Composite material, application product thereof, and method for manufacturing composite material

Abstract

To improve chemical stability of a material containing a metal organic structure.SOLUTION: A composite material includes a metal organic structure, and a silicon-containing polymer. The metal organic structure includes a zeolite-like imidazolate structure. The silicon-containing polymer includes a principal chain having at least one selected from a group comprising a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit. The silicon-containing polymer has a functional group shown as -SiR3-n(OX)n, for example. n represents an integer from 1-3, and X represents a binding site with a hydrogen atom, a 1-10C hydrocarbon group, and the metal organic structure, or a binding site with a silicon atom other than the silicon atom in the functional group. At least one X is the binding site with the metal organic structure. R represents a 1-10C hydrocarbon group.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to composite materials, their applications, and methods for manufacturing composite materials. [Background technology]

[0002] Patent Document 1 describes a resin composition for forming an insulating film, which contains a metal-organic framework and a curable resin. Patent Document 2 describes an organosilicon compound used in a rubber composition. Non-Patent Documents 1, 2, and 3 disclose methods for chemically modifying the surface of a metal-organic framework. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-80327 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-191040 [Non-patent literature]

[0004] [Non-Patent Document 1] Shuliang Yang, Li Peng, Daniel T. Sun, Mehrdad Asgari, Emad Oveisi, Olga Trukhina, Safak Bulut, Abbas Jamalia and Wendy L. Queen, Chem. Sci., 2019, vol. 10, 4542-4549 [Non-patent document 2] Sanfeng He, Hongliang Wang, Cuizheng Zhang, Songwei Zhang, Yi Yu, Yongjin Lee and Tao Li, Chem. Sci., 2019, vol. 10, 1816-1822 [Non-patent document 3] Yuxiu Sun, Qi Sun, Hongliang Huang, Briana Aguila, Zheng Niu, Jason A. Perman and Shengqian Ma, J. Mater. Chem., 2017, vol. 5, 18770-18776 [Non-patent document 4] Anoopa Thomas, Rafiq Ahamed and Muthuramalingam Prakash, RSC Adv., 2020, vol. 10, 39160-39170 [Non-Patent Document 5] Fangyuan Tian, Andrew M. Cerro, Amber M. Mosier, Hannah K. Wayment-Steele, Ryan S. Shine, Aileen Park, Elizabeth R. Webster, Lewis E. Johnson, Malkiat S. Johal and Lauren Benz, J. Phys. Chem., 2014, vol. 118, 14449-14456 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure aims to improve the chemical stability of materials that include metal-organic frameworks. [Means for solving the problem]

[0006] The composite material of the present disclosure comprises: a metal-organic framework; a silicon-containing polymer; the metal organic framework comprises a zeolite-like imidazolate framework; The silicon-containing polymer comprises a main chain having at least one selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to improve the chemical stability of materials including metal-organic frameworks. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a composite material according to the first embodiment. [Figure 2] FIG. 2 is a flowchart showing an example of a method for producing a composite material according to the first embodiment. [Figure 3] FIG. 3 is a diagram showing a schematic configuration of a resin composition according to the third embodiment. [Figure 4] FIG. 4 is a cross-sectional view of a resin-coated film according to the fifth embodiment. [Figure 5] FIG. 5 is a cross-sectional view of a resin-coated metal foil according to the sixth embodiment. [Figure 6] FIG. 6 is a cross-sectional view of a metal-clad laminate according to the seventh embodiment. [Figure 7] FIG. 7 is a cross-sectional view of a wiring board according to the eighth embodiment. [Figure 8] FIG. 8 shows the infrared absorption spectrum of the composite material of Example 1 and the infrared absorption spectrum of ZIF-8. [Figure 9] FIG. 9 shows the O1s XPS spectrum of the composite material of Example 1. [Figure 10] FIG. 10 shows the O1s XPS spectrum of ZIF-8. DETAILED DESCRIPTION OF THE INVENTION

[0009] (Findings that formed the basis of this disclosure) In recent years, in the electronics field, the level of performance required of electronic devices has been increasing in preparation for the expansion of fifth-generation mobile communication systems (5G). For example, 5G uses higher frequency bands to enable faster communication speeds than previous generations. This requires electronic devices to have wiring boards that can handle high frequencies. Furthermore, with the aim of improving the packaging density of electronic components as devices become more compact and the amount of information processed increases, there is an increasing demand for multilayer and thin-layer wiring boards.

[0010] Transmission loss in the transmission path of a wiring board depends on frequency, increasing as the signal frequency increases. Transmission loss depends on the dielectric constant and dielectric loss tangent. Therefore, to reduce transmission loss of high-frequency signals, the substrate material that makes up the insulating layer of a wiring board must have a low dielectric constant and dielectric loss tangent. For thin-layer wiring boards, materials with a particularly low dielectric constant are desirable for impedance matching within the circuit.

[0011] Furthermore, high-capacity communications such as 5G use high-frequency bands, which shortens the transmission distance of radio waves. This necessitates an increase in the output power of electronic devices. Furthermore, with the realization of high integration and miniaturization, the density of circuit packaging also increases. Meeting these requirements increases the amount of heat generated per unit area of the wiring board. Therefore, wiring boards are required to have high heat dissipation properties. To improve the heat dissipation properties of wiring boards, the substrate material that makes up the insulating layer of the wiring board is enriched with a filler with excellent thermal conductivity, thereby increasing the thermal conductivity of the wiring board.

[0012] In recent years, metal-organic frameworks (MOFs) have attracted attention as fillers for insulating layers. MOFs, also known as porous coordination polymers (PCPs) or nanoporous metal complexes, are insulating materials. MOFs are crystalline porous materials composed of metal ions or metal clusters and bridging ligands. MOFs have a particularly low dielectric constant. MOFs have the low dielectric constant required for antenna substrates for communication base stations, for example, and can achieve a dielectric constant of 2.0 or less in the high-frequency band from GHz to THz. Furthermore, MOFs can also reduce the dielectric loss tangent by appropriately selecting their crystalline structure. For this reason, MOFs have attracted attention as fillers for insulating layers in wiring boards for various communication applications. For example, Patent Document 1 describes a resin composition for forming an insulating film containing an MOF and a curable resin. MOFs have a negative thermal expansion coefficient, similar to inorganic fillers such as silica particles, which are commonly used as fillers for insulating layers. Furthermore, MOFs have a low dielectric constant due to their large porosity compared to other porous materials, and it is possible to lower the dielectric loss tangent of MOFs by appropriately selecting their crystal structure.

[0013] During the process of mounting electronic components on wiring boards, wiring boards are exposed to alkaline solutions and etching solutions. When the insulating layer material is altered by exposure to these chemicals, the dielectric constant and dielectric loss tangent of the insulating layer change. In wiring boards, changes in the dielectric constant and dielectric loss tangent during the mounting process can cause problems such as increased transmission loss and signal noise due to impedance mismatch. Furthermore, the alteration of the insulating layer material can reduce the mechanical strength of the insulating layer and volatilize by-products, resulting in dimensional changes in the wiring board. In particular, for wiring boards that require thin layers, deviations from the design value and dimensional changes due to changes in the dielectric constant are undesirable. Therefore, the filler in the insulating layer of a wiring board must be resistant to chemical solutions, i.e., chemically stable. Specifically, chemical stability refers to base resistance and acid resistance.

[0014] However, because MOFs have a three-dimensional porous structure constructed by the self-assembly of metal ions or metal clusters and bridging ligands, their structure is easily altered by bases or acids. When the MOF structure is altered and the voids disappear, their chemical stability decreases. This decrease in chemical stability is particularly noticeable in MOFs with a high porosity structure.

