Composites and sensors containing organometallic structures

Abstract

The present invention provides a composite of organometallic structures in which organometallic structure particles do not easily detach and which does not significantly degrade the performance of sensors when used in such devices. [Solution] The problem is solved by a composite comprising an organometallic structure and a polymer compound having an oxazoline group, wherein the organometallic structure is a particulate organometallic structure having a carboxyl group, and the polymer compound having an oxazoline group has a weight-average molecular weight of 3000 or more, exists only outside the pores of the organometallic structure, and contains an amide ester bond formed by the bonding of the oxazoline group of the polymer compound and the carboxyl group of the organometallic structure.

Description

[Technical Field]

[0001] This invention relates to composites and sensors comprising organometallic structures. [Background technology]

[0002] Metal-organic frameworks (MOFs) are porous materials synthesized using coordination bonds between metal ions and organic substances, and have recently attracted attention as porous materials with functions such as gas storage and separation.

[0003] As a composite material containing an organometallic structure and a polymer, Patent Document 1 discloses a thermally conductive resin composition comprising a porous coordination polymer having a predetermined thermal conductivity and a thermoplastic resin as a binder, and states that the porous coordination polymer may further contain an organic polymer within its pores. Patent Document 2 discloses the use of a material in which polymer chains of a temperature-sensitive polymer material are formed within the porous cavity of a water-stable metal-organic structure for water capture and release. Patent Document 3 discloses a metal-organic skeleton material having pores containing a polymer suitable for adsorbing at least one substance. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2008-63413 [Patent Document 2] Special Publication No. 2022-552101 [Patent Document 3] Special Publication No. 2009-519116 [Overview of the project] [Problems that the invention aims to solve]

[0005] Organometallic structures have a large specific surface area and extremely high gas adsorption capacity, making them promising for highly sensitive gas detection as gas sensors. However, when using organometallic structures as gas sensors, there is a problem in that, for example, if the organometallic structure is coated onto a substrate, the organometallic structure particles easily detach. On the other hand, if the organometallic structure is immobilized with a binder, the organometallic structure particles become dispersed in the binder, which leads to a decrease in sensor performance.

[0006] One aspect of the present invention aims to provide a composite of organometallic structures in which organometallic structure particles do not easily detach and which does not easily degrade the performance of the sensor when used in a sensor. [Means for solving the problem]

[0007] To solve the aforementioned problems, the present invention includes the following embodiments.

[0008] [1] A composite comprising an organometallic structure and a polymer compound having an oxazoline group, wherein the organometallic structure is a particulate organometallic structure having a carboxyl group, and the polymer compound having an oxazoline group has a weight-average molecular weight of 3000 or more, is present only outside the pores of the organometallic structure, and contains an amide ester bond formed by the bonding of the oxazoline group of the polymer compound and the carboxyl group of the organometallic structure.

[0009] [2] The composite according to [1], wherein the pore size of the organometallic structure is 2 nm or less.

[0010] [3] The complex according to [1] or [2], wherein the amount of oxazoline groups per gram of the organometallic structure is 0.006 mmol to 0.028 mmol.

[0011] [4] A sensor composite, as described in any one of [1] to [3].

[0012] [5] A laminate comprising a substrate and a composite according to any one of [1] to [4].

[0013] [6] The laminate according to [5], wherein the substrate is an electrode or a glass substrate.

[0014] [7] A sensor comprising the composite according to any one of [1] to [4], or the laminate according to [5] or [6].

[0015] [8] The sensor according to [7], which is a humidity sensor. [Advantages of the Invention]

[0016] According to one aspect of the present invention, it is possible to provide a composite of an organometallic structure in which the organometallic structure particles are not easily detached and the performance of the sensor is not easily deteriorated when used in the sensor. [Brief Description of the Drawings]

[0017] [Figure 1] It is a diagram schematically showing a state in which organometallic structure particles are immobilized by bonding an oxazoline group of a polymer compound having an oxazoline group and a carboxy group of an organometallic structure. [Figure 2] It is a diagram showing the result of evaluating the immobilization of organometallic structure particles for the composite obtained in Example 1. [Figure 3] It is a diagram showing the result of evaluating the immobilization of organometallic structure particles for the composite obtained in Example 2. [Modes for Carrying Out the Invention] ​​​​​​​[1. Complex] A composite according to one embodiment of the present invention is a composite comprising an organometallic structure and a polymer compound having an oxazoline group, wherein the organometallic structure is a particulate organometallic structure having a carboxyl group, and the polymer compound having an oxazoline group has a weight-average molecular weight of 3000 or more, is present only outside the pores of the organometallic structure, and contains an amide ester bond formed by the bonding of the oxazoline group of the polymer compound to the carboxyl group of the organometallic structure.

[0020] The aforementioned composite has the advantages that the organometallic structure particles do not easily detach, and that when used in a sensor, the performance of the sensor is less likely to deteriorate.

