Multifunctional vinyl compound, composition thereof, and cured product

Abstract

The present invention provides a vinyl compound that has excellent solvent solubility, that provides a cured product having excellent heat resistance, thermal decomposition stability, thermal conductivity, low dielectric constant, low dielectric tangent, and flame retardance, and that is useful for sealing electrical and electronic components and is useful as a circuit board material or the like.　Provided is a multifunctional vinyl compound represented by general formula (1). In formula (1), each R1 independently represents a hydrogen atom, a fluorine atom, a methoxy group, or a monovalent hydrocarbon group having 1-6 carbon atoms. R2-R4 each independently represent a hydrogen atom, a hydroxy group, a fluorine atom, a methoxy group, a monovalent hydrocarbon group having 1-6 carbon atoms, or a vinylbenzyl ether group. n represents a number of 1-15.

Description

Polyfunctional vinyl compound, composition thereof, and cured product

[0001] The present invention relates to a vinyl compound, and more particularly to a polyfunctional vinyl compound having excellent solvent solubility and useful as an insulating material for electric and electronic components such as semiconductor encapsulation, laminates, and heat dissipation substrates; a composition thereof; and a cured resin product obtained by curing the compound or the composition, which has excellent heat resistance, thermal decomposition stability, thermal conductivity, low dielectric constant, low dielectric dissipation factor, and flame retardancy.

[0002] As communication speeds and volumes increase, research into high-speed communication technologies is actively underway to improve signal transmission speeds for printed circuit boards, encapsulants, and casting materials used in communication devices. Electronic materials for such applications require materials that can reduce dielectric loss, and for printed circuit board applications, curable resins that can be multilayered are also required.

[0003] On the other hand, electronic computing components that process such large amounts of data generate a lot of heat, and heat accumulation can cause problems such as a decrease in the processing speed of the electronic computing components, so various methods have been known to appropriately cool printed circuit boards using heat sinks or the like, such as incorporating heat transfer members such as copper coins and copper inlays (Patent Document 1), or using fillers with special shapes (Patent Document 2).However, these methods are undesirable because they lead to increased weight and larger equipment.

[0004] In encapsulant compositions, methods for increasing thermal conductivity have been adopted to remove heat from electronic computing components by examining the type and amount of various fillers. For example, attempts have been made to incorporate inorganic fillers with high thermal conductivity, such as crystalline silica, silicon nitride, aluminum nitride, and spherical alumina powder (Patent Documents 3 and 4). However, increasing the content of inorganic fillers increases viscosity during molding, reducing fluidity and impairing moldability. Therefore, there are limitations to simply increasing the content of inorganic fillers.

[0005] Given the above background, methods for improving the thermal conductivity of compositions by increasing the thermal conductivity of the matrix resin itself have also been investigated. For example, liquid crystalline epoxy resins with rigid mesogenic groups and epoxy resin compositions using such resins have been proposed (Patent Documents 5 and 6). However, these epoxy resin compositions use aromatic diamine compounds as curing agents, which limit the high inorganic filler loading and also pose problems with electrical insulation. Furthermore, when aromatic diamine compounds are used, although liquid crystallinity can be confirmed in the cured product, the degree of crystallinity of the cured product is low, and it is insufficient in terms of high thermal conductivity, low thermal expansion, low moisture absorption, etc. Furthermore, to achieve liquid crystallinity, a strong magnetic field must be applied to orient the molecules, which poses significant equipment limitations for widespread industrial use.

[0006] Patent Document 7 discloses a tetra- or higher functional vinyl resin having a biphenyl skeleton as a multifunctional vinyl resin that achieves both high thermal conductivity and low dielectric tangent. However, it does not describe the solvent solubility of the multifunctional vinyl resin or the polyhydric hydroxyl resin that is its raw material, and it does not mention at all the influence that impurities such as residual polar groups have on thermal conductivity.

[0007] JP 2009-170493, WO 2013 / 100172, JP 11-147936, JP 2002-309067, JP 11-323162, JP 9-118673, WO 2021 / 200414

[0008] An object of the present invention is to provide a vinyl composition that has excellent solvent solubility and gives a cured product that is excellent in heat resistance, thermal decomposition stability, thermal conductivity, low dielectric constant, low dielectric dissipation factor, and flame retardancy, and is useful for sealing electric and electronic components, as a circuit board material, etc., and to provide the cured product. Another object is to provide a vinyl compound that can be used in the vinyl composition.

[0009] The present inventors have conducted extensive research and have found that a polyfunctional vinyl compound having a specific structure is expected to solve the above-mentioned problems, and that a cured product thereof exhibits effects in terms of heat resistance, thermal decomposition stability, thermal conductivity, low dielectric constant, low dielectric dissipation factor, and flame retardancy.

