Metal-organic framework, gas adsorbent, kneaded yarn, textile product, and resin composite

Abstract

Disclosed is a metal-organic framework which has at least one metal atom selected from the group consisting of Zr, Zn, Al, and Mg, and an organic ligand that has at least one group selected from the group consisting of a carboxy group and a carboxylate group, and which includes a partial defect of the organic ligand.

Description

Metal organic frameworks, gas adsorbents, kneaded yarns, textile products and resin composites

[0001] The present disclosure relates to a metal-organic framework, a gas adsorbent, a kneaded yarn, a textile product, and a resin composite.

[0002] "Mad odor" refers to unpleasant odors that can be perceived by humans. Malodors include those generated by business activities, as defined in the Offensive Odor Prevention Act. Malodors also include human body odor and everyday odors (such as the smell of garbage). Eliminating these odors in our daily lives is important for preserving our living environment.

[0003] Gas adsorbents for malodors have been developed using various materials, including activated carbon and zeolite. Among these, metal-organic frameworks (MOFs, also known as "porous metal complexes") have recently attracted attention for use as gas adsorbents. A "metal-organic framework" is a porous three-dimensional structure formed from a central metal and organic ligands. Metal-organic frameworks, also known as MOFs (metal organic frameworks), have been widely studied in recent years. Metal-organic frameworks are characterized by their large specific surface area and design freedom. MOFs have uniform micropores and a large specific surface area. Therefore, high adsorption performance can be expected.

[0004] Patent Document 1 proposes the use of MOFs as deodorizers for everyday odors. Patent Document 2 proposes the use of MOFs as deodorizers for malodors. Patent Documents 3 and 4 propose the use of MOFs as adsorbents for aldehyde gases originating from tobacco and the like.

[0005] JP 2019-88499 A International Publication No. 2007 / 035596 International Publication No. 2015 / 046417 U.S. Patent No. 9,307,790

[0006] The problem to be solved by the present disclosure is to provide a metal organic framework capable of adsorbing various gases that cause malodors, and a gas adsorbent including the metal organic framework. Another problem to be solved by the present disclosure is to provide a kneaded yarn, a textile product, or a resin composite that uses the gas adsorbent.

[0007] Means for solving the above problems include the following aspects. [1] A metal-organic structure comprising: at least one metal atom selected from the group consisting of Zr, Zn, Al, and Mg; and an organic ligand having at least one group selected from the group consisting of a carboxy group and a carboxylate group, wherein the metal-organic structure contains partial defects in the organic ligand. [1-1] The metal-organic structure according to [1], in which a defect rate of the organic ligand is 1 to 99%. [1-2] The metal-organic structure according to [1] or [1-1], in which a defect rate of the organic ligand is 5 to 80%. [1-3] The metal-organic structure according to any of [1] to [1-2], in which a defect rate of the organic ligand is 20 to 50%. [2] The metal-organic structure according to any of [1] to [1-3], in which a nitrogen atom content is less than 5 mass% relative to the total mass of the metal-organic structure. [3] The metal-organic structure according to any one of [1] to [2], wherein the content of nitrogen atoms is 0.5% by mass or less, relative to the total mass of the metal-organic structure. [4] The metal-organic structure according to any one of [1] to [3], wherein the content of nitrogen atoms is 0.1% by mass or less, relative to the total mass of the metal-organic structure. [5] The metal-organic structure according to any one of [1] to [4], wherein the metal atom is Zr. [6] The metal-organic structure according to any one of [1] to [5], wherein the organic ligand is a polycarboxylic acid or an anion thereof. [7] The metal-organic structure according to any one of [1] to [6], wherein the organic ligand is a polycarboxylic acid having a benzene skeleton or an anion thereof. [8] The metal-organic structure according to any one of [1] to [7], wherein the organic ligand is terephthalic acid or an anion thereof. [9] The metal organic structure according to any one of [1] to [8], wherein the metal atom is Zr, the organic ligand is terephthalic acid or an anion thereof, and the molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:0.01 or more and less than 6.

[10] The metal organic structure according to [9], wherein the molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:3.00 or more and 5.70 or less.[10-1] The metal-organic structure according to [9] or

[10] , wherein a molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:3.00 or more and 5.50 or less. [10-2] The metal-organic structure according to any one of [9] to [10-1], wherein a molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:3.00 or more and 5.30 or less. [10-3] The metal-organic structure according to any one of [9] to [10-2], wherein a molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:3.50 or more and 5.00 or less. [10-4] The metal-organic structure according to any one of [9] to [10-3], wherein a molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:4.00 or more and 4.90 or less. [10-5] The metal organic structure according to any one of [9] to [10-4], wherein a molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:4.50 or more and 4.80 or less.

[11] A metal organic structure represented by the following formula (A): [Zr. ６ (OH) ４ O ４ (bdc) ｎ L ｘ(A) (wherein bdc is terephthalic acid or an anion thereof, n is 0.01 or more and less than 6, L is a ligand other than bdc, and x is an arbitrary number of 0 or more).

[12] The metal organic structure according to any one of [1] to [8], represented by the following formula: [12-1] The metal organic structure according to

[11] , wherein n in formula (A) is 3.00 or more and 5.50 or less. [12-2] The metal organic structure according to any one of

[11] to [12-1], wherein n in formula (A) is 3.50 or more and 5.00 or less. [12-3] The metal organic structure according to any one of

[11] to [12-2], wherein n in formula (A) is 3.50 or more and 4.80 or less.

[13] A gas adsorbent comprising the metal organic framework according to any one of [1] to [12-3].

[14] The gas adsorbent according to

[13] , for adsorbing malodorous gases.

[15] The gas adsorbent according to

[13] , for adsorbing at least one gas selected from the group consisting of acidic gases, basic gases, aldehyde gases, and VOC gases. [15-1] The gas adsorbent according to

[13] , for adsorbing acidic gases. [15-2] The gas adsorbent according to

[13] , for adsorbing basic gases. [15-3] The gas adsorbent according to

[13] , for adsorbing aldehyde gases. [15-4] The gas adsorbent according to

[13] , for adsorbing VOC gases.

[16] The gas adsorbent according to

[13] , for adsorbing acidic gases, basic gases, aldehyde gases, and VOC gases.

[17] A kneaded yarn comprising the gas adsorbent according to any one of

[13] to

[16] .

[18] A textile product comprising the gas adsorbent according to any one of

[13] to

[16] .

[19] A resin composite comprising the gas adsorbent according to any one of

[13] to

[16] .

[0008] [A1] A method for adsorbing a gas, comprising contacting the metal organic framework according to any one of [1] to [12-3] with a gas and adsorbing the gas. [A2] The method according to [A1], wherein the gas is a malodorous gas. [A3] The method according to [A1], wherein the gas is at least one gas selected from the group consisting of an acidic gas, a basic gas, an aldehyde gas, and a VOC gas. [A4] The method according to [A1], wherein the gas is an acidic gas. [A5] The method according to [A1], wherein the gas is a basic gas. [A6] The method according to [A1], wherein the gas is an aldehyde gas. [A7] The method according to [A1], wherein the gas is a VOC gas. [A8] The method according to [A1], wherein the gas is an acidic gas, a basic gas, an aldehyde gas, or a VOC gas.

