WO2019142803A1

WO2019142803A1 - Matrix resin, intermediate material, and molded article

Info

Publication number: WO2019142803A1
Application number: PCT/JP2019/001017
Authority: WO
Inventors: 隼人小笠原; 征司土屋; 小並　諭吉; 洋之中尾; 鍋島　泰彦
Original assignee: 三菱ケミカル株式会社
Priority date: 2018-01-16
Filing date: 2019-01-16
Publication date: 2019-07-25
Also published as: JP6791354B2; JPWO2019142803A1

Abstract

The present invention provides a matrix resin that allows a broader processing window. This matrix resin includes at least a mixture of components (A-1) to (A-4). The (A-1) component is an unsaturated polyester resin and an epoxy (meth)acrylate resin having one or more ethyleny unsaturated groups in a molecule and having an average number of hydroxyl groups of 1.8 to 4. The (A-2) component is an ethyleny unsaturated monomer. The (A-3) component is polyisocyanate where the content of isocyanate group is 15 to 30.5 mass%, and the average number of isocyanate groups is 1.8 to 2.4. The (A-4) component is a thermal polymerization initiator.

Description

Matrix resin, intermediate materials and molded products

The present invention relates to a matrix resin, an intermediate material and a molded article.
Priority is claimed on Japanese Patent Application No. 2018-004833, filed January 16, 2018, the content of which is incorporated herein by reference.

Fiber-reinforced composite materials containing reinforcing fibers, fillers, etc. are excellent in mechanical strength, in addition to ease of processing, non-corrosion, and lightness, which are characteristics of plastics, and therefore members for electrical and electronic devices, building materials, vehicles It is widely used for the member etc.
Fiber reinforced composites are manufactured in a variety of ways. For example, a method of laminating a prepreg in which a matrix resin is impregnated in advance on a reinforcing fiber base made of continuous fibers, and heat curing the resin for molding is widely used. However, molding using a prepreg makes it difficult to produce a fiber-reinforced composite material of complicated shape having fine irregularities.

For the production of a fiber-reinforced composite material having a complex shape having fine irregularities, an intermediate material in which a reinforcing resin cut into a predetermined length is impregnated with a matrix resin in advance is suitable. Since the intermediate material easily flows in the mold at the time of molding, it can be applied to the formation of fine asperities.
As the intermediate material, for example, those containing a reinforcing fiber cut into a fixed length and a thermosetting resin such as an unsaturated polyester resin, an epoxy (meth) acrylate resin, etc. are known (Patent Documents 1 to 4).

Thickeners are often blended into matrix resins for the purpose of improving handleability. When the thermosetting resin in the matrix resin contains an unsaturated polyester resin or an epoxy (meth) acrylate resin, generally, as a thickener, an alkaline earth metal salt such as MgO or CaO or a metal hydrate thereof; An isocyanate type thickener etc. are used. Among these, it is known that when an isocyanate-based thickener is used, the resin can be easily thickened and the handling property and the like is improved (Patent Documents 5 to 7).
Patent Document 7 describes a prepreg having a specific urethane-modified epoxy (meth) acrylate as an essential component. A specific urethane-modified epoxy (meth) acrylate is a reaction product of an epoxy (meth) acrylate having an average number of hydroxyl groups per molecule in a specific range and a polyisocyanate having an average number of isocyanate groups per molecule in a specific range is there.

JP 11-147222 A Unexamined-Japanese-Patent No. 10-110048 JP 10-120736 A Japanese Patent Application Laid-Open No. 11-147221 Japanese Examined Patent Publication No. 60-24810 Japanese Examined Patent Publication 63-1332 Patent No. 6150034

However, when thickening an unsaturated polyester resin, an epoxy (meth) acrylate resin, etc. with an isocyanate type thickener, the responsiveness of the hydroxyl group which these thermosetting resins have, and an isocyanate type thickener is sharp. Therefore, the range (that is, process window) of the compounding ratio of the thermosetting resin and the isocyanate-based thickener which can balance the handleability and the fluidity of the intermediate material tends to be narrow. That is, the fluidity of the intermediate material may be greatly reduced or the handleability may be greatly deteriorated, as compared with the numerical value of the optimum ratio, by merely increasing or decreasing the compounding amount of the isocyanate-based thickener. As a result, product unevenness of the intermediate material may occur due to an increase or decrease in the compounding amount of the isocyanate-based thickener.

As in the case of the prepreg described in Patent Document 7, the process window can not always be expanded simply by setting the average number of functional groups per molecule of the epoxy (meth) acrylate resin and the isocyanate-based thickener to a specific range. In addition, the ripening period may be excessively prolonged. Furthermore, in the case of blending an epoxy (meth) acrylate resin and a solid isocyanate-based thickener, the epoxy (meth) acrylate resin contacts with a high concentration until the isocyanate-based thickener dissolves, so in the three-dimensional direction There is a concern that a thickening reaction of the above may be induced, and product spots on the intermediate material may occur. Therefore, in the prepreg described in Patent Document 7, there is a possibility that mechanical properties and heat resistance of a molded article may be reduced.

The present invention has been made in view of the above circumstances, and provides a matrix resin which can widen the process window; an intermediate material having a wide process window and little product unevenness; and a molded article having excellent mechanical properties and heat resistance. With the goal.

The inventors of the present invention conducted intensive studies to solve the above problems, and as a result, the number of hydroxyl groups per molecule of epoxy (meth) acrylate resin and unsaturated polyester resin, and isocyanate per molecule of isocyanate-based thickener. By setting the group content rate and the number of isocyanate groups within a specific range, an intermediate material having a wide process window and few product spots, and a molded article excellent in mechanical properties and heat resistance have been found, and the present invention has been completed.

The present invention has the following aspects.
[1] A matrix resin containing at least a mixture of the following components (A-1) to (A-4):
(A-1) Component: Both an epoxy (meth) acrylate resin and an unsaturated polyester resin having one or more ethylenically unsaturated groups in one molecule and having an average number of hydroxyl groups of 1.8 to 4.
Component (A-2): Ethylenically unsaturated monomer.
Component (A-3): polyisocyanate having an isocyanate group content of 15 to 30.5% by mass and an average number of isocyanate groups of 1.8 to 2.4.
Component (A-4): thermal polymerization initiator.
[2] A matrix resin of [1] which satisfies the following formulas (1) to (4).
5 ≦ V 1 _X ≦ 40 (1)
Y ≧ 0.5 (2)
5 ≦ V1 _{X + Y} ≦ 70 (3)
5 ≦ V1 _XY ≦ 70 (4)
Matrix resin in which V1 _X is a reference amount X (parts by mass) with respect to 100 parts by mass of a thermosetting resin consisting of a component having an ethylenically unsaturated group in the formula (1). Is left to stand at 23 ° C. for 168 hours, and the viscosity is [× 10 ⁶ mPa · s], and the reference amount X is 10 to 40 parts by mass.
In the formula (2), Y is a difference [mass part] to increase or decrease the blending amount of the component (A-3) with respect to the reference amount X in the formula (1).
In the formula (3), V1 _{X + Y} is a matrix resin in which the blending amount of the component (A-3) is increased relative to the reference amount X in the formula (1) by the amount of difference Y in the formula (2) [parts by mass] The resulting solution had a ripening viscosity [× 10 ⁶ mPa · s] when allowed to stand at 23 ° C. for 168 hours.
In the formula (4), V1 _XY decreased the blending amount of the component (A-3) with respect to the reference amount X in the formula (1) by the difference amount Y [parts by mass] in the formula (2) It is the ripening viscosity [× 10 ⁶ mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 168 hours.
[3] The matrix resin of [1] or [2], which satisfies the following formula (5) and the following formula (6).
5 ≦ V1 ≦ 40 (5)
V2 / V1 ≦ 2.5 (6)
In Formula (5), V1 is the aging viscosity [× 10 ⁶ mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 168 hours.
In the formula (6), V1 is the same as V1 in the formula (5), and V2 is a ripening viscosity [× 10 ⁶ mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 336 hours.
[4] The matrix resin according to any one of [1] to [3], wherein the liquid polyisocyanate has one or more aromatic rings in the molecule.
[5] The matrix resin according to any one of [1] to [4], which satisfies the following formula (7) and the following formula (8).
0.6 ≦ a1 / b ≦ 0.75 (7)
Vn ≦ 1000 (8)
In the formula (7), a1 is the content [g] of the component (A-1), and b is the content [g] of the thermosetting resin composed of the component having an ethylenically unsaturated group.
In Formula (8), Vn is a neat resin viscosity [mPa · s] of a thermosetting resin comprising a component having an ethylenically unsaturated group.
[6] The matrix resin according to any one of [1] to [5], which satisfies the following formula (9).
V10 / Vs ≦ 1.20 (9)
In formula (9), Vs is the viscosity [mPa · s] immediately after mixing the pre-matrix resin obtained by removing the component (A-3) from the matrix resin and the component (A-3), and V10 is the above-mentioned It is a viscosity [mPa · s] when 10 minutes have elapsed by mixing the pre-matrix resin and the component (A-3).
[7] An intermediate material comprising the matrix resin of any one of [1] to [6] and a carbon fiber bundle having a fiber length of 5 to 120 mm.
[8] A molded article obtained by heat and pressure molding the intermediate material of [7].
[9] The molded article according to [8], wherein the temperature at which the loss tangent measured by dynamic viscoelasticity measurement at a frequency of 1 Hz shows a maximum value is 120 ° C. or higher.

According to the present invention, it is possible to provide a matrix resin capable of widening a process window, an intermediate material having a wide process window and little product unevenness at the time of production, and a molded article having excellent mechanical properties and heat resistance.

In the present specification, "the process window of the matrix resin is wide" means that the numerical range of the ratio of the blending amount of the polyisocyanate to the matrix resin is sufficiently wide, which satisfies the following requirement (I).
Requirement (I): The viscosity of the matrix resin after thickening contained in the intermediate material when the matrix resin is used as the intermediate material is in an appropriate range, and the intermediate material is provided with tackiness and drapability suitable for handling. At the same time, it should be able to develop a state having sufficient fluidity at the time of molding.
The "polymerizable unsaturated monomer" is a monomer having a polymerizable unsaturated group.
"(Meth) acrylate" is a generic term for acrylate or methacrylate, and "epoxy (meth) acrylate" is a generic term for epoxy acrylate or epoxy methacrylate.
The "isocyanate group content" means the mass of isocyanate group per 100 g of polyisocyanate.
The "average number of isocyanate groups" means the average value of the number of isocyanate groups per polyisocyanate molecule.
“Viscosity” is a value measured at a rotor rotational speed of 60 rpm using TB-10 (manufactured by Toki Sangyo Co., Ltd.) equipped with an M3 rotor under a 23 ° C. environment.
The "carbon fiber content" means the content of carbon fiber with respect to 100% by mass of the intermediate material.
“-” Indicating a numerical range means that numerical values described before and after that are included as the lower limit value and the upper limit value.
"Making the matrix resin at a substantially constant temperature for a certain period of time" may be referred to as "aging" or "thickening".

