Bismaleimide compounds, curable compositions, and cured products

Abstract

The present invention provides a bismaleimide compound that does not significantly degrade the mechanical properties of the resulting cured product even when the filler content in the curable composition is high, a curable composition containing the same, and a cured product. [Solution] The bismaleimide compound of the present invention has a structure represented by general formula (I). TIFF2026145044000010.tif54161 (In the formula, R 1 X is an alkylene chain or alkenylene chain having 12 to 24 carbon atoms, having at least one substituent selected from the group consisting of alkyl groups having 1 to 4 carbon atoms and alkenyl groups having 2 to 4 carbon atoms. 1 ~X 4 These are, independently, hydrogen, a methyl group, or a halogen.

Description

[Technical Field]

[0001] The present invention relates to a novel bismaleimide compound, a curable composition containing the bismaleimide compound, and a cured product obtained from the curable composition. [Background technology]

[0002] Electronic components used in electronic devices such as mobile phones, smartphones, and notebook computers are becoming increasingly densely integrated and mounted. One known raw material composition for materials such as substrates, adhesives, and encapsulants used in these electronic components is a composition containing a bismaleimide compound and a filler. For example, Patent Document 1 discloses a resin composition containing a bismaleimide compound of a specific structure, a maleimide compound of a specific structure, a photocuring initiator, and a filler. Patent Document 2 also discloses a curable resin composition containing an aliphatic bismaleimide compound, an aliphatic monomaleimide compound, a polymerization initiator, and an inorganic filler. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2024 / 162321 [Patent Document 2] International Publication No. 2024 / 202375 [Overview of the project] [Problems that the invention aims to solve]

[0004] In recent years, the field of electronic devices has demanded the transmission and reception of larger amounts of data at higher speeds, and the practical application of so-called fifth-generation mobile communication systems (5G) is progressing. Along with this, the frequency of transmission signals is being increased, but as the transmission signal frequency increases, a problem arises in that the attenuation (transmission loss) of the transmission signal increases. For this reason, curable compositions used in interlayer insulating materials for printed circuit boards and encapsulating materials for display elements are required to be able to impart dielectric properties such as low dielectric constant and low dielectric loss tangent.

[0005] One known method for obtaining a curable composition that can impart excellent dielectric properties is to increase the content of fillers in the curable composition (to increase the content ratio). However, increasing the filler content can sometimes adversely affect the mechanical properties of the resulting component, such as reducing its elastic modulus.

[0006] The present invention has been made in view of the above problems, and aims to provide a bismaleimide compound that does not easily degrade the mechanical properties of the resulting cured product even when the filler content in the curable composition is high, a curable composition containing the bismaleimide compound, and a cured product obtained from the curable composition. [Means for solving the problem]

[0007] The present invention provides the following embodiments of the invention. <1> A bismaleimide compound represented by the following general formula (I). [ka] (In the formula, R 1 X is an alkylene chain or alkenylene chain having 12 to 24 carbon atoms, having at least one substituent selected from the group consisting of alkyl groups having 1 to 4 carbon atoms and alkenyl groups having 2 to 4 carbon atoms. 1 ~X 4 These are, independently, hydrogen, a methyl group, or a halogen. <2> The aforementioned R 1The bismaleimide compound according to <1>, wherein is a C12-24 alkylene chain or alkenylene chain having at least one C1-4 alkyl group or at least one C2-4 alkenyl group. <3> The R 1 The bismaleimide compound according to <1>, wherein is a C12-24 alkylene chain or alkenylene chain having one C1-4 alkyl group or one C2-4 alkenyl group. <4> A curable composition comprising the bismaleimide compound according to any one of <1> to <3>. <5> The curable composition according to <4>, wherein the curable composition further comprises a filler. <6> The curable composition according to <5>, wherein the content of the filler is 40% by mass or more. <7> The curable composition according to <6>, wherein the viscosity at 25°C is 100 Pa·s or less. <8> The curable composition according to any one of <4> to <7>, wherein the curable composition further comprises a polymerizable compound other than the bismaleimide compound. <9> The curable composition according to <8>, wherein the polymerizable compound has a fused polycyclic hydrocarbon structure and a polymerizable functional group bonded to the fused polycyclic hydrocarbon structure. <10> A cured product obtained from the curable composition according to any one of <4> to <9>. Effects of the Invention