[0009] [B1] Use of the metal organic framework according to any one of [1] to [12-3] as a gas adsorbent. [B2] The use according to [B1], wherein the gas is a malodorous gas. [B3] The use according to [B1], wherein the gas is at least one gas selected from the group consisting of an acidic gas, a basic gas, an aldehyde gas, and a VOC gas. [B4] The use according to [B1], wherein the gas is an acidic gas. [B5] The use according to [B1], wherein the gas is a basic gas. [B6] The use according to [B1], wherein the gas is an aldehyde gas. [B7] The use according to [B1], wherein the gas is a VOC gas. [B8] The use according to [B1], wherein the gas is an acidic gas, a basic gas, an aldehyde gas, or a VOC gas.

[0010] According to the present disclosure, there can be provided a metal-organic framework capable of adsorbing various gases that cause malodors, and a gas adsorbent including the metal-organic framework. According to the present disclosure, there can be provided a kneaded yarn, a textile product, or a resin composite using the gas adsorbent.

[0011] Fig. 1 shows the results of thermogravimetric analysis of the metal organic framework produced in Example 1. Fig. 2 shows a powder X-ray crystallography (PXRD) spectrum of the metal organic framework produced in Example 1. Fig. 3 shows a powder X-ray crystallography (PXRD) spectrum of the metal organic framework produced in Reference Example 1. Fig. 4 shows a powder X-ray crystallography (PXRD) spectrum of the metal organic framework produced in Comparative Example 1.

[0012] The following description of the constituent elements may be based on representative embodiments of the present disclosure, but the present disclosure is not limited to such embodiments. In the present specification, the term "to" is used to mean that the numerical values ​​before and after it are included as upper and lower limits. In numerical ranges described in stages in this specification, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. In numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. In this disclosure, when multiple substances corresponding to each component are present in the composition, the amount of each component in the composition refers to the total amount of the multiple substances present in the composition, unless otherwise specified. In this disclosure, the term "step" includes not only independent steps, but also steps that cannot be clearly distinguished from other steps, as long as the intended purpose of the step is achieved. In this disclosure, "mass %" and "wt %" are synonymous, and "parts by mass" and "parts by weight" are synonymous. In this disclosure, a combination of two or more preferred aspects is a more preferred aspect. The contents of the present disclosure will be described in detail below.

[0013] (Gas Adsorbent) The gas adsorbent according to the present disclosure includes a metal organic framework. The metal organic framework has at least one metal atom selected from the group consisting of Zr, Zn, Al, and Mg, and an organic ligand having at least one group selected from the group consisting of a carboxy group and a carboxylate group, and includes partial defects in the organic ligand. The gas adsorbent according to the present disclosure can be suitably used as an adsorbent for at least one gas selected from the group consisting of acidic gases, basic gases, aldehyde gases, and VOC (volatile organic compound) gases. Furthermore, the gas adsorbent according to the present disclosure can be suitably used as a gas adsorbent for resin kneading, and more suitably used as a gas adsorbent for polyester resin kneading. The gas adsorbent according to one embodiment of the present disclosure can be used for various applications as a deodorizer. The gas adsorbent according to one embodiment of the present disclosure can be blended with fibers, resins, or liquids (e.g., water, organic solvents, etc.) and used as a raw material for producing deodorizing products. Examples of uses of the deodorizing product include deodorizing liquid, deodorizing fiber, deodorizing resin composition, deodorizing fabric, and deodorizing filter material.

[0014] As a result of extensive research, the present inventors have found that the above-described configuration makes it possible to provide a gas adsorbent containing a metal organic framework capable of adsorbing various gases that cause malodors. Specifically, the present inventors conducted detailed research and found that a metal organic framework that combines at least one metal atom selected from the group consisting of Zr, Zn, Al, and Mg with an organic ligand having at least one group selected from the group consisting of a carboxy group and a carboxylate group, and that includes partial defects in the organic ligand, has excellent gas adsorption performance. With this combination, the metal organic framework has pores of appropriate size and excellent uniformity, and the specific surface area of ​​the metal organic framework is large. Furthermore, the defects in the organic ligand function as gas adsorption sites, stabilizing the gas within the pores. Therefore, it is presumed that the gas adsorbent according to the present disclosure has excellent gas adsorption performance.

[0015] The metal organic framework used in the gas adsorbent according to the present disclosure has high adsorption performance for acetic acid gas contained in human body odor (e.g., sweat odor, etc.) and also has high adsorption performance for other acidic gases, basic gases, aldehyde gases, and VOC gases. The metal organic framework is a white powder.

[0016] The gas adsorbent is preferably used to adsorb malodorous gases. In the present disclosure, "malodorous gas" refers to a gas that humans find unpleasant. "Gas that humans find unpleasant" refers to a gas that is evaluated, on average, on the negative side (unpleasant side) of the median value of 0 in a nine-point pleasantness / unpleasantness scale in a sensory test of gases. When a gas adsorbent is used to adsorb malodorous gases, the malodorous gases are easily adsorbed by the gas adsorbent. As a result, the gas adsorbent of the present disclosure can remove malodorous gases.

[0017] <Metal Organic Framework> The gas adsorbent according to the present disclosure includes a metal organic framework. The metal organic framework has at least one metal atom selected from the group consisting of Zr, Zn, Al, and Mg, and an organic ligand having at least one group selected from the group consisting of a carboxy group and a carboxylate group, and includes partial defects in the organic ligand. The metal organic framework according to the present disclosure is also referred to as a porous organometallic complex. "Porous" refers to a structure having a plurality of pores. The plurality of pores may or may not be interconnected.

[0018] The metal atom contained in the metal organic framework may be of only one type, or may be of two or more types. From the viewpoint of gas adsorption properties, the metal atom contained in the metal organic framework is preferably at least one type selected from the group consisting of Zr and Zn, and more preferably Zr. Among these, from the viewpoint of gas adsorption properties, the metal organic framework preferably has a metal cluster, more preferably has a zirconium cluster, and particularly preferably has a zirconium oxycluster.

[0019] The organic ligand used in the metal-organic framework is not particularly limited as long as it has at least one group selected from the group consisting of a carboxy group and a carboxylate group and can form the metal-organic framework. The organic ligand is preferably a polycarboxylic acid or a polycarboxylic acid anion having an ethylene skeleton or a benzene skeleton. The expression "polycarboxylic acid or an anion thereof" (and similar expressions, such as "terephthalic acid or an anion thereof") encompasses only a polycarboxylic acid, only an anion of a polycarboxylic acid, or both a polycarboxylic acid and an anion thereof. A "polycarboxylic acid" is a compound containing two or more carboxy groups in one molecule. When the organic ligand is a polycarboxylic acid or a polycarboxylic acid anion having an ethylene skeleton or a benzene skeleton, the gas adsorbent of the present disclosure has superior adsorption properties.

