JP6917485B2 - A liquid composition for a fiber-reinforced plastic intermediate base material, a fiber-reinforced plastic intermediate base material, and a method for producing the fiber-reinforced plastic intermediate base material. - Google Patents

Description

The present invention relates to a liquid composition for a fiber reinforced plastic intermediate base material, a fiber reinforced plastic intermediate base material, and a method for producing the fiber reinforced plastic intermediate base material, and the liquid composition for a fiber reinforced plastic intermediate base material having particularly excellent impregnation property. , A fiber-reinforced plastic intermediate base material, and a method for producing the fiber-reinforced plastic intermediate base material.

Fiber reinforced plastic (FRP) is used for various structural members because it is lightweight and has high strength. These fields are diverse, such as housing equipment, automobiles, ships, civil engineering, and sports equipment, but in recent years, the use of FRP has been increasing especially in the fields of automobiles and transportation-related equipment that require weight reduction.

Resin and fiber are used for the production of FRP, but the method of molding using liquid resin and fiber (or woven fabric) and the intermediate base material (SMC (Sheet molding compound), prepreg) by impregnating the fiber with resin in advance. There is a way to use. As a method of molding using an intermediate base material, there are autoclave molding, sheet winding molding, oven molding, press molding and the like. In these moldings, the intermediate base material is cut, laminated to a target thickness, and cured by applying heat.

For example, a fiber-reinforced composite material characterized in that it is formed by curing an intermediate base material for a fiber-reinforced composite material is known (Patent Document 1).

Japanese Unexamined Patent Publication No. 11-302507

However, as the method for producing the above-mentioned intermediate base material, a method of hot-melting a highly viscous semi-solid resin and impregnating the fibers at a high temperature, or a method of diluting a highly viscous semi-solid resin with a solvent and impregnating at room temperature. There are a method of removing the solvent by allowing the solvent to be removed, and a method of adding a thickener to a resin in which an oligomer is dissolved in a reactive diluent and impregnating the resin at room temperature to chemically thicken the resin. However, for example, the hot melt method has a problem in impregnation property due to its high viscosity, and the solvent method tends to leave the solvent inside when the solvent is removed. Therefore, the intermediate base material having a particularly large weight per unit area. In many cases, voids are generated during molding. Further, in the method using a resin in which an oligomer is dissolved in a reactive diluent, the amount of the reactive diluent can be increased to reduce the viscosity at the time of impregnation, but the curing shrinkage becomes large, so that the dimensional stability is large. There is a problem that high FRP cannot be obtained.

Therefore, an object of the present invention is to provide a liquid composition for a fiber reinforced plastic intermediate base material which can solve the above problems and suppress voids as much as possible and which gives excellent FRP mechanical properties.

As a result of repeated studies on the composition for an intermediate base material from various viewpoints, the present inventor has come up with the liquid composition for a fiber reinforced plastic intermediate base material of the present invention.

That is, the liquid composition for a fiber-reinforced plastic intermediate base material of the present invention is a liquid composition for a matrix in a fiber-reinforced plastic intermediate base material obtained by blending the following (A) and (B), and is a fiber or a woven fabric. It is a liquid composition for forming an epoxy acrylate through a step of aging in a state of being impregnated with.
A composition (A) containing a compound (a1) having two or more epoxy groups, a composition (B) containing the following (b1) and the following (b2) as essential components.
(B1) Unsaturated group-containing monocarboxylic acid (b2) Polymerization inhibitor

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the polymerization initiator (C) and / or the esterification catalyst (D) are further added to the composition (A) and / or. It is characterized in that it is blended in (B).

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the molar ratio of epoxy reactive groups in the composition (B) to the number of moles of epoxy groups in the composition (A). It is characterized in that (B / A) is 0.8 to 1.2.

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the polymerizable monomer (E) in which the composition (A) and / or (B) does not contain an epoxy reactive group is used. It is characterized by including.

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the content of the polymerizable monomer (E) is 0 with respect to the total weight of the compositions (A) and (B). It is characterized by being ~ 40% by weight.

Further, the fiber-reinforced plastic intermediate base material of the present invention is characterized in that the fiber material is impregnated with the liquid composition of the present invention.

Further, the method for producing a fiber reinforced plastic intermediate base material of the present invention includes a step of impregnating a fiber material with an arbitrary composition of the liquid composition of the present invention and aging the fiber reinforced plastic intermediate base material obtained by the impregnation. It is characterized by including a step of making the fiber.

Further, in a preferred embodiment of the method for producing a fiber-reinforced plastic intermediate base material of the present invention, the aging temperature is 30 to 90 ° C.

Further, the fiber-reinforced composite material of the present invention is characterized in that the reinforced plastic intermediate base material of the present invention is cured.