[0010] That is, the present invention is a polyfunctional vinyl compound represented by the following general formula (1). In formula (1), R1 independently represents a hydrogen atom, a fluorine atom, a methoxy group, or a monovalent hydrocarbon group having 1 to 6 carbon atoms. R2 to R4 independently represent a hydrogen atom, a hydroxy group, a fluorine atom, a methoxy group, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a vinylbenzyl ether group. n represents a number from 1 to 15.

[0011] The total content of the polyfunctional vinyl compound where n=1 to 3 in terms of GPC area % is preferably 60% or more.

[0012] The present invention relates to a polyfunctional vinyl composition containing the above polyfunctional vinyl compound and a radical polymerization initiator as essential components, and to a cured polyfunctional vinyl product obtained by curing this polyfunctional vinyl composition.

[0013] The polyfunctional vinyl compound of the present invention has excellent solvent solubility and is suitable for use in vinyl compositions and cured products thereof for applications such as lamination, molding, casting, adhesion, etc. Furthermore, the cured products also have excellent heat resistance, thermal decomposition stability, thermal conductivity, low dielectric constant, low dielectric dissipation factor, and flame retardancy, making them suitable for sealing electric and electronic components, circuit board materials, etc.

[0014] 1 is a GPC chart of the polyfunctional hydroxy compound obtained in Synthesis Example 1. FIG. 2 is a GPC chart of the polyfunctional vinyl compound obtained in Example 1.

[0015] The present invention will be described in detail below.

[0016] The present invention is a polyfunctional vinyl compound represented by the following general formula (1). R1 independently represents a hydrogen atom, a fluorine atom, a methoxy group, or a monovalent hydrocarbon group having 1 to 6 carbon atoms. R2 to R4 independently represent a hydrogen atom, a hydroxy group, a fluorine atom, a methoxy group, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a vinylbenzyl ether group. R1 to R4 are preferably alkyl groups or methoxy groups from the viewpoint of solvent solubility, aromatic groups from the viewpoint of heat resistance and high thermal conductivity, and fluorine atoms from the viewpoint of dielectric properties. Alkyl groups with more than 6 carbon atoms make it difficult to suppress molecular motion, raising concerns about reduced compatibility. Furthermore, bulky structures with significant steric hindrance raise concerns about solvent solubility due to increased crystallinity. When any of R2 to R4 is a vinylbenzyl ether group, the crosslink density of the cured product is improved, making it suitable for heat resistance and high thermal conductivity. More preferred structures for R1 to R4 are hydrogen atoms, methyl groups, or methoxy groups. A mixture of different structures for R1 to R4 is also acceptable.

[0017] The number-average molecular weight (Mn) of the polyfunctional vinyl compound of the present invention is preferably 2000 or less, more preferably 1500 or less. n is the number of repeating units and represents a number from 0 to 15. Preferably, the compound is a mixture of components with different n values. The number-average n value is 1 to 15, preferably 1 to 10, and more preferably 1 to 5. Since the n=0 form has strong crystallinity and there is a concern of reduced solvent solubility, the GPC area percentage is preferably 20 area% or less. A content of n=3 or more of 50 area% or more tends to decrease thermal conductivity. In other words, the total of n=1 and n=2 forms is preferably 50 area% or more. From the viewpoint of thermal conductivity, the content of n=3 or more is preferably 50 area% or less. The total content of n=1 to 3 forms is preferably 55 to 95 area%, more preferably 65 to 90 area%.

[0018] The polyfunctional vinyl compound of the present invention has a vinyl equivalent of preferably 150 to 300 g / eq, more preferably 180 to 250 g / eq. If the vinyl equivalent is less than this range, the reaction will proceed too rapidly, making it difficult to control the reaction. If the vinyl equivalent is greater than this range, the reactivity will decrease, making it difficult to obtain a uniform cured product.

[0019] The polyfunctional vinyl compound of the present invention can be obtained by reacting a polyhydric hydroxy compound with chloromethylstyrene. If the amount of unreacted hydroxyl groups remaining is less than 5,000 g / eq, curing will be insufficient, resulting in reduced thermal conductivity and heat resistance. Furthermore, since hydroxyl groups are polar groups, their remaining presence may hinder the reduction of the dielectric constant and dielectric loss tangent. The hydroxyl group equivalent is preferably 5,000 g / eq or more, more preferably 10,000 g / eq or more. Meanwhile, the chlorine component is derived from the raw material chloromethylstyrene. If chlorine components remain, as with hydroxyl groups, there is a concern that they may hinder the reduction of the dielectric constant and dielectric loss tangent, and that the curing reaction may be inhibited by polar groups, resulting in reduced thermal conductivity and heat resistance. The total chlorine content is preferably 2,000 ppm or less, more preferably 1,000 ppm or less.