[0020] Examples of polycarboxylic acids having an ethylene skeleton include, but are not limited to, fumaric acid and maleic acid. Examples of polycarboxylic acids having a benzene skeleton include, but are not limited to, phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,3,5-benzenetricarboxylic acid, and 4,4'-biphenyldicarboxylic acid. Examples of organic ligands having a carboxylate group include anions of the above polycarboxylic acids. Among these, from the viewpoints of the formability of the metal-organic framework and gas adsorption properties, the organic ligand is preferably a dicarboxylic acid compound or a biscarboxylate ion compound, more preferably a dicarboxylic acid or its dianion composed of a carboxy group and a divalent hydrocarbon group, even more preferably a dicarboxylic acid or its dianion composed of a carboxy group and a divalent aromatic hydrocarbon group, and particularly preferably terephthalic acid or a terephthalic acid dianion. The term "divalent hydrocarbon group" refers to a hydrocarbon group obtained by removing two functional groups from an organic ligand having two functional groups capable of coordinating to a metal ion. The term "divalent aromatic hydrocarbon group" refers to an aromatic hydrocarbon group obtained by removing two functional groups from an organic ligand having two functional groups capable of coordinating to a metal ion. From the viewpoints of formability of a metal organic framework and gas adsorption properties, it is preferable that the metal atom in the metal organic framework is Zr, and the organic ligand is a dicarboxylic acid compound or a biscarboxylate ion compound, and it is particularly preferable that the metal atom in the metal organic framework is Zr, and the organic ligand is terephthalic acid or a terephthalic acid dianion.

[0021] The content of the organic ligand in the metal organic framework can be appropriately adjusted according to the type and amount of the metal atom. In particular, from the viewpoint of gas adsorption properties, the molar ratio of the metal atom to the organic ligand is preferably metal atom:organic ligand=6:0.01 to 6:5.99, more preferably metal atom:organic ligand=6:1.00 to 6:5.70, even more preferably metal atom:organic ligand=6:3.00 to 6:5.50, even more preferably metal atom:organic ligand=6:3.00 to 6:5.30, even more preferably metal atom:organic ligand=6:3.50 to 6:5.00, even more preferably metal atom:organic ligand=6:4.00 to 6:4.90, and particularly preferably metal atom:organic ligand=6:4.50 to 6:4.80.

[0022] The metal organic framework includes partial defects in the organic ligands. "Partial defects in the organic ligands" means that some of the organic ligands constituting the metal organic framework are missing. The sites where the organic ligands are missing function as gas adsorption sites, thereby improving gas adsorption performance.

[0023] The defect ratio of the organic ligands may be appropriately selected depending on the type of metal-organic framework, but may be, for example, 1 to 99%, 5 to 80%, or 20 to 50%. The defect ratio can be calculated using the following formula: Defect ratio = 100 × [(number of ligands in MOF without defects) - (number of ligands in MOF with defects)] / (number of ligands in MOF without defects).

[0024] The number of ligands in a MOF can be measured by a method using thermogravimetric analysis described in Chemistry of Materials 2016, 28, 3749-3761. Specific measurement conditions are as described in the Examples below.

[0025] The defect ratio of the organic ligand can be increased, for example, by reducing the ratio of the ligand during synthesis of the metal organic framework, or by adding a monocarboxylic acid as a modulator to the reaction system.

[0026] In the case of a metal-organic structure in which the metal atom is Zr and the organic ligand is terephthalic acid or an anion thereof, the molar ratio of Zr to terephthalic acid or an anion thereof is preferably 6:0.01 or more and less than 6.00, more preferably 6:1.00 or more and 5.70 or less, even more preferably 6:3.00 or more and 5.50 or less, even more preferably 6:3.00 or more and 5.30 or less, even more preferably 6:3.50 or more and 5.00 or less, even more preferably 6:4.00 or more and 4.90 or less, and even more preferably 6:4.50 or more and 4.80 or less.

[0027] The metal-containing structure preferably has a structure represented by the following formula (A): [Zr ６ (OH) ４ O ４ (bdc) ｎ L ｘ (A) (wherein, bdc is terephthalic acid or an anion thereof, n is 0.01 or more and less than 6, L is a ligand other than bdc, and x is an arbitrary number of 0 or more).

[0028] When n in formula (A) is 6, there is no partial defect of the organic ligand. n in formula (A) is preferably 3.0 or more and 5.7 or less, more preferably 3.0 or more and 5.5 or less, even more preferably 3.5 or more and 5.0 or less, and particularly preferably 3.5 or more and 4.80 or less.

[0029] L in formula (A) is any ligand that may be present at the defect site of bdc. Examples of L include a carbonyl group-containing ligand, a nitrogen-containing ligand, OH, and H. ２ Examples include O.

[0030] Examples of carbonyl-containing ligands include carbonyl, acyl, ketone, aldehyde, carboxylate, ester, amide, and β-diketonate ligands. Examples of carboxylate ligands include formate, acetate, and propionate ligands.

[0031] Nitrogen-containing ligands include, for example, ammonium ligands and cyanide ligands.

[0032] The number of L in formula (A) (that is, x in formula (A)) varies depending on the type of ligand, but the maximum number is the number of ligands that can fill all the vacant portions of bdc.

[0033] The nitrogen content (e.g., compounds having nitrogen atoms) in the metal-organic framework is preferably low. In recent years, there has been a demand for gas adsorbents that can be kneaded into resins and gas adsorbents that can be processed into fibers. The inventors' studies have revealed that metal-organic frameworks having nitrogen-containing groups in their ligands discolor polyester resins. After extensive investigation into the cause of this discoloration, they speculated that the nitrogen-containing groups promote decomposition of the polyester resin, and the resulting quinone structure shifts the absorption wavelength of the polyester resin toward visible light. In contrast, by reducing the nitrogen content in the metal-organic framework, decomposition of the resin during heating and mixing with an ester resin and molding can be suppressed, and resin discoloration can also be suppressed. Therefore, the metal-organic framework according to the present disclosure can be applied to resins (e.g., polyester resins) that could not be used in the past due to hydrolysis or discoloration. As a result, the processing applications as a gas adsorbent are greatly expanded.

[0034] From the viewpoint of suppressing resin decomposition and resin coloration, the content of nitrogen atoms in the metal organic framework is preferably 5% by mass or less, more preferably less than 5% by mass, even more preferably 2.0% by mass or less, particularly preferably 0.5% by mass or less, and most preferably 0.1% by mass or less, relative to the total mass of the metal organic framework. The lower limit of the content of nitrogen atoms in the metal organic framework is 0% by mass. Note that the "total mass of the metal organic framework" refers to the weight of the metal organic framework after vacuum drying at 120°C for 6 hours. When a compound having a nitrogen atom is used as a reaction substrate or solvent (particularly a solvent) for the metal organic framework, contamination of the metal organic framework and the gas adsorbent with nitrogen atoms is observed. Examples of the compound having a nitrogen atom used in the synthesis of the metal organic framework include compounds containing a nitrogen-containing functional group (e.g., an amino group, an amide group, an imide group, etc.). Specific examples of compounds having a nitrogen atom include N,N-dimethylformamide (DMF), N,N-diethylformamide (DEF), N,N-dimethylacetamide (DMAc), ammonia, and triethylamine.