<Matrix resin>
The matrix resin of the present invention contains at least a mixture of the following components (A-1) to (A-4). The matrix resin of the present invention may contain the following component (A-5).
(A-1) Component: Both an epoxy (meth) acrylate resin and an unsaturated polyester resin having one or more ethylenically unsaturated groups in one molecule and having an average number of hydroxyl groups of 1.8 to 4.
Component (A-2): Ethylenically unsaturated monomer.
Component (A-3): Liquid polyisocyanate having an isocyanate group content of 15 to 30.5% by mass and an average number of isocyanate groups of 1.8 to 2.4.
Component (A-4): thermal polymerization initiator.
Component (A-5): a compound other than the components (A-1) and (A-2), having no hydroxyl group and having an ethylenically unsaturated group.

The matrix resin of the present invention contains a thermosetting resin which is a mixture of the (A-1) component and the (A-2) component. When the matrix resin contains the component (A-5), the thermosetting resin is a mixture of the components (A-1), (A-2) and (A-5). That is, in the matrix resin of the present invention, the thermosetting resin comprises a component having an ethylenically unsaturated group.
The matrix resin of the present invention may contain other components in addition to the components (A-1) to (A-5).

[(A-1) component]
The matrix resin of the present invention contains both an epoxy (meth) acrylate resin and an unsaturated polyester resin as the component (A-1).
The matrix resin of the present invention may contain one or more of each of an epoxy (meth) acrylate resin and an unsaturated polyester resin.

(Epoxy (meth) acrylate resin)
In the matrix resin of the present invention, the epoxy (meth) acrylate resin has one or more ethylenically unsaturated groups in one molecule, and is not particularly limited as long as the average number of hydroxyl groups is 1.8 to 4. For example, an epoxy (meth) acrylate resin can be obtained as a reaction product of an epoxy resin and an unsaturated monobasic acid (unsaturated acid epoxy ester).

As epoxy resin, diglycidyl ether type epoxy resin whose main skeleton is bisphenol A represented by bisphenol A, bisphenol F, and brominated bisphenol A; organic polybasic acid represented by dimer acid and trimellitic acid Polyglycidyl ester type epoxy resin, ethylene oxide or propylene oxide adduct of bisphenol A, glycol, glycidyl ether type epoxy resin having a diol compound such as hydrogenated bisphenol A as main skeleton, phenol novolac, cresol novolac, brominated phenol The novolak-type epoxy resin etc. which made the main skeleton the polynuclear phenol compound represented by the novolak are illustrated. These epoxy resins may be used alone or in combination of two or more.
Among them, epoxy (meth) acrylate resins using an epoxy resin having 1 to 4 bisphenol A skeletons in one molecule have a two-dimensional reaction preferentially at the time of the thickening reaction with the component (A-3). It is preferable because the process window of the matrix resin and the intermediate material can be further expanded. In particular, an epoxy (meth) acrylate containing an epoxy resin having one or two bisphenol A skeletons as a main component can suppress the neat resin viscosity when the component (A-2) is blended. As a result, for example, when manufacturing an intermediate material having a high content of carbon fiber bundles, the quality tends to be easily maintained.

An unsaturated monobasic acid is a monobasic acid having an ethylenically unsaturated group. Examples of unsaturated monobasic acids include acrylic acid, methacrylic acid, crotonic acid and sorbic acid. These unsaturated monobasic acid components may be used alone or in combination of two or more.

In the present invention, the epoxy (meth) acrylate resin has a hydroxyl group produced when the unsaturated monobasic acid is reacted or a hydroxyl group originally possessed by the epoxy resin. In addition to the above hydroxyl groups, the number of hydroxyl groups can be adjusted by a conventionally known method at the time of synthesis of the epoxy (meth) acrylate resin or after synthesis of the epoxy (meth) acrylate resin.
The number of ethylenically unsaturated groups that the epoxy (meth) acrylate resin has in one molecule is 1.0 or more, preferably 1.5 or more. Moreover, 5.0 or less is preferable, as for the number of the said ethylenically unsaturated groups, 3.0 or less is more preferable, and 2.5 or less is more preferable. When the number of the ethylenically unsaturated groups is in the above range, the curability, solvent resistance, heat resistance, mechanical properties and the like of the molded article of the present invention described later are further excellent.
The number of ethylenically unsaturated groups that the epoxy (meth) acrylate resin has in one molecule is preferably 1.0 to 5.0, more preferably 1.5 to 5.0, and 1.5 to 3.0. More preferably, 1.5 to 2.5 are particularly preferred.

The average number of hydroxyl groups, which is the average of the number of hydroxyl groups that the epoxy (meth) acrylate resin has in one molecule, is 1.8 or more, preferably 2.8 or more. When the average number of hydroxyl groups is 1.8 or more, the tackiness and the drapability of the obtained intermediate material become good.
The average number of hydroxyl groups is 4 or less, preferably 3.8 or less. When the average number of hydroxyl groups is 4 or less, the thickening reaction between the component (A-1) and the component (A-3) preferentially occurs in the two-dimensional direction, and the reaction in the three-dimensional direction is suppressed. As a result, the handleability and fluidity of the obtained intermediate material are excellent.
The average number of hydroxyl groups in one molecule of the epoxy (meth) acrylate resin is preferably 1.8 to 3.8, and more preferably 2.8 to 3.8.

(Unsaturated polyester resin)
In the matrix resin of the present invention, the unsaturated polyester resin has one or more ethylenically unsaturated groups in one molecule, and is not particularly limited as long as the average number of hydroxyl groups is 1.8 to 4. For example, an unsaturated polyester resin is a polyester resin synthesized by condensation of an α, β-olefin unsaturated dicarboxylic acid and a divalent glycol (a weight of an α, β-olefin unsaturated dicarboxylic acid and a divalent glycol It can be obtained as a condensate). The polyester resin is derived from an α, β-olefin unsaturated dicarboxylic acid, has an ethylenically unsaturated group, and has a hydroxyl group.
In the synthesis of the polyester resin, in addition to these two components, dicarboxylic acids other than α, β-olefin unsaturated dicarboxylic acids (saturated dicarboxylic acids, aromatic dicarboxylic acids, etc.), dicyclopentadiene reactive with dicarboxylic acids, Alcohols other than dihydric glycols (monohydric alcohols (monools), trihydric alcohols (triols, etc.), etc.) can be used in combination.

Examples of the α, β-olefin unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and anhydrides of these dicarboxylic acids.
Other dicarboxylic acids that can be used in combination with the α, β-olefin unsaturated dicarboxylic acid include adipic acid, sebacic acid, succinic acid, gluconic acid, phthalic acid anhydride, o-phthalic acid, isophthalic acid, terephthalic acid, tetrahydrofuran Phthalic acid, tetrachlorophthalic acid and the like are exemplified.
Examples of divalent glycols include alkane diols, oxa alkane diols, and alkylene oxide adducts of bisphenol A. Ethylene oxide, a propylene oxide etc. are illustrated as an alkylene oxide.
As the alkanediol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyglycol, 1,5-pentanediol, 1,6 -Hexanediol, cyclohexanediol, etc. are exemplified.
Examples of oxaalkanediols include dioxyethylene glycol, dipropylene glycol and triethylene glycol.
Examples of monohydric or trihydric alcohols that can be used in combination with glycols include octyl alcohol, oleyl alcohol, trimethylolpropane and the like.

The number of ethylenically unsaturated groups that the unsaturated polyester resin has in one molecule is 1.0 or more, preferably 1.5 or more. Moreover, 5.0 or less is preferable and, as for the number of the said ethylenically unsaturated groups, 3.0 or less is more preferable. When the number of the ethylenically unsaturated groups is in the above range, the curability, solvent resistance, heat resistance, mechanical properties and the like of the molded article of the present invention described later are further excellent.
The number of ethylenic unsaturated groups that the unsaturated polyester resin has in one molecule is preferably 1 to 5, more preferably 1.5 to 5.0, and still more preferably 1.5 to 3.0.

The average number of hydroxyl groups which is the average of the number of hydroxyl groups that unsaturated polyester resin has in one molecule is 1.8 or more. When the average number of hydroxyl groups is 1.8 or more, the tackiness and the drapability of the obtained intermediate material become good.
The average number of hydroxyl groups is 4 or less, preferably 3.5 or less, and more preferably 3.3 or less. When the average number of hydroxyl groups is 4 or less, the thickening reaction between the components (A-1) and (A-3) preferentially occurs in the two-dimensional direction, and the reaction in the three-dimensional direction is suppressed. As a result, the handleability and fluidity of the obtained intermediate material are excellent.
The average number of hydroxyl groups in one molecule of the unsaturated polyester resin is preferably 1.8 to 3.5, and more preferably 1.8 to 3.3.

In the matrix resin of the present invention, the number of the ethylenically unsaturated groups which the component (A-1) has in one molecule is 1.0 or more, preferably 1.5 or more. In addition, the number of the ethylenically unsaturated groups is preferably 5.0 or less, more preferably 3.0 or less, and still more preferably 2.5 or less. When the number of the ethylenically unsaturated groups is in the above range, the curability, solvent resistance, heat resistance, mechanical properties and the like of the molded article of the present invention described later are further excellent.
The number of the ethylenically unsaturated group which the component (A-1) has in one molecule is preferably 1 to 5, more preferably 1.0 to 3.0, and still more preferably 1.0 to 2.5. 5 to 2.5 is particularly preferred.

In the matrix resin of the present invention, the average number of hydroxyl groups, which is the average of the number of hydroxyl groups possessed by the component (A-1) in one molecule, is 1.8 or more, preferably 2 or more. When the average number of hydroxyl groups is 1.8 or more, the tackiness and the drapability of the obtained intermediate material become good.
The average number of hydroxyl groups is 4 or less, preferably 3.8 or less.
Further, when the average number of hydroxyl groups is 4 or less, the thickening reaction between the component (A-1) and the component (A-3) preferentially occurs in the two-dimensional direction, and the reaction in the three-dimensional direction is suppressed. As a result, the handleability and fluidity of the obtained intermediate material are excellent.
The average of the number of hydroxyl groups that component (A-1) has in one molecule is preferably 1.8 to 3.8, and more preferably 2 to 3.8.

The matrix resin of the present invention contains both an epoxy (meth) acrylate resin and an unsaturated polyester resin as the component (A-1). That is, the component (A-1) is a mixture of an epoxy (meth) acrylate resin and an unsaturated polyester resin. By using the epoxy (meth) acrylate resin and the unsaturated polyester resin in combination, a rapid increase in the viscosity increase rate (initial thickening rate) after the component (A-3) is blended is suppressed. As a result, the product unevenness at the time of manufacturing the intermediate material is reduced, and the quality of the resulting molded article is also improved. In addition, solvent resistance is also improved by using an epoxy (meth) acrylate resin and an unsaturated polyester resin in combination.
The mass ratio of the epoxy (meth) acrylate resin to the unsaturated polyester resin (epoxy (meth) acrylate resin / unsaturated polyester resin) is preferably 1/4 to 4/1, and 1/2 to 2/1. More preferable. When the mass ratio is in the range, the above-mentioned effects tend to be exhibited.
In addition, in general, the epoxy (meth) acrylate resin can have a secondary hydroxyl group in the molecular terminal or in the molecule, and the unsaturated polyester resin can have a primary to tertiary hydroxyl group. Therefore, by using an unsaturated polyester resin having a primary hydroxyl group at the molecular terminal in combination with an epoxy (meth) acrylate, the hydroxyl group at the molecular terminal is preferentially reacted at the time of the thickening reaction with the component (A-3). There is a method. The matrix resin and the intermediate material obtained by this method tend to have a wider process window.

