A two-dimensional cyclodextrin polymer material and its preparation method and application

Abstract

The present invention provides a two-dimensional cyclodextrin polymer material, a preparation method, and applications thereof. The two-dimensional cyclodextrin polymer material is prepared using a method comprising the following steps: stirring a self-assembling agent and cyclodextrin molecules in a solvent, allowing the mixture to stand and self-assemble to form a dispersion having a flaky crystal structure; mixing the dispersion with a cross-linking agent, reacting, performing solid-liquid separation, washing, and drying. This method has a simple preparation process, produces a two-dimensional cyclodextrin polymer having a monolayer thickness, and has considerable prospects for industrial application. The present invention also provides a two-dimensional cyclodextrin polymer material and applications thereof.

Description

Technical Field

[0001] The present application relates to the technical field of polymer materials, and in particular to a two-dimensional cyclodextrin polymer material and a preparation method and application thereof. Background Art

[0002] Two-dimensional polymer materials are one of the cutting-edge research directions in the current field of materials science. Studies have shown that by preparing two-dimensional oriented materials, comprehensive performance that is significantly better than that of traditional one-dimensional materials can be obtained. For example, two-dimensional polyaromatic amide constructs two-dimensional network molecules through monomer polycondensation, and its molecular layers are stacked into highly oriented thin film materials of a certain thickness through hydrogen bonding. In theoretical simulations, the material exhibits extremely high mechanical properties, with a tensile modulus of up to 260GPa and an upper strength limit of 12GPa, far exceeding traditional one-dimensional polymer materials. In addition, two-dimensional polymers also have the advantages of low cost and low process threshold, providing a new way to construct lightweight and high-strength functional materials.

[0003] Since its discovery in the late 19th century, cyclodextrins, due to their unique "hydrophobic interior, hydrophilic exterior" structure, have gradually become a research hotspot in supramolecular chemistry and materials science. In recent years, with the advancement of nanotechnology, bioengineering, and green chemistry, cyclodextrin-based functional materials have shown tremendous potential in drug delivery, environmental remediation, separation and purification, catalysis, and other fields. However, traditional cyclodextrin materials suffer from limitations such as poor stability and low mechanical strength, which limit their widespread application. To overcome these limitations, the construction of cyclodextrin into polymeric materials has become a research hotspot. Cyclodextrin polymers are polymer materials composed of multiple cyclodextrin molecules linked by covalent bonds. They not only retain the encapsulation, sustained-release, and catalytic properties of cyclodextrin molecules, but also possess the excellent mechanical strength and chemical stability of polymers, and significantly improve solubility and other aspects. For example, in practical applications, compared to single cyclodextrin molecules, the superior mechanical strength of cyclodextrin polymers ensures shape stability and performance in applications requiring molding, such as the preparation of microspheres and membranes. When preparing sustained-release drug microspheres, cyclodextrin polymer microspheres can maintain structural integrity in vivo, achieving slow drug release. Therefore, cyclodextrin polymers have shown great development potential in the fields of molecular recognition and adsorption, drug delivery and sustained release, environmental protection and catalysis.

[0004] However, due to the molecular structure of cyclodextrin itself, current research on cyclodextrin polymers is still limited to one-dimensional polymer structures, making it difficult to integrate with cutting-edge research on two-dimensional materials. Achieving two-dimensional polymerization of cyclodextrin presents many challenges. For example, cyclodextrin itself is a cyclic structure that does not easily extend on a two-dimensional plane. During polymerization, it may form a three-dimensional network structure rather than a two-dimensional planar structure, resulting in three-dimensional stacking or disordered cross-linking. Therefore, developing a two-dimensional polymerization method suitable for cyclodextrin molecules has become a cutting-edge technology urgently needed in the field of new materials. Summary of the Invention

[0005] This application provides a method for preparing a two-dimensional cyclodextrin polymer material, resulting in a monolayer-thick two-dimensional cyclodextrin polymer. Based on the nanoscale effects brought about by the optimized microstructure of the product, the comprehensive application performance of the cyclodextrin material is expected to be improved. This method has a simple process flow, low cost, good universality, and can be implemented in large-scale industrial production, with broad prospects for industrial application.

[0006] The present application also provides a two-dimensional cyclodextrin polymer material.

[0007] The present application also provides applications of the above-mentioned two-dimensional cyclodextrin polymer material.

[0008] A first embodiment of the present invention relates to a method for preparing a two-dimensional cyclodextrin polymer material, comprising the following steps:

[0009] The self-assembly agent and cyclodextrin molecules are stirred in a solvent, allowed to stand, and self-assembled to form a dispersion having a sheet-like structure crystal; the dispersion is mixed with a cross-linking agent, reacted, solid-liquid separated, washed, and dried to obtain the two-dimensional cyclodextrin polymer material;

[0010] The self-assembly agent includes a surfactant having a C10-C30 hydrophobic chain, and the molar ratio of the surfactant to the cyclodextrin molecule is ≤1:0.95.

