JP6445848B2 - Maleimide compound-containing resin composition, cured product obtained by curing the same, method for producing cured product, and fiber-reinforced resin molded article - Google Patents

Description

  The present invention is a maleimide compound-containing resin composition that can be suitably used for a semiconductor sealing material, a printed wiring board material, a fiber-reinforced composite material, an adhesive material, and the like, a cured product obtained by curing it, a method for producing a cured product, And a fiber-reinforced resin molded body.

  Conventionally, thermosetting resin compositions such as epoxy resin compositions have been used for semiconductor sealing materials, printed wiring board materials, fiber-reinforced composite materials, adhesive materials, and the like. In recent years, in each of these applications, the use environment of the material has become more severe, and in particular, improvement of the heat resistance of the material is required. For example, Patent Document 1 proposes a phenol-based oligomer obtained by polycondensation reaction of a divalent allyl-substituted phenol compound and an aldehyde compound in which an allyl group is substituted for divalent phenol.

  However, although the conventional epoxy resin composition is excellent in electrical characteristics and mechanical characteristics, it cannot always be said that the heat resistance is sufficient. Therefore, a bismaleimide resin composition using a bismaleimide compound as a main ingredient has been proposed as a thermosetting resin composition having high heat resistance.

  Patent Document 2 discloses a composition containing bismaleimide and 2-allylphenol novolac, and Example 2 contains 50:50 (weight: methylenedianiline-derived bismaleimide and 2-allylphenol novolak). Examples used in weight) are disclosed.

International Publication No. 2012/057228 JP-A-2-110158

  However, Patent Document 1 does not discuss a resin composition of a phenolic oligomer and a maleimide compound or a cured product thereof. Further, in Patent Document 2, 2-allylphenol novolak acts as a reactive diluent for the composition, and the heat resistance of the cured product is not sufficient.

  The present invention has been made in view of the above problems, and provides a maleimide compound-containing resin composition having excellent heat resistance, a cured product obtained by curing the resin composition, a method for producing the cured product, and a fiber-reinforced resin molded article. The purpose is to do.

  As a result of intensive investigations to achieve the above object, the inventors of the present invention have a phenolic oligomer composed of a divalent allyl-substituted phenol compound in which an allyl group is substituted on a divalent phenol and at least one molecular structure. It has been found that the heat resistance of the maleimide compound-containing resin composition is excellent by including a maleimide compound having two maleimide groups, leading to the present invention.

That is, the present invention relates to the following matters.
1. A maleimide compound-containing resin composition comprising a phenolic oligomer represented by the following general formula (1) and a maleimide compound having at least two maleimide groups in one molecular structure.

(In the formula, n is an integer of 0 to 15,
R is an allyl group;
a1 and a3 are each independently 0, 1, 2 or 3,
Each a2 is independently 0, 1 or 2,
Each R ′ is independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group.
However, at least one of a1, any of a2, and a3 is 2. )

2. Item 2. The maleimide compound-containing resin composition according to Item 1, wherein the maleimide compound is a bismaleimide compound.
3. Ratio [number of maleimide group equivalents / number of allyl group equivalents] of the allyl group equivalent number of the phenolic oligomer represented by the general formula (1) and the maleimide group equivalent number of the maleimide compound is 0.50 to 1.50. Item 3. The maleimide compound-containing resin composition according to Item 1 or 2, which is formulated in a range.
4). The maleimide compound-containing resin composition according to any one of Items 1 to 3, further comprising a radical initiator.
5). Item 5. A cured product obtained by heat-treating the maleimide compound-containing resin composition according to any one of Items 1 to 4.
6). 5. A method for producing a cured product, wherein the maleimide compound-containing resin composition according to any one of Items 1 to 4 is heat-treated at a temperature of 150 to 280 ° C. to obtain a cured product.
7). 5. A fiber reinforced resin molded article, wherein the matrix resin comprises the maleimide compound-containing resin composition according to any one of Items 1 to 4.

  According to the present invention, excellent heat resistance includes a phenolic oligomer comprising a divalent allyl-substituted phenol compound in which an allyl group is substituted on a divalent phenol and a maleimide compound having at least two maleimide groups in one molecular structure. A maleimide compound-containing resin composition, a cured product obtained by curing the resin composition, a method for producing the cured product, and a fiber-reinforced resin molded article can be provided.

6 is a chart obtained by measuring dynamic viscoelasticity of a laminate obtained in Example 5. FIG.

  The maleimide compound-containing resin composition of the present invention contains a phenolic oligomer and a maleimide compound having at least two maleimide groups in one molecular structure.

