JP6509009B2 - Bismaleimide compound, composition containing the same, and cured product - Google Patents

Description

  The present invention relates to a novel bismaleimide compound, a curable imide composition, and a cured imide product. A bismaleimide compound can give a material excellent in heat resistance and flame retardance by being crosslinked alone or reacted with various maleimide compounds or crosslinking agents, and a sealing material, a substrate material, an insulating material It can be used for various applications. Particularly, high heat resistant substrate material, flexible substrate material, high heat resistant low dielectric material, high heat resistant CFRP material (carbon fiber composite material), high heat resistance for automotive SiC power devices, which requires extremely high heat resistance and moldability to be compatible. It can be used for sealing material applications.

The heat-resistant resin has heat resistance, which is a disadvantage of organic materials compared to inorganic materials, and also has excellent processability, so it is widely used in the fields of sealing materials, substrate materials, insulating materials, etc. It has been
However, new materials that require extremely high heat resistance, such as flexible substrate materials for high-temperature processes, high-temperature high-frequency heat-resistant substrate materials, high-heat-resistant CFRP materials, and automotive SiC power device sealing materials, are emerging. . For example, in a SiC power device, operation in a high temperature region at 250 ° C. or higher is assumed, but in a sealing material using a conventional heat resistant resin, operation at 200 ° C. is limited because the heat resistance is not sufficient. Met. Therefore, a sealing material that can withstand operation at 250 ° C. is desired. That is, with conventional heat-resistant resins, application to new materials such as sealing materials for SiC power devices for vehicles has become difficult.

  As conventional heat resistant resins, those obtained by increasing the heat resistance of epoxy resins having excellent moldability have been mainly used. For example, an epoxy resin composition containing a phenol resin, an epoxy resin composition containing benzoxazine, an amine resin or a cyanate resin, and an epoxy resin composition containing a maleimide resin can be mentioned. Other examples include polyimide resins and the like. However, with these conventional resins, it is difficult to simultaneously achieve the above-mentioned extremely high heat resistance and moldability. Moreover, while the glass transition temperature (Tg) was high, the thermal decomposition start temperature was inadequate.

For example, in the case of epoxy resin, introduction of polycyclic aromatic group (patent document 1), introduction of hetero group (patent document 2), improvement of crosslink density (patent document 3), etc. have been studied as methods for increasing heat resistance. The Although these are effective for improving the glass transition temperature and the dimensional stability, there is a limit to the improvement of the thermal decomposition initiation temperature.
Although the thing which mix | blended maleimide resin with the epoxy resin composition (patent document 4) has improved thermal decomposition start temperature, it is inadequate for long-term heat resistance of 250 degreeC, and a moldability becomes a subject.
An epoxy resin mixed with an amine resin (Patent Document 5) or a benzoxazine resin (Patent Document 6) improves the glass transition temperature (Tg) but has a thermal decomposition initiation temperature lower than that of the epoxy resin, and Cured products have the disadvantage of being brittle.
The epoxy composition containing a cyanate resin (Patent Document 7) has a problem in that the temperature control at the time of curing is difficult, there is a problem in moldability, and it becomes expensive.
The polyimide resin is excellent in the thermal decomposition initiation temperature, but it is difficult to form a thick film, and its application to a molding material such as a sealing material is difficult.

JP 2001-261785 A JP-A-2-157264 JP-A-63-264622 Japanese Patent Application Laid-Open No. 60-23424 Japanese Patent Application Laid-Open No. 56-115314 Japanese Patent Application Publication No. 2003-64155 Japanese Patent Application Publication No. 2003-261743

  An object of the present invention is to provide a material in which extremely high heat resistance, which is difficult in conventional heat resistant resins, and moldability comparable to epoxy resins are compatible.

  The inventors of the present invention have found that a specific imide compound is expected to solve the above-mentioned problems, and that it is compatible with extremely high heat resistance and thermoformability by intensive studies.

式中、Ｒ^１及びＲ^２は、それぞれ独立して、置換または無置換のアルキル基を表す。Ｍ^１、Ｍ^２、Ｍ^３及びＭ^４は、それぞれ独立して、水素原子または置換もしくは無置換のアルキル基を表す。 That is, the present invention relates to a bismaleimide compound represented by the following general formula (1).

In formula, R < ¹ > and R < ² > respectively independently represent a substituted or unsubstituted alkyl group. M ¹ , M ² , M ³ and M ⁴ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group.

