JP2017214482A - Curable resin, curable resin composition, sizing agent for fiber, fiber for reinforcement, resin composition for fiber-reinforced composite material, and fiber-reinforced composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sizing agent for fiber capable of obtaining a fiber for reinforcement excellent in adhesion with a matrix resin, and a curable resin and a curable resin composition usable in the same, and to provide a fiber-reinforced composite material excellent in adhesion between the fiber for reinforcement and the matrix resin and a resin composition for forming fiber-reinforced composite material capable of forming the same.SOLUTION: A curable resin is obtained by reaction of an isocyanate group-terminated prepolymer obtained by reaction of (A) polyisocyanate, (B) a specific divinyl compound and (C) polysiloxane having at least two hydroxy groups, with at least one compound selected from the group consisting of (D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) specific hydroxyalkyl(meth)acrylate.SELECTED DRAWING: None

Description

  The present invention relates to a curable resin, a curable resin composition containing the curable resin, a fiber sizing agent, a reinforcing fiber obtained by using the sizing agent, a reinforcing fiber, and a fiber reinforced composite material including a thermosetting resin. The present invention relates to a forming resin composition and a fiber-reinforced composite material.

  Fiber reinforced composite materials composed of reinforcing fibers made of chemical fibers such as carbon fibers and matrix resins are lightweight yet high strength, and are used in various fields such as airplanes, automobiles, and sporting goods. . As the matrix resin, a thermosetting resin is mainly used, and an epoxy resin is mainly used. However, as a thermosetting resin, for example, an unsaturated polyester resin or a vinyl ester is used because the molding cycle is short and the molding cost can be reduced. Radical polymerizable resins such as resins and acrylic resins are also frequently used.

  By the way, the reinforcing fiber is treated with a sizing agent in order to suppress the occurrence of fuzz and yarn breakage during processing. In order for the reinforcing fiber to effectively reinforce the matrix resin, it is important that the reinforcing fiber and the matrix resin are sufficiently bonded. Therefore, as a sizing agent, adhesion to an epoxy resin is usually used. An epoxy resin is used in consideration. However, when the above-mentioned radical polymerizable resin is used as the matrix resin, the adhesion between the reinforcing fiber and the matrix resin may be insufficient.

  Techniques for improving the adhesion between reinforcing fibers and radical polymerizable resins have been studied so far. For example, Patent Documents 1 and 2 listed below disclose sizing agents using a urethane compound having a polymerizable unsaturated double bond.

International Publication WO2011 / 092962 Pamphlet JP 2001-003266 A

  However, even when the above sizing agent is used, there are cases where sufficient adhesiveness is not yet obtained.

  The present invention relates to a fiber sizing agent capable of obtaining a reinforcing fiber excellent in adhesiveness to a matrix resin, a curable resin and a curable resin composition that can be used therein, and a reinforcing fiber and a matrix resin. An object of the present invention is to provide a fiber-reinforced composite material having excellent adhesiveness and a resin composition for forming a fiber-reinforced composite material capable of forming the same.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by using a curable resin having a specific structure, and have completed the present invention.

  That is, according to one aspect of the present invention, (A) a polyisocyanate, (B) a compound represented by the following general formula (1-1), and (C) a polysiloxane having at least two hydroxy groups are reacted. (D1) a compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) the following general formula (2) And a curable resin obtained by reacting at least one compound selected from the group consisting of hydroxyalkyl (meth) acrylates.

［式（１−１）中、Ｒ^１１及びＲ^１２はそれぞれ独立に水素原子又はメチル基を表し、Ｒ^２１及びＲ^２２はそれぞれ独立に単結合又はエーテル結合を含んでいてもよい炭素数１〜１２のアルキレン基を表し、Ｘは下記一般式（１−２）で表される２価の基を表し、

｛式（１−２）中、Ａ^１１及びＡ^１２はそれぞれ独立に炭素数２〜４のアルキレン基を表し、Ｒ^３１及びＲ^３２はそれぞれ独立に炭素数１〜３のアルキル基、フェニル基又はハロゲノ基を表し、Ｒ^４は単結合、−ＣＲ^５ _２−（ただし、Ｒ^５は水素原子、炭素数１〜３のアルキル基又はフェニル基を表す）で表される基又は−ＳＯ_２−を表し、ｂ１及びｂ２はそれぞれ独立に０〜２の整数を表し、ｃ１及びｃ２はそれぞれ独立に０〜１０の整数を表す。｝
ａは１〜１０の整数を表す。］

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

［式（２）中、Ｒ^５は水素原子又はメチル基を表し、Ｒ^６は炭素数２〜１０のアルキレン基を表す。］

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ]

  One aspect of the present invention is obtained by reacting (A) a polyisocyanate, (B) a compound represented by the above general formula (1-1), and (C) a polysiloxane having at least two hydroxy groups. An isocyanate group-terminated prepolymer, (D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) in the general formula (2) The present invention relates to a method for producing a curable resin comprising a step of reacting at least one compound selected from the group consisting of represented hydroxyalkyl (meth) acrylates.

  Although the reason why the above-mentioned problem is achieved by the curable resin according to the present invention is not necessarily clear, the present inventors infer as follows. According to the curable resin according to the present invention, a cured resin having excellent self-repairability can be formed. Specifically, for example, when a film-like resin cured product obtained by curing the composition containing the curable resin according to the present invention is physically damaged, scratches cannot be visually confirmed in a short time. It will be repaired. When a fiber reinforced composite material is formed from a reinforcing fiber in which a curable resin having such characteristics is adhered to a fiber and a matrix resin, a cured resin product having excellent self-healing properties is formed on the surface of the reinforcing fiber. Even if there is a gap such as a slight gap or misalignment between the reinforcing fiber and the matrix resin due to shrinkage when the matrix resin hardens or impact on the fiber reinforced composite, etc. It is considered that the cured resin on the fiber can restore the original shape again. It is considered that the adhesion at the fiber-reinforced composite material interface is sufficiently improved by sufficiently maintaining the state in which the reinforcing fibers and the matrix resin are in close contact with each other by such an action. In addition, since the curable resin of the invention has a radical polymerizable double bond, when a radical polymerizable resin is used as the matrix resin, a cured resin that is more strongly bonded to the matrix resin is formed by interaction. This is presumed to be one of the reasons that the adhesion at the fiber-reinforced composite material interface is sufficiently improved.

  One aspect of the present invention relates to a curable resin composition containing the curable resin according to the present invention, and a cured resin that is a cured product thereof.

  One aspect of the present invention relates to a fiber sizing agent containing the curable resin according to the present invention.

  By treating the fibers with the fiber sizing agent according to the present invention, reinforcing fibers having excellent adhesion to the matrix resin can be obtained.

  One aspect of the present invention relates to a reinforcing fiber comprising a fiber and the curable resin according to the present invention attached to the fiber.

  One aspect of the present invention relates to a fiber-reinforced composite material-forming resin composition comprising the reinforcing fiber according to the present invention and a thermosetting resin.

  By molding the resin composition for forming a fiber-reinforced composite material according to the present invention into a predetermined shape and curing it, a fiber-reinforced composite material having excellent adhesion between the reinforcing fiber and the matrix resin can be obtained.