[0015] Methods for chemically modifying the surface of MOFs have been proposed to improve the chemical stability of MOFs. For example, Non-Patent Document 1 describes polymerizing dopamine molecules on the surface of an MOF to form a dense polydopamine layer on the surface of the MOF, and then bonding fluorinated alkylthiol molecules to the polydopamine layer via a Michael addition reaction. Non-Patent Document 1 describes that this improves the acid resistance and base resistance of the MOF. Non-Patent Document 2 also describes that various bilayer polymers are formed on the surface of an MOF by coating the surface of an MOF with a polyacrylate polymer having a polymerization initiation point and then polymerizing the polyacrylate polymer in the presence of the polyacrylate polymer. Non-Patent Document 2 also describes that this improves the acid resistance and base resistance of the MOF.

[0016] However, because polydopamine and polyacrylate polymers have many polar functional groups, the chemical modification methods described in Non-Patent Documents 1 and 2 may result in an increase in the dielectric constant and dielectric loss tangent. Furthermore, the chemical modification methods described in Non-Patent Documents 1 and 2 tend to allow the monomer or oligomer components to penetrate into the voids of the MOF during the polymerization reaction. As the polymerization reaction progresses inside the voids of the MOF, the voids become blocked, increasing the dielectric constant and dielectric loss tangent. The penetration of the monomer or oligomer components into the voids is particularly pronounced in MOFs with a high porosity structure.

[0017] Methods for chemically modifying the surface of MOFs at the molecular level have also been proposed. For example, Non-Patent Document 3 describes a method in which a MOF is reacted with a molecule having a phosphate moiety at the end of the alkyl chain, and the metal moiety on the MOF surface is bonded to the phosphate moiety of the alkyl chain, thereby coating the outer surface of the MOF with alkyl chains. Non-Patent Document 3 describes that this method provides the MOF with high water repellency while maintaining its porosity. It also describes that it provides high resistance to acidic and basic aqueous solutions. However, the present inventors' investigations have revealed that the chemical modification method described in Non-Patent Document 3 does not provide sufficient chemical stability.

[0018] Patent Document 2 discloses an organosilicon compound having a specific structure. Patent Document 2 describes that when the organosilicon compound is added to a rubber composition, the hysteresis loss of the cured product is significantly reduced. However, Patent Document 2 does not describe or suggest that modifying the surface of a filler with the organosilicon compound improves the chemical stability of the filler.

[0019] The present inventors have conducted extensive research into improving the chemical stability of materials containing metal-organic frameworks (MOFs), and as a result have come up with the composite material of the present disclosure.

[0020] (Summary of one aspect of the present disclosure) A composite material according to a first aspect of the present disclosure includes a metal organic framework and a silicon-containing polymer, wherein the metal organic framework includes a zeolite-like imidazolate structure, and the silicon-containing polymer includes a main chain having at least one unit selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit. This configuration can improve the chemical stability of the material including the metal organic framework.

[0021] In the second aspect of the present disclosure, for example, in the composite material according to the first aspect, the silicon-containing polymer may be attached to the surface of the metal organic framework. This configuration can further improve the chemical stability of the composite material comprising the metal organic framework.

[0022] In a third aspect of the present disclosure, for example, in the composite material according to the first or second aspect, the zeolite-like imidazolate structure is Zn 2+ and a bridging ligand containing imidazolate. According to the above-mentioned configuration, the chemical stability of the material containing the metal organic framework can be improved.

[0023] In a fourth aspect of the present disclosure, for example, in the composite material according to any one of the first to third aspects, the silicon-containing polymer may include a first side chain having a silicon atom and an oxygen atom, and may be bonded to the metal organic framework via the silicon atom and the oxygen atom. This configuration can further improve the chemical stability of the material containing the metal organic framework. Furthermore, it can also be composited with other compounds without impairing chemical stability.

[0024] In a fifth aspect of the present disclosure, for example, in the composite material according to any one of the first to fourth aspects, the silicon-containing polymer is -SiR 3-n (OX) n wherein n is an integer of 1 to 3, and X represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a bonding portion with the metal organic framework, or a bonding portion with a silicon atom other than the silicon atom of the functional group. At least one X is a bonding portion with the metal organic framework. R represents a hydrocarbon group having 1 to 10 carbon atoms. According to the above configuration, the chemical stability of the material containing the metal organic framework is further improved.

[0025] In a sixth aspect of the present disclosure, for example, in the composite material according to any one of the first to fifth aspects, the silicon-containing polymer may include a second side chain having at least one bond selected from the group consisting of a carbon-carbon double bond and a carbon-carbon triple bond. This configuration improves the heat dissipation of the filler when the composite material is used as a filler.

[0026] In a seventh aspect of the present disclosure, for example, in the composite material according to the sixth aspect, the second side chain may consist of only a chain structure. With this configuration, when the composite material is used as a filler, the heat dissipation property of the filler is improved.

[0027] In an eighth aspect of the present disclosure, for example, in the composite material according to any one of the first to seventh aspects, the silicon-containing polymer may contain a main chain having a butadiene unit. This configuration further improves the chemical stability of the material containing the metal organic framework.

[0028] In a ninth aspect of the present disclosure, for example, in the composite material according to the eighth aspect, the silicon-containing polymer may include a copolymer having a styrene unit and a butadiene unit. This configuration further improves the chemical stability of the material including the metal organic framework.

[0029] In a tenth aspect of the present disclosure, for example, in the composite material according to the fifth aspect, the silicon-containing polymer may be represented by the following formula (1): [ka] In the formula (1), a and d represent numbers equal to or greater than 0, b and c represent numbers greater than 0, and R 1 From R 5 are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or -CH3. However, the order of each repeating unit is arbitrary. According to the above configuration, the chemical stability of the material including the metal organic framework is further improved.

[0030] In the eleventh aspect of the present disclosure, for example, in the composite material according to the tenth aspect, the formula (1) may satisfy 0.15≦c / (b+c+d). This configuration further improves the chemical stability of the material containing the metal organic framework.

[0031] In a twelfth aspect of the present disclosure, for example, in the composite material according to any one of the first to eleventh aspects, the metal organic framework may contain ZIF-8. With the above configuration, excellent dielectric properties are realized.

[0032] A filler according to a thirteenth aspect of the present disclosure includes the composite material according to any one of the first to twelfth aspects. According to the above configuration, a filler with improved chemical stability can be provided.

[0033] A resin composition according to a fourteenth aspect of the present disclosure includes the filler according to the thirteenth aspect. According to the fourteenth aspect, it is possible to provide a filler that exhibits a low dielectric loss tangent and excellent heat resistance.

[0034] A prepreg according to a fifteenth aspect of the present disclosure comprises the resin composition of the fourteenth aspect or a semi-cured product of the resin composition.

[0035] A resin-coated film according to a sixteenth aspect of the present disclosure is A resin layer containing the resin composition of the fourteenth aspect or a semi-cured product of the resin composition; A support film; It is equipped with:

[0036] A resin-coated metal foil according to a seventeenth aspect of the present disclosure is A resin layer containing the resin composition of the fourteenth aspect or a semi-cured product of the resin composition; A metal foil; It is equipped with:

[0037] A metal-clad laminate according to an eighteenth aspect of the present disclosure is An insulating layer comprising a cured product of the resin composition of the fourteenth aspect or a cured product of the prepreg of the fifteenth aspect; A metal foil; It is equipped with:

[0038] A wiring board according to a nineteenth aspect of the present disclosure includes: An insulating layer comprising a cured product of the resin composition of the fourteenth aspect or a cured product of the prepreg of the fifteenth aspect; Wiring and It is prepared.

