Multi-element composite MOFs membrane as well as preparation method and application thereof

Abstract

The invention provides a multi-element composite MOFs (Metal-Organic Frameworks) membrane as well as a preparation method and application thereof, and belongs to the field of MOF new material forming. The method comprises the following steps: firstly, preparing a binding material, wherein the binding material comprises organic silicon oligomer with functional groups of epoxy, hydroxyl, isocyanate, amido, sulfydryl, vinyl or siloxane and liquid polyisoprene or liquid polybutadiene containing epoxy, hydroxyl and amido; mixing a binding material, MOFs, a curing agent, a catalyst, a defoaming agent and a compatibilizer to obtain MOFs slurry; and finally, coating the MOFs slurry on a substrate, and curing to obtain the multi-element composite MOFs membrane. The multi-element composite MOFs membrane can be directly applied to treatment of all-component nuclear wastewater, shows a good adsorption effect under the conditions of multi-element competitive adsorption and mutual influence, and has the removal rate of more than 95% for Sr, Co, U, Th, Ag, Cs and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of MOF new material forming, and particularly relates to a multi-element composite MOF film and a preparation method and application thereof. BACKGROUND

[0002] MOF (Metal-Organic Frameworks) is a kind of super-porous nanomaterial, which is considered as a decisive material in the 21st century. The surface area of 1 gram of MOF is larger than a football field, and it is very suitable for detecting and capturing / adsorbing substances with small concentration, and has excellent performance in adsorption. MOF powder lacks flexibility and processability, and is therefore often compounded with polymers to form a MOF mixed matrix membrane. CN202410462390.8 discloses a metal-organic framework thin film composite membrane, a preparation method and application. After BPEI polymer is dissolved, a water phase monomer solution is obtained, and MOF nanomaterial is added. Then, PES membrane is soaked or coated to form a MOF water phase monomer layer, and a membrane with the MOF water phase monomer layer is obtained after drying. Then, the MOF composite membrane is obtained by soaking or coating with TMC n-hexane solution and drying. CN202410301369.X discloses a solid electrolyte composite membrane, a preparation method and application thereof. PAN and PVDF-HFP with three-dimensional porous structure are used as a substrate, and MOF material is loaded on the substrate by electrospinning to prepare PAN@MOF membrane and PVDF-HFP@MOF membrane.

[0003] There are only weak physical interactions between MOFs and polymer matrix, which limits the further industrial application. Chemical cross-linking between MOFs and polymer matrix can greatly improve this problem [J. Mater. Chem. A. 2015. 3(9): 5014; Energy Environ. Sci., 2018, 11(3): 544. Chem. Mater., 2016, 28(10): 3318]. Cohen et al. [J. Am. Chem. Soc. 2020, 142(24): 10863] proposed to use organic polymers as connecting ligands of MOFs, and constructed one-dimensional amorphous polymers into three-dimensional porous hybrid materials, to prepare polymer hybrid MOF materials, thereby dispersing MOFs in polymers at the molecular level, with the advantages of porous MOFs crystals and high stability polymers. Li et al. [J. Am. Chem. Soc., 2020, 142(43): 18503.] also enhanced the interfacial compatibility between the inner MOF and the outer polymer by constructing a thin-shell MOF intermediate layer structure, thereby improving the separation selectivity of the mixture matrix membrane for ethylene / ethane by 76%. Zhu et al. [ACS Appl. Mater Interfaces, 2014, 6(8): 5609] enhanced the interfacial bonding force between MOFs and polyimide matrix by the bonding effect of carboxyl on MOFs and amino on polymers. Zhu et al. [ACS Appl. Mater Interfaces, 2016, 8(46): 32041] also wrapped HKUST-1 with ionic liquids to enhance the interfacial compatibility between MOFs and polymer matrix, limit the generation of interfacial voids, and enhance the selective separation ability of the membrane for CO2. Knebel et al. [Nat. Mater., 2020, 19(12): 1346] modified the outer surface of MOFs to enable them to be uniformly dispersed in solution for a long time, forming a continuous, stable, and processable porous MOFs liquid, and on this basis, they prepared a MOFs hybrid matrix membrane with extremely high dispersity: they modified the outer surface of ZIF-67 with N-heterocyclic carbene ligands, enabling 250 mm ZIF-67 to be stably dispersed in solution, giving the dispersion excellent processability. This dispersion can be co-processed with a polymer matrix to produce a hybrid matrix membrane with a loading capacity of up to 47.5 wt%, and this membrane exhibits excellent mechanical stability: the separation ability for propylene and ethylene is 2.5 times higher than that of a hybrid matrix membrane prepared from ZIF-67 modified with N-heterocyclic carbene ligands. Long-chain organic compounds can also be used to modify the surface of MOFs to achieve uniform dispersion in the matrix.Queen et al. [ACS Appl. Mater. Interfaces, 2016, 8(16): 10098] used oleic acid molecules to modify the hydrophilic UiO-66-NH2 by ligand exchange method, and the modified MOFs showed good dispersibility in hydrophobic solvents, which was beneficial to the preparation of high-dispersity MOF mixed matrix membranes.

