasticizer component, an epoxy resin is particularly preferable. The epoxy resin used as the plasticizer component is not particularly limited. Specific examples include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, tetrabromobisphenol A diglycidyl ether, bisphenol AD diglycidyl ether, 2,2 ′, 6, 6′-tetramethyl-4,4′-biphenol diglycidyl ether, N, N, O-triglycidyl-m-aminophenol, N, N, O-triglycidyl-p-aminophenol, N, N, O— Triglycidyl-4-amino-3-methylphenol, N, N-diglycidylaniline, N, N-diglycidyl-o-toluidine, N, N, N ′, N′-tetraglycidyl-4,4′-methylenedi Aniline, N, N, N ′, N′-tetraglycidyl-2,2′-diechi -4,4'-methylenedianiline, N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (diglycidylaminomethyl) cyclohexane, ethylene glycol diglycidyl ether, propylene glycol Diglycidyl ether, hexamethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, diglycidyl phthalate, diglycidyl terephthalate, vinylcyclohexene diepoxide, 3, 4 -Epoxycyclohexanecarboxylic acid-3,4-epoxycyclohexylmethyl, bis-3,4-epoxycyclohexylmethyl adipate, 1,6-dihydroxy Diglycidyl ether of naphthalene, diglycidyl ether of 9,9-bis (4-hydroxyphenyl) fluorene, triglycidyl ether of tris (p-hydroxyphenyl) methane, tetraglycidyl ether of tetrakis (p-hydroxyphenyl) ethane, phenol Novolak glycidyl ether, cresol novolak glycidyl ether, glycidyl ether of a condensation product of phenol and dicyclopentadiene, triglycidyl isocyanurate, N-glycidyl phthalimide, 5-ethyl-1,3-diglycidyl-5-methylhydantoin, 1,3- Oxazolidone-type epoxy resin and phenol obtained by addition of diglycidyl-5,5-dimethylhydantoin, bisphenol A diglycidyl ether and tolylene isocyanate Or the like can be mentioned Ruararukiru type epoxy.

  As the plasticizer component, polyphenol, polyamine, polycarboxylic acid, polycarboxylic acid anhydride, polyacrylate, sulfonamide and the like are preferably used other than the epoxy resin.

  For example, examples of the polyphenol include 4-tert-butylcatechol, 2,5-di-tert-butylhydroquinone, bisphenol obtained by condensation of one molecule of limonene and two molecules of phenol.

  An example of the polyamine is diethyltoluenediamine.

  An example of the polycarboxylic acid is 5-tert-butylisophthalic acid.

  Examples of the polycarboxylic acid anhydride include methyl phthalic acid anhydride, methyl hexahydrophthalic acid anhydride, and nadic acid anhydride.

  An example of the polyacrylate is tris (2-acryloyloxyethyl) isocyanurate.

  Examples of the sulfonamide include benzenesulfonamide and toluenesulfonamide.

  Such reactive plasticizers can be used in combination of a plurality of types. In that case, it is necessary to select a similar compound, for example, an epoxy resin, a combination that does not react with each other, or an epoxy resin and a polyacrylate. Combinations that react easily such as epoxy resins and polyamines are not preferred because the reaction proceeds and the glass transition temperature of the binder rises when stored for a long period of time, making it unusable as a binder.

  The preparation of the binder composition using the thermoplastic resin which is the component [D] of the present invention is not particularly limited because it is thermally stable, and various known methods can be used. The most economical method is a method of kneading each component at a relatively high temperature of about 150 to 220 ° C. using an extruder, a kneader or the like. The obtained binder composition can be pulverized into particles, or processed into a fiber or film form by melt extrusion from a die.

  The obtained binder composition is placed on a fiber base material and heat-sealed to prevent dropping. The temperature at this time is preferably 60 to 200 ° C, more preferably 80 to 180 ° C. When the heating temperature is lower than 60 ° C., the binder composition is not sufficiently fused to the fiber substrate, and when it is higher than 200 ° C., the carbon fiber sizing agent may be thermally decomposed, which is not preferable.

  The fiber-reinforced composite material of the present invention can be produced by the RTM method by using a single or a plurality of carbon fibers of the component [A] fused with the above-mentioned binder composition, and, if necessary, other chemical fibers. In particular, a fiber base material combined with the above-described fiber base material, particularly preferably a warp composed of the component [A] and an auxiliary warp of a fiber bundle composed of glass fibers or chemical fibers arranged in parallel to the warp, are arranged so as to be orthogonal thereto. A fiber formed of a non-crimped woven fabric comprising a weft made of glass fiber or chemical fiber, and the auxiliary warp and the weft intersecting each other to form a woven fabric in which carbon fiber bundles are integrally held The component [E] is preferably injected into a preform formed by laminating a predetermined number of substrates at an arbitrary temperature in the range of 40 to 90 ° C. Here, as described above, the fineness of the auxiliary warp of the fiber bundle made of glass fiber or chemical fiber constituting the non-crimp fabric is preferably 20% or less, more preferably 10%. % Or less.

Moreover, it is preferable that the fusion amount of a binder composition is 1-50 g / m < ² > in a fabric weight, More preferably, it is 5-40 g / m < ² >. If the amount of fusion is less than 1 g / m ^{2, the} G _IIC required for the composite layer 2 in the obtained fiber-reinforced composite material cannot be obtained, and if it exceeds 50 g / m ² , the average layer thickness of the composite layer 2 becomes thick. On the contrary, the strength may decrease.

  A specific method for producing a preform is to cut out a fiber base material fused with the above-described binder composition into a predetermined shape, laminate it on a mold, and produce a preform by applying appropriate heat and pressure. Can be used for The pressurizing means can be a press, or a method of bagging and sucking the inside to −90 kPa or less with a vacuum pump and pressurizing with atmospheric pressure. The heating temperature for producing the preform is preferably 60 to 150 ° C. When the heating temperature is 60 ° C. or lower, the layers forming the preform may not be sufficiently fixed. When the heating temperature is 150 ° C. or higher, the binder composition is too crushed to block the flow path of the thermosetting resin. In some fiber reinforced composite materials, unimpregnated portions may occur.

  The mold used in the RTM method may be a closed mold made of a rigid body, or may be a rigid open mold and a flexible film (bag). In the latter case, the fiber substrate can be placed between the rigid open mold and the flexible film.

  As the rigid material, various kinds of existing materials such as metals such as steel and aluminum, fiber reinforced plastic (FRP), wood and gypsum are used. Nylon, fluorine resin, silicone resin, or the like is used as the material for the flexible film.

  When a rigid closed mold is used, it is usually performed by pressurizing and clamping and injecting the mixture under pressure. At this time, it is also possible to provide a suction port separately from the injection port and connect it to a vacuum pump for suction. It is also possible to inject the mixture only at atmospheric pressure without performing a suction and using a special pressurizing means. In this case, the degree of vacuum is preferably reduced to -90 kPa or less. When the degree of vacuum is −90 kPa or more, voids are generated in the fiber-reinforced composite material obtained, and the mechanical properties may deteriorate.

  In the case of using a rigid open mold and a flexible film, suction and injection by atmospheric pressure are usually used. In this case, the degree of vacuum is preferably reduced to -90 kPa or less. When the degree of vacuum is −90 kPa or more, voids are generated in the fiber-reinforced composite material obtained, and the mechanical properties may deteriorate. In order to achieve good impregnation by injection at atmospheric pressure, it is effective to use a resin diffusion medium. Furthermore, it is also preferable to apply a gel coat to the rigid surface prior to installation of the fiber substrate or preform.

  After the installation of the fiber substrate or preform is completed, mold clamping or bagging is performed, and subsequently, the component [E] is injected.

In the present invention, the core-shell polymer particles that are the constituent element [C] are used in combination with the constituent element [B-1] in advance. Moreover, you may mix | blend with component [B-2]. When using an epoxy resin composition as component [B-1], the amount of the core-shell polymer particles blended is 0.5 to 10 parts by weight in 100 parts by weight of the total epoxy resin in component [B-1]. It is preferable to mix 1 to 8 parts by weight. If the amount is 0.5 parts by weight or more, G _IC easily obtained that are required for fiber-reinforced composite material after molding, further, if the amount is less than 10 parts by weight, the elasticity of the cured resin The reduction in rate can be suppressed and the reduction in compression properties of the resulting fiber-reinforced composite material can be minimized.

  The epoxy resin composition generally contains a one-component type that contains a curing agent that is a component capable of curing the epoxy resin and the epoxy resin in advance, and stores the epoxy resin and the curing agent separately, both of which are used immediately before use. There are two-pack types that use a mixture of the two.

  In the case of a one-pack type epoxy resin composition, since the curing reaction proceeds during storage, the curing agent component has low reactivity and is often selected in a solid form. However, since the curing reaction proceeds little by little at room temperature, it is necessary to store in a frozen state, which increases management costs. In addition, since a solid curing agent is used, in order to impregnate the reinforcing fiber with the one-pack type epoxy resin composition, it is necessary to use a press roll and press it at a high pressure, which increases the manufacturing cost.

  On the other hand, since the two-pack type epoxy resin composition stores the main agent and the curing agent composed of the epoxy resin separately, it can be stored for a long time without any particular limitation on the storage conditions. In addition, by making both the main agent and the curing agent liquid, a mixture obtained by mixing the main agent and the curing agent can also be made into a low-viscosity liquid. It can be carried out.

