JP2013181112A - Binder composition, reinforcing fiber base material, preform, fiber-reinforced composite material and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a binder composition excellent in long-term storage stability and impact resistance, and a carbon fiber composite material having excellent impact resistance against external shock and high compression strength after impact properties (CAI) by applying the binder composition, and most suitable as aircraft members, etc.SOLUTION: There is provided a binder composition containing an element [A]: an amorphous polyamide having a dicyclohexylmethane skeleton in a molecule and a glass transition temperature of ≥140°C, an element [B]: a specific sulfonamide compound and an element [C]: a sulfonamide compound.

Description

  The present invention relates to a fiber reinforced composite material and a method for producing the same, and a preform, a reinforced fiber base material, and a binder composition used for the fiber reinforced composite material.

  Conventionally, fibers made of reinforced fibers such as glass fibers, carbon fibers, and aramid fibers, and cured products of thermosetting resins such as unsaturated polyester resins, vinyl ester resins, epoxy resins, phenol resins, cyanate ester resins, and bismaleimide resins. Reinforced composite materials are lightweight, yet have excellent mechanical properties such as strength and elastic modulus, heat resistance, and corrosion resistance, so they are used in aircraft members, spacecraft members, automobile members, ship members, civil engineering materials, sports equipment, etc. It has been applied in many fields. Especially in applications where high performance is required, fiber reinforced composite materials using continuous fibers are used, carbon fibers with excellent specific strength and specific elastic modulus are used as reinforcing fibers, and mechanical properties and heat resistance are used as matrix resins. In addition, many epoxy resins having high chemical resistance and excellent adhesion to carbon fibers are used.

  Fiber reinforced composite materials are manufactured by various methods. Resin transfer molding (in which a fiber reinforced composite material is obtained by impregnating a reinforced fiber base placed in a mold with a liquid thermosetting resin and heat curing. Resin Transfer Molding (hereinafter abbreviated as RTM) has recently attracted attention as a low-cost molding method with excellent productivity.

  When manufacturing a fiber reinforced composite material by RTM, a preform is prepared by processing a reinforcing fiber base into a shape close to a desired composite material, and after the preform is placed in a mold, a liquid thermosetting resin is injected. Many methods are adopted.

  As a method for producing a preform, several methods such as a method of creating a three-dimensional braid from reinforcing fibers and a method of stacking and stitching reinforcing fiber fabrics are known. As a highly versatile method, There is a method of laminating and shaping a sheet-like substrate such as a reinforced fiber fabric using a hot-melt binder (also called a tackifier).

  As these hot-melt binders, resin compositions that do not have tackiness at room temperature but soften at high temperatures and have adhesiveness are used. For example, as described in Patent Document 1, both a thermoplastic resin and a thermosetting resin can be applied.

  When a thermoplastic resin is used as a binder component, the glass transition temperature or melting point of the thermoplastic resin is relatively high, so a very high temperature is required to heat-bond the reinforcing fiber bases together, resulting in poor productivity. There's a problem.

  Moreover, when using a thermosetting resin as a binder component, for example, the type which has sclerosis | hardenability with the binder simple substance as described in patent documents 2-4, for example, patent documents 5-6 are described. There is a type in which such a binder alone has no curability. The former is excellent in that it can be cured without depending on the liquid thermosetting resin, and the latter is excellent in storage stability.

  On the other hand, a fiber reinforced composite material using a thermosetting resin such as an epoxy resin as a matrix resin generally has a lower fracture toughness of a cured product of the thermosetting resin than a thermoplastic resin. There is a problem that impact resistance 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, and when an impact is applied to the fiber reinforced composite material, a high stress is generated between the layers, and a crack is generated. In order to suppress the generation of cracks, it is effective to increase the plastic deformation ability of the thermosetting resin, and as a means for that, it is effective to blend a thermoplastic resin having an excellent plastic deformation ability.

  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 described in Patent Documents 7 to 8, thereby increasing the toughness. However, when a thermoplastic resin is blended with a thermosetting resin, the viscosity is remarkably increased, so that it is not suitable for an RTM with a limited viscosity of the matrix resin.

  As another means, there is known a technique in which a thermoplastic resin or an elastomer is present between layers where cracks easily occur. This technique can also be applied to RTM by applying the binder technology described above. For example, in a fiber reinforced composite material produced by injecting and curing a liquid thermosetting resin into a preform obtained by bonding sheet-like substrates such as reinforced fiber fabrics using a binder made of a thermoplastic resin The binder component will be present between the layers.

  When a thermoplastic resin is used as the binder component, as described above, a very high temperature is required for heat fusion, and there is a problem that productivity is inferior. In order to solve this problem, for example, as described in Patent Documents 9 to 12, there is a method of adjusting the processing temperature by blending a plasticizer with a thermoplastic resin.

  However, in the field of thermoplastic resins, for example, as described in Non-Patent Document 1, when a large amount of plasticizer is blended, it is compatible with the thermoplastic resin due to fluctuations in temperature and humidity during storage. It is known that the plasticizers separated and appear on the surface of the thermoplastic resin.

  When the plasticizer is separated, the amount of the plasticizer compatible with the thermoplastic resin is reduced, so that the plasticizing effect is weakened. As a result, the glass transition temperature of the binder may fluctuate, and the fiber reinforced composite material which is the final form May affect the characteristics of

In order to prevent the plasticizer from being separated, it is necessary to strictly manage the storage environment such as temperature and humidity, and the management cost becomes very high.
For the reasons as described above, regarding the binder mainly composed of a thermoplastic resin that is effective for improving the impact resistance of the fiber reinforced composite material, the separation of the plasticizer to be compounded for improving the workability is suppressed, and the binder is strict. There is a need for technology that enables stable storage over the long term without managing the storage environment.

JP-A-2-198815 US Pat. No. 5,427,725 US Pat. No. 5,698,318 US Pat. No. 5,369,192 US Pat. No. 4,992,228 US Pat. No. 5,217,766 Japanese Patent Laid-Open No. 62-297314 JP-A 62-297315 International Publication No. 2011/0334040 JP 2004-43621 A JP 2005-53961 A JP 2006-326892 A

"Industrial Materials", Nikkan Kogyo Shimbun, December 2011, p65

  In view of the background of such prior art, the present invention can provide a fiber-reinforced composite material excellent in impact resistance, optimal for aircraft primary structural members, and excellent in storage stability, and the binder composition An object of the present invention is to provide a reinforcing fiber substrate and a preform to which the object is applied.

The present invention employs the following means in order to solve such problems. That is, the binder resin composition of the present invention is a binder composition containing the following component [A], component [B] and component [C].
Component [A]: Amorphous polyamide component having a dicyclohexylmethane skeleton in the molecule and a glass transition temperature of 140 ° C. or higher [B]: A sulfonamide compound represented by the following formula (I)

(In formula (I), R ¹ is a substituent having 1 to 3 aromatic rings.)
Component [C]: a sulfonamide compound represented by the following formula (II).

(In formula (II), R ² and R ³ are each a substituent selected from hydrogen, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group, and a halogen group.)
Examples of the halogen include fluorine, chlorine, bromine and the like.

  In a preferable embodiment of the binder composition of the present invention, the dicyclohexylmethane skeleton in the component [A] is 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane skeleton, and a more preferable embodiment is the component [A]. Containing 100 to 100 parts by mass, the component [B] and the component [C] are contained in an amount of 11 to 67 parts by mass, and the ratio of the blending amount of the component [B] and the component [C] is 1: 1 to 0.5: 1 and the glass transition temperature is 40 to 110 ° C.

A preferred embodiment of the reinforcing fiber substrate of the present invention is one in which the binder composition of the present invention is applied to at least one side, and a more preferred embodiment is a warp composed of carbon fiber bundles and glass fibers arranged parallel thereto. Alternatively, the auxiliary warp of the fiber bundle made of the chemical fiber and the weft made of the glass fiber or the chemical fiber arranged so as to be orthogonal thereto, and the auxiliary warp and the weft intersect each other so that the carbon fiber bundle is integrated. It is a non-crimp structure woven fabric that is held in a woven fabric, and the binder composition is applied to both surfaces of the reinforcing fiber base with a basis weight of 5 to 50 g / m ² .

  In a preferred embodiment of the preform of the present invention, the reinforcing fiber base material is laminated, and the binder composition is present between layers of the reinforcing fiber base material.

  The preferable aspect of the fiber reinforced composite material of this invention contains the hardened | cured material of the said preform and a thermosetting resin composition.

  In a preferred embodiment of the method for producing a fiber-reinforced composite material of the present invention, the preform is placed in a cavity formed by a rigid open mold and a flexible film, the cavity is sucked by a vacuum pump, The step of injecting the liquid thermosetting resin composition into the cavity from the injection port with the differential pressure of the above and impregnating the preform, followed by heat curing the liquid thermosetting resin composition.

  The binder composition of the present invention can be stably stored for a long time because there is no separation of the plasticizer, and the reinforcing fiber substrate to which the binder composition of the present invention is applied is preformed by fixing its form by heating. The fiber reinforced composite material molded with RTM using the obtained preform has excellent impact resistance against external impact and has high post-impact compressive strength (CAI). It can be suitably used for structural members such as aircraft members, spacecraft members, automobile members, and ship members.

