WO2014057973A1 - Thermosetting resin and thermosetting resin composition - Google Patents

Abstract

Provided are a thermosetting resin having excellent heat resistance, a low coefficient of thermal expansion, and excellent moldability, and a thermosetting resin composition used for the resin. This thermosetting resin is characterized in being obtained by polymerizing a mixture containing a compound having a specific structure, another compound having a specific structure in a molar quantity 0.2-0.5 times that of the above-mentioned compound, and a cyanic acid ester.

Description

Thermosetting resin and thermosetting resin composition

The present invention relates to a thermosetting resin excellent in heat resistance, a low coefficient of thermal expansion, and moldability, and a thermosetting resin composition used for the resin.
This application claims priority on October 11, 2012 based on Japanese Patent Application No. 2012-2226075 for which it applied to Japan, and uses the content here.

In power devices used for electric vehicles and hybrid vehicles, high-efficiency operation at high temperatures is essential. With the conventional insulation and sealing technology in such power devices, it is difficult to obtain the required performance that satisfies both the mechanical load on the connection part and the heat resistance, and a new high heat resistance An encapsulant is required.
Moreover, in order to prevent the crack which arises from the shrinkage | contraction by a thermal cycle as a performance of a sealing material, the low thermal expansion coefficient is required.

Polybenzoxazine is a thermosetting resin obtained by ring-opening polymerization of benzoxazine, which is a monomer having a cyclic moiety, and is expected as a novel phenol resin that can overcome the drawbacks of conventional phenol resins.
Polymerization of benzoxazine is ring-opening polymerization, and the resulting resin not only has the same heat resistance, flame retardancy, and electrical properties as conventional phenolic resins, but also requires no polymerization catalyst, and is free from molecular design. Advantages such as high degree, few by-products, and good dimensional stability are attracting attention.
Further, benzoxazine is advantageous in that the aromatic ring in the structure causes stacking in the polymer, and thus the coefficient of thermal expansion of the cured resin is low. From these characteristics, utilization of polybenzoxazine as the sealing material is expected.

Furthermore, in addition to such polybenzoxazine, a resin having a further improved heat resistance is disclosed by polymerizing a mixture containing benzoxazine and bismaleimide (see, for example, Non-Patent Document 1). .

However, since the resin described in Non-Patent Document 1 has a high melting point of bismaleimide and requires a high temperature for the melt mixing of benzoxazine and bismaleimide, it is still from the viewpoint of obtaining a resin excellent in moldability. There is room for improvement.

This invention is made | formed in view of the said situation, Comprising: The thermosetting resin excellent in heat resistance, a low thermal expansion coefficient, and a moldability, and the thermosetting resin composition used for the said resin are provided. For the purpose.

[1] The thermosetting resin according to an embodiment of the present invention is 0.2 to 0.5 with respect to the compound represented by the following general formula (1) and the compound represented by the following general formula (1). A mixture containing a double molar amount of the compound represented by the following general formula (2) and a cyanate ester is polymerized.

[Wherein, X ¹ and X ² are each independently an alkylene group having 1 to 10 carbon atoms, a group represented by the following general formula (3), a formula “—SO ₂ —” or “—CO—” Or a single bond. ]

[Wherein Y is a hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring, and n is an integer of 1 or more. ]
[2] In the thermosetting resin according to an embodiment of the present invention, X ¹ and X ² are each independently a linear or branched alkylene group having 1 to 3 carbon atoms, or the following formula (i): The thermosetting resin of [1], which is a group represented by any one of (iii) to (iii), is preferable.

[3] The thermosetting resin according to an embodiment of the present invention includes 0.3 to 10 times the molar amount of the cyanate ester with respect to the compound represented by the general formula (1). 2] is preferable.
[4] The thermosetting resin composition according to the embodiment of the present invention is 0.2 to 0 with respect to the compound represented by the following general formula (1) and the compound represented by the following general formula (1). A 5-fold molar amount of the compound represented by the following general formula (2) and a cyanate ester are included.

[Wherein, X ¹ and X ² are each independently an alkylene group having 1 to 10 carbon atoms, a group represented by the following general formula (3), a formula “—SO ₂ —” or “—CO—” Or a single bond. ]

[Wherein Y is a hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring, and n is an integer of 1 or more. ]
[5] In the thermosetting resin composition according to an embodiment of the present invention, X ¹ and X ² are each independently a linear or branched alkylene group having 1 to 3 carbon atoms, or the following formula ( The thermosetting resin composition [4] which is a group represented by any one of i) to (iii) is preferable.

[6] In the thermosetting resin composition according to the embodiment of the present invention, the mixture contains 0.3 to 10 times the molar amount of the cyanate ester relative to the compound represented by the general formula (1). It is preferable that it is the thermosetting resin composition of [4] or [5] containing.
[7] The semiconductor encapsulant according to the embodiment of the present invention is preferably a semiconductor encapsulant including the thermosetting resin composition of [4] to [6].