According to the liquid composition for a fiber-reinforced plastic intermediate base material of the present invention, it is possible to provide an intermediate base material having excellent impregnation property into the base material, small shrinkage during curing, and excellent dimensional stability. It has the advantageous effect of being. Further, according to the present invention, the obtained intermediate base material has excellent mechanical characteristics, and has an advantageous effect that it is possible to provide a highly reliable composite material having almost no voids or unimpregnated portions. Further, the intermediate base material of the present invention also has an advantageous effect of being excellent in curability and storability.

Further, according to the present invention, the present invention using a liquid composition having a low viscosity and excellent impregnation property has an advantageous effect that an intermediate base material having a large unit area weight can be produced. Further, according to the present invention, with respect to an intermediate base material having a large unit area weight, it is possible to provide a high-strength FRP with as few voids as possible by reducing the number of laminations and an FRP having excellent dimensional stability. Play.

Embodiments of the present invention will be described in detail below, but the present invention is not limited to the following description as long as the gist of the present invention is not exceeded. In the present invention, "(meth) acrylate" means "acrylate" and "methacrylate". Similarly, "(meth) acrylic acid" indicates "acrylic acid" and "methacrylic acid".

That is, the liquid composition for a fiber-reinforced plastic intermediate base material of the present invention is a liquid composition for a fiber-reinforced plastic intermediate base material obtained by blending the following (A) and (B).
A composition (A) containing a compound (a1) having two or more epoxy groups, a composition (B) containing the following (b1) as an essential component and further containing (b2).
(B1) Unsaturated group-containing monocarboxylic acid (b2) Polymerization inhibitor

First, the composition (A) will be described. The composition (A) is a composition containing a compound (a1) having two or more epoxy groups. Examples of the compound (a1) having two or more epoxy groups applicable to the present invention include polyhydric phenols such as bisphenol A, bisphenol F, bisphenol AD, catechol and resorcinol, and polyhydric alcohols such as glycerin and polyethylene glycol. Polyglycidyl ether obtained by reacting with epichlorohydrin, p-hydroxybenzoic acid, glycidyl ether ester obtained by reacting hydroxycarboxylic acid such as β-hydroxynaphthoic acid with epichlorohydrin, phthalic acid. Polyglycidyl ester obtained by reacting a polycarboxylic acid such as terephthalic acid with epichlorohydrin, as well as epoxidized phenol novolac, epoxidized cresol novolac, epoxidized polyolefin, cyclic aliphatic epoxy, and other urethane modifications. Examples include, but are not limited to, epoxy and the like. These compounds having an epoxy group can be used alone or in combination of two or more.

Among these, the compound (a1) having an epoxy group includes a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a phenol novolac type epoxy resin, and a biphenyl aralkyl type from the viewpoint of maintaining high heat resistance and low moisture permeability. At least one selected from the group consisting of an epoxy resin, a phenol aralkyl type epoxy resin, an aromatic glycidylamine type epoxy resin, and an epoxy resin having a dicyclopentadiene structure is preferable. The epoxy resin may be liquid or solid, and both liquid resin and solid resin may be used.

The epoxy equivalent of the epoxy resin is, for example, 50 to 1000 g / eq, preferably 100 to 500 g / eq, and more preferably 100 to 300 g / eq.

Next, the composition (B) will be described. The composition (B) is a composition containing an unsaturated group-containing monocarboxylic acid (b1) and a polymerization inhibitor (b2) in an arbitrary ratio. The composition (B) contains an unsaturated group-containing monocarboxylic acid (b1) as an essential component, and a polymerization inhibitor (b2) is added as necessary. The unsaturated group-containing monocarboxylic acid (b1) blended in the composition (B) is preferably liquid. The unsaturated group-containing monocarboxylic acid (b1) is a (meth) acrylic acid containing an unsaturated group, and is, for example, a monocarboxylic acid such as (meth) acrylic acid, crotonic acid, cinnamic acid, and sorbic acid. For example, a reaction product of dibasic acid anhydride and an alcohol having at least one unsaturated group in the molecule can be mentioned. Examples of the dibasic acid anhydride include maleic anhydride, succinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride and the like. These unsaturated group-containing monocarboxylic acids (b1) can be used alone or in combination of two or more. Among these unsaturated group-containing monocarboxylic acids (b1), monocarboxylic acid, more preferably (meth) acrylic acid, and further preferably methacrylic acid, from the viewpoint of the viscosity of the liquid composition and the mechanical properties of the cured product. Is preferable.

As the polymerization inhibitor (b2), for example, known polyhydric phenolic polymerization inhibitors such as hydroquinone, parabenzoquinone, methylhydroquinone, and trimethylhydroquinone can be used.

Next, a polymerization initiator (C), an esterification catalyst (D), and a polymerizable monomer (E) containing no epoxy-reactive group will be described. Each of these components can be incorporated into either the composition (A) or (B). The polymerization initiator (C), the esterification catalyst (D), and the polymerizable monomer (E) containing no epoxy reactive group are blended as necessary.