  In the present invention, the phenolic oligomer is represented by the following general formula (1).

(In the formula, n is an integer of 0 to 15,
R is an allyl group;
a1 and a3 are each independently 0, 1, 2 or 3,
Each a2 is independently 0, 1 or 2,
Each R ′ is independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group.
However, at least one of a1, any of a2, and a3 is 2. )

  The phenolic oligomer represented by the general formula (1) has two phenolic hydroxyl groups on the benzene ring, 0, 1, 2 or 3, preferably 1, 2 or 3, more preferably 1 or 2. It contains a condensation unit of an aldehyde compound and a divalent phenol compound substituted with two, more preferably two allyl groups (hereinafter also referred to as a divalent allyl-substituted phenol compound).

  The phenol-based oligomer represented by the general formula (1) is a divalent compound unit derived from a divalent phenol compound substituted with two allyl groups (where a1, a2, and a3 are 2). Of all the structural units derived from phenolic compounds, preferably 50 to 100 mol%, more preferably 60 to 100 mol%, still more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, particularly preferably 95-100 mol%.

  In the phenol oligomer represented by the general formula (1), the structural unit derived from the divalent phenol compound is preferably a structural unit derived from resorcin or catechol, and more preferably a structural unit derived from resorcin. .

  In the phenolic oligomer represented by the general formula (1), a structural unit derived from a divalent phenol compound substituted with two allyl groups is 2,4-diallyl resorcin and / or 4,6-diallyl resorcin. What is the structural unit made from is preferable.

  The phenol-based oligomer represented by the general formula (1) may include a structural unit derived from a divalent phenol compound in which the allyl group is unsubstituted (a1, a2, and a3 are 0). In the present invention, a structural unit derived from a monovalent phenol compound in which one phenolic hydroxyl group and 0, 1, 2, or 3 allyl groups are substituted on the benzene ring does not hinder the effects of the present invention. It may be included within the range.

  R ′ in the phenolic oligomer represented by the general formula (1) is derived from an aldehyde compound, and R ′ is a hydrogen atom or an alkyl group or aryl group having 1 to 10 carbon atoms. From the viewpoint of heat resistance and low viscosity, a hydrogen atom or an alkyl group having 1 to 10 carbon atoms is preferable, and a hydrogen atom is more preferable.

  From the viewpoint of low viscosity, the degree of condensation n of the phenol oligomer represented by the general formula (1) is preferably 0 to 10, more preferably 0 to 7, and further preferably 0 to 5.

  In addition, the phenolic oligomer represented by the general formula (1) preferably has a rotational viscosity by an E-type viscometer at 25 ° C., preferably from 0.01 to 150 Pa · s, more preferably from the viewpoint of low viscosity. 0.01 to 130 Pa · s, more preferably 0.01 to 100 Pa · s, more preferably 0.01 to 80 Pa · s, still more preferably 0.01 to 70 Pa · s, particularly preferably. 0.01 to 60 Pa · s.

  Although the manufacturing method of the phenol-type oligomer represented by the said General formula (1) is not specifically limited, For example, it can manufacture by the well-known method of patent document WO2012 / 0572228A1, and can produce bivalent allyl. A method in which a phenol compound component containing a substituted phenol compound and a aldehyde compound are subjected to a condensation polymerization reaction is preferable.

  In the method for producing a phenol-based oligomer represented by the general formula (1), the divalent allyl-substituted phenol compound is obtained by subjecting the dihydric phenol resorcinol or the hydroxyl group of catechol to allyl ether conversion by a known method, and then Claisen rearrangement. Obtained. From the viewpoint of the low viscosity of the maleimide compound-containing resin composition and the heat resistance of the cured product, a divalent allyl-substituted phenol compound obtained by allylating resorcin is preferred, and a divalent phenol substituted with two allyl groups. The compounds 2,4-diallyl resorcin and / or 4,6-diallyl resorcin are more preferred.

  In the method for producing a phenolic oligomer represented by the general formula (1), the aldehyde compound is not particularly limited, but as the alkyl aldehyde, formaldehyde, hexanal and octanal, as the aromatic aldehyde, benzaldehyde, Examples include salicylaldehyde, parahydroxybenzaldehyde, and allylphenylaldehyde. From the viewpoint of the low viscosity of the maleimide compound-containing resin composition and the heat resistance of the cured product, formaldehyde is preferred.