[0039] According to the fifteenth to nineteenth aspects, various application products suitable for high frequencies can be provided.

[0040] A method for producing a composite material according to a twentieth aspect of the present disclosure includes attaching a silicon-containing polymer to a metal-organic framework, the metal-organic framework including a zeolite-like imidazolate structure, and the silicon-containing polymer including a main chain having at least one unit selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit. This configuration allows the production of a material including a metal-organic framework with improved chemical stability.

[0041] In a 21st aspect of the present disclosure, for example, in the method for producing a composite material according to the 20th aspect, the number average molecular weight of the silicon-containing polymer may be equal to or greater than 1200. This configuration improves the chemical stability of the material containing the metal organic framework.

[0042] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0043] (Embodiment 1) Hereinafter, the first embodiment will be described with reference to FIGS.

[0044] [Composite materials] FIG. 1 is a diagram showing a schematic configuration of a composite material 10 according to a first embodiment. The composite material 10 includes a metal-organic framework 1 (hereinafter referred to as "MOF1") and a silicon-containing polymer 2. In this embodiment, the MOF1 includes a zeolitic imidazolate framework (ZIF). The silicon-containing polymer 2 includes a main chain having at least one unit selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit.

[0045] The silicon-containing polymer 2 may be attached to the surface of MOF 1. The silicon-containing polymer 2 may cover at least a portion of the surface of MOF 1. The silicon-containing polymer 2 may cover the entire surface of MOF 1, or may cover only a portion of the surface of MOF 1.

[0046] The silicon-containing polymer 2 is a low-polarity polymer. Compared to silicon-containing low-molecular-weight compounds such as alkylsilanes, the silicon-containing polymer 2 can prevent water molecules, acids, and bases from reaching the MOF1. The acid is, for example, a proton or an oxonium ion. The base is, for example, a hydroxide ion. Therefore, when the silicon-containing polymer 2 is attached to the surface of the MOF1, the composite material 10 has particularly excellent base and acid resistance. In other words, the composite material 10 has high chemical stability. In this disclosure, the term "silicon-containing low-molecular-weight compound" refers to an organosilicon compound with a molecular weight of less than 1,200.

[0047] Silicon-containing polymer 2 does not easily penetrate into the pores of MOF 1. Furthermore, the main skeleton of the main chain of silicon-containing polymer 2 is a hydrocarbon group, and unlike the polydopamine and polyacrylate polymers used in Non-Patent Documents 1 and 2, it does not have many polar functional groups. Therefore, composite material 10 also suppresses increases in the dielectric constant and dielectric loss tangent. Thus, composite material 10 achieves improved chemical stability while suppressing increases in the dielectric constant and dielectric loss tangent.

[0048] [Metal-organic framework (MOF)] MOF1 includes a zeolite-like imidazolate structure (hereinafter referred to as "ZIF"). MOF1 may be ZIF. ZIF is a general term for MOFs having a three-dimensional crystal structure similar to zeolite. ZIF has a tetrahedral four-coordinate central metal ion (tetrahedral: Td) and a bridging ligand containing imidazolate, and is constructed by a metal-imidazolate-metal coordination bond. The central metal ion may be, for example, Zn 2+ , Co 2+ ZIF is useful because it has high thermal stability and high porosity. Examples of ZIF include ZIF-4, ZIF-7, ZIF-8, ZIF-12, ZIF-67, ZIF-90, ZIF-412, etc. ZIF is a Zn 2+ and a bridging ligand comprising an imidazolate.

[0049] The ZIF may be, for example, ZIF-8. ZIF-8 is a Zn II It is represented by the formula (2-MeIm)2, where 2-MeIm represents 2-methylimidazolate. ZIF-8 is a Zn 2+ ZIF-8 has a sodalite-type crystal structure with 2-methylimidazolate ligands bridged to the nucleus, and has high thermal and chemical stability. ZIF-8 has a helium-equivalent porosity of 48% calculated using the RASPA package (https: / / iraspa.org / ) (see Non-Patent Document 4), and is expected to have a low dielectric constant and low dielectric loss tangent.

[0050] ZIF particles can be used as MOF1 (i.e., ZIF). The shape of the ZIF particles is not particularly limited. The shape of the ZIF particles may be, for example, scale-like, spherical, oval-spherical, rod-like, or amorphous. The average particle size of the ZIF particles is not particularly limited. The average particle size of the ZIF particles may be, for example, 0.01 μm or more and 100 μm or less, or 0.05 μm or more and 50 μm or less. In the present disclosure, the average particle size of the ZIF particles refers to the median diameter. The median diameter refers to the particle size (d50) when the cumulative volume in the volume-based particle size distribution is equal to 50%. The volume-based particle size distribution is measured, for example, by a laser diffraction measurement device.

[0051] [Silicon-containing polymers] Silicon-containing polymer 2 contains silicon atoms and a main chain having at least one unit selected from the group consisting of styrene units, butadiene units, ethylene units, cycloolefin units, and fluorine-containing olefin units. Silicon-containing polymer 2 can inhibit the access of water molecules, acids, and bases compared to silicon-containing low molecular weight compounds such as alkylsilanes. Examples of acids include protons and oxonium ions. Examples of bases include hydroxide ions. Furthermore, due to its structural characteristics, silicon-containing polymer 2 can inhibit the adsorption of moisture from the atmosphere. In addition, silicon-containing polymer 2 is less likely to evaporate when heated compared to silicon-containing low molecular weight compounds such as alkylsilanes. Therefore, silicon-containing polymer 2 is also useful from the perspective of heat resistance.

[0052] In addition to the main chain, the silicon-containing polymer 2 may include a side chain branching from the main chain. The silicon-containing polymer 2 may include multiple side chains. The main chain may include a first main chain composed of carbon atoms bonded to each other. The silicon-containing polymer 2 may include a side chain containing a silicon atom in addition to the first main chain.

[0053] Silicon-containing polymer 2 may include a first side chain having a silicon atom and an oxygen atom. Silicon-containing polymer 2 may be bonded to MOF1 via the silicon atom and the oxygen atom. More specifically, silicon-containing polymer 2 may include an oxygen atom bonded to the silicon atom and MOF1.

[0054] The manner in which silicon-containing polymer 2 binds to MOF1 via silicon and oxygen atoms is assumed to be as follows. Typically, within MOF1, metal ions or metal clusters have a certain number of potential coordination sites, each of which is bound to a bridging ligand. Meanwhile, on the surface of MOF1, at least one of the potential coordination sites of the metal ions or metal clusters remains to which no bridging ligand is bound. It is known that some of the remaining potential coordination sites have a hydroxyl group (-OH) bond (see, for example, Non-Patent Document 5). Therefore, it is expected that an M-OH bond exists on the surface of MOF1. M represents a metal atom. Here, it is known that the M-OH bond forms a strong MO-Si bond, for example, through a silane coupling reaction. Based on the above, it is expected that in composite material 10, silicon-containing polymer 2 binds to MOF1 via the formation of at least one MO-Si bond between silicon-containing polymer 2 and MOF1.

[0055] For example, when MOF1 is ZIF-8, it is expected that there is a Zn-OH bond on the surface of ZIF-8. Therefore, in this case, it is expected that at least one or more Zn-O-Si bonds are formed between the silicon-containing polymer 2 and ZIF-8, thereby binding the silicon-containing polymer 2 to ZIF-8.