[0008] The bismaleimide compound of the present invention has a structure in which two maleimide groups are bonded via a specific alkylene chain or alkenylene chain. By using the bismaleimide compound, a cured product whose mechanical properties are less likely to deteriorate can be obtained even when the content of the filler in the curable composition is high. Furthermore, by using the bismaleimide compound of the present invention, a curable composition having low viscosity can be obtained. Mode for Carrying Out the Invention

[0009] In the present invention, (meth)acryl means acrylic and / or methacrylic, and (meth)acryloyl means acryloyl and / or methacryloyl, respectively.

[0010] 1. Bismaleimide Compound [Structure, etc. of Bismaleimide Compound] The bismaleimide compound of the present invention has a structure represented by the following general formula (I).

Chemical Formula

[0011] From the viewpoint of improving the effect of the present invention, the alkyl group contained in the alkylene chain or alkenylene chain is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group, and still more preferably an ethyl group.

[0012] From the viewpoint of improving the effect of the present invention, the alkenyl group contained in the alkylene chain or alkenylene chain is preferably an alkenyl group having 2 to 3 carbon atoms, more preferably a vinyl group.

[0013] The alkylene chain or alkenylene chain may have one of said substituents, or may have two or more of said substituents of the same or different types. From the viewpoint of improving the effect of the present invention, the alkylene chain or alkenylene chain preferably has at least one of said alkyl groups or said alkenyl groups, and more preferably has one of said alkyl groups or said alkenyl groups.

[0014] From the viewpoint of improving the effect of the present invention, the number of carbon atoms in the alkylene chain or alkenylene chain is preferably 14 to 22, more preferably 16 to 20.

[0015] The alkylene chain does not have a double bond in the chain. The alkenylene chain has one or more double bonds in the chain, and may have two or more double bonds.

[0016] Examples of the halogen include chlorine, bromine and iodine, and chlorine is preferred from the viewpoint of improving the effect of the present invention.

[0017] Said X 1 ~X 4 from the viewpoint of improving the effect of the present invention, each is preferably independently hydrogen or a methyl group, and more preferably hydrogen.

[0018] From the viewpoint of handleability, the bismaleimide compound is preferably liquid at 25°C and has a viscosity of 5 Pa·s or less at 25°C.

[0019] [Method for Producing Bismaleimide Compound] The bismaleimide compound of the present invention can be obtained by a known method. For example, in a solvent containing an acid catalyst at a temperature of 0°C to 50°C, R in the general formula (I) 1 can be obtained by reacting a diamine having an alkylene chain or alkenylene chain represented by with maleic anhydride to obtain maleamic acid, and then subjecting the maleamic acid to dehydration ring closure (maleimidation) at a temperature of 50°C to 200°C.

[0020] Examples of the solvent include hydrocarbon solvents such as toluene, xylene (o-xylene, m-xylene, p-xylene), ethylbenzene and mesitylene; amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide and N-methyl-2-pyrrolidone (NMP); and mixed solvents of the foregoing.

[0021] Examples of acid catalysts include sulfuric acid, formic acid, methanesulfonic acid, benzenesulfonic acid, orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid, phosphorous acid, hypophosphoric acid, maleic acid, and cationic ion exchange resins. Triethylamine salts of these acids may also be used.

[0022] The obtained bismaleimide compound may be purified by known methods such as crystallization, reprecipitation, and washing with water.

[0023] 2.Curable composition [Composition of curable composition] The curable composition of the present invention contains at least one bismaleimide compound of the present invention. The composition may contain one bismaleimide compound of the present invention, or two or more. The curable composition of the present invention may also contain bismaleimide compounds other than the bismaleimide compound of the present invention, but from the viewpoint of improving the effects of the present invention, it is preferable that the content of bismaleimide compounds other than the bismaleimide compound of the present invention is small, and it is more preferable that it does not contain bismaleimide compounds other than the bismaleimide compound of the present invention. If the curable composition of the present invention contains bismaleimide compounds other than the bismaleimide compound of the present invention, the content thereof is, for example, 100 parts by mass or less per 100 parts by mass of the bismaleimide compound of the present invention, and from the viewpoint of improving the effects of the present invention, it is preferably 50 parts by mass or less, more preferably 10 parts by mass or less, even more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, and particularly preferably 1 part by mass or less.