[0011] The method for preparing the two-dimensional cyclodextrin polymer material according to the first embodiment of the present invention has at least the following beneficial effects:

[0012] Using a self-assembly agent to induce cyclodextrin molecules to self-assemble in a solvent to form a highly ordered monolayer lamellae, combined with a subsequent crosslinking reaction, a monolayer-thick two-dimensional cyclodextrin polymer material was prepared. This overcomes the technical bottleneck of traditional techniques that have limited the construction of two-dimensional regular structures due to the ring structure of cyclodextrin molecules. In the resulting two-dimensional cyclodextrin polymer, all cyclodextrin molecules are located in the same plane and directly or indirectly connected by covalent bonds, forming an ordered planar structure. The molecular layer thickness is controlled to 0.7-1nm, resulting in a highly regular and thickness-controlled two-dimensional polymer material.

[0013] The carbon number range of the hydrophobic chain of the self-assembling agent plays a key regulatory role in the formation of the cyclodextrin monolayer lamellae structure. The appropriate carbon number can provide effective spatial configuration constraints, inducing the orderly arrangement of cyclodextrin molecules along the plane and promoting the construction of stable monolayer lamellae. If the carbon number is too small, it is difficult to effectively induce the two-dimensional arrangement and form an ordered monolayer structure; if the carbon number is too large, the orderliness of the two-dimensional arrangement may be reduced. In addition, when the molar ratio of the self-assembling agent to the cyclodextrin molecules is too high, the spatial configuration of the supramolecular self-assembly will change, making it difficult to form a two-dimensional crystal structure.

[0014] This method has broad applicability, applicable to a wide range of cyclodextrin molecules and their derivatives. The resulting materials, with their large surface area, uniform lamellar structure, and controlled molecular arrangement, help fully realize the potential and performance advantages of cyclodextrin materials.

[0015] This method has simple process, low cost, can be realized in large-scale industrial production, and has significant application prospects.

[0016] Wherein, the self-assembly agent includes a non-ionic surfactant having a carbon number of C10-C30 and / or an ionic surfactant having a C10-C30 hydrophobic chain.

[0017] Specifically, ionic surfactants include one or more of anionic (RX), cationic (RY), and zwitterionic surfactants (YRX), wherein R is a C10-C30 hydrocarbon group or a C10-C30 heterohydrocarbon group (hydrophobic chain), X is an anionic hydrophilic group, and Y is a cationic hydrophilic group. For example, anionic hydrophilic groups include, but are not limited to, carboxyl groups, carboxylate groups, sulfonic acid groups, sulfonate groups, benzenesulfonic acid groups, benzenesulfonate groups, sulfate groups, sulfate groups, and the like; cationic hydrophilic groups include, but are not limited to, ammonium salt groups and C1-C12 hydrocarbon amine salt groups.

[0018] More specifically, typical and non-limiting examples of nonionic surfactants include sorbitan monooleate and coco-glucoside; typical and non-limiting examples of cationic surfactants include cetyltrimethylammonium bromide and tetradecyltrimethylammonium chloride; typical and non-limiting examples of anionic surfactants include sodium lauryl sulfate, sodium dodecylbenzenesulfonate and N-lauroyl glycine; and typical and non-limiting examples of zwitterionic surfactants include cocamidopropyl betaine.

[0019] According to some embodiments of the present invention, the self-assembly agent includes a surfactant having a C10-C20 hydrophobic chain, such as a non-ionic surfactant having a carbon number of C10-C20, and / or an ionic surfactant having a C10-C20 hydrophobic chain.

[0020] According to some embodiments of the present invention, the cyclodextrin molecule is a ring structure formed by three or more monosaccharide units connected by glycosidic bonds, and the monosaccharide units are selected from one or more of triose, tetroses, pentoses, hexoses, heptoses or their derivatives.

[0021] For example, common cyclodextrin derivatives include cyclodextrins modified with one or more of the following functional groups: C1-C30 alkyl (such as methyl, ethyl), hydroxypropyl, hydroxyl, amino, thiol, carboxyl, carboxylate, aldehyde, C1-C30 hydrocarbon ether, sulfonic acid, sulfonate, sulfonyl, benzenesulfonic acid, benzenesulfonate, azide, silane, phosphate or its salt, nitro, C1-C30 hydrocarbon ester, dipeptide (such as aspartame modification group), tripeptide (such as glutathione modification group), cyano and halogen, wherein the number of functional groups is single substitution to the maximum number of substitutions.

[0022] According to some embodiments of the present invention, the cyclodextrin molecules are selected from one or more of α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, or their derivatives. The basic monosaccharide units of these cyclodextrin molecules are all hexoses (i.e., glucose). The most common molecules contain 6, 7, or 8 glucose units, referred to as α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, respectively. These types of cyclodextrins and their derivatives are readily commercially available. In addition, other cyclodextrin molecules containing 3 or more glucose units can also be synthesized using techniques known in the art, with a common degree of polymerization ranging from 3 to 13 monosaccharide units.