The binder composition of the present invention comprises at least the following component [A], component [B], and component [C].
Component [A]: Amorphous polyamide component having a dicyclohexylmethane skeleton in the molecule and a glass transition temperature of 140 ° C. or higher [B]: A sulfonamide compound component represented by the above formula (I) [C]: Sulfonamide compound represented by the above formula (II)

  Here, the “amorphous” of the amorphous polyamide defined as the constituent element [A] is specifically, when the polyamide is measured with a differential scanning calorimeter (DSC) according to JIS K7121 (1987). In addition, the heat of crystal fusion is 5 cal / g or less. The heat of crystal melting is preferably 1 cal / g or less. In order to satisfy such characteristics, in the present invention, a polyamide containing a diamine unit having a dicyclohexylmethane skeleton as an essential component is used. Examples of such diamines include 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane and 4,4′-diaminodicyclohexylmethane, which may be used alone or in combination. it can. Among diamines having a dicyclohexylmethane skeleton, in particular, 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane can be preferably used because a polyamide having an excellent balance of physical properties can be obtained.

  In addition to the above-described components, the amorphous polyamide as the constituent element [A] includes, for example, a diamine having one cyclohexane ring in the molecule, such as 1,3-bisaminomethylcyclohexane, 1,4-bis. A small amount of aminomethylcyclohexane or the like can be copolymerized.

  The amorphous polyamide as the constituent element [A] can be obtained by polymerizing the diamine and the dicarboxylic acid. Preferred examples of the dicarboxylic acid include adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, and the like.

  In order to obtain the amorphous polyamide as the constituent element [A], it is preferable to polymerize at a ratio of 95 to 30% by mass of diamine and 5 to 70% by mass of dicarboxylic acid.

  Such an amorphous polyamide must have a glass transition temperature measured by a differential scanning calorimeter (DSC) of 140 ° C. or higher according to JIS K7121 (1987), preferably 150 ° C. or higher. When the glass transition temperature of the amorphous polyamide is lower than 140 ° C., the heat resistance of the obtained fiber-reinforced composite material is lowered, and the mechanical properties are particularly lowered at a high temperature after water absorption. By setting the glass transition temperature to 140 ° C. or higher, deterioration of physical properties can be suppressed.

  The amorphous polyamide can be synthesized as described above, or a commercially available one can be used. Commercially available products are “Novamid” (registered trademark) (manufactured by Mitsubishi Engineering Plastics), “Gramide” (registered trademark) (manufactured by Toyobo Co., Ltd.), “Grillamide” (registered trademark) TR (MS Chemie Japan) And “Trogamide” (registered trademark) T (manufactured by Daicel-Evonik Co., Ltd.).

  The binder composition of the present invention, for example, in order to suppress the phenomenon that the binder compositions are fused together at a temperature during storage and transportation to form an aggregate, or the plasticizer component to be blended is separated. It is important that the temperature is higher than a specific glass transition temperature, and is lower than a specific glass transition temperature so that the shape of the preform can be fixed at a relatively low temperature, for example, a temperature range of 60 to 150 ° C. is important. Specifically, the glass transition temperature of the binder composition is preferably in the temperature range of 40 to 110 ° C, more preferably in the range of 50 to 100 ° C, and still more preferably in the range of 60 to 95 ° C. Here, the glass transition temperature of the binder composition is a value obtained by measurement according to JIS K7121 (1987).

In the present invention, the constituent element [B] is a sulfonamide compound represented by the above formula (I). Here, R ¹ in the chemical formula is essential to be a substituent having 1 to 3 aromatic rings.

  The sulfonamide compound of component [B] is blended with component [A] as a so-called plasticizer in order to adjust the glass transition temperature of the resulting binder composition to be in the temperature range of 40 to 110 ° C.

In the present invention, component [B] is a substituent R ¹ from the viewpoint of excellent compatibility with the amorphous polyamide is a component [A] is represented by the following formula (III) ~ (XIII) Preferably there is.

  Here, the compatible state is a state in which no separated solid phase exists in the continuous layer in the observation at a magnification of 50 times using a laser microscope.

Examples of the sulfonamide compound of the constituent element [B] include N-phenyl-p-toluenesulfonamide, N-phenyl-o-toluenesulfonamide, N-benzyl-4-methylbenzenesulfonamide, N-benzyl-3. -Methylbenzenesulfonamide, N- (biphenyl-4-yl) -4-methylbenzenesulfonamide, N- (biphenyl-4-yl) -3-methylbenzenesulfonamide, 4-methyl-N- (4- ( 2-phenylpropan-2-yl) phenyl) benzenesulfonamide, 3-methyl-N- (4- (2-phenylpropan-2-yl) phenyl) benzenesulfonamide, N- (4-benzylphenyl) -4 -Methylbenzenesulfonamide, N- (4-benzylphenyl) -3-methylbenzenesulfone Amide, p- (p-toluenesulfonylamide) diphenylamine, 3-methyl-N- (4- (phenylamino) phenyl) benzenesulfonamide, N- (4- (4-butylamino) phenylamino) phenyl) -4 -Methylbenzenesulfonamide, N- (4- (4-butylamino) phenylamino) phenyl) -3-methylbenzenesulfonamide, 4-methyl-N- (4- (phenylsulfonyl) phenyl) benzenesulfonamide, 3 -Methyl-N- (4- (phenylsulfonyl) phenyl) benzenesulfonamide, N- (4-benzoylphenyl) -4-methylbenzenesulfonamide, N- (4-benzoylphenyl) -3-methylbenzenesulfonamide, 4-Methyl-N- (naphthalen-2-yl) benzenesulfone 3-methyl-N- (naphthalen-2-yl) benzenesulfonamide, 4-methyl-N- (4- (naphthalen-2-ylamino) phenyl) benzenesulfonamide, 3-methyl-N- (4- (Naphthalen-2-ylamino) phenyl) benzenesulfonamide and the like. Among them, it is preferable that the substituent of R ¹ is a substituent having one or two aromatic rings in component [B], more preferably 2. The R ¹ substituent of the constituent element [B] has one or more aromatic rings, whereby an excellent plasticizing effect can be obtained, and the R ¹ substituent of the constituent element [B] is three. By having the following aromatic ring, since the melting point of the sulfonamide compound is not too high, the glass transition temperature of the binder composition can be adjusted to 110 ° C. or lower.

  Such sulfonamide compounds can be used alone or in combination of two or more.

In the present invention, the constituent element [C] is a sulfonamide compound represented by the above formula (II). Here, it is essential that R ^{2 to} R ³ in the chemical formula are each a substituent selected from hydrogen, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group, and a halogen group such as fluorine, chlorine, and bromine.

  The sulfonamide compound of the constituent element [C] coexists with the constituent element [B], so that the constituent elements [B] and [C], which are plasticizers, are stored in the environment of storage or transportation of the resulting binder composition. Separation from the binder composition can be suppressed, and the storage stability of the binder composition can be greatly improved.

  In the present invention, as the sulfonamide compound of the component [C], for example, o-toluenesulfonamide, p-toluenesulfonamide, N-ethyl-o / p-toluenesulfonamide, N-cyclohexyl-p-toluenesulfonamide , N-cyclohexyl-o-toluenesulfonamide, p-ethylbenzenesulfonamide, o-ethylbenzenesulfonamide, Nn-butylbenzenesulfonamide, and the like. . Among these, o-toluenesulfonamide, p-toluenesulfonamide, and a mixture thereof are preferable because they can significantly suppress the separation of the plasticizer when used in combination with the component [B].

  The binder composition of the present invention contains 11 to 67 parts by mass of the component [B] and the component [C] in total with respect to 100 parts by mass of the component [A], and the component [B] It is preferable that the ratio of the compounding amount of the component [C] is 1: 1 to 0.5: 1, and more preferably, the component [B] and the component [ C] is contained in an amount of 11 to 42 parts by mass, and the ratio of the blending amount of the constituent element [B] and the constituent element [C] is 1: 1 to 0.8: 1. By making the compounding quantity of component [A], component [B], and component [C] into this range, since the glass transition temperature of a binder composition can be adjusted to the temperature range of 40-110 degreeC, it is preferable.

  Moreover, it is preferable that the ratio of the compounding quantity of component [B] and component [C] is 1: 1-0.5: 1, More preferably, it is 1: 1-0.8: 1. The closer the ratio, the better the effect of suppressing the separation of the plasticizer.

  In the binder composition of the present invention, a thermoplastic elastomer can be further blended as the component [D] within a range not impairing the effects of the present invention. Here, the thermoplastic elastomer is a block copolymer having a hard segment component and a soft segment component in the molecule, and has a glass transition temperature of 25 ° C. or lower and a melting point of 25 ° C. or higher. Then, it is a polymer that exhibits fluidity and exhibits rubber elasticity when cooled to a temperature between the glass transition temperature and the melting point. By blending the thermoplastic elastomer into the binder composition, the deformability of the binder composition and the adhesion to the reinforcing fibers at the temperature when fixing the shape of the preform, for example, in the range of 60 to 150 ° C., are improved. And there exists an advantage that the compressive strength after impact (CAI) of the fiber reinforced composite material obtained improves.

  As the thermoplastic elastomer, one or more selected from thermoplastic elastomers such as urethane elastomers, polyester elastomers, and polyamide elastomers can be used. In particular, a polyamide-based thermoplastic elastomer, that is, a polyamide elastomer, can be suitably used because of its excellent balance of physical properties such as heat resistance and toughness.

  The polyamide-based thermoplastic elastomer is a block copolymer in which polyamide such as polyamide 6 or polyamide 12 is a hard segment component and polyester or polyol is a soft segment component. Among them, a polyamide elastomer having a hard segment component of a polyamide based on a polymerized fatty acid or dimer acid is preferably used because of its excellent balance of hydrolyzability, heat resistance and toughness.