[0021] (organometallic structure) In this disclosure, a metal-organic framework (MOF) is a structurally ordered compound composed of metal ions and organic ligands, and is a porous material having multiple pores.

[0022] A composite according to one embodiment of the present invention includes an organometallic structure having a carboxyl group. The organometallic structure having a carboxyl group is not particularly limited, and for example, organometallic structures having carboxyl groups described in Patent Documents 1 to 3 can be used.

[0023] The organic ligand constituting the organometallic structure is not particularly limited as long as it is an organic compound having at least two carboxyl groups, and may be an aliphatic compound or an aromatic compound.

[0024] If the organic ligand is an aliphatic compound, the aliphatic compound may be saturated or unsaturated. Furthermore, the aliphatic compound may be linear or branched, and may contain a ring. The number of carbon atoms in the aliphatic compound is not particularly limited, but is, for example, 2 to 40. Examples of the aliphatic compound include fumaric acid and 1,3-butadiene-1,4-dicarboxylic acid.

[0025] If the organic ligand is an aromatic compound, the aromatic compound may have one or more aromatic rings, for example, 1 to 7 or 1 to 4. The aromatic rings may be monocyclic or fused rings. The aromatic rings may also be heterocyclic. The aromatic compound is not particularly limited, but examples include terephthalic acid, isophthalic acid, 2,5-franzicarboxylic acid, 1,3,5-benzenetricarboxylic acid (trimesic acid), benzene-1,2-dicarboxylic acid, biphenyl-4,4'-dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,3,5-tris(4'-carboxy[1,1'-biphenyl]-4-yl)benzene, 1,3,5-tris(4-carboxyphenyl)benzene (benzenetribenzoate), and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene (benzenetetrabenzoate). Examples include [1,1':4',1'']terphenyl-3,3'',5,5''-tetracarboxylic acid, biphenyl-3,3',5,5'-tetracarboxylic acid, biphenyl-3,4',5-tricarboxylic acid, 3,3',5,5'-tetracarboxydiphenylmethane, 9,10-anthracenedicarboxylic acid, tetrakis(4-carboxyphenyl)porphyrin, 4,4',4'-s-triazine-2-2,4,6-tolyl-tribenzoic acid, 2,3,6,7,10,11-hexahydroxytriphenylene, and 2,3,6,7,10,11-heximinotriphenylene.

[0026] The aforementioned organic ligand may be used individually or in combination of two or more types.

[0027] Furthermore, the metal ions constituting the organometallic structure are not particularly limited, and ions of elements selected from alkali metals, alkaline earth metals, transition metals, and metals (including metalloids) belonging to groups 12 to 16 of the periodic table can be chosen. These metal ions may be used individually or in combination of two or more. A more preferred example of the metal ions is Zr 4+ , Al 3+ Cu 2+, Co 2+ , Ni 2+ , Zn 2+ , Pt 2+ , Ag + , Cu + , Cr 2+ , Cr 3+ , Fe 2+ , Fe 3+ , Ti 2+ , Hf 4+ , La 3+ , Mg 2+ and the like. Among these, from the viewpoint of being able to form a metal ion dimer unit, divalent or higher metal ions are preferred.

[0028] The combination of the organic ligand constituting the organometallic structure having the carboxy group and the metal ion may be any combination. Also, the composite according to an embodiment of the present invention may contain one kind of organometallic structure or may contain two or more kinds of organometallic structures.

[0029] More specific examples of the organometallic structure include, for example, UiO-66, MIL160, MIL-53, MIL-96, MIL-100, MIL-101, MIL-125, HKUST-1, aluminium fumarate MOF, MOF-5, MOF-74, MOF-199, MOF-508, MOF-801, MOF-867, MTAF-3 and the like.

[0030] The organometallic structure may be particulate. The average particle size of the organometallic structure is, for example, 0.05 μm to 100.0 μm, more preferably 0.1 μm to 10.0 μm, more preferably 0.1 μm to 6.0 μm, and even more preferably 1.0 μm to 5.0 μm. An average particle size of 0.05 μm or more is preferable because sufficient water molecules can be adsorbed inside the particles. Furthermore, an average particle size of 100.0 μm or less is preferable because MOF particles can be bound to the substrate. The average particle size of the organometallic structure is calculated by arbitrarily selecting 10 particles from an SEM image taken using a scanning electron microscope, measuring their particle sizes, and taking the average value of those measurements.

[0031] The organometallic structure has pores ranging from micropores with a pore diameter of 2 nm or less to mesopores with a pore diameter of 2 nm to 50 nm. In one embodiment of the present invention, the pore diameter of the organometallic structure is preferably 6.0 nm or less, more preferably 4.0 nm or less, and even more preferably 2.0 nm or less. The lower limit of the pore diameter is not particularly limited, but for example, it is 0.4 nm or more. A pore diameter of 6.0 nm or less is preferable because it allows for sufficient surface area for water molecule adsorption. Furthermore, if the pore diameter is 6.0 nm or less, polymers cannot enter the pores, but gas molecules or water molecules can, making it suitable for use in gas sensors and humidity sensors. Additionally, a pore diameter of 0.4 nm or more is preferable because water molecules can be adsorbed into the MOF pores.