[0023] According to some embodiments of the invention, the molar ratio of the surfactant to the cyclodextrin molecules is 1:0.95-12, for example, 1:0.95, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11 or 1:12.

[0024] According to some specific embodiments of the present invention, the molar ratio of the surfactant to the cyclodextrin molecules is 1:0.95-8.

[0025] According to some embodiments of the present invention, the cross-linking agent is selected from one or more of acyl chloride compounds, acid anhydride compounds, isocyanate compounds, halogenated alkane compounds, halogenated silane compounds, epoxysilane compounds, aminosilane compounds, halogenated epoxy compounds, aldehyde compounds, ester compounds, glycidyl ether compounds, halogenated triazine compounds, nitrile compounds, organic acids or salts thereof, organic bases or salts thereof, unsaturated hydrocarbon compounds, polyhydroxy polymers, polycarbonates, fluorinated polyolefins, and acrylic acid-modified polymers, and the cross-linking agent has multiple functional groups that can react with the cyclodextrin molecules. The cross-linking agent is a substance known in the art that can react with cyclodextrin molecules and is not limited to the types listed.

[0026] Specifically, the cross-linking agent includes but is not limited to the following substances: acid chloride compounds, such as glutaryl chloride, adipoyl chloride, sebacoyl chloride, terephthaloyl chloride, succinyl chloride; acid anhydride compounds, such as glutaric anhydride, maleic anhydride, succinic anhydride, phthalic anhydride, pyromellitic anhydride; isocyanate compounds, such as hexamethylene diisocyanate, isophorone diisocyanate, polyisocyanate, 1,4-phenylene diisocyanate, 2,4-toluene diisocyanate; Ester, 1,5-naphthalene diisocyanate, 4,4'-dicyclohexyl diisocyanate, 4,4'-diphenylmethane diisocyanate, triphenylmethane-4,4',4''-triisocyanate; halogenated alkane compounds, such as dichloromethane; halogenated silane compounds, such as dichlorodimethylsiloxane; epoxy silane compounds, such as 3-(2,3-epoxypropoxy)propyltrimethoxysilane; aminosilane compounds, such as γ-aminopropyltriethylsilane; oxysilanes; halogenated epoxy compounds such as epichlorohydrin; aldehyde compounds such as glutaraldehyde; ester compounds such as diphenyl carbonate; glycidyl ether compounds such as 1,4-butanediol diglycidyl ether; halogenated triazine compounds such as trichlorotriazine; nitrile compounds such as tetrafluoroterephthalonitrile; organic acids or their salts such as citric acid, glutamic acid, malic acid, tartaric acid, muconic acid, maleic acid, glutaric acid, phthalic acid, 2,6-naphthalene diol; Formic acid, tricarballylic acid, trimesic acid, 2,6-naphthalene dicarboxylic acid, aspartic acid, tetrafluoroterephthalic acid, sodium citrate; organic bases such as hexamethylenediamine; unsaturated hydrocarbon compounds such as 1,4-diethynylbenzene; polyhydroxy polymers such as polyethylene glycol and polyvinyl alcohol; polycarbonates such as polypropylene carbonate; fluorinated polyolefins such as polyvinylidene fluoride and polytetrafluoroethylene; acrylic acid modified polymers such as polyethylene glycol monoacrylate and polycyanoacrylate.

[0027] According to some embodiments of the present invention, the molar ratio of the crosslinker to the cyclodextrin molecules is 2-50:1, for example, 2:1, 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, 50:1, to form a moderate crosslinked structure.

[0028] According to some specific embodiments of the present invention, the molar ratio of the cross-linking agent to the cyclodextrin molecules is 2-30:1, or 2-20:1, or 2-10:1.

[0029] According to some embodiments of the present invention, the solvent is selected from at least one of water, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, isopropyl alcohol, chloroform, tetrahydrofuran, and trifluoroacetic acid.

[0030] According to some embodiments of the present invention, the added amount of the surfactant relative to the solvent is 1-600 mg / mL, for example 5-500 mg / mL, or 5-300 mg / mL, or 5-100 mg / mL, or 5-80 mg / mL, more specifically 5 mg / mL, 10 mg / mL, 20 mg / mL, 30 mg / mL, 40 mg / mL, 50 mg / mL, 60 mg / mL, 70 mg / mL or 80 mg / mL.

[0031] According to some embodiments of the present invention, the amount of cyclodextrin molecules added relative to the solvent is 1-2000 mg / mL, or 10-1000 mg / mL, or 10-800 mg / mL, or 10-700 mg / mL, or 10-500 mg / mL, more specifically 10 mg / mL, 20 mg / mL, 30 mg / mL, 40 mg / mL, 50 mg / mL, 100 mg / mL, 150 mg / mL, 200 mg / mL, 250 mg / mL, 300 mg / mL, 350 mg / mL, 400 mg / mL, 450 mg / mL, 500 mg / mL.