  In the method for producing a phenol oligomer represented by the general formula (1), the molar ratio of the phenol compound to the aldehyde compound is preferably from the viewpoint of low viscosity of the maleimide compound-containing resin composition and heat resistance of the cured product. Is 1.2: 1 to 10: 1, more preferably 1.3: 1 to 9: 1, and still more preferably 1.4: 1 to 8: 1.

  In the phenolic oligomer represented by the general formula (1), one of the preferred embodiments is that 2,4-diallyl resorcin and 4,6-diallyl resorcinol, wherein the phenol compound component is a divalent allyl-substituted phenol compound. And a phenol compound component mainly composed of a mixture of two kinds of isomers and formaldehyde and a condensation polymerization reaction. Here, “based on two isomers” means that the total amount of the two isomers is 50 to 100 mol%, preferably 60 to 100 mol%, based on the total amount of the phenol compound component. More preferably, it means 70-100 mol%, More preferably, it is 80-100 mol%, Most preferably, it is 90-100 mol%, More preferably, it means 95-100 mol%. In addition, from the viewpoint of lowering the viscosity of the phenolic oligomer represented by the general formula (1), the phenol compound component used includes two types of isomers of 2,4-diallyl resorcin and 4,6-diallyl resorcin. When the main component is used, it is preferable that the proportion of 4,6-diallyl resorcin is small. The proportion of 4,6-diallyl resorcin in the phenol compound component is preferably 5 to 85 mol%, more preferably 10 to 80 mol%, still more preferably 15 to 75 mol%.

  In the present invention, the maleimide compound is preferably a bismaleimide compound having at least two maleimide groups represented by the following general formula (2) in one molecular structure.

(In the formula, each Y is independently a divalent group having one carbon-carbon double bond as the main chain.)

Specifically, bismaleimide compounds include 1,6-bismaleimide- (2,2,4-trimethyl) hexane, 1,6-bismaleimide- (2,4,4-trimethyl) hexane, N, N'-decamethylene bismaleimide, N, N'-octamethylene bismaleimide, N, N'-hexamethylene bismaleimide, N, N'-trimethylene bismaleimide, N, N'-ethylene bismaleimide, etc. The skeleton may have an aliphatic (acyclic) structure, and bis [(2,5-dioxo-2,5-dihydropyrrol-1-yl) methyl] bicyclo [2.2.1] heptane, N, N '-M-phenylene bismaleimide, 4,4'-diphenylmethane bismaleimide, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, , 4′-diphenylsulfide bismaleimide, 4-methyl-1,3-phenylenebismaleimide, 1,3-phenylenebismaleimide, 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane, 3, 3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide, 3,3′-dimethyl-4,4′-diphenylmethane bismaleimide, 1,3-bis (3-maleimidophenoxy) benzene, The skeleton of a compound such as 1,3-bis (4-maleimidophenoxy) benzene or 1,3-bis (3-maleimidophenoxy) benzene may have an aliphatic cyclic structure or an aromatic cyclic structure.
Among them, bis [(2,5-dioxo-2,5-dihydropyrrol-1-yl) methyl] bicyclo [2.2.1] heptane, 1,6-bismaleimide- (2,2,4-trimethyl) It is preferable that the skeleton of the compound selected from the group consisting of hexane and N, N′-hexamethylene bismaleimide has an aliphatic (non-cyclic) structure, or 4,4′-diphenylmethane bismaleimide, 4,4′- Diphenyl ether bismaleimide, 4,4′-diphenylsulfone bismaleimide, 4,4′-diphenyl sulfide bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,3-phenylene bismaleimide, 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane, 1,3-bis (4-maleimidophenoxy) benzene, 1,3 Which skeleton compound selected from the group consisting of bis (3-maleimido phenoxy) benzene having an aliphatic cyclic structure or aromatic ring structure are preferred.

  In the present invention, the maleimide compound is more preferably a bismaleimide compound represented by the following general formula (3).

(Wherein R1, R2, R3, and R4 are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,
X is —CH ₂ —, —C (CH ₃ ) ₂ —, —SO ₂ —, —SO—, —S—, or —O—. )

In the present invention, the maleimide compound is more preferably a bismaleimide compound in which X is represented by —CH ₂ — in the general formula (3). Although not particularly limited, specific examples include N, N′-4,4′-diphenylmethane bismaleimide, N, N ′-(3,3′-dimethyl-4,4′-diphenylmethane) bis. Maleimide, N, N ′-(3,3 ′, 5,5′-tetramethyl-4,4′-diphenylmethane) bismaleimide, N, N ′-(3,3′-diethyl-4,4′-diphenylmethane ) Bismaleimide, N, N ′-(3,3′-di-n-butyl-4,4′-diphenylmethane) bismaleimide, N, N ′-(3,3′-dimethyl-5,5′-diethyl -4,4'-diphenylmethane) bismaleimide, N, N '-(3,3', 5,5'-tetraethyl-4,4'-diphenylmethane) bismaleimide, etc., and these two or more are used in combination. It is also possible. Particularly preferred is N, N′-4,4′-diphenylmethane bismaleimide.