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the polymerization initiator (C) and / or the esterification catalyst (D) are further added to the composition (A) and / or. It is characterized in that it is blended in (B).

Examples of the polymerization initiator (C) include organic peroxides, such as ketone peroxides such as methyl ethyl ketone peroxide and acetylacetone peroxide, diacyl peroxides such as benzoyl peroxide, and t-butyl peroxybenzoate. Peroxyester type, hydroperoxide type such as cumene hydroperoxide, dialkyl peroxide type such as dicumyl peroxide, peroxydicarbonate type such as bis (4-terrary butyroylhexyl) peroxydicarbonate, etc. Can be mentioned.

Further, when imparting photocurability to the intermediate substrate, an initiator for photocuring can be used, for example, an acetophenone-based substance such as acetophenone, p-dimethylaminoacetophenone, p-dimethylaminopropiophenone, etc. Aminobenzophenone such as α-alkylaminobenzophenone, benzophenone, benzophenone such as 2-chlorobenzophenone, benzoinether such as benzoin methyl ether, benzyl acetal such as benzyl dimethyl ketal, 2-ethylanthraquinone, octamethyl anthraquinone, etc. Examples thereof include anthraquinone-based, organic peroxides such as cumempaoxide, thiol compounds such as 2-mercaptobenzoimider, and o-acyloxime-based such as acetophenone o-benzoyloxime.

These can be appropriately selected from the aging temperature, molding temperature, and storage temperature of the intermediate base material, and can be used alone or in combination of two or more. The amount of the polymerization initiator (C) added is 0.05 to 5 parts by weight with respect to 100 parts by weight of the total liquid composition of the components (A) + (B) from the viewpoint of obtaining good curability. .. The polymerization initiator (C) can be blended with the composition (B), but since the composition (B) contains a compound having an unsaturated group-containing monocarboxylic acid, it can be used as the composition (B). In consideration of the storage stability of the above, it is preferable to add it to the composition (A).

Moreover, it is preferable to use a known catalyst as the esterification catalyst (D). Examples of such a catalyst include tertiary amines such as triethylamine and dimethylbenzylamine, quaternary ammonium salts, imidazole derivatives such as imidazole and 2-methylimidazole, organic phosphorus compounds such as triphenylphosphine, and triphenylantimon. Organic antimony compounds can be mentioned. In these catalysts, the intermediate substrate is sufficiently aged with respect to a total of 100 parts by weight of the compound (a1) having at least two or more epoxy groups in one molecule and the unsaturated group-containing monocarboxylic acid (b1). From the viewpoint of realizing that, it can be used in the range of 0.01 to 10 parts by weight.

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, from the viewpoint of obtaining good mechanical strength, the composition (with respect to the number of moles of epoxy groups in the composition (A)) The epoxy reactive group molar ratio (B / A) in B) is 0.8 to 1.2.

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the polymerizable monomer (E) in which the composition (A) and / or (B) does not contain an epoxy reactive group is used. It is characterized by including. The polymerizable monomer (E) containing no epoxy-reactive group is preferably one that does not react with the epoxy group at room temperature, and a vinyl monomer, a monofunctional (meth) acrylic acid ester, or a polyfunctional (meth) acrylic acid ester is preferable. Can be mentioned. If a polymerizable monomer that reacts with an epoxy group is blended, there is a risk that the viscosity will increase due to the reaction during storage, resulting in poor workability or insufficient mechanical properties.

Examples of the vinyl monomer include styrene, vinyl toluene, α-methylstyrene, vinyl acetate and the like, and examples of the monofunctional (meth) acrylic acid ester include methyl methacrylate, benzyl (meth) acrylate and n-butyl (meth). ) Acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) ) Acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, norbornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl Examples of the polyfunctional (meth) acrylic acid ester such as oxyethyl (meth) acrylate include ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 1,3-propanediol di (meth) acrylate, and 1, 4-Butandiol di (meth) acrylate, neopentyl glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tripropylene di (meth) acrylate, norbornene dimethanol di (meth) acrylate, tricyclodecane dimethanol di ( Meta) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, propylene oxide-added bisphenol A di (meth) acrylate, trimethylolpropanthry (meth) acrylate, tris (2- (meth) acryloyloxyethyl) isocyanurate, etc. Can be mentioned. These polymerizable monomers (E) can be used alone or in combination of two or more. Diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene di (meth) acrylate, benzyl methacrylate, dicyclopentenyl from the viewpoint of tackiness and odor as an intermediate base material and mechanical properties of the cured product. It is preferable to apply a meta) acrylate, an ethylene oxide-added bisphenol A di (meth) acrylate, a tricyclodecanedimethanol di (meth) acrylate, and a propylene oxide-added bisphenol A di (meth) acrylate.