[0032] According to some embodiments of the present invention, the stirring temperature is 20-100°C, and the standing temperature is lower than the stirring temperature. For example, the stirring temperature can be 40-90°C, and the standing temperature can be 20-30°C. The present invention does not strictly limit the specific temperature and time of stirring and standing, and can be adjusted according to the solubility of the sample or the processing volume. The stirring time can be several hours or tens of hours to obtain a fully uniform mixing effect; the standing time can be appropriately adjusted according to the volume of the processing solution. When the processing volume is small, it can be several minutes. When the processing volume reaches 0.5L or more, it can be extended to tens of hours or even more than 2 weeks, until self-assembled crystals are stably formed in the system.

[0033] According to some embodiments of the present invention, the step of adding a catalyst to mix before the reaction is further included. The use of a catalyst can be flexibly selected according to the reactivity between the cross-linking agent and the cyclodextrin molecules. The reaction mechanism is a known technology, and the specific type and dosage can be reasonably selected based on experience. For example, the catalyst can be selected from inorganic salts, including but not limited to sodium dihydrogen phosphate, sodium bicarbonate, potassium bicarbonate, potassium dihydrogen phosphate, sodium bisulfite, potassium hydrogen oxalate, sodium hydrosulfide, sodium borohydride, ammonium hydrosulfide, etc., and the amount used can be 5%-15% of the molar amount of the cross-linking agent. For some cross-linking systems with higher reactivity, rapid reaction can be achieved without the need for a catalyst, thereby improving process simplicity.

[0034] According to some embodiments of the present invention, the reaction temperature is 20-150°C, which can be adjusted according to the reactivity of the system. When the reactivity is high, a lower reaction temperature and a shorter reaction time can be used, and a rapid reaction can be achieved even during mixing. When the reactivity is low, a higher reaction temperature and a longer reaction time are required. For example, the reaction can be carried out at a temperature above 100°C for several hours to ensure a sufficient reaction. When the reaction temperature exceeds the boiling point or flash point of the solvent used, reflux treatment is performed during the reaction.

[0035] According to some embodiments of the present invention, the solid-liquid separation is performed by any one of centrifugation, vacuum filtration, mesh filtration, gauze filtration or natural sedimentation.

[0036] According to some embodiments of the present invention, the drying is carried out by any one of heating drying, natural air drying, spray drying, vacuum drying, freeze drying or supercritical drying.

[0037] According to some embodiments of the present invention, the washing is performed with water.

[0038] The second embodiment of the present invention relates to a two-dimensional cyclodextrin polymer material having a layered structure, wherein the layered structure is a planar structure formed by cyclodextrin molecules connected by covalent bonds, the layered structure has a thickness of 0.7-1 nm, and a sheet diameter ≥10 nm.

[0039] In this two-dimensional cyclodextrin polymer, all cyclodextrin molecules are located in the same plane and connected directly or indirectly by covalent bonds, forming an ordered planar structure. The molecular layer thickness is controlled to be 0.7-1 nm, resulting in a highly regular and thickness-controllable two-dimensional polymer material. This material has a large specific surface area, a uniform lamellar structure, and controllable molecular arrangement, which helps fully utilize the performance advantages of cyclodextrin materials. This material can be prepared using a simple method, making it suitable for large-scale application.

[0040] The type of cyclodextrin molecules can be determined by referring to the implementation method of the aforementioned preparation method.

[0041] According to some embodiments of the present invention, the two-dimensional cyclodextrin polymer material satisfies at least one of the following conditions:

[0042] (1) The sheet diameter is 10 nm to 100 μm;

[0043] (2) The layered structure comprises a pore structure, and the pore structure comprises one or more of micropores, mesopores and macropores, wherein the pore diameter of the micropores is less than 2 nm, the pore diameter of the mesopores is 2-50 nm, and the pore diameter of the macropores is greater than 50 nm.

[0044] According to some specific embodiments of the present invention, the pore diameter of the micropores is greater than 0.5 nm and less than 2 nm, and the pore diameter of the macropores is 50-500 nm.

[0045] The third aspect of the present invention relates to the two-dimensional cyclodextrin polymer material obtained by the above-mentioned preparation method, or the application of the above-mentioned two-dimensional cyclodextrin polymer material in the fields of catalysts, functional block materials, drug delivery, gene transport, material separation or purification, and pollutant adsorption or removal.

[0046] Specifically, in the field of catalysts, it can be used as a stable carrier for metal ions, chiral centers, or enzyme factors, and is applied in asymmetric catalysis, aqueous phase reactions, and biomimetic catalysis. The material can also be used as a functional block material, such as in the preparation of aerogels.

[0047] In drug delivery systems, it is particularly suitable for solubilization and encapsulation of poorly water-soluble drugs, sustained-release and controlled-release preparations, targeted delivery systems, local permeability enhancement, and stable release of protein drugs. In the field of gene transport, it can be used for efficient encapsulation and transfection of plasmid DNA, siRNA, or miRNA. In the field of separation and purification, it is suitable for the separation of chiral compounds, capture of drug metabolites, chromatographic stationary phases, or functional membrane materials. As a membrane material, it can separate and purify liquid and gas molecules of different sizes, and at the same time play an isolation role. In the field of pollutant adsorption and removal, the two-dimensional structure helps to expose more active sites and improve the enrichment capacity of organic dyes, heavy metal ions, microplastics, and radionuclides, and is suitable for a variety of application scenarios such as environmental remediation.