  In the present invention, one type of bismaleimide compound may be used alone, but two or more types of bismaleimide compounds may be mixed and used. From the viewpoint of improving heat resistance, a bismaleimide compound in which the skeleton of the compound has an aliphatic cyclic structure or an aromatic cyclic structure is preferable.

  In the present invention, the maleimide compound may have a polysiloxane structure in the chemical structure. For example, polysiloxane bismaleimide in which X in the general formula (3) is a divalent group having a polysiloxane structure represented by the following general formula (4) in the structure can also be used.

(In the formula, each R5 is independently an alkyl group having 1 to 3 carbon atoms or a phenyl group, and l is an integer of 1 to 30.)

In the maleimide compound-containing resin composition of the present invention, the compounding ratio of the phenolic oligomer represented by the general formula (1) and the maleimide compound having at least two maleimide groups in one molecular structure is represented by the general formula (1). The ratio [number of maleimide group equivalents / number of allyl group equivalents] of the allyl group equivalent number of the phenolic oligomer and the maleimide compound equivalent number of the maleimide compound is preferably 0.50 to 1.50, more preferably Is in the range of 0.70 to 1.40, more preferably 0.80 to 1.30, still more preferably 0.85 to 1.25, and particularly preferably 0.90 to 1.20.
If the [maleimide group equivalent number / allyl group equivalent number] is lower than 0.50, the heat resistance of the cured product of the maleimide compound-containing resin composition may be lowered, and if it is higher than 1.50, the maleimide compound-containing resin composition is obtained. In some cases, the viscosity of the liquid becomes high, or it becomes impossible to mix uniformly.

  In addition, the number of functional group equivalents such as the number of maleimide group equivalents and the number of allyl group equivalents is B / A (in the case where the functional group equivalent of the compound is A (g / eq) and the charge amount is B (g). When the purity of the compound is C%, it can be obtained by [B × C / 100] / A). That is, functional group equivalents such as maleimide group equivalent and allyl group equivalent represent the molecular weight of the compound per functional group, and the number of functional group equivalents refers to the number of functional groups per equivalent (preparation amount) of compound (equivalent weight). Number).

  The maleimide compound-containing resin composition of the present invention can suitably obtain a cured product by heat treatment without using a radical initiator or a curing accelerator, but contains a radical initiator as necessary. Also good. The radical initiator makes it possible to stably obtain a cured product having excellent characteristics by heat treatment at a relatively low temperature.

The radical initiator may be a conventionally known one, such as acyl peroxide, hydroperoxide, ketone peroxide, organic peroxide having t-butyl group, peroxide having cumyl group, etc. An organic peroxide etc. can be mentioned. Specific examples include, but are not limited to, benzoyl peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, lauroyl peroxide, di-t-butyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, cumene hydroperoxide. Preferable examples include oxide and dicumyl peroxide.
Although the usage-amount of a radical initiator is not specifically limited, It is 0.1-8 mass parts with respect to 100 mass parts of phenolic oligomers, Preferably it is 1-6 mass parts.

Examples of the curing accelerator include 2-ethyl-4-methylimidazole, 2-n-undecylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-methyl-2-methylimidazole. Preferred examples include imidazoles such as 1-isobutyl-2-methylimidazole.
Although the usage-amount of a hardening accelerator is not specifically limited, It is 0.01-5 mass parts with respect to 100 mass parts of phenolic oligomers, Preferably it is 0.1-2 mass parts.

  The cured product of the maleimide compound-containing resin composition of the present invention preferably contains a radical initiator or a curing accelerator from the viewpoints of high heat resistance (high glass transition temperature) and low linear expansion coefficient. Moreover, in the hardened | cured material of the maleimide compound containing resin composition of this invention, it is preferable not to contain a radical initiator or a hardening accelerator from a viewpoint of high intensity | strength and low water absorption.

  In the maleimide compound-containing resin composition of the present invention, additives such as inorganic or organic fillers, coupling agents, pigments, and dyes can be suitably used as necessary. An organic solvent can also be used.