[0024] The content of the bismaleimide compound of the present invention in the curable composition of the present invention is not particularly limited and can be adjusted as appropriate. The lower limit of the content of the bismaleimide compound of the present invention in the curable composition of the present invention is not particularly limited, but from the viewpoint of easily exhibiting the effects obtained by the bismaleimide compound of the present invention in the resulting cured product, it is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 7% by mass or more, in 100% by mass of the curable composition of the present invention. When the content of the bismaleimide compound of the present invention in the curable composition of the present invention is low, the bismaleimide compound of the present invention can also be considered as an improving agent that improves the mechanical properties such as toughness of the resulting cured product.

[0025] The upper limit of the content of the bismaleimide compound of the present invention in the curable composition of the present invention is not particularly limited. However, from the viewpoint of exhibiting functions derived from other components when the curable composition of the present invention contains other components, the content is preferably 99% by mass or less, more preferably 80% by mass or less, even more preferably 70% by mass or less, and particularly preferably 60% by mass or less, based on 100% by mass of the curable composition of the present invention.

[0026] The curable composition of the present invention may contain other components besides the bismaleimide compound. Examples of other components include fillers, resins such as epoxy resins, phenolic resins, polyimide resins, polyamideimide resins, and (meth)acrylic resins, polymerizable compounds other than the bismaleimide compound (hereinafter also simply referred to as "polymerizable compounds"), polymerizable monomers such as benzoxazine compounds, crosslinking agents, curing agents, and polymerization initiators (thermal polymerization initiators, photopolymerization initiators, etc.). These may be present individually or in combination of two or more.

[0027] The curable composition of the present invention preferably contains a polymerizable compound from the viewpoint of the resulting cured product having excellent hardness and heat resistance. The polymerizable compound is not particularly limited as long as it has at least one polymerizable functional group. A polymerizable functional group means a functional group that is polymerizable, and examples include groups having an ethylenically unsaturated double bond such as vinyl groups, allyl groups, maleimide groups, (meth)acryloyl groups, (meth)acryloyloxy groups, and (meth)acrylamide groups, epoxy groups, and functional groups containing these groups (for example, functional groups containing these groups and hydrocarbon groups and / or heteroatoms). The polymerizable compound preferably has a condensed polycyclic hydrocarbon structure and a polymerizable functional group bonded to the condensed polycyclic hydrocarbon structure. The polymerizable functional group may be directly bonded to the condensed polycyclic hydrocarbon structure, or it may be bonded via other atoms or groups of atoms. Examples of other atoms or groups of atoms include oxygen atoms, nitrogen atoms, sulfur atoms; alkylene groups and arylene groups, which may have substituents. As for the atomic group, alkylene groups having 1 to 5 carbon atoms are preferred, and alkylene groups having 1 to 3 carbon atoms are more preferred, from the viewpoint of the heat resistance of the resulting cured product (hereinafter also simply referred to as "heat resistance"). Examples of polymerizable compounds include a condensed polycyclic hydrocarbon structure and a polymerizable compound having two or more polymerizable functional groups bonded to the condensed polycyclic hydrocarbon structure (hereinafter also referred to as "polymerizable compound (A1)"), and a condensed polycyclic hydrocarbon structure and a polymerizable compound having one polymerizable functional group bonded to the condensed polycyclic hydrocarbon structure (hereinafter also referred to as "polymerizable compound (A2)").