[0048] Herein, the term "hydrophobic chain" refers to a molecular chain having a hydrophobic property, including a hydrocarbon group or a heterohydrocarbon group, and its structure can be a straight chain, a branched chain, a cyclic structure, or a combination of at least two of these structures.

[0049] The term "hydrocarbyl" refers to a group consisting solely of carbon and hydrogen atoms, including saturated hydrocarbyl groups (e.g., straight-chain or branched alkyl groups, alkyl-substituted or unsubstituted cycloalkyl groups), unsaturated non-aromatic hydrocarbyl groups (e.g., alkenyl groups, alkynyl groups), and aromatic hydrocarbyl groups (e.g., phenyl groups, naphthyl groups, biphenyl groups, etc.). A "heterohydrocarbyl" group refers to a hydrocarbyl group as defined above in which at least one carbon atom is replaced by a non-carbon atom, wherein the non-carbon atom can be selected from at least one of O, S, N, Se, Si, or Ge, but does not include groups with non-carbon atoms as attachment sites (e.g., alkoxy groups, aryloxy groups, alkylamino groups, arylamino groups, etc.).

[0050] The term "plurality" means two or more.

[0051] The terms "above" and "below" include the stated value itself, whereas "below", "greater than" and "less than" do not include the stated value itself.

[0052] “Approximately” means the error range is mainly within ±5%.

[0053] "Room temperature" refers to 23±2°C.

[0054] Herein, the numerical ranges mentioned include the endpoint values ​​and encompass any sub-ranges within the range, such as the range obtained by any combination of the specifically listed numerical values. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 1. The spherical aberration corrected transmission electron microscope image (left) and selected area electron diffraction spot pattern (right) of the self-assembled crystal of Example 1.

[0056] Figure 2 A photograph of the two-dimensional cyclodextrin polymer powder of Example 1 (left) and a transmission electron microscope image thereof (right, scale bar 100 nm) are shown.

[0057] Figure 3 This is an atomic force microscope image of the two-dimensional cyclodextrin polymer monolayer of Example 1.

[0058] Figure 4 This is a diagram showing the BET pore size test results of the two-dimensional cyclodextrin polymer of Example 1. DETAILED DESCRIPTION

[0059] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0060] Some of the raw materials are described as follows:

[0061] α-Cyclodextrin, CAS number: 10016-20-3.

[0062] β-Cyclodextrin, CAS number: 7585-39-9.

[0063] γ-Cyclodextrin, CAS number: 17465-86-0.

[0064] 6-Amino-6-deoxy-β-cyclodextrin, CAS number: 29390-67-8.

[0065] 6-Mercapto-6-deoxy-β-cyclodextrin, CAS number: 81644-55-5.

[0066] Heptasubstituted sulfobutyl ether-β-cyclodextrin, CAS number: 165133-56-2.

[0067] Hydroxypropyl-γ-cyclodextrin, CAS number: 128446-34-4.

[0068] β-Cyclodextrin dihydrogen phosphate sodium salt, CAS number: 199684-61-2.

[0069] Heptakis(6-amino-6-deoxy)-β-cyclodextrin, CAS number: 30754-24-6.

[0070] Tetradecyltrimethylammonium chloride, CAS number: 4574-04-3.

[0071] Cetyltrimethylammonium bromide, CAS number: 57-09-0.

[0072] Sorbitan monooleate, CAS number: 1338-43-8.

[0073] Cocoyl glucoside, CAS number: 141464-42-8.

[0074] N-Lauroylglycine: CAS number: 7596-88-5.

[0075] Sodium lauryl sulfate, CAS number: 151-21-3.

[0076] Sodium dodecylbenzenesulfonate, CAS number: 25155-30-0.

[0077] In the examples, if specific conditions are not specified, conventional conditions or conditions recommended by the manufacturer were followed. For example, reflux was performed during the reaction to prevent solvent volatilization. All reagents and instruments used, if the manufacturer is not specified, are commercially available conventional products.

[0078] Example 1

[0079] First, 1 gram of hexadecyltrimethylammonium bromide was dissolved in 100 milliliters of water, and 8 grams of β-cyclodextrin was dissolved in 100 milliliters of water. Then, the two were mixed and stirred at 80°C for 12 hours. After stopping the stirring, the mixture was allowed to stand at 25°C for 24 hours. Self-assembled crystals were formed in the mixture. The characterization results are shown in FIG. Figure 1 The resulting self-assembled crystal mixture was mixed with citric acid and sodium dihydrogen phosphate (sodium dihydrogen phosphate was one-tenth the molar amount of citric acid, and the molar ratio of citric acid to β-cyclodextrin was 2:1), and stirred to obtain a uniform system. After reacting at 140°C for 4 hours, the obtained solid was centrifuged and washed with water several times, and then heated and dried to obtain a two-dimensional cyclodextrin polymer powder. The characterization results are shown in FIG. Figures 2 to 4 shown.

