JP2013028715A - Thermosetting resin composition and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting resin composition which can suppress the increase in molecular weight upon preservation, is excellent in storage stability, and contains a thermosetting resin having a benzoxazine ring.SOLUTION: The thermosetting resin composition contains the thermosetting resin having the benzoxazine ring shown by the following formula (I), and a phenol compound. In the formula (I), Arexpresses a quadrivalent aromatic group, Rexpresses a 1-20C hydrocarbon group, and n expresses an integer of 2-500.

Description

  The present invention relates to a thermosetting resin composition and a method for producing the same.

  Thermosetting resin with benzoxazine ring in the molecular structure is superior to other thermosetting resins such as dimensional stability, electrical insulation and low water absorption in addition to heat resistance and flame retardancy. Therefore, it has been attracting attention as an electronic material such as various laminates and semiconductor encapsulants, and a binder such as a friction material and a grindstone.

  A thermosetting resin having a benzoxazine ring is a thermosetting resin having a structure in which an oxazine ring is adjacent to a benzene ring, and is usually produced by reacting a phenol compound, an amine compound, and an aldehyde compound.

The thermosetting resin having a benzoxazine ring exemplified in Scheme 1 can be produced using phenol as a phenol compound, aniline as an amine compound, and formaldehyde as an aldehyde compound. Then, as shown in Scheme 1, the thermosetting resin having a benzoxazine ring (left) causes ring-opening polymerization when heated to become polybenzoxazine (right). And in patent document 1, the dioxane etc. are disclosed as a solvent at the time of preparing a cast solution.
Scheme 1:

JP 2003-064180 A

  However, if the thermosetting resin having the benzoxazine ring described above is stored as it is after the synthesis, or if the thermosetting resin is dissolved in a solvent and stored as a solution, The weight average molecular weight (Mw) of the resin increases, and the solution itself may even gel. As a result, a decrease in handling property due to an increase in viscosity and a deterioration in compatibility with other compounding materials are caused.

  In addition, the weight average molecular weight of the thermosetting resin having a benzoxazine ring is also preserved when storing a dry film obtained by applying a cast solution in which a thermosetting resin having a benzoxazine ring is dissolved to a glass substrate and drying. (Mw) increases. As a result, film processability such as thermoforming is reduced.

  Thus, since the thermosetting resin having a benzoxazine ring has particularly poor storage stability in a solution state, after completion of the reaction in the solution in the production process or the like, a known method such as reprecipitation with a poor solvent is performed. It is necessary to recover the resin in the solution by a method, a concentration solidification method (solvent vacuum distillation), a spray drying method, or the like. However, there is a problem that the manufacturing process increases. In addition, it is necessary to refrigerate or store a dry film of a thermosetting resin having a benzoxazine ring. However, there is a problem in that this increases costs for storage.

  The present invention has been made in view of the above circumstances, and provides a thermosetting resin composition containing a thermosetting resin having a benzoxazine ring, which can suppress an increase in molecular weight during storage and is excellent in storage stability. With the goal.

  As a result of diligent research, the present inventor can solve the above-mentioned problems by using a thermosetting resin composition containing a thermosetting resin having a benzoxazine ring and a phenol compound having a specific structure. The present invention has been completed by finding out what can be done.

The present invention is as follows.
[1]
A thermosetting resin having a benzoxazine ring represented by the following formula (I);
A phenol compound represented by the following formula (II);
A thermosetting resin composition comprising:
In the formula (I), Ar ¹ represents a tetravalent aromatic group. R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms. n represents an integer of 2 to 500.
In formula (II), R ² and R ³ each independently represents an organic group having 1 to 20 carbon atoms.
[2]
The thermosetting resin composition according to [1], wherein the content of the phenol compound represented by the formula (II) in the thermosetting resin composition is 1 to 50 wt%.
[3]
A method for producing a thermosetting resin composition, comprising at least a step of mixing a thermosetting resin having a benzoxazine ring represented by the following formula (I) and a phenol compound represented by the following formula (II): .
In the formula (I), Ar ¹ represents a tetravalent aromatic group. R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms. n represents an integer of 2 to 500.
In formula (II), R ² and R ³ each independently represents an organic group having 1 to 20 carbon atoms.

  ADVANTAGE OF THE INVENTION According to this invention, the thermosetting resin composition containing the thermosetting resin which has the benzoxazine ring which can suppress the molecular weight increase at the time of a preservation | save, and is excellent in storage stability can be provided.

It is a proton nuclear magnetic resonance spectrum of the solution a thermosetting resin α produced in Example 1 is dissolved ⁽¹ H-NMR spectrum).

  Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the invention.

The thermosetting resin composition of this embodiment includes a thermosetting resin having a benzoxazine ring represented by the following formula (I) and a phenol compound represented by the following formula (II). It is a resin composition. Increasing the molecular weight of a thermosetting resin having a benzoxazine ring by containing a thermosetting resin having a benzoxazine ring represented by the following formula (I) and a phenol compound represented by the following formula (II) Can be suppressed.
In the formula (I), Ar ¹ represents a tetravalent aromatic group. R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms. n represents an integer of 2 to 500.
In formula (II), R ² and R ³ each independently represents an organic group having 1 to 20 carbon atoms.