According to the thermosetting resin of the present invention, since it is excellent in heat resistance, low thermal expansion coefficient, and moldability, it is suitably used as a sealing material for power devices for electric vehicles and hybrid vehicles.
According to the thermosetting resin composition of the present invention, it is possible to provide a thermosetting resin excellent in heat resistance, a low coefficient of thermal expansion, and moldability.

FIG. 6 is a diagram showing the results of differential scanning calorimetry in Examples 1 to 5 and Comparative Example 1 of the present invention. FIG. 6 is a diagram showing the results of FT-IR measurement in Examples 1 to 5 and Comparative Example 1 of the present invention. FIG. 6 is another diagram showing the results of FT-IR measurement in Examples 1 to 5 and Comparative Example 1 of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with specific examples.
[Thermosetting resin composition]
The thermosetting resin composition of the present embodiment has a molar amount of 0.2 to 0.5 times the amount of the compound represented by the following general formula (1) and the compound represented by the general formula (1). A compound represented by the following general formula (2) and a cyanate ester are included.

[Wherein, X ¹ and X ² are each independently an alkylene group having 1 to 10 carbon atoms, a group represented by the following general formula (3), a formula “—SO ₂ —” or “—CO—” Or a single bond. ]

[Wherein Y is a hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring, and n is an integer of 1 or more. ]

[Compound represented by the general formula (1)]
In the general formula (1), X ¹ is an alkylene group having 1 to 10 carbon atoms, a group represented by the general formula (3), a group represented by the formula “—SO ₂ —” or “—CO—”. , An oxygen atom, or a single bond.

The alkylene group for X ¹ is preferably a linear or branched alkylene group.
The number of carbon atoms of the alkylene group in X ¹ is preferably 1 to 10, more preferably 1 to 7, and particularly preferably 1 to 3.
Specific examples of the linear alkylene group include methylene group, ethylene group, n-propylene group (trimethylene group), n-butylene group (tetramethylene group), n-pentylene group (pentamethylene group), n -Hexylene group (hexamethylene group), n-heptylene group, n-octylene group, n-nonylene group, n-decanylene group, and the like.
Examples of the branched alkylene group include a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, and a decanylene group. Specifically, —C (CH ₃ ) ₂ — (isopropylene group), —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ) (CH ₂ CH ₃ ) — An alkylmethylene group such as —C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) — or —C (CH ₂ CH ₃ ) ₂ —; —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH An alkylethylene group such as (CH ₃ ) —, —C (CH ₃ ) ₂ CH ₂ —, —CH (CH ₂ CH ₃ ) CH ₂ —, or —C (CH ₂ CH ₃ ) ₂ —CH ₂ —, etc. Can be mentioned.
Preferable examples of the alkylene group for X ¹ include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.

In the group represented by the general formula (3), Y is a hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring, and n is an integer of 1 or more.
The hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring may be composed only of an aromatic ring, or may have a hydrocarbon group other than the aromatic ring. Y may have one aromatic ring or two or more aromatic rings, and in the case of two or more, these aromatic rings may be the same or different. The aromatic ring may be either a monocyclic structure or a polycyclic structure.
Preferred hydrocarbon groups having 6 to 30 carbon atoms having an aromatic ring include compounds having an aromatic ring such as benzene, biphenyl, naphthalene, anthracene, fluorene, phenanthrene, indacene, terphenyl, acenaphthylene, or phenalene. , A divalent group obtained by removing two hydrogen atoms from these nuclei.
Moreover, these aromatic hydrocarbon groups may have a substituent. Here, that the aromatic hydrocarbon group has a substituent means that part or all of the hydrogen atoms constituting the aromatic hydrocarbon group are substituted by the substituent. Examples of the substituent include an alkyl group.
The alkyl group as a substituent is preferably a chain alkyl group. The number of carbon atoms is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 4. Specific examples of the substituent that the aromatic hydrocarbon group has include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, and a sec-butyl group.

Y preferably has a group obtained by removing two hydrogen atoms from benzene, biphenyl or naphthalene. The group represented by the general formula (3) is more preferably a group represented by any of the following formulas (i) to (iii).

　　　　　　　　　　　　　　　　　 

In the group represented by the general formula (3), n is preferably an integer of 1 to 5, more preferably an integer of 1 to 3, and particularly preferably 1 or 2.

In this embodiment, in the compound represented by the general formula (1), the X ¹ is a linear or branched alkylene group having 1 to 3 carbon atoms, or the above formulas (i) to (iii). It is preferable that it is group represented by either.

Specific examples of the compound represented by the general formula (1) are shown in the following formulas (1-1) and (1-2), but the compounds used in the present embodiment are not limited to the following examples.

　　　　　　　　　　　　　　　　　 

　　　　　　　　　　　　　　　　　 

That is, in one embodiment of the thermosetting resin composition of the present invention, the compound represented by the general formula (1) is a straight chain having 1 to 3 carbon atoms or X ¹ in the general formula (1) A compound which is a branched alkylene group, a compound wherein X ¹ in the general formula is a group represented by any one of the formulas (i) to (iii), and a compound represented by the general formula (1-1) And at least one compound selected from the group consisting of the compound represented by the general formula (1-2), the compound represented by the general formula (1-1), and More preferably, it is at least one compound selected from the group consisting of compounds represented by formula (1-2).