[0080] Figure 1The left image shows a spherical aberration-corrected transmission electron microscopy image of a crystalline sample, and the right image shows the corresponding selected-area electron diffraction pattern. The left image shows uniformly arranged, ordered lattice fringes, indicating a highly ordered crystal structure. The right image shows a regular and clear array of single-crystal diffraction spots, confirming the sample's single-crystal structure. Comprehensive analysis suggests a single-layer crystal structure.

[0081] Depend on Figure 2 It can be seen from the TEM image that the obtained material has a thin layer structure and the flake diameter is mainly distributed in the range of 30nm to 1μm. Figure 3 The AFM test results show that the sheet thickness of the material is about 0.8nm, which is consistent with the molecular height of β-cyclodextrin molecules along the direction perpendicular to the ring surface, indicating that the material has a single-molecule layer two-dimensional structure. Figure 4 Pore ​​size measurements show that the material has a microporous structure with pore sizes primarily concentrated around 1.5 nm, and a concentrated and uniform pore size distribution. This structure can be used to separate, purify, and isolate ions, liquids, and gases whose molecular size exceeds the 1.5 nm limit.

[0082] Example 2

[0083] First, 5 grams of hexadecyltrimethylammonium bromide and 50 grams of β-cyclodextrin were dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 60°C for 24 hours. After stirring, the mixture was allowed to stand at 25°C for 48 hours, allowing self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with glutamic acid and sodium dihydrogen phosphate (sodium dihydrogen phosphate was one-tenth the molar amount of glutamic acid, and the molar ratio of glutamic acid to β-cyclodextrin was 2:1). Stirring yielded a homogeneous system. After reacting at 140°C for 4 hours, the resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0084] Example 3

[0085] First, 5 grams of hexadecyltrimethylammonium bromide and 50 grams of α-cyclodextrin were dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 80°C for 14 hours. After stirring, the mixture was allowed to stand at 20°C for 24 hours to allow self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with malic acid and potassium bicarbonate (the molar ratio of potassium bicarbonate to malic acid was one-tenth, and the molar ratio of malic acid to α-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 140°C for 3.5 hours, the resulting solid was washed by multiple centrifugation with ethanol and vacuum dried to obtain a two-dimensional cyclodextrin polymer powder.

[0086] Example 4

[0087] First, 50 grams of tetradecyltrimethylammonium chloride was dissolved in 1 liter of water, and 500 grams of γ-cyclodextrin was dissolved in 800 milliliters of water. The mixture was then mixed and stirred at 80°C for 28 hours. After stirring, the mixture was allowed to stand at 25°C for 48 hours to allow self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with tartaric acid and potassium dihydrogen phosphate (the molar ratio of potassium dihydrogen phosphate to tartaric acid was one-tenth, and the molar ratio of tartaric acid to γ-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 135°C for 5 hours, the resulting solid was washed by multiple centrifugation with water and freeze-dried to obtain a two-dimensional cyclodextrin polymer powder.

[0088] Example 5

[0089] First, 8 grams of sodium dodecyl sulfate was dissolved in 100 milliliters of water, and 30 grams of β-cyclodextrin was dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 80°C for 24 hours. After stirring, the mixture was allowed to stand at 25°C for 24 hours to allow self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with muconic acid and sodium bisulfite (the molar ratio of sodium bisulfite to muconic acid was 1 / 10, and the molar ratio of muconic acid to β-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 145°C for 4.5 hours, the resulting solid was washed with water and ethanol by vacuum filtration multiple times and air-dried to obtain a two-dimensional cyclodextrin polymer powder.

[0090] Example 6

[0091] First, 100 grams of sodium dodecylbenzenesulfonate was dissolved in 1 liter of water, and 400 grams of 6-amino-6-deoxy-β-cyclodextrin was dissolved in 1 liter of water. The mixture was then mixed and stirred at 80°C for 12 hours. After stirring, the mixture was allowed to stand at 25°C for 72 hours, allowing self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with aspartic acid and potassium hydrogen oxalate (the molar ratio of potassium hydrogen oxalate to aspartic acid was 1 / 10, and the molar ratio of aspartic acid to 6-amino-6-deoxy-β-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 130°C for 5 hours, the resulting solid was washed by centrifugation with water and isopropanol multiple times and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0092] Example 7

[0093] First, 8 grams of sodium dodecylbenzenesulfonate was dissolved in 100 milliliters of water, and 30 grams of 6-mercapto-6-deoxy-β-cyclodextrin was dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 60°C for 24 hours. After stirring, the mixture was allowed to stand at 30°C for 96 hours, allowing self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with tricarboxylic acid and sodium bicarbonate (the molar ratio of sodium bicarbonate to tricarboxylic acid was 1 / 10, and the molar ratio of tricarboxylic acid to 6-mercapto-6-deoxy-β-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 150°C for 3 hours, the resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0094] Example 8