The maleimide compound-containing resin composition of the present invention comprises a phenolic oligomer and a maleimide compound that is usually solid, a ratio of the number of allyl group equivalents of the phenolic oligomer and the number of maleimide group equivalents of the maleimide compound [maleimide group equivalent number / The number of allyl group equivalents] is in the range of 0.50 to 1.50, and the curing reaction does not substantially proceed at 30 to 150 ° C, preferably 50 to 140 ° C, more preferably 70 to 130 ° C. It can be suitably obtained by uniformly melt-mixing with stirring at a relatively low temperature. Although mixing time is not specifically limited, Preferably it is 0.1 to 5 hours, More preferably, it is about 0.2 to 2 hours. The maleimide compound-containing resin composition of the present invention obtained by melt mixing usually solidifies when cooled to room temperature, but the bismaleimide compound does not precipitate.
The maleimide compound-containing resin composition of the present invention is 30 ° C. or higher, preferably 40 ° C. or higher, more preferably 50 ° C. or higher, 100 ° C. or lower, preferably 90 ° C. even when solidified by cooling to room temperature after melt mixing. Hereinafter, it is easily fluidized at a relatively low temperature of 80 ° C. or less, more preferably 70 ° C. or less. For this reason, handling is very easy.
In addition, when melt mixing, a radical initiator, a curing accelerator, a filler, an additive, and the like can be blended together as necessary.

The maleimide compound-containing resin composition of the present invention can suitably obtain a cured product by heat treatment. The heat treatment is affected by the presence or absence of a radical initiator or a curing accelerator, but is preferably 150 to 280 ° C, more preferably 150 to 250 ° C, preferably 1 to 24 hours, more preferably 1 to 12 hours, It is good to carry out under normal pressure or under pressure using an autoclave. In particular, it is preferable that the temperature conditions include post-cure while raising the temperature stepwise.
The maximum temperature of the heat treatment is 150 to 200 ° C., preferably 150 to 180 ° C. from the viewpoint of low water absorption of the cured product, regardless of the presence or absence of a radical initiator or a curing accelerator. From the viewpoint of high strength, low elastic modulus and low linear expansion coefficient, a range of 200 to 250 ° C., preferably 200 to 240 ° C. is suitable.

  When the cured product obtained by curing the maleimide-containing resin composition of the present invention by heat treatment does not contain a radical initiator or a curing accelerator and is cured at a low temperature of 150 to 200 ° C., the maximum temperature of the heat treatment However, the glass transition temperature is 250 ° C. or higher, preferably 300 ° C. or higher, more preferably 350 ° C. or higher, and still more preferably 360 ° C. or higher.

By using the maleimide compound-containing resin composition of the present invention as a matrix resin, it is possible to suitably obtain a fiber-reinforced resin molded body by combining with a reinforcing fiber such as carbon fiber, glass fiber, alumina fiber, boron fiber, or aramid fiber. it can.
The compounding means may be a conventionally known method. The method of impregnating the reinforcing fiber with the maleimide compound-containing resin composition of the present invention is not particularly limited, but a method that does not use a solvent is preferable, and the maleimide compound-containing resin composition of the present invention is preferably 30 to 110 ° C., preferably 40 It is suitable to impregnate in a state of high fluidization by heating to a relatively low temperature of -100 ° C, more preferably 50-90 ° C, further preferably 50-80 ° C, particularly preferably 50-70 ° C. .
The prepreg obtained by impregnating the reinforcing fiber with the maleimide compound-containing resin composition of the present invention is usually 20 to 80% by mass, preferably 25 to 65% by mass, more preferably 30 to 50% by mass of the maleimide compound-containing resin. Contains the composition.
The prepreg can be cured by a known method to obtain a fiber reinforced resin molded product. For example, a fiber reinforced resin molded article can be suitably obtained by laminating a predetermined number of prepregs, pressurizing for 15 minutes with a hot press machine heated to 170 ° C., and then heat-treating at 200 ° C. for 90 minutes under normal pressure. it can. Also, for example, a predetermined number of prepregs are laminated, pressurized to ² to 10 kg / cm ² in an autoclave, 150 ° C. for 2 hours and then 175 ° C. for 3 hours, or 150 ° C. for 2 hours and then 175 ° C. for 3 hours. Next, a fiber-reinforced resin molded article can be suitably obtained by heat treatment at 230 ° C. for 4 hours.

