Thermosetting composition and method for producing cured product

Abstract

To provide a thermosetting composition excellent in thermosetting property at a relatively low temperature (for example, 100 °C or lower).SOLUTION: The thermosetting composition comprises an epoxy resin, at least one curing agent selected from the group consisting of an acid anhydride-based curing agent, a phenol-based curing agent and a thiol-based curing agent, and a zeolite-like imidazolate structure.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a thermosetting composition containing an epoxy resin and a method for producing a cured product. [Background technology]

[0002] Thermosetting compositions containing epoxy resins are used in various fields, including the bonding of electronic components, and therefore have been actively studied, and various techniques have been proposed.

[0003] For example, Patent Document 1 discloses a composition containing an epoxy resin and a curing accelerator obtained by intercalating an amine into a layered compound. Patent Document 2 discloses a resin composition containing an organometallic complex (e.g., ZIF-7, a type of zeolite-like imidazolate structure) and a curable resin (e.g., epoxy resin), in which the content of the organometallic complex in the resin composition is 5% by weight or more. Non-Patent Document 1 discloses the use of ZIF-8, a type of zeolite-like imidazolate structure, as a curing agent for epoxy resins (more specifically, a catalytic curing agent that catalyzes the addition reaction between epoxy resins). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-101397 [Patent Document 2] Japanese Patent Application Publication No. 2018-80327 [Non-patent literature]

[0005] [Non-Patent Document 1] Liu, C.; et al. ACS Appl. Mater. Interfaces, 2018, 10, 1250-1257 Summary of the Invention [Problem to be solved by the invention]

[0006] For example, when a thermosetting composition is used to bond electronic components, it is required that the thermosetting composition be well thermoset at a relatively low temperature (i.e., that the thermosetting composition have excellent thermosetting properties at a relatively low temperature) in order to reduce the thermal impact on the electronic components. The present invention has been made in light of such circumstances, and an object of the present invention is to provide a thermosetting composition that has excellent thermosetting properties at a relatively low temperature (e.g., 100°C or lower). [Means for solving the problem]

[0007] As a result of extensive research, the present inventors have found that a thermosetting composition having excellent thermosetting properties at relatively low temperatures can be obtained by using a zeolite-like imidazolate structure as at least one curing agent selected from the group consisting of acid anhydride curing agents, phenolic curing agents, and thiol curing agents, and as a curing accelerator for an epoxy resin.

[0008] Patent Document 2 discloses the use of an organometallic complex to obtain a low dielectric tangent, and discloses the use of a zeolite-like imidazolate structure as the organometallic complex. However, Patent Document 2 does not disclose the use of a zeolite-like imidazolate structure as a curing accelerator. Specifically, Example 9 of Patent Document 2 discloses a thermosetting composition containing a large amount of ZIF-7 (specifically, 10 wt.% of the total thermosetting composition), but in addition to ZIF-7, a curing accelerator ("EMI24" manufactured by Japan Epoxy Resins Co., Ltd.) is used in the composition. Furthermore, Non-Patent Document 1 discloses the use of ZIF-8 as a curing agent for epoxy resins (specifically, a catalytic curing agent), but does not disclose the use of ZIF-8 as a curing accelerator that promotes the addition reaction between an epoxy resin and a curing agent (specifically, an addition-type curing agent capable of addition reaction with an epoxy resin). Specifically, Non-Patent Document 1 does not disclose a thermosetting composition containing an epoxy resin, ZIF-8, and a curing agent other than ZIF-8 (for example, an acid anhydride-based curing agent).