  The epoxy resin composition of the present invention is not particularly limited to a one-pack type or a two-pack type, but a two-pack type is recommended because of the advantages described above.

  In the present invention, when the component [E] is a two-component type, it is preferable to use a mixture of the components [B-1] and [C] as the main agent and the component [B-2] as the curing agent. .

  In the present invention, when the component [E] is a two-component type, the viscosity of the main agent is 300 mPa · s or less at 70 ° C., and the preferred viscosity is 200 mPa · s or less. The viscosity was measured in accordance with JIS Z8803 (1991) "Viscosity measurement method using a cone-plate rotary viscometer" and an E-type viscometer equipped with a standard cone rotor (1 ° 34 '× R24) (Tokimec Co., Ltd.). Using a TVE-30H, manufactured at a rotational speed of 50 rpm. When the viscosity at 70 ° C. is higher than 300 mPa · s, workability such as taking out from the container, weighing, mixing with a curing agent, or degassing treatment may be deteriorated. In order to make the viscosity of the main agent at 70 ° C. not more than 300 mPa · s, the epoxy resin having a molecular weight of 500 or more is preferably 30 parts by weight or more in 100 parts by weight of the total epoxy resin in the component [B-1]. It is not blended and 15 parts by weight or more of the particulate additive such as component [C] is not blended. The lower limit of the viscosity of the main agent at 70 ° C. is not particularly limited, and the lower the viscosity, the easier the injection impregnation of the epoxy resin composition in the RTM method is preferable.

  Moreover, when making component [E] of this invention into a two-component type, the viscosity of a hardening | curing agent is 300 mPa * s or less in 70 degreeC, and a preferable viscosity is 200 mPa * s or less. In addition, the measurement of a viscosity is the same as the measuring method of the main ingredient viscosity mentioned above. When the viscosity at 70 ° C. of the curing agent is higher than 300 mPa · s, workability such as taking out from the container, weighing, mixing with the main agent, or degassing treatment may be deteriorated. The lower limit of the viscosity at 70 ° C. is not particularly limited, and the lower the viscosity, the easier the injection impregnation of the epoxy resin composition in the RTM method is preferable. In order to reduce the viscosity of the curing agent at 70 ° C. to 300 mPa · s or less, as described above, in the component [B-2] used in the present invention, the blending amount of the solid component such as diaminodiphenylsulfone This means that 40 parts by weight or more is not blended in 100 parts by weight of the aromatic polyamine, and 15 parts by weight or more of the particulate additive such as component [C] is not blended.

  Furthermore, the viscosity within 5 minutes from the start of the measurement of the component [E] of the present invention is preferably 300 mPa · s or less at 70 ° C., and more preferably 200 mPa · s or less. In addition, the measurement of a viscosity is the same as the measuring method of the main ingredient and hardening | curing agent viscosity which were mentioned above. When the viscosity within 5 minutes from the start of measurement is higher than the above range, the impregnation property of the component [E] may be insufficient. The lower limit of the viscosity at 70 ° C. is not particularly limited, and the lower the viscosity, the easier the impregnation of the component [E] in the RTM method.

  When the component [E] of the present invention is a two-component type, it is preferable to mix the main agent and the curing agent 2 hours before the injection operation, preferably 1 hour before. After mixing, if necessary, vacuuming is performed with a decompression device until the degree of vacuum becomes −90 kPa or less to remove bubbles mixed in the process of mixing the main agent and the curing agent, oxygen and volatile impurities previously dissolved in the components. A process may suit.

  If the reactivity of the component [E] is high at the injection temperature, the viscosity may increase in the step of removing the bubbles and dissolved impurities and the injection step, which may make molding difficult. Therefore, the time for the viscosity of the constituent element [E] to reach 1000 mPa · s at a temperature of 70 ° C. is preferably 60 minutes or more, and more preferably 90 minutes or more. There is no upper limit on the time to reach 1000 mPa · s at a temperature of 70 ° C., and the longer the time, the better the moldability of the fiber-reinforced composite material. The reactivity of the present invention is controlled by appropriately selecting the components used in the component [B-2] or by defining the blending amount of the curing accelerator blended in the component [B-2].

  After the component [E] is injected and impregnated, heat curing is performed at an arbitrary temperature in the range of 50 to 200 ° C. for an arbitrary time in the range of 0.5 to 10 hours. The heating condition may be one stage or may be a multistage condition in which a plurality of heating conditions are combined. The higher the curing temperature, the higher the heat resistance of the fiber reinforced composite material. However, the higher the heating temperature in the mold during molding, the higher the cost of equipment and heat source, and the longer the occupation time of the mold, the more economical Sexuality gets worse. Also, when heated to a high temperature and cured at once, the component [D] softens quickly or dissolves in the component [E] and penetrates into the component [A] constituting the composite layer 1, The content of the component [D] in 1 may be reduced, and the obtained fiber-reinforced composite material may be vulnerable to external impact. Furthermore, when the component [D] dissolves in the component [E] and penetrates into the component [A] constituting the composite layer 1, the distribution of the component [C] in the fiber-reinforced composite material is uniform. As a result, the content necessary for the composite layer 1 cannot be maintained, and the fatigue characteristics may be deteriorated. Therefore, initial curing is performed at an arbitrary temperature in the range of 50 to 140 ° C., particularly at a temperature in the vicinity of 130 ° C., and then the molded product is removed from the mold, and final curing is performed at a relatively high temperature using an apparatus such as an oven. It is preferable.

  When a structural member for aircraft is assumed, the final curing condition is, for example, a desired resin cured product can be obtained by curing at an arbitrary temperature in the range of 160 to 180 ° C. for 1 to 10 hours. .

  In addition, component [B-1] and [B-2] which comprise component [E] are hardened | cured on the above-mentioned hardening conditions, and the component [the component which is a component of the fiber reinforced composite material of this invention [ B].

  In the fiber-reinforced composite material of the present invention, the volume content of reinforcing fibers is preferably 50 to 65%, and the volume content is more preferably 53 to 60%. When the volume content is less than the above range, the weight of the fiber-reinforced composite material becomes heavy, and the strength tends to decrease due to the influence of stress concentration. Further, when the volume content of the reinforcing fiber is larger than the above range, a defect portion such as an unimpregnated portion or a void is very often generated inside the fiber reinforced composite material, which may cause deterioration in physical properties.

  The fiber-reinforced composite material of the present invention is excellent in impact resistance against external impact, and particularly has high post-impact compressive strength (CAI).

  In order to use the fiber-reinforced composite material of the present invention as an aircraft structural member, the CAI is preferably 200 MPa or more, more preferably 230 MPa or more. The CAI measurement of the fiber reinforced composite material is performed according to JIS K 7089 (1996). If the CAI is lower than 200 MPa, the laminate thickness becomes thick for use as a structural member, and the weight increases accordingly. An increase in weight is not preferable because the fuel efficiency of the aircraft deteriorates.

Moreover, since the fiber reinforced composite material of this invention has the high tolerance with respect to fatigue, it is excellent in the perforated board compressive strength after fixed fatigue provision. Specifically, the fiber reinforced composite material having a thickness of 1 to 3 mm obtained from the cross-laminated preform is measured in the longitudinal direction of the perforated plate test piece measured under the condition of 23 ° C. according to ASTM D6484. maximum load 150 MPa, minimum load 15 MPa, stress ratio R = 10, the sine wave of frequency 5 Hz, preferably perforated plates compressive strength after application 10 ⁶ times the specimen repeating constant load compression load is greater than or equal to 210MPa More preferably, it is 240 MPa or more. When the perforated plate compressive strength after giving a constant fatigue is lower than 210 MPa, it is not preferable because the laminate thickness becomes thick for use as a structural member, and the weight increases accordingly. The upper limit is not particularly set for the perforated plate compressive strength after imparting constant fatigue, but when it is 300 MPa or more, for example, when trying to achieve the volume content control of the reinforcing fiber, the volume content of the reinforcing fiber of the carbon fiber composite material is At least 65% or more is required, so that a very large number of defective portions such as unimpregnated portions and voids are generated inside the fiber reinforced composite material, which may cause deterioration of physical properties.

  The fiber-reinforced composite material of the present invention is light because the volume content of carbon fiber is high, and has excellent resistance to external impacts and changes in environmental temperature and fatigue due to repeated loading, so the fuselage, main wing, tail wing Aircraft members such as moving blades, fairings, cowls, doors, seats and interior materials, spacecraft members such as motor cases and main wings, satellite members such as structures and antennas, outer panels, chassis, aerodynamic members and seats, etc. It can be suitably used for many structural materials such as automobile members, railway vehicle members such as structures and seats, and ship members such as hulls and seats.

  Hereinafter, the present invention will be described more specifically with reference to examples. The unit “part” of the composition ratio means part by weight unless otherwise specified.

<Resin viscosity measurement>
In the thermosetting resin compositions obtained in the examples, the viscosity of the main agent, the curing agent, and the mixture obtained by mixing the main component constituting the thermosetting resin composition is “cone-plate rotation” in JIS Z8803 (1991). According to “viscosity measurement method with viscometer”, using an E-type viscometer equipped with a standard cone rotor (1 ° 34 ′ × R24) (TVE-30H, manufactured by Tokimec Co., Ltd.) at a rotation speed of 50 revolutions / minute The viscosity at a predetermined temperature was measured. In addition, the measured value measured within 5 minutes after mixing a main ingredient and a hardening | curing agent was made into the initial stage viscosity.