式中、Ｑはｍ価の有機基を表し、Ｍ^５及びＭ^６は、それぞれ独立して、水素原子または置換もしくは無置換のアルキル基を表し、ｍは１〜１０の整数を表す。 Further, the present invention relates to an imide composition comprising the above-described bismaleimide compound and a maleimide compound represented by the following general formula (2).

In the formula, Q represents an m-valent organic group, M ⁵ and M ⁶ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group, and m represents an integer of 1 to 10.

  Furthermore, the present invention relates to a curable imide composition comprising the above-mentioned bismaleimide compound and a crosslinking agent, or a curable imide composition obtained by further blending a crosslinking agent into the above-mentioned imide composition. . The present invention also relates to an imide cured product obtained by crosslinking and curing these curable imide compositions. This imide cured product is suitable for electronic materials.

  The bismaleimide compound of the present invention has heat resistance exceeding that of the epoxy resin, and has the same formability as the epoxy resin. Furthermore, it also has properties of low linear expansion coefficient and high Tg. Therefore, it can be suitably used as a material having extremely high heat resistance, such as a high heat resistant substrate material, a high temperature process flexible substrate material, a high heat resistant CFRP material, and a sealing material for automotive SiC power devices. Moreover, high durability more than conventional heat resistant resins can be imparted to sealing materials, substrate materials, insulating materials, etc., which can be applied using conventional heat resistant resins.

It is a < ¹ > H-NMR spectrum of the bismaleimide compound of this invention.

First, the bismaleimide compound of the present invention will be described.
The bismaleimide compound of the present invention is represented by the above general formula (1).

Here, R ¹ and R ² each independently represent a substituted or unsubstituted alkyl group. In the case of a substituted alkyl group, the substituent is not particularly limited, and examples thereof include an aryl group, an aralkyl group, an amino group, an alkoxy group, a hydroxyl group, a carboxyl group, a vinyl group and a halogen group. More preferably, it is an unsubstituted or phenyl group- or halogen-substituted alkyl group. More preferably, it is an unsubstituted or fluorine-substituted alkyl group.

  The substituted or unsubstituted alkyl group may have any of a linear structure, a branched structure, and a cyclic structure. Preferably it is a C1-C6 alkyl group, More preferably, it is C1-C3, More preferably, it is C1.

M ¹ , M ² , M ³ and M ⁴ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. In the case of a substituted alkyl group, the substituent is not particularly limited, and examples thereof include an aryl group, an aralkyl group, an amino group, an alkoxy group, a hydroxyl group, a carboxyl group, a vinyl group and a halogen group. More preferably, it is a hydrogen atom or an unsubstituted alkyl group. More preferably, at least one of M ¹ , M ² , M ³ and M ⁴ is an unsubstituted alkyl group.

The substituted or unsubstituted alkyl group in M ^{1 to} M ⁴ may be any of linear structure, branched structure and cyclic structure. More preferably, it is a C1-C6 alkyl group, more preferably, it is C1-C3 and still more preferably a C1 alkyl group.

The bismaleimide compound represented by the above general formula (1) may be a mixture of bismaleimide compounds different in the above R ¹ , R ² , M ¹ , M ² , M ³ and M ⁴ .

  Preferred specific examples of the bismaleimide compound represented by the above general formula (1) are shown in Table 1.

  In addition, the bismaleimide compound represented by the above general formula (1) may be an imide composition containing the maleimide compound represented by the above general formula (2) (hereinafter referred to as "other maleimide compound"). it can.

In the general formula (2), Q represents an m-valent organic group. m is an integer of 1 to 10, preferably 2 to 8.
The structure of Q is not limited, but in the case of a divalent organic group, structures of the following formulas (3) to (7) are preferably mentioned. Here, in the following formulas (3) to (7), * is a bonding site to each of two nitrogen atoms in the above general formula (2). Z ¹ and ^{Z 2} each independently represent a hydrogen atom, an alkyl group of C1 -C6, or a halogen-substituted alkyl group of C1 -C6. In Formula (3) to ^(7), the substitution position of Z 1, ^{Z 2} and the binding sites * are exemplary, but are not limited thereto.

M ⁵ and M ⁶ each independently represent a substituted or unsubstituted alkyl group or a hydrogen atom. In the case of a substituted alkyl group, the substituent is not particularly limited, and examples thereof include an aryl group, an aralkyl group, an amino group, an alkoxy group, a hydroxyl group, a carboxyl group, a vinyl group and a halogen group. More preferably, it is an unsubstituted alkyl group or a hydrogen atom.