[0004] Wang et al. [Angew. Chem. Int. Ed., 2015, 54(14): 4259] used photo-induced post-synthetic polymerization to covalently link flexible long chains on MOFs crystals, which could carry out mild and fast polymerization reaction, and the flexible polymer chains formed ordered structure, which endowed MOFs with high elasticity and easy processability. The UiO-66-NH2 was first modified by methacrylamide functional groups, and then copolymerization with butyl methacrylate monomers under ultraviolet irradiation. The compatibility between the functionalized MOFs and the polymer matrix was greatly improved, and the MOFs loading was as high as 60%. The introduction of polymers greatly affected the surface area and pore properties of MOFs, and the preparation of high-performance MOF membranes still faced great challenges. On the other hand, the preparation of high-solid-content MOF membranes while maintaining the toughness of the membranes was one of the trends of future MOF applications. SUMMARY

[0005] The application provides a kind of multi-element composite MOFs membrane and its preparation method and application, the multi-element composite MOFs membrane of the application can be directly applied to the treatment of full component nuclear waste water.

[0006] In order to achieve the above purpose, the technical scheme adopted by the application is as follows:

[0007] The application first provides a preparation method of a multi-element composite MOFs membrane, comprising:

[0008] Step one: preparing a bonding material, the bonding material comprises organosilicon oligomers with functional groups of epoxy, hydroxyl, isocyanate, amine group, mercapto, vinyl or siloxane, and liquid polyisoprene or liquid polybutadiene containing epoxy, hydroxyl and amine groups;

[0009] Step two: mixing the bonding material of step one, MOFs, curing agent, catalyst, defoaming agent and compatibilizer to obtain MOFs slurry;

[0010] Step three: coating the MOFs slurry of step two on a substrate to cure and obtain a multi-element composite MOFs membrane.

[0011] Preferably, the molecular weight of the organosilicon oligomers in step one is 200-2000, and the content of functional groups is 0.2-0.8 mmol / g.

[0012] Preferably, the liquid polyisoprene or liquid polybutadiene in step one has a molecular weight of 200-2000, a functional group content of 0.08-0.8 mmol / g, a 1,4-content of ≥96% for liquid polyisoprene, and a 1,4-content of ≥92% for liquid polybutadiene.

[0013] Preferably, the MOFs are ZIF-8, MIL-101 (Al, Fe, Cr), UIO-66 or ZIF-67, and the number of MOF types is ≥5.

[0014] Preferably, in the slurry in step two, the solid content of the MOFs is 20-80%, the content of the curing agent is 2-20%, the content of the catalyst is 20-200 ppm, the content of the defoaming agent is 1-160 ppm, and the content of the solubilizing agent is 0.1-3%.