[0028] Polymerizable compound (A1) has a condensed polycyclic hydrocarbon structure and two or more polymerizable functional groups bonded to the condensed polycyclic hydrocarbon structure. In other words, polymerizable compound (A1) is a condensed polycyclic hydrocarbon compound having two or more polymerizable functional groups. Examples of condensed polycyclic hydrocarbon structures include aliphatic condensed polycyclic hydrocarbon structures and aromatic condensed polycyclic hydrocarbon structures. Polymerizable compound (A1) preferably has an aliphatic condensed polycyclic hydrocarbon structure. Examples of aliphatic condensed polycyclic hydrocarbon structures include saturated cycloalkyl structures such as bicyclopentane, bicycloheptane, and bicyclooctane; unsaturated tricyclo[5.2.1.0(2,6)]decane structures containing ethylenically unsaturated bonds, such as dicyclopentadiene structures; adamantane structures; and tricyclic aliphatic condensed polycyclic hydrocarbon structures such as tricyclo[4.3.1.1(3,8)]undecane and tricyclo[6.2.1.0(1,6)]undecane. The number of carbon atoms in the aliphatic condensed polycyclic hydrocarbon structure is not particularly limited, but from the viewpoint of heat resistance and compatibility, it is preferably 8 to 24, more preferably 10 to 20, and even more preferably 12 to 16. From the viewpoint of heat resistance and compatibility, a tricyclic aliphatic condensed polycyclic hydrocarbon structure is preferred, a tricyclic aliphatic condensed polycyclic hydrocarbon structure is more preferred, a tricyclodecane structure is more preferred, and a tricyclo[5.2.1.0(2,6)]decane structure is particularly preferred.

[0029] Examples of aromatic condensed polycyclic hydrocarbon structures include bicyclic aromatic condensed polycyclic hydrocarbon structures such as indene structures, naphthalene structures, and azulene structures; tricyclic aromatic condensed polycyclic hydrocarbon structures such as anthracene structures and phenanthrene structures; and tetracyclic aromatic condensed polycyclic hydrocarbon structures such as naphthacene structures, triphenylene structures, pyrene structures, and chrysene structures. The number of carbon atoms in the aromatic condensed polycyclic hydrocarbon structure is not particularly limited, but from the viewpoint of heat resistance and compatibility, it is preferably 8 to 32, more preferably 10 to 24, and even more preferably 12 to 16. From the viewpoint of heat resistance and compatibility, bicyclic aromatic condensed polycyclic hydrocarbon structures are preferred, and naphthalene structures are more preferred.

[0030] The polymerizable compound (A1) has two or more polymerizable functional groups. The number of polymerizable functional groups is not particularly limited as long as there are two or more, but from the viewpoint of keeping the coefficient of linear expansion of the cured product low to a certain extent while keeping the flexural modulus of elasticity high to a certain extent, it is preferably 2 to 4, more preferably 2 to 3, and even more preferably 2.

[0031] The polymerizable compound (A1) preferably has at least one of its two or more polymerizable functional groups having an ethylenically unsaturated double bond or a functional group containing such a group, and more preferably has two or more polymerizable functional groups having an ethylenically unsaturated double bond or a functional group containing such a group. The groups having an ethylenically unsaturated double bond are preferably (meth)acryloyl groups, (meth)acryloyloxy groups, and allyl groups, with (meth)acryloyl groups being more preferred. The polymerizable compound (A1) may also have other groups besides the polymerizable functional groups on its condensed polycyclic hydrocarbon structure. Examples of other groups include alkyl groups and alkyl halides.

[0032] Examples of polymerizable compounds (A1) include compounds represented by the following formula (II). Polymerizable compound (A1) may contain one compound represented by the following formula (II), or it may contain two or more. Examples of combinations of two or more compounds represented by the following formula (II) include combinations of compounds in which the sum of n and m values ​​of each compound is the same (however, the values ​​of n and m in each compound may be different), and the bonding sites between the tricyclodecane structure and the group containing the (meth)acryloyl group are different. [ka] (In the formula, R 2 and R 3 Each of the elements is independently either H or CH3, X is a saturated or unsaturated tricyclodecane structure, and n and m are independently integers between 1 and 3.