[Compound represented by formula (2)]
In the general formula (2), X ² is an alkylene group having 1 to 10 carbon atoms, a group represented by the general formula (3), a group represented by the formula “—SO ₂ —” or “—CO—”. , An oxygen atom, or a single bond.

X ² in the general formula (2) is the same as X ¹ in the general formula (1).
X ¹ and X ² may be the same as or different from each other.

In this embodiment, in the compound represented by the general formula (2), the X ² is a linear or branched alkylene group having 1 to 3 carbon atoms, or the above formulas (i) to (iii). It is preferable that it is group represented by either.

Specific examples of the compound represented by the general formula (2) are shown in the following formulas (2-1) and (2-2), but the compounds used in the present embodiment are not limited to the following examples.

　　　　　　　　　　　　　　　　　 

　　　　　　　　　　　　　　　　　 

In this embodiment, a compound represented by the following general formula (4) is not used. Compared with the compound represented by the general formula (4), a resin having a higher heat resistance can be obtained by using the compound represented by the general formula (2).

[Wherein, X ² has the same meaning as X ² in the general formula (2). ]

That is, in one embodiment of the thermosetting resin composition of the present invention, the compound represented by the general formula (2) is a compound in which X ² in the general formula (2) is a straight chain having 1 to 3 carbon atoms or A compound which is a branched alkylene group, a compound wherein X ² in the general formula is a group represented by any one of the formulas (i) to (iii), and a compound represented by the general formula (2-1) And at least one compound selected from the group consisting of the compound represented by the general formula (2-2), the compound represented by the general formula (2-1), and More preferably, it is at least one compound selected from the group consisting of compounds represented by formula (2-2).

The content of the compound represented by the general formula (2) in the thermosetting resin composition of the present embodiment is such that the molar ratio with respect to the compound represented by the general formula (1) is 0.00. 2 to 0.5 times. By being in this range, there is an advantage that high heat resistance can be obtained while maintaining a low coefficient of thermal expansion. Outside this range, at least any one of these physical properties may be lowered, which is not preferable.

[Cyanate ester]
The cyanate ester is necessary for lowering the melting point of the resin and improving the moldability when producing a thermosetting resin from the thermosetting resin composition of the present embodiment. Since it is a cyanate ester, it has the characteristic that it is rich in the reactivity with the compound of said (1) and (2) which comprises this invention compared with another compound. The cyanate ester is not particularly limited as long as the melting point is not high, but those having a melting point of 120 ° C. or lower are preferable.
The cyanate ester has a structure in which cyanate (—OCN) and another hydrocarbon group are ester-bonded. In other words, a part of the hydrocarbon is substituted with cyanate. Although the said hydrocarbon group is not specifically limited, For example, it is preferable that they are the following phenyl derivatives and bisphenyl derivatives.
From the viewpoint of maintaining the heat resistance of the resin, the cyanate ester preferably has a structure of two or more cyanates in one molecule.
As said cyanate ester, the compound represented by following General formula (6) is mentioned as an example of a phenyl derivative, for example.

[Wherein X ⁵ represents an alkylene group having 1 to 10 carbon atoms, a group represented by the general formula (3), a group represented by the formula “—SO ₂ —” or “—CO—”, an oxygen atom] Or a single bond, and n is an integer of 0 to 20. ]

X ⁵ in the general formula (6), the same ones listed as X ¹ in the general formula (1), preferably a linear or branched alkylene group having 1 to 3 carbon atoms.

Specific examples of the compound represented by the general formula (6) include a phenol novolac type polyfunctional cyanate ester represented by the following formula (6-1).

[Wherein n is an integer of 0 to 20. ]

Further, in the compound represented by the general formula (6), when n is 0, examples of the bisphenyl derivative include a compound represented by the following general formula (5).

[Wherein X ³ represents an alkylene group having 1 to 10 carbon atoms, a group represented by the general formula (3), a group represented by the formula “—SO ₂ —” or “—CO—”, an oxygen atom] Or a single bond. ]

X ³ in the general formula (5), the same thing can be mentioned the X ⁵ in the general formula (6), preferably a linear or branched alkylene group having 1 to 3 carbon atoms.

Specific examples of the compound represented by the general formula (5) include a bisphenol A dicyanate represented by the following formula (5-1) or a bisphenol E dicyanate represented by the following formula (5-2). It is done.

　　　　　　　　　　　　　　　　　 

　　　　　　　　　　　　　　　　　 

In addition, as the cyanate ester used in this embodiment, bisphenol F type dicyanate, bisphenol M type dicyanate, bisphenol P type dicyanate, cresol novolac type cyanate, dicyclopentadiene novolac type cyanate, tetramethylbisphenol F type dicyanate, or biphenol diester Examples include cyanate.

As the cyanate ester used in this embodiment, one of those described above can be used alone, or two or more can be used in combination.