  One aspect of the present invention relates to a fiber reinforced composite material containing a cured product of the resin composition for forming a reinforced fiber composite material according to the present invention.

  One aspect of the present invention relates to a method for producing a fiber reinforced composite material comprising a step of curing the resin composition for forming a reinforced fiber composite material according to the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the fiber sizing agent which can obtain the fiber for reinforcement excellent in adhesiveness with a matrix resin, the curable resin and curable resin composition which can be used for it, and the fiber for reinforcement and a matrix It is possible to provide a fiber reinforced composite material excellent in adhesiveness with a resin and a resin composition for forming a fiber reinforced composite material capable of forming the same.

  According to the curable resin composition containing the curable resin of the present invention, it is possible to form a cured resin having excellent self-restoring properties.

  According to the fiber sizing agent of the present invention, a reinforcing fiber excellent in adhesiveness with a thermosetting resin, particularly a radical polymerizable resin, can be obtained.

  One embodiment of the method for producing a curable resin according to the present invention includes (A) a polyisocyanate (hereinafter sometimes referred to as (A) component) and (B) a compound represented by the following general formula (1-1). (Hereinafter also referred to as component (B)) and (C) a polysiloxane having at least two hydroxy groups (hereinafter also referred to as component (C)), and an isocyanate group-terminated prepolymer obtained by reacting them. A polymer, (D1) a diol compound having 2 to 13 carbon atoms (hereinafter sometimes referred to as (D1) component), (D2) a compound having an anionic hydrophilic group and at least two active hydrogens (hereinafter referred to as (D2 And (D3) a small amount selected from the group consisting of hydroxyalkyl (meth) acrylates represented by the following general formula (2) (hereinafter also referred to as (D3) component). Kutomo one compound (hereinafter, (D) sometimes referred to as the component) comprises the step of reacting, with.

［式（１−１）中、Ｒ^１１及びＲ^１２はそれぞれ独立に水素原子又はメチル基を表し、Ｒ^２１及びＲ^２２はそれぞれ独立に単結合又はエーテル結合を含んでいてもよい炭素数１〜１２のアルキレン基を表し、Ｘは下記一般式（１−２）で表される２価の基を表し、

｛式（１−２）中、Ａ^１１及びＡ^１２はそれぞれ独立に炭素数２〜４のアルキレン基を表し、Ｒ^３１及びＲ^３２はそれぞれ独立に炭素数１〜３のアルキル基、フェニル基又はハロゲノ基を表し、Ｒ^４は単結合、−ＣＲ^５ _２−（ただし、Ｒ^５は水素原子、炭素数１〜３のアルキル基又はフェニル基を表す）で表される基又は−ＳＯ_２−を表し、ｂ１及びｂ２はそれぞれ独立に０〜２の整数を表し、ｃ１及びｃ２はそれぞれ独立に０〜１０の整数を表す。｝
ａは１〜１０の整数を表す。］

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

In the present specification, in the formulas (1-1) and (1-2), when a is 2 or more, a plurality of A ¹¹ , A ¹² , R ³¹ , R ³² and R ⁴ are the same. When b1 is 2, a plurality of R ³¹ may be the same or different, and when b2 is 2, a plurality of R ³² may be the same. May be different.

［式（２）中、Ｒ^５は水素原子又はメチル基を表し、Ｒ^６は炭素数２〜１０のアルキレン基を表す。］

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ]

  As the component (A), a compound having two or more isocyanate groups can be used, and examples thereof include modified polyisocyanates such as diisocyanate, triisocyanate, tetraisocyanate, diisocyanate dimer or trimer.

  Examples of the diisocyanate include aliphatic diisocyanate, alicyclic diisocyanate, and aromatic diisocyanate. Examples of these diisocyanates include aliphatic diisocyanate compounds such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; isophorone diisocyanate, hydrogenated xylylene diisocyanate, dicyclohexylmethane diisocyanate, norbornane diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane. And alicyclic diisocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate (MDI), naphthalene diisocyanate, tolidine diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, and the like.

  Examples of the triisocyanate and tetraisocyanate include triphenylmethane triisocyanate, dimethyltriphenylmethane tetraisocyanate, and tris (isocyanatophenyl) -thiophosphate.

  The modified polyisocyanate derived from diisocyanate is not particularly limited as long as it has two or more isocyanate groups. For example, biuret structure, isocyanurate structure, urethane structure, uretdione structure, allophanate structure, trimer structure And the like, adducts of aliphatic isocyanates of trimethylolpropane, polymeric MDI, and the like.

  The component (A) is preferably a diisocyanate, more preferably an aliphatic diisocyanate and an alicyclic diisocyanate, and more preferably hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane, from the viewpoint that the self-healing property and adhesiveness of the resulting curable resin are more excellent. More preferred are diisocyanate, norbornane diisocyanate and 1,3-bis (isocyanatomethyl) cyclohexane.

  Polyisocyanate may be used individually by 1 type, or may be used in combination of 2 or more type.

The component (B) is a compound represented by the above general formula (1-1), but R ¹¹ and R ¹² in the general formula (1-1) are self-repairing and adhesion of the resulting curable resin. From the viewpoint of better properties, a hydrogen atom is preferable.

R ²¹ and R ²² in the general formula (1-1) are preferably single bonds from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

When R ²¹ or R ²² is an alkylene group having 1 to 12 carbon atoms that may contain an ether bond, for example, a methylene group, an ethylene group, a trimethylene group, a propylene group, an n-butylene group, an n-pentylene group, n- hexylene group, n- heptylene group, n- octylene _{group, - (CH 2) 2 -O} -CH 2 - , and the like.

A ¹¹ and A ¹² in the general formula (1-2) are preferably an ethylene group and a propylene group, and more preferably an ethylene group, from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

  C1 and c2 in the general formula (1-2) are preferably 0 to 4 and more preferably 0 to 2 from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

R ³¹ and R ³² in the general formula (1-2) are preferably an alkyl group having 1 to 3 carbon atoms from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

  As for b1 and b2 in General formula (1-2), 0 is preferable from the viewpoint that the self-repairing property and adhesiveness of the curable resin obtained are more excellent.

R ⁴ in the general formula (1-2) is preferably a group represented by —CR ⁵ ₂ — from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness, and R ⁵ is hydrogen. An atom or a methyl group is preferable, and a methyl group is more preferable.

  In the general formula (1-1), 1 to 6 is preferable and 1 to 3 is more preferable from the viewpoint that the self-healing property and adhesiveness of the resulting curable resin are more excellent.

［式（３）中、Ｘ及びａは、上記一般式（１−１）におけるＸ及びａと同義である。］ The compound represented by the general formula (1) can be obtained, for example, by reacting a compound represented by the following general formula (3) with a terminal unsaturated carboxylic acid.