[0056] In composite material 10, when silicon-containing polymer 2 is immobilized on the surface of MOF1 by bonding, it can be composited with other compounds without impairing chemical stability. For example, to obtain a resin composition containing composite material 10 and other compounds, a process of dissolving in a predetermined solvent for kneading or a mechanical dispersion process is required. When silicon-containing polymer 2 is immobilized on MOF1 by bonding, even after such a process, the resulting resin composition does not have silicon-containing polymer 2 on the surface of MOF1. A similar situation is avoided when a resin composition containing MOF1, silicon-containing polymer 2, and other compounds is formed in a single process. Thus, when silicon-containing polymer 2 is immobilized on the surface of MOF1 by bonding, the expected chemical stability is exhibited even in the resin composition state.

[0057] Furthermore, in composite material 10, when silicon-containing polymer 2 is fixed to the surface of MOF 1 by bonding, the surface of MOF 1 is constantly covered with a low-polarity polymer, which is expected to improve dispersibility in a specific solvent. Dispersibility is particularly improved in nonpolar solvents. An example of a nonpolar solvent is toluene. This improves the dispersibility of composite material 10 in a resin composition, which can be expected to have effects such as improving the mechanical properties of the resin composition and suppressing variations in the dielectric properties of the resin composition.

[0058] Silicon-containing polymer 2 is -SiR 3-n (OX) nwhere n is an integer of 1 to 3, and X represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a bond to MOF1, or a bond to a silicon atom other than the silicon atom of the functional group. The bond X can also be represented by a single bond (-). The hydrocarbon group having 1 to 10 carbon atoms is, for example, an alkyl group having 1 to 10 carbon atoms, particularly 1 to 3 carbon atoms. At least one X is a bond to MOF1. R represents a hydrocarbon group having 1 to 10 carbon atoms. The silicon-containing polymer 2 having such a structure is immobilized on the surface of MOF1 via an MO-Si bond. Therefore, the surface of MOF1 is more densely covered with the silicon-containing polymer 2, thereby improving the chemical stability of the composite material 10.

[0059] -SiR 3-n (OX) n In the functional group represented by the formula: R may be an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms.

[0060] The alkyl group having 1 to 10 carbon atoms may have a linear, cyclic, or branched structure. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an s-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group, an α-naphthyl group, and a β-naphthyl group.

[0061] Silicon-containing polymer 2 is -SiR 3-n (OX) nand X includes a bond to another silicon atom, the silicon-containing polymer 2 includes a siloxane unit represented by Si-O-Si. The silicon-containing polymer 2 may include a second main chain composed of siloxane units. The silicon-containing polymer 2 having such a structure may have a network structure in which the siloxane units (Si-O-Si) are spread out in a mesh-like pattern.

[0062] The silicon-containing polymer 2 may include a second side chain having at least one bond selected from the group consisting of a carbon-carbon double bond and a carbon-carbon triple bond. With this structure, the carbon-carbon double bond or carbon-carbon triple bond reacts with a reactive residue of the resin in the insulating layer to form a bond, thereby improving the adhesion between the composite material 10 and the resin. This reduces the thermal resistance at the interface between the composite material 10 and the resin, improving the thermal conductivity of the insulating layer. This in turn improves the heat dissipation of the wiring board. Examples of carbon-carbon double bonds include vinyl groups, methallyl groups, and acryloyl groups. The silicon-containing polymer 2 may contain one or more groups selected from these. From the viewpoint of ease of reactivity, the carbon-carbon double bond is preferably a vinyl group. Examples of reactive residues of the resin in the insulating layer include vinyl groups, methallyl groups, and acryloyl groups. Examples of carbon-carbon triple bonds include ethynyl groups and propargyl groups. The silicon-containing polymer 2 may contain one or more of these. Examples of reactive residues in the resin of the insulating layer include ethynyl and propargyl groups. At least one bond selected from the group consisting of a carbon-carbon double bond and a carbon-carbon triple bond may be located at the end of the second side chain. The second side chain may consist solely of a chain structure.

[0063] From the viewpoint of avoiding deterioration due to oxidation, it is desirable that the content of carbon-carbon double bonds and carbon-carbon triple bonds present inside the silicon-containing polymer 2 be small.

[0064] The silicon-containing polymer 2 may further include a side chain other than the first side chain and the second side chain. The side chain other than the first side chain and the second side chain may have, for example, a cyclic structure. The cyclic structure of the side chain may be, for example, an aryl group.

[0065] The silicon-containing polymer 2 may contain a main chain having a butadiene unit. According to the above configuration, the chemical stability of the composite material 10 is further improved.

[0066] The silicon-containing polymer may include a copolymer having a styrene unit and a butadiene unit. This configuration further improves the chemical stability of the composite material 10.

[0067] The silicon-containing polymer 2 may be represented by the following formula (1): According to this configuration, the chemical stability of the composite material 10 is further improved.

[0068] [ka]

[0069] In the above formula (1), a and d represent numbers equal to or greater than 0, b and c represent numbers greater than 0, and R 1 From R 5 are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or -CH3, provided that the order of each repeating unit is arbitrary. 3-n (OX) n The functional group represented by is as explained above. In the part d of the above formula (1), the bond represented by the wavy line means either trans or cis, or a mixture of both.

[0070] In the above formula (1), the silicon-containing polymer 2 may satisfy 0≦a≦500, 1≦b≦500, 1≦c≦500, and 0≦d≦500, or may satisfy 5≦a≦300, 5≦b≦300, 1≦c≦100, and 5≦d≦300.

[0071] In the above formula (1), the silicon-containing polymer 2 may satisfy 5≦a≦100, 5≦b≦100, 1≦c≦80, and 5≦d≦100, or may satisfy 5≦a≦20, 5≦b≦50, 1≦c≦60, and 5≦d≦40.

[0072] In the above formula (1), c represents the repeating number of butadiene units having silicon and oxygen in their side chains. (b+c+d) represents the sum of the butadiene units having repeating number b, the butadiene units having repeating number c, and the butadiene units having repeating number d. In the above formula (1), the silicon-containing polymer 2 may satisfy 0.15≦c / (b+c+d). In other words, in the above formula (1), the value calculated by 100×{c / (b+c+d)} may be 15% or more. This configuration further improves the chemical stability of the composite material 10. In the above formula (1), the value calculated by 100×{c / (b+c+d)} may be 17% or more. The upper limit of the value calculated by 100×{c / (b+c+d)} is, for example, 80%. However, the value calculated by 100×{c / (b+c+d)} is not particularly limited as long as it is within a range in which the desired chemical stability and dielectric properties can be exhibited.

[0073] [Method of manufacturing composite materials] Next, a method for producing the above-mentioned composite material 10 will be described.

[0074] 2 is a flowchart showing an example of a method for producing the composite material 10 according to the first embodiment. The method for producing the composite material 10 includes attaching a silicon-containing polymer 2 to the surface of an MOF 1 (step S1). The MOF 1 includes a ZIF. The silicon-containing polymer 2 includes a main chain having at least one unit selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit.

[0075] In step S1, silicon-containing polymer 2 may be bound to the surface of MOF1 via silicon atoms and oxygen atoms.

[0076] Here, silicon-containing polymer 2 represented by the above formula (1) is represented by the following formula (2) before bonding to MOF 1.

[0077] [ka]

[0078] In the above formula (2), R 6 and R 7 are each independently a hydrocarbon group having 1 to 10 carbon atoms. m is an integer of 1 to 3. a and d are numbers of 0 or more, and b and c are numbers greater than 0.

[0079] In the above formula (2), R 6 and R 7 may each independently represent an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms.