[0009] The present invention based on the above findings is as follows. [1] Epoxy resin, At least one curing agent selected from the group consisting of an acid anhydride curing agent, a phenolic curing agent, and a thiol curing agent; and Zeolite-like imidazolate structures A thermosetting composition comprising: [2] The thermosetting composition according to [1], wherein the zeolite-like imidazolate structure is at least one selected from the group consisting of ZIF-1, ZIF-2, ZIF-3, ZIF-4, ZIF-5, ZIF-6, ZIF-7, ZIF-8, ZIF-9, ZIF-10, ZIF-11, ZIF-12 and ZIF-14. [3] The thermosetting composition according to [1] or [2], wherein the thermosetting composition contains an acid anhydride curing agent. [4] The thermosetting composition according to [1] or [2], wherein the thermosetting composition contains a thiol-based curing agent. [5] A method for producing a cured product by heating the thermosetting composition according to any one of [1] to [4] above, wherein the heating temperature of the thermosetting composition is 100°C or lower. [6] The thermosetting composition according to any one of [1] to [4] above, which is used in the production of electronic or optical components. [Effects of the Invention]

[0010] According to the present invention, which uses a zeolite-like imidazolate structure as a curing accelerator, a thermosetting composition having excellent thermosetting properties at relatively low temperatures (for example, 100° C. or less) can be obtained. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a scanning electron microscope (SEM) image of ZIF-8 obtained in Synthesis Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Zeolite-like imidazolate structure> One of the features of the present invention is the use of a zeolite-like imidazolate structure as a curing accelerator. Here, the zeolite-like imidazolate structure (sometimes abbreviated as "ZIF" in this specification) refers to a metal-organic framework having a zeolite-like three-dimensional shape formed by the assembly of at least one selected from the group consisting of zinc ions, cobalt ions, cadmium ions, lithium ions, manganese ions, mercury ions, iron ions, copper ions, and indium ions and imidazole-based ligands. Furthermore, in this invention, the curing accelerator refers to an additive that promotes the addition reaction between an epoxy resin and a curing agent (specifically, an addition-type curing agent).

[0013] By using ZIF, it is possible to obtain a thermosetting composition that has excellent thermosetting properties at relatively low temperatures (for example, 100°C or less). Furthermore, as shown in Example 1 and Comparative Example 1 described later, when the curing accelerator described in Patent Document 1 (specifically, a curing accelerator obtained by intercalating an amine into a layered compound) is used, a cloudy cured product is obtained, but by using ZIF, a transparent cured product can be obtained.

[0014] ZIF may be used alone or in combination of two or more. The curing accelerator in the thermosetting composition of the present invention is preferably ZIF. ZIF can be produced by a known method as shown in the synthesis example below.

[0015] Specific examples of ZIF include ZIF-1 to ZIF-12 and ZIF-14 listed in Table 1 below. ZIF is preferably at least one selected from the group consisting of ZIF-1 to ZIF-12 and ZIF-14, more preferably at least one selected from the group consisting of ZIF-7, ZIF-8, ZIF-11 and ZIF-14, and from the viewpoint of thermosetting at relatively low temperatures, more preferably ZIF-8 and / or ZIF-14.

[0016] [Table 1]

[0017] If ZIF is used in large amounts, the physical properties of the resulting cured product may be reduced. In order to prevent this reduction in physical properties, the content of ZIF is necessary or preferable to be 3% by weight or less, preferably 2% by weight or less, based on the total thermosetting composition. On the other hand, in terms of thermosetting at relatively low temperatures, it is preferably 0.3% by weight or more, more preferably 1% by weight or more.

[0018] The average particle size of ZIF is preferably 10 nm to 10 μm, more preferably 50 nm to 5 μm. As described in the following Examples, this average particle size can be calculated by randomly selecting five particles in a scanning electron microscope (SEM) image of ZIF, measuring their maximum diameters, and averaging the five maximum diameters obtained.

[0019] <Epoxy resin> One of the features of the thermosetting composition of the present invention is that it contains an epoxy resin. The epoxy resin may be used alone or in combination of two or more kinds.