Further, in a preferred embodiment of the liquid composition for a fiber reinforced plastic intermediate base material of the present invention, the content of the polymerizable monomer (E) is 0 with respect to the total weight of the compositions (A) and (B). It is characterized by being ~ 40% by weight. That is, the blending amount of the polymerizable monomer (E) is 0 to 0 in the liquid composition according to the epoxy (meth) acrylate obtained by aging with respect to the viscosity characteristics and tackiness targeted as the intermediate base material. It can be adjusted in the range of 40% by weight. From the viewpoint of reducing the curing shrinkage of the intermediate base material, 0 to 30% by weight is preferable.

The viscosity of the liquid composition of the present invention is preferably 0.1 Pa · s to 5 Pa · s at 25 to 80 ° C. when the compositions (A) and (B) are mixed. If the viscosity exceeds 5 Pa · s, the base material may be impregnated poorly depending on the conditions, and an unimpregnated portion may be formed, which is not preferable.

The liquid composition of the present invention changes to an epoxy (meth) acrylate by aging, and the ethylenically unsaturated group equivalent of the epoxy (meth) acrylate is not particularly limited, but is preferably less than 1000 g / eq. If it is 1000 g / eq or more, the balance of mechanical properties (flexural strength, tensile strength, compressive strength, interlayer shear strength) becomes poor, and the heat resistance of the molded product may be lowered.

In the present invention, since it changes to epoxy (meth) acrylate, it is possible to provide a molded product having excellent chemical resistance. The type of chemical having resistance is not particularly limited, and examples thereof include water, chemicals (acids, alkalis, etc.), and solvents (ethanol, etc.). These have different chemical resistance depending on the concentration and temperature.

Inorganic particles and rubber particles may be added to the liquid composition of the present invention for the purpose of adjusting viscoelasticity and improving mechanical properties. Examples of the inorganic particles include, but are not limited to, calcium carbonate, alumina, talc, titanium oxide, silica and the like. The rubber component is not particularly limited, and examples thereof include crosslinked rubber particles and core-shell rubber particles in which the rubber component is wrapped in a crosslinked polymer.

Further, carbon nanotubes can be added to the liquid composition of the present invention in order to further improve the mechanical strength and impact resistance of FRP.

Further, a low shrinkage agent, an internal mold release agent, a component dispersant and the like can be added to the liquid composition of the present invention, if necessary. These formulations are preferably liquid from the viewpoint of solubility, but may be solid as long as they are dissolved in the composition by applying heat.

Further, the fiber-reinforced plastic intermediate base material of the present invention is characterized in that the fiber material is impregnated with the liquid composition of the present invention.

Examples of the fiber used for the intermediate base material of the present invention include, but are not limited to, carbon fiber, glass fiber, aramid fiber, zylon fiber, boron fiber, basalt fiber, and cellulose. The reinforcing fiber content is preferably 10 to 90% by weight, preferably 30 to 80% by weight from the viewpoint of mechanical properties and moldability. The surface treatment agent and shape (unidirectional, cloth, NCF, non-woven fabric, etc.) of the reinforcing fiber are not limited. It is also possible to sandwich the core material between the fiber base material and the fiber base material. Examples of the core material include foamed non-woven fabric and honeycomb core mat.

Further, the method for producing a fiber reinforced plastic intermediate base material of the present invention includes a step of impregnating a fiber material with an arbitrary composition of the liquid composition of the present invention and aging the fiber reinforced plastic intermediate base material obtained by the impregnation. It is characterized by including a step of making the fiber. In the present invention, the liquid composition can be impregnated into the fiber material with an arbitrary composition at a temperature of, for example, 10 to 60 ° C., although not particularly limited. Further, in the present invention, if necessary, the fiber material may be further sandwiched between films and the fiber material may be impregnated with the liquid composition by roller pressure to form a roll or a binding. Then, the fiber-reinforced plastic intermediate base material obtained by impregnation can be aged. That is, in the present invention, it is possible to form an epoxy acrylate in a state where the liquid composition is impregnated in the fiber or the woven fabric during the aging. In the past, epoxy acrylate was once formed and then impregnated into fibers and the like. Surprisingly, the liquid composition of the present invention is aged in a state of being impregnated with fibers or woven fabrics. The present inventors have found that an epoxy acrylate is formed through the process. This makes it possible to bond the liquid composition and the fiber more firmly in the present invention, and as will be clear from the examples described later, better impregnation, curability, mechanical properties and the like can be obtained. It has the advantageous effect of being able to exert it.