  The thermoplastic elastomer can be synthesized or commercially available. Commercially available products include, for example, “Hytrel” (registered trademark) (manufactured by Toray DuPont), which is a polyester elastomer, “Belprene” (registered trademark) (manufactured by Toyobo), and “PANDEX” (which is a urethane elastomer) ( (Registered trademark) (manufactured by DIC Bayer Polymer Co., Ltd.), "Milactolan" (registered trademark) (manufactured by Nippon Milactolan Co., Ltd.), polyamide elastomer "UBESTA XPA" (registered trademark) (manufactured by Ube Industries, Ltd.) "GRILFLEX" (registered trademark) (manufactured by Ms. Chemie Japan Co., Ltd.). Among them, the TPAE series (made by Fuji Kasei Kogyo Co., Ltd.), which is a polyamide elastomer based on polymerized fatty acid or dimer acid, can be preferably used for the above reasons.

  Content of the thermoplastic elastomer which is component [D] becomes like this. Preferably it is 5-25 mass parts, More preferably, it is 7-20 mass parts. By making content of component [D] into such a range, the heat deformation property of the obtained binder composition and adhesiveness with a reinforced fiber can be improved, and the compressive strength after impact of the obtained fiber reinforced composite material ( CAI) can be improved.

  The binder composition of the present invention further includes components other than the constituent element [A], the constituent element [B], the constituent element [C] and the constituent element [D], for example, a hinder within the range not impairing the effects of the present invention. Antioxidants such as dophenol and hindered amines; UV absorbers such as salicylic acid-based, benzophenone-based, and triazine-based materials; rubber particles, core-shell polymer particles; inorganic particles, and the like can be appropriately blended.

  The fiber reinforced composite material generally has a laminated structure, and when an impact is applied to the fiber reinforced composite material, high stress is generated between the layers, and peeling damage occurs. Therefore, when improving the impact resistance against an external impact, the toughness of the resin layer forming the interlayer of the fiber reinforced composite material may be improved. As the matrix resin forming the fiber reinforced composite material, a thermosetting resin, particularly an epoxy resin, which is a brittle material is often used. In order to improve the toughness of an epoxy resin, a technique for blending a thermoplastic resin is known. However, in the case of RTM, since the matrix resin is desired to have a low viscosity, it is not preferable to previously dissolve a thermoplastic resin that significantly increases the viscosity in the matrix resin.

  Therefore, when the thermoplastic resin is dissolved in the matrix resin, it is preferably dissolved during molding. However, in this case, since the solubility of the thermoplastic resin changes due to variations in molding conditions, particularly temperature and temperature rise rate, it is difficult to stably develop toughness. In particular, aircraft members and the like are often large and have complicated shapes, and when such members are molded, the molding conditions are likely to vary.

  From the above, it is preferable that the binder composition of the present invention is hardly dissolved in an epoxy resin that is frequently used as a main component of a matrix resin.

  The amorphous polyamide, which is the constituent element [A] in the present invention, has very poor compatibility with the epoxy resin and is insoluble in the epoxy resin alone, so that the constituent element is 100 parts by mass with respect to 100 parts by mass of the constituent element [A]. 11 to 67 parts by mass of [B] and component [C] are combined, and the ratio of the blending amount of component [B] and component [C] is in the range of 1: 1 to 0.5: 1. As a result, the binder composition is significantly less likely to be dissolved in the epoxy resin. In particular, in the case where the component [A] is a polyamide containing 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane units, this tendency becomes remarkable, which is preferable.

  As the form of the binder composition of the present invention, a film, tape, long fiber, short fiber, spun yarn, woven fabric, knit, non-woven fabric, net-like body, particle and the like provided with through holes can be employed. When a member is molded using a reinforcing fiber substrate in which the binder composition of the present invention and reinforcing fibers are combined, the reinforcing fiber substrate is shaped into a complicated shape. In that case, since it is a form of particle | grains and a nonwoven fabric that is excellent in shape followability, it is preferable that the shape of a binder composition is a particle | grains and a nonwoven fabric.

  When the shape of the binder composition of the present invention is a particle, the volume average particle size measured with a laser diffraction / scattering type particle size distribution analyzer is preferably 30 to 200 μm according to JIS Z8825-1 (2001). If it is 35-180 micrometers, it is still more preferable. Here, Partica LA-950V2 (manufactured by Horiba, Ltd.) was used as a laser diffraction / scattering type particle size distribution measuring apparatus, and the number of acquisitions was 15 times. The resulting particle size distribution assumes that the particles to be measured are spherical. When the actual shape of the particles is non-spherical (indefinite particles), the resulting particle size distribution is broad. In addition, when the particles to be measured are needle-shaped, the minor axis signal is usually difficult to read, and the obtained particle size distribution is that of the major axis. By setting the volume average particle size to 30 μm or more, the particles do not excessively enter the reinforcing fiber base, and the effect of binding the reinforcing fiber base can be efficiently expressed even with a small amount of the binder composition. Further, the fluidity of the particles can be made sufficient, and the handling of the binder composition can be facilitated. On the other hand, by setting the volume average particle size to 200 μm or less, it is possible to prevent waviness when the preform is formed and adversely affect the physical properties of the fiber-reinforced composite material.

When the shape of the binder composition of the present invention is a nonwoven fabric, both short fibers and long fibers can be used as the fibers. Moreover, it is preferable that the diameter of a fiber exists in the range of 1-30 micrometers, More preferably, it exists in the range of 1-10 micrometers. If the fiber diameter is smaller than 1 μm, the fiber may not be easily manufactured. However, when the fiber diameter is larger than 30 μm, the thickness between layers becomes larger than necessary, and the fiber volume content (Vf) decreases, so that the mechanical properties such as the strength and elastic modulus of the fiber reinforced plastic deteriorate. There is. Weight per unit area of the nonwoven fabric, i.e. basis weight is preferably in the range of from 1 to 20 g / ^{m 2,} more preferably in the range of 1 to 10 g / ^{m 2.} When the basis weight is larger than 20 g / m ² , the interlayer thickness becomes unnecessarily large and the fiber volume content (Vf) becomes small, so that the mechanical properties such as strength and elastic modulus of the fiber reinforced plastic may be lowered. is there. However, if the basis weight is smaller than 1 g / m ² , the amount of the binder composition between layers is small, and the post-impact compressive strength of the fiber reinforced plastic may be insufficient.

  The preparation method of the binder composition of the present invention is not particularly limited, and various known methods can be used. The most economical method is a method of kneading each component at about 150 to 240 ° 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. Further, a method is also possible in which the binder composition is once dissolved in a solvent to prepare a solution, and then the solvent is removed. Furthermore, a method is also possible in which an organic solvent solution is dispersed in water to form an emulsion, the emulsion is heated to volatilize the solvent to form a dispersion, and then filtered to extract the particles.

  The binder composition obtained by the above method is preferably in a state where the component [A], the component [B] and the component [C] are uniformly dissolved. Here, the uniformly dissolved state is a state in which no separated solid phase exists in the continuous layer in observation at a magnification of 50 times using a laser microscope.

  In addition, the binder composition of the present invention has good storage stability. In general, it is known that when an additive such as a plasticizer is added to a thermoplastic resin, the additive is separated. The binder composition of the present invention comprises component [B] and component during storage by blending component [A], component [B] and component [C] in the range of the blending amounts described above. The separation phenomenon of [C] from the binder composition was suppressed.

  Here, the storage stability can be evaluated by the following method. Specifically, a test piece having a thickness of 2 mm, a length of 50 mm, and a width of 50 mm was cut out from the binder composition and adjusted to a temperature of 70 ° C. and a humidity of 95% RH (for example, EC-35LHPS, manufactured by Hitachi Appliances, Inc.). The sample is allowed to stand for 7 days and then observed using a laser microscope (for example, VK-9510, manufactured by Keyence Corporation) at a magnification of 50 times.

  The storage conditions described above are extremely severe environments, and in the case of a composition having poor storage stability, a phenomenon that the plasticizer is separated in one day of storage is observed, but the binder composition of the present invention is a constituent element even after 7 days of storage. There is no separation of components from [B] and component [C]. Further, a more preferable condition for storage stability is that the plasticizer does not separate even after 14 days of storage under the storage conditions described above.

  In the binder composition of the present invention, when the constituent element [B] and the constituent element [C] are separated, the amount of the plasticizer compatible with the thermoplastic resin as the constituent element [A] is reduced, so that the plasticizing effect is achieved. Weakens, and as a result, the glass transition temperature of the binder increases. When the glass transition temperature of the binder rises, it becomes difficult to fuse to a reinforcing fiber substrate as a tackifier, or the deformability in the preforming process decreases, and the fiber volume of the obtained fiber composite material If the content is too low, the weight of the fiber-reinforced composite material becomes heavy. Therefore, storage stability is important as described above.

  The binder composition of the present invention is used as a reinforcing fiber substrate containing the binder composition and reinforcing fibers.

  As the reinforcing fiber, glass fiber, carbon fiber, aramid fiber or the like can be used. Among these, carbon fiber is preferably used from the viewpoint of obtaining a fiber-reinforced composite material that is particularly lightweight and excellent in mechanical properties such as strength and elastic modulus.

  Examples of carbon fibers include acrylic, pitch, and rayon carbon fibers. Among them, acrylic carbon fibers having high tensile strength 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 carbon fiber used in the present invention 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. Here, the tensile elastic modulus of the carbon fiber is measured according to JIS R7601-2006.

  Reinforcing fibers are used as a sheet-like reinforcing fiber substrate by combining the reinforcing fibers alone or in combination with other chemical fibers and other chemical fibers. Such a reinforcing fiber substrate preferably has at least carbon fiber. As the reinforcing fiber base material, those in which the reinforcing fibers are aligned substantially in the same direction, woven fabric, knit, braid, mat or the like can be used. Among them, from the viewpoint of obtaining a fiber-reinforced composite material having high mechanical properties and a high fiber volume content of the reinforcing fibers, the reinforcing fibers are substantially oriented in one direction and fixed with glass fibers or chemical fibers. So-called unidirectional fabrics are preferably used.