(Thermosetting resin with benzoxazine ring)
The thermosetting resin having a benzoxazine ring used in the present embodiment may be a thermosetting resin having a benzoxazine ring represented by the following formula (I).
In the formula (I), Ar ¹ represents a tetravalent aromatic group. R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms. n represents an integer of 2 to 500.
Ar ¹ may be a tetravalent aromatic group, and the type thereof is not particularly limited. However, from the viewpoint of heat resistance, Ar ¹ is preferably at least one selected from the group consisting of the following (G1).
G1:
In the group (G1), X represents an aliphatic or aromatic organic group having a linear bond, a branched structure, or a cyclic structure, which may include a direct bond, or a hetero element or a functional group. Here, each of the aliphatic organic group or the aromatic organic group may have a substituent. * Represents a bonding site to the oxygen atom at the 1-position of the oxazine ring, and ** represents a bonding site to the carbon atom at the 4-position of the oxazine ring.

X only needs to be bonded at the ortho position, the meta position, or the para position with respect to the bonding positions of the left and right phenolic hydroxyl groups. The bonding position of X is the same bonding position in the left and right benzene rings. It may be different and may be different, such as the ortho position and the para position. X is preferably at least one selected from the group consisting of (G2) below.
G2:
In the group (G2), * represents a binding site.

From the viewpoint of heat resistance, X is more preferably at least one selected from the group consisting of the following (G2a).
G2a:
In the group (G2a), * represents a binding site.

R ¹ in the formula (I) is a hydrocarbon group having 1 to 20 carbon atoms, and any type of hydrocarbon group is not limited. Specifically, organic of an aliphatic or aromatic diamine residue having a linear, branched, or cyclic structure, which may contain a substituted or unsubstituted heteroelement having 1 to 20 carbon atoms. Represents a group. R ¹ is preferably an organic group represented by at least one selected from the group consisting of the following (G3) from the viewpoint of heat resistance, and is represented by the following formula (1), formula (2), formula (3) And an organic group represented by at least one selected from the group consisting of formula (4).
G3:
In the group (G3), * represents a binding site.

  In Formula (2), Y represents an aliphatic or aromatic organic group having a straight bond, a branched structure, or a cyclic structure, which may include a direct bond, or a hetero element or a functional group. Each of the aliphatic or aromatic organic groups may have a substituent. The substituent is not particularly limited, and examples thereof include an aliphatic hydrocarbon group having a linear, branched, or cyclic structure having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group. Y may be bonded at any of the ortho, meta, and para positions with respect to the right and left bond positions, and the bond position of Y may be the same position in the left and right benzene rings, They may be different as in the ortho and para positions.

Y may be at least one organic group selected from the group consisting of (G4) below.
G4:
In the group (G4), * represents a binding site.

R ¹ is represented by at least one selected from the group consisting of the following formula (1), formula (2a), formula (3), and formula (4) from the viewpoint of heat resistance of a cured body such as a film. More preferably, it is an organic group.
In formula (2a), Y represents a methylene chain or a direct bond, and * represents a binding site.
In Formula (3) and Formula (4), * represents a binding site.

  In the formula (I), n is an integer of 2 to 500, and preferably 2 to 400, more preferably 2 to 300, from the viewpoint of compatibility with other materials.

(Phenol compound)
The phenol compound used in the present embodiment may be a phenol compound represented by the following formula (II).
In formula (II), R ² and R ³ each independently represents an organic group having 1 to 20 carbon atoms.

R ² and R ³ may be independently an organic group having 1 to 20 carbon atoms, and the kind thereof is not particularly limited, but R ² and R ³ are each independently independent from the viewpoint of storage stability. And at least one selected from the group consisting of a methyl group, an ethyl group, a propyl group, a t-butyl group, a t-octyl group, an α-cumyl group, and a phenyl group.

  Specific examples of the phenol compound represented by the formula (II) include phenol, p-cresol, 4-ethylphenol, 4-propylphenol, 4-t-butylphenol, 4-t-octylphenol, and 4-α-cumyl. Phenol, o-cresol, 2-ethylphenol, 2-propylphenol, 2-phenylphenol, 2,4-xylenol and the like can be mentioned. Among these, 2,4-xylenol is preferable from the viewpoint of storage stability. The phenol compound represented by the formula (II) may be used alone or in combination of two or more.

  In the thermosetting resin composition of the present embodiment, the mechanism for suppressing the increase in molecular weight is not clear, but is estimated as follows. By reacting the reaction active site of the thermosetting resin having a benzoxazine ring with the phenol compound represented by the formula (II), the reaction between the reaction active sites of the thermosetting resin having a benzoxazine ring is suppressed, As a result, it is presumed that the increase in molecular weight is suppressed (however, the action of this embodiment is not limited to this).

  In the thermosetting resin composition of the present embodiment, the content of the phenol compound represented by the formula (II) is preferably 1 to 50 wt%, more preferably 1 to 40 wt%, More preferably, it is 30 wt%. By making content of the phenolic compound represented by Formula (II) into the said range, the storage stability of the thermosetting resin composition of this embodiment can be made further excellent.

  In the thermosetting resin composition of the present embodiment, in addition to the above-described components, an organic solvent, a curing accelerator, a flame retardant, an inorganic filler, a release agent, an adhesion imparting agent, a surfactant, Coloring agents, coupling agents, leveling agents, other thermosetting resins, and the like can be added.