[0035] The method for producing the metal organic framework used in the present disclosure is not particularly limited, and known methods and methods based on these known methods can be suitably used.

[0036] The metal organic framework may be contained alone or in combination of two or more types. The content of the metal organic framework in the gas adsorbent is preferably 10% by mass or more, and more preferably 50% by mass or more, relative to the total amount of the gas adsorbent. The content of the metal organic framework may be 100% by mass. That is, the gas adsorbent may consist solely of the metal organic framework. The content of the metal organic framework may be 50% by mass or less, or 30% by mass or less.

[0037] The maximum pore diameter of the metal-organic framework is preferably 0.2 nm to 10.0 nm, and more preferably 0.4 nm to 1.5 nm. The "maximum pore diameter" refers to the maximum diameter of the pores formed in the metal-organic framework. The maximum pore diameter is measured using a nitrogen adsorption measurement device, and may be measured using, for example, a model "AUTOSORB-1" (manufactured by Anton Paar).

[0038] The metal organic framework is preferably in the form of particles, and the primary particle size of the particles is preferably 0.01 μm to 3.0 μm, more preferably 0.02 μm to 2.0 μm, and even more preferably 0.03 μm to 1.5 μm.

[0039] The primary particle size is measured by the following method. First, the metal-organic framework is observed at an appropriate magnification using a semi-in-lens scanning electron microscope (SEM) (product name "S-4800", manufactured by Hitachi High-Technologies Corporation). Particles are identified based on the obtained SEM image. In the SEM image at a magnification at which a single particle can be observed, the diameter of the longest part of the particle (hereinafter also referred to as "longest diameter") is measured. The longest diameters of 100 particles are measured, and the average of the measured values ​​is taken as the primary particle size.

[0040] The BET specific surface area per mass of the metal organic framework is not particularly limited, and is preferably 500 m ２ / g to 2000m ２ / g, and 600m ２ / g~1600m ２ / g, and 700m ２ / g~1500m ２ The method for measuring the BET specific surface area per mass of the metal organic framework is the same as the method described in the Examples.

[0041] The half width of the main peak (peak width at half the peak height) in the spectrum obtained by measuring the metal organic framework by powder X-ray diffraction measurement (PXRD) is preferably 0.4° or less, more preferably 0.35° or less, and particularly preferably 0.3° or less.

[0042] The gas adsorbent according to the present disclosure may contain components other than the metal organic framework. The other components are not particularly limited, and examples thereof include known deodorizers (e.g., acidic gas deodorizers, basic gas deodorizers, sulfur-based gas deodorizers, aldehyde-based gas deodorizers, and ketone-based gas deodorizers), antibacterial agents, antifungal agents, antiviral processing agents, antiallergens, defoaming agents, colorants, preservatives, viscosity modifiers, fragrances, surfactants, water, solvents, preservatives, moisturizers, thickeners, pH adjusters, bleaching agents, chelating agents, water-soluble salts, and oils.

[0043] The gas adsorbent according to the present disclosure is preferably used to adsorb acidic gases. In other words, when the gas adsorbent is used to adsorb malodorous gases, the malodorous gases are preferably acidic gases. An "acidic gas" is a gas of molecules that have free protons and exhibit volatility. Examples of acidic gases include carboxylic acids (e.g., formic acid, acetic acid, propionic acid, butyric acid, valeric acid, isovaleric acid, etc.), hydrogen halides (e.g., hydrogen chloride, hydrogen bromide, etc.), inorganic acids (e.g., carbonic acid, nitric acid, sulfuric acid, etc.), and acidic gases (e.g., hydrogen sulfide, etc.). In particular, the gas adsorbent according to an embodiment of the present disclosure is more preferably used to adsorb carboxylic acids and hydrogen sulfide. The gas adsorbent according to an embodiment of the present disclosure is particularly preferably used to adsorb acetic acid gas. That is, the gas adsorbent according to the present disclosure is preferably an adsorbent for acidic gases, more preferably an adsorbent for acetic acid gas.

[0044] The gas adsorbent according to the present disclosure is also preferably used to adsorb basic gases, aldehyde gases, or VOC (Volatile Organic Compounds) gases.

[0045] A "basic gas" is a gas of molecules that have an unshared electron pair and exhibit volatility. Examples of basic gases include ammonia, trimethylamine, pyridine, skatole, and hydrazine.

[0046] An "aldehyde gas" is a molecular gas that has an aldehyde group (-CHO) and exhibits volatility. Examples of aldehyde gases include formaldehyde, nonenal, acetaldehyde, propionaldehyde, normal butyraldehyde, isobutyraldehyde, normal valeraldehyde, and isovaleraldehyde.

[0047] "VOC gas" refers to organic compounds that have evaporated into the air, and refers to gases resulting from the evaporation of substances classified as highly volatile organic compounds (VVOCs), volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), or particulate organic compounds (POMs) according to the classification method defined by the World Health Organization (WHO). More preferably, it refers to gases resulting from the evaporation of highly volatile organic compounds (VVOCs) and volatile organic compounds (VOCs). Examples of VOC gases include toluene, styrene, benzene, ethyl acetate, methyl mercaptan, dichloromethane, ethanol, methyl ethyl ketone, trichloroethane, xylene, limonene, formaldehyde, acetaldehyde, paradichlorobenzene, ethylbenzene, chlorpyrifos, di-n-butyl phthalate, tetradecane, di-n-ethylhexyl phthalate, diazinon, fenobucarb, and L-nicotine.

[0048] The gas adsorbent according to the present disclosure is also preferably used to adsorb carbon dioxide or indole.

[0049] In terms of adsorption capacity, the gas adsorbed by the gas adsorbent may be acetic acid gas, and the adsorption capacity of acetic acid gas is not particularly limited, but is preferably 40 mL / g or more, more preferably 45 mL / g or more, and even more preferably 50 mL / g or more. When the gas adsorption capacity of the gas adsorbent is 40 mL / g or more, the gas adsorbent of the present disclosure can more effectively remove malodorous gases.

[0050] The adsorption capacity of the gas adsorbent for a basic gas is not particularly limited, but is preferably 20 mL / g or more, more preferably 25 mL / g or more, and even more preferably 30 mL / g or more. In terms of the adsorption capacity, the gas adsorbed by the gas adsorbent may be ammonia gas or trimethylamine gas.

[0051] The adsorption capacity of the gas adsorbent for aldehyde gases is not particularly limited, but is preferably 0.5 mL / g or more, more preferably 1.0 mL / g or more, and even more preferably 1.5 mL / g or more. The gas adsorbed by the gas adsorbent in terms of the adsorption capacity may be formaldehyde gas, acetaldehyde gas, or nonenal.

[0052] The adsorption capacity of the gas adsorbent for VOC gas is not particularly limited, but is preferably 5 mL / g or more, more preferably 10 mL / g or more, and even more preferably 15 mL / g or more. In terms of the adsorption capacity, the gas adsorbed by the gas adsorbent may be toluene gas.

[0053] In this disclosure, "adsorption capacity" refers to the maximum amount of a specific gas that a gas adsorbent can adsorb. In other words, "adsorption capacity" refers to the adsorption capacity of both physical and chemical adsorption mechanisms.