<Measurement method of fracture toughness of the cured resin (G _IC)>
The mixture obtained by mixing the main component and the curing agent of the thermosetting resin composition obtained in the examples is poured into a predetermined mold, and is 1.5 ° C. per minute from room temperature to 130 ° C. in a hot air oven. After raising the temperature, hold at 130 ° C. for 2 hours, then raise the temperature to 180 ° C. by 1.5 ° C. per minute, then hold at 180 ° C. for 2 hours and 6 mm thick resin A cured plate was produced. The obtained cured resin plate, after processing the specimen shape described in ASTM D5045-99, was G _IC test according ASTM D5045-99.

<Method for measuring glass transition temperature of cured resin>
The midpoint glass transition temperature was calculated | required by DSC method for the small piece (5-10 mg) of the obtained resin hardening board according to JISK7121-1987. A Pyris 1 DSC (manufactured by Perkin Elmer) was used as a measuring apparatus, and measurement was performed at a temperature rising rate of 40 ° C./min in a nitrogen gas atmosphere.

<Method for measuring interlayer thickness of fiber reinforced composite material>
Stereofluorescence microscope system VB-6000 / 6010 (manufactured by Keyence Corporation) equipped with an absorption filter (BFP: excitation wavelength 387/28 nm, absorption wavelength 430 nm) irradiated with UV excitation light on the cross section of the polished fiber reinforced composite material In the fluorescence mode, the resin component in the interlayer portion is observed in blue. After binarization with analysis software VH Analyzer (manufactured by Keyence Co., Ltd.), only the interlayer portion is extracted and the area is calculated. The value obtained by dividing the obtained area by the number of composite layers 2 in the fiber-reinforced composite material in the observation range was defined as the average layer thickness.

<Distribution measurement of thermoplastic resin in fiber reinforced composite material>
A 6 × 6 × 6 mm piece was cut out from the obtained pseudo-isotropic, 24-layer laminated fiber reinforced composite material, the cross-sectional portion was polished, and then subjected to osmium staining in a draft at a temperature of 25 ° C. for 24 hours.

  Using a field emission scanning electron microscope (FE-SEM) JSM-6340F (manufactured by JEOL Ltd.), the cross-sectional portion of the obtained small piece was measured at an acceleration voltage of 20.0 kV and a magnification of 1000 times. Observations were made at each of three locations in the composite layers 1 and 2.

In the reflected electron composition image of the obtained FE-SEM, the bright part and the dark part are clearly separated by layers, and the cross-sectional part of the small piece used in the FE-SEM is re-sectioned with a microtome for the bright and dark part. Time-of-flight secondary ion mass spectrometer TOF. Using SIMS5 (manufactured by ION-TOF), primary ion Bi ₃ ⁺⁺ , primary ion energy 25 kV, pulse width 100 ns, secondary ion polarity; measured in negative, derived from thermoplastic resin in bright part Negative secondary ions were observed. Therefore, the bright part of the reflected electron composition image of FE-SEM was a part containing a thermoplastic resin, and the dark part was a part not containing a thermoplastic resin.

<Distribution measurement of core-shell polymer particles in fiber-reinforced composite material>
A 6 × 6 × 6 mm piece was cut out from the obtained pseudo-isotropic, 24-layer laminated fiber reinforced composite material, the cross-sectional portion was polished, and then subjected to osmium staining in a draft at a temperature of 25 ° C. for 24 hours.

  The osmium-stained piece is processed into a thin piece with a focused ion beam processing observation apparatus (FIB) Strata400S (manufactured by FEI Company) and observed with a transmission electron microscope (TEM) H-9000UHRII (manufactured by Hitachi High-Technologies Corporation). Went.

  The observation range was 3 × 3 μm, and each of the composite layers 1 and 2 was observed at three locations, and the number of core-shell polymer particles was compared.

<Measurement of compressive strength after impact (CAI) of fiber reinforced composite material>
From the obtained pseudo-isotropic, 24-layer laminated fiber reinforced composite material, a longitudinal test piece having a longitudinal direction of carbon fiber having an orientation angle of 0 degrees and a rectangular test piece having a length of 150 mm and a width of 100 mm was cut out, and the center of the rectangular test piece was After applying a falling weight impact of 20 J per 1 mm thickness of the test piece according to JIS K 7089 (1996), the residual compressive strength (CAI) was measured according to JIS K 7089 (1996). The number of samples was 5.

<Perforated plate compression test method after imparting constant fatigue of fiber reinforced composite material>
From the obtained pseudo-isotropic, 16-layer laminated fiber reinforced composite material, a rectangular test piece of 305 mm length and 38.1 mm width was cut out with the longitudinal direction of the test piece as the carbon fiber orientation angle of 0 degree, and the test piece was subjected to ASTM D6484. A hole with a diameter of 6.35 mm was perforated using a drill and a reamer.

The obtained perforated plate test piece was repeatedly determined by a sine wave having a maximum load of 150 MPa, a minimum load of 15 MPa, a stress ratio R = 10, and a frequency of 5 Hz in the longitudinal direction of the test piece by an MTS810 fatigue tester (manufactured by MTS). It granted 10 ⁶ times the load compressive load to the test piece.
A perforated plate compression test was performed on the obtained constant fatigue imparted perforated plate test piece in accordance with ASTM D6484 at a test speed of 1.27 mm / min. The strength obtained by this test will be referred to as a perforated plate compressive strength (abbreviated as OHC fatigue strength) after imparting constant fatigue.

<Example 1>
"Manufacture of fiber substrate"
As component [A], carbon fiber bundle “Torayca (registered trademark)” T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity The unidirectional sheet-like reinforcing fiber bundle group was formed by drawing at a density of 1.8 fibers / cm with a warp of 294 GPa). Glass fiber E-glass yarn ECE-225-1 / 0-1.0Z (manufactured by Nittobo Co., Ltd., number of filaments: 200, fineness: 22.5 tex) is used as the weft, and the unidirectional sheet-like reinforcing fiber is used. A fiber having a plain weave structure in which the warps and the wefts are woven so as to intersect each other by using a loom, and the carbon fibers are substantially arranged in one direction. The base material 1 was produced. In addition, the fineness ratio of the weft to the warp fineness is 2.2%.

"Manufacture of fiber substrate with binder"
As component [D], hydroxyl-terminated polyethersulfone “SUMICA EXCEL (registered trademark)” 5003P (manufactured by Sumitomo Chemical Co., Ltd.) 60 parts, and bisphenol A type epoxy resin “EPON (registered trademark)” 825 as a plasticizer. 4 parts (manufactured by Japan Epoxy Resin Co., Ltd.), 4 parts of bisphenol F type epoxy resin “jER (registered trademark)” 806 (manufactured by Japan Epoxy Resin Co., Ltd.), N, N, O-triglycidyl-p-aminophenol "JER (registered trademark)" 630 (Japan Epoxy Resin Co., Ltd.) 14 parts, biphenyl aralkyl type epoxy resin NC-3000 (Nihon Kayaku Co., Ltd.) 10 parts and hexahydrophthalic acid diglycidyl ester AK-601 8 parts (manufactured by Nippon Kayaku Co., Ltd.) were melt-kneaded at 210 ° C. with a twin screw extruder, and the resulting composition was cooled. And classified after pulverization, to obtain a volume average particle diameter of 92 [mu] m, the binder particles 1 having a glass transition temperature of 45 ° C.. The volume average particle diameter is measured according to JIS K5600-9-3 (2006) using a laser diffraction / scattering type particle size distribution analyzer (LMS-24, manufactured by Seishin Enterprise Co., Ltd.), and the glass transition temperature is It measured similarly to the measuring method of the glass transition temperature of an above described resin cured material.

The obtained binder particles 1 are spontaneously dropped onto one surface of the fiber substrate 1 while being measured with an embossing roll and a doctor blade, and uniformly dispersed through a vibration net, whereby the binder basis weight becomes 27 g / m ^2. Was sprayed. Thereafter, a far-infrared heater was passed under conditions of 200 ° C. and 0.3 m / min, and the binder was fused to the entire surface of one side of the fiber substrate 1 to prepare a fiber substrate 1 with a binder.

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 26 parts of N, N, O-triglycidyl-p-aminophenol “jER (registered trademark)” 630 (Japan Epoxy Resin Co., Ltd.), 10 parts of bisphenol A type epoxy resin “EPON (registered trademark)” 825 (manufactured by Japan Epoxy Resin Co., Ltd.), 10 parts of bisphenol F type epoxy resin “jER (registered trademark)” 806 (manufactured by Japan Epoxy Resin Co., Ltd.), 20 parts of hexahydrophthalic acid diglycidyl ester AK-601 (manufactured by Nippon Kayaku Co., Ltd.), 25 parts of biphenyl aralkyl type epoxy resin NC-3000 (manufactured by Nippon Kayaku Co., Ltd.) and “Kaneace (registered trademark)” MX416 ("Araldite" MY721 (tetraglycidyldiaminodiphenylmethane): 75 parts / core-shell polymer Volume average particle size: 100 nm, Core component: Cross-linked polybutadiene (glass transition temperature: -70 ° C), Shell: PMMA / glycidyl methacrylate / styrene copolymer): 25 parts masterbatch) 12 parts at a temperature of 70 ° C The mixture was mixed to obtain the main agent 1. It was 162 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the obtained main ingredient 1.