[0080] The alkyl group having 1 to 10 carbon atoms and the aryl group having 6 to 10 carbon atoms are represented by -SiR 3-n (OX) n However, in the above formula (2), as the alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 5 carbon atoms is more preferable, and an alkyl group having 1 to 3 carbon atoms is even more preferable. 6 and R 7 are each independently preferably a straight-chain alkyl group, more preferably a methyl group or an ethyl group.

[0081] In the high-frequency band, ranging from GHz to THz, the dielectric loss tangent is highly dependent on the orientation polarization of the organic molecules contained in the wiring board material. Therefore, the hydroxyl groups present on the surface of MOF1 can increase the dielectric loss tangent. However, the silicon-containing polymer represented by the above formula (2) acts on the hydroxyl groups present on the surface of MOF1, thereby bonding to the MOF surface 1. After bonding, the silicon-containing polymer 2 is represented by the above formula (1). In composite material 10, the bonding of silicon-containing polymer 2 reduces the number of hydroxyl groups present on the surface of MOF1, which is expected to suppress the increase in the dielectric loss tangent.

[0082] The silicon-containing polymer represented by formula (2) can be obtained via the reaction shown in the following scheme. Specifically, a styrene-butadiene copolymer represented by formula (3) and an organosilicon compound represented by formula (4) are hydrosilylated in the presence of a platinum compound-containing catalyst, preferably in the presence of a platinum compound-containing catalyst and a co-catalyst. This allows the silicon-containing polymer represented by formula (2) to be obtained.

[0083] [ka]

[0084] The styrene-butadiene copolymer represented by the formula (3) can be synthesized by a known method such as emulsion polymerization or solution polymerization using butadiene and styrene as raw material monomers. The styrene-butadiene copolymer represented by the formula (3) can also be obtained as a commercially available product. Examples of commercially available products include Ricon 100, Ricon 181, and Ricon 184 (all manufactured by Cray Valley Chemical Industry Co., Ltd.), L-SBR-820 and L-SBR-841 (all manufactured by Kuraray Co., Ltd.), and 1,2-SBS (all manufactured by Nippon Soda Co., Ltd.).

[0085] Examples of the organosilicon compound represented by the above formula (4) include trimethoxysilane, methyldimethoxysilane, dimethylmethoxysilane, triethoxysilane, methyldiethoxysilane, and dimethylethoxysilane.

[0086] Note that the value of c is maintained before and after the silicon-containing polymer is bonded to the surface of MOF1. That is, the value of c in the above formula (2) is equal to the value of c in the above formula (1). Therefore, the silylation rate calculated by 100 × {c / (b+c+d)} in the above formula (2) can be regarded as the silylation rate calculated by 100 × {c / (b+c+d)} in the above formula (1).

[0087] The number average molecular weight of the silicon-containing polymer before bonding to the surface of MOF1 may be 1200 or more, or may be 5000 or more. This configuration improves the density of coverage by the silicon-containing polymer 2, thereby improving the chemical stability of the composite material 10. There is no particular upper limit to the number average molecular weight of the silicon-containing polymer before bonding to the surface of MOF1. The upper limit of the number average molecular weight of the silicon-containing polymer before bonding to the surface of MOF1 is, for example, 10000 or less. In the present disclosure, the number average molecular weight is the polystyrene-equivalent number average molecular weight calculated using gel permeation chromatography (GPC).

[0088] In step S1, silicon-containing polymer 2 may be bonded to the surface of MOF1. For example, if the silicon-containing polymer before bonding to the surface of MOF1 is represented by the above formula (2), silicon-containing polymer 2 can be bonded to the surface of MOF1 by a silane coupling reaction. The silane coupling reaction proceeds as follows: First, the silicon-containing polymer represented by the above formula (2) is hydrolyzed to generate silanol groups (Si-OH). Next, the silanol groups bond to hydroxyl groups partially present on the surface of MOF1 by dehydration condensation. At this time, a metal-oxygen-silicon bond (MO-Si bond) is formed between the silicon-containing polymer and the surface of MOF1 by dehydration condensation. As a result, silicon-containing polymer 2 is immobilized on the surface of MOF1 by bonding. Furthermore, dehydration condensation between silicon-containing polymers 2 can be promoted by heat treatment or the addition of an acid or base. As a result, silicon-containing polymers 2 are continuously bonded to each other via siloxane bonds (Si-O-Si). This also allows for control of the thickness of the silicon-containing polymer 2 layer, which can be determined by selecting appropriate conditions depending on the properties of MOF1, the required dielectric properties and chemical stability, and the properties of the resin in the insulating layer.

[0089] (Embodiment 2) The filler according to this embodiment contains the composite material 10 according to the first embodiment.

[0090] The filler according to the present embodiment may be a filler for forming an insulating layer. In the present disclosure, the filler for forming an insulating layer refers to a filler that is mixed with a resin component and used as an insulating material for a wiring board or a sealing material for an IC chip. When used as a filler for forming an insulating layer, the filler according to the present embodiment can improve chemical stability while suppressing increases in the relative dielectric constant and dielectric loss tangent.

[0091] The filler according to this embodiment can be produced, for example, by kneading the composite material 10 according to embodiment 1 with an epoxy resin or a silicone-based resin, or a non-silicone acrylic resin or a ceramic resin.

[0092] (Embodiment 3) 3 is a diagram showing a schematic configuration of a resin composition 20 according to embodiment 3. The resin composition 20 includes, for example, a filler 22 and a curable resin 24.

[0093] The filler 22 includes the composite material 10 described in the first embodiment. According to this embodiment, it is possible to provide a filler 22 that exhibits a low dielectric tangent and excellent heat resistance. As the filler 22, the composite material 10 alone may be used, or other filler materials such as silica particles may be used in combination with the composite material 10.

[0094] Examples of the curable resin 24 include epoxy resin, cyanate ester compound, maleimide compound, phenol resin, acrylic resin, polyamide resin, polyamideimide resin, thermosetting polyimide resin, polyphenylene ether resin, etc. One or a combination of two or more selected from these may be used.

[0095] Resin composition 20 may contain other components, such as curing agents, flame retardants, ultraviolet absorbers, antioxidants, reaction initiators, silane coupling agents, fluorescent brighteners, photosensitizers, dyes, pigments, thickeners, lubricants, antifoaming agents, dispersants, leveling agents, gloss agents, antistatic agents, polymerization inhibitors, and organic solvents. If necessary, one or a combination of two or more selected from these components may be used.

[0096] (Fourth embodiment) The prepreg according to the fourth embodiment comprises the resin composition 20 of the third embodiment (FIG. 3) or a semi-cured product thereof, and a fibrous base material. The fibrous base material is present in the matrix of the resin composition 20 or the semi-cured product. The prepreg is a composite material of the resin composition 20 and the fibrous base material. According to this embodiment, a prepreg suitable for high-frequency wiring boards can be provided.

[0097] In this embodiment, the semi-cured product refers to a material in a partially cured state where the resin composition 20 can be further cured. In other words, the semi-cured product is a material in a semi-cured state of the resin composition 20. For example, when the resin composition 20 is heated, its viscosity gradually decreases. As the heating continues, curing begins, and the viscosity gradually increases. In such a case, the semi-cured state refers to the state of the resin composition 20 from the point when the viscosity starts to increase until the resin composition 20 is completely cured.

[0098] The fibrous substrate may be any known material used in various types of laminates for electrical insulating materials, such as glass cloth, aramid cloth, polyester cloth, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper.