[0095] First, 15 grams of sorbitan monooleate and 50 grams of heptasubstituted sulfobutyl ether-β-cyclodextrin were dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 60°C for 24 hours. After stirring, the mixture was allowed to stand at 25°C for 72 hours, allowing self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with trimesic acid and sodium hydrosulfide (sodium hydrosulfide was one-tenth the molar amount of trimesic acid, and the molar ratio of trimesic acid to heptasubstituted sulfobutyl ether-β-cyclodextrin was 2:1). Stirring yielded a homogeneous system. After reacting at 140°C for 4 hours, the resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0096] Example 9

[0097] First, 6 grams of N-lauroylglycine and 60 grams of hydroxypropyl-γ-cyclodextrin were dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 60°C for 24 hours. After stirring, the mixture was allowed to stand at 25°C for 72 hours, allowing self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with 2,6-naphthalene dicarboxylic acid and sodium borohydride (sodium borohydride was one-tenth the molar amount of 2,6-naphthalene dicarboxylic acid, and the molar ratio of 2,6-naphthalene dicarboxylic acid to hydroxypropyl-γ-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 140°C for 3 hours, the resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0098] Example 10

[0099] First, 5 grams of cocoyl glucoside was dissolved in 100 milliliters of water, and 50 grams of β-cyclodextrin dihydrogen phosphate sodium salt was dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 60°C for 24 hours. After stirring, the mixture was allowed to stand at 25°C for 72 hours to allow self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with tetrafluoroterephthalic acid and ammonium bisulfide (ammonium bisulfide was one-tenth the molar amount of tetrafluoroterephthalic acid, and the molar ratio of tetrafluoroterephthalic acid to β-cyclodextrin dihydrogen phosphate sodium salt was 2:1). Stirring yielded a homogeneous system. After reacting at 140°C for 3 hours, the resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0100] Example 11

[0101] First, 10 grams of hexadecyltrimethylammonium bromide was dissolved in 300 milliliters of water, and 50 grams of heptakis(6-amino-6-deoxy)-β-cyclodextrin was dissolved in 200 milliliters of water. The mixture was then mixed and stirred at 90°C for 24 hours. After stirring, the mixture was allowed to stand at 20°C for 240 hours, allowing self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with glutamic acid and sodium dihydrogen phosphate (sodium dihydrogen phosphate was one-tenth the molar amount of glutamic acid, and the molar ratio of glutamic acid to heptakis(6-amino-6-deoxy)-β-cyclodextrin was 2:1). A homogeneous system was obtained by stirring. After reacting at 140°C for 4 hours, the resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0102] Example 12

[0103] First, 8 grams of sodium dodecyl sulfate was dissolved in a mixture of 50 milliliters of water and 50 milliliters of ethanol, and 30 grams of β-cyclodextrin was dissolved in 100 milliliters of water. The mixture was then mixed and stirred at 80°C for 24 hours. After stirring, the mixture was allowed to stand at 25°C for 24 hours to allow self-assembled crystals to form. The resulting self-assembled crystal mixture was then mixed with glutaraldehyde (molar ratio of glutaraldehyde to β-cyclodextrin: 2:1) at room temperature and stirred to obtain a homogeneous system. The resulting solid was washed by multiple centrifugation with water and then dried by heating to obtain a two-dimensional cyclodextrin polymer powder.

[0104] Examples 2-12 can also prepare two-dimensional cyclodextrin polymer powders with a monolayer structure, and their lamellar morphology is similar to that of Example 1. In actual operation, the product sample can be dispersed (by mechanical stirring or ultrasonic treatment) in a solvent (such as water) to easily obtain a uniformly dispersed monolayer structure.

[0105] Comparative Example 1

[0106] 8 g of β-cyclodextrin was dissolved in 100 ml of water and stirred at 80°C for 12 hours. Citric acid and sodium dihydrogen phosphate were added and mixed (sodium dihydrogen phosphate was one-tenth of the molar amount of citric acid, and the molar ratio of citric acid to β-cyclodextrin was 2:1). A uniform system was obtained by stirring. After reacting at 140°C for 4 hours, the obtained solid was centrifuged and washed with water several times. After heating and drying, a cyclodextrin polymer powder was obtained, which exhibited a three-dimensional disordered cross-linked structure and did not have a two-dimensional structure.

[0107] Comparative Example 2

[0108] 1 g of n-octyltrimethylammonium bromide was dissolved in 100 ml of water, and 8 g of β-cyclodextrin was dissolved in 100 ml of water. The mixture was then mixed and stirred at 80°C for 12 hours. After stopping stirring, the mixture was allowed to stand at 25°C for 24 hours. No self-assembled crystals were produced.