  Separately, as component [B-2], diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.) 19.8 parts, 3,3′-diaminodiphenylsulfone 3,3′- 7.9 parts of DAS (manufactured by Konishi Chemical Industry Co., Ltd.) and 7.9 parts of 4,4′-diaminodiphenylsulfone “Seica Cure (registered trademark)” S (manufactured by Seika Corporation) were stirred at a temperature of 130 ° C. The mixture was mixed while cooling to 70 ° C., and 1.0 part of t-butylcatechol TBC (Dainippon Ink Chemical Co., Ltd.) was added. The hardener 1 was obtained by mixing until no solid was present while stirring at a temperature of. It was 70 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the hardening | curing agent 1 obtained.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measurement method described above for the viscosity of a mixture (component [E]) in which 36.6 parts of the curing agent 1 was mixed with 103 parts of the main agent 1 obtained. 145 mPa · s.

Using the obtained mixture, a resin cured product was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 107 J / m ² , and the RTM molded fiber reinforced composite material Suitable for matrix resin.

"Preform fabrication"
After the obtained fiber base material 1 with a binder was cut into a predetermined size, the longitudinal direction of the carbon fiber was set to 0 degree, and the process was repeated three times based on [+ 45 ° / 0 ° / −45 ° / 90 °]. The layers were symmetrically laminated so that the 90-degree layers overlapped to obtain a total of 24 layers of the fiber substrate 1. The laminated fiber base material 1 is placed on the surface of the mold, the cavity sealed with the bag material (polyamide film) and the sealant is evacuated and atmospheric pressure is applied, and then the mold is transferred to a hot air dryer, The temperature was raised from room temperature to 80 ° C. by 3 ° C. per minute and heated at 80 ° C. for 1 hour. Thereafter, while maintaining the vacuum state of the cavity, it was cooled to 60 ° C. or lower in the atmosphere and released into the atmosphere to obtain a preform. Similarly, a carbon fiber having a longitudinal direction of 0 degree and a layer that is repeated twice on the basis of [+ 45 ° / 0 ° / −45 ° / 90 °] is laminated symmetrically so that the 90 ° layer overlaps, for a total of 16 A preform was also produced for the fiber substrate 1 of the layer. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
The obtained preform is placed on the surface of the mold, a polyester fabric subjected to a release treatment as a peel ply, and an aluminum wire mesh as a resin diffusion medium are arranged in order, and these are resinized with a bag material and a sealant. An inlet and a vacuum suction port were provided and sealed to form a cavity. Then, the inside of the cavity was sucked from the vacuum suction port by a vacuum pump to adjust the degree of vacuum to −90 kPa or less, and then the temperature of the mold and the preform was adjusted to 70 ° C. A hot air dryer was used for temperature adjustment.

  Separately, the main component of the thermosetting resin composition obtained above and the curing agent were mixed at a predetermined ratio, preliminarily heated at 70 ° C. for 30 minutes, and vacuum deaeration treatment was performed.

  The pre-heated and deaerated thermosetting resin composition was set in the resin injection port of the mold, and the thermosetting resin composition was injected into the vacuum cavity by atmospheric pressure. When the thermosetting resin composition reached the vacuum suction port, the resin injection port was closed, and the vacuum suction port was closed after holding for 1 hour while continuing the suction from the vacuum suction port.

  Next, the temperature is raised to 130 ° C. at a rate of 1.5 ° C. per minute and pre-cured at a temperature of 130 ° C. for 2 hours. Take out the pre-cured product from the mold and remove each auxiliary material such as peel ply, then heat it up to 1.5 ° C per minute in a hot air dryer to 180 ° C and cure at 180 ° C for 2 hours. Thus, a fiber reinforced composite material was obtained.

  The volume ratio of carbon fibers in the obtained fiber-reinforced composite material is 58% for both the pseudo isotropic 24 layers and the 16 layers, and the composite layers 1 including the carbon fiber bundle and the composite layers 2 not including the carbon fiber bundle are alternately formed. It was. As a result of measuring the average layer thickness of the composite layer 2 by the above-described method, it was found that the pseudo-isotropic 24 layer was 21 μm and the 16-layer was 24 μm.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) with the FE-SEM as described above, the composite layer 1 is a dark part and the composite layer 2 is a bright part. The plastic resin was concentrated on the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 5 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material by the method described above, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2.

“Compressive strength after impact (CAI) of fiber reinforced composites”
A test piece was prepared from the obtained fiber-reinforced composite material by the above-described method, and the CAI was measured. As a result, it was a high value of 228 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 220 MPa and was suitable for a structural member.

<Example 2>
"Manufacture of fiber substrate"
As component [A], carbon fiber bundle “Torayca (registered trademark)” T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity The unidirectional sheet-like reinforcing fiber bundle group was formed by drawing at a density of 1.8 fibers / cm with a warp of 294 GPa). A polyamide fiber bundle (polyamide 66, manufactured by Toray Industries, Inc .: 7 filaments, fineness: 1.7 tex) was used as the weft, and 3 strands / cm in a direction perpendicular to the unidirectional sheet-like reinforcing fiber bundle group. A fiber base material 2 having a plain weave structure in which carbon fibers are substantially arranged in one direction was produced by arranging in a density and using a loom to weave the warp and the weft so that they intersect each other. In addition, the fineness ratio of the weft to the warp fineness is 0.2%.

"Manufacture of fiber substrate with binder"
As component [D], hydroxyl-terminated polyethersulfone “Sumika Excel (registered trademark)” 5003P (manufactured by Sumitomo Chemical Co., Ltd.) 60 parts and bisphenol F type epoxy resin “jER (registered trademark)” 806 as a plasticizer 23.5 parts (manufactured by Japan Epoxy Resin Co., Ltd.), 12.5 parts biphenyl aralkyl type epoxy resin NC-3000 (manufactured by Nippon Kayaku Co., Ltd.), and triglycidyl isocyanurate “TEPIC (registered trademark)”-P ( (Nissan Chemical Industry) 4 parts were melt-kneaded at 210 ° C. with a twin screw extruder, and the resulting composition was freeze-ground and classified to give binder particles 2 having a volume average particle size of 105 μm and a glass transition temperature of 72 ° C. Obtained. The volume average particle diameter and glass transition temperature were measured in the same manner as in Example 1.

The obtained binder particles 2 were fused to the entire surface of one side of the fiber base 2 in the same manner as in Example 1 to prepare a fiber base 2 with a binder having a binder basis weight of 27 g / m ² .

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 25 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals), N, N, O-triglycidyl- 10 parts of p-aminophenol “jER (registered trademark)” 630 (manufactured by Japan Epoxy Resin Co., Ltd.), 35 parts of bisphenol A type epoxy resin “EPON (registered trademark)” 825 (manufactured by Japan Epoxy Resin Co., Ltd.), 15 parts of glycidylaniline GAN (manufactured by Nippon Kayaku Co., Ltd.) and “Kane Ace (registered trademark)” MX416 (“Araldite” MY721 (tetraglycidyldiaminodiphenylmethane): 75 parts / core-shell polymer (volume average particle diameter: 100 nm, core component) : Cross-linked polybutadiene (Glass transition temperature : -70 ° C.), the shell: PMMA / glycidyl methacrylate / styrene copolymer): The master batch) 20 parts 25 parts were mixed at a temperature of 70 ° C. to obtain a main agent 2. It was 143 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the obtained main ingredient 2.

  Separately, as component [B-2], diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.) 26.6 parts, 3,3′-diaminodiphenylsulfone 3,3′- 7.6 parts of DAS (manufactured by Konishi Chemical Industry Co., Ltd.) and 3.8 parts of 4,4′-diaminodiphenylsulfone “Seikacure (registered trademark)” S (manufactured by Seika Corporation) were stirred at a temperature of 130 ° C. The mixture was mixed while cooling to 70 ° C., and 1.0 part of t-butylcatechol TBC (Dainippon Ink Chemical Co., Ltd.) was added. The hardener 2 was obtained by mixing to a state where no solid matter was present while stirring at a temperature of. It was 72 mPa * s as a result of measuring the viscosity in 70 degreeC with the above-mentioned resin viscosity measuring method about the hardening | curing agent 2 obtained.

  Result of measuring the initial viscosity at 70 ° C. by the resin viscosity measuring method described above for the viscosity of the mixture (component [E]) in which 3 parts of curing agent 2 was mixed with 105 parts of the obtained main agent 2 120 mPa · s.

Using the obtained mixture, a cured resin was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 122 J / m ² , and the RTM molded fiber reinforced composite material Suitable for matrix resin.

"Preform preparation"
Using the obtained fiber base material 2 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material is 57% for the pseudo-isotropic 24 layer and 56% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 18 μm for the pseudo isotropic 24 layer and 20 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 10 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2. .

“Compressive strength after impact (CAI) of fiber reinforced composites”
As a result of measuring the CAI of the obtained fiber reinforced composite material in the same manner as in Example 1, it was a high value of 241 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 215 MPa, which was suitable for a structural member.