  As a unidirectional woven fabric, for example, carbon fiber bundles are arranged parallel to each other in one direction as warps, and fiber bundles made of glass fibers or chemical fibers orthogonal to the fiber bundles are used as wefts. An auxiliary warp made of a textured fiber bundle made of a glass fiber or a chemical fiber having a fineness than a carbon fiber bundle and a warp made of a carbon fiber bundle and a carbon fiber arranged in parallel thereto, and arranged perpendicular to these Non-crimp woven fabrics, etc., which are composed of wefts of fiber bundles made of glass fibers or chemical fibers, and in which the auxiliary warp yarns and the weft yarns cross each other so that the carbon fiber bundles are integrally held to form a woven fabric, etc. .

  Here, the fineness means the weight (g) per 1000 m of the fiber bundle, and is expressed by the unit 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 above ranges, there are too many intersection points in the woven fabric, and the mechanical properties may be lowered. Conversely, if the number of carbon fiber filaments and the fineness are larger than the above ranges, the number of crossing points in the woven fabric is too small, and the morphological stability and handleability of the woven fabric may be lowered.

  In the case of a woven fabric having a plain weave structure, the carbon fiber bundle and the weft are orthogonal, so the carbon fiber bundle is bent. However, in the case of a non-crimped woven fabric, the orthogonal warp and glass fiber made of glass fiber or chemical fiber are orthogonal. Or since it is a weft which consists of chemical fibers, a carbon fiber bundle becomes 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 of the fineness of the carbon fiber bundle. 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, from the viewpoint of the form stability and production stability of the fabric, it is preferably 0.05% or more of the fineness of the carbon fiber bundle. 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 of the fineness of the carbon fiber bundle. There is no particular lower limit for the fineness of the weft, and the smaller the better, but it is preferably 0.05% or more of the fineness of the carbon fiber bundle 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 yarns of carbon fibers occurs, the portion is not impregnated with the thermosetting resin, so that it becomes a defect and there is a possibility that adhesiveness and mechanical properties are reduced. Accordingly, a non-crimp woven fabric in which the carbon fiber bundle is difficult to bend is particularly preferably used.

The content of the binder composition in the reinforcing fiber base material is preferably from 5 to 50 g / ^{m 2} in basis weight, and more preferably from 7~40g / ^{m 2.} When the content is less than 5 g / m ^2, the effect of improving toughness is reduced between layers of the obtained fiber-reinforced composite material. When the content is more than 50 g / m ² , only the interlayer is thick, and the volume content of the carbon fiber in the obtained fiber-reinforced composite material is lowered, so that it is thick to express the physical properties necessary for the member. A fiber reinforced composite material may be required, and as a result, the weight of the member may increase.

  The binder composition of the present invention may be fused to one side of the reinforcing fiber base or may be fused to both sides, and can be appropriately used. In addition, content of the binder composition in an above-described reinforcing fiber base has shown the total amount in both surfaces. As a preferred method for fusing the binder composition to the surface of the reinforcing fiber base, for example, while the binder composition is measured with an embossing roll and a doctor blade, the binder composition is naturally dropped on the surface of the reinforcing fiber base to form a vibration net. There is a method in which the binder composition and the reinforcing fiber base material are fused together by being uniformly dispersed, and then heated by passing through a far infrared heater. In addition, the binder composition is supplied to the spray nozzle with a quantitative feeder, and the binder composition is sprayed onto the surface of the reinforcing fiber base using air spray, and then heated by passing through a far-infrared heater. There is also a method of fusing the substrate and the reinforcing fiber base.

  The binder composition fused on the reinforcing fiber substrate by such a method is scattered in the form of dots, and preferably 80% by volume or more of the binder composition is exposed on the reinforcing fiber substrate. State. When the binder composition is scattered in the form of dots, it is possible to suppress a decrease in resin injection property in RTM. Further, if 80% by volume or more of the binder composition is exposed on the reinforcing fiber base material, when the fiber reinforced composite material is obtained, the binder composition works as a spacer to form an appropriate interlayer thickness, and externally Is preferable because it can efficiently absorb the impact from the interlayer.

  The reinforcing fiber substrate is laminated and used as a preform. In particular, a preform in which the binder composition is present between the layers of the reinforcing fiber base by laminating the reinforcing fiber base to which the binder composition of the present invention is applied on at least one surface is preferable. By setting it as this structure, it is because reinforcement fiber base materials can be adhere | attached with a binder composition between layers, and the form of a reinforcement fiber base material can be hold | maintained now. And since this aspect can be processed into a desired shape freely and easily, and can be laminated at any fiber axis angle in order to develop strength, structural materials such as spacecraft, aircraft, railway vehicles, automobiles, ships, etc. It can be particularly preferably used.

  As a means for obtaining a preform, for example, when the shape of the reinforcing fiber base is a three-dimensional blade, it can be used as it is as a preform. Moreover, when the shape of a reinforced fiber base material is a strand, after winding a reinforced fiber base material on a mandrel, it can be heated to bond the reinforced fiber strands together to form a preform. Furthermore, for the preform in which the binder composition is present between the layers of the reinforcing fiber base material by laminating the sheet-like reinforcing fiber base material to which the binder composition of the present invention is applied on at least one side surface, A preform can be obtained by cutting a sheet-like reinforcing fiber base to which a binder composition has been applied in advance into a predetermined shape, laminating on a mold, and applying appropriate heat and pressure. Alternatively, when forming a desired shape as a preform, a method of applying appropriate heat and pressure after alternately laminating the sheet-like reinforcing fiber fabric and applying the binder composition of the present invention is adopted. You may do it.

  In the case of producing a preform by applying pressure, the pressurizing means may be a press, or a method of bagging and sucking the inside 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 less than 60 ° C., the layers forming the preform may not be sufficiently fixed. When the heating temperature exceeds 150 ° C., the binder composition is too crushed and the thermosetting resin flows. There is a possibility that unimpregnated portions may occur in the fiber-reinforced composite material obtained by blocking the road.

  In addition to the reinforcing fiber and the binder composition of the present invention, the preform may contain a foam core, a honeycomb core, a metal part, and the like.

  In the preform of the present invention, after the preform is placed in the mold, a liquid thermosetting resin composition is injected into the mold, and the preform is impregnated with the thermosetting resin composition and cured. Thus, it can be suitably used for RTM to obtain a fiber-reinforced composite material.

  In the present invention, the mold used for the RTM method may be a closed mold made of a rigid material, or an open mold of a rigid material and a flexible film (bag) can be used. In the latter case, the reinforcing fiber substrate can be placed between an open mold of rigid material and a flexible film. As the rigid material, various existing materials such as metals such as steel and aluminum, fiber reinforced plastic (FRP), wood, and plaster are used. As the flexible film material, polyamide, polyimide, polyester, fluororesin, silicone resin, or the like is used.

  In the RTM method, when a closed mold of a rigid material is used, it is usually performed by pressurizing and clamping and injecting a liquid thermosetting resin composition 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 perform the suction and inject the epoxy resin composition only at atmospheric pressure without using any special pressurizing means. This method can be suitably used because a large member can be manufactured by providing a plurality of suction ports. In this case, the degree of vacuum is preferably −90 kPa or less. If the degree of vacuum is greater than -90 kPa, voids are generated in the fiber-reinforced composite material obtained, and the mechanical properties may deteriorate.

  In the RTM method, when an open mold of a rigid material and a flexible film are used, suction is usually performed, and a liquid thermosetting resin composition is injected only at atmospheric pressure without using a special pressurizing means. In order to achieve good impregnation by injection only at atmospheric pressure, it is effective to use a resin diffusion medium. Furthermore, it is preferable to apply a gel coat to the surface of the rigid material prior to installation of the fiber base material or preform made of reinforcing fibers.

  When a rigid material closed mold is used as the mold, the inside of the mold means a cavity formed by the closed mold, and when a rigid material open mold and a flexible film are used, The term “in the space surrounded by the open mold and the flexible film” means.

  In the present invention, a type of RTM method, for example, VaRTM method, SCRIMP (Seeman's Composite Resin Infusion Molding Process) method, evacuating a resin supply tank described in JP 2005-527410 to a pressure lower than atmospheric pressure, By using the cyclic compression and controlling the net molding pressure, a resin injection process, particularly a CAPRI (Controlled Atmospheric Pressure Resin Infusion) method, which controls the VaRTM method more appropriately, can be suitably used.

  The liquid thermosetting resin composition used in the present invention comprises a liquid resin mainly composed of monomer components and a curing agent having a function of curing the monomer components by three-dimensional crosslinking.

  As such a liquid resin, an epoxy resin is preferable because it is excellent in mechanical properties and adhesiveness with reinforcing fibers. Epoxy resins 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′-methylenedianiline, N, N, N ′, N′- Tetraglycidyl-2,2′-diethyl-4,4′-methylenedianiline, 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, phthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, vinylcyclohexene diepoxide, 3,4-epoxycyclohexanecarboxylic acid-3,4-epoxycyclohexylmethyl, Diglycidyl ether of bis-3,4-epoxycyclohexylmethyl adipate and 1,6-dihydroxynaphthalene 9,9-bis (4-hydroxyphenyl) fluorene diglycidyl ether, tris (p-hydroxyphenyl) methane triglycidyl ether, tetrakis (p-hydroxyphenyl) ethane tetraglycidyl ether, 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-methylhydantoin, 1 , 3-Diglycidyl-5,5-dimethylhydantoin, bisphenol A diglycidyl ether and tolylene isocyanate are added to obtain an oxazolidone type ester Poxy resin, phenol aralkyl type epoxy and the like can be mentioned. In particular, a trifunctional or higher functional epoxy resin is preferable because of its excellent heat resistance. N, N, N ′, N′-tetraglycidyl-4,4′-methylenedianiline is preferable because it has a high effect of improving heat resistance and is excellent in chemical resistance of a cured product. In addition, N, N, O-triglycidyl-p-aminophenol has an extremely low viscosity among epoxy resins having an effect of improving heat resistance, and thus has an effect of reducing the viscosity of the thermosetting resin composition. preferable.