  Examples of the organic solvent include ethylene glycol monomethyl ether, N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), γ-butyrolactone, toluene, xylene, mesitylene, Examples thereof include pseudocumene, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, (MIBK), cyclopentanone, cyclohexanone, tetrahydrofuran (THF), 1,4-dioxane, and ethyl acetate. Among these, from the viewpoint of compatibility with other compounding agents, ethylene glycol monomethyl ether, N, N-dimethylformamide (DMF), toluene, xylene, methyl ethyl ketone (MEK), methyl isobutyl ketone, (MIBK), and cyclohexanone are included. Ethylene glycol monomethyl ether and N, N-dimethylformamide (DMF) are more preferable.

  The inorganic filler is not particularly limited, and various inorganic fillers can be used. For example, powder of silica, alumina, zircon, calcium silicate, calcium carbonate, potassium titanate, silicon carbide, silicon nitride, aluminum nitride, boron nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, titania, etc. Or a bead or glass fiber formed by spheroidizing these. Among these, silica is preferable from the viewpoint of versatility and the like. These may be used individually by 1 type and may be used in combination of 2 or more type.

(Production method)
The manufacturing method of the thermosetting resin composition of this embodiment mixes the thermosetting resin which has the benzoxazine ring represented by the said Formula (I), and the phenolic compound represented by the said Formula (II). Process. In the production method of the present embodiment, a thermosetting resin having a benzoxazine ring represented by the above formula (I) and a phenol compound represented by the above formula (II) are mixed, and then the mixture is dissolved in an organic solvent. The phenol compound represented by the above formula (II) is added and mixed in a solution in which the thermosetting resin having the benzoxazine ring represented by the above formula (I) is dissolved in an organic solvent. Alternatively, a thermosetting resin having a benzoxazine ring represented by the above formula (I) may be added to and mixed with a solution in which the phenol compound represented by the above formula (II) is dissolved in an organic solvent. Good. Examples of the organic solvent that can be used here include the organic solvents described above.

  The method of adding and mixing is not particularly limited, and for example, a stirrer, a stirrer (magnetic stirrer), a planetary stirrer, or the like can be used.

  In this embodiment, as a step of mixing the thermosetting resin having a benzoxazine ring represented by the above formula (I) and the phenol compound represented by the above formula (II), thermosetting having a benzoxazine ring. It is good also as a process of adding a phenol compound to the reaction solution of the reaction which manufactures a functional resin. This process is simple because the process for separating and purifying the thermosetting resin as a product can be simplified or omitted in the process for producing a thermosetting resin having a benzoxazine ring.

  Hereinafter, based on the manufacturing method of the thermosetting resin which has a benzoxazine ring, the manufacturing method of the thermosetting resin composition of this embodiment is demonstrated. In this embodiment, when performing from the manufacture of a thermosetting resin having a benzoxazine ring, a bifunctional phenol compound, a diamine compound, and an aldehyde compound are reacted in an organic solvent, and the thermosetting resin having the benzoxazine ring. And a step of adding a phenol compound represented by the formula (II) to the reaction solution. Since the phenol compound represented by the above formula (II) is a compound that suppresses the increase in molecular weight in the production process of the thermosetting resin having a benzoxazine ring, it is used in the production process of the thermosetting resin having a benzoxazine ring. It is preferable to add after completion | finish of the synthesis reaction of the thermosetting resin which has a benzoxazine ring. Thereby, the increase in molecular weight in the solution after reaction and the obtained dry film can be more effectively suppressed, and a thermosetting resin having a benzoxazine ring having a desired molecular weight can be produced efficiently and stably. it can. The timing of adding the phenol compound represented by the above formula (II) is not particularly limited, and may be added immediately after the reaction is completed, or after the reaction is completed, the reaction solution is cooled to room temperature and then added. May be.

  The method for producing a dry film is not particularly limited, and a solution in which a thermosetting resin having a benzoxazine ring represented by the above formula (I) and a phenol compound represented by the above formula (II) is dissolved is a glass substrate or It can obtain by apply | coating and drying to a base film. The drying method is not particularly limited, and the solvent can be volatilized while being heated or blown by standing at room temperature or using a drying oven.

  First, the manufacturing method of the thermosetting resin which has a benzoxazine ring is not specifically limited, A well-known method is employable. Specific examples of the production method include a method having a step of reacting a bifunctional phenol compound, a diamine compound and an aldehyde compound in an organic solvent.

It does not specifically limit as a bifunctional phenol compound, For example, the compound etc. which have two phenolic hydroxyl groups represented by following formula (5) are mentioned.
Formula (5):

HO-Ar ² -OH

In the formula (5), Ar ² represents an aromatic organic group that may contain a hetero element.

It does not specifically limit as a bifunctional phenol compound, For example, the compound etc. which are represented by following formula (6) or Formula (7) are mentioned.

In Formula (6), X ¹ represents an aliphatic or aromatic organic group having a linear bond, a branched structure, or a cyclic structure, which may contain a direct bond, or a hetero element or a functional group. Each of the aliphatic organic group and the aromatic organic group may have a substituent. The substituent is not particularly limited, and examples thereof include an aliphatic hydrocarbon group having a linear, branched, or cyclic structure having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group.

In the formula (6), X ¹ is ortho to the bond positions of the right and left of the phenolic hydroxyl groups, meta, need only be attached at any para-position, the binding position of X ¹ the left and right benzene In the ring, they may be at the same position or different as in the ortho position and the para position.

When the bifunctional phenol compound is a compound represented by the formula (6) and X ^{1 in} the formula is any ^one of the above organic groups, X ¹ is at least one selected from the group consisting of the following (G5) It is preferable that
G5:
In the group (G5), * represents a binding site to the aromatic ring in the formula (6).