The content of the component (A-1) is preferably 60 to 75% by mass with respect to a total of 100% by mass of the thermosetting resin. If the content of the component (A-1) is 60% by mass or more, the component (A-2) remaining in the molded product tends not to be excessively large, and the VOC tends to be reduced. Note that “VOC” means an organic compound (volatile organic compound) that volatilizes under normal temperature or normal pressure or 60 to 80 ° C. environment.
When the content of the component (A-1) is 60% by mass or more, the process window at the time of producing the intermediate material becomes wider. Further, when the content of the component (A-1) is 75% by mass or less, the viscosity of the matrix resin does not become excessively high, and product spots and impregnation defects are not easily generated at the time of manufacturing the intermediate material. It becomes easy to get.

[(A-2) component]
The matrix resin of the present invention contains the component (A-2). The component (A-2) is also referred to as a polymerizable diluent.
As specific examples of the component (A-2), the following compounds may be mentioned. However, the component (A-2) is not limited to the following examples.

Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n- Nonyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, isobornyl ( Meta) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxyethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate ) Acrylate, tetrahydrofurfuryl (meth) acrylate, butanediol di (meth) acrylates, ethylene glycol di (meth) acrylates, hexanediol di (meth) acrylates, trimethylolpropane tri (meth) acrylate etc ) Acrylates.

Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and the like.
Adducts of 2-hydroxyethyl (meth) acrylate and ethylene oxide, adducts of 2-hydroxyethyl (meth) acrylate and propylene oxide, adducts of 2-hydroxyethyl (meth) acrylate and organic lactones (such as ε-caprolactone) And hydroxyl group-containing vinyl monomers.

Styrene-based monomers such as styrene and styrene derivatives (α-methylstyrene, pt-butylstyrene, vinyl toluene and the like).
(Meth) acrylamide compounds such as N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide and the like. Unsaturated carboxylic acids such as (meth) acrylic acid, itaconic acid, maleic acid and fumaric acid.
Polymerizable unsaturated nitriles such as (meth) acrylonitrile.
Unsaturated carboxylic acid esters such as diethyl maleate, dibutyl maleate, dibutyl fumarate, diethyl itaconate, dibutyl itaconate and the like.
Vinyl esters such as vinyl acetate and vinyl propionate.

One of these ethylenically unsaturated monomers may be used alone, or two or more thereof may be used in combination. When using in combination of 2 or more types, it may select suitably in consideration of the reactivity at the time of polymerization. For example, when importance is given to odor reduction when used as an intermediate material, an appropriate monomer may be selected depending on the use environment and the like. For example, in order to reduce odor, a component having a boiling point of 180 ° C. or higher at normal pressure may be selected. On the other hand, when importance is placed on economics, styrene-based monomers may be used. The boiling point at normal pressure may be measured, or a value converted based on literature such as Science of Petroleum, Vol. II, p. 1281 (1938) may be referred to.
Moreover, as a monomer of the property close | similar to a styrene-type monomer, vinyltoluene and butanediol di (meth) acrylate can be used suitably. Among these, styrene is preferred from the viewpoint of economy and polymerizability. If it is economically acceptable, the combined use of styrene and (meth) acrylates is preferred from the viewpoint of suppressing the change with time of the intermediate material.

The content of the component (A-2) is not particularly limited. In the matrix resin of the present invention, for example, the component (A-2) is preferably 10 to 40% by mass with respect to a total of 100% by mass of the thermosetting resin.
When the content of the component (A-2) is 10% by mass or more, the amount of the component (A-2) in the thermosetting resin becomes sufficient, and the neat resin viscosity can be lowered. As a result, the carbon fiber can be easily impregnated during production of the intermediate material, and the quality is further improved. In addition, there is a tendency that the VOC remaining in the molded article can be reduced.
If the content of the component (A-2) is 40% by mass or less, the amount of the component (A-2) in the thermosetting resin does not become excessive, and the VOC of the molded article can be suppressed to a low level. is there. In addition, since the compounding amount of the component (A-1) is not excessively reduced, the mechanical properties and Tg of the molded article can be within the suitable range.

[(A-3) component]
The matrix resin of the present invention contains the component (A-3).
The lower limit value of the isocyanate group content of the polyisocyanate is 15% by mass, preferably 25% by mass. When the isocyanate group content is 15% by mass or more, it is not necessary to blend the polyisocyanate excessively when manufacturing the intermediate material, and the decrease in heat resistance of the resulting molded article is reduced. Specifically, a decrease in Tg of a molded article obtained by DMA measurement described later is suppressed, and good heat resistance is maintained.

The upper limit value of the isocyanate group content of the polyisocyanate is 30.5% by mass, preferably 30.2% by mass. When the blending ratio of the component (A-1) to the component (A-3) deviates from the optimum value due to an external factor during production of the intermediate material because the isocyanate group content is 30.5 mass% or less However, the influence of the deviation can be reduced. Therefore, the process window becomes wider.
On the other hand, polyisocyanate having an isocyanate group content of more than 30.5% by mass is the content of at least one of 4,4'-diphenylmethane diisocyanate (hereinafter also referred to as "4,4 'MDI") and its modified product Often contain a large amount of 2,4'-diphenylmethane diisocyanate (hereinafter, also referred to as "2,4 'MDI"), which is an isomer of 4,4' MDI, etc., and modified products thereof. In addition, polyisocyanate having an isocyanate group content of more than 30.5% by mass may contain a large amount of mixed modified products such as 4,4'MDI and its isomer 2,4'MDI, and others 4,4 In many cases, they are produced by including a large amount of multifunctional modified products consisting of MDI and its isomers. As a result, the ripening period after the production of the intermediate material becomes excessively long, and the process window of the intermediate material becomes narrow. Therefore, polyisocyanate having an isocyanate group content of more than 30.5% by mass is not preferable from the viewpoint of productivity.
The isocyanate group content of the polyisocyanate is preferably 15 to 30.2% by mass, more preferably 25 to 30.5% by mass, and still more preferably 25 to 30.2% by mass.

The lower limit value of the average number of isocyanate groups of the polyisocyanate is 1.8, preferably 2.0. When the average number of isocyanate groups is 1.8 or more, the components (A-1) and (A-3) can be reliably connected at the time of thickening, and the intermediate material containing the matrix resin of the present invention is excellent in tackiness Have sex and drapability.
The upper limit of the average number of isocyanate groups in the polyisocyanate is 2.4. Thus, while the thickening reaction of the components (A-1) and (A-3) can proceed preferentially in the two-dimensional direction, the thickening reaction in the three-dimensional direction can be suppressed. The material has excellent fluidity.
The average number of isocyanate groups in the polyisocyanate is preferably 2.0 to 2.4.

The polyisocyanate can be appropriately selected from conventionally known polyisocyanate compounds used as a thickener, isocyanate prepolymers, and isocyanate modified products.
In the matrix resin of the present invention, particularly when liquid polyisocyanate is used as the component (A-3), the handleability and dispersibility tend to be excellent when producing the intermediate material. In this case, the contact between the polyisocyanate having a high concentration and the component (A-1) can be prevented until the liquid polyisocyanate is completely dissolved, as compared with the case where a solid polyisocyanate is used. It is possible to more effectively suppress the formation of polyfunctionals. As a result, it is possible to prevent the decrease in the formability of the intermediate material. In the present invention, liquid polyisocyanate and solid polyisocyanate may be mixed, and solid polyisocyanate may be finally liquefied and used as liquid polyisocyanate.

Examples of polyisocyanate compounds include 2,4-toluene diisocyanate (2,4TDI), 2,6-toluene diisocyanate (2,6TDI), 4,4'-diphenylmethane diisocyanate (4,4'MDI), isophorone diisocyanate (IPDI) And difunctional diisocyanates such as hexamethylene diisocyanate (HDI), xylene diisocyanate (XDI), and tetramethyl xylylene diisocyanate; and other trifunctional or higher polyisocyanate compounds.
As an isocyanate prepolymer, the compound obtained by reaction of the polyether polyol or polyester polyol which has a hydroxyl group, and diisocyanate is illustrated.
As the isocyanate-modified product, for example, carbodiimide-modified liquid MDI (MDI, MDI carbodiimide, MDI carbodiimide adduct as a main component) may be used.
One of these polyisocyanates may be used alone, or two or more thereof may be used in combination. In addition, when using solid polyisocyanate, it can be set as liquid polyisocyanate combining with liquid polyisocyanate.

In the matrix resin of the present invention, the liquid polyisocyanate preferably has one or more aromatic rings in the molecule. This makes it easy to maintain high mechanical properties of the molded article of the present invention described later. Examples of liquid polyisocyanates having one or more aromatic rings in the molecule include 4,4 'MDI, TDI and XDI. Among these, 4,4′MDI having an aromatic ring is more preferable from the viewpoint that the ripening period after the production of the intermediate material is not excessively long and the economic point.
From the above, component (A-3) is excellent in the handleability and dispersibility at the time of manufacturing the intermediate material, can shorten the aging period after manufacturing the intermediate material, and can maintain high mechanical properties of the molded product; Most preferred are liquid polyisocyanates which contain L, 4 'MDI as a main component and are liquefied by mixing 4, 4' MDI modified products (eg, carbodiimide-modified MDI etc.).
Component (A-3) is an MDI isomer such as 2,4 ′ MDI, a modified product of MDI isomer (eg, a carbodiimide modified product), 4,4 ′ MDI, and the like as long as there is no problem in practical use. It may contain at least one selected from the group consisting of a modified product (for example, carbodiimide modified product) consisting of a mixture of MDI isomers, the MDI isomer and a polyisocyanate other than the modified product of the MDI isomer.

The content of the component (A-3) is preferably such that the ratio of the number of moles of isocyanate groups in the component (A-3) to the number of moles of hydroxyl groups in the component (A-1) is 0.1 to 10 . When the ratio is 0.1 or more, tackiness and drapeability which are suitably used as an intermediate material can be easily provided. In addition, it is known that in the reaction of a hydroxyl group and an isocyanate group, when an isocyanate group is present in excess, the isocyanate group reacts with the previously formed urethane bond to take a polyfunctional structure. If the multi-functional structure is generated excessively, the fluidity of the intermediate material may be deteriorated, so the ratio is preferably 10 or less.