[0020] The polyfunctional vinyl compound of the present invention can be obtained by reacting a polyhydric hydroxy compound represented by formula (2) with an aromatic vinylating agent, where R1 and R2 are the same as those in the vinyl compound of formula (1).

[0021] The polyvalent hydroxy compound of formula (2) preferably has a hydroxyl group equivalent of 40 to 180 g / eq, more preferably 60 to 140 g / eq. The number average molecular weight (Mn) is preferably 1,200 or less, more preferably 1,000 or less. The polyvalent hydroxy compound of formula (2) can be produced by a general method, and the production method is not limited as long as it has the predetermined structure. For example, it can be obtained by polycondensation of a divalent phenol compound such as hydroquinone with an aromatic aldehyde. The divalent phenol compound is not limited and known compounds can be used, but as in the case of n = 0 in formula (2), those having R1 as a substituent are used. Here, R1 is also as described above and is independently a hydrogen atom, a fluorine atom, an alkoxy group, or a monovalent hydrocarbon group having 1 to 6 carbon atoms. Among these dihydric phenolic compounds, for example, 2-methoxyhydroquinone can be obtained from plant-derived 4-hydroxy-3-methoxybenzaldehyde (also known as vanillin), making it suitable as a material for saving petroleum resources and reducing carbon dioxide emissions.

[0022] Examples of aromatic aldehydes include benzaldehyde, 4-methylbenzaldehyde, 4-ethylbenzaldehyde, 4-fluorobenzaldehyde, 4-methoxyaldehyde, 4-phenylbenzaldehyde, 3-methylbenzaldehyde, 3-ethylbenzaldehyde, 3-fluorobenzaldehyde, 3-methoxybenzaldehyde, 2-methylbenzaldehyde, 2-ethylbenzaldehyde, 2-fluorobenzaldehyde, 2-methoxybenzaldehyde, 5-fluoro-2-methylbenzaldehyde, 4-fluoro-3-methylbenzaldehyde, 4-fluoro-2-methylbenzaldehyde, 3-fluoro-5-methylbenzaldehyde, 3-fluoro-4-methylbenzaldehyde, 3- Examples of the fluorobenzaldehyde include fluoro-2-methylbenzaldehyde, 2-fluoro-6-methylbenzaldehyde, 2-fluoro-5-methylbenzaldehyde, 2-fluoro-4-methylbenzaldehyde, 2-fluoro-3-methylbenzaldehyde, 2,6-difluorobenzaldehyde, 2,5-difluorobenzaldehyde, 2,4-difluorobenzaldehyde, 2,3-difluorobenzaldehyde, 3,5-difluorobenzaldehyde, 3,4-difluorobenzaldehyde, 2,6-dimethylbenzaldehyde, 2,5-dimethylbenzaldehyde, 2,4-dimethylbenzaldehyde, 2,3-dimethylbenzaldehyde, 3,5-dimethylbenzaldehyde, and 3,4-dimethylbenzaldehyde. Examples of plant-derived aromatic aldehydes include 4-hydroxy-3-methoxybenzaldehyde (also known as vanillin), 3,5-dimethoxy-4-hydroxybenzaldehyde (also known as syringaldehyde), and 4-methoxyaldehyde (also known as anisaldehyde). From the viewpoints of solvent solubility and thermal conductivity, benzaldehyde, 4-methylbenzaldehyde, 4-ethylbenzaldehyde, 4-fluorobenzaldehyde, 4-methoxyaldehyde, 4-hydroxy-3-methoxybenzaldehyde, and 3,5-dimethoxy-4-hydroxybenzaldehyde are preferred. These can also be used in combination.

[0023] The polycondensation of a dihydric phenol compound and an aromatic aldehyde may be carried out using an acid catalyst, such as acetic acid, oxalic acid, sulfuric acid, hydrochloric acid, phenolsulfonic acid, paratoluenesulfonic acid, zinc acetate, manganese acetate, etc. These acid catalysts may be used alone or in combination of two or more. Among these acid catalysts, sulfuric acid and paratoluenesulfonic acid are preferred because of their excellent activity. The acid catalyst may be added before or during the reaction.