[0109] Comparative Example 3

[0110] First, dissolve 1 gram of sodium dodecyl sulfate in 100 milliliters of water, and dissolve 8 grams of β-cyclodextrin in 100 milliliters of water. Then mix the two together, and immediately add terephthalic acid and sodium dihydrogen phosphate (sodium dihydrogen phosphate is one-tenth of the molar amount of terephthalic acid, and the molar ratio of terephthalic acid to β-cyclodextrin is 2:1). After reacting at 140°C for 4 hours, the resulting solid product is a cyclodextrin polymer with a three-dimensional cross-linked structure.

[0111] Comparative Example 4

[0112] First, 3 grams of hexadecyltrimethylammonium bromide was dissolved in 100 milliliters of water, and 8 grams of β-cyclodextrin was dissolved in 100 milliliters of water. The two were then mixed and stirred at 80°C for 12 hours. After stopping stirring, the mixture was allowed to stand at 25°C for 24 hours. No self-assembled crystals were produced in the mixture.

[0113] Comparison of Comparative Examples 1, 2, and 4 reveals that, in the absence of a surfactant, when the surfactant's hydrophobic chain is short, or when the surfactant's ratio relative to the cyclodextrin is too high, the cyclodextrin molecules struggle to form ordered two-dimensional lamellae in solution, making it difficult to prepare a two-dimensional layered material via cross-linking. Comparative Example 3 demonstrates that the lack of sufficient stirring and stabilization can make it difficult to induce the formation of a self-assembled crystalline structure, thus preventing the formation of a two-dimensional layered material.

[0114] The present invention has been described in detail above with reference to the embodiments. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the spirit of the present invention.

Claims

1. A method for preparing a two-dimensional cyclodextrin polymer material, characterized in that: The steps include: The self-assembly agent and cyclodextrin molecules are stirred in a solvent to obtain a fully uniform mixing effect, and then allowed to stand until the system self-assembles to form a dispersion having a plate-like structure crystal; Mixing the dispersion with a cross-linking agent, reacting, solid-liquid separation, washing, and drying to obtain the two-dimensional cyclodextrin polymer material; The self-assembly agent includes a surfactant having a C10-C30 hydrophobic chain, and the molar ratio of the surfactant to the cyclodextrin molecule is 1:0.95-12.

2. The preparation method according to claim 1, characterized in that The cross-linking agent is selected from one or more of acyl chloride compounds, acid anhydride compounds, isocyanate compounds, halogenated alkane compounds, halogenated silane compounds, epoxysilane compounds, aminosilane compounds, halogenated epoxy compounds, aldehyde compounds, ester compounds, glycidyl ether compounds, halogenated triazine compounds, nitrile compounds, organic acids or salts thereof, organic bases or salts thereof, unsaturated hydrocarbon compounds, polyhydroxy polymers, polycarbonates, fluorinated polyolefins and acrylic acid-modified polymers, and the cross-linking agent has multiple functional groups that can react with the cyclodextrin molecules; And / or, the molar ratio of the cross-linking agent to the cyclodextrin molecules is 2-50:

1.

3. The preparation method according to claim 1, characterized in that The self-assembly agent includes a surfactant having a C10-C20 hydrophobic chain.

4. The preparation method according to claim 1, characterized in that The solvent is selected from at least one of water, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, isopropyl alcohol, chloroform, tetrahydrofuran, and trifluoroacetic acid; and / or, the amount of the surfactant added relative to the solvent is 1-600 mg / mL; And / or, the amount of the cyclodextrin molecules added to the solvent is 1-2000 mg / mL.

5. The preparation method according to claim 1, characterized in that The stirring temperature is 20-100°C, and the standing temperature is lower than the stirring temperature; And / or, the method further comprises the step of adding a catalyst and mixing before the reaction.

6. The preparation method according to claim 1, characterized in that The solid-liquid separation is carried out by centrifugation, vacuum filtration, screen filtration, gauze filtration or natural sedimentation; And / or, the drying is carried out by any one of heating drying, natural air drying, spray drying, vacuum drying, freeze drying or supercritical drying.

7. A two-dimensional cyclodextrin polymer material, characterized in that The layered structure is a planar structure formed by cyclodextrin molecules connected by covalent bonds. The thickness of the layered structure is 0.7-1 nm, and the sheet diameter is 10 nm-100 μm.

8. The two-dimensional cyclodextrin polymer material according to claim 7, characterized in that The two-dimensional cyclodextrin polymer material meets the following conditions: The layered structure comprises a pore structure, which includes one or more of micropores, mesopores and macropores, wherein the pore diameter of the micropores is less than 2 nm, the pore diameter of the mesopores is 2-50 nm, and the pore diameter of the macropores is greater than 50 nm.

9. The two-dimensional cyclodextrin polymer material according to claim 8, characterized in that The pore diameter of the micropores is greater than 0.5 nm and less than 2 nm, and the pore diameter of the macropores is 50-500 nm.

10. Use of the two-dimensional cyclodextrin polymer material obtained by the preparation method according to any one of claims 1 to 6, or the two-dimensional cyclodextrin polymer material according to any one of claims 7 to 9 in the fields of catalysts, functional block materials, drug delivery, gene transport, substance separation or purification, and pollutant adsorption or removal.

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