In a preferred embodiment, the aging temperature can be 30 to 90 ° C. from the viewpoint of promoting epoxy acrylate formation and suppressing the radical polymerization reaction. First, the liquid composition can be coated on a film, the fibers or woven fabric can be placed on the coated surface, sandwiched between the films, and pressure is applied by a roller to impregnate the fibers or woven fabric with the liquid composition. It is preferable to have a breakwater-shaped jig in order to maintain a constant width of the coated material from the coating site until the coated material comes into contact with the fiber or the woven fabric. Alternatively, the liquid composition can be dropped or sprayed onto the fiber or woven fabric, further sandwiched between films, and pressure is applied by a roller to impregnate the fiber or woven fabric with the liquid composition. Those impregnated by these methods can be rolled or spliced and aged in a furnace (30 to 90 ° C.).

Further, the fiber-reinforced composite material of the present invention is characterized in that the reinforced plastic intermediate base material of the present invention is cured.

The cured product of the intermediate base material of the present invention is obtained by heat-curing by applying heat and pressure. Molding methods that apply heat and pressure include autoclave molding, oven molding, sheet winding molding, press molding, and the like. Although it depends on the type of the polymerization initiator in the liquid composition, the molding temperature is preferably 70 to 180 ° C., preferably 100 to 150 ° C., and the time is preferably 3 to 60 minutes, and the pressure is preferably 1 to 15 MPa.

Hereinafter, one embodiment of the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. In this embodiment, "parts" are parts by weight unless otherwise specified. In the examples, prepreg and C-SMC (carbon SMC (Sheet Molding Compound)) were prepared as examples of the intermediate base material.

Comparative synthesis example 1
(Synthesis of epoxy (meth) acrylate resin (EA-1))
539.2 parts of bisphenol A type epoxy compound with epoxy equivalent of 430 g / eq, 108.3 parts of methacrylic acid, triphenylphosphine 1. 95 parts and 0.24 parts of hydroquinone were charged, kept under air (0.2 L / min) and at a temperature of 110 to 120 ° C., and reacted for 10 hours. Then, it was diluted with 350.0 parts of styrene to obtain an epoxy acrylate resin having an acid value of 6.1 mg / KOH.

Comparative synthesis example 2
(Synthesis of epoxy (meth) acrylate resin (EA-2))
689.9 parts of bisphenol A type epoxy compound (JER "# 1001"), 127.6 parts of methacrylic acid, 2-methylimidazole in a five-necked flask equipped with a thermometer, a stirrer, a gas introduction tube, and a reflux condenser. 1.6 parts and 0.8 parts of monomethyl ether hydroquinone were charged, kept under air flow (0.2 L / min) and at a temperature of 110 to 120 ° C., and reacted for 10 hours. Then, it was diluted with 180.0 parts of diethylene glycol dimethacrylate (NK ester 2G, manufactured by Shin-Nakamura Chemical Co., Ltd.) to obtain an epoxy acrylate resin having an acid value of 2.4 mg / KOH.

[Preparation of liquid composition]
Composition A and composition B were prepared, respectively.

<Preparation of Composition A>
Preparation of liquid composition A (x-1) (for preparation of composition (C-1) used in Examples 1 and 9)
816.9 parts of bisphenol A type epoxy compound (EP-190 manufactured by DIC), 162.8 parts of diethylene glycol dimethacrylate (NK ester 2G manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate system manufactured by Nichiyu Co., Ltd.) in a container. 20.3 parts of (organic peroxide) was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-1).

Preparation of liquid composition A (x-2) (for preparation of composition (C-2) used in Examples 2 and 10)
In a container, 777.5 parts of bisphenol A type epoxy compound (JER "# 1001"), 205.4 parts of diethylene glycol dimethacrylate (NK ester 2G, manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate-based organic manufactured by Nichiyu Co., Ltd.) 17.1 part of peroxide) was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-2).

Preparation of liquid composition A (x-3) (for preparation of composition (C-3) used in Examples 3 and 11)
719.8 parts of bisphenol A type epoxy compound (JER "# 1002"), 263.7 parts of diethylene glycol dimethacrylate (NK ester 2G, manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate-based organic manufactured by Nikko Co., Ltd.) in a container. 16.5 parts of peroxide was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-3).

Preparation of liquid composition A (x-4) (for preparation of composition (C-4) used in Examples 4 and 12)
In a container, 736.3 parts of cresol novolac type epoxy resin (EPICLON N-690 manufactured by DIC), 244.4 parts of diethylene glycol dimethacrylate (NK ester 2G manufactured by Shin-Nakamura Chemical Co., Ltd.), and perbutyl E (monooxycarbonate manufactured by Nichiyu Co., Ltd.). 19.3 parts of the system organic peroxide) was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-4).

Preparation of liquid composition A (x-5) (for preparation of composition (C-5) used in Examples 5 and 13)
824.4 parts of bisphenol A type epoxy compound (EP-190 manufactured by DIC), 154.5 parts of diethylene glycol dimethacrylate (NK ester 2G manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate type manufactured by Nichiyu Co., Ltd.) in a container. 21.1 parts of (organic peroxide) was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-5).