<Example 3>
"Manufacture of fiber substrate"
As the component [A], a carbon fiber bundle “Treka (registered trademark)” T800S-24k-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity The fiber yarn bundle ECE225 1/0 1Z (manufactured by Nittobo Co., Ltd., the number of filaments) as auxiliary warp yarns arranged at a density of 1.8 yarns / cm as warp yarns at a rate of 294 GPa) : 200 fibers, fineness: 22.5 tex) at a density of 1.8 fibers / cm to form a unidirectional sheet-like reinforcing fiber bundle group. Glass fiber bundle ECE225 1/0 1Z (manufactured by Nittobo Co., Ltd., number of filaments: 200, fineness: 22.5 tex) polyamide fiber bundle is used as the weft, and the direction orthogonal to the unidirectional sheet-like reinforcing fiber bundle group A unidirectional non-crimp fabric in which the auxiliary warp and the weft are woven so as to cross each other using a loom, and the carbon fibers are substantially arranged in one direction and have no crimp. The fiber base material 3 was produced. In addition, the fineness ratio of the weft and the auxiliary warp to the warp fineness is 2.2%.

"Manufacture of fiber substrate with binder"
The binder particle 2 obtained in Example 2 was used, and the fiber base material 3 with a binder having a binder basis weight of 27 g / m ² was prepared by fusing the entire surface of one side of the fiber base material 3 in the same manner as in Example 1. .

"Manufacture of thermosetting resin composition"
The main agent 2 and the curing agent 2 obtained in Example 2 were used. The mixing ratio was such that the main agent 2 was 39 parts and the curing agent 2 was 39 parts.

"Preform fabrication"
Using the obtained fiber base material 3 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material is 58% for the pseudo-isotropic 24 layer and 56% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 22 μm for the pseudo isotropic 24 layer and 21 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 10 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2. .

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber-reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a high value of 242 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 217 MPa, which was suitable for a structural member.

<Example 4>
"Manufacture of fiber substrate"
The fiber base material 3 obtained in Example 3 was used.

"Manufacture of fiber substrate with binder"
The fiber substrate 3 with a binder obtained in Example 3 was used.

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 51 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals), diglycidylaniline GAN (Nippon Kayaku ( 40 parts) and "Kaneace (registered trademark)" MX416 ("Araldite" MY721 (tetraglycidyldiaminodiphenylmethane): 75 parts / core-shell polymer (volume average particle size: 100 nm, core component: crosslinked polybutadiene (glass transition temperature: glass transition temperature)) −70 ° C.), shell: PMMA / glycidyl methacrylate / styrene copolymer): 25 parts of master batch) 12 parts were mixed at a temperature of 70 ° C. to obtain the base 3. It was 105 mPa * s as a result of measuring the viscosity in 70 degreeC with the above-mentioned resin viscosity measuring method about the obtained main ingredient 3.

  Separately, 29.3 parts of diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.), 3,3′-diaminodiphenylsulfone 3,3′- as constituent [B-2] 8.4 parts of DAS (manufactured by Konishi Chemical Industry Co., Ltd.) and 4.2 parts of 4,4′-diaminodiphenylsulfone “Seikacure (registered trademark)” S (manufactured by Seika Corporation) were stirred at a temperature of 130 ° C. The mixture was mixed while cooling to 70 ° C., and 1.0 part of t-butylcatechol TBC (Dainippon Ink Chemical Co., Ltd.) was added. The hardener 3 was obtained by mixing to a state where no solid matter was present while stirring at a temperature of. It was 70 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the hardening | curing agent 3 obtained.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measuring method described above for the viscosity of a mixture (component [E]) in which the main agent 3 was 103 parts and the curing agent 3 was 42.9 parts. , 90 mPa · s.

Using the obtained mixture, a cured resin was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 100 J / m ² , and the RTM molded fiber reinforced composite material Suitable for matrix resin.

"Preform fabrication"
The preform obtained in Example 3 was used.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

The carbon fiber volume content of the obtained fiber reinforced composite material is 57% for both the pseudo isotropic 24 layer and the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle are alternately formed. It was. The average layer thickness of the composite layer 2 was measured by the method described above. As a result, the pseudo isotropic 24 layer was 20 μm, and the 16 layer was 19 μm.
"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 10 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2. .

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber-reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a high value of 242 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 241 MPa, which was suitable for a structural member.

<Example 5>
"Manufacture of fiber substrate"
As component [A], carbon fiber bundle “Torayca (registered trademark)” T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity The fiberglass bundle ECDE-75-1 / 0-1.0Z (Nittobo Co., Ltd.) is used as auxiliary warp yarns that are aligned at a density of 1.8 yarns / cm as warp yarns at a rate of 294 GPa). Co., Ltd., the number of filaments: 800, the fineness: 67.5 tex) were aligned at a density of 1.8 fibers / cm to form a unidirectional sheet-like reinforcing fiber bundle group. Glass fiber bundle E-glass yarn ECE-225-1 / 0-1.0Z (manufactured by Nittobo Co., Ltd., number of filaments: 200, fineness: 22.5 tex) is used as the weft to reinforce the unidirectional sheet. Arranged at a density of 3 / cm in a direction perpendicular to the fiber bundle group, weaving using a loom so that the auxiliary warp and the weft intersect each other, carbon fibers are arranged substantially in one direction and there is no crimp A unidirectional non-crimp woven fabric was prepared and used as a fiber base 4. In addition, the fineness ratio of the weft to the warp fineness is 2.2%, and the fineness ratio of the auxiliary warp is 6.5%.

"Manufacture of fiber substrate with binder"
Using the binder particles 2 obtained in Example 2, it was allowed to spontaneously drop onto one side surface of the fiber substrate 4 while being measured with an embossing roll and a doctor blade, and uniformly dispersed through a vibration net, while the binder weight was reduced. Was 13.5 g / m ² . Thereafter, the binder particles and the fiber base material 4 were fused by passing through a far infrared heater under the conditions of 200 ° C. and 0.3 m / min. Subsequently, the binder particles 2 were sprayed in the same manner on the surface where the binder particles were not fused, so that the binder basis weight was 13.5 g / m ^2, and then fused to prepare a fiber substrate 4 with a binder.

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 43 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals), bisphenol F type epoxy resin “jER (registered) Trademark) "806 (Japan Epoxy Resin Co., Ltd.) 18 parts, diglycidyl-o-toluidine GON (Nippon Kayaku Co., Ltd.) 10 parts, biphenylaralkyl epoxy resin NC-3000 (Nippon Kayaku Co., Ltd.) ) 14 parts and “Kaneace®” MX416 (“Araldite” MY721 (tetraglycidyldiaminodiphenylmethane): 75 parts / core shell polymer (volume average particle size: 100 nm, core component: crosslinked polybutadiene (glass transition temperature: −70 ° C.) ), Shell: PMMA / G Glycidyl methacrylate / styrene copolymer): The master batch) 20 parts 25 parts were mixed at a temperature of 70 ° C. to obtain a main agent 4. It was 141 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the obtained main ingredient 4.

  Separately, as the constituent element [B-2], 26.1 parts of diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.), 3,3′-diaminodiphenylsulfone 3,3′- 5.6 parts of DAS (manufactured by Konishi Chemical Co., Ltd.) and 5.6 parts of 4,4′-diaminodiphenylsulfone “Seikacure (registered trademark)” S (manufactured by Seika Corporation) were stirred at a temperature of 130 ° C. The mixture was mixed while cooling to 70 ° C., and 2.0 parts of t-butylcatechol TBC (manufactured by Dainippon Ink & Chemicals, Inc.) was added. The hardener 4 was obtained by mixing to a state where no solid matter was present while stirring at a temperature of. It was 70 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the hardening | curing agent 4 obtained.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measuring method described above for the viscosity of a mixture (component [E]) in which 39.2 parts of the curing agent 4 was mixed with 105 parts of the main agent 4 obtained. 120 mPa · s.

Using the obtained mixture, a cured resin was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 149 J / m ² , and the RTM molded fiber reinforced composite material Suitable for matrix resin.

"Preform fabrication"
Using the obtained fiber base material 4 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material is 56% for the pseudo-isotropic 24 layer and 57% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 24 μm for the pseudo isotropic 24 layer and 23 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 5 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2. .

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a high value of 235 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 224 MPa, which was suitable for a structural member.

<Example 6>
"Manufacture of fiber substrate"
The fiber base material 4 obtained in Example 5 was used.

"Manufacture of fiber substrate with binder"
The binder particle 2 obtained in Example 2 was used and fused to the entire surface of one side of the fiber base material 4 in the same manner as in Example 1 to prepare a fiber base material 5 with a binder having a binder basis weight of 27 g / m ² . .

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 51 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals), diglycidyl-o-toluidine GON (Nipponization) (Manufactured by Yakuhin Co., Ltd.) 40 parts and "Kaneace (registered trademark)" MX416 ("Araldite" MY721 (tetraglycidyldiaminodiphenylmethane): 75 parts / core shell polymer (volume average particle size: 100 nm, core component: crosslinked polybutadiene (glass transition) Temperature: −70 ° C.) Shell: PMMA / Glycidyl methacrylate / styrene copolymer): 25 parts of master batch) 12 parts were mixed at a temperature of 70 ° C. to obtain the main agent 5. It was 82 mPa * s as a result of measuring the viscosity in 70 degreeC with the above-mentioned resin viscosity measuring method about the obtained main ingredient 5.