That is, in one embodiment of the thermosetting resin composition of the present invention, the cyanate ester is preferably a compound represented by the general formula (6), and is represented by the general formula (5). More preferably, it is a compound. In addition, the compound represented by the general formula (5) includes a compound in which X ³ in the general formula (5) is a linear or branched alkylene group having 1 to 3 carbon atoms, the general formula (5) It is preferably at least one compound selected from the group consisting of bisphenol A type cyanate represented by 5-1) and bisphenol E type dicyanate represented by general formula (5-2). More preferably, it is at least one compound selected from the group consisting of the compound represented by (5-1) and the compound represented by the general formula (5-2).

The content of the cyanate ester in the thermosetting resin composition of the present embodiment is not particularly limited as long as it is a content that improves moldability while maintaining the heat resistance and low thermal expansion coefficient of the resin. The amount is preferably 0.3 to 10 moles compared to the compound represented by the general formula (1). Further, the molar amount is more preferably 0.5 to 10 times. The molar amount is more preferably 1 to 5 times, and particularly preferably 1 to 3 times the molar amount. By being in this range, the effect of improving the moldability while maintaining the heat resistance and low thermal expansion coefficient of the resin can be obtained.

[Other ingredients]
The thermosetting resin composition of the present embodiment contains other components in addition to the compound represented by the general formula (1), the compound represented by the general formula (2), and the cyanate ester. be able to. Examples of other components include a curing accelerator.
As a hardening accelerator, it does not specifically limit and a well-known thing can be used. Specifically, a phosphine compound, a compound having a phosphonium salt, an aromatic amine compound, or the like can be given.
Examples of the phosphine compound include: alkylphosphine such as ethylphosphine or propylphosphine, primary phosphine such as phenylphosphine; dialkylphosphine such as dimethylphosphine or diethylphosphine; secondary phosphine such as diphenylphosphine, methylphenylphosphine or ethylphenylphosphine; A trialkylphosphine such as phosphine, triethylphosphine, tributylphosphine or trioctylphosphine; or tricyclohexylphosphine, triphenylphosphine, alkyldiphenylphosphine, dialkylphenylphosphine, tribenzylphosphine, tolylphosphine, tri-p-styrylphosphine, Tris (2,6-dimethoxyphenyl) phosphine, tris 4-methylphenyl phosphine, tertiary phosphines such as tri-4-methoxyphenyl phosphine or tri-2-cyanoethyl phosphine, and the like.
Examples of the compound having a phosphonium salt include a compound having a tetraphenylphosphonium salt, an alkyltriphenylphosphonium salt, or the like. Specifically, tetraphenylphosphonium thiocyanate, tetraphenylphosphonium tetra-p-methylphenylborate, butyltriphenyl Examples thereof include phenylphosphonium thiocyanate.
Examples of the aromatic amine compound include imidazoles, specifically, 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethylimidazole, 2,4-dimethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5 -Hydroxymethylimidazole, 1-vinyl-2-methylimidazole, 1-propyl-2-methylimidazole, 2-isopropylimidazole, 1-cyanomethyl-2-methyl-imidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole , 1-cyano Chill-2-undecyl imidazole, or 1-cyanoethyl-2-phenylimidazole, and the like.
These curing accelerators may be produced by a conventional method, or commercially available products may be used.
Moreover, a hardening accelerator may be used individually by 1 type, and may be used in combination of 2 or more type.
When a curing accelerator is blended in the thermosetting resin composition of the present embodiment, the blending amount of the curing accelerator is a compound represented by the general formula (1) and a compound represented by the general formula (2). Is preferably 0.1 to 5.0 parts by weight, more preferably 0.1 to 3.0 parts by weight, and more preferably 0.3 to 1 part by weight based on a total of 100 parts by weight of the above and the cyanate ester. Particularly preferred is 5 parts by mass.
However, although the thermosetting resin composition of the present embodiment can be sufficiently polymerized without using a curing accelerator, there is an advantage that polymerization can be performed in a particularly short time by using a curing accelerator.

The thermosetting resin composition of the present embodiment may further contain a solvent. Preferable examples of the solvent include organic acids, inorganic acids, or other organic solvents. Among these, an organic solvent is more preferable among them. Furthermore, for example, a dipolar solvent is particularly preferable because it is a solvent that becomes a homogeneous reaction system during the reaction. Specific examples of the solvent contained in the thermosetting resin composition include ketone organic solvents such as acetone or methyl ethyl ketone, amide organic solvents such as N-methylpyrrolidone, dimethylformamide, or dimethylacetamide, and sulfoxides such as dimethyl sulfoxide. Organic solvents or ether solvents such as dioxane are preferred.

[Thermosetting resin]
The thermosetting resin of the present embodiment includes the compound represented by the general formula (1) and the compound represented by the general formula (1) in an amount of 0.2 to 0.5 times the molar amount of the general formula (1). A mixture containing a compound represented by the formula (2), a cyanate ester, and other components as required is polymerized.
By setting the ratio of the molar amount of the compound represented by the general formula (1) and the compound represented by the general formula (2) within such a range, the Tg (glass transition point) of the thermosetting resin can be increased. Since it rises specifically, the heat resistance is markedly improved.