[0099] The resin composition 20 is impregnated into the fibrous base material by a process such as immersion or coating. The fibrous base material impregnated with the resin composition 20 is heated under predetermined heating conditions to obtain the prepreg according to the present embodiment in an uncured or semi-cured state.

[0100] (Embodiment 5) FIG. 4 is a cross-sectional view of a resin-coated film 30 in embodiment 5. The resin-coated film 30 comprises a resin layer 32 containing the resin composition 20 or a semi-cured product thereof, and a support film 34. According to this embodiment, a resin-coated film 30 suitable for an insulating layer can be provided. The resin layer 32 is supported by the support film 34. In the example of FIG. 4, the support film 34 is disposed on the surface of the resin layer 32. However, another layer such as an adhesive layer may be provided between the resin layer 32 and the support film 34.

[0101] The resin layer 32 contains the resin composition 20 of the third embodiment (FIG. 3) or a semi-cured product thereof, and may or may not contain a fibrous base material. The fibrous base material may be the same material as the fibrous base material of the prepreg. The resin layer 32 hardens and transforms into an insulating layer. An example of such an insulating layer is the insulating layer of a wiring board.

[0102] Any support film used for a resin-coated film can be used without any limitation as the support film 34. Examples of the support film 34 include resin films such as polyester films and polyethylene terephthalate films.

[0103] (Sixth embodiment) FIG. 5 is a cross-sectional view of a resin-coated metal foil 40 according to a sixth embodiment. The resin-coated metal foil 40 comprises a resin layer 42 containing the resin composition 20 or a semi-cured product thereof, and a metal foil 44. The resin layer 42 is supported by the metal foil 44. This embodiment can provide a resin-coated metal foil 40 suitable for electronic circuit components such as wiring boards. In the example of FIG. 5, the metal foil 44 is disposed on the surface of the resin layer 42. However, another layer, such as an adhesive layer, may be disposed between the resin layer 42 and the metal foil 44.

[0104] The resin layer 42 contains the resin composition of the third embodiment (FIG. 3) or a semi-cured product thereof, and may or may not contain a fibrous base material. The fibrous base material may be the same material as the fibrous base material of the prepreg. The resin layer 42 hardens and transforms into an insulating layer. An example of such an insulating layer is the insulating layer of a wiring board.

[0105] There are no limitations on the metal foil 44. Metal foils with resin and metal foils used in metal-clad laminates can be used. Examples of metal foils include copper foil and aluminum foil.

[0106] (Embodiment 7) FIG. 6 is a cross-sectional view of a metal-clad laminate 50 according to a seventh embodiment. The metal-clad laminate 50 includes an insulating layer 52 and at least one metal foil 54. According to this embodiment, a metal-clad laminate 50 suitable for a wiring board can be provided. The insulating layer 52 includes a cured product of the resin composition 20 of the third embodiment (FIG. 3) or a cured product of the prepreg of the fourth embodiment. The metal foil 54 is disposed on the surface of the insulating layer 52. In this embodiment, a metal foil 54 is disposed on each of the front and back surfaces of the insulating layer 52.

[0107] The metal-clad laminate 50 is typically manufactured using the prepreg of the fourth embodiment. For example, 1 to 20 prepregs are stacked to form a laminate. Metal foil is placed on one or both sides of the prepreg laminate, and the laminate is heated and pressed to obtain the metal-clad laminate 50. Examples of the metal foil 54 include copper foil and aluminum foil.

[0108] The molding conditions for producing the metal-clad laminate 50 may be, for example, the molding conditions for producing laminates and multilayer boards for electrical insulating materials.

[0109] (Embodiment 8) FIG. 7 is a cross-sectional view of wiring board 60 in embodiment 8. Wiring board 60 includes insulating layer 62 and wiring 64. According to this embodiment, it is possible to provide wiring board 60 suitable for high frequencies. Insulating layer 62 includes a cured product of resin composition 20 of embodiment 3 (FIG. 3) or a cured product of the prepreg of embodiment 4. Wiring 64 is supported by insulating layer 62. More specifically, wiring 64 is disposed on insulating layer 62. Wiring 64 can be formed by partially removing the metal foil.

[0110] By patterning the metal foil 54 on the surface of the metal-clad laminate 50 (FIG. 6) by a method such as etching, a wiring board 60 is obtained in which wiring 64 forming a circuit is provided on the surface of the insulating layer 62. In other words, the wiring board 60 is obtained by partially removing the metal foil 54 on the surface of the metal-clad laminate 50 so that a circuit is formed.

[0111] A new laminate may be formed by laminating the prepreg of embodiment 5 on at least one surface of wiring board 60 and then applying heat and pressure. A multilayer wiring board can be obtained by patterning the metal foil on the surface of the obtained laminate to form wiring. [Example]

[0112] The present disclosure will be specifically described below with reference to examples. The examples are intended to illustrate the present disclosure and are not intended to limit the scope of the present disclosure.

[0113] Example 1 [Metal-organic framework (MOF)] ZIF-8 particles (manufactured by Aldrich, product name: Basolite Z1200) were used as the MOF.

[0114] [Synthesis of silicon-containing polymers] As the silicon polymer, a silicon-containing polymer represented by the above formula (2) was synthesized. Specifically, a styrene-butadiene copolymer represented by the above formula (3) (manufactured by Nippon Soda Co., Ltd., product number: 1,2-SBS) and an organosilicon compound represented by the above formula (4) (manufactured by Tokyo Chemical Industry Co., Ltd., product number: T0135, m = 3, R 6 =H) was hydrosilylated in the presence of a platinum catalyst. This resulted in the silicon-containing polymer of Example 1 represented by the above formula (2). The composition of the resulting silicon-containing polymer was as follows: 1The ratio of the integrals of the peaks corresponding to each functional group in the profile obtained by H nuclear magnetic resonance (NMR) measurement (600 MHz) was determined. The NMR device used was a JEOL JNM ECZ600R. As a result, the silicon-containing polymer of Example 1 was found to have the following structure: a = 10, b = 61, c = 13, d = 0, m = 3, R 6 = methyl group (-CH3). The silylation rate of the silicon-containing polymer of Example 1 was 17.6%. The silylation rate was determined by the formula -SiR 2 3-m (OR 1 ) m The number average molecular weight of the silicon-containing polymer was determined to be 5,900 by GPC measurement (Tosoh Corporation, HLC-8320GPC).

[0115] [Synthesis of composite materials] 2.5 g of silicon-containing polymer was dissolved in 5 mL of toluene to obtain a first solution. Next, 2 g of ZIF-8 particles were added to 20 mL of toluene, and the particles were dispersed using an ultrasonic cleaner to obtain a second solution. While stirring the second solution with a magnetic stirrer, the previously prepared first solution was added and stirred at room temperature for 12 hours. Powder was then obtained by filtration. Toluene was added to the obtained powder, and the mixture was subjected to ultrasonic dispersion, followed by centrifugation to remove the supernatant. The above washing procedure was repeated three times, and the mixture was then dried in the air. This yielded the composite material particles of Example 1.

[0116] [Calculation of silicon-containing polymer content] The silicon-containing polymer content in the composite material of Example 1 was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). A Thermo Fisher Scientific iCAP7400 Duo was used as the ICP-AES instrument. The molar ratio of Si to Zn obtained by the measurement was 0.029. The silicon-containing polymer content in the composite material of Example 1 was calculated from the obtained molar ratio, the proportion and molecular weight of Zn calculated from the composition formula of ZIF-8, and the proportion and molecular weight of Si calculated from the composition formula of the silicon-containing polymer. The calculated value was 6.5 wt%.