[In Formula (3), X and a are synonymous with X and a in the said General formula (1-1). ]

  The compound represented by the general formula (3) can be obtained, for example, by a reaction between a bisphenol compound or a biphenyl compound and epichlorohydrin. Examples of the bisphenol compound include bisphenol A, bisphenol F, bisphenol AD, bisphenol S, those having a halogeno group substituted on their benzene rings, and their alkylene oxide adducts. Examples of the biphenyl compound include 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl and the like.

［式（４）中、Ｒ^７は上記一般式（１−１）におけるＲ^１１及びＲ^１２と同義であり、Ｒ^８は上記一般式（１−２）におけるＲ^２１及びＲ^２２と同義である。］ Examples of the terminal unsaturated carboxylic acid include compounds represented by the following general formula (4).

[In Formula (4), R ⁷ has the same meaning as R ¹¹ and R ¹² in General Formula 1-1, and R ⁸ has the same meaning as R ²¹ and R ²² in General Formula 1-2. . ]

  Examples of the compound represented by the formula (4) include acrylic acid, methacrylic acid, 3-butenoic acid, 4-pentenoic acid, 5-hexenoic acid, 6-heptenoic acid, 7-octenoic acid, 8-nonenoic acid, Examples include 9-decenoic acid, 10-undecenoic acid, and 3-allyloxypropionic acid. Among these, acrylic acid and methacrylic acid are preferable from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

［式（５）中、Ａ^２１及びＡ^２２はそれぞれ独立に炭素数２〜４のアルキレン基を表し、ｄ１及びｄ２はそれぞれ独立に０〜２５の整数を表し、Ｒ^８１及びＲ^８２はそれぞれ独立に単結合又は炭素数１〜６のアルキレン基を表し、ｅは１０〜５００の整数を表す。］ (C) As a component, the compound represented by following General formula (5) is mentioned, for example.

[In Formula (5), A ²¹ and A ²² each independently represent an alkylene group having 2 to 4 carbon atoms, d 1 and d 2 each independently represent an integer of 0 to 25, and R ⁸¹ and R ⁸² are each independently Represents a single bond or an alkylene group having 1 to 6 carbon atoms, and e represents an integer of 10 to 500. ]

Examples of A ²¹ and A ²² include an ethylene group and a propylene group, and an ethylene group is preferred from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

In terms of d1 and d2 in the formula (5), 0 (that is,-(A ²¹ O)-and-(OA ²² )-is a single bond from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness. ) To 15 are preferable, and 0 to 10 are more preferable.

R ⁸¹ and R ^{82 in} Formula (5) are preferably a single bond or an alkylene group having 1 to 3 carbon atoms from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness. More preferred is an alkylene group of 3.

When R ⁸¹ and R ⁸² are alkylene groups having 1 to 6 carbon atoms, examples include methylene group, ethylene group, propylene group, trimethylene group, n-butylene group, n-pentylene group, and n-hexylene group. .

  E in Formula (5) is preferably 15 to 100, more preferably 15 to 50, from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

  The component (D) is represented by (D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) the general formula (2). And at least one compound selected from the group consisting of hydroxyalkyl (meth) acrylates.

  Examples of the component (D1) include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-heptanediol, neopentyl glycol, 1,6-hexanediol, and 3-methyl. -Alkanediols such as 1,5-pentanediol, diols having ether groups such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedi And cycloalkanediols such as methanol. From the viewpoint that the self-healing property and adhesiveness of the resulting curable resin are more excellent, alkanediol and diol having an ether group are preferable, and alkanediol having 2 to 6 carbon atoms is more preferable.

Examples of the anionic hydrophilic group in the component (D2) include a carboxy group (—COOH), a carboxylate group (—COO ⁻ ), a sulfo group (—SO ₃ H), and a sulfonate group (—SO ₃ ⁻ ). From the viewpoint that the resulting curable resin is more excellent in emulsifiability in hydrophilic solvents such as alcohol, ketone and acetate, water and the like, a carboxy group and a carboxylate group are preferable.

  Examples of the component (D2) include C2-C8 carboxyl groups such as 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2'-dimethylolpentanoic acid, and salts thereof. And / or a carboxylate group-containing compound, 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, dicarboxylic acids such as 5- [4-sulfophenoxy] isophthalic acid and salts thereof, ethylene glycol, propylene glycol, Examples thereof include a sulfo group and / or a sulfonate group-containing polyester polyol obtained by reacting with a low molecular weight polyol such as 1,4-butanediol, 1,6-hexanediol, or neopentyl glycol. These can be used individually by 1 type or in combination of 2 or more types. Moreover, the polyester polyol which has a pendant type carboxyl group obtained by making diol which has a carboxyl group, aromatic dicarboxylic acid, fatty acid dicarboxylic acid, etc. react, or its salt is also mentioned as (D2) component. Further, it may be obtained by further mixing and reacting a diol having no carboxyl group during the above reaction. 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid are preferred from the viewpoint that the resulting curable resin is more excellent in emulsifiability in the hydrophilic solvent and water.

As the component (D3), R ⁵ in the general formula (2) is preferably a hydrogen atom from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness.

R ⁶ in the general formula (2) may be a linear or branched alkylene group having 2 to 10 carbon atoms, such as a methylene group, an ethylene group, a propylene group, a trimethylene group, n -Butylene group, n-pentylene group, n-hexylene group, n-heptylene group, n-octylene group, etc. are mentioned. R ⁶ is preferably an alkylene group having 2 to 6 carbon atoms from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness. Examples of such hydroxyalkyl (meth) acrylates include hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, and 6-hydroxyhexyl acrylate.

  The component (D) preferably contains at least (D1) a diol compound having 2 to 13 carbon atoms from the viewpoint that the resulting curable resin is more excellent in self-repairability and adhesiveness. Moreover, from the viewpoint that the emulsifiability of the obtained curable resin in the hydrophilic solvent or water is more excellent, it is preferable to include a compound having at least (D2) an anionic hydrophilic group and at least two active hydrogens. .

  In the method of this embodiment, the (A) component, the (B) component, and the (C) component are reacted to obtain an isocyanate group-terminated prepolymer, and then the above-mentioned (D) component is reacted with the isocyanate group-terminated prepolymer. be able to.

  When the isocyanate group-terminated prepolymer is produced, the component (A), the component (B) and the component (C) are combined with the component (A) with respect to the number of hydroxy groups derived from the component (B) and the component (C). It is preferable to make it react by the compounding quantity that the number of the isocyanate group derived from becomes excess.

  From the viewpoint that the self-healing property and adhesiveness of the resulting curable resin are more excellent, the component (A), the component (B) and the component (C) are composed of an isocyanate group derived from the component (A), the component (B), and (C) It is preferable to make it react so that the molar ratio with the hydroxy group derived from a component may become isocyanate group: hydroxy group = 100: 50-100: 95, and it reacts so that it may become 100: 55-100: 90. More preferably.

  The blending ratio of the component (B) and the component (C) is (B) component: (C) component = 1: 9 in terms of molar ratio from the viewpoint of better self-repairability and adhesiveness of the resulting curable resin. 9: 1 is preferable, 3: 7 to 8: 2 is more preferable, and 5: 5 to 7: 3 is more preferable.