[0024] The polycondensation of the dihydric phenol compound and the aromatic aldehyde may be carried out in the presence of a solvent, if necessary, to obtain a polycondensation product. Examples of the solvent include monoalcohols such as methanol, ethanol, and propanol; polyols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, trimethylene glycol, diethylene glycol, polyethylene glycol, and glycerin; glycol ethers such as 2-ethoxyethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl methyl ether, and ethylene glycol monophenyl ether; cyclic ethers such as 1,3-dioxane, 1,4-dioxane, and tetrahydrofuran; glycol esters such as ethylene glycol acetate; and ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone. These solvents can be used alone or in combination of two or more. Among these solvents, 2-ethoxyethanol is preferred because it has excellent solubility for the resulting compound.

[0025] The reaction temperature during polycondensation of the dihydric phenol compound and the aromatic aldehyde is in the range of 20 to 140°C, preferably in the range of 80 to 110°C.

[0026] The charging ratio of the dihydric phenol compound to the aromatic aldehyde is in the range of 1 / 0.1 to 1 / 0.5 in terms of molar ratio, more preferably in the range of 1 / 0.1 to 1 / 0.3, since the phenol compound after the reaction can be easily removed by reprecipitation or the like.

[0027] The polyfunctional vinyl compound of the present invention can be suitably obtained by reacting a polyvalent hydroxy compound with an aromatic vinylating agent. For example, the vinyl compound of the present invention represented by the above formula (1) can be obtained by reacting a polyvalent hydroxy compound represented by the above formula (2) with chloromethylstyrene. This reaction can be carried out in the same manner as well-known vinylation reactions. The blending ratio is preferably 0.5 to 1.5 equivalents, more preferably 0.8 to 1.2 equivalents, of the aromatic vinylating agent (e.g., chloromethylstyrene) per 1.0 equivalent of the hydroxyl group, which is the functional group of the polyvalent hydroxy compound. However, if the reactivity of the polyvalent hydroxy compound is low, it is advisable to charge an excess amount of the aromatic vinylating agent and remove it after the reaction.

[0028] As the aromatic vinylating agent, halomethylstyrene, particularly chloromethylstyrene, is preferred. Other examples include bromomethylstyrene and its isomers, and those having a substituent. Regarding the substitution position of the halomethyl compound, for example, in the case of halomethylstyrene, the 4-position is preferred, and it is preferred that the 4-position compound accounts for 60% by weight or more of the total.

[0029] The reaction between a polyhydric hydroxy compound and an aromatic vinylating agent can be carried out in the absence of a solvent or in the presence of a solvent. The reaction can be carried out by adding the aromatic vinylating agent to the hydroxy compound, adding a metal hydroxide, and removing the resulting metal salt by filtration, washing with water, or other methods. Examples of solvents include, but are not limited to, methyl ethyl ketone, benzene, toluene, xylene, methyl isobutyl ketone, diethylene glycol dimethyl ether, cyclopentanone, and cyclohexanone. From the viewpoint of reactivity, methyl ethyl ketone is preferred. Specific examples of metal hydroxides include, but are not limited to, sodium hydroxide and potassium hydroxide.

[0030] The vinylation reaction is preferably carried out at a temperature of 90° C. or less, more preferably 70° C. or less. At temperatures higher than this temperature, self-polymerization of the vinylbenzyl ether group due to heat proceeds, making it difficult to control the reaction. To suppress self-polymerization, a polymerization inhibitor such as quinones, nitro compounds, nitrophenols, nitroso compounds, nitrone compounds, or oxygen may be used.

[0031] The end point of the reaction can be determined by tracking the remaining amount of halomethylstyrene as an aromatic vinylating agent using various chromatograms such as GPC, and the reaction rate can be adjusted by the type and amount of metal hydroxide, the addition rate, the solids concentration, etc.

[0032] The polyfunctional vinyl compound of the present invention can be cured alone, but it is also suitable to use it as a polyfunctional vinyl composition containing various additives. In particular, to accelerate curing, a radical polymerization initiator such as an azo compound or an organic peroxide can be added to the composition to effect curing. The amount of the radical polymerization initiator is, for example, 0.01 to 3.0 parts by weight, preferably 0.05 to 1.0 parts by weight, per 100 parts by weight of the polyfunctional vinyl compound. An antioxidant may also be added, and the amount is, for example, 0.01 to 3.0 parts by weight, preferably 0.03 to 0.10 parts by weight, per 100 parts by weight of the polyfunctional vinyl compound.

[0033] The polyfunctional vinyl composition of the present invention contains a polyfunctional vinyl compound and a radical polymerization initiator as essential components, but can also contain other vinyl compounds and other thermosetting resins, such as epoxy resins, oxetane resins, maleimide resins, acrylate resins, polyester resins, polyurethane resins, polyphenylene ether resins, and benzoxazine resins.