Regarding the blending amount of the component (A-3) with respect to 100 parts by mass of the thermosetting resin, the matrix resin of the present invention preferably satisfies the following formulas (1) to (4).
5 ≦ V 1 _X ≦ 40 (1)
Y ≧ 0.5 (2)
5 ≦ V1 _{X + Y} ≦ 70 (3)
5 ≦ V1 _XY ≦ 70 (4)
Matrix resin in which V1 _X is a reference amount X (parts by mass) with respect to 100 parts by mass of a thermosetting resin consisting of a component having an ethylenically unsaturated group in the formula (1). Is left to stand at 23 ° C. for 168 hours, and the viscosity is [× 10 ⁶ mPa · s], and the reference amount X is 10 to 40 parts by mass.
In the formula (2), Y is a difference [mass part] to increase or decrease the blending amount of the component (A-3) with respect to the reference amount X in the formula (1).
In the formula (3), V1 _{X + Y} is a matrix resin in which the blending amount of the component (A-3) is increased relative to the reference amount X in the formula (1) by the amount of difference Y in the formula (2) [parts by mass] The resulting solution had a ripening viscosity [× 10 ⁶ mPa · s] when allowed to stand at 23 ° C. for 168 hours. For example, the blending amount of the component (A-3) of the matrix resin in which the blending amount of the component (A-3) is increased by 0.5 [mass part] relative to the reference amount X is X + 0.5 [mass Department].
In the formula (4), V1 _XY decreased the blending amount of the component (A-3) with respect to the reference amount X in the formula (1) by the difference amount Y [parts by mass] in the formula (2) It is the ripening viscosity [× 10 ⁶ mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 168 hours. For example, the blending amount of the component (A-3) of the matrix resin in which the blending amount of the component (A-3) is reduced by 0.5 [parts by mass] with respect to the reference amount X is X-0.5 [Parts by mass]
In the formulas (1) to (4), the blending amount of the component (A-3) is a blending amount with respect to 100 parts by mass of the thermosetting resin.

When the matrix resin of the present invention is allowed to stand at 23 ° C. for 168 hours, the reference amount X (parts by mass) can satisfy the aging viscosity of 5 to 40 [× 10 ⁶ mPa · s] (A-3) The compounding amount is 100 parts by mass of the thermosetting resin. In this case, at 23 ° C., the matrix resin obtained when the compounding amount of the component (A-3) is increased or decreased by 0.5 parts by mass or more from the reference amount X [parts by mass] as the difference amount Y [parts by mass] It is preferable that the ripening viscosities V1 _{X + Y} and V1 _XY both when left to stand for 168 hours satisfy 5 to 70 [× 10 ⁶ mPa · s].
As a numerical range of the reference amount X [parts by mass], for example, a numerical value between 10 and 40 can be applied.

When the aging viscosity when the matrix resin is allowed to stand at 23 ° C. for 168 hours does not satisfy 5 to 40 [× 10 ⁶ mPa · s], the blending amount of the component (A-3) blended to the matrix resin is blended When the amount increases or decreases, the handleability and flowability of the obtained intermediate material tend to be impaired.
When the matrix resin is allowed to stand for 168 hours at 23 ° C., there is a matrix resin whose aging viscosity satisfies 5 to 40 [× 10 ⁶ mPa · s], and the blending of the component (A-3) blended in the matrix resin If the aging viscosity of the matrix resin obtained by increasing or decreasing 0.5 parts by mass or 0.5 parts by mass or more from the amount does not satisfy 5 to 70 [× 10 ⁶ mPa · s] Affected and prone to spotting, spotting that impairs handling and flowability.
As a specific example, when the difference amount Y [parts by mass] to the reference amount X [parts by mass] is 0.5 parts by mass, the level of the component (A-3) obtained is X [parts by mass], X + 0.5 Parts by mass] and X-0.5 [parts by mass]. In addition, when Y [parts by mass] is 0.3 parts by mass, the level of the component (A-3) obtained is X [parts by mass], X + 0.3 [parts by mass], X-0.3 [mass] When the Y (parts by mass) is 1.0 parts by mass, the level of the component (A-3) obtained is X (parts by mass), X + 1.0 (parts by mass), X-1 .0 Three parts of [mass parts]. However, the level of the component (A-3) is not limited to three. For example, when Y [parts by mass] is 1.0 part by mass or 0.5 parts by mass, the level of the component (A-3) obtained is X [parts by mass], X + 1.0 [parts by mass], X- It becomes five levels of 1.0 [parts by mass], X + 0.5 [parts by mass], and X-0.5 [parts by mass].

If the difference amount Y [parts by mass] is less than 0.5, when the compounding amount of the component (A-3) is increased or decreased depending on the accuracy of equipment or equipment used at the time of manufacturing the intermediate material, manufacturing unevenness occurs in the intermediate material There is a risk of becoming easier. Therefore, the difference amount Y [parts by mass] is preferably 0.5 or more. The upper limit value of the difference amount Y [parts by mass] is preferably 5.0 or less, more preferably 3.0 or less, and still more preferably 2.0 or less.
The difference amount Y [parts by mass] is preferably 0.5 to 5.0, more preferably 0.5 to 3.0, and still more preferably 0.5 to 2.0.

[(A-4) component]
The matrix resin of the present invention contains a thermal polymerization initiator as the component (A-4). The thermal polymerization initiator is a compound which generates a radical species by heating. The component (A-4) is not particularly limited. Examples of the component (A-4) include peroxydicarbonates, peroxyesters, peroxymonocarbonates, peroxyketals, and organic peroxides such as dialkyl peroxides.

Specific examples of the component (A-4) include t-amylperoxypropyl carbonate (product name: AIC 75, manufactured by Kayaku Akzo Co., Ltd.), t-butylperoxy isopropyl carbonate (product name: BIC-75, chemicals) Manufactured by Akzo Co., Ltd., 1,1-di (t-hexylperoxy) cyclohexane (product name: perhexa HC), 1,1-di (t-butylperoxy) cyclohexane (product name: perhexa C-80 (S) or Examples are organic peroxides such as perhexa C-75 (EB) and the like, methyl ethyl ketone peroxide, t-butyl peroxybenzoate, benzoyl peroxide, dicumyl peroxide, cumene hydroperoxide and the like. Among these, as the component (A-4), when it is desired to reduce the residual amount of the ethylenic functional group, it is preferable to use t-amyl peroxypropyl carbonate having an amyl group in the molecule. Further, from the viewpoint of the stability to various auxiliary agents and the stability with time, a compound having a small number of acyl groups in the molecule is preferable. The smaller the number of acyl groups in the molecule, the better the stability.

The component (A-4) can be appropriately changed depending on the temperature at which the polymerization is initiated, the curing time required, etc., and one type may be used alone, or two or more types may be used in combination. Also, it is useful to intentionally combine initiators having different 10-hour half-life temperatures in order to shorten the curing time during polymerization.

The content of the component (A-4) is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more based on 100% by mass of the thermosetting resin. When the content of the component (A-4) is 0.1% by mass or more, the content of the residual monomer contained in the molded product can be further reduced, and as a result, the VOC generated from the molded product can be further reduced. Can.
The content of the component (A-4) is preferably 5.0% by mass or less, and more preferably 3.0% by mass or less, based on 100% by mass of the thermosetting resin. When the content of the component (A-4) is 5.0% by mass or less, the molecular weight of the cured product of the thermosetting resin contained in the molded product does not become excessively small, and the mechanical properties of the molded product and the Tg decrease. Will be easier to prevent.
The content of the component (A-4) is preferably 0.1 to 5.0% by mass, more preferably 0.1 to 3.0% by mass, with respect to 100% by mass of the thermosetting resin. 5.0 mass% is more preferable, and 0.5 to 3.0 mass% is more preferable.

[(A-5) component]
The matrix resin of the present invention may contain the component (A-5).
Examples of the component (A-5) include urethane (meth) acrylate oligomers, epoxy (meth) acrylate oligomers, polyester (meth) acrylate oligomers, (meth) acrylate half esters and the like.
As a commercial item of (A-5) component, urethane (meth) acrylate series (made by SARTOMER), such as CN9023 and CN9028, is illustrated. In addition, examples of the products previously mixed with styrene include CBZ500 series, CBZ255 series, CBZ650F series, CBZFX, and R (manufactured by Japan Yupica Co., Ltd.). However, the component (A-5) is not limited to these.
When the matrix resin of the present invention contains the component (A-5), an example of the content of the component (A-5) can be 0 to 30% by mass with respect to 100% by mass of the thermosetting resin. . In the present invention, depending on the viscosity of the matrix resin after compounding, the ratio of the compounding amount of the component (A-5) to the component (A-2) can be selected.

[Other ingredients]
The matrix resin of the present invention may contain other components. Other components include curing accelerators, inorganic fillers, internal mold release agents, stabilizers (polymerization inhibitors), pigments, colorants, wetting and dispersing agents, water absorbing agents, ultraviolet light absorbers, light stabilizers, and antioxidants. Etc. are illustrated.
Specific examples of the curing accelerator include metal soaps represented by cobalt naphthenate, cobalt octenate, zinc octylate, vanadyl octenate, copper naphthenate, barium naphthenate, etc., vanadyl acetyl acetate, cobalt acetyl acetate, iron Metal complexes represented by acetylacetonate etc., aniline, N, N-dimethylamino-p-benzaldehyde, N, N-dimethylaniline, N, N-diethylaniline, N, N-dimethyl-p-toluidine, N Examples are amines represented by -ethyl-m-toluidine, triethanolamine, m-toluidine, diethylenetriamine, pyridine, phenylmorpholine, piperidine, diethanolaniline and the like. However, the curing accelerator is not limited to these.
Among these, as a curing accelerator, a curing accelerator of amines is particularly preferable. These curing accelerators may be used alone or in combination of two or more.
When the matrix resin contains a curing accelerator, the content of the curing accelerator is preferably 0.001 to 5 parts by mass with respect to 100 parts by mass of the thermosetting resin.

Specific examples of the inorganic filler include carbon fiber powder, carbon fiber milled, fiber milled, calcium carbonate, magnesium carbonate, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, silica, fused silica, barium sulfate, titanium oxide, oxide Examples include magnesium, calcium oxide, aluminum oxide, calcium phosphate, talc, mica, clay, glass powder and the like. However, the inorganic filler is not limited to these.
One of these inorganic fillers may be used alone, or two or more thereof may be used in combination. Among these, carbon fiber powder and carbon fiber milled which have a small density and a high reinforcing effect are preferably used.
When the matrix resin contains an inorganic filler, the content of the inorganic filler is preferably minimized from the viewpoint of weight reduction. For example, the content of the inorganic filler is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the thermosetting resin.

Specific examples of the internal mold release agent include fatty acid metal salts such as calcium stearate and zinc stearate; surfactants such as sodium dialkyl sulfosuccinate and the like. However, the internal mold release agent is not limited to these.
One of these internal release agents may be used alone, or two or more of them may be used in combination.
When the matrix resin contains an internal mold release agent, the content of the internal mold release agent can be appropriately set according to the level of releasability to be obtained and the additive material. The content of the internal mold release agent is preferably, for example, 0.1 to 10 parts by mass with respect to 100 parts by mass of the thermosetting resin.

As a suitable specific example of a ultraviolet absorber, various additives represented by benzotriazole type and triazine type are used suitably. As a commercial item of the suitable example of a ultraviolet absorber, Tinuvin PS, Tinuvin 479, Tinuvin 571 (product name, all are BASF Corporation make) are illustrated. However, the ultraviolet absorber is not limited to these. These ultraviolet absorbers may be used alone or in combination of two or more.

It is known that the conventionally known component (A-1) generally has a wide light absorption band in the ultraviolet region and the visible light region, and absorbs a part of visible light. Therefore, when selecting a UV absorber, it is preferable that the UV absorber has a high absorbance and a wide absorption band, and a material whose absorption band extends to the visible light region is more preferable.
When the matrix resin contains an ultraviolet absorber, the content of the ultraviolet absorber is preferably 1 to 10 parts by mass with respect to 100 parts by mass of the thermosetting resin.