  As reaction temperature, 40-150 degreeC is suitable, and you may add a catalyst as needed. Examples of the catalyst include carboxylic acid metal salts (potassium, tin, bismuth, etc.), and specific examples include dibutyltin dilaurate, stannous octoate, dibutyltin-2-ethylhexanoate, and the like. As a compounding quantity of a catalyst, 0.001-0.1 mass% is suitable with respect to the total mass of a reaction material (for example, (A) component, (B) component, and (C) component), 0.005 -0.03 mass% is more suitable. Moreover, the organic solvent and diluent which do not react with an isocyanate group can be added during reaction or after completion | finish of reaction.

  As the organic solvent, for example, acetone, methyl ethyl ketone, toluene, tetrahydrofuran, dioxane, dimethylformamide, N-methylpyrrolidone and the like can be used.

  Examples of the diluent include ethylenically unsaturated monomers such as esters of C1-C12 alcohols or polyhydric alcohols with (meth) acrylic acid, styrene, α-methylstyrene, (meth) acrylic acid amide. Is mentioned. Of these, styrene is preferred.

  Next, (D) component can be made to react with the isocyanate group terminal prepolymer obtained by said reaction. As the component (D), the components (D1) to (D3) may be used alone or in combination of two or three. In each of the components (D1) to (D3), a plurality of compounds can be used in combination. From the viewpoint that the self-healing property of the resulting curable resin is more excellent, it is preferable to use the component (D1). Moreover, it is preferable to use (D2) component from a viewpoint that the emulsifiability to the said hydrophilic solvent, water, etc. of the curable resin obtained is more excellent.

  About the compounding quantity of the (D1) component-(D3) component in (D) component, it is (D1) with respect to the total number of moles of (D) component from a viewpoint that the self-healing property of the curable resin obtained is more excellent. The component is preferably 50 to 100 mol%, more preferably 80 to 100 mol%, the component (D2) is preferably 0 to 50 mol%, more preferably 0 to 20 mol%, and the component (D3) is 0 to 50 mol%. % Is preferable, and 0 to 20 mol% is more preferable. Moreover, when mix | blending (D2) component, an anionic hydrophilic group is 0.00 with respect to the obtained curable resin from a viewpoint that the emulsifiability to the said hydrophilic solvent, water, etc. of the obtained curable resin is more excellent. It is preferable to adjust so that it may be contained in the amount of 05-5.0 mass%, and it is more preferable to adjust so that it may be included in the amount of 0.1-3.0 mass%.

  Moreover, you may make a low molecular weight compound react with an isocyanate group terminal prepolymer in the range which does not impair the effect of this invention. The low molecular weight compound preferably has a molecular weight of 400 or less, more preferably 300 or less. Examples of such low molecular weight compounds include low molecular weight polyhydric alcohols such as trimethylolpropane, pentaerythritol, sorbitol, ethylenediamine, propylenediamine, hexamethylenediamine, diaminocyclohexylmethane, piperazine, 2-methylpiperazine, isophoronediamine, And low molecular weight polyamines such as diethylenetriamine and triethylenetetramine.

  As a compounding quantity of (D) component and a low molecular weight compound in said case, the quantity in which the isocyanate group of an isocyanate group terminal prepolymer does not remain is preferable. For example, the amount of isocyanate group in the isocyanate group-terminated prepolymer is measured by a technique such as titration, and the amount of the isocyanate group in the component (D) and the low molecular weight compound that can react with the isocyanate group is measured. The blending amounts of the component (D) and the low molecular weight compound can be set so as to be equivalent to each other.

  The reaction between the isocyanate group-terminated prepolymer, the component (D) and, if necessary, the low molecular weight compound can be carried out, for example, at a temperature of 20 to 100 ° C., and is preferably continued until no isocyanate group remains. The residual isocyanate group can be confirmed by titration or peak observation derived from the isocyanate group in IR.

  As a weight average molecular weight of curable resin obtained, 3000-150,000 are mentioned, for example, and 5000-80000 are preferable from a viewpoint that a handleability is more excellent. The weight average molecular weight of curable resin can be adjusted by adjusting the molar ratio of the usage-amount of (A) component, (B) component, (C) component, and (D) component, for example. In addition, the average molecular weight of curable resin can be calculated | required by the polyethylene glycol conversion method or the polystyrene conversion method, for example using gel permeation chromatography (GPC).

  Next, the curable resin composition according to the present invention will be described.

  The curable resin composition contains a curable resin obtained by the above-described reaction (hereinafter sometimes referred to as the curable resin of the present embodiment). The content of the curable resin of the present embodiment in the curable resin composition can be appropriately adjusted depending on the application. For example, the content is preferably 40% by mass or more and 85% by mass or more based on the total amount of the curable resin composition. More preferred.

  In the curable resin composition of the present embodiment, the curable resin obtained by the above-described reaction may be used as it is as the curable resin composition, or other components may be blended to form the curable resin composition. Other components may vary depending on the use of the curable resin composition, but include, for example, a polymerization initiator, a photosensitizer, a curing accelerator, an organic solvent for adjusting the viscosity, and a reactive diluent. It is done. In addition, components that accelerate the polymerization reaction of a curable resin such as a polymerization initiator, a photosensitizer, and a curing accelerator can prevent the occurrence of pot life due to a decrease in storage stability of the curable resin composition. From this point of view, it is preferably blended immediately before the curable resin composition is cured.

  A polymerization initiator is contained in order to accelerate the polymerization reaction of the curable resin. Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator that generates radicals by light. From the viewpoint of faster curing, it is preferable to use a photopolymerization initiator.

  Examples of the photopolymerization initiator include 2,2-diethoxyacetophenone, benzophenone, p-methoxybenzophenone, benzoylmethyl ether, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, acetophenone, propionphenone, xanthone, benzoylgi. Acid methyl, benzyl, naphthoquinone, 4-methylacetophenone, anthraquinone, t-butyl perbenzoate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2- Morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1 -Hydroxycyclo Cyclohexyl phenyl ketone, 3,6-bis (2-morpholino isobutyl) -9-butyl-carbazole, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl phosphine oxide, thioxanthone derivatives, and the like. Among these, from the viewpoint of curing speed, benzophenone, methyl benzoylformate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone and 2-hydroxy-2-methyl-1-phenylpropan-1-one Is preferred. These photoinitiators may be used individually by 1 type, and may use 2 or more types together. In the present embodiment, a photosensitizer can be used in combination. Examples of the photosensitizer include mono-, di- or triethanolamine, N-methyldiethanolamine, alkyl 4-dimethylaminobenzoate (alkyl group having 1 to 3 carbon atoms), 4-dimethylaminoacetophenone, and the like.