[0034] To increase thermal conductivity, inorganic fillers such as glass cloth, carbon fiber, alumina, and boron nitride may be blended. Polyfunctional vinyl compositions blended with inorganic fillers are suitable for semiconductor encapsulants and circuit boards. In the case of semiconductor encapsulants, the blending amount of inorganic fillers is, for example, 50% by weight or more, preferably 80 to 90% by weight. In the case of circuit boards, the blending amount of inorganic fillers is, for example, 50% by weight or more, preferably 70 to 90% by weight.

[0035] For the purpose of imparting higher thermal conductivity, inorganic fillers with higher thermal conductivity are preferred. It is preferably 20 W / m K or higher, more preferably 30 W / m K or higher, and even more preferably 50 W / m K or higher. At least a portion of the inorganic filler, preferably 50 wt % or more, has a thermal conductivity of 20 W / m K or higher. The average thermal conductivity of the inorganic filler as a whole increases in order of preference from 20 W / m K or higher, to 30 W / m K or higher, and to 50 W / m K or higher.

[0036] Examples of inorganic fillers having such a thermal conductivity include inorganic powder fillers such as boron nitride, aluminum nitride, silicon nitride, silicon carbide, titanium nitride, zinc oxide, tungsten carbide, alumina, and magnesium oxide.

[0037] Various additives may be added to improve adhesive strength and ease of handling of the composition, such as silane coupling agents, antifoaming agents, internal mold release agents, and flow control agents.

[0038] The polyfunctional vinyl compound or polyfunctional vinyl composition of the present invention can also be dissolved in a solvent such as toluene, xylene, acetone, methyl ethyl ketone, or methyl isobutyl ketone, impregnated into a substrate such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, or paper, and heated and dried to obtain a prepreg, which can then be hot-press molded to obtain a cured product.

[0039] In some cases, the composition can be applied to a sheet-like material such as copper foil, stainless steel foil, polyimide film, or polyester film to form a laminate, and the resin sheet obtained by heating and drying can be hot-press molded to obtain a cured product.

[0040] The present invention will be specifically explained below with reference to examples and comparative examples. However, the present invention is not limited to these. Unless otherwise specified, "parts" means parts by weight, and "%" means % by weight. Measurement methods were as follows.

[0041] 1) OH equivalent (hydroxyl group equivalent) Using a potentiometric titrator, acetylation was carried out with 1.5 mol / L acetyl chloride in 1,4-dioxane as a solvent, and the excess acetyl chloride was decomposed with water, followed by titration with 0.5 mol / L potassium hydroxide.

[0042] 2) Vinyl equivalent: The sample was reacted with Wiess's solution (iodine monochloride solution) and left in the dark. After that, excess iodine chloride was reduced to iodine, and the iodine content was titrated with sodium thiosulfate to calculate the iodine value. The iodine value was converted to vinyl equivalent.

[0043] 3) Total chlorine: 1.0 g of sample was dissolved in 25 ml of butyl carbitol, 25 ml of 1N KOH propylene glycol solution was added, and the mixture was heated under reflux for 10 minutes. After cooling to room temperature, 100 ml of 80% acetone water was added, and the total chlorine was measured by potentiometric titration with a 0.002 N AgNO3 aqueous solution.

[0044] 4) GPC Measurement A main body (Tosoh Corporation, HLC-8220GPC) equipped with four columns (Tosoh Corporation, TSKgel SuperMultipore HZ-N) in series was used, and the column temperature was set to 40°C. Tetrahydrofuran (THF) was used as the eluent at a flow rate of 0.35 mL / min, and a differential refractive index detector was used as the detector. 0.1 g of sample was dissolved in 10 mL of THF and filtered through a microfilter, and 50 μL of the solution was used as the measurement sample. Data processing was performed using Tosoh Corporation's GPC-8020 Model II Version 6.00.

[0045] 5) Solvent solubility (precipitation temperature) 2 g of resin and 1 g of methyl ethyl ketone were weighed into a sample bottle, heated to dissolve, and then the temperature was gradually lowered in a thermostatic chamber, and the temperature in the chamber at which the resin precipitated was measured. The higher the precipitation temperature (°C), the poorer the solvent solubility.

[0046] 6) Glass Transition Point (Tg) Tg was determined using a thermomechanical measuring device (EXSTAR TMA / 7100 manufactured by SII Nanotechnology Inc.) at a temperature rise rate of 10°C / min.

[0047] 7) 5% Weight Loss Temperature (Td5), Carbon Residual Ratio The 5% weight loss temperature (Td5) was measured under a nitrogen atmosphere at a heating rate of 10°C / min using a thermogravimetric / differential thermal analyzer (EXSTAR TG / DTA7300 manufactured by SII Nano Technology). The weight loss at 700°C was also measured and calculated as the carbon residual ratio.