The alkyl group in M ⁵ and M ⁶ may be any of linear structure, branched structure and cyclic structure. More preferably, it is a C1-C6 alkyl group, more preferably C1-C3 and still more preferably C1.

  A curable imide composition can be obtained by adding a crosslinking agent to the bismaleimide compound of the present invention. Similarly, the above imide composition containing another maleimide compound can be made a curable imide composition by blending a crosslinking agent.

  Here, as the crosslinking agent, known crosslinking agents can be used, and examples thereof include phenol resin, epoxy resin, cyanate resin, amino resin, benzoxazine resin. An active group (phenolic hydroxyl group, epoxy group, cyanate group, amino group, or phenolic hydroxyl group formed by ring-opening of an alicyclic moiety of benzoxazine) possessed by these crosslinking agents forms a maleimide group on carbon-carbon In addition to crosslinking by addition reaction with heavy bonds, the two carbon-carbon double bonds possessed by the bismaleimide compound of the present invention are polymerized and crosslinked.

  A well-known thing can be used as a phenol resin. For example, as phenols, in addition to phenols, cresols, alkylphenols such as xylenols, polyhydric phenols such as hydroquinone, naphthols, polycyclic phenols such as naphthalenediols, bisphenols such as bisphenol A and bisphenol F And polyfunctional phenol compounds such as phenol novolak and phenol aralkyl resin. Preferably, from the viewpoint of heat resistance and moldability, aralkyl type phenolic resins are desirable.

  As an epoxy resin, a well-known thing can be used and it selects from what has 2 or more of epoxy groups in 1 molecule. For example, bisphenol A, bisphenol F, 3,3 ', 5,5'-tetramethyl-bisphenol F, bisphenol S, fluorene bisphenol, 2,2'-biphenol, 3,3', 5,5'-tetramethyl-4 Epoxides of dihydric phenols such as 4,4′-dihydroxybiphenol, resorcin and naphthalenediols, tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, Epoxides of trivalent or higher phenols such as phenol novolac and o-cresol novolac, epoxidates of co-condensed resin of dicyclopentadiene and phenols, phenol aralkyl resins synthesized from phenols and paraxylylene dichloride, etc. Epoxides, phenols and bis The epoxy compound of a biphenylaralkyl type phenol resin synthesized from chloromethylbiphenyl etc., the epoxy compound of a naphthol aralkyl resin synthesized from naphthols and paraxylylene dichloride, etc. may be mentioned. These epoxy resins may be used alone or in combination of two or more. From the viewpoint of heat resistance and moldability, epoxy resins which are solid at normal temperature, such as epoxy resins obtained from phenol aralkyl resins and biphenyl aralkyl resins are preferable.

  As cyanate resin, bisphenol type cyanate resin, naphthol type cyanate resin, etc. are mentioned.

  As amino resins, aromatic amines such as 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylsulfone, m-phenylenediamine, p-xylylenediamine, etc., ethylenediamine, Aliphatic amines such as hexamethylene diamine, diethylene triamine, triethylene tetramine and the like can be mentioned.

  Examples of benzoxazine resins include P-d-type benzoxazines obtained from difunctional diamines and monofunctional phenols, and Fa-type benzooxazines obtained from monofunctional diamines and difunctional phenols. .

  In the curable imide composition, an accelerator which accelerates the addition reaction can be used, if necessary. Examples include amines, imidazoles, organic phosphines, Lewis acids, etc. Specifically, 1,8-diazabicyclo (5,4,0) undecen-7, triethylenediamine, benzyldimethylamine, tribasic Ethanolamine, dimethylaminoethanol, tertiary amines such as tris (dimethylaminomethyl) phenol, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2- Imidazoles such as heptadecyl imidazole, organic phosphines such as tributyl phosphine, methyl diphenyl phosphine, triphenyl phosphine, diphenyl phosphine, phenyl phosphine, etc., tetraphenyl phosphonium tetraphenyl borate, tetrafe Tetra-substituted phosphonium tetra-substituted borate such as tetraphosphorous phosphonium ethyltriphenyl borate and tetrabutyl phosphonium tetrabutyl borate tetraphenyl such as 2-ethyl-4-methylimidazole tetraphenyl borate and N-methylmorpholine tetraphenyl borate There is a boron salt etc. The addition amount is usually in the range of 0.1 to 5 parts by weight with respect to 100 parts by weight of the bismaleimide compound in the composition.