[0015] Preferably, the curing agent is an aliphatic amine, a polyisocyanate or a high-hydrogen silicone oil, and the catalyst is an organotin or platinum;

[0016] The defoaming agent is an organosilicon and a polyether-modified polysiloxane;

[0017] The solubilizing agent is one or more of polyethylene glycol, lecithin, propylene glycol, polyvinylpyrrolidone and hydroxypropyl methyl cellulose.

[0018] Preferably, the curing temperature in step three is 30-60°C, and the curing time is 5s-60s.

[0019] The application also provides a multi-component composite MOFs film prepared by the above method.

[0020] Preferably, the multi-component composite MOFs film has a thickness of 50-200 microns, and a size of ≥200×5000.

[0021] The application also provides the use of the above multi-component composite MOFs film in nuclear waste water treatment.

[0022] Advantages of the application

[0023] This invention provides a multi-component composite MOF membrane, its preparation method, and its applications. The invention uses organosilicon oligomers containing functional groups such as epoxy, hydroxyl, isocyanate, amino, mercapto, vinyl, and siloxane, and liquid polyisoprene or liquid polybutadiene containing epoxy, hydroxyl, and amino groups as binders. MOF materials with selective adsorption for different nuclides are screened and dispersed in the oligomers. The proportions and composition of the oligomers, curing agents, catalysts, defoamers, compatibilizers, and MOF preparation agents are controlled to prepare a polymer-based multi-component composite MOF slurry. The curing process is controlled, and the MOF membrane is prepared by low-temperature spraying or spin coating, controlling the oligomer composition and regulating the bonding strength between the MOF and the polymer. Simultaneously, the influence of the polymer on the MOF surface area and pore characteristics is reduced. This multi-component composite MOF membrane can be directly applied to the treatment of all components of nuclear wastewater, exhibiting excellent adsorption effects under conditions of multi-element competitive adsorption and mutual influence, with removal rates exceeding 95% for Sr, Co, U, Th, Ag, and Cs. Attached Figure Description

[0024] Figure 1 The NMR spectrum of the epoxy-containing liquid polyisoprene prepared in Example 1;

[0025] Figure 2 The NMR spectrum of hydroxyl-containing liquid polybutadiene prepared in Example 2;

[0026] Figure 3 The NMR spectrum of the vinyl organosilicon oligomer prepared in Example 4 is shown. Detailed Implementation

[0027] This invention first provides a method for preparing a multi-component composite MOF membrane, comprising:

[0028] Step 1: Prepare the bonding material, which includes organosilicon oligomers with functional groups of epoxy, hydroxyl, isocyanate, amino, mercapto, vinyl or siloxane and liquid polyisoprene or liquid polybutadiene containing epoxy, hydroxyl or amino groups.

[0029] Step 2: Mix the adhesive material, MOFs, curing agent, catalyst, defoamer and compatibilizer from Step 1 to obtain MOFs slurry;

[0030] Step 3: Coat the MOFs slurry from Step 2 onto the substrate and cure it to obtain a multi-component composite MOFs membrane.

[0031] According to the present application, the adhesive material can form a network structure by reacting with a curing agent under heating conditions, the silicone oligomer is methyl silicone oil, the functional groups (epoxy, hydroxyl, isocyanate, amine, mercapto, vinyl, silicon hydrogen or siloxane) are at the end and side chain of the molecular chain, the molecular weight is 200-2000, the content of the functional groups is 0.2-0.8 mmol / g, preferably the molecular weight is 200-1800; preferably the content of the functional groups is 0.23-0.76 mmol / g; more preferably the molecular weight is 220-1680; preferably the content of the functional groups is 0.26-0.60 mmol / g.

[0032] According to the present application, the preparation method of the silicone oligomer with the functional groups of epoxy groups preferably comprises:

[0033] The allyl epoxy polyether or allyl glycidyl ether is reacted with hydrogen-containing silicone oil by addition reaction to obtain an epoxy group-containing silicone oligomer, the reaction temperature is 25-55°C, the reaction time is 30-90 minutes, preferably the reaction is carried out at 25-50°C for 30-80 minutes, more preferably the reaction is carried out at 25-45°C for 35-70 minutes; the molar ratio of the carbon-carbon double bond in the allyl epoxy polyether or allyl glycidyl ether to the silicon hydrogen bond in the hydrogen-containing silicone oil is (0.8-1.4):1.