The method for polymerizing the thermosetting resin composition of the present embodiment is not particularly limited, and may be performed by a method such as heating the thermosetting resin composition or irradiating the thermosetting resin composition with ultraviolet rays. It can be carried out.
The heating temperature and heating time in the case of heating the thermosetting resin composition are not particularly limited, and are preferably determined as appropriate according to the blending of the thermosetting resin composition.
The heating temperature is preferably from 100 to 240 ° C, more preferably from 180 to 220 ° C. The heating time is preferably 0.5 to 12 hours, more preferably 1 to 10 hours, and particularly preferably 1 to 8 hours.

In addition, as the step of heating and curing the thermosetting resin composition, it is also preferable to heat the thermosetting resin composition while raising the temperature stepwise. That is, it is preferable that the process of hardening includes the process of the 2 or more steps from which the temperature conditions of heating temperature or heating time differs. Specifically, for example, a thermosetting resin composition heated at 120 to 180 ° C. for 1 to 6 hours, heated at 160 to 200 ° C. for 0 to 2 hours, and heated at 180 to 220 ° C. for 0.5 to 4 hours. The curing step is included.
In order to obtain a thermosetting resin having excellent mechanical properties, it is preferable that the heating temperature of the first stage is high or the heating time is long among the processes of the plurality of stages. More preferably, the heating temperature is high and the heating time is long.
Among them, the curing process of heating at 160 ° C. for 1 hour—180 ° C. for 1 hour at −220 ° C. for 4 hours, or the curing of the thermosetting resin composition of heating at 160 ° C. for 6 hours at −220 ° C. for 4 hours. A process is preferred. By curing under such conditions, a resin particularly excellent in bending strength can be obtained.

The thermosetting resin of the present embodiment preferably has a glass transition point (Tg) of 250 ° C. or higher. Here, the glass transition point is calculated by thermomechanical analysis (TMA). As an example of measurement, the glass transition point is heated for about 5 to 20 minutes at a rate of temperature increase of 3 to 10 ° C./min. Obtained from the slope of the TMA curve shown. The glass transition point is more preferably 250 to 350 ° C. as a guide. When the glass transition point is 250 ° C. or higher, that is, as high as the conventional thermosetting resin, the resin has high heat resistance.

The thermosetting resin of this embodiment preferably has a coefficient of thermal expansion (CTE) of 50 ppm or less. Here, the coefficient of thermal expansion is calculated by thermomechanical analysis (TMA), and as a measurement example, the same measurement as that of the glass transition point described above is performed, and can be calculated from the slope of the TMA curve. The thermal expansion coefficient is more preferably 20 to 45 ppm. When the coefficient of thermal expansion is sufficiently small, the volume change due to heat is small, cracks can be prevented, and the resin used as a material for a member used in a high heat environment, particularly a sealing material, is good.

[Use of thermosetting resin and / or thermosetting resin composition]
As a use of the thermosetting resin composition of the present embodiment, it can be used for sealing when insulating properties such as fields requiring high heat resistance and various power devices are required.
For example, as a preferable use of the thermosetting resin composition, it can be used as a raw material of a production method used in a production method of a sealing material that requires these insulating properties. In particular, it can be used as a raw material for a sealing material of a SiC semiconductor used in a high current power module. Specifically, for the thermosetting resin composition of the present invention, inorganic fillers such as various silicas, various aluminas, and titanium oxides, and additives for sealing materials such as the above-described curing accelerators depending on the case. Is preferably used as a sealing material.

The SiC semiconductor is a semiconductor using single crystal and high purity SiC, which replaces the Si semiconductor that is widely used at present, and its use and development are being promoted. A high current can be obtained and the semiconductor can be miniaturized, and the future is expected. Compared to the conventionally used Si semiconductor, it has a high capacity and high voltage, but generates a large amount of heat. For this reason, the SiC semiconductor encapsulant requires high heat resistance, a low coefficient of thermal expansion, crack resistance, and excellent moldability. The thermosetting resin and / or thermosetting resin composition of the present embodiment is particularly suitable as a sealing material for SiC semiconductors because high heat resistance, excellent moldability, and crack resistance are obtained.

As a further use of the thermosetting resin composition of the present embodiment, it has a high glass transition point (Tg) for a normal Si semiconductor substrate and more than 250 ° C., so that the heat generation is particularly high under a high current. It can be used as a sealing material in modules and devices for SiC semiconductors that are tolerated.

As a use of the thermosetting resin of this embodiment, it can be used as various materials in the field where high heat resistance is required.
For example, a thermosetting resin can also be used in the above-described method for manufacturing a sealing material that requires insulation, or can be used as a raw material for the manufacturing method. In this case, when the thermosetting resin is manufactured, the above-described additive for sealing material may be added to be used as a resin that can be used in the manufacturing method of the sealing material, or as a raw material of the sealing material. . For example, the resin composition is used as a raw material, and other components such as an inorganic filler, a curing agent, a curing accelerator and the like are appropriately mixed and used.

Hereinafter, the present embodiment will be described more specifically with reference to examples and comparative examples, but the present embodiment is not limited to the following examples.