  Moreover, additives, such as an inorganic filler, a pigment, a flame retardant, a thixotropic agent, a coupling agent, and a fluidity improver, can be mix | blended with the curable imide composition of this invention. Examples of the inorganic filler include spherical or crushed fused silica, silica powder such as crystalline silica, alumina powder, glass powder, mica, talc, calcium carbonate, alumina, hydrated alumina, etc. The preferable blending amount in the case of using as a stopper is 70% by weight or more, more preferably 80% by weight or more.

  Examples of the pigment include organic or inorganic extender pigments and scale-like pigments. Examples of the thixotropic agent include silicones, castor oils, aliphatic amide waxes, oxidized polyethylene waxes, organic bentonites, and the like.

  In addition, the bismaleimide compound of the present invention can be crosslinked or cured by a known method by itself or by using the above-described curable imide composition to obtain the cured imide of the present invention. As a crosslinking method, thermosetting and photocuring may be mentioned.

  The imide cured product of the present invention has heat resistance exceeding that of the epoxy resin, and has the same formability as the epoxy resin. For example, 5 wt% weight loss is 400 ° C. or more, and transfer molding is possible at 200 ° C. or less. Furthermore, it has properties such as dimensional stability and flame retardancy. Therefore, it can be suitably used for electronic materials such as low dielectric materials, transparent heat resistant substrate materials, high heat resistant sealing materials, and high heat resistant substrate materials. In particular, it can be suitably used as an electronic material having extremely high heat resistance, such as a flexible substrate material compatible with high temperature processes, a high heat resistant substrate material compatible with high speed and high frequency, a high heat resistant CFRP material, and a sealing material for SiC power devices for vehicles. Moreover, high durability more than the conventional heat resistant resin can be provided also to the sealing material, the board | substrate material, and the insulation material which can be applied with the conventional heat resistant resin.

  An example of the method for producing the imide compound of the present invention will be described below.

  The imide compound (c-1) of the present invention is, for example, as shown in the following reaction formula (8), a biphenyl type diamine compound (a-1) and a maleic anhydride derivative (b-1), (b-2) Can be produced by reacting

Furthermore, when one type of maleic anhydride derivative is used, an imide compound (c-2) is obtained as shown in the following reaction formula (9).

In addition, during this reaction, a reaction as shown in Formula (10) partially occurs to obtain an oligomer component (d-1). The oligomer component may be contained in the resin because it has the effect of improving the toughness of the resin, but it may be removed by reprecipitation. From the viewpoint of improving the thermal decomposition stability, it is desirable that the amount of this oligomer component is small.

  Hereinafter, the embodiments of the present invention will be described in more detail using Examples and Comparative Examples, but the technical scope of the present invention is not limited to only the following embodiments. In addition, "%" shows a weight standard.

Example 1
In a separable flask, 50 g (0.234 mol) of 2,2'-dimethylbiphenyl-4,4'-diamine (m-TB, manufactured by Wakayama Seika Kogyo Co., Ltd.), 71 g (1.18 mol) of acetic acid, toluene The mixture was heated to 50.degree. C. and dissolved while introducing nitrogen. 52.8 g (0.472 mol) of citraconic anhydride was dropped, and the system was gradually heated while removing generated water out of the system, and reaction was performed under reflux for 1 hour. The reaction product was purified by reprecipitation to obtain 90 g of bismaleimide compound (e-1) as white crystals. 96% yield. The amine equivalent was over 100,000, and it was confirmed that almost all the amino groups had reacted. The melting point of the product was 142 ° C.

Example 2
In the same manner as in Example 1, except that 45.9 g of maleic anhydride was added instead of citraconic anhydride, 60 g of bismaleimide compound (e-2) as pale yellow crystals was obtained. 69% yield. Amine equivalent is over 100,000.

Example 3
A bismaleimide compound (e-3) was obtained in the same manner as in Example 1 except that 29.5 g of 2,3-dimethylmaleic anhydride and 23.9 g of maleic anhydride were added instead of citraconic anhydride. ) Was obtained. 89% yield. Amine equivalent is over 100,000.

Example 4
In the same manner as in Example 1, bismaleimide compound (white crystal) was used in the same manner as in Example 1 except that 74.9 g of 2,2′-bis (trifluoromethyl) biphenyl-4,4′-diamine was used instead of m-TB. Obtained 97 g of e-5). 82% yield. Amine equivalent is over 100,000.

Example 5
Instead of m-TB, 74.9 g of 2,2'-bis (trifluoromethyl) biphenyl-4,4'-diamine was used, and 45.9 g of maleic anhydride was added instead of citraconic anhydride, In the same manner as in Example 1, 94 g of bismaleimide compound (e-6) as pale yellow crystals was obtained. 84% yield. Amine equivalent is over 100,000.