The light stabilizer is not particularly limited. As the light stabilizer, for example, various additives typified by hindered phenols are suitably used. For example, Tinuvin 123, Tinuvin 5100, Tinuvin 765 (product name, all manufactured by BASF Corporation) are exemplified. However, the light stabilizer is not limited to these. One of these light stabilizers may be used alone, or two or more thereof may be used in combination.
When the matrix resin contains a light stabilizer, the content of the light stabilizer is preferably 1 to 5 parts by mass with respect to 100 parts by mass of the thermosetting resin. The light stabilizer may be blended in a range not to inhibit the polymerization.
In addition, those effects will become higher by using together a ultraviolet absorber and an optical stabilizer rather than using each independently.

As a specific example of an antioxidant, various additives represented by a hindered phenol type are suitably used. Examples of commercially available antioxidants include Irganox 1010, Irganox 1726, Irganox 1035, Irganox 1076, and Irganox 1135 (product names, all manufactured by BASF Corporation). However, the antioxidant is not limited to these. One of these antioxidants may be used alone, or two or more thereof may be used in combination.
When the matrix resin contains an antioxidant, the content of the antioxidant is preferably 1 to 10 parts by mass with respect to 100 parts by mass of the thermosetting resin. Antioxidants, which have high radical sensitivity, may inhibit polymerization and curing more than light stabilizers. Therefore, it is preferable to limit the content to an optimum.

The ripening viscosity of the thickened material of the matrix resin of the present invention at 23 ° C. is preferably 5 [× 10 ⁶ mPa · s] or more, and more preferably 6 [× 10 ⁶ mPa · s] or more. Also, the ripening viscosity is preferably 70 [× 10 ⁶ mPa · s] or less, and more preferably 60 [× 10 ⁶ mPa · s] or less.
The aging viscosity at 23 ° C. of the thickened substance of the matrix resin is preferably 5 to 70 [× 10 ⁶ mPa · s], more preferably 6 to 70 [× 10 ⁶ mPa · s], and 5 to 60 [× 10 ⁶ mPa · s]. The viscosity is more preferably mPa · s], and particularly preferably 6 to 60 [× 10 ⁶ mPa · s].

It is preferable that the matrix resin of this invention satisfy | fills the following Formula (5) and the following Formula (6).
5 ≦ V1 ≦ 40 (5)
V2 / V1 ≦ 2.5 (6)
In Formula (5), V1 is the aging viscosity [× 10 ⁶ mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 168 hours.
In the formula (6), V1 is the same as V1 in the formula (5), and V2 is a ripening viscosity [× 10 ⁶ mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 336 hours.

When the matrix resin of the present invention satisfies the formula (5), the handleability and fluidity of the obtained intermediate material tend to be excellent, and product spots are less likely to occur.
When the matrix resin of the present invention satisfies the above-mentioned formula (6), the storage stability of the obtained intermediate material is excellent, the time change of the handleability and fluidity of the intermediate material is small, and the excellent characteristics can be maintained over a long period of time. is there.
From the above, when the matrix resin of the present invention satisfies the above (5) and the above (6), the handleability and the flowability of the obtained intermediate material are further improved, and product spots are less likely to occur, and storage stability of the intermediate material Further, it is possible to maintain excellent properties such as handleability and fluidity of the intermediate material for a long time.

In the matrix resin of the present invention, the neat resin viscosity Vn of the thermosetting resin is preferably 1000 [mPa · s] or less, and more preferably 800 [mPa · s] or less. When the neat resin viscosity Vn is 1000 [mPa · s] or less, it is difficult for the carbon fiber bundle to be poorly impregnated during the production of the intermediate material, and it becomes easy to obtain the intermediate material with few product spots.
The neat resin viscosity Vn of the thermosetting resin is preferably 100 [mPa · s] or more, and more preferably 150 [mPa · s] or more. When the neat resin viscosity Vn is not less than 100 [mPa · s], it is not necessary to excessively add the component (A-2), and separation of a thickened product of a thermosetting resin and a carbon fiber bundle at the time of intermediate material production Is less likely to occur. In addition, it is not necessary to extremely reduce the molecular weight of the component (A-1), and the tackiness of the intermediate material does not become excessively strong, which tends to make it possible to obtain an intermediate material having excellent handleability.
The neat resin viscosity Vn of the thermosetting resin is preferably 100 to 1000 [mPa · s], more preferably 150 to 1000 [mPa · s], still more preferably 100 to 800 [mPa · s], and 150 to 800 [mPa · s]. Particularly preferred is mPa · s].

In the matrix resin of the present invention, it is preferable to set an appropriate neat resin viscosity according to the carbon fiber content required for an intermediate material described later. Specifically, for example, in the case of producing an intermediate material having a carbon fiber content of 60% by mass or more, a lower neat resin viscosity tends not to cause impregnation failure or the like.

It is preferable that the matrix resin of this invention satisfy | fills the following Formula (7) and the following Formula (8).
0.6 ≦ a1 / b ≦ 0.75 (7)
Vn ≦ 1000 (8)
In the formula (7), a1 is the content [g] of the component (A-1), and b is the content [g] of the thermosetting resin composed of the component having an ethylenically unsaturated group.
In Formula (8), Vn is a neat resin viscosity [mPa · s] of a thermosetting resin comprising a component having an ethylenically unsaturated group.

When the matrix resin of the present invention satisfies the formulas (7) and (8), VOCs are easily reduced, and it is further difficult to cause poor impregnation of the carbon fiber bundle at the time of manufacturing the intermediate material, and there are few product spots. It becomes easier to obtain the intermediate material.

The matrix resin of the present invention is, for example, component (A-1), component (A-2), component (A-3) and component (A-4) and, if necessary, component (A-5) and other components Can be produced by mixing
The method for producing the matrix resin of the present invention is not particularly limited as long as each component can be dispersed or dissolved uniformly. For example, a component (A-1), a component (A-2) and a component (A-3) are mixed, and a pre-matrix resin in which the component (A-4) is removed from the matrix resin is manufactured in advance, There is a method of mixing the resin and the component (A-4). This method is preferably used because it is easy to control and it is difficult to cause product spots during intermediate material production.
In addition, when manufacturing pre-matrix resin or matrix resin, mixers, such as a three-roll mill, a planetary mixer, a kneader, a universal stirrer, a homogenizer, a homo dispenser, etc., can be used. However, the mixer is not limited to these.

The matrix resin of the present invention preferably satisfies the following formula (9).
V10 / Vs ≦ 1.20 (9)
In formula (9), Vs is the viscosity [mPa · s] immediately after mixing the pre-matrix resin obtained by removing the component (A-3) from the matrix resin and the component (A-3), and V10 is the above-mentioned It is a viscosity [mPa · s] when 10 minutes have elapsed by mixing the pre-matrix resin and the component (A-3).

In said Formula (9), V10 / Vs means the initial stage viscosity rate of matrix resin. The initial viscosity ratio (V10 / Vs) is preferably 1.2 or less, more preferably 1.14 or less, and still more preferably 1.10 or less. When the initial viscosity ratio (V10 / Vs) is 1.2 or less, product unevenness is less likely to occur during the production of the intermediate material, and it becomes easy to produce a good intermediate material.
If the initial thickening rate (V10 / Vs) is more than 1.2, product unevenness is likely to occur during production of the intermediate material, and impregnation defects may occur in some places, and the basis weight of the intermediate material described later tends to differ from place to place There is.
The lower limit of the initial viscosity ratio (V10 / Vs) is theoretically 1.0. The initial viscosity ratio (V10 / Vs) is preferably 1.0 to 1.2, more preferably 1.0 to 1.14, and still more preferably 1.0 to 1.10.

(Action effect)
Since the matrix resin of the present invention described above has an isocyanate group content of 30.5 mass% or less of the liquid polyisocyanate of the component (A-3), the component (A-1) and the component 3) Even if the blending ratio with the component deviates from the optimum value due to an external factor, the influence of the blending ratio deviation becomes small and the process window becomes wider.

<Intermediate material>
The intermediate material of the present invention comprises the matrix resin of the present invention and a carbon fiber bundle having a fiber length of 5 to 120 mm.

[Carbon fiber bundle]
The carbon fiber bundle is obtained, for example, by cutting a carbon fiber bundle made of continuous carbon fibers.
Examples of carbon fibers constituting the carbon fiber bundle include polyacrylonitrile (PAN) carbon fibers, rayon carbon fibers, pitch carbon fibers, and the like. Among them, PAN-based carbon fibers are preferable in terms of excellent compressive strength and low density. These carbon fibers may be used alone or in combination of two or more.

The fiber length of the carbon fiber bundle is 5 mm or more, preferably 10 mm or more. When the fiber length of the carbon fiber bundle is 5 mm or more, the mechanical properties of the intermediate material show sufficient characteristics, and a molded article applicable to applications requiring high strength and high elasticity can be obtained.
The fiber length of the carbon fiber bundle is 120 mm or less, preferably 80 mm or less. When the fiber length of the carbon fiber bundle is 120 mm or less, excellent fluidity can be exhibited at the time of molding, and variations in mechanical properties and the like in the molded product can be suppressed.
In the intermediate material of the present invention, since the fiber length of the carbon fiber bundle is 5 to 120 mm, it is possible to achieve both mechanical properties of the molded product, suppression of variations in mechanical properties, and flowability at the time of molding.
The fiber length of the carbon fiber bundle is preferably 10 to 120 mm, more preferably 5 to 80 mm, and still more preferably 10 to 80 mm.

1000 or more are preferable and, as for the filament number of a carbon fiber bundle, 2000 or more are more preferable. If the number of filaments of the carbon fiber bundle is 1,000 or more, entanglement of the carbon fiber bundles in the intermediate material can be easily suppressed, and excellent fluidity can be easily exhibited at the time of molding. Further, the number of filaments of the carbon fiber bundle is preferably 80000 or less, more preferably 60000 or less. When the number of filaments of the carbon fiber bundle is 80,000 or less, since the size of each bundle is sufficiently small, it is easy to reduce the variation in mechanical properties in the molded product.
The number of filaments of the carbon fiber bundle is preferably 1000 to 80,000, more preferably 1000 to 60000, and still more preferably 2000 to 60000.
As a carbon fiber bundle, the number of filaments may use the thing of the said range. Carbon fiber bundles having a number of filaments, for example, in the range of 30,000 to 100,000 may be used after being divided in-line or off-line to make the number of filaments within the above range.

30 mass% or more is preferable, and, as for the ratio of the carbon fiber bundle in the intermediate material of this invention, ie, carbon fiber content, 35 mass% or more is more preferable. Moreover, 75 mass% or less is preferable, and, as for the carbon fiber content rate, 70 mass% or less is more preferable. When the carbon fiber content is 30% by mass or more, a molded article having sufficient mechanical properties and applicable to applications requiring high strength and high elasticity is easily obtained. When the carbon fiber content is 70% by mass or less of the above range, it becomes easy to impregnate the carbon fiber bundle with the matrix resin, and when forming the intermediate material, it is easy to express good fluidity, and forming It tends to be easy to control the appearance defect of the product.
The carbon fiber content is preferably 30 to 75% by mass, more preferably 35 to 75% by mass, still more preferably 30 to 70% by mass, and particularly preferably 35 to 70% by mass.