[0032] (Polymer compounds containing oxazoline groups) A composite according to one embodiment of the present invention contains a polymer compound having an oxazoline group. This allows the oxazoline group of the polymer compound to bond with the carboxyl group of the organometallic structure, thereby immobilizing the organometallic structure particles in a way that prevents them from easily detaching. Furthermore, it has been found that using a polymer compound having an oxazoline group results in less degradation of sensor performance when used in a sensor.

[0033] The polymer compound having an oxazoline group is not particularly limited as long as it is a polymer compound having an oxazoline group and a weight-average molecular weight of 3000 or more. If the weight-average molecular weight of the polymer compound having an oxazoline group is 3000 or more, it can suitably bridge and immobilize organometallic structures. The weight-average molecular weight of the polymer compound having an oxazoline group is more preferably 10000 or more, and even more preferably 20000 or more. There is no particular upper limit to the weight-average molecular weight of the polymer compound having an oxazoline group, but it is more preferably 100000 or less. Here, the weight-average molecular weight is the value measured by gel permeation chromatography (GPC).

[0034] The main chain skeleton of the polymer compound having the oxazoline group is not particularly limited. Examples of the main chain skeleton of the polymer compound include skeletons selected from the group consisting of vinyl polymers, (meth)acrylic polymers, styrene polymers, styrene / (meth)acrylic polymers, styrene / acetonitrile polymers, siloxane polymers, cycloolefin polymers, methylpentene polymers, amide polymers, aromatic ester polymers, polyester polymers, polyimide polymers, polyamide polymers, polyamideimide polymers, and cellulose polymers. Among these, skeletons selected from the group consisting of vinyl polymers, (meth)acrylic polymers, styrene polymers, and styrene / (meth)acrylic polymers are more preferred.

[0035] The polymer compound having the oxazoline group may be, for example, a polymer (or copolymer) containing constituent units derived from an oxazoline group-containing monomer, and can be produced, for example, by copolymerizing the oxazoline group-containing monomer with a monomer copolymerizable therewith.

[0036] The oxazoline group-containing monomers are not limited to these, but include, for example, 2-vinyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 5-methyl-2-vinyl-2-oxazoline, and 4,4-dimethyl-2-vinyl-2-oxazoline. The oxazoline group-containing monomers can be used individually or in combination of two or more.

[0037] Examples of monomers copolymerizable with the oxazoline group-containing monomer include alkyl (meth)acrylates, aromatic vinyls, maleimide group-containing monomers, vinyl cyanide monomers, and styrene monomers. Examples of alkyl (meth)acrylates include (meth)acrylates having linear or branched alkyl groups with 1 to 20, more preferably 2 to 10 carbon atoms. Examples of aromatic vinyls include styrene, o-alkylstyrene, m-alkylstyrene, p-alkylstyrene, o-ethylstyrene, m-ethylstyrene, p-ethylstyrene, dimethylstyrene, tert-methylstyrene, α-chlorostyrene, β-chlorostyrene, and divinylbenzene. The monomers copolymerizable with the oxazoline group-containing monomer can be used individually or in combination of two or more.

[0038] More specific examples of polymer compounds having the oxazoline group include, for example, Epocross WS-700, WS-300, WS-500, K-2010E, K-2020E, K-2035E, and RPS-1005 (all manufactured by Nippon Shokubai).

[0039] The amount of oxazoline groups in the polymer compound having the oxazoline groups is not particularly limited, but for example, it is 0.0001 mmol / g (solids) to 100.000 mmol / g (solids), more preferably 0.001 mmol / g (solids) to 10.000 mmol / g (solids), even more preferably 0.006 mmol / g (solids) to 5.000 mmol / g (solids), even more preferably 0.010 mmol / g (solids) to 1.000 mmol / g (solids), and even more preferably 0.010 mmol / g (solids) to 0.020 mmol / g (solids). If the amount of oxazoline groups is 0.0001 mmol / g (solids) or more, the detachment of organometallic structure particles can be suitably reduced. Furthermore, if the solid content is 100,000 mmol / g or less, it is preferable because the performance of the sensor is less likely to deteriorate when the composite is used in the sensor.

[0040] The glass transition temperature of the polymer compound having the oxazoline group is not particularly limited, but is, for example, 70°C to 200°C, more preferably 80°C to 150°C, and even more preferably 100°C to 130°C. A glass transition temperature of 100°C or higher is preferable, especially when used in humidity sensors, as it corresponds to the temperature at which water exists in the gas phase. A glass transition temperature of 200°C or lower is preferable because it ensures the solubility of the polymer.