Among these, it is more preferable that X ¹ is any one of the group consisting of the following (G5a).
G5a:
In the group (G5a), * represents a binding site to the aromatic ring in the formula (6).

  Specific examples of the bifunctional phenol compound are not particularly limited. For example, 4,4′-dihydroxydiphenyl-2,2-propane (bisphenol A), 4,4 ′-[1,3-phenylenebis (1- Methyl-ethylidene)] bisphenol (bisphenol M), 4,4 ′-[1,4-phenylenebis (1-methyl-ethylidene)] bisphenol (bisphenol P), 4,4′-methylenediphenol (bisphenol F), Bis (4-hydroxyphenyl) sulfone (bisphenol S), 4,4′-dihydroxybenzophenone (DHBP), 4,4′-biphenol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxy Naphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxy Futaren, benzenediol (hydroquinone), 1,3-benzenediol (resorcinol), 1,2-benzenediol (catechol), and the like. Among these, 4,4′-dihydroxybenzophenone (DHBP), 4,4′-biphenol, and bis (4-hydroxyphenyl) sulfone are used from the viewpoint of further improving the heat resistance of a molded body such as a film, which will be described later, and a cured body. (Bisphenol S), 1,4-benzenediol (hydroquinone), 4,4′-dihydroxydiphenyl-2,2-propane (bisphenol A), 4,4 ′-[1,3-phenylenebis (1-methyl-) Ethylidene)] At least one selected from the group consisting of bisphenol (bisphenol M) is preferred. A bifunctional phenol compound may be used individually by 1 type, and may use 2 or more types together.

It does not specifically limit as a diamine compound, For example, the compound etc. which have two amino groups represented by following formula (7) are mentioned.
Formula (7):

H ₂ N—R ⁴ —NH ₂

In Formula (7), R ⁴ represents an aliphatic or aromatic organic group having a linear, branched, or cyclic structure that may contain a hetero element.

  Examples of the diamine compound include alicyclic diamine compounds, linear aliphatic diamine compounds, and aromatic diamine compounds.

It does not specifically limit as an alicyclic diamine compound, For example, the compound etc. which are represented by following formula (8) or Formula (9) are mentioned.

  The compounds represented by formula (8) and formula (9) may be cis isomer, trans isomer, or any mixture of cis isomer and trans isomer.

Although it does not specifically limit as a linear aliphatic diamine compound, For example, the compound etc. which are selected from the group which consists of the following (G6) are mentioned.
G6:

It does not specifically limit as an aromatic diamine compound, For example, the compound etc. which are represented by following formula (10) or Formula (11) are mentioned.

In Formula (11), X ² represents an aliphatic or aromatic organic group having a linear bond, a branched structure, or a cyclic structure, which may include a direct bond, or a hetero element or a functional group. Each of the aliphatic organic group and the aromatic organic group may have a substituent. The substituent is not particularly limited, and examples thereof include an aliphatic hydrocarbon group having a linear, branched, or cyclic structure having 1 to 20 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group.

In Formula (11), X ² may be bonded at any of the ortho, meta, and para positions with respect to the bonding positions of the left and right amino groups, and the bonding position of X ² is the right and left benzene rings. May be the same position, or may be different as in the ortho position and the para position.

When the diamine compound is a compound represented by the formula (11) and X ² is the organic group, X ² may be at least one organic group selected from the group consisting of (G7) below. Good.
G7:
In the group (G7), * represents a binding site to the aromatic ring in the formula (11).

The diamine compound is not particularly limited. For example, 3 (4), 8 (9), -bis (aminomethyl) tricyclo [5.2.1.0 ^2,6 ] decane, 2,5 (6)- Alicyclic diamine compounds such as bis (aminomethyl) bicyclo [2.2.1] heptane; 1,2-diaminoethane, 1,6-diaminohexane, 1,10-diaminodecane, 1,12-diaminododecane, Linear aliphatic diamine compounds such as 1,14-diaminotetradecane and 1,18-diaminooctadecane; p-phenylenediamine (PDA), 4,4′-diaminodiphenylmethane (MDA), 4,4′-diamino-3, 3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, 4,4′-diamino-3,3 ′, 5,5′-tetramethyldiphenylmethane, 4,4′-diamino-3,3 ′, 5,5′-tetraethyldiphenylmethane, 4,4′-diaminodiphenyl ether, 2,2′-bis [4- (4-aminophenoxy) phenyl] propane, 4,4 '-[1,3-phenylenebis (1-methyl-ethylidene)] bisaniline (bisaniline M), 4,4'-[1,4-phenylenebis (1-methyl-ethylidene)] bisaniline (bisaniline P), 1 , 3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4′-diaminobiphenyl, 4,4′-bis (4-aminophenoxy) biphenyl and the like Examples include diamine compounds. Among these, from the viewpoint of improving the heat resistance of a cured product such as a film, 3 (4), 8 (9), -bis (aminomethyl) tricyclo [5.2.1.0 ^2,6 ] decane, Consists of 2,5 (6) -bis (aminomethyl) bicyclo [2.2.1] heptane, p-phenylenediamine (PDA), 4,4′-diaminodiphenylmethane (MDA), 4,4′-diaminobiphenyl At least one selected from the group is preferred. A diamine compound may be used individually by 1 type, and may use 2 or more types together.