[0033] In formula (II), R 2 and R 3Each of these is independently H or CH3, and from the viewpoint of excellent hardness and heat resistance of the resulting cured product, CH3 is preferred. In formula (II), n and m are each independently integers from 1 to 3, and from the viewpoint of heat resistance, they are preferably 1 or 2, and more preferably 1. Examples of compounds represented by formula (II) include tricyclodecanedimethanol diacrylate (TCD-DA) and tricyclodecanedimethanol dimethacrylate (TCD-DMA).

[0034] Polymerizable compound (A2) has a condensed polycyclic hydrocarbon structure and one polymerizable functional group bonded to the condensed polycyclic hydrocarbon structure. In other words, polymerizable compound (A2) is a condensed polycyclic hydrocarbon compound having one polymerizable functional group. Polymerizable compound (A2) is the same as polymerizable compound (A1) except that the number of polymerizable functional groups is different, so the explanation of the common parts will be omitted.

[0035] Examples of polymerizable compounds (A2) include compounds represented by the following formula (III). Polymerizable compounds (A2) may contain one compound represented by the following formula (III), or two or more. Examples of combinations of two or more compounds represented by the following formula (III) include combinations of compounds in which Y and l are the same, but the bonding sites between the tricyclodecane structure and the group containing the (meth)acryloyl group are different. [ka] (In the formula, R 4 (where is H or CH3, X is a saturated or unsaturated tricyclodecane structure, Y is N, O, S or a single bond, and l is an integer from 0 to 4.)

[0036] In formula (III), R 4is H or CH3, and is preferably CH3 from the viewpoint of excellent hardness and heat resistance of the resulting cured product. In formula (III), l is an integer from 0 to 4, and is preferably 1 or 2, and more preferably 1, from the viewpoint of heat resistance. Examples of compounds represented by formula (III) include dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentenyloxyalkyl (meth)acrylate. Examples of dicyclopentenyloxyalkyl (meth)acrylates include dicyclopentenyloxymethyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentenyloxypropyl (meth)acrylate, and dicyclopentenyloxybutyl (meth)acrylate.

[0037] The polymerizable compound may be a single compound or a combination of two or more compounds. When the polymerizable compound includes two or more compounds, examples include a combination of polymerizable compounds having the same condensed polycyclic hydrocarbon structure, a combination of polymerizable compounds having the same polymerizable functional group, and a combination of polymerizable compounds having the same condensed polycyclic hydrocarbon structure and the same polymerizable functional group. Furthermore, when the polymerizable compound includes two or more compounds, the number of polymerizable functional groups may be the same or different. Among these, a combination of polymerizable compounds having the same condensed polycyclic hydrocarbon structure and the same polymerizable functional group is preferred.

[0038] Examples of combinations of polymerizable compounds having the same condensed polycyclic hydrocarbon structure and the same polymerizable functional group include combinations of polymerizable compounds where the bonding positions of the polymerizable functional group on the condensed polycyclic hydrocarbon structure are different. Furthermore, if the polymerizable compound comprises two or more compounds, and these two or more compounds have the same polymerizable functional group, then polymerizable compounds in which the polymerizable functional group and the condensed polycyclic hydrocarbon structure are directly bonded and polymerizable compounds in which the polymerizable functional group and the condensed polycyclic hydrocarbon structure are bonded via other atoms or groups of atoms may be mixed. In addition, if the polymerizable compound comprises two or more compounds, a preferred embodiment is a combination of polymerizable compounds having the same condensed polycyclic hydrocarbon structure and the same polymerizable functional group, where the bond between the polymerizable functional group and the condensed polycyclic hydrocarbon structure is the same, and where the bonding positions of the polymerizable functional group on the condensed polycyclic hydrocarbon structure are different.

[0039] The polymerizable compound is preferably in liquid state under atmospheric pressure and at room temperature. Furthermore, the glass transition temperature (Tg) of the polymerizable compound is preferably 100°C or higher from the viewpoint of the heat resistance of the resulting cured product.