Preparation of liquid composition A (x-6) (for preparation of composition (C-6) used in Examples 6 and 14)
829.5 parts of bisphenol A type epoxy compound (EP-190 manufactured by DIC), 148.3 parts of diethylene glycol dimethacrylate (NK ester 2G manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate system manufactured by Nichiyu Co., Ltd.) in a container. 22.2 parts of (organic peroxide) was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-6).

Preparation of liquid composition A (x-7) (for preparation of composition (C-7) used in Examples 7 and 15)
383.0 parts of bisphenol A type epoxy compound (EP-190 manufactured by DIC), 142.6 parts of diethylene glycol dimethacrylate (NK ester 2G manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate system manufactured by Nichiyu Co., Ltd.) in a container. 19.4 parts of (organic peroxide) was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-7).

Preparation of liquid composition A (x-8) (for preparation of composition (C-8) used in Examples 8 and 16)
In a container, 695.3 parts of bisphenol A type epoxy compound (JER "# 1004"), 288.7 parts of diethylene glycol dimethacrylate (NK ester 2G, manufactured by Shin-Nakamura Chemical Co., Ltd.), perbutyl E (monooxycarbonate-based organic manufactured by Nikko Co., Ltd.) 16.0 parts of peroxide was blended and stirred at room temperature until a uniform solution was obtained to obtain composition A (x-8).

<Preparation of Composition B>
Preparation of liquid composition B (y-1) (for preparation of composition (C-1) used in Examples 1 and 9)
The container contains 966.0 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 0.9 parts of torhydroquinone, 3.4 parts of 4-methyl-2,6-ditercious butylphenol, and 29.7 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-1).

Preparation of liquid composition B (y-2) (for preparation of composition (C-2) used in Examples 2 and 10)
The container contains 930.0 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 1.9 parts of tolhydroquinone, 7.3 parts of 4-methyl-2,6-ditercious butylphenol, and 60.7 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-2).

Preparation of liquid composition B (y-3) (for preparation of composition (C-3) used in Examples 3 and 11)
The container contains 899.3 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 2.7 parts of torhydroquinone, 10.0 parts of 4-methyl-2,6-ditercious butylphenol, and 88.0 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-3).

Preparation of liquid composition B (y-4) (for preparation of composition (C-4) used in Examples 4 and 12)
The container contains 962.1 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 1.1 parts of tolhydroquinone, 4.0 parts of 4-methyl-2,6-ditercious butylphenol, and 32.8 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-4).

Preparation of liquid composition B (y-5) (for preparation of composition (C-5) used in Examples 5 and 13)
The container contains 969.0 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 0.8 parts of torhydroquinone, 3.1 parts of 4-methyl-2,6-ditercious butylphenol, and 27.1 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-5).

Preparation of liquid composition B (y-6) (for preparation of composition (C-6) used in Examples 6 and 14)
973.2 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company), 0.73.2 parts of tolhydroquinone, 2.8 parts of 4-methyl-2,6-ditercious butylphenol, and 23.3 parts of triphenylphosphine in a container. Was mixed and stirred until a uniform solution was obtained to obtain composition B (y-6).

Preparation of liquid composition B (y-7) (for preparation of composition (C-7) used in Examples 7 and 15)
The container contains 961.3 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 1.1 parts of tolhydroquinone, 3.9 parts of 4-methyl-2,6-ditercious butylphenol, and 33.7 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-7).

Preparation of liquid composition B (y-8) (for preparation of composition (C-8) used in Examples 8 and 16)
The container contains 871.0 parts of methacrylic acid (manufactured by Mitsubishi Gas Chemical Company, Inc.), 3.7 parts of tolhydroquinone, 13.9 parts of 4-methyl-2,6-ditercious butylphenol, and 111.4 parts of triphenylphosphine. The mixture was stirred until a uniform solution was obtained to obtain composition B (y-8).

The prepared liquid compositions A and B were mixed at the ratios shown in Table 1 and stirred until a uniform solution was obtained to obtain liquid compositions (C-1 to 8) for intermediate substrates. Further, the viscosity of the prepared liquid composition, the molar ratio of unsaturated group-containing monocarboxylic acid in the composition (B) to the number of molar epoxy groups in the composition (A) (B / A), and the epoxy formed after aging. The theoretical ethylenically unsaturated group equivalents of (meth) acrylates are shown in Table 1. Table 1 shows the preparation of liquid compositions. In Table 1, * 1 indicates the molar ratio (B / A) of unsaturated group-containing monocarboxylic acid in the composition (B) to the number of moles of epoxy groups in the composition (A).