  Examples of the thermal polymerization initiator include known organic peroxides and azo compounds. Examples of the organic peroxide include ketone peroxide, peroxyketal, hydroperoxide (cumene hydroperoxide, etc.), diallyl peroxide, diacyl peroxide (benzoyl peroxide, lauroyl peroxide, etc.), peroxyester ( t-butylperoxy-2-ethylhexanoate), peroxydicarbonate, potassium persulfate, hydrogen peroxide, and the like. Examples of the azo compound include 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2′-azobis (2-methyl) propionate, 2,2'-azobis (isobutyric acid) dimethyl, 4,4'-azobis (4-cyanopentanoic acid), 2,2'-azobis (2-amidinopropane) dihydrochloride, and 2,2'-azobis {2 -Methyl-N- [2- (1-hydroxybutyl)]-propionamide}, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] and the like. Among these, 2,2'-azobis (isobutyronitrile) and dimethyl 2,2'-azobis (2-methyl) propionate are preferable from the viewpoint of curing speed. These thermal polymerization initiators may be used alone or in combination of two or more.

  As content of the polymerization initiator in curable resin composition, 10 mass parts or less are preferable with respect to 100 mass parts of curable resin of this embodiment, and 5 mass parts or less are more preferable.

  Examples of the curing accelerator include cobalt naphthenate, dimethylaniline, and acetylacetone.

  Examples of the organic solvent include methyl ethyl ketone, methyl isobutyl ketone, toluene, butyl acetate, methoxypropanol, methoxypropyl acetate, methobuta (3-methoxybutanol), 3-methoxybutyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether. , Diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate and the like.

  Examples of reactive diluents include styrene monomers, dienes, acrylic monomers, vinyl compounds, unsaturated dicarboxylic acid diesters, and imide compounds.

  Examples of styrene monomers include styrene derivatives substituted with styrene, alkyl, nitro, cyano, halogen, and the like, divinylbenzene, and the like.

  Examples of dienes include butadiene, 2,3-dimethylbutadiene, isoprene, chloroprene and the like.

  Examples of acrylic monomers include acrylic acid having a branched or straight chain alkyl group having 1 to 18 carbon atoms, acrylic acid having a bicyclic hydrocarbon group having 5 to 10 carbon atoms, and aromatic carbonization having 6 to 14 carbon atoms. Acrylic acid having a hydrogen group, an alkylene oxide adduct of acrylic acid having an aromatic hydrocarbon group having 6 to 14 carbon atoms, an acrylate ester of benzyl alcohol (or its alkylene oxide (1 to 5 mol) adduct), acrylic Allyl acid, propargyl acrylate, piperonyl acrylate, salicyl acrylate, furyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, pyranyl acrylate, phenethyl acrylate, cresyl acrylate, triphenylmethyl acrylate, cumyl acrylate Acrylic acid 3- (N, N-dimethylamino) ) Addition of propyl, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 1,6-hexanediol diacrylate, tricyclodecanediol diacrylate, trimethylolpropane (or its alkylene oxide (1-15 mol)) Product) triacrylic ester, pentaerythritol (or its alkylene oxide (1-15 mol) adduct), triacrylic ester, pentaerythritol (or its alkylene oxide (1-20 mol) adduct) tetraacrylic acid Esters, tetraacrylic acid ester of ditrimethylolpropane (or its adduct of alkylene oxide (1 to 20 mol)), hexaacrylic acid ester of dipentaerythritol (or its adduct of alkylene oxide (1 to 30 mol)) Acrylate, acrylic acid esters such as 1,1,1-trifluoroethyl acrylate, perfluoroethyl acrylate, perfluoro-n-propyl acrylate, perfluoro-i-propyl acrylate; Acrylic acid such as acrylic acid N, N-dimethylamide, acrylic acid N, N-diethylamide, acrylic acid N, N-dipropylamide, acrylic acid N, N-di-i-propylamide, acrylic acid anthracenylamide Amides; acrylic acid anilide, acryloylnitrile, acrolein and the like.

  Examples of the vinyl compound include vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N-vinyl pyrrolidone, vinyl pyridine, vinyl acetate and the like.

  Examples of the unsaturated dicarboxylic acid diester include diethyl citraconic acid, diethyl maleate, diethyl fumarate, diethyl itaconate and the like.

  Examples of the imide compound include monomaleimide compounds such as N-phenylmaleimide, N-cyclohexylmaleimide, N-laurylmaleimide, N- (4-hydroxyphenyl) maleimide, and N-acryloylphthalimide.

  Among these, from the viewpoints of compatibility with the curable resin of the present embodiment, vapor pressure, skin irritation, and low viscosity of the resin composition, acrylic acid of benzyl alcohol (or its adduct of alkylene oxide (1 to 5 mol)). Acid ester, 1,6-hexanediol diacrylate, tricyclodecanediol diacrylate, trimethylolpropane (or its adduct of alkylene oxide (1 to 15 mol)), pentaerythritol (or its alkylene oxide ( 1-15 mol) adduct) triacrylate ester, pentaerythritol (or its alkylene oxide (1-20 mol) adduct) tetraacrylate ester, ditrimethylolpropane (or its alkylene oxide (1-20 mol)) Additive) Tetraacrylic acid Este , Hexa acrylate esters of dipentaerythritol (or alkylene oxide (1 to 30 mol) adduct), styrene is preferred.

  A reactive diluent may be used individually by 1 type, and 2 or more types can also be mixed and used for it.

  The curable resin composition of the present embodiment may contain additives other than the components described above within a range that does not impair the effects of the present invention, depending on the application. Examples of such additives include leveling agents, plasticizers, antifoaming agents, ultraviolet absorbers, antioxidants, viscosity control agents, and the like.

  The curable resin composition of the present embodiment can be used, for example, as a fiber sizing agent or an adhesive described later.

  Next, the cured resin according to the present invention will be described. The cured resin according to the present invention is obtained by curing the curable resin composition of the present embodiment. For example, a cured resin can be obtained by curing a curable resin in the curable resin composition by a radical polymerization reaction.

  The method for curing the curable resin composition is not particularly limited, and the composition may be allowed to cure at room temperature and normal pressure. The composition may be heated, pressurized, or irradiated with active energy rays. It may be applied and cured. From the viewpoint that the curing time is shorter, it is preferable to perform heating, pressurization, active energy ray irradiation, or the like.

  Examples of active energy rays include visible light, infrared rays, ultraviolet rays, X-rays, α rays, β rays, γ rays, and electron beams. Of these, ultraviolet rays and electron beams are preferable from the viewpoints of safety and reaction efficiency.

The irradiation condition of the active energy ray can be appropriately selected depending on the type of the active energy ray. For example, as a preferable irradiation condition of ultraviolet rays, the illuminance is 1 to 1000 mW / cm ² , and the irradiation amount is 0.1 to 10,000 mJ / cm. ² is mentioned.

  As an active energy ray irradiation device, for example, a lamp light source such as a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, or an excimer lamp, a pulse such as an argon ion laser or a helium neon laser, a continuous laser light source, or an LED light source is used. be able to.

  Although the temperature in the case of heating can be suitably adjusted with the kind etc. of the polymerization initiator in curable resin composition, 40-200 degreeC is mentioned.

  In addition, when curable resin composition contains an organic solvent etc., you may give the drying process for volatilizing an organic solvent etc. before hardening. The drying conditions are not particularly limited and may be appropriately selected according to the type and amount of the organic solvent. Examples of the drying conditions include a condition of 60 to 200 ° C. for 1 to 30 minutes.