[0040] The glass transition temperature (Tg) of a polymerizable compound can be measured by the following method. The polymerizable compound and polymerization initiator are injected into a mold (a 100mm x 100mm region is formed between two glass plates with release films attached to each plate, and the release film surfaces are facing each other, using a 4mm thick silicon spacer, with the silicon spacer sandwiched between the two glass plates with a gap of approximately 2-4mm). Ultraviolet light (wavelength: 365nm) is irradiated onto the mold for 1 hour using an LED exposure machine to obtain a polymer. 10mg of the obtained polymer is weighed out and attached to a differential scanning calorimeter (DSC7000X, manufactured by Hitachi High-Tech Science Corporation). Measurements are taken at a heating rate of 10°C / min and a temperature range of -130 to 100°C. The temperature of the endothermic peak originating from the polymer during the first heating process is taken as the glass transition temperature (Tg) of the polymer, and this is taken as the Tg of the polymerizable compound.

[0041] The polymerizable compound content in the curable composition of the present invention is not particularly limited, but from the viewpoint of making the viscosity of the curable composition easy to handle, it is preferably 5 to 70% by mass, more preferably 10 to 65% by mass, and even more preferably 20 to 50% by mass, of 100% by mass of the curable composition of the present invention.

[0042] As one embodiment of the curable composition of the present invention, the total proportion of the bismaleimide compound and polymerizable compound of the present invention in the total components excluding fillers and solvents that may be contained in the curable composition of the present invention may be 1% by mass or more, 3% by mass or more, 20% by mass or more, 30% by mass or more, or 40% by mass or more, or 100% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, or 60% by mass or less, from the viewpoint of making the viscosity of the curable composition within a range that is easy to handle and from the viewpoint of excellent hardness and heat resistance of the resulting cured product, or from the viewpoint of 100% by mass of all components excluding fillers and solvents.

[0043] The curable composition of the present invention preferably contains a filler in order to impart excellent dielectric properties to the cured product.

[0044] Examples of fillers include silica (e.g., natural silica, fused silica, amorphous silica, spherical silica, and hollow silica), aluminum compounds (e.g., boehmite, aluminum hydroxide, alumina, and aluminum nitride), boron compounds (e.g., boron nitride), magnesium compounds (e.g., magnesium oxide and magnesium hydroxide), calcium compounds (e.g., calcium carbonate), molybdenum compounds (e.g., molybdenum oxide and zinc molybdate), barium compounds (e.g., barium sulfate and barium silicate), talc (e.g., natural talc and calcined talc), mica, glass (e.g., short-fiber glass, spherical glass, fine-powdered glass, E-glass, T-glass, and D-glass), silicone powder, fluororesin-based fillers, urethane resin-based fillers, (meth)acrylic resin-based fillers, polyethylene-based fillers, styrene-butadiene rubber, and silicone rubber. These may be used individually or in combination of two or more. Of these, silica is preferred.

[0045] When the curable composition of the present invention contains a filler, the content of the filler is not particularly limited and can be adjusted as appropriate. However, from the viewpoint of the cured product exhibiting excellent dielectric properties and improving the mechanical properties such as the elastic modulus of the cured product, the filler content is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 50% by mass or more, and also preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, and particularly preferably 75% by mass or less, in 100% by mass of the curable composition of the present invention. Generally, increasing the filler content in a curable composition tends to decrease the mechanical properties such as the elastic modulus of the cured product. However, since the curable composition of the present invention contains the bismaleimide compound of the present invention, it is possible to effectively suppress the decrease in the mechanical properties of the cured product even when the filler content is high.

[0046] When the curable composition of the present invention contains a filler, the curable composition of the present invention preferably has a viscosity of 100 Pa·s or less at 25°C, more preferably 50 Pa·s or less, even more preferably 40 Pa·s or less, even more preferably 30 Pa·s or less, and particularly preferably 25 Pa·s or less, from the viewpoint of handling and other factors.

[0047] [Uses of curable compositions] The curable composition of the present invention can be used in a wide range of applications, including core substrates and coverlay films of flexible printed circuit boards (FPCs), copper-clad laminates, passivation films, protective films, and interlayer insulating films on the surface of semiconductor elements in semiconductor devices, as well as conformal coatings for printed circuit boards, surface protective films for solar cells, alignment films for liquid crystal surface elements, protective films for glass fibers, printing paste compositions, and conductive paste compositions.