[Comparative example resin preparation]
As a comparative example, a resin was prepared.
Preparation of Epoxy (Meta) Acrylate Resin (EA-1) (Compositions (C-9) Used in Comparative Examples 1 and 4)
800.0 parts of the above epoxy methacrylate (EA-1), 192.0 parts of Cosmonate LL (modified diphenylisocyanate manufactured by Mitsui Chemicals, Inc.), Perbutyl E (monooxycarbonate-based organic peroxide manufactured by NOF Corporation) 8. 0 parts were prepared at 25 ° C. and stirred until a uniform solution was obtained to obtain a composition (C-9).

Preparation of Epoxy (Meta) Acrylate Resin (EA-2) (Composition (C-10) Used in Comparative Examples 2 and 5)
Prepare 990.0 parts of the above epoxy (meth) acrylate (EA-2) and 10.0 parts of perbutyl E (monooxycarbonate-based organic peroxide manufactured by NOF Corporation) at 80 ° C., and stir until a uniform solution is obtained. The composition (C-10) was obtained.

[Comparison liquid Urethane acrylate forming liquid composition liquid preparation]
Further, as a comparative example, liquid compositions A and B for forming urethane acrylate were prepared, respectively. The prepared liquid compositions A and B were mixed at the ratios shown in Table 1 and stirred until a uniform solution was obtained to obtain a liquid composition (C-11) for an intermediate base material.

Preparation of urethane acrylate-forming liquid composition liquid A (z-1) (for preparation of composition (C-11) used in Comparative Examples 3 and 6)
A container is mixed with 975.6 parts of isophorone diisocyanate (manufactured by Evonik) and 24.4 parts of perbutyl E (monooxycarbonate-based organic peroxide manufactured by NOF Corporation), and stirred at room temperature until a uniform solution is obtained. A (z-1) was obtained.

Preparation of urethane acrylate-forming liquid composition liquid B (z-2) (for preparation of composition (C-11) used in Comparative Examples 3 and 6)
409.8 parts of the polyester polyol 1, 437.7 parts of 2-hydroxypropyl methacrylate (light ester HOP (N) manufactured by Kyoei Co., Ltd.), 151.0 parts of diethylene glycol dimethacrylate (NK ester 2G manufactured by Shin-Nakamura Chemical Co., Ltd.) in a container. , 0.1 part of toluhydroquinone, 0.5 part of 4-methyl-2,6-ditershary butylphenol, and 0.9 part of dibutyltin dilaurate are blended and stirred until a uniform solution is obtained, and the composition B (z- 2) was obtained.

The viscosities of the resins prepared above are listed in Table 1.
[Measurement of shrinkage rate of composition alone]
For the purpose of evaluating the dimensional stability, the shrinkage rate of the cured product of the above liquid composition (C-1 to 11) was measured. The shrinkage rate was calculated from the liquid specific density and the cured product specific gravity. Further, (C-1 to 8 and C-11) were cured after the thickening was completed.
Table 2 shows the measurement results of the aging conditions and the shrinkage rate.

Table 3 shows the intermediate base material (prepreg) preparation conditions, the prepreg impregnation state, and the thickening conditions.

[Creation of intermediate base material]
Preparation of prepreg (P-1 to 11) 33 cm square carbon fiber (3K twill, TR3523M manufactured by Mitsubishi Chemical Corporation) using the liquid composition (C-1 to 11) shown in Table 1 in the formulation shown in Table 3. A prepreg was obtained by impregnating 10 sheets one by one and then aging under each condition. The obtained prepreg had about 60% by weight of fibers.

The liquid compositions (C-1 to 9 and C-11) shown in Table 1 are mixed with 10 pieces of 33 cm square carbon fibers (3K twill, TR3523M manufactured by Mitsubishi Chemical Corporation) in the formulation shown in Table 3. Was impregnated with prepreg and then aged under each condition to obtain a prepreg. The obtained prepreg had about 60% by weight of fibers. C-10 (Comparative Example 2) was impregnated one by one by a hot melt method, and then 10 sheets were laminated to prepare a prepreg.

Preparation of C-SMC (S-1 to 11) The liquid compositions (C-1 to 9 and C-11) shown in Table 1 were cut into 25 mm lengths and 25 cm squares with the formulation shown in Table 4. A uniformly dispersed carbon fiber (TR50S 12L manufactured by Mitsubishi Chemical Corporation) was impregnated and then aged under each condition to obtain C-SMC. The obtained C-SMC had about 55% by weight of fibers. In S-10 (Comparative Example 5), a tow prepreg was prepared by a hot melt method, and then the prepared tow prepreg was cut to a length of 25 mm, randomly oriented, and pressed at 50 ° C. to obtain C-SMC. ..

[Evaluation of impregnation property of intermediate base material (prepreg, C-SMC)]
The degree of impregnation was visually confirmed. ◎: Very good 〇: Good ×: Unimpregnated part

[Odor evaluation of intermediate base material]
The odor when the film was peeled off was confirmed. 〇: No pungent odor ×: With pungent odor

[Molding of intermediate base material]
Molding of prepreg Using the prepared prepreg (P-1 to 11), it was molded by a press (using a 100-ton press machine manufactured by Toho Press Mfg. Co., Ltd.) to obtain a molded plate (Examples 1 to 8 and comparison). Examples 1 to 3). The press molding temperature was 130 ° C., the molding pressure was 1 MPa, and the molding time was 7 minutes.