[Examples 1 to 5, Comparative Example 1] (Differential scanning calorimetry)
The compound represented by the formula (1-1) (4,4′-diphenylmethane bismaleimide, hereinafter referred to as BMI), the compound represented by the formula (2-1) (3,3 ′-(methylene-1) , 4-diphenylene) bis (3,4-dihydro-2H-1,3-benzoxazine, hereinafter referred to as Pd-type benzoxazine) and bisphenol A-type dicyanate (hereinafter referred to as BAD) differential scanning calorimetry (DSC).
BMI, Pd-type benzoxazine, and BAD were mixed at a molar ratio shown in Table 1 and dissolved by adding methylene chloride to obtain a uniform solution. Then, deaeration treatment was performed in a 40 ° C. vacuum oven, and a differential scanning calorimeter (DSC-60, manufactured by Shimadzu Corporation) was used in a nitrogen atmosphere (20 mL / min) at a rate of temperature increase (10 ° C./min). An exothermic peak was observed to confirm the curing reaction characteristics. The results of differential scanning calorimetry are shown in FIG. In Table 1, Onset temperature indicates the polymerization initiation temperature, and Exothermal peak indicates an exothermic peak. In FIG. 1 and the specification, Pd-type benzoxazine may be expressed as Pd.

　　　　　　　　　　　　　　　　　 

As shown in FIG. 1, it was confirmed that the exothermic peak shifts to the low temperature side by containing BAD. The melting point in Comparative Example 1 not containing BAD is about 150 ° C., whereas the melting point in Examples 1 to 5 not containing BAD is about 60 ° C. It was confirmed that the thermosetting resins of Examples 1 to 5 were excellent in moldability.

(Fourier transform infrared spectroscopy (FT-IR) measurement)
The curing conditions of 180 ° C. for 4 hours, 200 ° C. for 4 hours, and 220 ° C. for 4 hours, and the reaction investigation by FT-IR before curing were compared with those of Pd-type benzoxazine + BMI + BAD (0.3: 1: 2). Performed on mixed system. The results are shown in FIGS. FIG. 3 is an enlarged view at 1116.1 to 959.1 cm ⁻¹ in FIG.

As shown in FIG. 2, the OCN group peak (2275 cm ⁻¹ ) derived from the BAD monomer was not observed by heating at 180 ° C. for 4 hours, and as shown in FIG. 3, the Pd monomer was heated by heating at 180 ° C. for 4 hours. The derived oxazine ring peak (1034 cm ⁻¹ ) was not observed. From this, it was confirmed that the BAD monomer and the Pd monomer are almost consumed in the polymerization reaction.
In addition, since a succinimide peak (1176 cm ⁻¹ ) derived from the BMI polymer and a triazine ring peak (1564 cm ⁻¹ ) derived from the BAD polymer were observed, it was confirmed that the polymerization reaction was proceeding.

[Examples 6 to 13, Comparative Examples 2 to 3]
Pd-type benzoxazine (Pd), BMI, and BAD were mixed at a molar ratio shown in Table 2, heated and polymerized to prepare a thermosetting resin. Specifically, first, Pd, BMI, and BAD were placed in a standard bottle so that the total was 14 g, and melt-mixed while stirring in a 120 ° C. oil bath. Subsequently, it poured into the Al casting plate previously heated at 120 degreeC, and after deaeration, the resin was hardened by heating at 200 degreeC for 4 hours. All of the obtained cured products were dark red and transparent.

(Glass transition point / thermal expansion coefficient)
Using the thermosetting resin obtained above, thermomechanical analysis (TMA) was performed, and the glass transition point (Tg) and the coefficient of thermal expansion (CTE) were examined.
Specifically, measurement was performed using a TMA-60 (trade name) manufactured by Shimadzu Corporation at a heating rate of 5 ° C./min, a compression method, a load of 5 g, and air of 100 ml / min. The test piece of the sample thermosetting resin was measured after polishing to 5 (length) × 5 (width) × 10 (height) mm after heating for 10 minutes at the final curing temperature to remove strain. From the slope of the TMA curve, Tg (° C.) and CTE (ppm) at 50 to 100 ° C. were calculated. The results are shown in Table 2. In addition, the measurement conditions of the glass transition point and the thermal expansion coefficient in the following examples are the same as those in the above examples and comparative examples.

(Raw material mass reduction temperature, residue amount)
Thermogravimetry (TGA) was performed using the thermosetting resin obtained as described above, and the temperature at which the raw material mass decreased and the amount of residue were examined.
Specifically, using a TGA-50 (trade name) manufactured by Shimadzu Corporation, measurement was performed at a temperature rising rate of 5 ° C./min and nitrogen of 20 ml / min, and the mass was 5% based on the mass at 40 ° C. The temperature when the amount was reduced was Td ₅ , and the temperature when the amount was reduced by 10% was Td ₁₀ . The results are shown in Table 2.
Moreover, the amount of residue (mass%) at the time of heating to 800 degreeC was calculated | required on the basis of the mass at the time of 40 degreeC, and chemical heat resistance was evaluated. The results are shown in Table 2. In addition, the measurement conditions of the raw material mass decreasing temperature and the amount of residue in the following examples are the same.