  Separately, as the constituent element [B-2], 28.5 parts of diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.), 3,3′-diaminodiphenylsulfone 3,3′- 8.1 parts of DAS (manufactured by Konishi Chemical Co., Ltd.) and 4.1 parts of 4,4′-diaminodiphenylsulfone “Seikacure (registered trademark)” S (manufactured by Seika Corporation) were stirred at a temperature of 130 ° C. The mixture was mixed while cooling to 70 ° C., and 1.0 part of t-butylcatechol TBC (Dainippon Ink Chemical Co., Ltd.) was added. The hardener 5 was obtained by mixing to a state where no solid matter was present while stirring at a temperature of. It was 74 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the hardening | curing agent 5 obtained.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measuring method described above for the viscosity of the mixture (component [E]) in which the main agent 5 was mixed with 103 parts of the main agent 5 and 41.7 parts of the curing agent 5. 76 mPa · s.

Using the obtained mixture, a cured resin was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 118 J / m ² , and the RTM molded fiber reinforced composite material Suitable for matrix resin.

"Preform fabrication"
Using the obtained fiber base material 5 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material is 59% for the pseudo-isotropic 24 layer and 57% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, the one with a pseudo-isotropic 24 layer was 20 μm and the one with a 16 layer was 22 μm.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 12 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2. .

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a high value of 238 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 227 MPa, which was suitable for a structural member.

<Example 7>
"Manufacture of fiber substrate"
The fiber base material 3 obtained in Example 3 was used.

"Manufacture of fiber substrate with binder"
As component [D], 70 parts of transparent nylon “Grillamide (registered trademark)” TR55 (Mitsubishi Engineering Plastics) and bisphenol A type epoxy resin “EPON (registered trademark)” 825 (Japan Epoxy Resin) as a plasticizer Co., Ltd.) 30 parts were melt-kneaded at 210 ° C. with a twin screw extruder, and the resulting composition was classified after freezing and pulverizing to obtain binder particles 3 having a volume average particle diameter of 95 μm and a glass transition temperature of 51 ° C. Obtained. The volume average particle diameter and glass transition temperature were measured in the same manner as in Example 1.

The obtained binder particles 3 were fused to the entire surface of one side of the fiber base material 3 in the same manner as in Example 1 to prepare a fiber base material 6 with a binder having a binder basis weight of 23 g / m ² .

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 34 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals), N, N, O-triglycidyl- 10 parts of p-aminophenol “jER (registered trademark)” 630 (manufactured by Japan Epoxy Resin Co., Ltd.), 35 parts of bisphenol F type epoxy resin “jER (registered trademark)” 806 (manufactured by Japan Epoxy Resin Co., Ltd.), 15 parts of glycidylaniline GAN (manufactured by Nippon Kayaku Co., Ltd.) and “Kane Ace (registered trademark)” MX416 (“Araldite” MY721 (tetraglycidyldiaminodiphenylmethane): 75 parts / core-shell polymer (volume average particle diameter: 100 nm, core component) : Cross-linked polybutadiene (glass transition temperature -70 ° C.), the shell: PMMA / glycidyl methacrylate / styrene copolymer): The master batch) 8 parts of 25 parts were mixed at a temperature of 70 ° C. to obtain a main agent 6. It was 134 mPa * s as a result of measuring the viscosity in 70 degreeC of the obtained main ingredient 6 with the above-mentioned resin viscosity measuring method.

  Separately, as component [B-2], 27.1 parts of diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.), 3,3′-diaminodiphenylsulfone 3,3′- 7.7 parts of DAS (manufactured by Konishi Chemical Industry Co., Ltd.) and 3.9 parts of 4,4′-diaminodiphenylsulfone “Seikacure (registered trademark)” S (manufactured by Seika Corporation) were stirred at a temperature of 130 ° C. The mixture was mixed while cooling to a temperature of 70 ° C., and 0.8 part of t-butylcatechol TBC (Dainippon Ink Chemical Co., Ltd.) was added. The mixture was mixed to a state where no solid matter was present while stirring at a temperature of 5 to obtain a curing agent 6. It was 72 mPa * s as a result of measuring the viscosity in 70 degreeC of the obtained hardening | curing agent 6 with the above-mentioned resin viscosity measuring method.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measuring method described above for the viscosity of a mixture (component [E]) in which 39.5 parts of the curing agent 6 was mixed with 102 parts of the main agent 6 obtained. 110 mPa · s.

Using the obtained mixture, a cured resin was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 132 J / m ² , and the RTM molded fiber reinforced composite material Suitable for matrix resin.

"Preform fabrication"
Using the obtained fiber base material 6 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The carbon fiber volume content of the obtained fiber reinforced composite material is 57% for both the pseudo isotropic 24 layer and the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle are alternately formed. It was. As a result of measuring the average layer thickness of the composite layer 2 by the above-described method, the one having a pseudo isotropic 24 layer was 20 μm and the one having 16 layers was 21 μm.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 10 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) of the obtained fiber-reinforced composite material in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 was larger than that of the composite layer 2. .

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a high value of 236 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 216 MPa, which was suitable for a structural member.

<Example 8>
"Manufacture of fiber substrate with binder"
The fiber substrate 5 obtained in Example 6 was used.

"Manufacture of thermosetting resin composition"
The main agent 5 and the curing agent 5 obtained in Example 6 were used. The mixing ratio was such that the main agent 5 was 103 parts and the curing agent 5 was 41.7 parts.

"Preform fabrication"
The preform obtained in Example 6 was used.

"Molding of fiber reinforced composite materials"
The obtained preform is placed on the surface of the mold, a polyester fabric subjected to a release treatment as a peel ply, and an aluminum wire mesh as a resin diffusion medium are arranged in order, and these are resinized with a bag material and a sealant. An inlet and a vacuum suction port were provided and sealed to form a cavity. Then, the inside of the cavity was sucked from the vacuum suction port by a vacuum pump to adjust the degree of vacuum to −90 kPa or less, and then the temperature of the mold and the preform was adjusted to 70 ° C. A hot air dryer was used for temperature adjustment.

  Separately, the main component of the thermosetting resin composition obtained above and the curing agent were mixed at a predetermined ratio, preliminarily heated at 70 ° C. for 30 minutes, and vacuum deaeration treatment was performed.

  The pre-heated and deaerated thermosetting resin composition was set in the resin injection port of the mold, and the thermosetting resin composition was injected into the vacuum cavity by atmospheric pressure. When the thermosetting resin composition reached the vacuum suction port, the resin injection port was closed, and the vacuum suction port was closed after holding for 1 hour while continuing the suction from the vacuum suction port.

  Next, the temperature was raised to 180 ° C. at a rate of 1.5 ° C. per minute and cured at a temperature of 180 ° C. for 2 hours to obtain a fiber-reinforced composite material.

  The volume content of carbon fibers of the obtained fiber reinforced composite material is 59% for the pseudo-isotropic 24 layer and 60% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 12 μm for the pseudo isotropic 24 layer and 10 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 is a mixture of light and dark parts, and the composite layer 2 is a light part. The thermoplastic resin also penetrated into the composite layer 1. The inside of the carbon fiber bundle of the composite layer 1 contained a thermosetting resin (component [D]) from the outer periphery of the bundle to 40 μm.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the number of core-shell polymer particles contained in the composite layer 1 and the composite layer 2 was almost the same. Met.

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was as high as 200 MPa, suitable for a structural member, but lower than that in Example 6.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared for the obtained fiber reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 210 MPa, which was suitable for a structural member, but was lower than Example 6.

<Comparative Example 1>
"Manufacture of fiber substrate"
The fiber substrate 1 obtained in Example 1 was used.

"Manufacture of thermosetting resin composition"
The main agent 1 and the curing agent 1 obtained in Example 1 were used. The mixing ratio was such that main agent 1 was 103 parts and curing agent 1 was 36.6 parts.

"Preform fabrication"
Using the obtained fiber base material 1 without a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform has various layers, has very low form stability during transportation, and is inferior in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The carbon fiber volume content of the obtained fiber reinforced composite material is 60% for the pseudo isotropic 24 layer and 61% for the 16 layer, and as a result of observing the cross section, the composite layer 2 is hardly present. It was. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 5 μm for the pseudo isotropic 24 layer and 2 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
The resulting fiber-reinforced composite material was analyzed for the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1. As a result, no thermoplastic resin was blended, so both the composite layer 1 and the composite layer 2 were used. It was a dark part.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the obtained fiber-reinforced composite material could not be observed because the composite layer 2 was hardly present.
“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a low value of 124 MPa and was not suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was 215 MPa, which was suitable for a structural member.

<Comparative example 2>
"Manufacture of fiber substrate with binder"
The fiber base material 2 with a binder obtained in Example 2 was used.

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 40 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals), N, N, O-triglycidyl- 10 parts of p-aminophenol “jER (registered trademark)” 630 (manufactured by Japan Epoxy Resin Co., Ltd.), 35 parts of bisphenol A type epoxy resin “EPON (registered trademark)” 825 (manufactured by Japan Epoxy Resin Co., Ltd.) 15 parts of glycidyl aniline GAN (manufactured by Nippon Kayaku Co., Ltd.) was mixed at a temperature of 70 ° C. to obtain the main agent 7. It was 124 mPa * s as a result of measuring the viscosity in 70 degreeC with the above-mentioned resin viscosity measuring method about the obtained main ingredient 7.