[0048] 8) Thermal Conductivity The thermal conductivity was measured by the transient hot wire method using a thermal conductivity meter LFA447 manufactured by NETZSCH.

[0049] 9) Dielectric constant and dielectric loss tangent Measured in accordance with JIS C 2138. The measurement frequency was 1 GHz.

[0050] Synthesis Example 1 Into a 1000 mL four-neck flask, 110.0 g (1.00 mol) of hydroquinone (structural formula below), Benzaldehyde (structural formula below) 21.2 g (0.20 mol) and dissolved in 200.0 g of 2-ethoxyethanol. While cooling in an ice bath, 19.6 g of sulfuric acid was added, and then the mixture was heated at 100°C for 3 hours with stirring to allow the reaction to proceed. After the reaction, the resulting solution was reprecipitated with water, washed with water, filtered, and vacuum dried to obtain 57.9 g of polyhydroxy compound a. In polyhydroxy compound a, R1 to R4 in formula (2) were all hydrogen atoms, the number average molecular weight was 520, the total GPC area percentage for n = 1 to 3 was 77.9%, and the hydroxyl group equivalent was 91 g / e.g.

[0051] Synthesis Example 2 The same procedure as in Synthesis Example 1 was carried out, except that 24.0 g (0.20 mol) of 4-methylbenzaldehyde (structural formula below) was used instead of 21.2 g of benzaldehyde. 61.8 g of polyhydroxy compound b was obtained. In polyhydroxy compound b, in formula (2), R1 to R3 were hydrogen atoms and R4 was a methyl group, the number average molecular weight was 640, the total GPC area percentage of n=1 to 3 was 86.0%, and the hydroxyl group equivalent was 93 g / e.g.

[0052] Synthesis Example 3 The same procedure as in Synthesis Example 1 was carried out, except that 26.8 g (0.20 mol) of 3,4-dimethylbenzaldehyde (structural formula below) was used instead of 21.2 g of benzaldehyde. 60.5 g of polyhydroxy compound c was obtained. In polyhydroxy compound c, in formula (2), R1 and R2 were hydrogen atoms, and R3 and R4 were methyl groups, the number average molecular weight was 890, the total GPC area percentage for n=1 to 3 was 84.6%, and the hydroxyl group equivalent was 115 g / e.g.

[0053] Synthesis Example 4 The same procedure as in Synthesis Example 1 was carried out, except that 24.8 g (0.20 mol) of 4-fluorobenzaldehyde (structural formula below) was used instead of 21.2 g of benzaldehyde. 60.6 g of polyhydroxy compound d was obtained. In polyhydroxy compound d, in formula (2), R1 to R3 were hydrogen atoms and R4 was a fluorine atom, the number average molecular weight was 840, the total GPC area percentage of n=1 to 3 was 65.2%, and the hydroxyl group equivalent was 95 g / e.g.

[0054] Synthesis Example 5 The same procedure as in Synthesis Example 1 was carried out, except that 27.2 g (0.20 mol) of 4-methoxybenzaldehyde (structural formula below) was used instead of 21.2 g of benzaldehyde. 61.5 g of polyhydroxy compound e was obtained. In polyhydroxy compound e, in formula (2), R1 to R3 were hydrogen atoms and R4 was a methoxy group, the number average molecular weight was 890, the total GPC area percentage of n=1 to 3 was 62.3%, and the hydroxyl group equivalent was 101 g / e.g.

[0055] Synthesis Example 6 The same procedure as in Synthesis Example 1 was carried out, except that 140.1 g (1.00 mol) of 2-methoxyhydroquinone (structural formula below) was used instead of hydroquinone. 67.0 g of polyhydroxy compound f was obtained. Polyhydroxy compound f was represented by formula (2), where R1 was a methoxy group and R2 to R4 were hydrogen atoms, the number average molecular weight was 200, the total GPC area percentage for n=1 to 3 was 100.0%, and the hydroxyl group equivalent was 93 g / e.g.

[0056] (Synthesis Example 7) 36.4 g (0.20 mol) of syringaldehyde (3,5-dimethoxy-4-hydroxybenzaldehyde, structural formula shown below) was used instead of benzaldehyde. The same procedure as in Synthesis Example 1 was carried out, except that 75.6 g of polyvalent hydroxy compound g was obtained. In the formula (2), polyvalent hydroxy compound g was a compound represented by the formula (2) in which R1 was a hydrogen atom, R2 and R3 were methoxy groups, and R4 was a hydroxy group (OH group), and the compound had a number average molecular weight of 980, a total GPC area percentage of n=1 to 3 of 61.1%, and a hydroxyl group equivalent of 94 g / e.g.