[0020] In the present invention, epoxy resin refers to a thermosetting resin having epoxy groups. In other words, epoxy resin refers to a compound having two or more epoxy groups in one molecule and capable of being thermoset. The epoxy resin may be a monomer (i.e., a monomer-type epoxy resin) or a polymer having multiple repeating units. The epoxy equivalent of the epoxy resin is preferably 80 to 6,000 g / eq, more preferably 90 to 5,000 g / eq, and even more preferably 100 to 3,000 g / eq. Here, epoxy equivalent refers to the number of grams of a compound containing 1 gram equivalent of epoxy groups (unit: g / eq). In other words, epoxy equivalent refers to the value obtained by dividing the molecular weight of a compound containing epoxy groups by the number of epoxy groups contained in the compound, i.e., the molecular weight per epoxy group.

[0021] In the present invention, the epoxy resin is not particularly limited, and any known epoxy resin can be used. Examples of epoxy resins include bisphenol A type epoxy resins (e.g., bisphenol A diglycidyl ether), bisphenol AD ​​type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, resorcinol type epoxy resins, dihydroxynaphthalene type epoxy resins, biphenyl type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, triphenylmethane type epoxy resins, tetraphenylethane type epoxy resins, dicyclopentadiene type epoxy resins, phenol aralkyl type epoxy resins, brominated phenol novolac type epoxy resins, naphthol novolac type epoxy resins, naphthol aralkyl type epoxy resins, aliphatic ether type epoxy resins obtained by glycidylating polyhydric alcohols such as glycerin and polyethylene glycol, ether ester type epoxy resins obtained by glycidylating hydroxycarboxylic acids such as p-oxybenzoic acid and β-oxynaphthoic acid, and ester type epoxy resins obtained by glycidylating polycarboxylic acids such as phthalic acid and terephthalic acid. The epoxy resin is preferably a bisphenol A type epoxy resin.

[0022] <Curing agent> One of the features of the thermosetting composition of the present invention is that it contains at least one curing agent selected from the group consisting of acid anhydride curing agents, phenolic curing agents, and thiol curing agents. The acid anhydride curing agents, phenolic curing agents, and thiol curing agents may each be used alone or in combination of two or more. The curing agent in the thermosetting composition of the present invention is preferably at least one selected from the group consisting of acid anhydride curing agents, phenolic curing agents, and thiol curing agents.

[0023] In the present invention, the acid anhydride curing agent is not particularly limited, and known acid anhydride curing agents can be used. Examples of acid anhydride curing agents include trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride (e.g., 4-methylhexahydrophthalic anhydride), methylnadic anhydride, and 3,3',4,4'-benzophenonetetracarboxylic dianhydride.

[0024] In the present invention, the phenolic curing agent is not particularly limited, and known phenolic curing agents can be used. Examples of phenolic curing agents include bisphenol A, bisphenol F, bisphenol S, resorcinol, catechol, hydroquinone, fluorene bisphenol, 4,4'-biphenol, 4,4',4"-trihydroxytriphenylmethane, naphthalenediol, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, phenol novolac resin, cresol novolac resin, dicyclopentadiene-type phenolic resin, phenol aralkyl resin, resorcinol novolac resin, naphthol aralkyl resin, trimethylolmethane resin, tetraphenylolethane resin, and naphthol novolac resin.

[0025] In the present invention, the thiol-based curing agent is not particularly limited, and known thiol-based curing agents can be used. Examples of thiol-based curing agents include trimethylolpropane tris(3-mercaptopropionate), tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, pentaerythritol tetrakis(3-mercaptopropionate), tetraethylene glycol bis(3-mercaptopropionate), dipentaerythritol hexakis(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), and 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione.

[0026] From the viewpoint of storage stability of the thermosetting composition, an acid anhydride-based curing agent is preferred. That is, from the viewpoint of storage stability, the thermosetting composition of the present invention preferably contains an acid anhydride-based curing agent, and more preferably, the curing agent in the thermosetting composition of the present invention consists of an acid anhydride-based curing agent.

[0027] From the viewpoint of the thermosetting property of the thermosetting composition at a relatively low temperature, a thiol-based curing agent is preferred. That is, from the viewpoint of the thermosetting property at a relatively low temperature, the thermosetting composition of the present invention preferably contains a thiol-based curing agent, and more preferably, the curing agent in the thermosetting composition of the present invention consists of a thiol-based curing agent.