[0041] The polymer compound having the oxazoline group exists only outside the pores of the organometallic structure. Figure 1 schematically shows how the organometallic structure particles are immobilized by the bonding of the oxazoline group of the polymer compound having the oxazoline group to the carboxyl group of the organometallic structure. Figure 1 shows an example in which UiO-66 is used as the organometallic structure. As shown in Figure 1, the particles of the organometallic structure have a carboxyl group on the surface of the particle, and this carboxyl group bonds with the oxazoline group of the polymer compound to form an amide ester bond. This bond connects multiple particles of the organometallic structure by a chain of the polymer compound having the oxazoline group, forming a crosslinked structure. As a result, the particles of the organometallic structure are immobilized and do not easily detach. Thus, the oxazoline group of the polymer compound bonds with the carboxyl group on the surface of the particle and does not enter the pores, so the polymer compound having the oxazoline group exists only outside the pores of the organometallic structure. Furthermore, the composite includes an amide ester bond formed by the bonding of the oxazoline group of the polymer compound with the carboxyl group of the organometallic structure.

[0042] In other words, the composite according to one embodiment of the present invention does not contain a polymer compound having an oxazoline group in the pores of the organometallic structure. However, the composite according to one embodiment of the present invention may contain other components other than the polymer compound having an oxazoline group in the pores of the organometallic structure. The other components that may be contained in the pores may be polymer compounds or low molecular weight compounds, but are preferably low molecular weight compounds, and more preferably low molecular weight compounds with a molecular weight of less than 200. It is preferable that the pores do not contain components with a molecular weight of 200 or more, or that they do not contain the other components, because the amount of adsorption of gaseous component molecules is not significantly reduced. Examples of low molecular weight compounds with a molecular weight of less than 200 include gases and solvents, but may also contain components other than gases and solvents.

[0043] (complex) The weight ratio of the organometallic structure to the content of the polymer compound having oxazoline groups (content of organometallic structure / content of polymer compound having oxazoline groups) is preferably 150 to 700. If the weight ratio is 700 or less, the organometallic structure particles can be immobilized in a way that prevents them from easily detaching. If the weight ratio is 150 or more, the performance of the sensor is less likely to deteriorate when the composite is used in a sensor. The weight ratio is more preferably 200 to 500, and even more preferably 240 to 400.

[0044] Furthermore, in the composite according to one embodiment of the present invention, the amount of oxazoline groups contained per gram of the organometallic structure is preferably 0.006 mmol to 0.028 mmol. If the amount of oxazoline groups is 0.006 mmol or more, the organometallic structure particles can be immobilized in a way that prevents them from easily detaching. If the amount of oxazoline groups is 0.028 mmol or less, the performance of the sensor is less likely to deteriorate when the composite is used in a sensor. The amount of oxazoline groups is more preferably 0.009 mmol to 0.023 mmol, and even more preferably 0.011 mmol to 0.019 mmol.

[0045] Furthermore, the content of the organometallic structure relative to the content of the polymer compound having an oxazoline group (content of organometallic structure / content of polymer compound having an oxazoline group) is preferably 170 to 630 in molar ratio. If the weight ratio is 170 or more, the organometallic structure particles can be immobilized so that they do not easily detach. If the molar ratio is 640 or less, the performance of the sensor is less likely to deteriorate when the composite is used in a sensor. The molar ratio is more preferably 200 to 500, and even more preferably 240 to 400.

[0046] The shape of the composite according to one embodiment of the present invention is not particularly limited, and may be, for example, a block, a film, a plate, or a sheet.

[0047] (Method of manufacturing the composite) The method for producing the composite is not particularly limited and may include, for example, a step of forming a layer of the organometallic structure on a substrate (step I) and a step of adding a polymer compound having an oxazoline group on the layer of the organometallic structure (step II).

[0048] In step I, for example, a layer of the organometallic structure is formed by dropping or coating the slurry of the organometallic structure onto a substrate. The method of coating the slurry of the organometallic structure is not particularly limited. When dropping or coating the slurry of the organometallic structure, it is more preferable to keep the substrate heated to, for example, 80°C to 140°C. This allows the dispersant to evaporate rapidly from the slurry. The dispersion medium is not particularly limited, but examples include alcohols such as ethanol, isopropyl alcohol, and 2,2,3,3-tetrafluoro-1-propanol, acetone, ethyl acetate, toluene, and combinations of two or more of these. The amount of organometallic structure contained in the slurry of the organometallic structure is, for example, 0.1 mg / mL to 3.0 mg / mL, and more preferably 0.5 mg / mL to 2.0 mg / mL. It is preferable that the amount of organometallic structure be within the above range so that the organometallic structure is properly dispersed in the dispersion medium and a film thickness that functions as a sensor can be ensured by coating.