  In addition, the cured resin according to the present invention is a reactive diluent having a radical polymerizable double bond and a radical polymerizable group that the curable resin of the present embodiment has, as long as the effects of the present invention are not impaired. Polymers with other monomers and resins (for example, thermosetting resins) may be used.

  Next, the fiber sizing agent according to the present invention will be described. The fiber sizing agent of this embodiment contains the curable resin of this embodiment.

  The method for obtaining the fiber sizing agent of this embodiment is not particularly limited. For example, the method of using the curable resin of this embodiment as a sizing agent as it is, or the curable resin of this embodiment in an organic solvent or water. Examples of the sizing agent include adding, mixing and stirring to disperse and dissolve. From the viewpoint of better handling, a method of forming a sizing agent by dispersing and dissolving the curable resin of this embodiment in water or an organic solvent is preferable.

  Examples of the organic solvent include lower alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; glycols or glycol ethers such as ethylene glycol, propylene glycol, ethylene glycol monoisopropyl ether, and ethylene glycol monobutyl ether; acetone, methyl ethyl ketone, and the like. Ketones, acetonitrile, N, N-dimethylformamide, nitrogen-containing compounds such as aniline, toluene and the like can be used.

  Moreover, components other than water and an organic solvent can also be added to the fiber sizing agent of the present embodiment as long as the effects of the present invention are not impaired. Examples include various surfactants, various smoothing agents, antioxidants, flame retardants, antibacterial agents, and antifoaming agents. These additive components may be used individually by 1 type, and may be used in combination of 2 or more type.

  In particular, when the fiber sizing agent of this embodiment contains water as a solvent or a dispersion medium, a surfactant can be used as an emulsifier, and emulsification of the curable resin or the like of this embodiment can be efficiently performed. .

  Although content of the curable resin of this embodiment in the sizing agent for fibers can be appropriately adjusted, for example, it can be 0.1 to 100% by mass based on the total amount of the sizing agent for fibers.

  The type of fiber to which the fiber sizing agent can be applied is not particularly limited as long as it is a chemical fiber or a natural fiber such as an inorganic fiber or an organic fiber used in a fiber-reinforced composite material. For example, carbon fiber, Various inorganic fibers such as basalt fiber, glass fiber, ceramic fiber, aramid fiber, polyethylene fiber, polyethylene terephthalate fiber, polybutylene terephthalate fiber, polyethylene naphthalate fiber, polyarylate fiber, polyacetal fiber, PBO fiber, polyphenylene sulfide fiber, polyketone fiber And various natural fibers such as hemp fibers such as jute and kenaf, bamboo fibers and cotton fibers.

  Next, the reinforcing fiber according to the present invention will be described.

  The reinforcing fiber of the present embodiment includes a fiber and the curable resin of the present embodiment described above attached to the fiber.

  The reinforcing fiber of this embodiment can be obtained by treating the above-described fiber with the above-described fiber sizing agent. For example, the fiber is brought into contact with the fiber sizing agent of this embodiment. Thereby, the curable resin of this embodiment can be made to adhere to a fiber.

  The method for bringing the fibers into contact with the fiber sizing agent is not particularly limited, and known methods can be used, and examples thereof include a kiss roller method, a roller dipping method, a spray method, and a Dip method.

  In contact with the fiber, the fiber sizing agent may be brought into contact with the fiber as it is, or a treatment liquid containing the fiber sizing agent may be prepared, and the treatment liquid may be brought into contact with the fiber. As a density | concentration of the sizing agent for fibers in a process liquid, the density | concentration from which the density | concentration of curable resin of this embodiment will be 0.5-60 mass% is mentioned. Moreover, the above-mentioned organic solvent, water, etc. are mentioned as a solvent used for a process liquid.

  There is no restriction | limiting in particular in the drying method after contact, For example, with a heating roller, a hot air, a hot plate etc., it is 10 seconds-10 minutes at the temperature of 90-300 degreeC, More preferably, it is 30-second at the temperature of 100-250 degreeC. The method etc. which heat-dry for 4 minutes are mentioned.

  The adhesion amount of the fiber sizing agent to the fiber can be selected as appropriate, but the adhesion amount of the curable resin of this embodiment is preferably 0.05 to 10% by mass based on the mass of the fiber. The amount of 1 to 5% by mass is more preferable.

  Among the above-described chemical fibers and natural fibers, the fibers are preferably carbon fibers from the viewpoint of improving the adhesion. The form of the carbon fiber is not particularly limited, and examples thereof include a bundle of several thousand to several tens of thousands of known carbon fiber filaments such as polyacrylonitrile (PAN), rayon, or pitch. In this embodiment, it is preferable to attach the fiber sizing agent of this embodiment to a bundle of carbon fibers that have been sufficiently carbonized through a heat carbonization treatment. As such a carbon fiber, it is more preferable that 90 mass% or more is comprised with carbon.

  The form of the reinforcing fiber of the present embodiment is not particularly limited, and examples thereof include bundles, woven fabrics, knitted fabrics, braids, webs, mats, and choppeds, and can be appropriately selected depending on the purpose and usage method.

  The reinforcing fiber of this embodiment can be used to obtain a fiber-reinforced composite material using a thermosetting resin as a matrix resin.

  Next, the resin composition for forming a fiber reinforced composite material and the fiber reinforced composite material according to the present invention will be described.

  The resin composition for forming a fiber reinforced composite material of the present embodiment includes the reinforcing fiber of the present embodiment and a thermosetting resin. The thermosetting resin may be uncured or partially cured.

  There is no restriction | limiting in particular as a thermosetting resin, The thing conventionally used as a matrix resin of a fiber reinforced composite material can be used. Examples include epoxy resins, radical polymerizable resins, phenol resins, melamine resins, urea resins, cyanate ester resins, and bismaleimide resins. Especially, it is preferable that it is a radically polymerizable resin from a viewpoint that adhesiveness is more excellent.

  Examples of the radical polymerizable resin include a resin having a radical polymerizable double bond in the molecule. Among these, unsaturated polyester resins and vinyl ester resins are preferable from the viewpoint of better adhesion.

  Examples of unsaturated polyester resins include resins obtained by polycondensation of α, β-unsaturated dicarboxylic acids or acid anhydrides thereof with glycols, and include aromatic saturated dicarboxylic acids or acid anhydrides, aliphatic or fatty acids. Both cyclic saturated dicarboxylic acids may be polycondensed.

  Examples of the unsaturated dicarboxylic acid or its acid anhydride include maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, chloromaleic acid, and esters thereof.

  As glycols, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 2-methylpropane-1,3-diol, neopentyl glycol, triethylene glycol, Tetraethylene glycol, 1,5-pentanediol, 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, ethylene glycol carbonate, 2,2-di- (4-hydroxypropoxydiphenyl) propane and their carbon number of 2 -4 alkylene oxide adducts and the like.

  Aromatic saturated dicarboxylic acids or acid anhydrides thereof include phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, nitrophthalic acid, tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, halogenated phthalic anhydride and esters thereof. Etc.

  Examples of the aliphatic or alicyclic saturated dicarboxylic acid include oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, glutaric acid, hexahydrophthalic anhydride, and esters thereof.