[0054] In the present disclosure, the gas adsorption capacity is measured by the method described in the Examples below.

[0055] When the gas adsorbent is used in combination with a polyester resin, the reduction rate represented by the following formula (1) is preferably 50% or less. Formula (1): Reduction rate = 100 × {(weight average molecular weight of heated product of polyester resin alone) - (weight average molecular weight of heated product of mixture) / (weight average molecular weight of heated product of polyester resin alone)} In formula (1), the heated product of the polyester resin alone refers to a product obtained by heating the polyester resin alone at 280°C for 1 hour. The heated product of the mixture refers to a product obtained by heating a mixture consisting of 80 parts by mass of the polyester resin and 20 parts by mass of the gas adsorbent at 280°C for 1 hour. When the reduction rate represented by formula (1) is 50% or less, the gas adsorbent according to the present disclosure can further suppress discoloration and decomposition of the polyester resin by, for example, kneading it into the polyester resin. From the viewpoint of further suppressing discoloration and decomposition of the polyester resin, the reduction rate is more preferably 25% or less, even more preferably 18% or less. The reduction rate may be 10% or more.

[0056] <Applications> The gas adsorbent according to the present disclosure can be used for various applications such as a deodorizer. The gas adsorbent according to the present disclosure can be blended with fibers, resins (including recycled resins), liquids (for example, water, organic solvents, etc.), and can be used as a raw material for producing deodorizing products, etc. In particular, as described above, the gas adsorbent according to the present disclosure can be suitably used as a gas adsorbent for resin kneading, and can be more suitably used as a gas adsorbent for polyester resin kneading.

[0057] The gas adsorbent according to the present disclosure can be suitably used as a kneaded yarn, a textile product, or a resin composite (i.e., a resin material in which the gas adsorbent is kneaded into the resin). Furthermore, the gas adsorbent according to the present disclosure suppresses discoloration and decomposition of the polyester resin during mixing and / or contact, and therefore can be particularly suitably used in polyester resin kneaded yarn, polyester resin textile products, or polyester resin composites. The gas adsorbent according to the present disclosure can also be suitably used, for example, in a processing liquid for gas adsorption or a resin composition (i.e., a mixture containing the gas adsorbent according to the present disclosure and a resin other than a resin composite), etc.

[0058] The resin composite or resin composition according to the present disclosure preferably comprises a gas adsorbent according to the present disclosure and a resin (including recycled resin), and more preferably comprises a gas adsorbent according to the present disclosure and a polyester resin.

[0059] The method for producing the resin composite or resin composition is not particularly limited, and examples thereof include a method in which the gas adsorbent and a resin are mixed together and then molded, and a method in which pelletized resin containing a high concentration of the gas adsorbent is prepared in advance, and the pelletized resin is mixed with another resin and then molded. Molding methods include injection molding, extrusion molding, inflation molding, and vacuum molding.

[0060] The resin constituting the resin composite or resin composition is not particularly limited, and examples thereof include polyester resin, polyurethane resin, polyolefin resin, polyamide resin, polyether resin, acrylic resin, acrylonitrile butadiene styrene (ABS resin), nylon, polystyrene resin, polycarbonate resin, vinyl chloride resin, etc. Among these, polyester resin is preferably used.

[0061] The content of the gas adsorbent in the resin composite or resin composition is preferably 0.1% by mass to 50% by mass, more preferably 0.2% by mass to 35% by mass, and particularly preferably 0.5% by mass to 25% by mass, relative to the total amount of the resin composite or resin composition.

[0062] The resin composite or resin composition may contain additives, such as pigments, dyes, antioxidants, light stabilizers, antistatic agents, foaming agents, impact-resistant strengthening agents, glass fibers, moisture-proofing agents, thickeners, known deodorizers (e.g., acidic gas deodorizers, basic gas deodorizers, sulfur-based gas deodorizers, aldehyde-based gas deodorizers, and ketone-based gas deodorizers), antibacterial agents, antifungal agents, antiviral processing agents, antiallergens, defoaming agents, colorants, preservatives, viscosity modifiers, fragrances, surfactants, preservatives, moisturizers, water-soluble salts, and oils.

[0063] The resin composite or resin composition according to the present disclosure can be applied to a variety of products requiring deodorizing properties, such as home appliances (e.g., air purifiers, refrigerators, air conditioners, etc.), general household items (e.g., trash cans, drainers, plastic wrap, sponges, etc.), nursing care products (e.g., portable toilets, etc.), housing materials (e.g., wallpaper, toilet bowls, toilet seats, kitchen counters, ventilation fan filters, paints, etc.), vehicle interiors, pet products, and daily necessities.

[0064] The gas adsorbent according to the present disclosure has a high gas adsorption capacity and can therefore be applied to processing liquids (e.g., deodorizing processing liquids, etc.). The processing liquid is applied to or impregnated into yarn, textile products, wood products, resin products, metal products, etc. The processing liquid preferably contains a dispersion medium, a dispersant, and an adhesive in addition to the gas adsorbent. Examples of the dispersion medium include organic solvents (e.g., alcohols, ketones, esters, hydrocarbons, etc.) and water.

[0065] When the dispersion medium is water, examples of the dispersant include polycarboxylic acid dispersants, naphthalenesulfonic acid-formalin condensation dispersants, polyethylene glycol, alkylsulfonic acid dispersants, quaternary ammonium dispersants, higher alcohol alkylene oxide dispersants, polyphosphoric acid dispersants, etc. When the dispersion medium is an organic solvent, examples of the dispersant include polycarboxylic acid alkyl ester dispersants, polyether dispersants, polyalkylamine dispersants, polyhydric alcohol ester dispersants, alkylpolyamine dispersants, etc.

[0066] Examples of adhesives include novolac or resol type phenolic resins, alkyd resins, aminoalkyd resins, acrylic resins, vinyl chloride resins, vinylidene chloride resins, silicone resins, fluororesins, epoxy resins, urethane resins, saturated polyester resins, and melamine resins.

[0067] The content of the gas adsorbent in the processing liquid is preferably 0.1 mass % to 50 mass %, more preferably 0.2 mass % to 30 mass %, and even more preferably 0.3 mass % to 20 mass %, relative to the total amount of the processing liquid.

[0068] The gas adsorbent according to the present disclosure can be suitably used in kneaded yarn or textile products. Suitable textile products include textile products processed from the kneaded yarn, and textile products in which the gas adsorbent is attached to the surface of yarn, cloth, or the like. These can be suitably used as deodorizing fibers or deodorizing fabrics.

[0069] The method for producing a kneaded yarn or a textile product using the gas adsorbent according to the present disclosure is not particularly limited, and examples include a method in which the gas adsorbent according to the present disclosure is kneaded into a textile raw material and then spun, and a method in which a deodorizing liquid containing the gas adsorbent according to the present disclosure is applied to a fiber (for example, a spun chemical fiber or natural fiber) and then dried.