[0057] Example 1 Into a 1000 ml four-neck flask, 27.3 g (0.30 equivalents) of the polyhydric hydroxy compound a obtained in Synthesis Example 1, 500 g of methyl ethyl ketone, and 54.9 g (0.36 equivalents) of 4-(chloromethyl)styrene (structural formula below) were added. The mixture was heated to 60°C, and 20.2 g of potassium hydroxide dissolved in 60.6 g of methanol was added dropwise over 3 hours, followed by a further 6-hour reaction. After completion of the reaction, the mixture was filtered, the solvent was distilled off, and the mixture was reprecipitated with methanol, washed with a large amount of water, and dried under reduced pressure to obtain 50.2 g of a multifunctional vinyl compound (vinyl resin A). The vinyl equivalent of vinyl resin A was 191 g / eg., the hydroxyl equivalent was 18,000 g / eg., the total chlorine was 970 ppm, the Mn was 1,100, and the total GPC area % for n = 1 to 3 was 78.7%.

[0058] Example 2 The same procedure as in Example 1 was carried out, except that 27.9 g (0.30 equivalents) of polyhydric hydroxy compound b obtained in Synthesis Example 2 was used instead of polyhydric hydroxy compound a, to obtain 47.1 g of a polyfunctional vinyl compound (vinyl compound B). Vinyl compound B had a vinyl equivalent of 203 g / e.g., a hydroxyl equivalent of 21,000 g / e.g., a total chlorine content of 700 ppm, a number average molecular weight of 1,020, and a total GPC area percentage of n=1 to 3 of 85.4%.

[0059] Example 3 The same procedure as in Example 1 was carried out, except that 34.5 g (0.30 equivalents) of polyhydric hydroxy compound c obtained in Synthesis Example 3 was used instead of polyhydric hydroxy compound a, to obtain 49.2 g of a polyfunctional vinyl compound (vinyl compound C). Vinyl compound C had a vinyl equivalent of 231 g / e.g., a hydroxyl equivalent of 11,000 g / e.g., a total chlorine content of 800 ppm, a number average molecular weight of 1,500, and a total GPC area percentage of n=1 to 3 of 83.7%.

[0060] Example 4 The same procedure as in Example 1 was carried out, except that 28.5 g (0.30 equivalents) of polyhydric hydroxy compound d obtained in Synthesis Example 4 was used instead of polyhydric hydroxy compound a, to obtain 45.6 g of a polyfunctional vinyl compound (vinyl compound D). Vinyl compound D had a vinyl equivalent of 211 g / e.g., a hydroxyl equivalent of 24,000 g / e.g., a total chlorine content of 850 ppm, a number average molecular weight of 1,320, and a total GPC area percentage of n=1 to 3 of 66.5%.

[0061] Example 5 The same procedure as in Example 1 was carried out, except that 30.3 g (0.30 equivalents) of polyhydric hydroxy compound e obtained in Synthesis Example 5 was used instead of polyhydric hydroxy compound a, to obtain 48.8 g of a polyfunctional vinyl compound (vinyl compound E). Vinyl compound E had a vinyl equivalent of 217 g / e.g., a hydroxyl equivalent of 16,000 g / e.g., a total chlorine content of 730 ppm, a number average molecular weight of 1,220, and a total GPC area percentage of n=1 to 3 of 71.5%.

[0062] Example 6 The same procedure as in Example 1 was carried out, except that 27.9 g (0.30 equivalents) of polyhydric hydroxy compound f obtained in Synthesis Example 6 was used instead of polyhydric hydroxy compound a, to obtain 47.0 g of a polyfunctional vinyl compound (vinyl compound F). Vinyl compound F had a vinyl equivalent of 209 g / e.g., a hydroxyl equivalent of 15,000 g / e.g., a total chlorine content of 630 ppm, a number average molecular weight of 300, and a total GPC area percentage for n=1 to 3 of 100.0%.

[0063] Example 7 The same procedure as in Example 1 was carried out, except that 28.2 g (0.30 equivalents) of polyhydric hydroxy compound g obtained in Synthesis Example 7 was used instead of polyhydric hydroxy compound a, to obtain 47.8 g of a polyfunctional vinyl compound (vinyl compound G). Vinyl compound G had a vinyl equivalent of 210 g / e.g., a hydroxyl equivalent of 13,000 g / e.g., a total chlorine content of 830 ppm, a number average molecular weight of 1,530, and a total GPC area percentage of n=1 to 3 of 74.5%.