Comparative Example 1
In the same manner as in Example 1 except that 50 g of 4,4′-diaminodicyclohexylmethane was added instead of m-TB, 90 g of a bismaleimide compound (f-1) as white crystals was obtained. 95% yield. The amine equivalent was over 100,000 and melting point 189 ° C.

Comparative example 2
In the same manner as in Comparative Example 1 except that 46.5 g of maleic anhydride was added instead of citraconic anhydride, 81 g of bismaleimide compound (f-2) as white crystals was obtained. 93% yield. The amine equivalent was over 100,000 and melting point 189 ° C.

Examples 6 to 12 and Comparative Examples 3 to 7
As a bismaleimide compound, e-1, e-2, e-5, e-6, f-1 or f-2 obtained in the above examples and comparative examples were used. Further, as other maleimide compounds, N, N′-diphenylmethane bismaleimide (BMI; manufactured by Daiwa Kasei Kogyo Co., Ltd.) and phenylmethane maleimide oligomer (BMI oligomer; BMI-3200, m = 8, manufactured by Daiwa Kasei Kogyo Co., Ltd.) were used. Further, as a crosslinking agent, o-cresol novolac type epoxy resin (OCNE; epoxy equivalent 200, softening point 65 ° C.), phenol aralkyl resin (PA; Mitsui Chemicals, Inc., MILEX XLC-4L, OH equivalent 168, softening point 61 C), 4,4'-diaminodiphenyl ether (DPE; made by Wakayama Seika Kogyo Co., Ltd.), benzoxazine (BF-BXZ; made by Konishi Chemical Industry Co., Ltd.) and using triphenylphosphine as a resin component as an accelerator On the other hand, 1 part by weight was blended and kneaded to obtain a resin composition. The resin composition was molded at 175 ° C., post cured at 200 ° C. for 4 hours, post cured for 4 hours to obtain a cured test piece, and then used for various physical property measurements.

The heat stability test and transfer moldability evaluation were implemented about the cured | curing material test piece obtained by the above Example and the comparative example.
The heat resistance evaluation is performed under the conditions of a temperature rising rate of 10 ° C./min under a nitrogen stream of 200 mL / min using a differential thermal thermal gravimetry simultaneous measuring apparatus (apparatus name: TG / DTA7300 manufactured by SII Nano Technology). The 5% weight loss temperature (T _d ⁵ ) and the weight loss at 600 ° C. (residual carbon percentage) were measured.
The glass transition temperature (Tg) and the coefficient of linear expansion (CTE) were measured at 5 ° C. under a nitrogen stream of 200 mL / min using a thermomechanical measuring device (device name: TM / SS7100 manufactured by SII Nano Technology). It calculated | required by the temperature increase rate of min. Tg was determined from the inflection point at which the linear expansion coefficient changes. CTE was computed from the dimensional change of the test piece in 40-60 degreeC.
When a bending test piece was produced by a transfer molding machine, the formability was evaluated as ○ when a uniform test piece without blisters and cracks was obtained, and as × when not.
The results obtained by these measurements are shown in Table 2. The ratio of the formulation is the molar ratio.

Claims (6)

The bismaleimide compound represented by following General formula (1).

In the formula, ^{R 1} and ^{R 2} each independently represents an alkyl group of C1 to C3. M ¹ and M ² each represent a hydrogen atom, and M ³ and M ⁴ each independently represent a C1-C3 alkyl group .
An imide composition comprising the bismaleimide compound according to claim 1 and a maleimide compound represented by the following general formula (2).

In the formula, Q is a divalent group represented by any of the following formulas (3) to (7), and M ⁵ and M ⁶ are each independently a hydrogen atom or a substituted or unsubstituted alkyl Represents a group, and m represents an integer of 1 to 10.

In formulas (3) to (7), * is a bonding site to each of two nitrogen atoms in general formula (2), and Z ¹ and Z ² are each independently a hydrogen atom, C 1 to C 6 It represents an alkyl group or a C1-C6 halogen-substituted alkyl group.

  A curable imide composition comprising the bismaleimide compound according to claim 1 and a crosslinking agent.   A curable imide composition obtained by further blending a crosslinking agent into the imide composition according to claim 2.   An imide cured product obtained by crosslinking and curing the curable imide composition according to claim 3 or 4.   The cured imide according to claim 5, which is for electronic materials.

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