  Examples of the vinyl ester resin include those obtained by esterifying an epoxy compound and an α, β-unsaturated monocarboxylic acid.

  Examples of the epoxy compound include a bisphenol type epoxy compound, an amine type epoxy compound, a novolac type epoxy compound, and a resorcinol type epoxy compound. Examples of bisphenol type epoxy compounds include those obtained by reaction of bisphenol compounds with epichlorohydrin. Examples of bisphenol compounds include bisphenol A, bisphenol F, bisphenol AD, bisphenol S, or their halogeno, alkyl-substituted products, hydrogenated products. Etc. Moreover, not only a monomer but the polymer which has a some repeating unit can also be used. Examples of the amine type epoxy compound include tetraglycidyldiaminodiphenylmethane, triglycidylaminophenol, triglycidylaminocresol, tetraglycidylxylylenediamine, halogeno, alkynol-substituted products, and hydrogenated products thereof. Examples of the novolak type epoxy compound include a reaction product of phenol novolak or cresol novolak and epichlorohydrin. Examples of the resorcinol type epoxy compound include a reaction product of resorcinol or a halogeno thereof, an alkyl-substituted product and epichlorohydrin.

  Examples of the unsaturated monocarboxylic acid include (meth) acrylic acid, cinnamic acid, crotonic acid, monomethyl malate, sorbic acid, mono (2-ethylhexyl) malate, and the like.

  The fiber-reinforced composite material-forming resin composition can be blended into the thermoplastic resin, elastomers and fillers for modifying the matrix resin, rubber particles, inorganic particles, and the curable resin composition described above, if necessary. The illustrated polymerization initiator, curing accelerator, organic solvent for adjusting viscosity, reactive diluent, and the like may be included.

  It is preferable that the polymerization initiator is blended immediately before molding or curing the resin composition for forming a fiber reinforced composite material. Although the compounding quantity of a polymerization initiator can be adjusted suitably, it can be 0.01-15 mass parts with respect to 100 mass parts of thermosetting resins, for example, Preferably it is 0.05-10 mass parts.

  The fiber-reinforced composite material is obtained by molding the resin composition for forming a fiber-reinforced composite material of the present embodiment into a predetermined shape according to the purpose and curing it.

  The molding method of the resin composition for forming the fiber reinforced composite material is not particularly limited. For example, the impregnation method, the pultrusion method (pultrusion), the hand layup method, the RTM method, the vacuum impregnation method (VaRTM), the filament winding method, and the like The method is mentioned. Of these, the hand lay-up method and the vacuum impregnation method are preferable.

  The resin composition for forming a fiber reinforced composite material of this embodiment may be a prepreg obtained by impregnating the reinforcing fiber of this embodiment with a thermosetting resin. Examples of the method for producing the prepreg include a wet method in which a thermosetting resin is dissolved in a solvent such as methyl ethyl ketone and methanol to lower the viscosity and impregnated, or a hot melt method in which the viscosity is lowered by heating and impregnated.

  In the wet method, after reinforcing fibers are immersed in a liquid containing a thermosetting resin, the prepreg can be obtained by pulling up and evaporating the solvent using an oven or the like. Also, in the hot melt method, a method of directly impregnating a reinforcing fiber with a thermosetting resin whose viscosity has been reduced by heating, or a film in which a thermosetting resin is once coated on release paper or the like is first created and then reinforced. A prepreg can be produced by a method in which the film is overlapped from both sides or one side of the reinforcing fiber and heated and pressed to impregnate the reinforcing fiber with the thermosetting resin.

  The content of the reinforcing fiber in the fiber-reinforced composite material-forming resin composition can be appropriately adjusted depending on the molding method, the use of the fiber-reinforced composite material, etc., for example, based on the total mass of the thermosetting resin and the reinforcing fiber In the case of a prepreg, 40 to 90% by mass is preferable.

  The fiber-reinforced composite material of the present embodiment includes a cured product of the above-described resin composition for forming a reinforcing fiber composite material.

  The fiber reinforced composite material of this embodiment can be manufactured by hardening | curing the resin composition for reinforcing fiber composite material formation, for example. In this step, the thermosetting resin in the fiber-reinforced composite material-forming resin composition and the curable resin of the present embodiment on the reinforcing fiber can be cured by a radical polymerization reaction. Examples of the curing method include the curing methods described above as a method for curing the curable resin composition of the present embodiment.

  Moreover, as a manufacturing method of the fiber reinforced composite material when taking the form of a prepreg as a resin composition for forming a fiber reinforced composite material, a method of heating and curing while applying pressure to the laminate after the prepreg is laminated is used. The curable resin of this embodiment on the thermosetting resin in the prepreg and the reinforcing fiber is heat-cured to form a fiber-reinforced composite material.

  Examples of methods for applying heat and pressure include a pressing method, an autoclave method, a bagging method, a wrapping tape method, and an internal pressure molding method.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited to these examples.

<Manufacture of curable resin>
Example 1
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, an air gas introduction pipe and a dropping funnel, 680 parts by mass of a bisphenol A type epoxy compound represented by the following formula (i), and triphenylphosphine as an addition reaction catalyst 5 parts by mass and 1 part by mass of methylhydroquinone as a radical polymerization inhibitor were added. 296 mass parts of acrylic acid was dripped here, it was made to react at 110 degreeC, and the compound B-1 represented by following formula (ii) was obtained.

［式（５−１）中、ｅ１は１８〜２８の整数を表す。］ 22.6 parts by mass of compound B-1 represented by formula (ii), 7.9 parts by mass of hexamethylene diisocyanate, 10.4 parts by mass of isophorone diisocyanate, both represented by the following formula (5-1) 56 parts by mass of polydimethylsiloxane having a hydroxy group at the terminal (weight average molecular weight 2000) (hereinafter referred to as “hydroxyl-terminated polysiloxane (molecular weight 2000)”), 100 parts by mass of methyl ethyl ketone, urethane reaction catalyst (manufactured by Nitto Kasei Co., Ltd.) , Product name: Neostan U-600 (bismuth-based catalyst)) and 0.1 part by mass of radical polymerization inhibitor (methylhydroquinone) are mixed and reacted at 80 ° C. to give 1,4 butane 1.8 parts by mass of diol was added and reacted until the isocyanate group disappeared to obtain a methyl ethyl ketone solution of a curable resin.

[In formula (5-1), e1 represents the integer of 18-28. ]

(Examples 2 to 11 and Comparative Examples 1 to 5)
A curable resin was obtained in the same manner as in Example 1 except that the raw material composition was changed as shown in Tables 1 to 4.

  In addition, the following notation in a table | surface is demonstrated below.

“B-2”: a compound represented by the following formula (iv) produced by the following procedure.

  In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, an air gas introduction pipe and a dropping funnel, 1816 parts by mass of a bisphenol A type epoxy compound represented by the following formula (iii), and triphenylphosphine as an addition reaction catalyst 10 parts by mass and 2 parts by mass of methylhydroquinone as a radical polymerization inhibitor were added. 296 mass parts of acrylic acid was dripped here, it was made to react at 110 degreeC, and the compound B-2 represented by a following formula (iv) was obtained.