The lower limit of the basis weight of the carbon fiber bundle is preferably 50 g / ^{m 2,} more preferably ^{^{500g / m 2, 800g / m}} 2 is more preferred. The upper limit of the basis weight of the carbon fiber bundle is preferably ^{^{4000g / m 2, 3000g / m}} 2 is more preferable. When the weight per unit area of the carbon fiber bundle is within the above upper limit value and the above lower limit value, carbon fibers in the intermediate material tend to be uniform, mechanical properties of the molded article of the present invention described later tend to be good, It becomes easy to reduce the variation. In particular, it is preferable that the intermediate material contains a carbon fiber bundle having a weight per unit area of 1000 g / m ² or more, because the elastic modulus of the resulting molded product is further increased.
Basis weight of the carbon fiber bundle is preferably 50 ~ 4000g / ^{m 2,} more preferably 500 ~ 4000g / ^{m 2,} more preferably 800 ~ 4000g / ^{m 2,} particularly preferably 800 ~ 3000g / ^{m 2.}

The intermediate material of the present invention may contain a carbon fiber bundle having a fiber length of less than 5 mm and a carbon fiber bundle having a fiber length of more than 120 mm, as long as the effects of the present invention are not impaired. In addition, the intermediate material of the present invention may include a fiber bundle composed of fibers other than carbon fibers, as long as the effects of the present invention are not impaired.
Examples of fibers other than carbon fibers include glass fiber bundles and organic fiber bundles. For example, when the intermediate material of the present invention contains glass fiber bundles as fibers other than carbon fibers, the impregnation of the matrix resin at the time of manufacturing the intermediate material tends to be improved. In addition, when the intermediate material of the present invention includes an organic fiber bundle that can be dissolved in a matrix resin, restraint of carbon fiber bundles can be relaxed, and the fluidity of the intermediate material can be improved.

When the intermediate material of the present invention contains fibers other than carbon fiber bundles, the ratio of the carbon fiber bundles is preferably 90% by mass or more, more preferably 95% by mass or more based on 100% by mass of the fibers contained in the intermediate material. . In addition, the upper limit of the ratio of a carbon fiber bundle is 100 mass%.

The method for producing an intermediate material according to the present invention at least includes the following first to third steps.
First step: a step of producing a matrix resin.
Second step: Carbon fiber bundles having a fiber length of 5 to 120 mm are randomly deposited in two dimensions to form a sheet, and the sheet is impregnated with a matrix resin to obtain an intermediate material precursor.
Third step: a step of thickening or aging the matrix resin contained in the intermediate material precursor.
In the third step, the hydroxyl group contained in the component (A-1) derived from the matrix resin and the isocyanate group contained in the component (A-4) derived from the matrix resin are reacted.

As the conditions for performing the third step, although depending on the components contained in the matrix resin, conditions for thickening or aging usually at 10 to 80 ° C. for 0.5 to 30 days can be applied. The matrix resin is aged under the conditions and thickened to obtain a thickened product of the matrix resin.
When the third step is carried out, the aging viscosity V1 and the aging viscosity V2 are measured, and the aging viscosity V1 satisfies 5 to 40 [× 10 ⁶ mPa · s], and the thickening ratio (V2 / V1) is 2. It is preferable to confirm that it is 5 or less. As a result, it becomes easy to obtain an intermediate material which is excellent in storage stability, is less likely to change in handleability and fluidity over time, and can maintain excellent properties over a long period of time.

As a specific manufacturing method example of the intermediate material, first, a matrix resin is coated on a carrier film using a doctor blade or the like. The thickness of the matrix resin may be appropriately set in accordance with the application of the intermediate material to be produced. The thickness of the matrix resin can be, for example, 0.1 to 3 mm. Next, a sheet-like material formed by laminating carbon fiber bundles in a two-dimensional random manner by spraying carbon fiber bundles cut into a desired length on the surface of the matrix resin coated on the carrier film. Form Next, another carrier film provided with a matrix resin is laminated so that the matrix resin faces the sheet-like material to produce a laminated film. By pressurizing the laminated film, the sheet-like material made of carbon fiber bundles is impregnated with the matrix resin to produce an intermediate material precursor. The thickness of the sheet-like material after pressing is, for example, 0.5 to 5 mm. Finally, the intermediate material can be obtained by maturing the matrix resin contained in the obtained intermediate material precursor.

Since the intermediate material of the present invention described above contains the matrix resin of the present invention, the process window is wide. At the time of production of the intermediate material of the present invention, since the matrix resin contains liquid polyisocyanate, sudden thickening reaction hardly occurs as compared with the case of using powdery isocyanate-based thickener, and epoxy (meth) The three-dimensional thickening reaction between the acrylate and the liquid polyisocyanate is suppressed. Therefore, the intermediate material of the present invention has few product spots at the time of manufacture.

<Molded item>
The molded article of the present invention is a cured product obtained by curing the intermediate material of the present invention and heat and pressure molding.
For example, the following method can be applied as a method of curing the intermediate material of the present invention and performing heat and pressure molding.
The intermediate material of the present invention is placed between one or a plurality of sheets, placed between a pair of molds, and then the intermediate material placed is heated and pressed to cure the thickened product of the matrix resin contained in the intermediate material. How to

The temperature at the time of heat and pressure molding can be, for example, 80 to 180 ° C. It may be selected in consideration of the VOC level required for the molded product, the molding time at the time of manufacturing the molded product, and the like.
The time of the heating and pressurizing step is, for example, 0.5 to 60 minutes. It may be appropriately selected in consideration of the shape of the molded product, the flow thickness and the like.

In the molded article of the present invention, the temperature at which the loss tangent measured by dynamic viscoelasticity measurement at a frequency of 1 Hz shows a maximum value (hereinafter also referred to as "tan δmax") is preferably 120 ° C or more, 130 ° C or more is more preferable, and 140 ° C. or more is particularly preferable. The heat resistance of a molded article is further excellent as tandeltamax is 120 ° C or more, and it can be used conveniently irrespective of a use. In addition, even when the temperatures of the upper and lower molds at the time of molding are high and there is a temperature difference between the upper and lower molds, there is a tendency to be able to be suitably released, and the productivity is further excellent.

The molded article of the present invention comprises the intermediate material of the present invention and materials other than the intermediate material of the present invention, such as unidirectional materials, woven fabrics, non-woven fabrics, etc. composed of conventionally known thermosetting or thermoplastic prepregs or fibers. You may obtain by combining. In particular, a molded article obtained by molding the intermediate material of the present invention and a thermosetting or thermoplastic prepreg exhibits superior mechanical properties by the prepreg layer. In addition, the intermediate material can form convex portions such as ribs and bosses, and is excellent in the degree of freedom in forming shape.

In the case of molding the intermediate material of the present invention and a thermosetting or thermoplastic prepreg, the resin contained in the prepreg may be the same as or different from the matrix resin of the present invention. The resin contained in the prepreg is not particularly limited as long as the strength of the interface between the prepreg and the intermediate material can be maintained at a desired level. In addition, depending on the molding shape, when the curing time of the prepreg and the intermediate material of the present invention, for example, Cure Time, is made to be close to each other, appearance defects and reduction in interfacial adhesion of the resulting molded article tend to be reduced is there.

The molded article of the present invention comprises (1) a plurality of the intermediate materials of the present invention disposed on the surface layer, and a honeycomb structure such as cardboard as the core material between the intermediate materials; (3) It may be obtained by heat and pressure molding after filling the matrix resin containing no fiber between the above-mentioned intermediate materials. In this case, the molded article tends to exhibit excellent mechanical properties as well as the lightness is improved.

The molded article of the present invention described above is obtained by heat and pressure molding the above-described intermediate material of the present invention, so that an excessive amount of polyisocyanate is not present, and a decrease in Tg can be suppressed. Therefore, the molded article of the present invention is excellent in mechanical properties and heat resistance.

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the embodiments are also possible. It is included in the technical scope of the present invention.

EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited by the following description. In addition, "part" and "%" in an Example represent "mass part" and "mass%", respectively.

Raw materials used
[A mixture of the (A-1) component and the (A-2) component]
-CSVE (made by Nippon Yupika Co., Ltd., a mixture of epoxy (meth) acrylate resin and styrene, styrene content 33% by mass, average number of hydroxyl groups: 2.1)
・ DP 132 (made by Nippon Yupica Co., Ltd., a mixture of unsaturated polyester resin and styrene, styrene content 33 mass%, average number of hydroxyl groups 3.2)
-Neopol 8051 (manufactured by Japan Yupica Co., Ltd., a mixture of epoxy (meth) acrylate resin and styrene, styrene content 32% by mass, average number of hydroxyl groups 1.8 to 4.0)
[(A-3) component]
・ Cosmonate LL (Mitsui Chemical Co., Ltd., isocyanate group content 29.5% by mass, average isocyanate group number 2.1, main component 4, 4 'MDI)
-Lupranate MM103 (manufactured by BASF, 29.5% by mass of isocyanate group content, average number of isocyanate groups 2.2, main component 4, 4 'MDI)
-SUPRASEC 2020 (manufactured by HUNTSMAN, isocyanate content: 29.5% by mass, average number of isocyanate groups: 2.1, main component 4, 4 'MDI)
Desmodur CD-S (Covestro Co., Ltd., isocyanate content: 29.7% by mass, average number of isocyanate groups: 2.1, main component 4, 4 'MDI)
-Dion 31100 (made by Reichhold, isocyanate group content 22.7 mass%, average isocyanate group number 2.4 or less, main component 4, 4 'MDI)
-Mondur MR (manufactured by Covestro, 31.5% by mass of isocyanate group content, average number of isocyanate groups: 2.8, other than main component 4, 4 'MDI)
-SUPRASEC 2385 (manufactured by HUNTSMAN, isocyanate content 30.9% by mass, average number of isocyanate groups 2.0, main component 4, 4 'MDI)
-Lupranate MX121 / 1 (manufactured by BASF, having an isocyanate content of 33% by mass, an average number of isocyanate groups of 2.2, other than the main component 4, 4 'MDI)

<Measurement method>
(Neat resin viscosity Vn)
Neat resin viscosity Vn of thermosetting resin consisting of component having ethylenic unsaturated group, viscosity Vs of pre-matrix resin, viscosity V10 of matrix resin, TB-10 equipped with M3 rotor under 23 ° C. environment The measurement was performed using an industrial company). The rotor rotational speed was implemented at 60 rpm.

(Aging viscosity)
Aging viscosity V1 after leaving the matrix resin to stand in a 23 ° C environment for 168 hours, and a aging viscosity V2 after leaving the matrix resin to stand in a 23 ° C environment for 336 hours, helipath type digital equipped with T-Bar spindle TF It was carried out using a viscometer HB DV-1 prime (manufactured by BROOKFIELD).
The ripening viscosity was measured while descending from the surface to the lower surface of the matrix resin, and was 0 seconds when it was in contact with the surface of the matrix resin, and the instantaneous value at the time of 120 to 150 seconds was used. The spindle rotational speed was adjusted in the range of 0.3 to 50 rpm, and was adjusted so that the torque at the time of measurement was in the range of 10 to 70%, preferably in the range of 30 to 50%.