[0049] In step II, a polymer compound having an oxazoline group is dropped or coated onto the layer of the organometallic structure to obtain a composite comprising the organometallic structure and the polymer compound having an oxazoline group. It is preferable to drop or coat the polymer compound having an oxazoline group in the form of a solution, such as an aqueous solution. It is even more preferable to keep the layer of the organometallic structure heated to, for example, 80°C to 140°C when dropping or coating the solution of the polymer compound having an oxazoline group. This promotes the bonding between the oxazoline group of the polymer compound and the carboxyl group of the organometallic structure, and also allows for the rapid evaporation of the solvent in the solution of the polymer compound having an oxazoline group.

[0050] The method for producing the composite may further include a drying step of drying the composite, which comprises an organometallic structure and a polymer compound having an oxazoline group. In the drying step, the drying temperature is, for example, 100°C to 180°C, and the drying time is 10 minutes to 2 hours.

[0051] The method for producing the composite may further include a step of preparing a slurry of the organometallic structure.

[0052] The method for producing the composite is not limited to a method comprising steps I and II. For example, a mixture comprising the organometallic structure and a polymer compound having an oxazoline group may be prepared, and the mixture may be dropped or coated onto the substrate.

[0053] [2. Laminates] One aspect of the present invention also includes a laminate comprising a composite according to the present embodiment and a substrate.

[0054] (base material) The substrate is not particularly limited, but examples include electrodes, glass substrates, alumina substrates, glass epoxy substrates, polyethylene substrates, etc. When the substrate is an electrode, it can be suitably used as a sensor. Therefore, the composite according to one embodiment of the present invention may be a sensor composite. The electrode is not particularly limited, but examples include comb-shaped electrodes, flat plate electrodes, etc. The structure of the electrode is not particularly limited, and may consist of a single layer or multiple layers. The electrode may be, for example, an electrode in which a conductive layer is formed on a substrate. The conductive layer of the electrode may be connected to a substrate, such as a glass substrate, via an adhesive layer. The adhesive layer may be an adhesive, a tack, or a metal such as titanium or chromium. The material of the conductive layer is not particularly limited as long as it is conductive, and examples include metals such as gold, platinum, and silver, or carbon materials such as carbon.

[0055] The laminate can be manufactured by laminating the composite on the substrate using the method described in "Method for Manufacturing the Composite". The composite laminated on the substrate is preferably in the form of a film. The thickness of the film-like composite is, for example, 0.1 μm to 20.0 μm, and more preferably 1.0 μm to 10.0 μm.

[0056] [3. Sensors] One aspect of the present invention also includes a sensor comprising the laminate. Because the organometallic structure has a large specific surface area and an extremely large gas adsorption capacity, the composite obtained by immobilizing the organometallic structure using a polymer compound having an oxazoline group can be suitably used in sensors such as gas sensors and humidity sensors.

[0057] As a sensor according to one embodiment of the present invention, a laminate in which the composite is formed on the aforementioned electrodes can be suitably used. For example, a gas sensor, a humidity sensor, etc., comprises a container in which the laminate is placed inside, a gas introduction section for introducing the gas to be measured into the container, and a measuring device for measuring the volume between electrodes. The gas to be measured is not particularly limited and can be water vapor, nitrogen, argon, hydrogen, carbon dioxide, nitrogen dioxide, sulfur dioxide, carbon monoxide, nitric oxide, hydrogen sulfide, ammonia, formaldehyde, volatile alcohols such as methanol, halogen gases such as chlorine, hydrogen halide gases such as hydrogen chloride, fluorocarbon gases, etc. [Examples]

[0058] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0059] [Evaluation Method] The evaluation methods used in the examples and comparative examples are described below.

[0060] <Evaluation of immobilization of organometallic structure particles> The composites obtained in the examples and comparative examples were evaluated for the immobilization of organometallic structural particles using a stylus-type surface profile analyzer, Dektak XT (manufactured by Bruker AXS Co., Ltd.). Specifically, two scans were performed with a stylus pressure of 1 mg, a measurement distance of 0.5 mm, and a measurement time of 30 seconds. If no scan marks were observed on the surface of the composite and the two profiles matched, it was determined that the organometallic structural particles were immobilized. If scan marks were observed on the surface of the composite in at least one of the two scans, it was determined that the organometallic structural particles were not immobilized.