[0117] [Confirmation of silicon-containing polymer bonding] The bonding of the silicon-containing polymer to the surface of ZIF-8 in the composite material of Example 1 was confirmed by the infrared absorption spectrum and O1s XPS spectrum of the composite material. The infrared absorption spectrum was obtained by the diffuse reflectance method of Fourier transform infrared spectroscopy (FT-IR).

[0118] Figure 8 shows the infrared absorption spectrum of the composite material of Example 1 and the infrared absorption spectrum of ZIF-8. In Figure 8, the horizontal axis represents wave number (cm -1 ) and the vertical axis represents transmittance (%). Note that since FIG. 8 is a diagram for comparing the trends of the two infrared absorption spectra, the scale of the vertical axis is omitted. As shown in FIG. 8, a peak due to the deformation vibration of the vinyl group was observed in the composite material of Example 1, confirming the presence of a silicon-containing polymer on the surface of ZIF-8.

[0119] Figure 9 shows the O1s XPS spectrum of the composite material of Example 1. Figure 10 shows the O1s XPS spectrum of ZIF-8. In Figures 9 and 10, the horizontal axis represents binding energy (eV), and the vertical axis represents intensity in arbitrary units. As shown in Figure 9, peak separation in the O1s XPS spectrum of the composite material of Example 1 confirmed Si-O-Zn bonds and Si-O-Si bonds. These results confirmed that in the composite material of Example 1, the silicon-containing polymer was immobilized on the surface of ZIF-8 via Zn-O-Si bonds.

[0120] [Preparation of membranes containing composite materials] The film of Example 1 containing 40 vol % of the composite material particles of Example 1 was produced by the following method. The density of the composite material particles was 0.921 g / cm 3 The density of all other components is 1g / cm 3 First, 0.7950 g of reactive low-molecular-weight (molecular weight 2400) polyphenylene ether (resin main component), 0.0900 g of allyl cyanurate derivative (Shikoku Kasei Corporation, product name: L-DAIC) (crosslinking aid), 0.0150 g of dicumyl peroxide (polymerization initiator), and 0.5526 g of the composite material particles of Example 1 were added to 5 mL of toluene in this order to obtain a mixture. The mixture was dispersed using an ultrasonic cleaner for 3 minutes and then stirred with a magnetic stirrer for 30 minutes to obtain a suspension. The suspension was heated at 90°C for 1 hour, followed by repeated vacuum pumping at 110°C for 3 minutes. This resulted in a paste-like solid from which the solvent had been removed. The paste-like solid was pressed at 150°C and 10 MPa for 5 minutes, and then pressed at 190°C and 10 MPa for 5 minutes to harden. Thereafter, the membrane was evacuated at 200°C for 12 hours to obtain the membrane of Example 1. The thickness of the membrane of Example 1 was 0.273 mm. The membrane thickness was measured at any five points on the membrane and calculated as the average of the measured values.

[0121] Comparative Example 1 The MOF used in Example 1 was ZIF-8 particles (manufactured by Aldrich, product name: Basolite Z1200). In Comparative Example 1, a composite material was synthesized using polydopamine instead of the silicon-containing polymer. Dopamine has recently attracted attention as a natural adhesive that strongly bonds to the surface of inorganic fillers. 4.2 g of tris(hydroxymethylaminomethane) was dissolved in 100 mL of deionized water, followed by the addition of hydrochloric acid to obtain a Tris buffer solution adjusted to pH 7. Next, 3 g of ZIF-8 particles were added to the Tris buffer solution, and while stirring with a magnetic stirrer, 2.25 g of dopamine hydrochloride was added. The mixture was stirred at 80 °C for 20 hours. The mixture was then filtered to obtain a powder. Deionized water was added to the obtained powder, which was then subjected to ultrasonic dispersion, followed by centrifugation to remove the supernatant. The above washing procedure was repeated three times, followed by drying in the air, to obtain the composite material particles of Comparative Example 1. The color of the powder changed from white to gray, which is characteristic of the dopamine layer, confirming that the surface of the ZIF-8 powder was modified with a dopamine layer.

[0122] The polydopamine content in the composite material of Comparative Example 1 was determined by thermogravimetric analysis (TGA) measurement and was found to be 12.0 wt %.

[0123] Comparative Example 2 The MOF used was the ZIF-8 particles (manufactured by Aldrich, product name: Basolite Z1200) used in Example 1. In Comparative Example 2, a composite material was synthesized using 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KBM-503) instead of the silicon-containing polymer. 3-methacryloxypropyltrimethoxysilane is a common silane coupling agent made of a silicon-containing low-molecular-weight compound. Surface modification was performed using the same method as in Example 1, except that the silicon-containing polymer was changed to 3-methacryloxypropyltrimethoxysilane.

[0124] The content of 3-methacryloxypropyltrimethoxysilane in the composite material of Comparative Example 2 was determined by the same method as in Example 1. The molar ratio of Si to Zn obtained by measurement was 0.035. The content of 3-methacryloxypropyltrimethoxysilane in the composite material of Comparative Example 2 was calculated from the obtained molar ratio, the proportion and molecular weight of Zn calculated from the composition formula of ZIF-8, and the proportion and molecular weight of Si calculated from the composition formula of 3-methacryloxypropyltrimethoxysilane. The calculated value was 3.7 wt%.

[0125] The film of Comparative Example 2 was produced in the same manner as in Example 1, except that the composite particles of Comparative Example 2 were used as the composite particles. The thickness of the film of Comparative Example 2 was 0.268 mm.

[0126] Comparative Example 3 As the particles of Comparative Example 3, the ZIF-8 particles (manufactured by Aldrich, product name: Basolite Z1200) used in Example 1 were used as they were.

[0127] The membrane of Comparative Example 3 was produced by the same method as in Example 1, except that the ZIF-8 particles of Comparative Example 3 were used as the composite particles. The thickness of the membrane of Comparative Example 3 was 0.260 mm.

[0128] The dielectric properties and chemical stability of each of the particles obtained in the above-mentioned Examples and Comparative Examples were evaluated before and after surface modification based on the methods described below.

[0129] [Evaluation of particle pore volume before and after surface modification] The pore volume of ZIF-8 particles before and after surface modification at a relative pressure of 0.99 was calculated by nitrogen adsorption measurement at 77 K. A BELSORP MINI X manufactured by Microtrac-Bell was used as the nitrogen adsorption measurement device. For the measurement, the particles were pretreated under vacuum (10 Pa or less) at 200°C for 1 hour. The results are shown in Table 1.

[0130] [Evaluation of dielectric properties of particles before and after surface modification] The relative permittivity and dielectric loss tangent of ZIF-8 particles before and after surface modification were measured using a cavity resonance method at a frequency of 1 GHz. The cavity resonator used was the MS46122B manufactured by AET. For the measurement, the particles were pretreated under vacuum (10 Pa or less) at 200°C for 1 hour. Measurements were then carried out in the atmosphere. The packing fraction of the sample tube was calculated from the true density of ZIF-8, and the relative permittivity and dielectric loss tangent of the particles were calculated. The relative permittivity and dielectric loss tangent of the particles were calculated by converting the measured values into the packing fraction of the sample tube. The packing fraction of the sample tube was determined from the mass of the particles, the bulk volume occupied by the particles in the sample tube, and the true density of each particle. The true density of ZIF-8 was determined using the density (0.921 g / cm) calculated from the crystal structure. 3 ) was used. The true density of the particles after surface modification was determined using the following formulas (X1) and (Y1). The porosity of ZIF-8 was set to 50%. The results are shown in Table 1. If the relative permittivity after surface modification was 2.00 or less and the dielectric dissipation factor was 0.003 or less, it was determined that the dielectric properties had not deteriorated due to the surface modification. True density of particles after surface modification = (density calculated from the crystal structure of ZIF-8) ÷ ((porosity of ZIF-8 × 0.01) × (porosity maintenance rate) × 0.01) Formula (X1) Pore retention rate = (pore volume of particle after surface modification) ÷ (pore volume of particle before surface modification) Equation (Y1)