[0028] The amounts of the curing agent and epoxy resin used in the thermosetting composition of the present invention are determined by the molar ratio of the reactive functional groups in the curing agent to the epoxy groups in the epoxy resin. Specifically, the molar ratio of the sum of the amount of acid anhydride groups (i.e., carbonyloxycarbonyl groups (-CO-O-CO-)), the amount of sulfanyl groups (-SH), and the amount of phenolic hydroxyl groups to the amount of epoxy groups (i.e., "(amount of acid anhydride groups (mol) + amount of sulfanyl groups (mol) + amount of phenolic hydroxyl groups (mol)) / (amount of epoxy groups (mol))" is preferably 0.5 to 1.2, and more preferably 0.7 to 1.1. Note that, for example, when only an acid anhydride curing agent is used as the curing agent, "the sum of the amount of acid anhydride groups, the amount of sulfanyl groups, and the amount of phenolic hydroxyl groups" = "the amount of acid anhydride groups," when only a thiol curing agent is used as the curing agent, "the sum of the amount of acid anhydride groups, the amount of sulfanyl groups, and the amount of phenolic hydroxyl groups" = "the amount of sulfanyl groups," and when only a phenolic curing agent is used as the curing agent, "the sum of the amount of acid anhydride groups, the amount of sulfanyl groups, and the amount of phenolic hydroxyl groups" = "the amount of phenolic hydroxyl groups."

[0029] <Other additives> The thermosetting composition of the present invention may contain additives other than the above-described ZIF, epoxy resin, and curing agent (for example, additives known in the field of epoxy resins) within the range that does not impair the effects of the present invention.

[0030] <Method of manufacturing the cured product> The present invention also provides a method for producing a cured product by heating the above-mentioned thermosetting composition. The production method of the present invention is characterized in that the above-mentioned thermosetting composition is heated to a temperature of 100°C or less. Here, "the thermosetting composition is heated to a temperature of 100°C or less" means that the thermosetting composition is not heated to a temperature exceeding 100°C. For example, Example 9 of Patent Document 2 describes a method for producing a cured product by heat-curing the thermosetting composition by holding it at 80°C for 3 hours and then at 120°C for 6 hours. However, because the method involves heating at 120°C, it does not satisfy the requirement that "the thermosetting composition is heated to a temperature of 100°C or less."

[0031] The thermosetting composition of the present invention is preferably used in the production (particularly, adhesion) of electronic components, optical components, etc. In order to avoid thermal effects on electronic components, the heating temperature of the thermosetting composition is 100°C or lower, preferably 95°C or lower. In addition, from the viewpoint of obtaining a good cured product (specifically, a well-cured product), the heating temperature of the thermosetting composition is preferably 60°C or higher, more preferably 80°C or higher. The heating time of the thermosetting composition is preferably 0.1 to 10 hours, more preferably 0.5 to 3 hours. The thermosetting composition may be heated in air, in an inert gas (e.g., nitrogen gas) atmosphere, or under reduced pressure. The thermosetting composition can be heated using known equipment, such as an oven.

[0032] Before curing the thermosetting composition at the above heating temperature for the above heating time, the thermosetting composition may be preheated (precured) at a temperature lower than the above heating temperature. The preheating temperature of the thermosetting composition is preferably 60 to 95°C, more preferably 80 to 90°C. The preheating time of the thermosetting composition is preferably 0.1 to 3 hours, more preferably 0.3 to 1 hour. [Example]

[0033] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and can be implemented with appropriate modifications within the scope of the above and below spirit, and all such modifications are included in the technical scope of the present invention.