  It is preferable that 40-85 mass parts of epoxy resins more than trifunctional are contained in 100 mass parts of all the epoxy resins, More preferably, it is 45-75 mass parts. By setting the content of the trifunctional or higher functional epoxy resin to 40 parts by mass or more, it is possible to increase the glass transition temperature of the obtained cured product, and thus the obtained fiber-reinforced composite material. By setting the content of the trifunctional or higher epoxy resin to 85 parts by mass or less, the fracture toughness of the cured epoxy resin can be improved.

  Further, as a preferable epoxy resin other than the tri- or higher functional epoxy resin, a bifunctional epoxy resin such as N, N-diglycidylaniline or N, N-diglycidyl-o-toluidine having a diglycidylaniline skeleton has a low viscosity. In addition, since the effect of reducing the free volume in the cured product and improving the elastic modulus is high, it can be preferably used. As for content of a bifunctional epoxy resin, 10-55 mass parts is preferable in 100 mass parts of all the epoxy resins, More preferably, it is 15-50 mass parts. By setting the content of the bifunctional epoxy resin to 10 parts by mass or more, the viscosity of the obtained thermosetting resin composition is lowered, the elastic modulus of the obtained cured product is increased, and the obtained fiber-reinforced composite material Compression characteristics can be improved. By setting the content of the bifunctional epoxy resin to 55 parts by mass or less, the heat resistance and fracture toughness of the obtained cured product can be improved.

  Curing agents that can cure these epoxy resins include aliphatic polyamines, aromatic polyamines, dicyandiamides, polycarboxylic acids, polycarboxylic acid hydrazides, acid anhydrides, polymercaptans, polyphenols, and the like compounds that undergo a quantitative reaction. , Imidazole, Lewis acid complex, and onium salts. 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 a fiber reinforced composite material is molded by RTM, aliphatic polyamines, aromatic polyamines, acid anhydrides or imidazoles are suitable as curing agents. In particular, for the purpose of producing a structural material having excellent heat resistance, aromatic polyamines are most suitable, and liquid ones are preferably used. 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 And alkyl group derivatives of diaminodiphenylmethane such as -4,4'-methylenedianiline and polyoxytetramethylene bis (p-aminobenzoate). In particular, diethyltoluenediamine having low viscosity and excellent physical properties such as glass transition temperature of the obtained cured product can be preferably used.

  The liquid aromatic polyamine can be mixed with a solid aromatic polyamine as long as no crystals are precipitated. 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, linear expansion coefficient and heat resistance due to moisture absorption. Can be preferably used since the decrease in the resistance is small. 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. In the case of mixing, it is preferable because precipitation of crystals can be further suppressed and the content of diaminodiphenylsulfone can be increased more than a mixture of a single diaminodiphenylsulfone and a liquid aromatic polyamine. The content of diaminodiphenyl sulfone is preferably 10 to 40 parts by mass and more preferably 20 to 35 parts by mass in 100 parts by mass of the wholly aromatic amine. If the content is 10 parts by mass or more, the effect of the cured product as described above can be easily obtained, and if the content is 40 parts by mass or less, it is easy to suppress the precipitation of crystals. When 3,3′-diaminodiphenylsulfone and 4,4′-diaminodiphenylsulfone are used in combination in order to suppress the precipitation of crystals, the mass 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.

  When using a polyamine curing agent, the blending amount of the epoxy resin and the curing agent is such that the active hydrogen in the curing agent is in the range of 0.7 to 1.3 with respect to one epoxy group contained in the entire epoxy resin. It is preferable that the amount be in the range of 0.8 to 1.2. Here, 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.

  When an aromatic polyamine is used as the curing agent, it is known that the aromatic polyamine generally has a slow crosslinking reaction, and therefore a curing accelerator may be added to accelerate the reaction. As the curing accelerator, for example, a curing accelerator such as a tertiary amine, a Lewis acid complex, an onium salt, an imidazole, or a phenol compound can be used.

  When manufacturing a fiber reinforced composite material using RTM, it is preferable to suppress an increase in viscosity during the injection of the liquid thermosetting resin composition. t-Butylcatechol is suitable for RTM because it has a small curing acceleration effect at a temperature (50 to 80 ° C.) at the time of injecting the resin composition and has a characteristic that the curing acceleration effect increases in a temperature range of 100 ° C. or higher.

  The content when the curing accelerator is blended is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, and still more preferably 1 to 100 parts by mass with respect to 100 parts by mass of the total epoxy resin. 2.5 parts by mass. If the content of the curing accelerator is out of this range, it is not preferable because the balance between the uncured handling time and the reaction rate at high temperature is lost.

  When the viscosity of the liquid thermosetting resin composition is measured at 70 ° C., the viscosity within 5 minutes from the start of the measurement is preferably 300 mPa · s or less, more preferably 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 'x R24) (Toki Sangyo ( Using a TVE-30H), the measurement is performed at a rotation speed of 50 rotations / minute. If the viscosity within 5 minutes from the start of measurement is higher than the above range, the impregnation property of the thermosetting resin composition may be insufficient. The lower limit of the viscosity at 70 ° C. is not particularly limited, and the lower the viscosity, the easier the injection and impregnation of the thermosetting resin composition in RTM.

  After the liquid thermosetting resin composition is injected and impregnated, heat curing is performed at a temperature in the range of 50 to 200 ° C. for a 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 temperature, the higher the heat resistance of the fiber-reinforced composite material. However, the higher the temperature, the higher the cost of equipment, heat source, etc., and the longer the occupation time of the mold, the worse the economy. Therefore, initial curing is performed at a temperature in the range of 50 to 140 ° C., preferably around 130 ° C., and after the molded product is removed from the mold, final curing is performed at a higher temperature using an apparatus such as an oven. preferable.

  When assuming a structural member for an aircraft, as a final curing condition, for example, a desired fiber-reinforced composite material is obtained by curing at a temperature in a range of 160 to 180 ° C. for a time in a range of 1 to 10 hours. Can do.

  In the fiber reinforced composite material in the present invention, the fiber volume content of the reinforcing fibers is preferably in the range of 45 to 70%, more preferably in the range of 50 to 65%, and further 55 to 60%. It is preferable to be within the range. When the fiber volume content is 45% or more, a fiber-reinforced composite material having a higher elastic modulus and excellent weight reduction effect can be obtained. When the fiber volume content is 70% or less, there is no decrease in strength due to abrasion between the reinforcing fibers, and the tensile strength. Thus, a fiber-reinforced composite material having excellent mechanical properties can be obtained.

  The fiber-reinforced composite material in which the binder composition of the present invention is present between the layers is excellent in impact resistance against external impact, and particularly has high post-impact compressive strength (CAI). In order to use such a fiber reinforced composite material as a structural member for an aircraft, the CAI is preferably 230 MPa or more, more preferably 240 MPa or more. The CAI measurement of the fiber reinforced composite material was performed according to JIS K 7089 (1996), after applying a drop weight impact of 6.76 J per 1 mm thickness of the test piece to the test piece according to JIS K 7089 (1996). I do. When the CAI is lower than 230 MPa, the laminate thickness increases 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.

  Although the present invention is particularly suitable for RTM, molding methods other than RTM can also be suitably used. For example, when the shape of the reinforcing fiber substrate of the present invention is a strand or a tape, it is suitable for a filament winding method, a pultrusion method, a prepreg method, and the like. Moreover, when the shape of the reinforcing fiber substrate of the present invention is a sheet, it is also suitable for hand lay-up method, prepreg method and the like.

  Since the binder composition of the present invention suppresses the separation of the plasticizer due to fluctuations in temperature and humidity during storage, it improves the long-term storage stability of the binder composition and the reinforcing fiber equipment using the binder composition. be able to.

  Further, the fiber reinforced composite material produced using the binder composition of the present invention is lightweight and has excellent resistance to external impact, so the fuselage, main wing, tail wing, moving blade, Aircraft members such as fairings, cowls, doors, seats and interior materials; spacecraft members such as motor cases and main wings; satellite members such as structures and antennas; automobile members such as skins, chassis, aerodynamic members and seats; It can be suitably used for many structural materials such as railway vehicle members such as 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 mass unless otherwise specified.
The binder raw materials used in the examples, the adjustment method of the binder composition, the preparation method of the carbon fiber composite material, and the measurement methods of the respective characteristics are shown below.