[0048] 3.Cured product The cured product of the present invention is obtained by curing the curable composition of the present invention. A method for producing the cured product includes, for example, applying the curable composition of the present invention to a substrate or various other materials to form a desired shape, and then curing the composition by heating or irradiating it with light (e.g., ultraviolet light). However, the method is not limited to this, and known methods can be used depending on the purpose and application of forming the cured product. The curing conditions are appropriately adjusted according to the curable composition used. [Examples]

[0049] The present invention will be described below with reference to examples, but the present invention is not limited in any way by these examples.

[0050] Manufacturing Example 1 In a 1 L flask equipped with a reflux condenser with water separator, a stirrer, and a thermometer, 400 g of toluene, 0.41 moles of 8-ethyl-1,18-octadecanediamine (Okamura Oil Co., Ltd., Diamine H2O), 1.02 moles of maleic anhydride, 0.82 moles of methanesulfonic acid, and 0.41 moles of triethylamine were added under a nitrogen atmosphere. The mixture was heated and stirred, and the temperature was increased, and the mixture was heated under reflux for 15 hours to obtain a two-phase solution. The obtained solution was washed with pure water, and the solvent was removed by distillation to obtain bismaleimide compound 1, represented by the following formula, in 96% yield. Bismaleimide compound 1 is liquid at 25°C. Furthermore, the viscosity of bismaleimide compound 1 at 25°C was 1.2 Pa·s. A rotational viscometer TV-100EH manufactured by Toki Sangyo Co., Ltd. was used to measure the viscosity. 1 1H NMR spectrum and 13 ¹³C NMR was measured at 25°C using a nuclear magnetic resonance (NMR) spectrometer ("AVANCE NEO" manufactured by Bruker Corporation). Deuterated chloroform was used as the measurement solvent, and the chemical shift values ​​were calibrated using the signals of tetramethylsilane and the solvent. 1 1H NMR spectrum and 13 The 13C NMR spectrum also includes the spectra of unavoidable impurities such as structural isomers of bismaleimide compound 1. 1H NMR(500MHz,CDCl3,ppm)δ=6.68(s,4H),3.50(t,J=7.3Hz,4H),1.57(quintet,J=7.3Hz,4H ),1.28-1.19(m,29H),0.84(minor)(t,J=7.2Hz,0.81H),0.82(major)(t,J=7.2Hz,2.19H) 13 C NMR(125MHz,CDCl3,ppm)δ=170.68,133.88,41.08,41.06,38.66,37.75,33.04,33.01,30.07,30.05,29.95,29.79,29.48 ,29.40,29.32,29.01,28.96,28.38,27.88,27.84,26.61,26.59,26.57,26.48,25.72,23.03,22.99,13.87,12.48,10.72 [ka]

[0051] Manufacturing Example 2 Bismaleimide compound 2, represented by the following formula, was obtained in 95% yield by the same method as in Production Example 1, except that diamine H2O was replaced with 0.41 moles of dimeramine (Cargill, Priamine 1075). Bismaleimide compound 2 is liquid at 25°C. Furthermore, the viscosity of bismaleimide compound 2 at 25°C was 3.5 Pa·s. The viscosity was measured using the aforementioned viscometer. [ka]

[0052] Example 1 50 parts by mass of bismaleimide compound 1 were mixed with 50 parts by mass of spherical silica (particle size: approximately 2 μm, manufactured by Tianjin Zexi Mineral Processing Co., Ltd., product name: SSF-002) and 1 part by mass of polymerization initiator (manufactured by NOF Corporation, Perbutyl P®). The mixture was stirred for 60 seconds at atmospheric pressure and a rotational speed of 2,000 rpm using a rotary-rotating stirrer (manufactured by Thinky Co., Ltd., Awatori Rentaro ARV-310P) to obtain a curable composition. The resulting curable composition had a viscosity of 13.76 Pa·s at 25°C. The viscosity was measured using the aforementioned viscometer. The obtained curable composition was applied to a commercially available polytetrafluoroethylene substrate, a 2 mm thick spacer was placed around it, and another polytetrafluoroethylene substrate was placed on top of it, so that the curable composition filled a 2 mm thick space (cell). Then, the cell was left to stand in a heater set to 200°C for 60 minutes to cure the curable composition and obtain a cured product with a thickness of 2 mm.