[0034] According to the present application, the preparation method of the silicone oligomer with the functional groups of hydroxyl groups preferably comprises:

[0035] Diethanolamine is added to the above-mentioned epoxy group-containing silicone oligomer, and stirring reaction is carried out at 45-65°C for 1-4 hours to obtain a hydroxyl group-containing silicone oligomer, the reaction conditions are preferably stirring reaction at 50-65°C for 1-3.5 hours, more preferably stirring reaction at 55-65°C for 1.5-3.5 hours; the molar ratio of the diethanolamine to the epoxy groups is preferably (0.8-1.4):1.

[0036] According to the present application, the preparation method of the silicone oligomer with the functional groups of amine groups preferably comprises:

[0037] The amino compound containing carbon-carbon double bond is preferably one or more of olefin-polyethylene glycol-amino, 6-amino hexenoic acid, 1-amino-10-undecene or 2-propylene amine, more preferably olefin-polyethylene glycol-amino or 1-amino-10-undecene; the reaction temperature is preferably 25-55°C, more preferably 25-50°C, the reaction time is 30-90 minutes, more preferably 30-80 minutes, most preferably 25-45°C for 35-70 minutes; the molar ratio of the carbon-carbon double bond in the amino compound containing carbon-carbon double bond to the silicon-hydrogen bond in the hydrogen-containing silicone oil is preferably (0.8-1.4):1;

[0038] According to the present application, the preparation method of the silicone oligomer with the functional group of isocyanate preferably comprises:

[0039] The isocyanate group-containing silicone oligomer is prepared by polymerization of isocyanate group-containing propyl methyl dimethoxy silane and octamethyl cyclotetrasiloxane (D4 monomer), using alkali metal as catalyst, preferably K and Na, the reaction temperature is 110-165°C, the reaction time is 60-180 minutes, the reaction condition is preferably 110-150°C for 70-150 minutes, more preferably 120-145°C for 90-150 minutes; the molar ratio of isocyanate group-containing propyl methyl dimethoxy silane to D4 monomer is preferably 1:(10-30), and the catalyst is preferably added in an amount of 0.1-0.8%;

[0040] According to the present application, the preparation method of the silicone oligomer with the functional group of vinyl preferably comprises:

[0041] The vinyl-containing silicone oligomer is prepared by polymerization of methyl vinyl diethoxy silane, methyl vinyl cyclotrisiloxane and D4 monomer, using alkali metal as catalyst, the reaction temperature is 110-165°C, the reaction time is 60-180 minutes, the reaction condition is preferably 110-150°C for 70-150 minutes, more preferably 120-145°C for 90-150 minutes; the molar ratio of methyl vinyl diethoxy silane, methyl vinyl cyclotrisiloxane and D4 monomer is preferably 1:(0.5-5):(10-30); and the catalyst is preferably added in an amount of 0.1-0.8%;

[0042] According to the present application, the preparation method of the silicone oligomer with the functional group of active siloxane preferably comprises:

[0043] The active siloxane-containing silicone oligomer is obtained by polymerization of methyl triethoxysilane and D4 monomer, using alkali metal as catalyst, reaction temperature is 110-165°C, reaction time is 60-180 minutes, reaction conditions are preferably 110-150°C for 70-150 minutes, more preferably 120-145°C for 90-150 minutes. The molar ratio of methyl triethoxysilane and D4 monomer is preferably 1:(10-30); the catalyst is added in an amount of 0.1-0.8%.

[0044] According to the present application, the liquid polyisoprene or polybutadiene containing epoxy, hydroxyl or amine groups has a molecular weight of 200-2000, preferably a molecular weight of 200-1800, more preferably 230-1680; the functional group content is 0.08-0.8 mmol / g, preferably the content of functional groups is 0.10-0.76 mmol / g, more preferably 0.12-0.72 mmol / g; wherein the 1,4-content of the liquid polyisoprene is ≥96%, preferably >96%, more preferably ≥96.5%; the 1,4-content of the liquid polybutadiene is ≥92%, preferably >93%, more preferably >94%.