[0064] Comparative Example 1 Into a 1000 ml four-neck flask, 40.8 g of 4,4'-bis(chloromethyl)biphenyl (structural formula below) 75.5 g of 4,4'-biphenol (structural formula below), 120 g of diethylene glycol dimethyl ether was charged, and the mixture was heated to 160 ° C. under a nitrogen stream while stirring and reacted for 10 hours. Subsequently, the temperature was raised to 70 ° C., and 280 g of diethylene glycol dimethyl ether and 129.5 g of chloromethylstyrene were added. 100.0 g of 48% potassium hydroxide was added dropwise to the mixture. Gas chromatography confirmed that there was no residual chloromethylstyrene, and the solvent was recovered under reduced pressure. The resulting resin was dissolved in toluene, neutralized, and washed with water to obtain 172 g of a multifunctional vinyl resin (vinyl resin H). The vinyl equivalent of the resulting vinyl resin H was 256 g / eq., the hydroxyl equivalent was 1500 g / eq., and the total chlorine was 1270 ppm.

[0065] Comparative Example 2: 30.6 g (0.30 equivalents) of 1,1,1-tris(p-hydroxyphenyl)ethane (structural formula below) was used in place of polyhydric hydroxy compound a. The same procedure as in Example 1 was carried out except that 58.9 g of a vinyl compound (vinyl compound I) was obtained. The vinyl equivalent of vinyl compound I was 214 g / eg., the hydroxyl equivalent was 7000 g / eg., and the total chlorine content was 1500 ppm.

[0066] (Comparative Example 3) Into a 1000 ml four-neck flask, 50.0 g of dihydroxydiphenylmethane (4,4'-dihydroxydiphenylmethane (structural formula below): 36.2%, 2,4'-dihydroxydiphenylmethane: 46.6%, 2,2'-dihydroxydiphenylmethane: 17.2%), 400 g of methyl ethyl ketone and 80.1 g of chloromethylstyrene were added, and the mixture was heated to 60°C. 29.5 g of potassium hydroxide dissolved in 88 g of methanol was added dropwise over 3 hours, and the reaction was continued for an additional 6 hours. After the reaction was completed, the mixture was filtered, the solvent was distilled off, and the mixture was reprecipitated with methanol, washed with a large amount of water, and dried under reduced pressure to obtain 95.4 g of a vinyl compound (vinyl compound J). The vinyl equivalent of vinyl compound J was 217 g / eg., the hydroxyl equivalent was 17,000 g / eg., and the total chlorine content was 400 ppm.

[0067] Examples 8-14, Comparative Examples 4-7: As the polyfunctional vinyl compound, vinyl compounds A to J obtained in Examples 1-5 and Comparative Examples 1-3 and vinyl resin K (OPE-2ST: manufactured by Mitsubishi Gas Chemical Company, Inc., vinyl group equivalent: 590.0 g / eq, number average molecular weight 1187) were used. Perbutyl P (manufactured by NOF Corporation), an organic peroxide, was used as the radical polymerization initiator, and Adeka Stab AO-60 (manufactured by ADEKA Corporation) was used as the antioxidant. These were mixed in the proportions shown in Table 1 and dissolved in a solvent to form a homogeneous composition. This composition was applied to a PET film and dried at 130°C for 5 minutes to obtain a resin composition. The composition removed from the PET film was sandwiched between mirror plates and cured under reduced pressure at 130°C for 15 minutes and at 210°C for 80 minutes while applying a pressure of 2 MPa. The properties of the resulting cured product are shown in Table 1.

[0068]

[0069] The polyfunctional vinyl compounds of the Examples exhibited excellent physical properties such as high thermal conductivity, low dielectric constant and low dielectric loss tangent, as compared with the Comparative Examples.

[0070] The polyfunctional vinyl compound of the present invention is useful as an electronic material for high-speed communication devices, as it allows heat generated from electronic components and wiring to escape easily and causes little signal loss.

Claims

1. A polyfunctional vinyl compound represented by the following general formula (1): In formula (1), R1 independently represents a hydrogen atom, a fluorine atom, a methoxy group, or a monovalent hydrocarbon group having 1 to 6 carbon atoms. R2 to R4 independently represent a hydrogen atom, a hydroxy group, a fluorine atom, a methoxy group, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a vinylbenzyl ether group. n represents a number from 1 to 15.

2. The polyfunctional vinyl compound according to claim 1, wherein the total content of n=1 to 3 in terms of GPC area % is 60% or more.

3. A polyfunctional vinyl composition comprising, as essential components, the vinyl compound according to claim 1 or 2 and a radical polymerization initiator.

4. A cured polyfunctional vinyl product obtained by curing the polyfunctional vinyl composition according to claim 3.

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