(Thickening ratio)
Based on the aging viscosity V1 and the aging viscosity V2 obtained by measuring the aging viscosity, the thickening ratio was calculated by the following equation (10). When the thickening ratio was 2.5 or less, it was judged that the stability after aging was excellent, and the storage stability when used as an intermediate material was excellent. In addition, calculation of the thickening ratio was performed about matrix resin whose ripening viscosity V1 is 3.0 [* 10 < ⁶ > mPa * s] or more.
(Thickening ratio) = V2 / V1 (10)

(Initial thickening rate)
The viscosity Vs of the matrix resin immediately after mixing and stirring the component (A-3) with the pre-matrix resin, and the viscosity Vs of the matrix resin after mixing and stirring, and the viscosity of the matrix resin when 10 minutes have passed immediately after mixing and stirring V10 was measured in the same manner as neat resin viscosity Vn. Based on Vs and V10 thus obtained, the initial thickening rate was calculated by the following equation (11).
(Initial thickening rate) = V10 / Vs (11)

(DMA measurement)
A test piece 55 mm long, 12.7 mm wide, and 2 mm thick is cut out from a molded plate, and the measurement frequency is increased by 1 Hz using (ARES-RDS, manufactured by TA Instruments Japan Co., Ltd.) Measurements are made at a temperature rate of 5 ° C./min in the region from 30 to 250 ° C., log G ′ and log G ′ ′ and loss tangent (tan δ) are plotted against temperature, dynamic viscoelasticity under the condition of frequency 1 Hz The temperature at which the loss tangent (tan δ) measured by the measurement shows a maximum value was taken as tan δ max. The larger the tan δmax, the better the heat resistance. In addition, when tan δmax was 120 ° C. or more, the heat resistance was good, and when tan δ max was 140 ° C. or more, it was judged that the heat resistance was excellent.

<Evaluation method>
(Handling)
Whether or not it adheres to gloves when 3 to 20 g of resin pieces are pulled out by an operator's hand from the inside excluding 1 cm thickness from the surface layer of matrix resin left to stand for 168 hours at 23 ° C. after compounding The handling was judged by. The evaluation criteria for handling are as follows.
"○": There is no adhesion to gloves, and good handling can be expected when used as an intermediate material.
"△": There is no adhesion to gloves, and when used as an intermediate material, it can be expected that handling is possible although the stiffness is weak.
"X": The cut-out of matrix resin is impossible, or adhesion to a glove is confirmed.

(Melting ability)
After compounding, 1 to 5 g of resin pieces were cut out from the inside of the surface layer of the matrix resin which was left to stand at 23 ° C. for 168 hours in an environment of 1 cm in thickness. The resin piece was allowed to stand on a heating plate at 140 ° C., and then the matrix resin was moved concentrically while pressing with a spatula to confirm dissolution behavior and to evaluate meltability. The criteria for evaluation of the meltability are as follows.
"(Circle)": Although uniform or undissolved component is scattered, it is possible to form a uniform resin coating film, and when it is set as an intermediate material, favorable moldability can be anticipated.
"(Triangle | delta)": Although the undissolved component adheres to a heating board, it does not lead to formation of a coating film. When it is used as an intermediate material, it is expected that the formability is inferior.
"X": does not adhere to the heating plate. When it is used as an intermediate material, the formability is expected to be extremely poor.

(Process window)
The process window was evaluated based on the evaluation results of handleability and meltability in a plurality of matrix resins in which the blending amount of the component (A-3) was increased or decreased by the difference amount Y from the reference amount X. As for the judgment of the process window, the result of the handling evaluation is “o” or “Δ”, and the result of the meltability evaluation is “o” satisfying the “o” component (A-3). At one time, it was determined that the process window was good. This means that product unevenness can be reduced at the time of intermediate material production.

(Impregnability of intermediate material)
The impregnatability of the intermediate material is evaluated by the operator visually confirming the surface area and the inside of the intermediate material precursor and the intermediate material after removing the carrier film from the manufactured intermediate material precursor and the intermediate material. did. The inspection was conducted in the entire width direction. The judgment index is as follows.
Evaluation Criteria "〇": The wetting of the matrix resin with the carbon fiber bundle was good, and the matrix resin was present substantially uniformly throughout.
"B": The wetting of the matrix resin to the carbon fiber bundle was partially insufficient, but the impregnation proceeded at the time of thickening, and the wetting of the matrix resin to the reinforcing fiber bundle after thickening was good.
"X": The wetting of the matrix resin to the carbon fiber bundle was insufficient, and the wetting of the matrix resin to the reinforcing fiber bundle was insufficient even after thickening.

(Bending test)
Twelve test pieces of 100 mm long, 25 mm wide and 2 mm thick from a molded plate of 300 mm x 300 mm, using a 5 kN Instron universal testing machine, L / D = 40, crosshead speed 5 mm / min 3 A point bending test was carried out to determine the average value of bending strength and flexural modulus. In any case, the higher the numerical value, the better the mechanical properties.

(Formability)
A plurality of intermediate materials which were allowed to stand for 168 hours in a 23 ° C. environment after production were cut out into 60 to 80 mm squares to obtain a laminate. The number of stacked layers was adjusted so that the weight of the stack was 90 g. For evaluation, the internal space consisting of a 100t press machine, core (lower mold) and cavity (upper mold) forms a cylindrical shape with a diameter of 100 mm, and the thickness of the top side of the cylindrical space on the cavity side A mold having a channel of 1.5 to 2 mm and a width of 50 mm was used. As evaluation of formability, 10 seconds after charging the laminate to the core, the core is raised and then pressurized at 10 MPa, and the flow length (mm) of the forming material flowing out into the flow path is measured did. Both the core cavity and the channels were heated to 140 ° C. The molding time was 120 seconds. It was judged that there is suitable moldability if the flow length is 420 mm or more, and it is judged that the moldability is excellent if it is 450 mm or more, and the moldability is particularly excellent if it is 480 mm or more.

<Preparation of matrix resin>
(Examples 1 to 5 and Comparative Examples 1 to 4)
Thermal polymerization initiation of component (A-4) in 100 parts by mass of one or two kinds of thermosetting resins which is a mixture of components (A-1) and (A-2) described in Tables 1 and 2 % Solution of 1,1-di (t-butylperoxy) cyclohexane as a dispersant (manufactured by NOF Corporation, product name: Perhexa C-75 (EB)) and 0.5 parts by mass of t-butylperoxyisopropyl A 74% by mass solution of carbonate (Akayaku Akzo Co., Ltd., product name: Kayacaron BIC-75) 0.5 parts by mass, and a phosphate ester derivative composition as an internal mold release agent (Axel Plastic Research Laboratory, product name) 0.5 parts by mass of MOLD WIZ INT-EQ-6, 0.02 parts by mass of 1,4-benzoquinone as a polymerization inhibitor, and molecular sieve (A Honeywel) as a moisture absorbent Company Inc. UOP L-POWDER) 1.2 parts by mass were blended, respectively, to obtain a sufficiently mixed and stirred pre matrix resin. Thereafter, the components (A-3) shown in Tables 1 and 2 were blended, and mixed and stirred for about 2 to 4 minutes to obtain matrix resins of the respective examples.
The neat resin viscosity of the thermosetting resin used in each example is shown in Tables 1 and 2.

As shown in Tables 3 to 5, when adjusting the matrix resin of each example, the blending amount of the component (A-3) with respect to 100 parts by mass of the thermosetting resin is a difference amount Y from the reference amount X [parts by mass] [Parts by mass] The amount of the component (A-3) was varied to adjust a plurality of types of matrix resins which were increased or decreased.
The reference amount X of the matrix resin of each example is as shown in Tables 3 to 5. For example, as shown in Table 3, in Example 1, the reference amount X [parts by mass] is 21.5. On the other hand, the difference amount Y [parts by mass] is 0.5 or 1.0, and the compounding amount of the component (A-3) is X [parts by mass], X + 1.0 [parts by mass], X-1. Five levels of matrix resin were prepared: 0 [parts by mass], X + 0.5 [parts by mass], and X-0.5 [parts by mass].
In Tables 3 to 5, when the compounding amount of the component (A-3) was reduced from the reference amount, “decreased” was described in the “Relation to the reference amount” column. On the other hand, when the compounding amount was increased from the reference amount, it was described as "increase" in the "relation to the reference amount" column.

The aging viscosity V1 (V1 _X , V1 _{X + Y} and V1 _XY ) and aging viscosity V2 were measured for a plurality of matrix resins different in the compounding amount of the component (A-3) obtained in each example, and thickening was performed. The ratio (V2 / V1) was calculated and the handleability and meltability were evaluated according to the method described above. Furthermore, based on the evaluation results of the handling and melting properties, the process window was evaluated according to the method described above.

In Examples 1 to 5, the aging viscosity V1 _X of the matrix resin in which the compounding amount of the component (A-3) is a reference amount X is 5 to 40 [× 10 ⁶ mPa · s], and (A-3) The aging viscosity (V1 _{X + 0.5} and V1 _X-0.5 ) of the matrix resin obtained by increasing or decreasing the blending amount of the component by 0.5 parts by mass from the reference amount X is 5 to 70 [× 10 ⁶ mPa · s] Y ≧ 0.5. Moreover, the evaluation result of the handling property is △ or 、, and the evaluation result of the meltability is ○, there are three or four levels of the matrix resin, and the process window was good.
Since the evaluation results of the process window were good, in Examples 1 to 5, production of the intermediate material was further performed. The intermediate material will be described later.

In Comparative Example 1, the aging viscosity V1 _X of the matrix resin in which the compounding amount of the component (A-3) is the reference amount X satisfies 5 to 40 [× 10 ⁶ mPa · s], and the component (A-3) The aging viscosity (V1 _{X + 0.5} ) of the matrix resin in which the compounding amount was increased by 0.5 parts by mass from the reference amount X satisfied 5 to 70 [× 10 ⁶ mPa · s]. However, the aging viscosity (V1 _X-0.5 ) of the matrix resin obtained by reducing the content of the component (A-3) by 0.5 parts by mass from the reference amount X is 5 to 70 [× 10 ⁶ mPa · s] Not satisfied, Y <0.5. In addition, the matrix resin whose handling property evaluation result is Δ or 、 and the meltability evaluation result is ○ is only one level which is the matrix resin when the reference amount X is blended, so the process window is good. It was not. Thereafter, the aging viscosity V2 of the matrix resin was measured to calculate the thickening ratio. From the evaluation result of the process window and the calculation result of the thickening ratio, in Comparative Example 1, the production of the intermediate material was not performed.

In Comparative Example 2, the aging viscosity V1 _X of the matrix resin in which the compounding amount of the component (A-3) is the reference amount X satisfies 5 to 40 [× 10 ⁶ mPa · s], and the component (A-3) The aging viscosity (V1 _{X + 0.5} and V1 _X-0.5 ) of the matrix resin in which the compounding amount is increased or decreased by 0.5 part by mass from the reference amount X satisfies 5 to 70 [× 10 ⁶ mPa · s], Y ≧ It was 0.5. Moreover, the evaluation result of the handling property is Δ or 、, and the evaluation result of the meltability is ○, there are three or more levels of the matrix resin, and the process window is good.
Thereafter, the aging viscosity V2 of the matrix resin was measured to calculate the thickening ratio, but the thickening ratio of the matrix resin satisfying the aging viscosity V1 of 5 to 40 [× 10 ⁶ mPa · s] tends to exceed 2.5. was there. From the calculation results of the thickening ratio, in Comparative Example 2, the production of the intermediate material was not performed.