[0045] According to the present application, the preparation method of the liquid polyisoprene or polybutadiene containing epoxy, hydroxyl or amine groups can be prepared by conventional methods in the art without special restrictions. The present application uses a double lithium initiator to introduce carbon-carbon double bonds at the chain end or side end by stepwise polymerization. Hexane is used as the solvent, and isoprene monomer or butadiene monomer and comonomer are added. After the monomers are completely reacted, isoprene monomer or butadiene monomer and comonomer are added again, and the process is repeated in turn. The structure of the double lithium initiator is preferably:

[0046] The comonomer is one or two of 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 3,7-dimethyl-1,6-octadiene or 7-methyl-1,6-octadiene, preferably one or two of 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 7-methyl-1,6-octadiene, more preferably one or two of 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene; the total content of the comonomer is controlled to be 0.2-6.5% of isoprene, preferably 0.26-5.65%, more preferably 0.28-5.63%; the reaction temperature is controlled to be 20-50°C, and the reaction time is 50-200 minutes, preferably 25-50°C for 50-180 minutes, more preferably 30-50°C for 60-180 minutes. All monomers and solvents are distilled after stirring overnight with CaH2 before use, and are placed in airtight containers and protected by nitrogen.

[0047] The preparation method of the liquid polyisoprene containing epoxy groups comprises:

[0048] The liquid polyisoprene containing epoxy group is added into excess amine compound, and the reaction is carried out at a temperature of 50-130°C for 20-120 minutes to obtain liquid polyisoprene with amine group at the end, wherein the amine compound is preferably ethylenediamine, p-phenylenediamine or m-phenylenediamine, and more preferably ethylenediamine; the reaction conditions are preferably 50-120°C for 20-100 minutes, and more preferably 60-110°C for 30-90 minutes; and the molar ratio of the epoxy group in the liquid polyisoprene containing epoxy group to the amine compound is preferably (1.2-1.8):1.

[0049] The method for preparing the liquid polyisoprene containing amine group comprises the following steps:

[0050] The liquid polyisoprene containing epoxy group is added into excess amine compound, and the reaction is carried out at a temperature of 50-130°C for 20-120 minutes to obtain liquid polyisoprene with amine group at the end, wherein the amine compound is preferably ethylenediamine, p-phenylenediamine or m-phenylenediamine, and more preferably ethylenediamine; the reaction conditions are preferably 50-120°C for 20-100 minutes, and more preferably 60-110°C for 30-90 minutes; and the molar ratio of the epoxy group in the liquid polyisoprene containing epoxy group to the amine compound is preferably (1.2-1.8):1.

[0051] The method for preparing the liquid polyisoprene containing hydroxyl group comprises the following steps:

[0052] The diethanolamine is added into the liquid polyisoprene containing epoxy group, and the reaction is carried out at a temperature of 45-65°C for 1-4 hours to obtain liquid polyisoprene containing hydroxyl group, wherein the reaction conditions are preferably 45-60°C for 1-3 hours, and more preferably 50-60°C for 2-3 hours; and the molar ratio of the diethanolamine to the epoxy group in the liquid polyisoprene containing epoxy group is (0.8-1.4):1.

[0053] The liquid polybutadiene containing epoxy group, hydroxyl group and amine group is prepared according to the above method.

[0054] According to the present application, the multi-element composite MOFs slurry is prepared from a binding material, a curing agent, a catalyst, a defoaming agent, a solubilizing agent, and different kinds of MOFs. In the slurry, the solid content of the MOFs is 20-80%, preferably 25-80%, and more preferably 30-76%; the number of kinds of MOFs is ≥5, preferably ≥6; the content of the curing agent is 2-20%, preferably 2.2-18.6%, and more preferably 2.5-18%; the content of the catalyst is 20-200 ppm, preferably 25-180 ppm, and more preferably 28-168 ppm; the content of the defoaming agent is 1-160 ppm, preferably 1.5-155 ppm, and more preferably 1.8-150 ppm; and the content of the solubilizing agent is 0.1-5%, preferably 0.12-2.8%, and more preferably 0.16-2.6%.