[0070] The fibers used in the present disclosure are not particularly limited, and examples thereof include chemical fibers (e.g., polyester resin, polyurethane resin, nylon, rayon, acrylic resin, vinylon, polypropylene, polyethylene, etc.), natural fibers (e.g., cotton, hemp, silk, wool, etc.), and inorganic fibers (e.g., glass fiber, carbon fiber, alumina fiber, metal fiber, etc.). These fibers may be used alone or in combination of two or more. Among these, polyester resin is preferred.

[0071] The content of the gas adsorbent in the kneaded yarn is preferably 0.1% by mass to 5.0% by mass, more preferably 0.2% by mass to 3.0% by mass, and particularly preferably 0.5% by mass to 2.0% by mass, relative to the total amount of the kneaded yarn.

[0072] Examples of textile products include underwear, stockings, socks, masks, futons, futon covers, cushions, blankets, carpets, curtains, sofas, car seats, air filters, air purifier filters, air conditioner filters, and nursing care clothing.

[0073] The gas adsorbent according to the present disclosure has a high adsorption capacity for malodorous gases and is therefore suitable for use in deodorizing fabrics. The fabric may be a woven fabric, a nonwoven fabric, or a combination thereof.

[0074] The method for producing the deodorizing fabric is not particularly limited, and examples thereof include a method of weaving the deodorizing fiber, a method of producing a nonwoven fabric using the deodorizing fiber by a known method, or a method of applying a deodorizing liquid containing the gas adsorbent according to the present disclosure to a fabric and drying it.

[0075] The content of gas adsorbent in the deodorizing fabric is ２ Preferably, the amount is 0.1 g to 5.0 g, more preferably 0.2 g to 4.0 g, and particularly preferably 0.3 g to 3.0 g.

[0076] The gas adsorbent according to the present disclosure has a high adsorption capacity for malodorous gases, and therefore can be suitably applied to deodorizing filter media.The method for producing deodorizing filter media is not particularly limited, and examples thereof include a method of applying a deodorizing treatment liquid containing the gas adsorbent according to the present disclosure to a substrate and drying it, or a method of producing a deodorizing filter media using the deodorizing fiber or deodorizing fabric.The substrate is not particularly limited as long as it has holes that allow filtration, and examples thereof include fiber, ceramic, or metal.In addition, the substrate may have a honeycomb structure.A honeycomb structure refers to a structure in which the cross section is in the form of continuous cells, and the shape of the cells is not particularly limited as long as it is polygonal.

[0077] The content of gas adsorbent in the deodorizing filter material is ２ It is preferably 0.1 g to 40 g, more preferably 0.5 g to 35 g, and even more preferably 1.0 g to 30 g.

[0078] The deodorizing filter medium can be applied to a variety of products, such as air filters, air purifier filters, air conditioner filters, drainers, water purifiers, etc.

[0079] The present disclosure will be specifically described below based on examples. However, the present disclosure is not limited to these examples. In the following, "parts" and "%" mean "parts by mass" and "% by mass", respectively, unless otherwise specified.

[0080] <Reagents> The reagents used in the examples are as follows: Zirconium oxychloride octahydrate (ZrOCl ２ ・8H ２ O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Acetic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Sodium carbonate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Terephthalic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) Sodium hydroxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Ethanol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) ZrCl ４ (Fujifilm Wako Pure Chemical Industries, Ltd.) Dimethylformamide (Fujifilm Wako Pure Chemical Industries, Ltd.) Concentrated hydrochloric acid (Fujifilm Wako Pure Chemical Industries, Ltd.) Methanol (Fujifilm Wako Pure Chemical Industries, Ltd.)

[0081] <Method for Quantifying Ligand Defects> Thermogravimetric analysis (TG-DTA) was performed using a NETZSCH STA 2500 (NETZSCH Japan). Measurements were performed in air at temperatures between 30°C and 700°C, with a heating rate of 5°C / min. The amount of ligand defects was measured using the graph obtained by TG-DTA according to the method described in Chemistry of Materials 2016, 28, 3749-3761, Supporting Information 3.4. Specifically, the point where the TG graph flattens out near 350°C to 400°C (TGA plateau) was read, and the point where the graph flattens out near 500°C to 700°C was normalized to 100.0% to determine the TGA plateau value (%). The amount of ligand defects was calculated by substituting the obtained value into Equations (20) and (21) in Supporting Information 3.4.4 of the same paper.

[0082] (Example 1: Synthesis of metal organic framework (UiO-66)) <Preparation of metal cluster solution> 4.64 g (14.4 mmol) of ZrOCl was added to 29.4 g of pure water. ２ ・8H ２ O and 18.9 g of acetic acid were added and stirred for 24 hours at 50° C. Sodium carbonate was then added to the solution and stirred, and the pH (25° C.) was adjusted to 4.0 to 5.0 to prepare a metal cluster solution.

[0083] <Preparation of Organic Ligand Solution> 2.85 g (17.1 mmol) of terephthalic acid and 23.4 g (1.50 mol / L) of aqueous sodium hydroxide solution were added to 26.2 g of pure water, and the mixture was stirred at 80° C. for 30 minutes to prepare an organic ligand solution.

[0084] <Synthesis of Metal-Organic Framework> At room temperature (25°C, the same applies below), 19.6 g of organic ligand solution was added dropwise to 27.0 g of metal cluster solution while stirring. Then, 20.2 g of ethanol was added, and the mixture was stirred at 40°C for 1 hour. After solid-liquid separation by centrifugation, the solid was collected and washed three times with 50 mL of water, and then heated and dried at 80°C overnight to obtain the metal-organic framework UiO-66 (white, particulate) of Example 1. As a result of thermogravimetric analysis (Fig. 1), the number of ligand defects in the metal-organic framework UiO-66 was 1.24, and [Zr ６ (OH) ４ O ４ (bdc) ４．７６ (ligand deficiency ratio: about 20.7%) (bdc represents terephthalate dianion).