[0034] Synthesis Example 1: Synthesis of ZIF-8

[0035] [ka]

[0036] ZIF-8 was synthesized according to the method described in M. Sadakiyo, H. Kasai, K. Kato, M. Takata, and M. Yamauchi. J Am Chem Soc 2014, 136, 1702–1705. Specifically, 2-methylimidazole (16.42 g, 200 mmol) dissolved in 500 mL of methanol was added to a solution of Zn(NO3)2·6H2O (14.87 g, 50 mmol) in 500 mL of methanol and allowed to stand at room temperature for 48 hours. After standing, the mixture was centrifuged at 9500 rpm for 5 minutes. The resulting white powder was washed by suspending it in methanol and centrifuging it at 9500 rpm for 5 minutes three times. The powder was then dried overnight under reduced pressure to obtain ZIF-8 (3.55 g, 31% yield).

[0037] Synthesis Example 2: Synthesis of ZIF-14

[0038] [ka]

[0039] ZIF-14 was synthesized according to the method described in S. Bhattacharyya, R. Han, W.-G. Kim, Y. Chiang, KC Jayachandrababu, JT Hungerford, MR Dutzer, C. Ma, KS Walton, DS Sholl, and S. Nair. Chemistry of Materials 2018, 30, 4089-4101. Specifically, 2-ethylimidazole (1.92 g, 20 mmol) dissolved in water (50 mL) was added to a solution of Zn(NO3)2·6H2O (1.49 g, 5.0 mmol) in 1-octanol (50 mL) and stirred at room temperature for 2.5 hours. After stirring, the mixture was centrifuged (9500 rpm, 5 min) for solid-liquid separation. The resulting white powder was suspended in methanol and then centrifuged (9500 rpm, 5 min) three times for washing. The powder was then dried overnight at 60 °C under reduced pressure to obtain ZIF-14 (yield: 0.61 g, 47%).

[0040] Synthesis Example 3: Synthesis of ZIF-7

[0041] [ka]

[0042] ZIF-7 was synthesized according to the method described in C. Adhikari, A. Das, and A. Chakraborty, Molecular pharmaceutics 2015, 12, 3158-3166. Specifically, Zn(NO3)2·6H2O (3.00 g, 10 mmol), benzimidazole (10.00 g, 85 mmol), and N,N-dimethylformamide (DMF) (100 mL) were added to a reactor and stirred at room temperature for 48 h. After stirring, the mixture was centrifuged at 9500 rpm for 5 min. The resulting white powder was washed five times by suspending it in DMF and centrifuging it at 9500 rpm for 5 min. The powder was then dried overnight at 100 °C under reduced pressure to obtain ZIF-7 (1.48 g, 49%).

[0043] Synthesis Example 4: Synthesis of ZIF-11

[0044] [ka]

[0045] ZIF-11 was synthesized according to the method described in V. Armel, S. Hindocha, F. Salles, S. Bennett, D. Jones, and F. Jaouen. J Am Chem Soc 2017, 139, 453-464. Specifically, benzimidazole (0.76 g, 6.4 mmol) was dissolved in a mixture of methanol (45 mL) and toluene (30 mL). To the resulting solution, 0.89 mL of aqueous ammonia was added, followed by 0.70 g of Zn(OAc)2·2H2O (0.70 g, 3.2 mmol). The resulting mixture was stirred at room temperature for 3 h. After stirring, the mixture was centrifuged at 9500 rpm for 5 min. The resulting white powder was washed three times by suspending it in ethanol and centrifuging it at 9500 rpm for 5 min. The powder was then dried overnight under reduced pressure to obtain ZIF-11 (0.96 g, 99% yield).

[0046] Scanning electron microscope (SEM) images of the ZIF-8 synthesized as described above were measured using a JEOL JSM-840 scanning electron microscope at an accelerating voltage of 15 kV. As a representative SEM image, the SEM image of ZIF-8 obtained in Synthesis Example 1 is shown in Figure 1.

[0047] Five particles were randomly selected from the SEM images, their maximum diameters were measured, and the average particle size was calculated by averaging the five maximum diameters. As a result, the average particle size of ZIF-8 was 280 nm, that of ZIF-14 was 2.1 μm, that of ZIF-7 was 75 nm, and that of ZIF-11 was 6.5 μm.