[0055] The curing agent is a commercial product of aliphatic amines, polyisocyanate, high-hydrogen silicone oil, etc., preferably 2-methylpentanediamine, ethylenediamine, hexanediamine, PMDI or TDI; the catalyst is a commercial product of organic tin or platinum, preferably dibutyltin dilaurate; the MOFs are preferably ZIF-8, MIL-101 (Al, Fe, Cr), UIO-66 or ZIF-67, with a particle size of 200-800 mesh, preferably 220-780 mesh, and more preferably 320-760 mesh; the defoaming agent is a silicone-based and polyether-modified polysiloxane-based product, preferably product model DY-ET100 or DY-ET200, with a PH of 6.5-8 and a molecular weight of 130-560, preferably a PH of 7-8 and more preferably a PH of 7.5-8, and preferably a molecular weight of 140-550 and more preferably a molecular weight of 156-536; and the solubilizing agent is one or more of polyethylene glycol, lecithin, propylene glycol, polyvinylpyrrolidone, hydroxypropyl methyl cellulose, etc., preferably one or more of polyethylene glycol, lecithin, propylene glycol, polyvinylpyrrolidone, hydroxypropyl methyl cellulose, and more preferably one of polyethylene glycol, lecithin, propylene glycol, polyvinylpyrrolidone, hydroxypropyl methyl cellulose.

[0056] According to the application, the MOFs slurry is prepared, the MOF material selectively adsorbed to different nuclides is screened, one or more of the organosilicon oligomers with functional groups of epoxy, hydroxyl, isocyanate, amine group, mercapto, vinyl or siloxane and one or more of the liquid polyisoprene or liquid polybutadiene containing epoxy, hydroxyl, amine group are mixed to obtain the mixed adhesive material, the mass ratio of the organosilicon oligomer and the liquid polyisoprene or liquid polybutadiene is preferably (1-2):(1-1.5); the plurality of MOFs is dispersed in the adhesive material by stirring and ultrasonic homogenization under the condition of room temperature and nitrogen protection, the temperature of the slurry system is controlled to be not more than 30℃, the water content is ≤30ppm, the stirring time is ≤30 minutes, preferably the temperature of the slurry system is controlled to be not more than 28℃, the water content is ≤26ppm, the stirring time is ≤25 minutes, more preferably the temperature of the slurry system is controlled to be not more than 26℃, the water content is ≤24ppm, the stirring time is ≤20 minutes; the composition, ratio and viscosity of the oligomer are regulated to prepare the polymer-based multi-element composite MOFs slurry, and the viscosity of the slurry is 0.2-20 Pa.S (room temperature), preferably 0.3-16 Pa.S (room temperature), more preferably 0.3-13 Pa.S (room temperature).

[0057] The multi-element composite MOFs film is prepared by controlling the functional groups, composition ratio and curing agent of the oligomer, controlling the curing process, preparing the MOF film by low-temperature spraying or spin coating, and regulating the bonding strength between the MOF and the polymer.

[0058] According to the application, the curing process is that the curing temperature is 30-60℃, the curing time is 5s-60s, the curing temperature and time are preferably 35-56℃ and 5s-55s, more preferably 35-50℃ and 5s-50s; the MOF slurry is sprayed or spin coated on the substrate under the condition of 30-60℃, preferably 32-55℃, more preferably 35-55℃; and the MOF film is prepared by peeling off from the substrate after standing for 30-300 minutes, preferably 35-260 minutes, more preferably 40-230 minutes, and the thickness of the film is controlled to be 50-200 microns, preferably 50-180 microns, more preferably 60-160 microns, and the size of the film is ≥200×5000.