  The maleimide compound-containing resin composition of the present invention can be suitably used in various applications such as a sealing material, a molding material, and an adhesive material. In particular, since the glass transition temperature of the cured product is high, it can be used for applications that could not be applied so far, such as fiber reinforced resin molding materials for aerospace materials.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

A method for measuring the characteristics used in the following examples is shown below.
(1) Viscosity Viscosity of the phenolic oligomer and allylphenol novolak was measured using a TVH type E type viscometer manufactured by Toki Sangyo Co., Ltd.
(Measurement condition)
Measurement temperature: 25 ° C
Sample volume: 1.2 mL

  The phenolic oligomers and maleimide compounds used in the following examples are as follows.

(1) Phenolic oligomer A
Phenol oligomer substantially represented by the following general formula (5)
(N is an integer from 0 to 15)
Rotational viscosity by E type viscometer at 25 ° C .: 3.9 Pa · s, hydroxyl group equivalent: 110 g / eq, allyl group equivalent: 110 g / eq
(2) Allylphenol novolak
(N is an integer from 0 to 20)
Rotational viscosity by E type viscometer at 25 ° C .: 23.6 Pa · s, hydroxyl group equivalent: 144 g / eq, allyl group equivalent: 144 g / eq
(3) Maleimide compound N, N′-4,4′-diphenylmethane bismaleimide BMI-1000 (purity: 92.8% by mass) manufactured by Daiwa Kasei Kogyo Co., Ltd.
Purity: 92.8%, maleimide group equivalent: 179 g / eq
(4) Radical initiator (dicumyl peroxide)
Park Mill D (purity: 99.9% by mass) manufactured by NOF Corporation

Example 1
100 parts by mass of phenol oligomer A is heated and stirred at 130 ° C., 200 parts by mass of N, N′-4,4′-diphenylmethane bismaleimide (BMI-1000 manufactured by Daiwa Kasei Kogyo) is added in several portions, In each case, the mixture was stirred and melted. After the melting temperature reached 130 ° C., the N, N′-4,4′-diphenylmethane bismaleimide was completely melted and stirred until the mixed bubbles disappeared to obtain a maleimide compound-containing resin composition.
The obtained maleimide compound-containing resin composition was vacuum degassed and then poured into a mold and cured by heat treatment at 150 ° C. for 2 hours and 175 ° C. for 3 hours, and the thickness was 4 mm × width 60 mm × length. A cured product of 150 mm was obtained.

(Example 2)
A cured product was obtained in the same manner as in Example 1 except that heat treatment was performed at 150 ° C. for 2 hours, 175 ° C. for 3 hours, and 230 ° C. for 4 hours.

Example 3
A cured product was obtained in the same manner as in Example 1 except that 5.5 parts by mass of the radical initiator dicumyl peroxide (DCPO) was added.

(Example 4)
A cured product was obtained in the same manner as in Example 2 except that 5.5 parts by mass of the radical initiator dicumyl peroxide (DCPO) was added.

(Comparative Example 1)
100 parts by weight of allylphenol novolak was heated and stirred at 130 ° C., and 152 parts by mass of N, N′-4,4′-diphenylmethane bismaleimide (BMI-1000 manufactured by Daiwa Kasei Kogyo) was added in several portions. It was stirred and melted each time. After the melting temperature reached 130 ° C., the N, N′-4,4′-diphenylmethane bismaleimide was completely melted and stirred until the mixed bubbles disappeared to obtain a maleimide compound-containing resin composition.
The obtained maleimide compound-containing resin composition was vacuum degassed and then poured into a mold and cured under curing conditions of 150 ° C. for 2 hours and 175 ° C. for 3 hours, thickness 4 mm × width 60 mm × length A cured product of 150 mm was obtained.

  The obtained cured product was evaluated by the following method.