[0131] [Evaluation of chemical stability of film before and after etching process] The dielectric constant of the film containing the composite particles was measured before and after etching using a cavity resonance method at a frequency of 40 GHz. An AET MS46122B cavity resonator was used. The results are shown in Table 1. If the absolute value of the change in dielectric constant before and after etching was 0.02 or less, the film was deemed to have sufficient chemical stability to prevent design problems when used as an insulating layer in a wiring board. Note that a value of 0.02 or less is also within the measurement device's error range (±0.02). The etching process was performed under the following conditions. The etchant used was a cupric chloride solution (HCl concentration 2.5 mol / L, containing CuCl2, HO2, and HO), which is commonly used in copper plate patterning processes. A 4 cm x 4 cm piece of film was immersed in the etchant at room temperature for 80 hours. The film was then washed multiple times with water and vacuumed at 40°C for 30 minutes. This yielded the etched film.

[0132] [Table 1]

[0133] ≪Consideration≫ As shown in Table 1, in Example 1, no deterioration in the relative permittivity and dielectric loss tangent was observed after surface modification, and excellent dielectric properties were exhibited.

[0134] As shown in Table 1, in Example 1, almost no change in the relative dielectric constant was observed before and after the etching treatment, and excellent chemical stability was exhibited. This is thought to be because in Example 1, the etching treatment caused almost no change in the structure of ZIF-8.

[0135] On the other hand, in Comparative Example 1, the surface modification increased the relative permittivity and dielectric loss tangent, and the dielectric properties deteriorated. This is thought to be because a polymerization reaction proceeded inside the voids of ZIF-8 during the surface modification, causing the voids to be blocked, and because the hydroxyl groups (-OH) present in large quantities in the dopamine skeleton were exposed to the surface. In Comparative Example 2, the deterioration of the dielectric properties due to the surface modification was somewhat alleviated compared to Comparative Example 1, but the relative permittivity changed due to the etching treatment, as in Comparative Example 3 without a surface modification layer. This is thought to be because in Comparative Example 2, the structure of ZIF-8 collapsed due to the etching treatment, particles were eluted in the etching solution, and voids were generated.

[0136] Thus, the composite material of Example 1 exhibited improved chemical stability while suppressing increases in dielectric constant and dielectric loss tangent. Therefore, by using such a composite material as a filler, it is expected that the resin composition will have a low dielectric constant and that the three-dimensional porous structure of the MOF will be prevented from being altered by etching. As a result, it is possible to provide a product that can be mounted as an insulating layer on a wiring board.

[0137] In this example, ZIF-8 is used as the MOF, but it is expected that even if ZIF such as ZIF-4, ZIF-7, ZIF-12, ZIF-67, ZIF-90, or ZIF-412 is used instead of ZIF-8, the increase in the dielectric constant and dielectric loss tangent will be suppressed and chemical stability will be improved. This is because the composite material of the present disclosure contains an MOF and a silicon-containing polymer, which suppresses the increase in the dielectric constant and dielectric loss tangent while improving chemical stability.

[0138] In order to express the present disclosure, the present disclosure has been appropriately and sufficiently described above through the embodiments, but it should be recognized that those skilled in the art can easily change and / or improve the above-described embodiments. Therefore, unless the changes or improvements made by those skilled in the art are at a level that deviates from the scope of the claims described in the claims, the changes or improvements are interpreted as being encompassed within the scope of the claims. [Industrial Applicability]

[0139] The composite material of the present disclosure can realize a filler with excellent dielectric properties and chemical stability, and is therefore suitable for applications such as wiring boards for electronic devices used in high-capacity communications. [Explanation of symbols]

[0140] 1 Metal-organic framework 2. Silicon-containing polymers 10 Composite materials 20 Resin composition 22 Filler 24 Curing resin 30 Resin-coated film 32 Resin layer 34 Support film 40 Resin-coated metal foil 42 Resin layer 44 Metal foil 50 Metal clad laminate 52 Insulating layer 54 Metal foil 60 Wiring board 62 Insulating layer 64 Wiring

Claims

1. a metal-organic framework; a silicon-containing polymer; the metal organic framework comprises a zeolite-like imidazolate framework; The silicon-containing polymer comprises a main chain having at least one unit selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit. Composite material.

2. the silicon-containing polymer is attached to the surface of the metal organic framework; The composite material of claim 1.

3. The zeolite-like imidazolate structure is 2+ and a bridging ligand comprising an imidazolate, The composite material of claim 1.

4. the silicon-containing polymer includes a first side chain having a silicon atom and an oxygen atom, and is bonded to the metal organic framework via the silicon atom and the oxygen atom; The composite material of claim 1.

5. The silicon-containing polymer is —SiR 3-n (OX) n having a functional group represented by The composite material of claim 1. Here, n is an integer of 1 to 3, and X represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a bonding portion with the metal organic framework, or a bonding portion with a silicon atom other than the silicon atom of the functional group. At least one X is a bonding portion with the metal organic framework. R represents a hydrocarbon group having 1 to 10 carbon atoms.

6. the silicon-containing polymer comprises a second side chain having at least one bond selected from the group consisting of a carbon-carbon double bond and a carbon-carbon triple bond; The composite material of claim 1.

7. the second side chain consists solely of a chain structure, The composite material of claim 6.

8. The silicon-containing polymer comprises a backbone having butadiene units. The composite material of claim 1.

9. The silicon-containing polymer comprises a copolymer having styrene units and butadiene units.

9. The composite material of claim 8.

10. The silicon-containing polymer is represented by the following formula (1): The composite material of claim 5. 【Chemical 1】 In the formula (1), a and d represent numbers equal to or greater than 0, b and c represent numbers greater than 0, and R 1 From R 5 are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or —CH 3 However, the order of the repeating units is arbitrary.

11. In the formula (1), 0.15≦c / (b+c+d) is satisfied. The composite material of claim 10.

12. The metal organic framework comprises ZIF-8. The composite material of claim 1.

13. Comprising the composite material of claim 1 . Filler.

14. Comprising the filler of claim 13. Resin composition.

15. The resin composition according to claim 14 or a semi-cured product of the resin composition, Prepreg.

16. A resin layer comprising the resin composition according to claim 14 or a semi-cured product of the resin composition; A support film; A resin-coated film comprising:

17. A resin layer comprising the resin composition according to claim 14 or a semi-cured product of the resin composition; Metal foil; A resin-coated metal foil comprising:

18. An insulating layer comprising a cured product of the resin composition according to claim 14 or a cured product of the prepreg according to claim 15; Metal foil and A metal-clad laminate comprising:

19. An insulating layer comprising a cured product of the resin composition according to claim 14 or a cured product of the prepreg according to claim 15; Wiring and Equipped with a wiring board.

20. attaching a silicon-containing polymer to the metal organic framework; the metal organic framework comprises a zeolite-like imidazolate framework; The silicon-containing polymer comprises a main chain having at least one unit selected from the group consisting of a styrene unit, a butadiene unit, an ethylene unit, a cycloolefin unit, and a fluorine-containing olefin unit. Composite material manufacturing methods.

21. The number average molecular weight of the silicon-containing polymer is 1200 or more. A method for producing the composite material of claim 20.

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