In Comparative Example 3, the aging viscosity V1 _X of the matrix resin in which the compounding amount of the component (A-3) is the reference amount X satisfies 5 to 40 [× 10 ⁶ mPa · s], and the compounding of the component (A-3) The aging viscosity (V1 _{X + 0.5} and V1 _X-0.5 ) of the matrix resin whose amount is increased or decreased by 0.5 part by mass from the reference amount X satisfies 5 to 70 [× 10 ⁶ mPa · s], Y ≧ 0 It was .5. However, the matrix resin of which the evaluation result of the handleability is Δ or 、 and the melt evaluation result is ○ is only two levels, and the process window is not good.
Thereafter, the aging viscosity V2 of the matrix resin was measured to calculate the thickening ratio, but the thickening ratio of the matrix resin satisfying the aging viscosity V1 of 5 to 40 [× 10 ⁶ mPa · s] was all over 2.5. became. From the calculation results of the thickening ratio, in Comparative Example 3, the production of the intermediate material was not performed.
In Comparative Example 4, the aging viscosity V1 _X of the matrix resin in which the compounding amount of the component (A-3) is a reference amount _X is 5 to 40 [× 10 ⁶ mPa · s], and the component (A-3) is The aging viscosity ( _{V1X + 0.5} and _V1X-0.5 ) of the matrix resin in which the compounding amount is increased or decreased by 0.5 part by mass from the reference amount X satisfies 5 to 70 [× 10 ⁶ mPa · s], and Y ≧ It was 0.5. Moreover, the evaluation result of the handling property is △ or 、, and the evaluation result of the meltability is ○, there are three levels of matrix resin, and the process window was good.
Since the evaluation result of the process window was good, in Comparative Example 4, production of an intermediate material was further performed.

<Manufacturing of intermediate materials>
(Examples 1 to 5 and Comparative Example 4)
The matrix resin of Examples 1 to 5 in which the compounding amount of the component (A-3) is the reference amount X is made 0.5 to 3.0 mm in thickness on a polyethylene film (carrier film) using a doctor blade. Is applied, and a carbon fiber bundle of 15000 filaments (TR50S 15L, manufactured by Mitsubishi Chemical Corporation) is chopped to a length of 25 mm on the carbon fiber so that the basis weight of the carbon fiber is substantially uniform, And, the carbon fibers were scattered so that the directions of the carbon fibers become random, and deposited in a sheet. Then, another polyethylene carrier film coated with the same matrix resin to a thickness of 0.5 to 3.0 mm is superposed so that the matrix resin is in contact with the carbon fiber bundle, and passed between the pair of rolls. The mixture was pressed to impregnate sheet-like carbon fiber bundles from above and below with a matrix resin to obtain an intermediate material precursor. The obtained intermediate material precursor was allowed to stand at 23 ° C. for 168 hours to sufficiently thicken the matrix resin to obtain an intermediate material.

Here, the viscosity Vs of the matrix resin immediately after mixing and stirring the component (A-3) at the time of preparation of the matrix resin, and the viscosity V10 of the matrix resin when 10 minutes have elapsed from immediately after mixing and stirring are measured. The viscosity was calculated. In all cases, the initial viscosity ratio was as low as 1.20 or less, which was a good result. The results are shown in Table 6.
In Example 1 and Comparative Example 4, the intermediate material precursor A and the intermediate material A having a basis weight of 3000 ± 300 g / m ² and a carbon fiber content of 50 mass%, and a basis weight of 2800 ± 280 g / m ² And the intermediate material precursor B and the intermediate material B which are 60 mass% in carbon fiber content rate were manufactured. In Examples 2 to 5, the same intermediate material precursor A and intermediate material A as in Example 1 were produced.

For the obtained intermediate material precursor and the intermediate material, the impregnation evaluation was performed according to the method described above. As shown in Table 6, in Examples 1 to 5, the impregnating properties of the intermediate material precursor A and the intermediate material A were good. Moreover, although the impregnatability of the intermediate material precursor B and the intermediate material B in Examples 1 to 5 was good, the intermediate material precursor B and the intermediate material B in Comparative Example 4 tended to be slightly inferior to the infiltration property. .
The intermediate materials A obtained in Examples 1 to 5 were allowed to stand for 168 hours under an environment of 23 ° C. after production, and then the formability was evaluated according to the above-mentioned method. In all cases, there were no mold release defects and appearance defects, and the results were excellent in fluidity. On the other hand, although moldability evaluation was similarly implemented about comparative example 4, flowability was inferior.

<Production of molded plate>
(Examples 1 to 5 and Comparative Example 4)
The intermediate material A obtained in Examples 1 to 5 and Comparative Example 4 was molded to obtain a molded plate. Specifically, two sheets of intermediate material A of Examples 1 to 5 were cut out to a size of 200 mm to 250 mm to obtain a laminate. Next, using a mold with a cavity of 300 mm in length, 300 mm in width, and 2 mm in thickness, charge the laminate at a charge rate of 40 to 60% to a mold heated to 140 ° C, and close the mold quickly for molding It was heat compression molded for 5 minutes at a pressure of 8 MPa. Immediately before the completion of mold clamping, the pressure in the cavity was reduced to remove internal air.
The molded plates obtained in Examples 1 to 5 were free from breakage and warpage, and the surface was smooth. A bending test was performed using the formed plate. As shown in Table 6, all were favorable results.
Moreover, DMA measurement was performed on the molded plates obtained in Example 1, Example 5, and Comparative Example 4. The tan δmax of Example 1 was 161 ° C., and the tan δmax of Example 5 was 150 ° C., and all of them had good heat resistance.
On the other hand, the molded plate obtained in Comparative Example 4 had a tan δmax of 167 ° C., and the heat resistance was good, but as shown in Table 6, the bending strength was lowered as compared with Examples 1 to 5. The

From the above, the matrix resins of Examples 1 to 5 containing at least the components (A-1) to (A-4) in the present invention had good evaluation results of the process window. Furthermore, the thickening ratios of the matrix resins of Examples 1 to 5 were all 2.0 or less, and were low. Therefore, in Examples 1 to 5, it was possible to obtain an intermediate material which is less in product unevenness at the time of production and is excellent in moldability. Further, in the case of the molded plates of Examples 1 to 5, the results of the bending test were good, and a molded plate excellent in mechanical properties could be obtained. Furthermore, in the molded plates of Example 1 and Example 5, the results of the DMA measurement were good, and it was suggested that the molded plates of Examples 2 to 4 are similarly excellent in heat resistance.
Moreover, it was suggested from the results of the respective examples that the lower the neat resin viscosity of the thermosetting resin, the better the preparation of the intermediate material, in which the carbon fiber content of the intermediate material is high.

In Comparative Examples 1 and 3, since the isocyanate group content of the compound used as the component (A-3) is more than 30.5% by mass, the process window of the matrix resin composition was narrow.
In Comparative Example 2, since the isocyanate group content of the compound used as the component (A-3) was 30.5% by mass, the thickening ratio of the matrix resin composition tended to exceed 2.5. Therefore, there is a concern about the occurrence of product spots during the production of the intermediate material and the decrease in storage stability.
In Comparative Example 4, since the unsaturated polyester resin is not contained as the component (A-1), the impregnation property of the matrix resin at the time of producing the intermediate material, the fluidity at the time of forming the intermediate material are inferior, and the bending strength of the molded product is inferior. It was

Claims

Matrix resin containing at least a mixture of the following components (A-1) to (A-4):
(A-1) Component: Both an epoxy (meth) acrylate resin and an unsaturated polyester resin having one or more ethylenically unsaturated groups in one molecule and having an average number of hydroxyl groups of 1.8 to 4.
Component (A-2): Ethylenically unsaturated monomer.
Component (A-3): polyisocyanate having an isocyanate group content of 15 to 30.5% by mass and an average number of isocyanate groups of 1.8 to 2.4.
Component (A-4): thermal polymerization initiator.
The matrix resin according to claim 1, satisfying the following formulas (1) to (4).
5 ≦ V 1 X ≦ 40 (1)
Y ≧ 0.5 (2)
5 ≦ V1 X + Y ≦ 70 (3)
5 ≦ V1 XY ≦ 70 (4)
Matrix resin in which V1 X is a reference amount X (parts by mass) with respect to 100 parts by mass of a thermosetting resin consisting of a component having an ethylenically unsaturated group in the formula (1). Is left to stand at 23 ° C. for 168 hours, and the viscosity is [× 10 6 mPa · s], and the reference amount X is 10 to 40 parts by mass.
In the formula (2), Y is a difference [mass part] to increase or decrease the blending amount of the component (A-3) with respect to the reference amount X in the formula (1).
In the formula (3), V1 X + Y is a matrix resin in which the blending amount of the component (A-3) is increased relative to the reference amount X in the formula (1) by the amount of difference Y in the formula (2) [parts by mass] The resulting solution had a ripening viscosity [× 10 6 mPa · s] when allowed to stand at 23 ° C. for 168 hours.
In the formula (4), V1 XY decreased the blending amount of the component (A-3) with respect to the reference amount X in the formula (1) by the difference amount Y [parts by mass] in the formula (2) It is the ripening viscosity [× 10 6 mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 168 hours.
The matrix resin of Claim 1 or 2 which satisfy | fills following Formula (5) and the following Formula (6).
5 ≦ V1 ≦ 40 (5)
V2 / V1 ≦ 2.5 (6)
In Formula (5), V1 is the aging viscosity [× 10 6 mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 168 hours.
In the formula (6), V1 is the same as V1 in the formula (5), and V2 is a ripening viscosity [× 10 6 mPa · s] when the matrix resin is allowed to stand at 23 ° C. for 336 hours.
The matrix resin according to any one of claims 1 to 3, wherein the liquid polyisocyanate has one or more aromatic rings in the molecule.
The matrix resin according to any one of claims 1 to 4, which satisfies the following formula (7) and the following formula (8).
0.6 ≦ a1 / b ≦ 0.75 (7)
Vn ≦ 1000 (8)
In the formula (7), a1 is the content [g] of the component (A-1), and b is the content [g] of the thermosetting resin composed of the component having an ethylenically unsaturated group.
In Formula (8), Vn is a neat resin viscosity [mPa · s] of a thermosetting resin comprising a component having an ethylenically unsaturated group.
The matrix resin according to any one of claims 1 to 5, which satisfies the following formula (9).
V10 / Vs ≦ 1.20 (9)
In formula (9), Vs is the viscosity [mPa · s] immediately after mixing the pre-matrix resin obtained by removing the component (A-3) from the matrix resin and the component (A-3), and V10 is the above-mentioned It is a viscosity [mPa · s] when 10 minutes have elapsed by mixing the pre-matrix resin and the component (A-3).
A matrix resin according to any one of claims 1 to 6;
Carbon fiber bundles with a fiber length of 5 to 120 mm,
Intermediate materials, including
A molded article obtained by heating and pressing the intermediate material according to claim 7.
The molded article according to claim 8, wherein the temperature at which the loss tangent measured by dynamic viscoelasticity measurement at a frequency of 1 Hz shows a maximum value is 120 ° C or higher.