[0059] The prepared MOF film is used for nuclear waste water treatment, specifically the MOF film is placed in the waste water containing Sr, Co, U, Th, Ag, Cs and the like, and the nuclear elements are removed by adsorption.

[0060] The application will be further described in detail below with specific examples, and the raw materials involved in the examples are commercially available.

[0061] Example 1

[0062] (1) Synthesis and structure control of thermally curable oligomer-based adhesive materials

[0063] The epoxy group-containing liquid polyisoprene was prepared by using allyl glycidyl ether and hydrogen-containing silicone oil through addition reaction. The ratio of the two was 1:1 in terms of the molar amount of carbon-carbon double bond and silicon-hydrogen bond, and the reaction was carried out at 45°C for 50 minutes. The molecular weight was 860, and the content of functional groups was 0.36 mmol / g.

[0064] The epoxy group-containing liquid polyisoprene was prepared by using allyl glycidyl ether and hydrogen-containing silicone oil through addition reaction. The ratio of the two was 1:1 in terms of the molar amount of carbon-carbon double bond and silicon-hydrogen bond, and the reaction was carried out at 45°C for 50 minutes. The molecular weight was 860, and the content of functional groups was 0.36 mmol / g. The same as above, hexane was used as the solvent, isoprene monomer and comonomer 3,7-dimethyl-1,6-octadiene were added in batches, the reaction temperature was controlled at 30°C, after the monomers were completely reacted, isoprene monomer and comonomer were added again, and the process was repeated 3 times. The mass ratio of the three times of added materials was 1:1:1. The total content of comonomer in the feeding ratio was 0.8% of isoprene, the molar ratio of lithium initiator and monomer was accurately calculated, the molecular weight of liquid isoprene was controlled at 1300, and the total reaction time was 180 minutes. After removing the solvent, the obtained product was added into formic acid and hydrogen peroxide, the molar ratio of double bond:formic acid:H2O2 was controlled at 10:1:1, the reaction temperature was slowly increased to 40°C, and the reaction time was 3.5 hours, to obtain the liquid polyisoprene containing epoxy groups, with a functional group content of 0.56 mmol / g and a 1,4-content of 96.3%. Figure 1 NMR spectrum of the epoxy group-containing liquid polyisoprene prepared in Example 1;

[0065] (2) Preparation of multi-component composite MOFs slurry based on thermally curable adhesive materials

[0066] The epoxy group-containing liquid polyisoprene prepared in Example 1 was mixed with the epoxy group-containing liquid polyisoprene prepared in Example 1 at a mass ratio of 1:1, and then 800-mesh ZIF-8, MIL-101(Al), MIL-101(Fe), MIL-101(Cr), UIO-66, KAUST-7, polyvinylpyrrolidone, and polyether-modified polysiloxane(DY-ET100) were added. The MOFs solid content was controlled at 50%, and the mass ratio of ZIF-8, MIL-101(Al), MIL-101(Fe), MIL-101(Cr), UIO-66, and KAUST-7 was 2:1:1:1.5:1:1. After stirring and homogenizing under nitrogen protection, the slurry system temperature was controlled at not more than 30°C, and the water content was ≤30 ppm. Multi-isocyanate curing agent(TDI), catalyst dibutyltin dilaurate, defoaming agent, and solubilizer were added. The content of the curing agent was 5%, the content of the catalyst was 30 ppm, the content of the defoaming agent was 8 ppm, and the content of the solubilizer was 0.6%. After stirring for 26 minutes, the slurry viscosity was 5 Pa.S(room temperature);

[0067] (3) Curing process and preparation of multi-component MOFs membrane material

[0068] The slurry was spin-coated on a glass or Teflon plate substrate, the film thickness was controlled to be 100-130 microns, cured at 50°C for 60 seconds, and then left to stand for 180 minutes to prepare a film with a size of 200 x 5000.