<Raw Material of Binder Composition> The following commercially available products were used for adjusting the binder composition.
(1) Polyamide resin of component [A] “Grillamide” (registered trademark) TR55 (amorphous polyamide having 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane skeleton, glass transition temperature of 160 ° C., (Ms Chemie Japan Co., Ltd.)
“Grillamide” (registered trademark) TR90 (amorphous polyamide having 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane skeleton, glass transition temperature of 155 ° C., manufactured by Ems Chemie Japan Co., Ltd.)
“Grillamide” (registered trademark) TR90NZ (amorphous polyamide having 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane skeleton, glass transition temperature 153 ° C., manufactured by Ems Chemie Japan Co., Ltd.)
(B) Other polyamide resin / nylon 12 (crystalline polyamide, melting point: 176 ° C., glass transition temperature: 50 ° C.)
(2) Sulfonamide compound of component [B] “NOCRACK” (registered trademark) TD (p- (p-toluenesulfonylamido) diphenylamine, R ¹ substituent: phenylaminophenyl group, melting point: 135 ° C., large (Made by Shinsei Chemical)
“Topsizer” (registered trademark) 108 (N-phenyl-p-toluenesulfonamide, substituent of R ¹ : phenyl group, melting point: 101 ° C., manufactured by Fujiamide Chemical Co., Ltd.)
(3) Sulfonamide compound of component [C] “Topsizer” (registered trademark) No. 1 S (p-toluenesulfonamide, R ² substituent: methyl group, R ³ substituent: hydrogen, melting point: 138 ° C, manufactured by Fujiamide Chemical Co., Ltd.)
· "Top sizer" (registered trademark) No. 5 (o / p-toluenesulfonamide, ^{R 2} substituents: methyl group, ^{R 3} substituents: hydrogen, melting point: 113 ° C., manufactured by Fuji Amide Chemical Co.)
“Topsizer” (registered trademark) No. 8 (N-cyclohexyl-p-toluenesulfonamide, R ² substituent: methyl group, R ³ substituent: cyclohexyl group, melting point: 84 ° C., Fujiamide Chemical Co., Ltd. ) Made)
EBSA (p-ethylbenzenesulfonamide, R ² substituent: ethyl group, R ³ substituent: hydrogen, melting point: 110 ° C., manufactured by Fujiamide Chemical Co., Ltd.)
(4) Thermoplastic elastomer (a) Thermoplastic elastomer of component [D] TPAE-8 (Polymerized fatty acid polyamide elastomer, manufactured by Fuji Kasei Kogyo Co., Ltd.)
・ "PANDEX" (registered trademark) T-1185 (urethane elastomer, manufactured by DCI Bayer Polymer Co., Ltd.)
(5) Other plasticizers “CHIMASSORB” (registered trademark) 2020FDL (hindered amine plasticizer, melting point: 133 ° C., manufactured by BASF Japan Ltd.)

<Adjustment of binder composition>
The raw material of the binder composition was kneaded at a kneading temperature of 180 to 220 ° C. using a twin screw extruder to obtain pellets. The obtained pellets were freeze pulverized with a hammer mill (PULVERIZER, manufactured by Hosokawa Micron Corporation) using liquid nitrogen to obtain a particulate binder composition.

<Measurement of plasticizer separation start time>
The raw material of the binder composition is kneaded with the above-mentioned twin screw extruder, and before the obtained polymer is cooled, it is sandwiched between upper and lower tool plates equipped with a spacer having a thickness of 2 mm, and if necessary, pressure is applied with a press machine. In addition, a plate shape with a thickness of 2 mm was formed. A test piece having a length of 50 mm and a width of 50 mm was cut out from the obtained plate-shaped binder composition, and the temperature was 70 ° C. and the relative humidity was 95% RH using a constant temperature and humidity chamber (EC-35LHPS, manufactured by Hitachi Appliances). In this environment, a measured number of sheets were put in and stored, and sampled at predetermined intervals to confirm the presence or absence of crystal (plasticizer) precipitation. The sampled binder composition was checked for the presence or absence of crystal precipitation at a magnification of 50 using a laser microscope VK-9510 manufactured by Keyence Corporation. In this measurement, the time until the crystal was precipitated was defined as the separation start time of the plasticizer of the binder composition.

<Manufacture of reinforced fiber fabric made of carbon fiber>
The reinforcing fiber fabric was produced as follows. Carbon fiber bundle “Trekka” (registered trademark) T800S-24K-10E (manufactured by Toray Industries, Inc., PAN-based carbon fiber, number of filaments: 24,000, fineness: 1,033 tex, tensile elastic modulus: 294 GPa) as warp Glass fiber bundles ECDE-75-1 / 0-1.0Z (manufactured by Nittobo Co., Ltd., number of filaments) as auxiliary warps aligned at a density of 1.8 pieces / cm, parallel to this, and alternately arranged. The unidirectional sheet-like reinforcing fiber bundle group was formed by aligning 800 pieces and fineness: 67.5 tex) at a density of 1.8 pieces / cm. 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. In addition, the fineness ratio of the weft to the carbon fiber bundle fineness of the obtained reinforcing fiber fabric was 2.2%, the fineness ratio of the auxiliary warp was 6.5%, and the basis weight of the carbon fiber was 192 g / m ² .

<Production of reinforcing fiber base>
The particulate binder composition obtained in <Preparation of Binder Composition> is applied to an embossing roll and a doctor blade on one side of the reinforcing fiber fabric obtained in <Manufacturing of a reinforcing fiber fabric comprising carbon fibers>. The sample was naturally dropped while weighed and dispersed with a basis weight of 25 g / m ² while being uniformly dispersed through a vibration net. Thereafter, the reinforcing fiber fabric was passed through a far-infrared heater under the conditions of a temperature of 160 to 210 ° C. and a speed of 0.3 m / min to fuse the binder composition, and the reinforcing fibers provided with the binder composition on both surfaces. A substrate was obtained.

<Preform production>
After cutting the obtained reinforcing fiber base into a predetermined size, the longitudinal direction of the carbon fibers of the four layers of reinforcing fiber base 1 is [+ 45 ° / 0 ° / −45 ° / 90 °]. The adjacent layers were laminated so as to be shifted by 45 degrees, and this was repeated three times to obtain a total of 12 laminated bodies. Next, the two 12-layer laminates were laminated symmetrically so that the 90-degree layers face each other to obtain a total of 24 laminates. The obtained laminate was placed on the surface of an aluminum flat mold, and the top was sealed with a bag material (polyamide film) and a sealant. After the cavity formed by the mold and the bag material was evacuated, the mold was transferred to a hot air dryer and heated at a temperature of 80 to 130 ° C. for 1 hour. Then, after cooling to 60 ° C. or lower in the atmosphere while maintaining the vacuum state of the cavity, the cavity was released to the atmosphere to obtain a preform.

<Preparation of liquid thermosetting resin composition>
The thermosetting resin composition used in the molding of the fiber reinforced composite material is a two-component amine curable epoxy resin, and was prepared as follows.

  “Araldite” (registered trademark) MY721 (manufactured by Huntsman Japan K.K., component: N, N, N ′, N′-tetraglycidyl-4,4′-methylenedianiline) 50 parts and GAN (Nippon Kayaku ( Co., Ltd., component: N, N-diglycidyl aniline) 50 parts was mixed at a temperature of 70 ° C. to obtain a main agent.

  Apart from the main agent, “jER Cure” (registered trademark) W (manufactured by Mitsubishi Chemical Corporation, component: diethyltoluenediamine) 29.3 parts, 3,3′-DAS (manufactured by Konishi Chemical Industries, Ltd., component: 3,3′-Diaminodiphenylsulfone) 6.3 parts, “Seika Cure” (registered trademark) S (manufactured by Seika Co., Ltd., component: 4,4′-diaminodiphenylsulfone) 6.3 parts at a temperature of 130 ° C. The mixture was mixed with stirring, and when solids were not present, the mixture was cooled to a temperature of 70 ° C. and 1.5 parts of DIC-TBC (manufactured by DIC Corporation, component: 4-t-butylcatechol) was added. The mixture was further mixed with stirring at a temperature of 70 ° C. until no solids existed to obtain a curing agent.

  43.4 parts of the curing agent was mixed with 100 parts of the main agent to obtain a liquid thermosetting resin composition.

<Molding of fiber reinforced composite material>
The obtained preform is placed on the surface of an aluminum flat mold, a polyester fabric subjected to a release treatment as a peel ply, and a polypropylene knit as a resin diffusion medium are placed in this order, and a bag is placed thereon. Using a material and a sealant, except for providing a resin injection port and a vacuum suction port, it was 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 agent and the curing agent obtained in <Preparation of liquid thermosetting resin composition> are mixed at a ratio of 43.4 parts of the curing agent with respect to 100 parts of the main agent to obtain a liquid thermosetting property. A resin composition was prepared. The liquid thermosetting resin composition was preheated at a temperature of 70 ° C. for 30 minutes to perform vacuum deaeration treatment.

  By setting the liquid thermosetting resin composition that has been preheated and degassed in the resin inlet of the mold, and utilizing the pressure difference between the pressure in the cavity and the atmospheric pressure in the vacuumed cavity A thermosetting resin composition was injected and impregnated into the preform. When the liquid thermosetting resin composition reached the vacuum suction port, the resin injection port was closed, and the vacuum suction port was closed after holding for another hour while continuing the suction from the vacuum suction port.

  Next, the temperature was raised to 140 ° C. at a rate of 1.5 ° C. per minute, and then precured at a temperature of 140 ° C. for 2 hours. After removing the pre-cured product from the mold and removing each auxiliary material such as peel ply, the temperature is raised to 180 ° C. in a hot air dryer at a rate of 1.5 ° C. per minute, and then at a temperature of 180 ° C. Time-cured to obtain a fiber reinforced composite material.

<Measurement of volume average particle diameter of binder composition>
The obtained binder composition was measured with a laser diffraction / scattering type particle size distribution measuring device Partica LA-950V2 (manufactured by Horiba, Ltd.) in accordance with JIS Z8825-1 (2001) at a loading count of 15 times. did.

<Measurement of glass transition temperature>
5 to 10 mg each of the amorphous polyamide which is the constituent element [A] used in the examples and the binder composition obtained in each of the examples and comparative examples was sampled, and in accordance with JIS K7121 (1987), the midpoint glass The transition temperature (T _mg ) was measured. For the measurement, a differential scanning calorimeter DSC Q2000 (manufactured by TA Instruments Inc.) was used, the number of samples was 2, and an average value was obtained.