[0061] <Evaluation of the impact of adding polymer compounds containing oxazoline groups on sensor performance> For the composites obtained in the examples, the inter-electrode capacity was measured using comb-type electrodes before and after the addition of the polymer compound containing oxazoline groups, under both a dry nitrogen atmosphere and a high-humidity nitrogen atmosphere. The effect of adding the polymer compound containing oxazoline groups on the sensor performance was evaluated by comparing the capacity difference between the dry nitrogen atmosphere and the high-humidity nitrogen atmosphere before and after the addition of the polymer compound containing oxazoline groups. Here, the comb-type electrode before the addition of the polymer compound containing oxazoline groups refers to the comb-type electrode that formed the organometallic structure film before the aqueous solution of the polymer compound containing oxazoline groups was dropped onto it. The comb-type electrode after the addition of the polymer compound containing oxazoline groups refers to the final composite containing the organometallic structure and the polymer compound containing oxazoline groups. Note that in the comb-type electrode before the addition of the polymer compound containing oxazoline groups, some particles of the organometallic structure detached from the film, but measurements were taken in this state.

[0062] High-humidity nitrogen was generated by passing dry nitrogen from a gas cylinder through a gas absorption tube containing deionized water. A commercially available humidity sensor was used to measure the humidity of both the dry nitrogen from the gas cylinder and the generated high-humidity nitrogen.

[0063] The capacitance between electrodes was measured by placing a comb-shaped electrode inside a polyvinyl chloride tube, connecting it to a capacitance meter (Agilent 4288A), and measuring the capacitance at a frequency of 1 MHz.

[0064] First, a comb-shaped electrode containing an oxazoline group was placed inside a polyvinyl chloride tube before the addition of the polymer compound. Dry nitrogen was then flowed through the tube at a flow rate of 1 L / min, and the volume between the electrodes was measured. Next, the gas flowing through the tube was switched from dry nitrogen to high-humidity nitrogen by operating a valve. The high-humidity nitrogen was then flowed at a flow rate of 1 L / min, and the volume between the electrodes was measured 20 minutes after the switch to obtain stable measurements. The difference between the volume under a dry nitrogen atmosphere and the volume under a high-humidity nitrogen atmosphere was defined as the volume difference due to humidity change.

[0065] Next, the volume of the comb-shaped electrode after adding the polymer compound containing an oxazoline group was measured in the same manner under a dry nitrogen atmosphere and under a high-humidity nitrogen atmosphere, and the difference was defined as the volume difference due to humidity change. After switching between dry nitrogen and high-humidity nitrogen, the volume between the electrodes was measured 20 minutes after the switch.

[0066] The smaller or no difference between the volume difference due to humidity change before the addition of the polymer compound containing oxazoline groups and the volume difference due to humidity change after the addition of the polymer compound containing oxazoline groups, the smaller the effect of adding the polymer compound containing oxazoline groups can be considered.

[0067] [Example 1] UiO-66 (AP0010, manufactured by Atomis Co., Ltd.) was dispersed using ethanol as a dispersion medium under ultrasonic waves for 30 minutes to prepare a slurry with a solid content of 1.5 mg / mL. UiO-66 is composed of terephthalic acid and Zr 4+ It is an organometallic structure formed from [the specified components].

[0068] As the substrate, a comb-shaped electrode was used, in which a conductive layer made of gold with a thickness of 100 nm was formed on a glass substrate via a 10 nm thick adhesive layer made of titanium. The line width / space width (L / S) of the comb-shaped electrode was 10 μm / 5 μm, and the length of the counter electrode was 4 mm. The comb-shaped electrode was placed on a hot plate heated to 120°C, and after heating to 120°C, a UiO-66 film was formed on the comb-shaped electrode by dropping 100 μL of UiO-66 slurry onto it.

[0069] 100 μL of a solution prepared by diluting Epocross WS700 (manufactured by Nippon Shokubai, non-volatile content: 25% by weight, oxazoline group content: 4.5 mmol / g (solids), specific gravity: 1.05 g / mL), a water-soluble oxazoline group-containing polymer, 50 times by volume with deionized water, was dropped onto the UiO-66 film on a hot plate heated to 120°C. The mixture was then dried in an oven at 120°C for 30 minutes to obtain a composite containing an organometallic structure and a polymer compound having oxazoline groups. The diluted Epocross WS700 solution spread uniformly on the UiO-66 film upon dropping and did not spread outside the UiO-66 film. At this time, the weight ratio of UiO-66 to Epocross WS700 (before dilution) was 70:1 (the weight ratio of UiO-66 to the solids content of Epocross WS700 was 70:0.25 = 280:1). Furthermore, the amount of oxazoline group per 1 g of UiO-66 was 0.016 mmol.

[0070] When the immobilization of the organometallic structural particles was evaluated in the obtained composite, no scan marks were observed on the surface of the composite. Furthermore, as shown in Figure 2, the two profiles were identical, indicating that the organometallic structural particles were immobilized.

[0071] An evaluation of the effect of adding a polymer compound containing an oxazoline group on the performance of the sensor revealed that the capacity difference due to humidity change before the addition of the polymer compound containing an oxazoline group was 5.2 pF, and the capacity difference due to humidity change after the addition of the polymer compound containing an oxazoline group was 5.1 pF. This indicates that the addition of the polymer compound containing an oxazoline group has no effect on the humidity response. Furthermore, measurements using a commercially available humidity sensor showed that the humidity of dry nitrogen was 3.2%, and the humidity of high-humidity nitrogen was 80.4%.