  The amount of the diamine compound used is preferably 0.1 to 2 mol, more preferably 0.3 to 1.8 mol, and more preferably 0.5 to 1.5 mol with respect to 1 mol of all bifunctional phenol compounds. More preferably it is. For example, when the compound represented by the formula (6) is used as the bifunctional phenol compound, it means that the amount of the diamine compound used is within the above range with respect to 1 mol of the compound represented by the formula (6). By making the usage-amount of the diamine compound with respect to 1 mol of bifunctional phenolic compounds 2 mol or less, gelatinization of a reaction solution can be suppressed effectively. By making the amount of the diamine compound used relative to 1 mol of the bifunctional phenol compound 0.1 mol or more, the bifunctional phenol compound is sufficiently reacted without remaining to further increase the molecular weight of the thermosetting resin having a benzoxazine ring. Can be made. That is, polymerization can be performed while maintaining the repeating unit of the benzoxazine ring structure without proceeding with the ring-opening reaction of the benzoxazine ring as described above (see, for example, Scheme I). Thereby, the thermosetting resin which has a benzoxazine ring in a repeating unit, ie, has a benzoxazine ring before thermosetting of a prepolymer type, can be obtained efficiently.

  The aldehyde compound is not particularly limited, and examples thereof include acetaldehyde, benzaldehyde, formaldehyde and the like. Among these, at least formaldehyde is preferable from the viewpoint of increasing the molecular weight of the thermosetting resin having a benzoxazine ring. As formaldehyde, it can be used in the form of paraformaldehyde which is a polymer thereof, formalin which is in the form of an aqueous solution, or the like. Moreover, it can also be used as a hemiacetal obtained by reacting formaldehyde or paraformaldehyde with an alcohol. Although it does not specifically limit as alcohol in that case, Methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol etc. are mentioned. Among these, methanol is preferable from the viewpoint of ease of distillation. Alcohol may be used individually by 1 type and may use 2 or more types together.

  The amount of the aldehyde compound used is preferably 4 to 8 mol, more preferably 4 to 7 mol, and still more preferably 4 to 6 mol with respect to 1 mol of the diamine compound. By making the usage-amount of an aldehyde compound 8 mol or less, the influence on a human body and an environment can be reduced. By making the usage-amount of an aldehyde compound 4 mol or more, the thermosetting resin which has a benzoxazine ring can be made high molecular weight further.

  In the method for producing a thermosetting resin having a benzoxazine ring, a monofunctional phenol compound may be added and reacted together with a bifunctional phenol compound. When a monofunctional phenol compound is used in combination, a polymer having a reactive end sealed with a benzoxazine ring is generated. As a result, the molecular weight during the synthesis reaction can be controlled and gelation of the solution can be prevented. Moreover, the sealing of the reactive terminal can also improve the storage stability of the obtained thermosetting resin having a benzoxazine ring and prevent insolubilization. As the monofunctional phenol compound here, a phenol compound represented by the above formula (II) may be used.

  It does not specifically limit as a monofunctional phenol compound, For example, phenol, o-cresol, m-cresol, p-cresol, p-tert-butylphenol, p-octylphenol, p-cumylphenol, dodecylphenol, o-phenyl Phenol, p-phenylphenol, 1-naphthol, 2-naphthol, m-methoxyphenol, p-methoxyphenol, m-ethoxyphenol, p-ethoxyphenol, 3,4-dimethylphenol, 3,5-dimethylphenol, etc. Can be mentioned. Among these, phenol, o-cresol, m-cresol, p-cresol, 1-naphthol, and 2-naphthol are preferable from the viewpoint of the end-capping effect. A monofunctional phenol compound may be used individually by 1 type, and may use 2 or more types together.

  Although the usage-amount of a monofunctional phenol compound is not specifically limited, Although it may change also with the kind of monofunctional phenol to be used, 0.5 mol or less is preferable with respect to 1 mol of bifunctional phenol compounds normally. When the amount of the monofunctional phenol compound used is 0.5 mol or less relative to 1 mol of the bifunctional phenol compound, the thermosetting resin having a benzoxazine ring can be made to have a high molecular weight during the synthesis reaction. The remaining amount can be reduced by sufficiently reacting the functional phenol compound.

  According to the above-described method, the gelation of the resin produced can be suppressed even during the reaction of the thermosetting resin, and a thermosetting resin having a benzoxazine ring that has been appropriately increased in molecular weight can be obtained. And the molecular weight increase at the time of preservation | save of a solution, a dry film, etc. can also be suppressed by further adding the phenolic compound represented by Formula (II).

  The amount of the organic solvent used for the reaction of the bifunctional phenol compound, the diamine compound and the aldehyde compound is not particularly limited, but the molar concentration of the bifunctional phenol compound is preferably 0.1 to 5.0 mol / L. More preferably, it is 0.2 to 4.0 mol / L, and still more preferably 0.3 to 3.0 mol / L. When the molar concentration of the bifunctional phenol compound is 0.1 mol / L or more, the synthesis reaction rate of the thermosetting resin having a benzoxazine ring can be further accelerated, and the synthesis efficiency can be increased. When the molar concentration of the bifunctional phenol compound is 5.0 mol / L or less, during the synthesis reaction of the thermosetting resin having a benzoxazine ring, the gelation of the reaction solution can be more effectively suppressed, Insolubilization of the thermosetting resin having a benzoxazine ring can be prevented.