(1) Bending strength and bending elastic modulus The cured products obtained in the examples and comparative examples were cut into a shape of 4 mm thick × 6 mm wide × 80 mm long to obtain a test piece. The stress and elastic modulus at the time of the three-point bending test of the test piece were measured under the following conditions using a universal testing machine with a thermostatic bath manufactured by A & D.
(Measurement condition)
Equipment: Universal testing machine with constant temperature bath manufactured by A & D, Inc. Test speed: 2 mm / min
Distance between fulcrums: 60mm
Test piece: 4 mm thick, 6 mm wide, 80 mm long
Atmosphere: Room temperature (25 ° C)
(2) Glass transition temperature (Tg) (DMA method (tensile method))
The cured products obtained in Examples and Comparative Examples were cut into shapes of thickness 1 to 1.5 mm × width 4 mm × length 40 to 50 mm to obtain test pieces. The storage elastic modulus of the cured product was measured under the following conditions using a dynamic viscoelasticity measuring device RSA-G2 manufactured by TA Instruments. The glass transition temperature (Tg) was defined as the temperature at the intersection where the two linear portions with respect to the storage elastic modulus change curve were extended.
(Measurement condition)
Apparatus: Dynamic viscoelasticity measuring apparatus RSA-G2 manufactured by TA Instruments
Temperature rising condition: 3 ° C per minute
Measurement upper limit: 400 ° C
Test piece: thickness 1 to 1.5 mm, width 4 mm, length 40 to 50 mm
Atmosphere: Nitrogen 30ml / min
(3) Linear expansion coefficient The hardened | cured material obtained in the Example and the comparative example was cut into the shape of thickness 10mm * width 4mm * length 6mm, and it was set as the test piece. The linear expansion coefficient in the temperature range below the glass transition temperature of the test piece was measured under the following conditions using TA-60 manufactured by Shimadzu Corporation.
(Measurement condition)
Apparatus: TA-60 manufactured by Shimadzu Corporation
Temperature rising condition: 3 ° C per minute
Measurement upper limit: 400 ° C
Test piece: 10 mm thick x 4 mm wide x 6 mm long
Atmosphere: Nitrogen 30ml / min
(4) 5% mass reduction temperature (measurement conditions)
Equipment: TG-DTA manufactured by Shimadzu Corporation
Temperature rising condition: 10 ° C / min Measurement upper limit: 500 ° C
Sample amount: 10 mg
Atmosphere: Under nitrogen flow of 55 mL / min (5) Water absorption rate The cured products obtained in the examples and comparative examples were cut into a shape of 4 mm thickness × 15 mm width × 30 mm length to obtain a test piece. The obtained test piece, weight (W ₁₎ was measured, and held for 24 hours in pure water heated to a temperature of 95 ° C., then after wiping off water removed from the pure water, its mass (W ₂ ) Was measured. The water absorption was calculated from the following formula.
Water absorption (%) = {W ₂ (g) −W ₁ (g)} / W ₁ (g) × 100

  Table 1 shows the compositions and evaluation results of Examples and Comparative Examples.

From Example 1, when phenolic oligomer A is used, even if it is a cured product that does not contain a radical initiator or a curing accelerator and is cured at a low temperature of 175 ° C., the glass transition temperature is the highest. Is 360 ° C. or higher, and the glass transition temperature of the cured product is significantly improved by 130 ° C. or higher compared to Comparative Example 1 using an allylphenol novolac resin.
From the comparison between Example 1 and Example 3 or the comparison between Example 2 and Example 4, from the viewpoint of heat resistance (high glass transition temperature) and low linear expansion coefficient, radical initiators and curing accelerators are used. It turns out that it is more preferable to contain. In addition, it is understood that it is preferable not to contain a radical initiator or a curing accelerator from the viewpoint of high strength and low water absorption.
From the comparison between Example 3 and Example 4, when the maximum temperature of the heat treatment contains a radical initiator or a curing accelerator, it is 150 to 200 ° C. from the viewpoint of low water absorption of the cured product, preferably The range of 150 to 180 ° C is suitable, and it can be seen that the range of 200 to 250 ° C, preferably 200 to 240 ° C is suitable from the viewpoint of the high strength, low elastic modulus and low linear expansion coefficient of the cured product. .
From the comparison between Example 1 and Example 2, the maximum temperature of the heat treatment is 150 to 200 ° C., preferably 150 from the viewpoint of low water absorption of the cured product when it does not contain a radical initiator or a curing accelerator. The range of -180 degreeC is suitable, and the range of 200-250 degreeC, Preferably it is 200-240 degreeC from a viewpoint of the high intensity | strength of a hardened | cured material, a low elasticity modulus, and a low linear expansion coefficient.

Next, examples of a prepreg using the maleimide compound-containing resin composition of the present invention and a laminate (copper-clad laminate) which is a fiber-reinforced resin molded article using the prepreg will be described. First, the evaluation method of the laminate used in the following examples is shown below.
(1) Peel strength A laminate obtained by forming a strip-like copper foil having a width of 10 mm by etching was used as a test piece. Using an autograph (“AG-5000D” manufactured by Shimadzu Corporation), the 90 ° copper foil peel strength was measured at a test speed of 50 mm / min.
(2) Glass transition temperature Using a dynamic viscoelastic device (TA Instruments (RSA-G2)), the laminate obtained by removing the copper foil by etching and cutting out to 10 mm × 40 mm was increased at 3 ° C./min. Measured at temperature rate. Moreover, let the temperature of the intersection which extended two linear parts with respect to the change curve of a storage elastic modulus be glass transition temperature (Tg).