[0085] <Acetic Acid Gas Adsorption Capacity Evaluation Test> Approximately 20 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume became 3 L. Then, acetic acid gas was introduced into the bag so that the acetic acid gas concentration became 1000 ppm. 120 minutes after the completion of the injection of acetic acid gas, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The acetic acid gas adsorption capacity of each sample was calculated using the following formula (3A). The results are shown in Table 1. Formula (3A): Acetic acid gas adsorption capacity (mL / g) = [{1000 (ppm) - measured amount of residual gas (ppm)} × 3,000 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0086] <Isovaleric Acid Gas Adsorption Capacity Evaluation Test> Approximately 5 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume became 1.5 L. Isovaleric acid gas was then introduced into the bag so that the isovaleric acid gas concentration became 100 ppm. 120 minutes after the completion of the injection of isovaleric acid gas, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The isovaleric acid gas adsorption capacity of each sample was calculated using the following formula (3B). The results are shown in Table 2. Formula (3B): Isovaleric acid gas adsorption capacity (mL / g) = [{100 (ppm) - measured amount of residual gas (ppm)} × 1,500 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0087] <Ammonia Gas Adsorption Capacity Evaluation Test> Approximately 10 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume was 3 L. Ammonia gas was then introduced into the bag so that the ammonia gas concentration was 500 ppm. 120 minutes after the completion of the ammonia gas injection, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The ammonia gas adsorption capacity of each sample was calculated using the following formula (3C). The results are shown in Table 3. Formula (3C): Ammonia gas adsorption capacity (mL / g) = [{500 (ppm) - residual gas amount (ppm)} × 3,000 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0088] <Trimethylamine Gas Adsorption Capacity Evaluation Test> Approximately 10 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume was 3 L. Trimethylamine gas was then introduced into the bag so that the trimethylamine gas concentration was 250 ppm. 120 minutes after the completion of the injection of trimethylamine gas, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The trimethylamine gas adsorption capacity of each sample was calculated using the following formula (3D). The results are shown in Table 4. Formula (3D): Trimethylamine gas adsorption capacity (mL / g) = [{250 (ppm) - residual gas amount (ppm)} × 3,000 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0089] <Formaldehyde Gas Adsorption Capacity Evaluation Test> Approximately 20 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume became 3 L. Formaldehyde gas was then introduced into the bag so that the formaldehyde gas concentration became 200 ppm. After 120 minutes had elapsed since the injection of formaldehyde gas was completed, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The formaldehyde gas adsorption capacity of each sample was calculated using the following formula (3E). The results are shown in Table 5. Formula (3E): Formaldehyde gas adsorption capacity (mL / g) = [{200 (ppm) - residual gas amount (ppm)} × 3,000 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0090] <Toluene Gas Adsorption Capacity Evaluation Test> Approximately 10 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume was 3 L. Toluene gas was then introduced into the bag so that the toluene gas concentration was 100 ppm. 120 minutes after the completion of the toluene gas injection, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The toluene gas adsorption capacity of each sample was calculated using the following formula (3F). The results are shown in Table 6. Formula (3F): Toluene gas adsorption amount (mL / g) = [{100 (ppm) - residual gas amount (ppm)} × 3,000 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0091] <Test for evaluating nonenal adsorption performance (sensory test)> (1) Preparation of a nonenal solution with an odor intensity equivalent to 3.5 0.7 mL of 2-nonenal (Fujifilm Wako Pure Chemical Industries, Ltd.) was placed in a 100 mL measuring flask and made up to the desired level with ethanol (Fujifilm Wako Pure Chemical Industries, Ltd.) 0.3 mL of this solution was placed in a new 100 mL measuring flask and made up to the desired level with ethanol to prepare a nonenal solution with an odor intensity equivalent to 3.5.

[0092] (2) Preparation of a nonenal solution equivalent to an odor intensity of 2.0 5 mL of the solution equivalent to an odor intensity of 3.5 in (1) above was placed in a 100 mL measuring flask and diluted with ethanol to prepare a nonenal solution equivalent to an odor intensity of 2.0.

[0093] (3) Sensory Evaluation Test Approximately 10 mg of the metal-organic framework was placed in a 500 mL Erlenmeyer flask. 5 μL of the nonenal solution equivalent to an odor intensity of 3.5 described above in (1) was poured into the same flask. After pouring, the mouth of the volumetric flask was sealed and left to stand for 120 minutes to prepare an evaluation sample. 5 μL of the nonenal solution equivalent to an odor intensity of 2.0 described above in (2) was poured into another 500 mL Erlenmeyer flask. After pouring, the mouth of the volumetric flask was sealed and left to stand for 120 minutes to prepare a judgment odor equivalent to an odor intensity of 2.0. 5 μL of the nonenal solution equivalent to an odor intensity of 3.5 described above in (1) was poured into another 500 mL Erlenmeyer flask. After pouring, the mouth of the volumetric flask was sealed and left to stand for 120 minutes to prepare a blank test sample. After 120 minutes, the evaluators directly smelled the gas phase in the measuring flask, compared it with the odor gas (corresponding to an odor intensity of 2.0) and a blank test, and rated it according to the 6-level odor intensity rating system. The evaluation was performed by three people, and the average of the three people's ratings was calculated as the result. The results are shown in Table 7.

[0094] [Evaluation criteria] 0: No odor 1: Barely detectable odor (detection threshold concentration) 2: Weak odor that can be identified (recognition threshold concentration) 3: Easily detectable odor 4: Strong odor 5: Overpowering odor

[0095] <Acetaldehyde Gas Adsorption Capacity Evaluation Test> Approximately 20 mg of the obtained metal-organic framework was placed as a sample in a bag made of a vinyl alcohol-based polymer film, the bag was sealed, and air was introduced into the bag so that the volume became 3 L. Then, acetaldehyde gas was introduced into the bag so that the acetaldehyde gas concentration became 100 ppm. 120 minutes after the completion of the injection of acetaldehyde gas, the residual gas concentration in the bag (hereinafter also referred to as "residual gas amount") was measured. The acetaldehyde gas adsorption capacity of each sample was calculated using the following formula (3G). The results are shown in Table 8. Formula (3G): Acetaldehyde gas adsorption amount (mL / g) = [{100 (ppm) - residual gas amount (ppm)} × 3,000 (mL) × 1 / 1,000,000] / amount of gas adsorbent used in measurement (g)

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104] As shown in Tables 1 to 8, the MOF of Example 1 exhibited adsorption performance for all gases. Furthermore, the MOF of Example 1 had superior or equivalent adsorption performance compared to existing gas adsorbents specialized for each gas. This indicates that the MOF of Example 1 can function alone as an excellent adsorbent for various types of gases.

[0105] (Reference Example 1: Synthesis of metal organic framework (UiO-66)) In a polytetrafluoroethylene container, 40 mL of dimethylformamide (DMF), 0.62 g of terephthalic acid, and 0.87 g of ZrCl ４ and dissolved by ultrasonic stirring. Next, 0.375 mL of concentrated hydrochloric acid was added to the polytetrafluoroethylene container, and the polytetrafluoroethylene container was sealed with a stainless steel jacket and left to stand in an oven at 120°C for 24 hours. After 24 hours, the container was allowed to cool to room temperature and then the powder was recovered by centrifugation. The supernatant was discarded by decantation and washed with DMF and methanol. After centrifuging again, the mixture was suspended in 80 ml of methanol and stirred overnight at 25°C to replace the solvent with methanol. Next, filtration was performed, and the solid was washed three times with methanol. Thereafter, the mixture was dried overnight at 80°C to obtain the metal organic framework (UiO-66, white, particulate) of Reference Example 1.

[0106] (Reference Example 2: Synthesis of metal organic framework (UiO-66)) In a polytetrafluoroethylene container, 40 mL of DMF, 0.62 g of terephthalic acid, and 0.87 g of ZrCl ４The mixture was added and dissolved by ultrasonic stirring. Next, 0.375 ml of concentrated hydrochloric acid was added to the polytetrafluoroethylene container, and the polytetrafluoroethylene container was sealed with a stainless steel jacket and left to stand in an oven at 120°C for 24 hours. After 24 hours, the mixture was allowed to cool to room temperature and then centrifuged to recover the powder. The supernatant was discarded by decantation and washed with DMF and methanol. The mixture was then dried at 80°C overnight to obtain the metal organic framework (UiO-66) of Reference Example 2.