  The order of adding and mixing the raw materials such as the bifunctional phenol compound, the diamine compound, and the aldehyde compound is not particularly limited. For example, the bifunctional phenol compound, the diamine compound, and the aldehyde compound may be sequentially added to and mixed with the mixed solvent. Each raw material may be added and mixed at once. It is preferable to first mix the bifunctional phenol compound and the diamine compound in the reaction solvent.

  In this embodiment, in order to efficiently mix and dissolve the raw materials, it is preferable to warm the solvent. Moreover, you may add and mix a bifunctional phenol compound etc. suitably, stirring a solvent using a stirrer, a stirring element, etc. During the reaction, an inert gas such as nitrogen gas may be purged as necessary. Although it does not specifically limit as a method of a heating process, For example, after using a temperature controller, such as an oil bath, to raise at a stretch to predetermined temperature, the method of keeping constant at the temperature etc. is mentioned.

  The temperature during the heating treatment is not particularly limited, but the reaction solution temperature is preferably in the range of 10 to 150 ° C, more preferably in the range of 30 to 150 ° C, and in the range of 50 to 150 ° C. Is more preferable. By setting the reaction solution temperature to 10 ° C. or higher, the synthesis reaction of the thermosetting resin having a benzoxazine ring can be effectively promoted, and the reaction efficiency can be further increased. By setting the reaction solution temperature to 150 ° C. or lower, gelation of the reaction solution can be effectively suppressed, and insolubilization of the resulting thermosetting resin having a benzoxazine ring can be effectively prevented. While the reaction solution is heated, the solvent may be refluxed.

  From the viewpoint of improving the reaction efficiency, it is preferable to heat the mixed solution of the bifunctional phenol compound, the diamine compound, and the reaction solvent in advance before adding the aldehyde compound. The phenol compound represented by the above formula (II) can be added after the completion of the reaction to efficiently promote the reaction without inhibiting the increase in the molecular weight of the thermosetting resin having a benzoxazine ring.

  In the manufacturing method of the thermosetting resin which has a benzoxazine ring, you may further have the process of distilling off the water to produce | generate. By distilling off the water produced by the reaction, the synthesis reaction time of the thermosetting resin having a benzoxazine ring can be shortened, and the efficiency of the reaction can be improved. The method and timing for distilling off the produced water are not particularly limited, and can be performed, for example, by azeotroping with the solvent in the reaction solution. More specifically, the generated water can be distilled off by using an isobaric dropping funnel with a cock, a Dimroth cooler, a Dean-Stark device, or the like. Moreover, you may remove the water to produce | generate out of the system by reducing the pressure inside the reaction vessel during the reaction step.

  Although the processing time of a heating process is not specifically limited, For example, it is preferable that it is about 1 to 15 hours after a heating start, and about 2 to 10 hours are more preferable. After heating, the reaction solution may be allowed to cool by being released from contact with a temperature controller such as an oil bath, or may be cooled using a refrigerant or the like.

  In the manufacturing method of the thermosetting resin which has a benzoxazine ring, you may further have the process of wash | cleaning the mixed solution which complete | finished reaction with basic aqueous solution after synthetic reaction. By further performing the washing step, the unreacted bifunctional phenol compound or monofunctional phenol compound can be effectively removed from the reaction solution. After washing with a basic aqueous solution in the washing step, ions derived from the basic aqueous solution such as sodium ions can be removed by washing several times with distilled water or the like.

  The basic aqueous solution used for the washing is not particularly limited as long as it is an aqueous solution in which a basic compound is dissolved in water. Examples of the basic compound include sodium hydroxide, potassium hydroxide, calcium hydroxide and the like. Among these, sodium hydroxide is preferable from the viewpoint of versatility.

  The thermosetting resin having a benzoxazine ring thus obtained has a moderately high molecular weight. Therefore, physical properties such as heat resistance and flexibility such as glass transition temperature and thermal decomposition temperature of a final product such as a film obtained by the subsequent ring-opening reaction can be improved. Moreover, according to this manufacturing method, since gelation of the reaction solution can be suppressed, even a thermosetting resin having a rigid skeleton such as a benzophenone skeleton or a biphenyl skeleton (for example, see formula (6)) is manufactured. be able to.

  The weight average molecular weight (Mw) in terms of polystyrene obtained by gel permeation chromatography (GPC) measurement of a thermosetting resin having a benzoxazine ring is preferably 2000 to 300,000, more preferably 2000 to 100,000. Yes, more preferably 3000-50000, and still more preferably 4000-30000. The thermosetting resin having a benzoxazine ring obtained by the above-described production method or the like has a moderately high molecular weight. Here, “high molecular weight” means that a thermosetting resin having a benzoxazine ring in a repeating unit, that is, a prepolymer type benzoxazine ring before thermosetting, has a weight average molecular weight of 2000 to 2000. It means that it is controlled to about 300,000. A weight average molecular weight of 2000 or more is preferable because the heat resistance and flexibility of the final product obtained by the subsequent ring-opening reaction can be increased. When the composition of the present embodiment is a solution, the molecular weight is blown with compressed air or nitrogen gas using an air gun or the like to remove the liquid component and take out the resin component, It can be determined by measuring what is dissolved in the eluent. In the case of a dry film, it can be determined by collecting a part of the film and measuring it by dissolving it in an eluent such as DMF.

  The weight average molecular weight of the thermosetting resin can be measured by extracting a part of the solution from the resin synthesis reaction or from the obtained resin stock solution and performing gel permeation chromatography measurement. Moreover, in the case of a dry film, it can measure by extract | collecting a part of dry film and performing a gel permeation chromatography measurement.