［式（５−２）中、ｅ２は２８〜３８の整数を表す。］ “Hydroxyl terminal polysiloxane (molecular weight 3200)”: Polydimethylsiloxane having a hydroxy group at both ends (weight average molecular weight 3200) represented by the following general formula (5-2).

[In formula (5-2), e2 represents the integer of 28-38. ]

［式（５−３）中、ｅ３は２３〜３３の整数を表す。］ “Hydroxyl terminal polysiloxane-2 (molecular weight 3200)”: Polydimethylsiloxane (weight average molecular weight 3200) having hydroxy groups at both ends represented by the following general formula (5-3).

[In formula (5-3), e3 represents an integer of 23 to 33. ]

“B ′”: a compound represented by the following formula (v).

“PPG (molecular weight 2000)”: polypropylene glycol (weight average molecular weight 2000).

[Evaluation of self-healing]
40 parts by mass of the curable resin obtained in Examples 1 to 11 and Comparative Examples 1 to 5 and 2 parts by mass of a photopolymerization initiator (1-hydroxycyclohexyl phenyl ketone) were mixed to obtain a curable resin composition. . The obtained curable resin composition was applied to a polyester film using an applicator and dried at 80 ° C. for 10 minutes to form a film-like curable resin composition having a film thickness of about 100 μm. The film-shaped curable resin composition was irradiated with ultraviolet rays (UVC waves) so as to have an irradiation amount of 500 mJ / cm ² to obtain a film-shaped resin cured product. The obtained film-shaped resin cured product was subjected to a rubbing treatment with a brass brush at a load of 100 g / cm ² in the same place three times in one direction. The haze value of the place subjected to the rubbing treatment was measured using a fully automatic direct reading haze computer HGM-2DP (manufactured by Suga Test Instruments Co., Ltd.) before and after being left to stand for 1 day after the rubbing treatment. The difference was calculated. The results are shown in Tables 1-3. If the difference is 4 or less, the self-repairing property is excellent.

  In addition, in the resin cured products of Examples 1 to 11, the scratches due to the rubbing treatment were repaired so that they could not be visually confirmed in 3 minutes at the latest after the rubbing treatment. Since some scratches required one day to repair the value to the extent that measurement was possible, a one-day standing time was provided after the rubbing treatment.

<Manufacture of reinforcing fibers>
(Examples 12 to 22 and Comparative Examples 6 to 10)
First, carbon fiber for composite material (Mitsubishi Rayon Co., Ltd., product name: TR50S15L) was washed with acetone to remove the sizing agent, and carbon fiber was obtained.

  Next, the curable resins prepared in Examples 1 to 11 and Comparative Examples 1 to 5 were each dissolved in acetone to prepare a sizing agent having a curable resin concentration of 10% by mass. Next, the carbon fiber was immersed in a sizing agent, taken out, squeezed, and dried with hot air at 80 ° C. for 30 minutes to obtain a reinforcing fiber. The adhesion amount of the curable resin in the reinforcing fiber was 1.5% by mass of the carbon fiber.

(Comparative Example 11)
A reinforcing fiber was obtained in the same manner as described above except that 2,2-bis (4-hydroxyphenyl) propanediglycidyl ether was used instead of the curable resin.

[Evaluation of adhesion]
Using a composite material interface property evaluation apparatus HM410 (manufactured by Toei Sangyo Co., Ltd.), adhesiveness was evaluated by a microdroplet method.

A single fiber was taken out from the reinforcing fibers of Examples 12 to 22 and Comparative Examples 6 to 10, set in a sample holder, and a resin ball (drop) of the following uncured matrix resin was formed on the single fiber. It was left to stand for 24 hours, and then cured by heating at 60 ° C. for 1 hour and at 100 ° C. for 3 hours to prepare a test piece.
(Matrix resin)
100 parts by mass of unsaturated polyester resin (manufactured by Japan Composite Co., Ltd., product name: Polypop R-1000AP), 0.5 parts by mass of 6% by mass cobalt naphthenate (manufactured by Showa Chemical Co., Ltd.), methyl ketone peroxide 1 mass part mixed

Next, the test piece is set in the apparatus, the drop is sandwiched between the apparatus blades, the single fiber is run on the apparatus at a speed of 0.06 mm / min, and the maximum extraction load F when the drop is extracted from the single fiber is measured. The interfacial shear strength τ was calculated from the following formula. The results are shown in Tables 1-3. The larger the interfacial shear strength, the better the adhesion between the single fiber and the matrix resin.
(Interfacial shear strength τ (MPa) calculation formula)
τ = F / πDL
[F: Maximum pulling load (N), D: Single fiber diameter (m), L: Particle diameter in the pulling direction of the drop (m)]

  As shown in Tables 1 to 4, the cured resin products of Examples 1 to 11 obtained by curing the curable resin composition containing the curable resin according to the present invention have excellent self-healing properties. I understood. Moreover, it turned out that the reinforcing fiber of Examples 12-22 has the outstanding adhesiveness with matrix resin.

  ADVANTAGE OF THE INVENTION According to this invention, the sizing agent for fibers which can obtain the fiber for reinforcement excellent in adhesiveness with a matrix resin, the curable resin and curable resin composition which can be used for it can be provided. According to the fiber sizing agent of the present invention, it is possible to impart excellent adhesion to a thermosetting resin, particularly a radical polymerizable resin, to the fiber, and to reinforce having excellent adhesion to the thermosetting resin. A fiber and a fiber-reinforced composite material using the reinforcing fiber can be obtained. The obtained fiber reinforced composite material is useful for parts and members such as automobiles, airplanes, and sporting goods.

Claims (9)

An isocyanate group-terminated prepolymer obtained by reacting (A) a polyisocyanate, (B) a compound represented by the following general formula (1-1), and (C) a polysiloxane having at least two hydroxy groups; ,
(D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) a hydroxyalkyl (meth) represented by the following general formula (2) At least one compound selected from the group consisting of acrylates;
A curable resin obtained by reacting.

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ] An isocyanate group-terminated prepolymer obtained by reacting (A) a polyisocyanate, (B) a compound represented by the following general formula (1-1), and (C) a polysiloxane having at least two hydroxy groups; ,
(D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) a hydroxyalkyl (meth) represented by the following general formula (2) At least one compound selected from the group consisting of acrylates;
Reacting with
A method for producing a curable resin.

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ]   A curable resin composition comprising the curable resin according to claim 1.   A cured resin, which is a cured product of the curable resin composition according to claim 3.   A sizing agent for fibers containing the curable resin according to claim 1.   A reinforcing fiber comprising a fiber and the curable resin according to claim 1 attached to the fiber.   A resin composition for forming a fiber-reinforced composite material, comprising the reinforcing fiber according to claim 6 and a thermosetting resin.   The fiber reinforced composite material containing the hardened | cured material of the resin composition for reinforcing fiber composite material formation of Claim 7.   The manufacturing method of a fiber reinforced composite material provided with the process of hardening | curing the resin composition for reinforcing fiber composite material formation of Claim 7.