  The curing agent 2 obtained in Example 2 was used as the curing agent.

  Result of measuring the initial viscosity at 70 ° C. by the resin viscosity measuring method described above for the viscosity of the mixture (component [E]) in which 39.0 parts of curing agent 2 was mixed with 100 parts of the obtained main agent 8 100 mPa · s.

Using the obtained mixture, a cured resin was prepared by the above-described method, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 60 J / m ² and the viscosity was an RTM molded fiber reinforced composite. Although it was suitable for the matrix resin of the material, the fracture toughness was low.

"Preform fabrication"
Using the obtained fiber base material 2 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material is 56% for the pseudo-isotropic 24 layer and 57% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 18 μm for the pseudo isotropic 24 layer and 19 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 10 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the obtained fiber-reinforced composite material was not observed because the core-shell polymer particles were not blended.

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a high value of 234 MPa and was suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, the value was 190 MPa, which was not suitable for a structural member.

<Comparative Example 3>
"Manufacture of fiber substrate"
The fiber base material 3 obtained in Example 3 was used.

"Manufacture of thermosetting resin composition"
As component [B-1] constituting component [E], 60 parts of tetraglycidyldiaminodiphenylmethane “Araldite (registered trademark)” MY721 (manufactured by Huntsman Advanced Chemicals) and diglycidylaniline GAN (Nippon Kayaku ( 40 parts) was mixed at a temperature of 70 ° C. to obtain the main agent 8. It was 88 mPa * s as a result of measuring the viscosity in 70 degreeC of the obtained main ingredient 2 with the above-mentioned resin viscosity measuring method.

  As the curing agent, the curing agent 3 obtained in Example 4 was used.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measuring method described above for the viscosity of a mixture (component [E]) in which 42.9 parts of the curing agent 3 was mixed with 100 parts of the main agent 9 obtained. 76 mPa · s.

Using the obtained mixture, a cured resin was prepared by the method described above, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 58 J / m ² , and the RTM molded fiber reinforced composite material Although it was suitable for a matrix resin, the fracture toughness was low.

"Preform fabrication"
Using the obtained fiber base material 3 without a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform has various layers, has very low form stability during transportation, and is inferior in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material was 60% for both the pseudo isotropic 24 layer and the 16 layer, and as a result of observing the cross section, the composite layer 2 was hardly present. As a result of measuring the average layer thickness of the composite layer 2 by the above-described method, it was 3 μm in both of the pseudo isotropic 24 layer and the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
The resulting fiber-reinforced composite material was analyzed for the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1. As a result, no thermoplastic resin was blended, so both the composite layer 1 and the composite layer 2 were used. It was a dark part.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the obtained fiber-reinforced composite material was not observed because the core-shell polymer particles were not blended.

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a low value of 110 MPa and was not suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, the value was as low as 192 MPa, which was unsuitable for a structural member.

<Comparative example 4>
"Manufacture of fiber substrate"
As a component [A], carbon fiber bundle trading card “(registered trademark)” T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity Rate: 294 GPa) as a warp yarn, with a density of 1.8 yarns / cm, carbon fiber bundle “Torayca (registered trademark)” T300-6000 (Toray Industries, Inc.) as auxiliary warps arranged in parallel and alternately Made of PAN-based carbon fiber, number of filaments: 6,000, fineness: 396 tex, tensile elastic modulus: 230 GPa) at a density of 1.8 fibers / cm to form a unidirectional sheet-like reinforcing fiber bundle group . Glass fiber bundle E-glass yarn ECE-225-1 / 0-1.0Z (manufactured by Nittobo Co., Ltd., number of filaments: 200, fineness: 22.5 tex) is used as the weft to reinforce the unidirectional sheet. Arranged at a density of 3 / cm in a direction perpendicular to the fiber bundle group, weaving using a loom so that the auxiliary warp and the weft intersect each other, carbon fibers are arranged substantially in one direction and there is no crimp A unidirectional non-crimp fabric was prepared and used as the fiber base 5. In addition, the fineness ratio of the weft to the warp fineness is 2.2%, and the fineness ratio of the auxiliary warp is 38.3%.

"Manufacture of thermosetting resin composition"
The main agent 5 and the curing agent 5 obtained in Example 6 were used. The mixing ratio was such that the main agent 1 was 103 parts and the curing agent 1 was 41.7 parts.

"Preform fabrication"
Using the obtained fiber base material 5 without a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform has various layers, has very low form stability during transportation, and is inferior in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The carbon fiber volume content of the obtained fiber reinforced composite material is 62% for the pseudo-isotropic 24 layer and 61% for the 16 layer, and as a result of observing the cross section, the composite layer 2 is hardly present. It was. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 3 μm for the pseudo isotropic 24 layer and 2 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
The resulting fiber-reinforced composite material was analyzed for the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1. As a result, no thermoplastic resin was blended, so both the composite layer 1 and the composite layer 2 were used. It was a dark part.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the obtained fiber-reinforced composite material could not be observed because the composite layer 2 was hardly present.

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a low value of 115 MPa and was unsuitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was a low value of 193 MPa and was not suitable for a structural member.

<Comparative Example 5>
"Manufacture of fiber substrate"
As a component [A], carbon fiber bundle trading card “(registered trademark)” T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity Rate: 294 GPa) as a warp and a density of 1.8 yarns / cm, and a glass fiber bundle E-glass yarn ECE-225-1 / 0-1.0Z as an auxiliary warp arranged in parallel and alternately therewith (Nittobo Co., Ltd., filament number: 200, fineness: 135 tex) were drawn at a density of 1.8 strands / cm to form a unidirectional sheet-like reinforcing fiber bundle group. Glass fiber bundle E-glass yarn ECG-37-1 / 0-1.0Z (manufactured by Nittobo Co., Ltd., number of filaments: 800, fineness: 22.5 tex) is used as the weft, and the unidirectional sheet-like reinforcement is performed. Arranged at a density of 3 / cm in a direction perpendicular to the fiber bundle group, weaving using a loom so that the auxiliary warp and the weft intersect each other, carbon fibers are arranged substantially in one direction and there is no crimp A unidirectional non-crimp woven fabric was prepared and used as a fiber base 6. In addition, the fineness ratio of the weft to the warp fineness is 13.1%, and the fineness ratio of the auxiliary warp is 2.2%.

"Manufacture of thermosetting resin composition"
The main agent 7 and the curing agent 7 obtained in Example 8 were used. The mixing ratio was such that main agent 1 was 103 parts and curing agent 1 was 42.9 parts.

"Preform fabrication"
Using the obtained fiber base material 5 without a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform has various layers, has very low form stability during transportation, and is inferior in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

  The volume content of carbon fibers in the obtained fiber reinforced composite material is 61% for the pseudo-isotropic 24 layer and 62% for the 16 layer, and as a result of observing the cross section, the composite layer 2 is hardly present. It was. As a result of measuring the average layer thickness of the composite layer 2 by the above-described method, it was 4 μm for the pseudo isotropic 24 layer and 5 μm for the 16 layer.

"Distribution measurement of thermoplastic resin in fiber reinforced composites"
The resulting fiber-reinforced composite material was analyzed for the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1. As a result, no thermoplastic resin was blended, so both the composite layer 1 and the composite layer 2 were used. It was a dark part.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the obtained fiber-reinforced composite material could not be observed because the composite layer 2 was hardly present.

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber-reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a low value of 117 MPa, which was unsuitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, the value was as high as 202 MPa, which was suitable for a structural member.

<Comparative Example 6>
"Manufacture of fiber substrate"
As a component [A], carbon fiber bundle trading card “(registered trademark)” T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elasticity Rate: 294 GPa) as a warp yarn, with a density of 1.8 yarns / cm, carbon fiber bundle “Torayca (registered trademark)” T300-6000 (Toray Industries, Inc.) as auxiliary warps arranged in parallel and alternately Made of PAN-based carbon fiber, number of filaments: 6,000, fineness: 396 tex, tensile elastic modulus: 230 GPa) at a density of 1.8 fibers / cm to form a unidirectional sheet-like reinforcing fiber bundle group . Glass fiber bundle E-glass yarn ECG-37-1 / 0-1.0Z (manufactured by Nittobo Co., Ltd., number of filaments: 800, fineness: 22.5 tex) is used as the weft, and the unidirectional sheet-like reinforcement is performed. Arranged at a density of 3 / cm in a direction perpendicular to the fiber bundle group, weaving using a loom so that the auxiliary warp and the weft intersect each other, carbon fibers are arranged substantially in one direction and there is no crimp A unidirectional non-crimp woven fabric was prepared and used as a fiber substrate 7. In addition, the fineness ratio of the weft to the warp fineness is 13.1%, and the fineness ratio of the auxiliary warp is 38.3%.