[0107] (Reference Example 3: Synthesis of metal organic framework (UiO-66)) In a polytetrafluoroethylene container, 40 mL of DMF, 0.62 g of terephthalic acid, and 0.87 g of ZrCl ４ The mixture was added and dissolved by ultrasonic stirring. Next, 0.375 ml of concentrated hydrochloric acid was added to the polytetrafluoroethylene container, and the polytetrafluoroethylene container was sealed with a stainless steel jacket and left to stand in an oven at 120°C for 24 hours. After 24 hours, the mixture was allowed to cool to room temperature and then centrifuged to recover the powder. The supernatant was discarded by decantation and washed with DMF. The mixture was then dried at 80°C overnight to obtain the metal organic framework (UiO-66) of Reference Example 3.

[0108] Comparative Example 1: Synthesis of Metal-Organic Framework (ZIF-8) 35 mL of pure water and 10 g of 2-methylimidazole were added to a beaker and stirred at 25°C for 10 minutes to prepare a 2-methylimidazole aqueous solution. Next, 6 mL of pure water and 0.9 g of zinc nitrate were mixed and stirred at 25°C for 10 minutes to prepare a zinc nitrate aqueous solution. Furthermore, the 2-methylimidazole aqueous solution and the zinc nitrate aqueous solution were mixed and stirred at 25°C for 10 minutes. The obtained reaction liquid was filtered, and the collected solid was washed with pure water. The washed solid was dried at 80°C overnight and then pulverized in a mortar to obtain a metal-organic framework (ZIF-8).

[0109] <Method for analyzing powder X-ray crystallography (PXRD) spectra> PXRD spectra were analyzed using a D8ADVANCE manufactured by Bruker Japan Ltd. The measurement angle was 3° to 50°. The results are shown in Figs. 2 to 4. Fig. 2 is the spectrum of the metal organic framework obtained in Example 1. Fig. 3 is the spectrum of the metal organic framework obtained in Reference Example 1. Fig. 4 is the spectrum of the metal organic framework obtained in Comparative Example 1. In each figure, the vertical axis represents the diffracted X-ray intensity (Counts), and the horizontal axis represents the diffraction angle (2θ (°)).

[0110] <Method for measuring nitrogen atom content> After vacuum drying at 120°C for 6 hours, the nitrogen element content (mass%) was quantified by the Dumas method using a MICRO CORDER JM11 manufactured by J Science Lab Co., Ltd. The results are shown in Table 9.

[0111] <Method for analyzing specific surface area> Approximately 150 mg of the obtained metal-organic framework was sampled and vacuum-dried at 120°C for 6 hours, and then weighed. Using an "AUTOSORB-1" manufactured by Anton Paar, the amount of nitrogen gas adsorption at the boiling point of liquid nitrogen (-195.8°C) was measured at five points in the relative pressure range of 0.1 to 0.3 to create an adsorption isotherm, and the BET specific surface area per mass (m ２ The results are shown in Table 9.

[0112] <Evaluation of Mixing with Polyester Resin> 0.8 g of polyester resin (MA2101M, manufactured by Unitika Ltd.) and 0.2 g of gas adsorbent were mixed to obtain a mixture. The mixture was placed in a magnetic crucible and heated at 280°C for 1 hour using a muffle furnace (FUW252PB, manufactured by Advantec Toyo Co., Ltd.). This resulted in a heated mixture. After cooling, 0.1 g of the heated mixture was cut out and dissolved in a 1:1 (volume ratio) mixed solvent of chloroform and 1,1,1,3,3,3-hexafluoro-2-propanol. The weight average molecular weight Mw of the heated mixture (hereinafter also referred to as "Mw of the heated mixture") was measured using GPC (HLC-8120GPC, manufactured by Tosoh Corporation; column: TSKgel Super HZM-M 6.0 mm I.D. x 15 cm, manufactured by Tosoh Corporation). The Mw of the heated product of the polyester resin alone was measured in the same manner as in measuring the Mw of the heated product of the mixture, except that the mixture was changed to the polyester resin alone. The reduction rate (%) was calculated using the following formula (4). The results are shown in Table 9. Formula (4): Mw reduction rate (%) = 100 × {(Mw of heated product of polyester resin alone) - (Mw of heated product of the mixture) / (Mw of heated product of polyester resin alone)}

[0113]

[0114] As shown in Table 9, the gas adsorbent of Example 1 had a smaller Mw reduction rate of the polyester resin compared to those of Reference Examples 1 to 3 and Comparative Example 1. Therefore, it can be said that the gas adsorbents of the Examples are suitable for use in kneading into polyester resins and the like.

[0115] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A metal organic framework comprising: at least one metal atom selected from the group consisting of Zr, Zn, Al, and Mg; and an organic ligand having at least one group selected from the group consisting of a carboxy group and a carboxylate group, wherein the metal organic framework contains a partial defect in the organic ligand.

2. The metal organic framework according to claim 1, wherein the content of nitrogen atoms is less than 5 mass% relative to the total mass of the metal organic framework.

3. The metal organic framework according to claim 1, wherein the nitrogen atom content is 0.5 mass% or less, based on the total mass of the metal organic framework.

4. The metal organic framework according to claim 1, wherein the nitrogen atom content is 0.1 mass % or less, based on the total mass of the metal organic framework.

5. The metal organic framework according to claim 1, wherein the metal atom is Zr.

6. The metal organic structure according to claim 1, wherein the organic ligand is a polycarboxylic acid or an anion thereof.

7. The metal organic structure according to claim 1, wherein the organic ligand is a polycarboxylic acid having a benzene skeleton or an anion thereof.

8. The metal organic framework according to claim 1, wherein the organic ligand is terephthalic acid or an anion thereof.

9. The metal organic structure according to any one of claims 1 to 8, wherein the metal atom is Zr, the organic ligand is terephthalic acid or an anion thereof, and the molar ratio of the Zr to the terephthalic acid or the anion thereof is 6:0.01 or more and less than 6:

6.

10. The metal organic structure according to claim 9, wherein the molar ratio of Zr to terephthalic acid or its anion is 6:3.00 or more and 5.70 or less.

11. A compound represented by the following formula (A): [Zr ６ (OH) ４ O ４ (bdc) ｎ L ｘ 9. The metal organic structure according to claim 1 , represented by the following formula (A): (wherein bdc is terephthalic acid or an anion thereof, n is 0.01 or more and less than 6, L is a ligand other than bdc, and x is an arbitrary number of 0 or more).

12. The metal organic framework according to claim 11, wherein n in formula (A) is 3.00 or more and 5.70 or less.

13. A gas adsorbent comprising the metal-organic framework of claim 1.

14. The gas adsorbent according to claim 13, for adsorbing malodorous gases.

15. The gas adsorbent according to claim 13, for adsorbing at least one gas selected from the group consisting of acidic gases, basic gases, aldehyde gases and VOC gases.

16. The gas adsorbent according to claim 13, for adsorbing acidic gases, basic gases, aldehyde gases and VOC gases.

17. A kneaded yarn comprising the gas adsorbent of claim 13.

18. A textile product comprising the gas adsorbent of claim 13.

19. A resin composite comprising the gas adsorbent of claim 13.

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