<Measurement of volume content (Vf) of reinforcing fiber in fiber-reinforced composite material>
A sample having a mass of 0.2 to 0.5 g was cut out from the obtained fiber-reinforced composite material, and Vf was measured by the nitric acid decomposition method described in JIS K7075 (1991). The number of samples was 5, and the average value was obtained.

<Measurement of compressive strength after impact of fiber reinforced composite material>
From the obtained fiber-reinforced composite material, a rectangular test piece having a longitudinal direction of the test piece with a carbon fiber orientation angle of 0 degree and a length of 150 mm and a width of 100 mm was cut out, and at the center of the rectangular test piece, according to JIS K 7089 (1996), After applying a falling weight impact of 6.76 J per 1 mm thickness of the test piece, the residual compressive strength (CAI) was measured according to JIS K 7089 (1996). The number of samples was 5, and the average value was obtained.

<Example 1>
70 parts of “Grillamide” (registered trademark) TR55, 15 parts of “Topsizer” (registered trademark) 108 and 15 parts of “Topsizer” (registered trademark) No. 1 S were used as raw materials and the kneading temperature was 220 ° C. Preparation of Composition> A binder composition of Example 1 was obtained according to the following. The obtained binder composition had a volume average particle size of 83 μm and a glass transition temperature of 76 ° C. Moreover, the separation start time of the plasticizer was 10 days, and it was found that the long-term storage stability was excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 56%. Moreover, the compressive strength after impact was 234 MPa, and it was found that the impact resistance was excellent.

<Example 2>
Example 2 in accordance with <Preparation of Binder Composition> described above using 70 parts of “Grillamide” (registered trademark) TR90, 15 parts of “Topsizer” (registered trademark) 108 and 15 parts of EBSA at a kneading temperature of 220 ° C. A binder composition was obtained. The obtained binder composition had a volume average particle size of 83 μm and a glass transition temperature of 89 ° C. Moreover, the separation start time of the plasticizer was 10 days, and it was found that the long-term storage stability was excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 54%. Moreover, the compressive strength after impact was 240 MPa, and it was found that the impact resistance was excellent.

<Example 3>
70 parts of “Grillamide” (registered trademark) TR90NZ, 15 parts of “Topsizer” (registered trademark) 108 and 15 parts of “Topsizer” (registered trademark) No. 1 S were used as the raw materials and the kneading temperature was 220 ° C. Preparation of composition> A binder composition of Example 3 was obtained. The obtained binder composition had a volume average particle size of 81 μm and a glass transition temperature of 69 ° C. Moreover, it was found that the separation start time of the plasticizer was 7 days, and the long-term storage stability was excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 56%. Moreover, the compressive strength after impact was 245 MPa, and it was found that the impact resistance was excellent.

<Example 4>
70 parts of “Grillamide” (registered trademark) TR90NZ, 15 parts of “Nocrack” (registered trademark) TD and 15 parts of “Topsizer” (registered trademark) No. 1 S were used as the raw materials and the kneading temperature was 220 ° C. Preparation of product> The binder composition of Example 4 was obtained. The obtained binder composition had a volume average particle size of 78 μm and a glass transition temperature of 78 ° C. Further, it was found that the separation start time of the plasticizer was 14 days, and the long-term storage stability was particularly excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 56%. Moreover, the compressive strength after impact was 249 MPa, and it was found that the impact resistance was excellent.

<Example 5>
“Grill amide” (registered trademark) TR90 80 parts, “NOCRACK” (registered trademark) TD 4 parts and “Topsizer” (registered trademark) No. 1 S 16 parts as raw materials, kneading temperature 220 ° C. Preparation of product> A binder composition of Example 5 was obtained. The obtained binder composition had a volume average particle size of 86 μm and a glass transition temperature of 82 ° C. Moreover, it was found that the separation start time of the plasticizer was 7 days, and the long-term storage stability was excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 54%. Moreover, the compressive strength after impact was 265 MPa, and it was found that the impact resistance was excellent.

<Example 6>
<Ginder amide> (registered trademark) TR90 80 parts, "Nocrack" (registered trademark) TD 16 parts and "Topsizer" (registered trademark) No. 1 S 4 parts as raw materials, kneading temperature 220 ° C. Preparation of product> A binder composition of Example 6 was obtained. The obtained binder composition had a volume average particle size of 82 μm and a glass transition temperature of 103 ° C. The plasticizer separation start time was 8 days, and it was found that the plasticizer was excellent in long-term storage stability.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 53%. Moreover, the compressive strength after impact was 252 MPa, and it was found that the impact resistance was excellent.

<Example 7>
“Grill amide” (registered trademark) TR90NZ 80 parts, “NOCRACK” (registered trademark) TD 7 parts and “Topsizer” (registered trademark) No. 1 S 13 parts as raw materials, kneading temperature 220 ° C. Preparation of product> A binder composition of Example 7 was obtained. The obtained binder composition had a volume average particle size of 88 μm and a glass transition temperature of 85 ° C. The plasticizer separation start time was 8 days, and it was found that the plasticizer was excellent in long-term storage stability.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 56%. Moreover, the compressive strength after impact was 264 MPa, and it was found that the impact resistance was excellent.

<Example 8>
“Grill amide” (registered trademark) TR90NZ 80 parts, “NOCRACK” (registered trademark) TD 13 parts and “Topsizer” (registered trademark) No. 1 S 7 parts as raw materials, kneading temperature 220 ° C. Preparation of product> A binder composition of Example 8 was obtained. The obtained binder composition had a volume average particle size of 85 μm and a glass transition temperature of 98 ° C. Moreover, the separation start time of the plasticizer was 9 days, and it was found that the long-term storage stability was excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 54%. Moreover, the compressive strength after impact was 259 MPa, and it was found that the impact resistance was excellent.

<Example 9>
“Grill amide” (registered trademark) TR90NZ 80 parts, “NOCRACK” (registered trademark) TD 10 parts and “Topsizer” (registered trademark) No. 1 S 10 parts as raw materials, kneading temperature 220 ° C. Preparation of product> A binder composition of Example 9 was obtained. The obtained binder composition had a volume average particle size of 86 μm and a glass transition temperature of 88 ° C. Moreover, it was found that the separation start time of the plasticizer was 21 days or longer, and the long-term storage stability was particularly excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 55%. Moreover, the compressive strength after impact was 265 MPa, and it was found that the impact resistance was excellent.

<Example 10>
<Ginder amide> (registered trademark) TR90NZ 80 parts, "NOCRACK" (registered trademark) TD 10 parts and "Topsizer" (registered trademark) No. 8 10 parts as raw materials, kneading temperature 220 ° C. Of the binder composition of Example 10 was obtained. The obtained binder composition had a volume average particle size of 88 μm and a glass transition temperature of 84 ° C. Moreover, it was found that the separation start time of the plasticizer was 21 days or longer, and the long-term storage stability was particularly excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 54%. Moreover, the compressive strength after impact was 261 MPa, and it was found that the impact resistance was excellent.

<Example 11>
“Grillamide” (registered trademark) TR90NZ 80 parts, “NOCRACK” (registered trademark) TD 7.5 parts, “Topsizer” (registered trademark) No. 5 7.5 parts and TPAE-8 5 parts, and kneading temperature The binder composition of Example 11 was obtained at 220 ° C. according to <Preparation of Binder Composition> described above. The obtained binder composition had a volume average particle size of 93 μm and a glass transition temperature of 98 ° C. Further, it was found that the separation start time of the plasticizer was 14 days, and the long-term storage stability was particularly excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 58%. Moreover, the compressive strength after impact was 276 MPa, and it was found that the impact resistance was particularly excellent.

<Example 12>
“Grill amide” (registered trademark) TR90NZ 75 parts, “NOCRACK” (registered trademark) TD 7.5 parts, “Topsizer” (registered trademark) No. 5 7.5 parts and TPAE-8 10 parts, and kneading temperature The binder composition of Example 12 was obtained at 220 ° C. according to <Preparation of Binder Composition> described above. The obtained binder composition had a volume average particle diameter of 101 μm and a glass transition temperature of 91 ° C. Moreover, it was found that the separation start time of the plasticizer was 7 days, and it was excellent in long-term storage stability.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 58%. Further, the compressive strength after impact was 286 MPa, and it was found that the impact resistance was particularly excellent.

<Example 13>
"Grillamide" (registered trademark) TR90NZ 80 parts, "NOCRACK" (registered trademark) TD 7.5 parts, "Topsizer" (registered trademark) No. 1 S 7.5 parts and "PANDEX" (registered trademark) T-1185 A binder composition of Example 13 was obtained using 5 parts as a raw material and a kneading temperature of 220 ° C. in accordance with <Preparation of Binder Composition> described above. The obtained binder composition had a volume average particle size of 99 μm and a glass transition temperature of 96 ° C. Moreover, the separation start time of the plasticizer was 7 days, and it was found that the long-term storage stability was particularly excellent.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 57%. Moreover, the compressive strength after impact was 271 MPa, and it was found that the impact resistance was particularly excellent.

<Comparative Example 1>
80 parts of nylon 12, 10 parts of “NOCRACK” (registered trademark) TD and 10 parts of “Topsizer” (registered trademark) No. 1 S were used as raw materials at a kneading temperature of 220 ° C. according to the above-mentioned <Adjustment of Binder Composition>. The binder composition of Comparative Example 1 was obtained. The obtained binder composition had a volume average particle size of 82 μm and a plasticizer separation start time of 10 days, which proved excellent in long-term storage stability. The glass transition temperature was 40 ° C. and was found to be low.

  Next, using this binder composition, a carbon fiber composite material was prepared according to <Preparation of Reinforced Fiber Base>, <Preparation of Preform>, and <Molding of Fiber Reinforced Composite Material>. Vf of the obtained carbon fiber composite material was 58%. It was also found that the compressive strength after impact was 198 MPa, which was significantly low and insufficient. The binder composition used here did not contain the component [A].