  In the above method, a thermosetting resin having a benzoxazine ring can be obtained by using only a non-halogen substance as a material. Therefore, since the thermosetting resin having a benzoxazine ring obtained by the above method can have a structure that does not have halogen in the structure, it is not gelled and does not substantially contain halogen. -Friendly thermosetting resin composition can also be obtained. Furthermore, when the thermosetting resin composition of this embodiment is used as an insulating material, it is preferable because the electrical insulation can be further improved by substantially not containing halogen.

  In the thermosetting resin composition of the present embodiment, it can be molded into a molded body. Moreover, this can be hardened and it can be set as a hardening body. Such a molded body or cured body is obtained by molding or curing by a conventionally known method. The thermosetting resin composition of the present embodiment can be formed into a molded body or a cured body by, for example, ring-opening reaction of a benzoxazine ring, and can be used as an electronic component / electronic device and its material. Specifically, it can be suitably used as an electronic material such as a laminate or a semiconductor encapsulant, or a binder such as a friction material or a grindstone. In particular, it is suitable for applications such as multilayer substrates, laminates, sealants, adhesives and the like that require a low coefficient of thermal expansion (low CTE) and a low dielectric loss tangent. Examples of the electronic device include a mobile phone, a display device, an in-vehicle device, a computer, and a communication device. As an electronic component, it can be used for applications such as aircraft members, automobile members, building members, etc., and forms a circuit that can flow direct current or alternating current by using as a heat-resistant adhesive for conductive materials, especially metal fillers. You may use for an application. As an electronic device, it can use as materials, such as a mobile phone, a display apparatus, vehicle equipment, a computer, a communication apparatus, for example.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention more concretely, this invention is not limited to a following example. In addition, the evaluation method and measurement method used for a present Example are as follows.

[Measurement of weight average molecular weight (Mw)]
High-performance liquid chromatograph system, manufacturer: SHIMADZU
System controller: SCL-10A VP
Liquid feeding unit: LC-10AD VP
VP degasser: DGU-12A
Differential refractometer (RI) detector: RID-10A
Autoinjector: SIL-10AD VP
Column oven: CTO-10AC VP
Column: Tosoh TSKgel α-4000 (exclusion limit molecular weight 1000000) × 2 (in series)
Column temperature: 50 ° C
Flow rate: 0.8 mL / min Eluent: DMF (manufactured by Wako Pure Chemical Industries, no stabilizer, for HPLC), LiBr 10 mmol / L sample: 0.1 wt%
Detector: RI
A calibration curve was prepared using standard polystyrenes (manufactured by Tosoh Corporation) having Mw of 707,000, 354000, 189000, 98900, 37200, 17100, 9830, 5870, 2500, 1050, and 500, respectively, under the above measurement conditions. And the weight average molecular weight (Mw) of the sample was measured based on the polypolystyrene conversion value obtained by the gel permeation chromatography measurement. In the case of preparing a measurement sample, when the solution is a solution, the solution is sprayed with compressed air using an air gun to remove the solvent, and the resulting resin is used as an eluent (N, N-dimethylformamide: DMF). Dissolved. When measuring a dry film, a part of the film was collected and the obtained film was dissolved in an eluent (DMF) so as to have a predetermined concentration.

[Measurement of ¹ H-NMR]
¹ H-NMR was measured at a sample concentration of 2 wt% using the following measuring apparatus and solvent.
Measuring device: JEOL, ECX400 (400MHz)
Solvent: heavy dimethyl sulfoxide (DMSO; manufactured by Sigma-Aldrich; containing 0.05% by volume TMS (tetramethylsilane))

(Synthesis of thermosetting resin α having benzoxazine ring)
In a 300 mL flask at room temperature, 100.0 mL of ethylene glycol monomethyl ether (hereinafter referred to as “MC”) (product name “Hisolv MC” manufactured by Toho Chemical Industry Co., Ltd.), N, N-dimethylformamide (hereinafter referred to as “MC”). DMF ”) 67.0 mL (manufactured by Gordo), xylene 46.0 mL (manufactured by Wako Pure Chemical Industries, Ltd.), 4,4′-dihydroxybenzophenone (hereinafter referred to as“ DHBP ”) 86.3 g (0.40 mol) , Wako Pure Chemical Industries, Ltd.), p-phenylenediamine (hereinafter referred to as “PDA”) 46.6 g (0.43 mol, manufactured by Daishin Kasei Kogyo Co., Ltd., product name “Paramine”), 2-naphthol 9.4 g (0.065 mol, manufactured by Wako Pure Chemical Industries, Ltd.) was added, and nitrogen gas purge was started into the system (flow rate: 150 mL / min). Subsequently, the flask was immersed in an oil bath, and after the temperature of the reaction solution reached 45 ° C., 117.1 g of Formit M (46.4% formaldehyde component, 45.0% methanol component, manufactured by Koei Chemical Co., Ltd., product name) "KOEI holmit M") was added dropwise. After completion of the dropwise addition, the flask was depressurized to 0.05 MPa, and reacted at a reaction solution temperature of 75 ° C. for 4 hours. The reaction solution thus obtained was cooled to room temperature to obtain a solution a in which the product benzoxazine thermosetting resin α was dissolved. The obtained thermosetting resin α had a weight average molecular weight (Mw) of about 6,000. FIG. 1 shows a proton nuclear magnetic resonance spectrum ( ¹ H-NMR spectrum) of the solution a in which the thermosetting resin α is dissolved.
Oxazine ring of DHBP_PDA Methylene proton peak at the 2-position of the oxazine ring: 5.46 ppm
Methylene proton peak at the 4-position of the oxazine ring: 4.65 ppm
Oxazine ring of 2-naphthol_PDA Methylene proton peak at the 2-position of naphthoxazine ring: 5.42 ppm
Methylene proton peak at the 4-position of the naphthoxazine ring: 4.88 ppm