Molding of C-SMC Using the prepared C-SMC (S-1 to 11), molding was performed by a press (using a 100-ton press machine manufactured by Toho Press Mfg. Co., Ltd.) to obtain a molded plate (Example 9). ~ 16 and Comparative Examples 4 to 6). The press molding temperature was 130 ° C., the molding pressure was 8 MPa, and the molding time was 7 minutes.

[Measurement of physical properties of molded plate]
The obtained molded plate was subjected to a bending test, an interlayer shear test, a moldability and an impregnation property test.

Bending test Measurements were made according to ASTM D 790.

Interlayer shear test The measurement was performed by a method according to ASTM D 2344. The results of the bending test, the interlayer shear test, and the physical property evaluation test are shown in Tables 5 and 6.

[Chemical resistance test]
As a chemical resistance test, the molded product was immersed in a hydrochloric acid solution having a concentration of 10% and a sodium hydroxide solution having a concentration of 10% for 2 months, respectively. A bending test was performed after immersion, and the bending strength retention rate was measured. The test results are shown in Table 7.

As a result, it can be seen from Tables 3 and 4 that the liquid composition has an excellent impregnation property into the base material because it has a lower viscosity than the hot melt resin. Further, as shown in Table 2, as compared with the method of mixing the radically polymerizable resin and the thickener, the intermediate base material after aging has no odor, shrinkage during curing is small, and the intermediate base material is excellent in dimensional stability. You can see that it gives. Further, from Tables 5 to 7, it can be seen that the intermediate base material provides a composite material having excellent mechanical properties and excellent chemical resistance.

Table 4 shows the intermediate base material (C-SMC) preparation conditions and the impregnation state of C-SMC. In Table 4, * 2 indicates that the toe prepreg (hot melt method) is prepared in advance, and then the prepreg is cut to 25 mm to form C-SMC.

Table 5 shows the results of the bending test, the interlayer shear test, the physical property evaluation test result, the moldability and the impregnation property test of the prepreg molded plate.

Table 6 shows the results of the bending test, the interlayer shear test, the physical property evaluation test result, the moldability and the impregnation property test of the C-SMC molded plate.

Table 7 shows the test results when the bending test was performed after immersion and the bending strength retention rate was measured.

From the above results, according to the present invention using the liquid composition having excellent impregnation property, a fiber reinforced plastic intermediate having better impregnation property as compared with a resin for hot melt without using styrene which is harmful to the human body and odorous. A base material can be obtained, and a molded product using the intermediate base material can provide FRP having high strength and excellent FRP dimensional stability and chemical resistance.

Since the liquid composition for intermediate base material and the intermediate base material of the present invention are lightweight and have high strength, the application range is not limited to these, such as transportation equipment, industrial materials, civil engineering reinforcing materials, and sports equipment. Can be used over.

Claims (9)

A liquid composition for a matrix in a fiber-reinforced plastic intermediate base material obtained by blending the following (A) and (B), for forming an epoxy acrylate through a process of aging in a state of being impregnated in a fiber or a woven fabric. Liquid composition.
A composition (A) containing a compound (a1) having two or more epoxy groups, a composition (B) containing the following (b1) and the following (b2) as essential components.
(B1) Unsaturated group-containing monocarboxylic acid (b2) Polymerization inhibitor The liquid composition according to claim 1, wherein the polymerization initiator (C) and / or the esterification catalyst (D) is blended with the compositions (A) and / or (B). Further, according to claim 1 or 2, the epoxy reactive group molar ratio (B / A) in the composition (B) to the number of moles of epoxy groups in the composition (A) is 0.8 to 1.2. The liquid composition described. The liquid composition according to any one of claims 1 to 3, wherein the composition (A) and / or (B) contains a polymerizable monomer (E) containing no epoxy-reactive group. thing. The liquid composition according to any one of claims 1 to 4, wherein the content of the polymerizable monomer (E) is 0 to 40% by weight with respect to the total weight of the compositions (A) and (B). thing. A fiber-reinforced plastic intermediate base material obtained by impregnating a fiber material with the liquid composition according to any one of claims 1 to 5. A step of impregnating a fiber material with the liquid composition according to any one of claims 1 to 5 with an arbitrary composition, and a step of aging the fiber-reinforced plastic intermediate base material obtained by the impregnation are included. A method for producing a fiber reinforced plastic intermediate base material. The method according to claim 7, wherein the aging temperature is 30 to 90 ° C. A fiber-reinforced composite material obtained by curing the reinforced plastic intermediate base material according to claim 6.