"Manufacture of thermosetting resin composition"
As constituent element [B-1] constituting constituent element [E], 70 parts of bisphenol A type epoxy resin “EPON (registered trademark)” 825 (manufactured by Japan Epoxy Resin Co., Ltd.) and hexahydrophthalic acid diglycidyl ester AK 30 parts of -601 (manufactured by Nippon Kayaku Co., Ltd.) was mixed at a temperature of 70 ° C. to obtain the main agent 9. It was 40 mPa * s as a result of measuring the viscosity in 70 degreeC by the above-mentioned resin viscosity measuring method about the obtained main ingredient 9.

  100 parts of diethyltoluenediamine “jER Cure (registered trademark)” W (manufactured by Japan Epoxy Resin Co., Ltd.) was used as the curing agent 7.

  The initial viscosity at 70 ° C. was measured by the resin viscosity measuring method described above for the viscosity of a mixture (component [E]) in which 27.0 parts of the curing agent 8 was mixed with 100 parts of the obtained main agent 10. 45 mPa · s.

Using the obtained mixture, a resin cured product was prepared by the above-described method, and the glass transition temperature was measured. As a result, the resin fracture toughness G _IC was 63 J / m ² and the RTM molded fiber reinforced composite was measured. Although it was suitable for the matrix resin of the material, both the glass transition temperature and fracture toughness were low.

"Manufacture of fiber substrate with binder"
The binder particles 3 obtained in Example 7 were fused to the entire surface of one side of the fiber base material 7 in the same manner as in Example 1 to prepare a fiber base material 8 with a binder having a binder basis weight of 23 g / m ² .

"Preform fabrication"
Using the obtained fiber base material 8 with a binder, pseudo-isotropic, 24-layer and 16-layer preforms were produced in the same manner as in Example 1. Such a preform did not fall apart in each layer, had high form stability even during transportation, and was excellent in handleability.

"Molding of fiber reinforced composite materials"
Using the obtained preform, a fiber-reinforced composite material was obtained in the same manner as in Example 1.

The volume content of carbon fibers in the obtained fiber reinforced composite material is 57% for the pseudo-isotropic 24 layer and 58% for the 16 layer, and the composite layer 1 including the carbon fiber bundle and the composite layer 2 not including the carbon fiber bundle. Were alternately layered. As a result of measuring the average layer thickness of the composite layer 2 by the method described above, it was 18 μm for the pseudo isotropic 24 layer and 20 μm for the 16 layer.
"Distribution measurement of thermoplastic resin in fiber reinforced composites"
As a result of analyzing the distribution of the thermoplastic resin (component [D]) in the same manner as in Example 1 for the obtained fiber-reinforced composite material, the composite layer 1 was a dark part and the composite layer 2 was a bright part. Were concentrated in the composite layer 2. Further, the inside of the carbon fiber bundle of the composite layer 1 contained no thermoplastic resin in the inner region of 15 μm or more from the outer periphery of the bundle.

“Distribution measurement of core-shell polymer particles in fiber-reinforced composites”
As a result of analyzing the distribution of the core-shell polymer particles (component [C]) in the same manner as in Example 1, the obtained fiber-reinforced composite material was not observed because the core-shell polymer particles were not blended.

“Compressive strength after impact (CAI) of fiber reinforced composites”
The obtained fiber reinforced composite material was measured for CAI in the same manner as in Example 1. As a result, it was a low value of 107 MPa and was not suitable for a structural member.

"Perforated plate compressive strength after applying constant fatigue (OHC fatigue strength)"
A test piece was prepared from the obtained fiber-reinforced composite material by the method described above, and the OHC fatigue strength was measured. As a result, it was a low value of 193 MPa and was not suitable for a structural member.

Claims (18)

A fiber-reinforced composite material comprising at least the following components [A], [B], [C] and [D], comprising at least components [A], [B] and [C]. The composite layer 1 and the composite layer 2 including at least the constituent elements [B], [C], and [D] are alternately formed, and the composite layer 1 does not include the constituent element [D]. A fiber-reinforced composite material, wherein the composite layer 2 has an average layer thickness of 10 to 50 μm.
[A] a carbon fiber bundle having 6,000 to 70,000 filaments,
[B] A cured product obtained by curing a thermosetting resin composition containing at least the following components [B-1] and [B-2],
[B-1] Thermosetting resin containing at least one selected from epoxy resin, cyanate resin, bismaleimide resin, benzoxazine resin,
[B-2] a component capable of curing the component [B-1],
[C] Core-shell polymer particles having a volume average particle diameter of 1 to 500 nm,
[D] An amorphous thermoplastic resin containing in the molecule at least one linking group selected from an amide group, a sulfonyl group, and an imide group. 2. The fiber-reinforced composite material according to claim 1, wherein in the composite layer 1, the component [D] is not contained in an inner region of 20 μm or more from the outer periphery of the component [A]. The constituent element [C] content in the constituent element [B] constituting the composite layer 2 is less than the constituent element [C] content in the constituent element [B] constituting the composite layer 1. The fiber-reinforced composite material according to 1 or 2. Component [B] is a cured product obtained by heat-curing an epoxy resin composition in which component [B-1] is an epoxy resin and component [B-2] is an aromatic polyamine. The fiber-reinforced composite material according to any one of the above. The fiber-reinforced composite material according to any one of claims 1 to 4, wherein the core component of the constituent element [C] is a crosslinked polybutadiene. The fiber reinforced composite material according to any one of claims 1 to 5, wherein a glass transition temperature of a core component of the constituent element [C] is -40 ° C or lower. The fiber reinforced composite material according to any one of claims 1 to 6, wherein the glass transition temperature of the constituent element [D] is 150 ° C or higher. The fiber-reinforced composite material according to any one of claims 1 to 7, wherein the constituent element [D] is a hydroxyl group-terminated polyethersulfone or grillamide. The constituent element [A] is a warp made of a carbon fiber bundle, an auxiliary warp of a fiber bundle made of glass fiber or chemical fiber arranged in parallel to this, and a glass fiber or chemical fiber arranged so as to be orthogonal to these. 2. A non-crimp woven fabric in which a woven fabric is formed by holding the carbon fiber bundle integrally by intersecting the auxiliary warp and the weft with each other. The fiber reinforced composite material in any one of -8. The fiber-reinforced composite material according to claim 9, wherein the fineness of the auxiliary warp of the fiber bundle made of glass fiber or chemical fiber is 20% or less of the fineness of the warp made of carbon fiber bundle. The fiber-reinforced composite material according to claim 9 or 10, wherein the fineness of the weft of the fiber bundle made of glass fiber or chemical fiber is 10% or less of the fineness of the warp made of the carbon fiber bundle. A fiber base material provided with a composition having a form selected from a fibrous form, a sheet form, and a particulate form containing the constituent element [D] is disposed in the mold on at least one surface of the sheet-like article containing the constituent element [A]. Then, after injecting and impregnating the component [E], a method for producing a fiber-reinforced composite material is cured by heating.
[A] a carbon fiber bundle having 6,000 to 70,000 filaments,
[E] Thermosetting that includes at least the following components [B-1], [B-2] and [C], and has a viscosity of not more than 300 mPa · s within 5 minutes from the start of measurement at a temperature of 70 ° C. Resin composition,
[B-1] Thermosetting resin containing at least one selected from epoxy resin, cyanate resin, bismaleimide resin, benzoxazine resin,
[B-2] a component capable of curing the component [B-1],
[C] Core-shell polymer particles having a volume average particle diameter of 1 to 500 nm,
[D] An amorphous thermoplastic resin containing in the molecule at least one linking group selected from an amide group, a sulfonyl group, and an imide group. The component [E] is a two-component epoxy resin composition composed of a main agent composed of at least the components [B-1] and [C] and a curing agent composed of at least the component [B-2]. The manufacturing method of the fiber reinforced composite material of Claim 12 including the process of mixing this main ingredient and this hardening | curing agent. The fiber reinforced according to claim 12 or 13, wherein the component [D] has a functional group capable of reacting with the component [B-1] or [B-2] at a terminal or a side chain of the molecular structure. Composite material. The sheet-like material containing the component [A] was arranged so as to be orthogonal to the warp made of a carbon fiber bundle, the auxiliary warp of the fiber bundle made of glass fiber or chemical fiber arranged in parallel therewith. It consists of wefts of fiber bundles made of glass fibers or chemical fibers, and the auxiliary warp and the wefts cross each other to form a non-crimp fabric in which the carbon fiber bundle is held together to form a fabric. The fiber substrate is placed between a rigid open mold and a flexible film, and a vacuum pump is used to draw a vacuum between the rigid open mold and the flexible film, and a resin mixture is injected. The method for producing a fiber-reinforced composite material according to claim 12, wherein the fiber-reinforced composite material is cured by heating after impregnation. The method for producing a fiber-reinforced composite material according to claim 15, wherein the fineness of the auxiliary warp of the fiber bundle made of glass fiber or chemical fiber is 20% or less of the fineness of the warp made of carbon fiber bundle. The method for producing a fiber-reinforced composite material according to claim 15 or 16, wherein the fineness of the weft of the fiber bundle made of glass fiber or chemical fiber is 10% or less of the fineness of the warp made of the carbon fiber bundle. After injecting the resin mixture containing the component [B] and the component [C], the temperature is raised to an arbitrary temperature in the range of 50 to 140 ° C. to perform primary curing, and then to an arbitrary temperature in the range of 160 to 180 ° C. The manufacturing method of the fiber reinforced composite material in any one of Claims 12-17 which heats up and performs secondary curing.