[0048] Experimental Example 1 The function of ZIF-8 as a catalytic curing agent was investigated using glycidyl phenyl ether (hereinafter sometimes abbreviated as "GPE"), a monofunctional epoxy compound, instead of epoxy resin.

[0049] [ka]

[0050] Specifically, a composition was prepared by mixing GPE (151 mg, 1.00 mmol) and ZIF-8 (3.4 mg, 0.015 mmol). The resulting composition was heated at 80 °C for 1 hour. A small sample of the heated composition was dissolved in CDCl3 and 1 The conversion rate of GPE was calculated by H NMR measurement. 1 H NMR measurements were performed using a JEOL JNM-ECZS Fourier transform magnetic resonance spectrometer (400 MHz) with tetramethylsilane as the internal standard. The same applies below. The conversion rate of GPE was calculated using the same procedure except that the heating temperature was changed to 100°C, 120°C, or 140°C. The results confirmed that the polymerization reaction of GPE did not proceed even when the heating temperature was increased to 140°C.

[0051] From the results of Experimental Example 1 using GPE, a monofunctional epoxy compound, it is thought that a composition containing an epoxy resin and ZIF-8, but not containing a curing agent other than ZIF-8, will not be sufficiently cured even when heated to 140 ° C.

[0052] Experimental Example 2 Instead of epoxy resin, we used GPE, a monofunctional epoxy compound, and 4-methylhexahydrophthalic anhydride (hereinafter sometimes abbreviated as "MHHPA"), an acid anhydride curing agent, to investigate its function as a curing accelerator for ZIF-8 and other compounds.

[0053] [ka]

[0054] Specifically, GPE (150 mg, 1.00 mmol), MHHPA (167 mg, 1.00 mmol), and ZIF-8 (3.4 mg, 0.015 mmol) were mixed to prepare a composition (ZIF-8 content relative to the total composition: 1.1 wt%). The resulting composition was heated at 60 °C for 1 hour. A small sample of the heated composition was dissolved in CDCl3 and 1 The conversion rate of GPE was calculated by H NMR measurement. The same procedure was performed except that the heating temperature was changed to 80°C, 90°C, 100°C, or 120°C. The results are shown in Table 2.

[0055] Instead of ZIF-8 (3.4 mg), ZIF-14 (3.9 mg), a hardening accelerator obtained by intercalating 2-methylimidazole into α-zirconium phosphate (hereinafter sometimes abbreviated as "α-ZrP·2MIm") (11.7 mg) described in Patent Document 1, and "Novacure", a hardening accelerator manufactured by Asahi Kasei Corporation, were used. TM HX-3088 (sometimes abbreviated as "HX-3088" in this specification) (10 mg) or "Novacure" (a curing accelerator manufactured by Asahi Kasei Corporation) TM The conversion rate of GPE was calculated in the same manner as above, except that 10 mg of PEG-3722 (sometimes abbreviated as "HX-3722" in this specification) was used. The results are shown in Table 2.

[0056] [Table 2]

[0057] As shown in Table 2, when ZIF-8 was used, the GPE conversion increased when the heating temperature exceeded 80°C. At 100°C for 1 hour, the GPE conversion was 92%. At 100°C for 1 hour, the GPE conversion was 93% when ZIF-14 was used. On the other hand, at 100°C for 1 hour, the GPE conversion was 66% when HX-3088 was used, 75% when HX-3722 was used, and 67% when α-ZrP·2MIm was used.

[0058] Experimental Example 3 Compositions were prepared in the same manner as in Experimental Example 2 using GPE, a monofunctional epoxy compound, MHHPA, an acid anhydride curing agent, and ZIF-8, HX-3088, or HX-3722. The resulting compositions were heated at 90°C for up to 3 hours, and the conversion of GPE was calculated in the same manner as in Experimental Example 2 when the heating time was 1, 2, or 3 hours. The results are shown in Table 3.