The materials used in the following examples are shown below.
(1) Phenolic oligomer B
Phenol oligomer substantially represented by the following general formula (5)
(N is an integer from 0 to 15)
Rotational viscosity by E type viscometer at 25 ° C .: 3.9 Pa · s, hydroxyl group equivalent: 108 g / eq, allyl group equivalent: 108 g / eq
(2) Maleimide compound N, N′-4,4′-diphenylmethane bismaleimide BMI-1000 manufactured by Daiwa Kasei Kogyo Co., Ltd.
Purity: 92.8% by mass, maleimide group equivalent: 179 g / eq
(3) Radical initiator (dicumyl peroxide)
NOF Corporation Park Mill D (Purity: 99.9% by mass)
(4) Glass cloth Non-alkali treated glass cloth M2116: Arisawa Manufacturing Co., Ltd. (5) Copper foil Electrolytic copper foil CF-T9B-THE: Fukuda Metal Foil Powder Co., Ltd., thickness 35 μm

(Example 5)
100 parts by mass of phenol oligomer B was heated and stirred at 130 ° C., and 179 parts by mass of N, N′-4,4′-diphenylmethane bismaleimide (BMI-1000 manufactured by Daiwa Kasei Kogyo) was added in several portions. In each case, the mixture was stirred and melted. After the melting temperature reached 130 ° C., the mixture was stirred until the N, N′-4,4′-diphenylmethane bismaleimide was completely melted and there were no mixed bubbles. Next, the temperature of the mixture was set to 100 ° C., 7.5 parts by mass of dicumyl peroxide was added, and the mixture was further stirred to obtain a maleimide compound-containing resin composition.
The obtained maleimide compound-containing resin composition was impregnated with a glass cloth of 150 mm × 95 mm at 100 ° C. to obtain a prepreg. Next, after four prepregs are stacked, the copper-clad laminate is formed by sandwiching between copper foils, pressurizing with a hot press heated to 170 ° C. for 15 minutes, and heat-treating at 200 ° C. for 90 minutes under normal pressure. Obtained. An unnecessary portion of the copper foil on the surface of the copper-clad laminate was removed with an etching solution, and the laminate after the cleaning was evaluated. The evaluation results are shown in Table 2. Moreover, the measurement result of the storage elastic modulus, loss elastic modulus, and tan-delta which measured the laminated body with the dynamic viscoelasticity apparatus is shown in FIG.

  From the chart of measuring the dynamic viscoelasticity of the laminate of FIG. 1, no change curve is observed in the storage elastic modulus in the measurement temperature range, so that the glass transition temperature of the laminate exceeds at least 350 ° C. I understand.

  As described above, when the maleimide compound-containing resin composition of the present invention was used, a copper-clad laminate as a fiber-reinforced resin molded body could be obtained without using a solvent. Moreover, it turned out that the obtained copper-clad laminated body is excellent in heat resistance.

  According to the present invention, excellent heat resistance includes a phenolic oligomer comprising a divalent allyl-substituted phenol compound in which an allyl group is substituted on a divalent phenol and a maleimide compound having at least two maleimide groups in one molecular structure. A maleimide compound-containing resin composition can be obtained.

Claims (7)

A maleimide compound-containing resin composition comprising a phenolic oligomer represented by the following general formula (5) and a maleimide compound having at least two maleimide groups in one molecular structure.
  The maleimide compound-containing resin composition according to claim 1, wherein the maleimide compound is a bismaleimide compound. The ratio [number of maleimide group equivalents / number of allyl group equivalents] of the allyl group equivalent number of the phenolic oligomer represented by the general formula (5) and the maleimide group equivalent number of the maleimide compound is 0.50 to 1.50. The maleimide compound-containing resin composition according to claim 1 or 2, which is formulated in a range.   The maleimide compound-containing resin composition according to claim 1, further comprising a radical initiator.   Hardened | cured material formed by heat-processing and curing the maleimide compound containing resin composition in any one of Claims 1-4.   The manufacturing method of the hardened | cured material characterized by obtaining the hardened | cured material by heat-processing the maleimide compound containing resin composition in any one of Claims 1-4 at the temperature of 150-280 degreeC.   A fiber reinforced resin molded article, wherein the matrix resin comprises the maleimide compound-containing resin composition according to any one of claims 1 to 4.