Composition of solution a in which thermosetting resin α as product is dissolved Solution a in which thermosetting resin α is dissolved is measured in a glass container, and the glass container is not covered (leave open). ), Placed in a vacuum oven heated to 160 ° C., continued to reduce pressure with a vacuum pump for 11 hours, and the solvent was distilled off under reduced pressure to obtain a solid content. From the difference in weight before and after that, the weight of the solid content was determined. As a result, the solid content (thermosetting resin α content) was 60 wt%.
The content of MC as a solvent was 18 wt%, and the content of DMF was 22 wt%. The solvent composition was calculated from the ¹ H-NMR integration ratio of solution a.

<Example 1>
0.4 g of 2,4-xylenol (manufactured by Konan Chemical Co., Ltd.) is added to 11.2 g of the solution a in which the thermosetting resin α is dissolved (content of resin α: 6.7 g), and THINKY Co., Ltd. Awatori Netaro ARE-310 was stirred for 30 minutes to obtain Solution A.

<Example 2>
0.84 g of 2,4-xylenol (manufactured by Konan Chemical Co., Ltd.) is added to 10.4 g (content of resin α: 6.2 g) in which the thermosetting resin α is dissolved, and THINKY Awatori Netaro ARE-310 was stirred for 30 minutes to obtain Solution B.

The solutions a, A and B were stored overnight at 60 ° C. and 1 atm, and the state of each solution was observed. The results of solutions a, A and B are shown below.
Solution a: Gelled.
Solution A: Fluidity was maintained. A part of the solution after storage overnight was collected and subjected to GPC measurement. As a result, Mw of the thermosetting resin having a benzoxazine ring was about 14,000.
Solution B: Fluidity was maintained. A part of the solution after overnight storage was collected and subjected to GPC measurement. As a result, the Mw of the thermosetting resin having a benzoxazine ring was about 10,000.

<Example 3>
0.1 g of 2,4-xylenol (manufactured by Konan Chemical Co., Ltd.) is added to 8.6 g of the solution a in which the thermosetting resin α is dissolved (content of resin α: 5.2 g), and THINKY Co., Ltd. Awatori Netaro ARE-310 was stirred for 30 minutes to obtain Solution C. The obtained solution C was cast on a PET film and dried in an oven at 90 ° C. for 3 minutes to obtain a dry film C. The thickness of the obtained film was 40 μm.

<Example 4>
0.2 g of 2,4-xylenol (manufactured by Konan Chemical Co., Ltd.) is added to 7.5 g of the above solution a in which thermosetting resin α is dissolved (content of resin α: 4.5 g), and THINKY Co., Ltd. Awatori Netaro ARE-310 was stirred for 30 minutes to obtain Solution D. The obtained solution D was cast into a PET film in the same manner as in Example 3, and dried in an oven at 90 ° C. for 3 minutes to obtain a dry film D. The thickness of the obtained film was 40 μm.

<Comparative Example 1>
7.0 g of the above solution a in which the thermosetting resin α is dissolved (resin α content: 4.2 g) is cast into a PET film in the same manner as in Example 3 and is placed in an oven at 90 ° C. for 3 minutes. Dried film a was obtained by drying. The thickness of the obtained film was 40 μm.

  The dried films C, D, and a were stored under conditions of 23 ° C. and 1 atm, and the time-dependent change in Mw of each film was traced by GPC measurement.

Dry film C: Mw about 6,000 after 1 day, Mw about 8,000 after 3 days, Mw about 10,000 after 5 days.
Dry film D: Mw after 6,000 about 6,000, Mw after 3 days, 6,000, Mw after 5 days, about 7,000.
Dry film a: Mw about 18,000 after 1 day, insolubilized in DMF after 3 days.

  From the above results, it was confirmed that each example can sufficiently suppress an increase in molecular weight and is excellent in storage stability.

  The thermosetting resin composition of the present invention can suppress an increase in molecular weight during storage and is excellent in storage stability. Therefore, the thermosetting resin composition is used as an electronic material such as a laminate or a semiconductor encapsulant, or as a binder such as a friction material or a grindstone. be able to.

Claims (3)

A thermosetting resin having a benzoxazine ring represented by the following formula (I);
A phenol compound represented by the following formula (II);
A thermosetting resin composition comprising:
In the formula (I), Ar ¹ represents a tetravalent aromatic group. R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms. n represents an integer of 2 to 500.
In formula (II), R ² and R ³ each independently represents an organic group having 1 to 20 carbon atoms.   The thermosetting resin composition according to claim 1, wherein the content of the phenol compound represented by the formula (II) in the thermosetting resin composition is 1 to 50 wt%. A method for producing a thermosetting resin composition, comprising at least a step of mixing a thermosetting resin having a benzoxazine ring represented by the following formula (I) and a phenol compound represented by the following formula (II): .
In the formula (I), Ar ¹ represents a tetravalent aromatic group. R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms. n represents an integer of 2 to 500.
In formula (II), R ² and R ³ each independently represents an organic group having 1 to 20 carbon atoms.