[0059] [Table 3]

[0060] As shown in Table 3, when ZIF-8 was used, the conversion of GPE was 94% when heated at 90°C for 3 hours.

[0061] From the results of Experimental Examples 2 and 3 using GPE, a monofunctional epoxy compound, it is considered that the thermosetting composition containing an epoxy resin, an acid anhydride curing agent, and ZIF-8 can be sufficiently cured even when heated at a relatively low temperature (90 to 100°C), that is, the thermosetting composition has excellent thermosetting properties at a relatively low temperature.

[0062] Experimental Example 4 Compositions were prepared in the same manner as in Experimental Example 2 using GPE, a monofunctional epoxy compound, MHHPA, an acid anhydride curing agent, and ZIF-8 or ZIF-14. The resulting compositions were stored at 25°C, and the conversion rate of GPE was calculated in the same manner as in Experimental Example 2. The results are shown in Table 4.

[0063] [Table 4]

[0064] As shown in Table 4, when the storage temperature was 25 ° C, even after 8 days of storage, the GPE conversion rate of the composition containing ZIF-8 was 11%, and the GPE conversion rate of the composition containing ZIF-14 was 12%. From the results of Experimental Example 4 using GPE, a monofunctional epoxy compound, it is considered that when a thermosetting composition containing an epoxy resin, an acid anhydride curing agent, and ZIF-8 or ZIF-14 is stored at 25 ° C, the reaction of the epoxy resin is suppressed and the storage stability is excellent.

[0065] Experimental Example 5 Instead of epoxy resin, we used GPE, a monofunctional epoxy compound, and pentaerythritol tetrakis(3-mercaptopropionate) (hereinafter sometimes abbreviated as "PETMP"), a thiol-based curing agent, to investigate their function as curing accelerators for ZIF-8 and other compounds.

[0066] [ka]

[0067] Specifically, GPE (150 mg, 1.00 mmol), PETMP (123 mg, 0.25 mmol), and ZIF-8 (3.4 mg, 0.015 mmol) were mixed to prepare a composition (ZIF-8 content relative to the total composition: 1.2 wt%). The resulting composition was heated at 40 °C for 1 hour. A small sample of the heated composition was dissolved in CDCl3 and 1 The conversion rate of GPE was calculated by H NMR measurement. The same procedure was performed except that the heating temperature was changed to 60°C or 80°C, and the conversion rate of GPE was calculated. The results are shown in Table 5.

[0068] The conversion of GPE was calculated in the same manner as above, except that ZIF-7 (4.5 mg), ZIF-11 (4.4 mg), or ZIF-14 (4.0 mg) was used instead of ZIF-8 (3.4 mg). The results are shown in Table 5.

[0069] [Table 5]

[0070] From the results of Experimental Example 5 using GPE, a monofunctional epoxy compound, shown in Table 5, it can be seen that the thermosetting composition containing an epoxy resin, a thiol-based curing agent, ZIF-8, etc. can be sufficiently cured even when heated at a relatively low temperature (80°C), i.e., the thermosetting composition is considered to have excellent thermosetting properties at a relatively low temperature.

[0071] Experimental Example 6 The monofunctional epoxy compound GPE was used instead of epoxy resin, and phenol was used instead of phenolic curing agents to investigate their function as curing accelerators for ZIF-8 and other compounds.

[0072] [ka]

[0073] Specifically, GPE (152 mg, 1.01 mmol), phenol (94 mg, 0.100 mmol), and ZIF-8 (3.4 mg, 0.015 mmol) were mixed to prepare a composition (ZIF-8 content relative to the total composition: 1.4 wt%). The resulting composition was heated at 60 °C for 1 hour. A small sample of the heated composition was dissolved in CDCl3 and 1 The conversion rate of GPE was calculated by H NMR measurement. The same procedure was performed except that the heating temperature was changed to 80°C, 100°C, or 120°C, and the conversion rate of GPE was calculated. The results are shown in Table 6.

[0074] The conversion rate of GPE was calculated in the same manner as above, except that ZIF-14 (3.8 mg) was used instead of ZIF-8 (3.4 mg). The results are shown in Table 6.