<Comparative example 2>
Binder composition of Comparative Example 2 using 70 parts of “Grillamide” (registered trademark) TR90NZ and 30 parts of “Topsizer” (registered trademark) No. 5 at a kneading temperature of 220 ° C. according to <Preparation of Binder Composition> described above. I got a thing. The obtained binder composition had a volume average particle size of 85 μm and a glass transition temperature of 70 ° C. It was also found that the plasticizer separation start time was 5 days, which was short and insufficient.

  Next, using the binder composition of Comparative Example 2, a reinforcing fiber substrate was prepared according to the above-mentioned <Preparation of reinforcing fiber substrate>. The plasticizer was separated, but the binder was passed through a far infrared heater. The composition could be fused to the extent that it did not fall off. Using the obtained reinforcing fiber base material, a carbon fiber composite material was prepared in accordance with <Preparation of preform> and <Molding of fiber reinforced composite material> described above. Vf of the obtained carbon fiber composite material was 52%. It was also found that the compressive strength after impact was 210 MPa, which was significantly low and insufficient. The binder composition used here did not contain the component [B].

<Comparative Example 3>
70 parts of “Grillamide” (registered trademark) TR90NZ, 25 parts of “Topsizer” (registered trademark) No. 1 S and 5 parts of “CHIMASORB” (registered trademark) 2020FDL were used as the raw materials and the kneading temperature was 220 ° C. Preparation of product> A binder composition of Comparative Example 3 was obtained. The obtained binder composition had a volume average particle size of 86 μm and a glass transition temperature of 56 ° C. Further, it was found that the separation start time of the plasticizer was 2 days, which was very short and the storage stability was insufficient.

  Next, using each of these binder compositions, a reinforcing fiber substrate was prepared according to the above-mentioned <Preparation of reinforcing fiber substrate>, and the plasticizer was severely separated, and the binder composition was passed through a far-infrared heater. It was not possible to fuse and a reinforcing fiber substrate could not be obtained. The binder composition used here did not contain the component [B].

<Comparative example 4>
70 parts of “Grillamide” (registered trademark) TR90NZ, 15 parts of “Topsizer” (registered trademark) No. 1 S and 15 parts of EBSA, kneading temperature 220 ° C., comparison according to the above-mentioned <Adjustment of binder composition> The binder composition of Example 4 was obtained. The obtained binder composition had a volume average particle size of 85 μm and a glass transition temperature of 71 ° C. Further, it was found that the separation start time of the plasticizer was 2 days, which was very short and the storage stability was insufficient.

  Next, using this binder composition, a reinforcing fiber substrate was prepared according to <Preparation of Reinforcing Fiber Base>, and the binder composition was fused by passing through a far-infrared heater with severe separation of the plasticizer. The reinforcing fiber base material could not be obtained. The binder composition used here did not contain the component [B].

<Comparative Example 5>
The binder of Comparative Example 5 was prepared by using 70 parts of “Grillamide” (registered trademark) TR90 and 30 parts of “Topsizer” (registered trademark) No. 1 S at a kneading temperature of 220 ° C. according to <Preparation of Binder Composition> described above. A composition was obtained. The obtained binder composition had a volume average particle size of 85 μm and a glass transition temperature of 64 ° C. Moreover, it was found that the separation start time of the plasticizer was 1 day, which was very short and the storage stability was insufficient.

  Next, using this binder composition, a reinforcing fiber substrate was prepared according to <Preparation of Reinforcing Fiber Base>, and the binder composition was fused by passing through a far-infrared heater with severe separation of the plasticizer. The reinforcing fiber base material could not be obtained. The binder composition used here did not contain the component [B].

<Comparative Example 6>
A binder composition of Comparative Example 6 was obtained by using 60 parts of “Grillamide” (registered trademark) TR90 and 40 parts of EBSA at a kneading temperature of 220 ° C. according to the above-mentioned <Preparation of Binder Composition>. The obtained binder composition had a volume average particle diameter of 83 μm and a glass transition temperature of 65 ° C. Further, it was found that the separation start time of the plasticizer was 4 days, which was very short and the storage stability was insufficient.

  Next, using this binder composition, a reinforcing fiber substrate was prepared according to <Preparation of Reinforcing Fiber Base>, and the binder composition was fused by passing through a far-infrared heater with severe separation of the plasticizer. The reinforcing fiber base material could not be obtained. The binder composition used here did not contain the component [B].

<Comparative Example 7>
70 parts of “Grillamide” (registered trademark) TR90NZ and 30 parts of “Nocrack” (registered trademark) TD were used as raw materials, the kneading temperature was 220 ° C., and the binder composition of Comparative Example 7 was prepared according to the above-mentioned <Preparation of Binder Composition>. Obtained. The obtained binder composition had a volume average particle size of 88 μm and a glass transition temperature of 92 ° C. Further, it was found that the separation start time of the plasticizer was 3 days, which was very short and the storage stability was insufficient.

  Next, using this binder composition, a reinforcing fiber substrate was prepared according to <Preparation of Reinforcing Fiber Base>, and the binder composition was fused by passing through a far-infrared heater with severe separation of the plasticizer. The reinforcing fiber base material could not be obtained. The binder composition used here did not contain the constituent element [C].

<Comparative Example 8>
The binder composition of Comparative Example 8 was prepared by using 80 parts of “Grillamide” (registered trademark) TR90NZ and 20 parts of “Topsizer” (registered trademark) 108 at a kneading temperature of 220 ° C. according to the above-described <Preparation of Binder Composition>. Got. The obtained binder composition had a volume average particle size of 89 μm and a glass transition temperature of 78 ° C. Further, it was found that the separation start time of the plasticizer was 5 days, which was very short and the storage stability was insufficient.

  Next, using this binder composition, a reinforcing fiber substrate was prepared according to <Preparation of Reinforcing Fiber Base>, and the binder composition was fused by passing through a far-infrared heater with severe separation of the plasticizer. The reinforcing fiber base material could not be obtained. The binder composition used here did not contain the constituent element [C].

<Comparative Example 9>

70 parts of “Grillamide” (registered trademark) TR90NZ, 10 parts of “Topsizer” (registered trademark) 108 and 10 parts of “CHIMASSORB” (registered trademark) 2020FDL were used as raw materials at a kneading temperature of 220 ° C. The binder composition of Comparative Example 9 was obtained according to Preparation>. The obtained binder composition had a volume average particle diameter of 82 μm and a glass transition temperature of 66 ° C. Further, it was found that the separation start time of the plasticizer was 6 days, which was very short and the storage stability was insufficient.

  Next, using this binder composition, a reinforcing fiber substrate was prepared according to <Preparation of Reinforcing Fiber Base>, and the binder composition was fused by passing through a far-infrared heater with severe separation of the plasticizer. The reinforcing fiber base material could not be obtained. The binder composition used here did not contain the constituent element [C].

  By using the binder composition of the present invention, it is possible to fix the form of a preform in which reinforcing fiber base materials are laminated. The fiber reinforced composite material molded by RTM using the preform has excellent impact resistance against external impacts and has high post-impact compressive strength (CAI). Therefore, aircraft members, spacecraft members, automobile members It can be suitably used for structural members such as ship members.

Claims (10)

A binder composition comprising the following component [A], component [B] and component [C].
Component [A]: Amorphous polyamide component having a dicyclohexylmethane skeleton in the molecule and a glass transition temperature of 140 ° C. or higher [B]: A sulfonamide compound represented by the following formula (I)

(In formula (I), R ¹ is a substituent having 1 to 3 aromatic rings.)
Component [C]: a sulfonamide compound represented by the following formula (II)

(In formula (II), R ² and R ³ are each a substituent selected from hydrogen, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group, and a halogen group.) The binder composition according to claim 1, wherein the dicyclohexylmethane skeleton in the component [A] is a 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane skeleton. The component [B] and the component [C] are contained in an amount of 11 to 67 parts by mass with respect to the component [A] 100 parts by mass, and the blending amount of the component [B] and the component [C] The binder composition according to claim 1, wherein the ratio is 1: 1 to 0.5: 1 and the glass transition temperature is 40 to 110 ° C. 3. The binder composition according to any one of claims 1 to 3, further comprising a thermoplastic elastomer as the constituent element [D]. The binder composition according to claim 4, wherein the thermoplastic elastomer is a polyamide elastomer. The reinforcing fiber base material which provided the binder composition in any one of Claims 1-5 to the at least single side | surface. The reinforcing fiber base is a warp made of a carbon fiber bundle, an auxiliary warp of a fiber bundle made of glass fiber or chemical fiber arranged parallel to the fiber, and a weft made of glass fiber or chemical fiber arranged so as to be orthogonal thereto And the auxiliary warp and the weft intersect with each other so that the carbon fiber bundle is integrally held to form a woven fabric, and the binder composition has a basis weight of 5 to 50 g / m ^2. The reinforcing fiber base material according to claim 6, which is applied to both sides of the reinforcing fiber base material with a content of. A preform in which the reinforcing fiber base material according to claim 6 or 7 is laminated and the binder composition is present between layers of the reinforcing fiber base material. A fiber-reinforced composite material comprising the preform according to claim 8 and a cured product of a thermosetting resin composition. The preform according to claim 8 is installed in a cavity formed by a rigid open mold and a flexible film, the cavity is sucked by a vacuum pump, and the cavity is formed from the injection port by a differential pressure from the atmospheric pressure. A method for producing a fiber-reinforced composite material, comprising the steps of injecting a liquid thermosetting resin composition into the interior and impregnating the preform and then heat-curing the liquid thermosetting resin composition.