　　　　　　　　　　　　　　　　　 

From the above results, the thermosetting resins of Examples 6 to 13 according to the present embodiment have a Tg of 250 ° C. or higher and excellent moldability as compared with Comparative Examples 2 to 3. In addition, it was confirmed that it has excellent heat resistance. Further, the thermosetting resins of Examples 6 to 13 have a low coefficient of thermal expansion (CTE) compared to 70 ppm / ° C. of general-purpose epoxy resins, and are excellent in low thermal expansion coefficient. confirmed.
Further, the thermosetting resins of Examples 6 to 13 showed high values of T _d5 and T _d10 , and it was found that these resins were excellent in both physical and chemical heat resistance.

[Examples 14 to 16]
Pd-type benzoxazine (Pd), BMI, and BAD were mixed at a molar ratio of 0.3: 1: 2.0, and a resin was produced under the curing conditions shown in Table 3. Specifically, first, Pd, BMI, and BAD were measured so that the whole was 25 g, and BMI and BAD were first taken into a standard bottle, and melt-mixed while stirring in an oil bath at 150 ° C. . Thereafter, the temperature was lowered to 120 ° C., Pd was added, stirred, poured into an Al casting plate preheated to 120 ° C., degassed, and thermally cured under the curing conditions of stepwise curing shown in Table 3. The functional resin was cured. For example, Example 14 shows curing conditions for curing a resin by heating at 120 ° C. for 6 hours and then heating at 220 ° C. for 4 hours. Table 3 shows the thermal characteristics and mechanical characteristics of the obtained cured product.

　　　　　　　　　　　　　　　　　 

As shown in Table 3, the thermosetting resins of Examples 14 to 16 exhibited thermal properties of Tg 250 ° C. or higher and CTE 50 ppm / ° C. or lower, and mechanical properties of bending strength 150 MPa or higher.
Among Examples 14 to 16, it was confirmed that the thermosetting resin of Example 16 cured by performing the first stage curing at a high temperature was particularly excellent in mechanical properties. Further, the thermosetting resin obtained under the curing conditions in which the resin was cured by heating at 160 ° C. for 6 hours and then at 220 ° C. for 4 hours also showed the same mechanical characteristics as in Example 16.
Therefore, it was confirmed that a thermosetting resin having excellent mechanical properties can be obtained by curing the first stage at a high temperature for a long time.

[Examples 17 to 18]
Pd-type benzoxazine (Pd), BMI, and BAD or bisphenol E-type dicyanate (hereinafter also referred to as BED) are mixed at a molar ratio shown in Table 4, and heated and polymerized to produce a thermosetting resin. did. Specifically, first, Pd, BMI, and BAD or BED were placed in a standard bottle so that the total was 14 g, and melt-mixed while stirring in a 120 ° C. oil bath. Subsequently, it poured into the Al casting plate preheated to 120 degreeC, and after deaeration, the resin was hardened by heating at 220 degreeC for 4 hours. All of the obtained cured products were dark red and transparent.

The glass transition point, the thermal expansion coefficient, the raw material mass reduction temperature, and the amount of residue of the obtained cured product were measured by the same method as described above. The results are shown in Table 4.

　　　　　　　　　　　　　　　　　 
 

From the above results, the thermosetting resin of Example 18 using BED instead of BAD shows comparable values in Tg and CTE compared to the thermosetting resin of Example 17 using BAD. It was confirmed.
Furthermore, similarly to the thermosetting resin of Example 17, the thermosetting resin of Example 18 shows high values of T _d5 and T _d10 , and these resins are excellent in both physical and chemical heat resistance. Things turned out.
From these facts, it was confirmed that a thermosetting resin excellent in heat resistance and a low thermal expansion coefficient can be obtained even if BED is used instead of BAD as the cyanate ester.

[Example 19]
Pd-type benzoxazine (Pd), BMI, and novolak-type cyanate ester (manufactured by Lonza; Primaset PT-30, phenol novolac-type cyanate ester, average functional group number 7.3; hereinafter also referred to as NCY). , 0.5: 1: 2.0, and the mixture was heated and polymerized to prepare a thermosetting resin. Specifically, Pd, BMI, and NCY were measured so that the whole became 25 g, and BMI and NCY were first taken in a standard bottle and melt-mixed while stirring in a 150 ° C. oil bath. Thereafter, the temperature is lowered to 120 ° C., Pd is added, and the mixture is stirred. Then, the mixture is poured into an Al casting plate preheated to 120 ° C. After degassing, 160 ° C. for 1 hour—180 ° C. for 1 hour—220 ° C. for 4 hours. The resin was cured by heating. All of the obtained cured products were dark red and transparent.

The glass transition point, the thermal expansion coefficient, the raw material mass reduction temperature, and the amount of residue of the obtained cured product were measured by the same method as described above. The results are shown in Table 5.

　　　　　　　　　　　　　　　　　 

From the above results, it was confirmed that the thermosetting resin of Example 19 using NCY instead of BAD showed similar values in Tg and CTE as in the case of using BAD.
Further, the thermosetting resin of Example 19 showed high values of T _d5 and T _d10 as in the case of using BAD, and it was found that this resin is excellent in both physical and chemical heat resistance. .
From these facts, it was confirmed that a thermosetting resin excellent in heat resistance and low thermal expansion coefficient can be obtained even when NCY is used instead of BAD as the cyanate ester.