[0053] Example 2, Comparative Examples 1 and 2 Each curable composition was obtained in the same manner as in Example 1, except that the components and their proportions (parts by mass) were changed as shown in Table 1. The viscosity of each obtained curable composition at 25°C was measured using the viscometer described above. The results are shown in Table 1. Furthermore, using each of the obtained curable compositions, a cured product with a thickness of 2 mm was obtained by the same method as in Example 1.

[0054] Examples 3-7 Each curable composition was obtained in the same manner as in Example 1, except that the components and their proportions (parts by mass) were changed as shown in Table 2. The viscosity of each obtained curable composition at 25°C was measured using the viscometer described above. The results are shown in Table 2. Furthermore, using each of the obtained curable compositions, a cured product with a thickness of 2 mm was obtained by the same method as in Example 1.

[0055] <Measurement of linear expansion coefficient (CTE)> Each hardened material was cut to create test specimens measuring 5 mm in width, 5 mm in length, and 2 mm in thickness. Using a thermomechanical analysis (TMA) instrument (NETZCH JAPAN, TMA 4000SA), thermal expansion was measured for each specimen under conditions of a heating rate of 5°C / min, a load of 5.0 g, and a nitrogen atmosphere, until the temperature exceeded 200°C. The linear expansion coefficient (ppm / °C) for each specimen in the 120-150°C range was calculated from the obtained thermal expansion values. The results are shown in Tables 1 and 2.

[0056] <Measurement of flexural modulus> Each hardened material was cut to create test specimens measuring 50 mm in width, 10 mm in length, and 2 mm in thickness. Using testing machines (IMADA ZTS-200N and EMX-500N), the displacement and stress were measured at a speed of 1 mm / min until each specimen fractured. The flexural modulus (GPa) of each specimen was calculated from the resulting stress-strain diagrams. The results are shown in Tables 1 and 2.

[0057] [Table 1]

[0058] [Table 2]

[0059] The results in Tables 1 and 2 show that by using the bismaleimide compound of the present invention, the deterioration of the mechanical properties of the resulting cured product can be effectively suppressed even when the filler content in the curable composition is high (50% by mass or more). Furthermore, it can be seen that a curable composition with low viscosity can be obtained by using the bismaleimide compound of the present invention.

Claims

1. A bismaleimide compound represented by the following general formula (I). 【Chemistry 1】 (In the formula, R 1 X is an alkylene chain or alkenylene chain having 12 to 24 carbon atoms, having at least one substituent selected from the group consisting of alkyl groups having 1 to 4 carbon atoms and alkenyl groups having 2 to 4 carbon atoms. 1 ~X 4 These are, independently, hydrogen, a methyl group, or a halogen.

2. The aforementioned R 1 The bismaleimide compound according to claim 1, wherein is a 12-24 C alkylene chain or alkenylene chain having at least one C1-C4 alkyl group or C2-C4 alkenyl group.

3. The aforementioned R 1 The bismaleimide compound according to claim 1, wherein is a 12-24 alkylene chain or alkenylene chain having one C1-C4 alkyl group or one C2-C4 alkenyl group.

4. A curable composition comprising the bismaleimide compound described in claim 1.

5. The curable composition according to claim 4, further comprising a filler.

6. The curable composition according to claim 5, wherein the filler content is 40% by mass or more.

7. The curable composition according to claim 6, wherein the viscosity at 25°C is 100 Pa·s or less.

8. The curable composition according to claim 4, further comprising a polymerizable compound other than the bismaleimide compound.

9. The curable composition according to claim 8, wherein the polymerizable compound has a condensed polycyclic hydrocarbon structure and a polymerizable functional group bonded to the condensed polycyclic hydrocarbon structure.

10. A cured product obtained from the curable composition according to any one of claims 4 to 9.

Images