[0075] [Table 6]

[0076] As shown in Table 6, when ZIF-8 or ZIF-14 was used, the conversion of GPE increased when the heating temperature exceeded 80°C. At 100°C and 1 hour of heating, the conversion of GPE was 81% when ZIF-8 was used and 95% when ZIF-14 was used.

[0077] From the results of Experimental Example 6 using the monofunctional epoxy compound GPE and phenol, it is considered that the thermosetting composition containing the epoxy resin, the phenolic curing agent, and ZIF-8 etc. can be sufficiently cured even when heated at a relatively low temperature (100°C), that is, the thermosetting composition has excellent thermosetting properties at a relatively low temperature.

[0078] Example 1 and Comparative Example 1 A thermosetting composition containing the epoxy resin bisphenol A diglycidyl ether (hereinafter sometimes abbreviated as "DGEBA"), the acid anhydride curing agent MHHPA, and the curing accelerator ZIF-8 (Example 1) or α-ZrP·2MIm (Comparative Example 1) described in Patent Document 1 was prepared and thermally cured to obtain a cured product.

[0079] [ka]

[0080] Specifically, DGEBA (344 mg, 1.01 mmol), MHHPA (336 mg, 2.00 mmol), ZIF-8 (6.8 mg, 0.030 mmol; 2-methylimidazole content in ZIF-8: 0.060 mmol, Example 1) or α-ZrP·2MIm (24.0 mg, 0.064 mmol; 2-methylimidazole content in α-ZrP·2MIm: 0.057 mmol, Comparative Example 2) were mixed to prepare a thermosetting composition (ZIF-8 content: 1.0 wt% in Example 1, and α-ZrP·2MIm content: 3.6 wt% in Comparative Example 1). The resulting thermosetting composition was heated and stirred in an oil bath set to 90°C for 30 minutes. The thermosetting composition was then sprayed with a fluorine-based release agent, and poured onto a glass slide frame (4 cm long, 5 mm wide) made with tape. The composition was then degassed by reducing the pressure in a desiccator at room temperature for 3 minutes, closing the valve, and leaving it to stand for 1 hour. The degassed thermosetting composition was heated in an oven set to 100°C for 1 hour to prepare a cured product.

[0081] The thermosetting composition of Example 1, which used ZIF-8, was able to form a tack-free cured product even when heated at a relatively low temperature (maximum 100°C), demonstrating excellent thermosetting properties at relatively low temperatures. Furthermore, the thermosetting composition of Example 1, which used ZIF-8, yielded a transparent cured product, whereas the thermosetting composition of Comparative Example 1, which used α-ZrP·2MIm, yielded a cured product that was cloudy compared to the cured product of Example 1. [Industrial Applicability]

[0082] The thermosetting composition of the present invention has excellent thermosetting properties at relatively low temperatures and is therefore useful for, for example, bonding electronic components.

Claims

1. epoxy resin, At least one curing agent selected from the group consisting of an acid anhydride curing agent and a thiol curing agent; and Zeolite-like imidazolate structures A thermosetting composition comprising:

2. The thermosetting composition according to claim 1, wherein the zeolite-like imidazolate structure is at least one selected from the group consisting of ZIF-1, ZIF-2, ZIF-3, ZIF-4, ZIF-5, ZIF-6, ZIF-7, ZIF-8, ZIF-9, ZIF-10, ZIF-11, ZIF-12 and ZIF-14.

3. The thermosetting composition according to claim 1 or 2, wherein the thermosetting composition contains an acid anhydride curing agent.

4. The thermosetting composition according to claim 1 or 2, wherein the thermosetting composition contains a thiol-based curing agent.

5. A method for producing a cured product by heating the thermosetting composition according to any one of claims 1 to 4, wherein the heating temperature of the thermosetting composition is 100°C or less.

6. The thermosetting composition according to any one of claims 1 to 4, which is used in the production of electronic or optical components.

Images