[Example 20]
Pd-type benzoxazine (Pd), BMI, and NCY were mixed at a molar ratio of 0.3: 1: 2.0, and heated and polymerized to prepare a thermosetting resin. Specifically, Pd, BMI, and NCY were measured so that the whole became 25 g, and BMI and NCY were first taken in a standard bottle and melt-mixed while stirring in a 150 ° C. oil bath. Thereafter, the temperature is lowered to 120 ° C., Pd is added, and the mixture is stirred. Then, the mixture is poured into an Al casting plate preheated to 120 ° C. After degassing, 160 ° C. for 1 hour—180 ° C. for 1 hour—220 ° C. for 4 hours. The resin was cured by heating. All of the obtained cured products were dark red and transparent. The results are shown in Table 6.

[Example 21]
Pd-type benzoxazine (Pd), BMI, and cyanate ester were mixed at a molar ratio of 0.3: 1: 2.0, and heated and polymerized to prepare a thermosetting resin. Specifically, Pd, BMI, and cyanate ester are measured so that the total weight is 25 g. First, BMI and cyanate ester are placed in a standard bottle, and the mixture is melt-mixed while stirring in an oil bath at 150 ° C. went. The measured cyanate ester is a mixture of BAD and NCY at a molar ratio of 1: 1.
Thereafter, the temperature is lowered to 120 ° C., Pd is added, and the mixture is stirred. Then, the mixture is poured into an Al casting plate preheated to 120 ° C. After degassing, 160 ° C. for 1 hour—180 ° C. for 1 hour—220 ° C. for 4 hours. The resin was cured by heating. All of the obtained cured products were dark red and transparent. The results are shown in Table 6.

　　　　　　　　　　　　　　　　　 

As shown in Table 6, the thermosetting resin of Example 20 prepared by mixing Pd-type benzoxazine (Pd), BMI, and NCY at a molar ratio of 0.3: 1: 2.0 was CTE 50 ppm. It was less than / ° C. and Tg was higher than 350 ° C., indicating excellent thermal characteristics.
Further, in place of NCY, the thermosetting resin of Example 21 using a cyanate ester in which BAD and NCY were mixed at a molar ratio of 1: 1 is similar to the case of using NCY alone as the cyanate ester. It was confirmed that Tg and CTE exhibit excellent thermal properties.
From this, it was confirmed that even when a mixture of BAD and NCY was used as the cyanate ester, a thermosetting resin excellent in heat resistance and low thermal expansion coefficient was obtained.

Since the thermosetting resin of the present invention is excellent in heat resistance, low thermal expansion coefficient, and moldability, it is suitably used for power devices for electric vehicles and hybrid vehicles. According to the thermosetting resin composition of the present invention, it is possible to provide a thermosetting resin excellent in heat resistance, a low coefficient of thermal expansion, and moldability.

Claims (7)

1. A compound represented by the following general formula (1) and a compound represented by the following general formula (2) in an amount of 0.2 to 0.5 times the molar amount of the compound represented by the following general formula (1): And a thermosetting resin obtained by polymerizing a mixture containing cyanate ester.
   

   

   
   [Wherein, X ¹ and X ² are each independently an alkylene group having 1 to 10 carbon atoms, a group represented by the following general formula (3), a formula “—SO ₂ —” or “—CO—” Or a single bond. ]
   

   

   
   [Wherein Y is a hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring, and n is an integer of 1 or more. ]
2. X ¹ and X ² are each independently a linear or branched alkylene group having 1 to 3 carbon atoms, or a group represented by any of the following formulas (i) to (iii): 1. The thermosetting resin according to 1.
   

   
3. The thermosetting resin according to any one of claims 1 to 3, wherein the mixture contains 0.3 to 10 times the molar amount of the cyanate ester relative to the compound represented by the general formula (1). .
4. A compound represented by the following general formula (1) and a compound represented by the following general formula (2) in an amount of 0.2 to 0.5 times the molar amount of the compound represented by the general formula (1): And a thermosetting resin composition comprising a cyanate ester.
   

   

   
   [Wherein, X ¹ and X ² are each independently an alkylene group having 1 to 10 carbon atoms, a group represented by the following general formula (3), a formula “—SO ₂ —” or “—CO—” Or a single bond. ]
   

   

   
   [Wherein Y is a hydrocarbon group having 6 to 30 carbon atoms having an aromatic ring, and n is an integer of 1 or more. ]
5. The X ¹ and X ² are each a linear or branched alkylene group having 1 to 3 carbon atoms, or a group represented by any of the following formulas (i) to (iii): The thermosetting resin composition as described.
   

   

   
   
6. The thermosetting resin composition according to claim 4 or 5, wherein the mixture contains 0.3 to 10 times the molar amount of the cyanate ester relative to the compound represented by the general formula (1).
7. A sealing material for SiC semiconductor containing the thermosetting resin composition according to any one of claims 4 to 6.

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