[0072] [Example 2] The same procedure as in Example 1 was followed, except that MIL160 (AP5040, manufactured by Atomis Corporation) was used instead of UiO-66, to form a MIL160 film on a comb-shaped electrode and obtain a composite containing an organometallic structure and a polymer compound having an oxazoline group. MIL160 is composed of 2,5-franzicarboxylic acid and Al 3+ It is an organometallic structure formed from the above. When the diluted Epocross WS700 was dropped, it spread uniformly on the MIL160 film and did not spread outside the MIL160 film. At this time, the weight ratio of MIL160 to Epocross WS700 (before dilution) was 60:1 (the weight ratio of MIL160 to the solid content of Epocross WS700 was 60:0.25 = 240:1). Also, the amount of oxazoline group per 1 g of MIL160 was 0.019 mmol.

[0073] When the immobilization of the organometallic structural particles in the obtained composite was evaluated, no scan marks were observed on the surface of the composite. Furthermore, as shown in Figure 3, the two profiles were identical, indicating that the organometallic structural particles were immobilized.

[0074] An evaluation of the effect of adding a polymer compound containing an oxazoline group on the performance of the sensor revealed that the capacity difference due to humidity change before the addition of the polymer compound containing an oxazoline group was 4.2 pF, and the capacity difference due to humidity change after the addition of the polymer compound containing an oxazoline group was 4.1 pF. This indicates that the addition of the polymer compound containing an oxazoline group has no effect on the humidity response. Furthermore, measurements using a commercially available humidity sensor showed that the humidity of dry nitrogen was 5.6%, and the humidity of high-humidity nitrogen was 75.2%.

[0075] [Example 3] The same procedure as in Example 1 was followed, except that HKUST-1 (AP0002, manufactured by Atomis Co., Ltd.) was used instead of UiO-66, to form an HKUST-1 film on a comb-shaped electrode and obtain a composite containing an organometallic structure and a polymer compound having an oxazoline group. HKUST-1 is composed of trimesic acid and Cu 2+ It is an organometallic structure formed from the above. When the diluted Epocross WS700 was added dropwise, it spread uniformly on the HKUST-1 film and did not spread outside the HKUST-1 film. At this time, the weight ratio of HKUST-1 to Epocross WS700 (before dilution) was 80:1 (the weight ratio of HKUST-1 to the solid content of Epocross WS700 was 80:0.25 = 320:1). Also, the amount of oxazoline group per 1 g of HKUST-1 was 0.014 mmol.

[0076] When the immobilization of the organometallic structural particles in the obtained composite was evaluated, no scan marks were observed on the surface of the composite. Furthermore, the two profiles were consistent, indicating that the organometallic structural particles were immobilized.

[0077] An evaluation of the effect of adding a polymer compound containing an oxazoline group on the performance of the sensor revealed that the capacity difference due to humidity change before the addition of the polymer compound containing an oxazoline group was 4.9 pF, and the capacity difference due to humidity change after the addition of the polymer compound containing an oxazoline group was 4.7 pF. This indicates that the addition of the polymer compound containing an oxazoline group has no effect on the humidity response. Furthermore, measurements using a commercially available humidity sensor showed that the humidity of dry nitrogen was 3.6%, and the humidity of high-humidity nitrogen was 85.9%.

[0078] [Example 4] The same procedure as in Example 1 was followed, except that aluminum fumarate MOF (AP5015, manufactured by Atomis Corporation) was used instead of UiO-66, to form an aluminum fumarate MOF film on a comb-shaped electrode and obtain a composite containing an organometallic structure and a polymer compound having an oxazoline group. The aluminum fumarate MOF is composed of fumaric acid and Al 3+ It is an organometallic structure formed from the above. When the diluted Epocross WS700 was added dropwise, it spread uniformly on the aluminum fumarate MOF film and did not spread outside the aluminum fumarate MOF film. At this time, the weight ratio of aluminum fumarate MOF to Epocross WS700 (before dilution) was 50:1 (the weight ratio of aluminum fumarate MOF to Epocross WS700 solid content was 50:0.25 = 200:1). Also, the amount of oxazoline groups per 1g of aluminum fumarate MOF was 0.023 mmol.

[0079] When the immobilization of the organometallic structural particles in the obtained composite was evaluated, no scan marks were observed on the surface of the composite. Furthermore, the two profiles were consistent, indicating that the organometallic structural particles were immobilized.

[0080] An evaluation of the effect of adding a polymer compound containing an oxazoline group on the performance of the sensor revealed that the capacity difference due to humidity change before the addition of the polymer compound containing an oxazoline group was 3.9 pF, and the capacity difference due to humidity change after the addition of the polymer compound containing an oxazoline group was 3.8 pF. This indicates that the addition of the polymer compound containing an oxazoline group has no effect on the humidity response. Furthermore, measurements using a commercially available humidity sensor showed that the humidity of dry nitrogen was 3.8%, and the humidity of high-humidity nitrogen was 88.7%.

[0081] [Comparative Example 1] Except for using ZIF-8 (AP0008, manufactured by Atomis Corporation) instead of UiO-66, the same procedure as in Example 1 was followed to form a ZIF-8 film on a comb-shaped electrode, obtaining a composite containing an organometallic structure and a polymer compound having an oxazoline group. ZIF-8 is composed of 2-methylimidazole and Zn 2+ It is an organometallic structure formed from the above. When the diluted Epocross WS700 was added dropwise, it spread uniformly on the ZIF-8 film and did not spread outside the ZIF-8 film. At this time, the weight ratio of ZIF-8 to Epocross WS700 (before dilution) was 30:1 (the weight ratio of ZIF-8 to the solid content of Epocross WS700 was 30:0.25). Also, the amount of oxazoline group per 1 g of ZIF-8 was 0.038 mmol.

[0082] When the immobilization of the organometallic structural particles in the obtained composite was evaluated, scan marks were observed in the first scan, indicating that the organometallic structural particles were not immobilized.

[0083] [Comparative Example 2] The same procedure as in Example 1 was followed, except that Mn-btt (synthetic) was used instead of UiO-66, to form a Mn-btt film on a comb-shaped electrode and obtain a composite containing an organometallic structure and a polymer compound having an oxazoline group. Mn-btt is composed of 1,3,5-benzenetristetrazolate and Mn 2+It is an organometallic structure formed from the above. When the diluted Epocross WS700 was added dropwise, it spread uniformly on the Mn-btt film and did not spread outside the Mn-btt film. At this time, the weight ratio of Mn-btt to Epocross WS700 (before dilution) was 40:1 (the weight ratio of Mn-btt to the solid content of Epocross WS700 was 40:0.25). Also, the amount of oxazoline group per 1 g of Mn-btt was 0.028 mmol.

[0084] When the immobilization of the organometallic structural particles in the obtained composite was evaluated, scan marks were observed in the first scan, indicating that the organometallic structural particles were not immobilized.

[0085] [Example 5] A composite containing an organometallic structure and a polymer compound having an oxazoline group was obtained by performing the same procedure as in Example 1, except that 144 μL of a 50-fold deionized water dilution of Epocross WS700, which was dropped onto the UiO-66 membrane on a hot plate heated to 120°C, was used. The weight ratio of UiO-66 to Epocross WS700 (before dilution) dropped onto the UiO-66 membrane was 50:1 (the weight ratio of UiO-66 to the solid content of Epocross WS700 was 50:0.25 = 200:1). The amount of oxazoline groups per 1 g of UiO-66 was 0.023 mmol.

[0086] When the immobilization of the organometallic structural particles in the obtained composite was evaluated, no scan marks were observed on the surface of the composite. Furthermore, the two profiles were consistent, indicating that the organometallic structural particles were immobilized.

[0087] An evaluation of the effect of adding a polymer compound containing an oxazoline group on the performance of the sensor revealed that the capacity difference due to humidity change before the addition of the polymer compound containing an oxazoline group was 4.8 pF, and the capacity difference due to humidity change after the addition of the polymer compound containing an oxazoline group was 6.2 pF. This indicates that although there was a slight effect on the humidity response due to the addition of the polymer compound containing an oxazoline group, it was still possible to measure the humidity difference. For reference, measurements using a commercially available humidity sensor showed that the humidity of dry nitrogen was 3.6%, and the humidity of high-humidity nitrogen was 80.2%. [Industrial applicability]

[0088] This invention can be used in sensors such as gas sensors and humidity sensors.

Claims

1. A composite comprising an organometallic structure and a polymer compound having an oxazoline group, The aforementioned organometallic structure is a particulate organometallic structure having a carboxyl group, The polymer compound having the oxazoline group has a weight-average molecular weight of 3000 or more and is present only outside the pores of the organometallic structure. A composite comprising an amide ester bond formed by bonding the oxazoline group of the polymer compound to the carboxyl group of the organometallic structure.

2. The composite according to claim 1, wherein the pore diameter of the organometallic structure is 2 nm or less.

3. The composite according to claim 1, wherein the amount of oxazoline groups per gram of the organometallic structure is 0.006 mmol to 0.028 mmol.

4. The composite device according to claim 1, which is a sensor composite device.

5. A laminate comprising a substrate and the composite described in claim 1.

6. The laminate according to claim 5, wherein the substrate is an electrode or a glass substrate.

7. A sensor comprising a composite according to any one of claims 1 to 4, or a laminate according to claim 5 or 6.

8. The sensor according to claim 7, which is a humidity sensor.

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