[0069] (4) Nuclear waste water treatment application

[0070] The prepared MOFs membrane was used for nuclear waste water treatment, specifically, the MOFs membrane was placed in waste water containing Sr, Co, U, Th, Ag, Cs, etc. for 7 hours, the total ion concentration was about 180 mg / L, and the adsorption removal rate was 90%.

[0071] Example 2

[0072] (1) Synthesis and structure control of thermally cured oligomer-based adhesive material

[0073] An epoxy silicone oligomer was obtained by addition reaction of allyl glycidyl ether and hydrogen-containing silicone oil, the molar ratio of the two was 1.2:1, and the reaction was carried out at 45°C for 50 minutes. Diethanolamine was added to the epoxy silicone oligomer, and the molar ratio of diethanolamine to epoxy groups was controlled to be 1.2:1, and the reaction was carried out at 65°C for 4 hours to obtain a hydroxyl silicone oligomer, the molecular weight was controlled to be 1550, and the content of functional groups was 0.68 mmol / g.

[0074] A double lithium initiator was used, hexane was used as the solvent, and isoprene monomer and comonomer 1,7-octadiene were added in two portions. After the first portion of monomer was completely reacted, the second portion of isoprene monomer and comonomer was added, and the mass ratio of the two portions of material was 1:1. The total content of comonomer was controlled to be 0.8% of isoprene; the reaction temperature was controlled to be 40°C, and the reaction time was 60 minutes to obtain a product with a molecular weight of 1520. Benzoic acid peroxide was slowly added to the liquid polyisoprene prepared above, the molar ratio of double bonds to benzoic acid peroxide was controlled to be 10:1.3, the reaction temperature was slowly increased to 40°C, and the reaction time was 4 hours to obtain a liquid polymer containing epoxy groups. Diethanolamine was added to the liquid polymer containing epoxy groups, the molar ratio of diethanolamine to epoxy groups was controlled to be 1.2:1, and the reaction was carried out at 50°C for 3.5 hours to obtain a liquid polyisoprene containing hydroxyl groups, the functional group content was 0.56 mmol / g. The nuclear magnetic resonance spectrum is shown in Figure 2 .

[0075] (2) Preparation of multi-component MOFs slurry based on thermally cured adhesive material

[0076] The silicone oligomer and liquid polyisoprene are mixed in a mass ratio of 2:1, a defoaming agent, a compatibilizer and MOFs are added, wherein the MOFs are ZIF-8, MIL-101(Al), MIL-101(Cr), UIO-66 and KAUST-7, the mass ratio is 1:1:1:2:1.5, the particle size is 600 mesh, the defoaming agent is polyether modified polysiloxane(DY-ET100), the solubilizer is polyethylene glycol, the solid content of the MOFs is 70%, the content of the defoaming agent is 20 ppm, the content of the solubilizer is 1.6%, the plurality of MOFs is dispersed in the oligomer by stirring and ultrasonic homogenization under the condition of room temperature and nitrogen protection, the temperature of the slurry system is controlled to be not more than 30°C, the water content is ≤30 ppm, the stirring time is 20 minutes, the polymer-based multi-component composite MOFs slurry is prepared, and the viscosity of the slurry is 10 Pa.S(room temperature). Then, a curing agent hexanediamine and a catalyst dibutyltin dilaurate are added, the content of the curing agent is 8%, and the content of the catalyst is 50 ppm.

[0077] (3) Curing process and preparation of multi-component composite MOFs film material

[0078] The slurry is spin-coated on a glass or a fluorotetra plate substrate, the film thickness is controlled to be 100-130 microns, the film is cured at 50°C for 60 seconds, and then is left to stand for 180 minutes, and a film with a size of 200x5000 is prepared.

[0079] (4) Nuclear waste water treatment application

[0080] The prepared MOFs film is used for nuclear waste water treatment, specifically, the MOFs film is placed in waste water containing Sr, Co, U, Th, Ag, Cs and the like for 7 hours, the total ion concentration is about 180 mg / L, and the adsorption removal rate is 90%.

[0081] Example 3

[0082] (1) Synthesis and structure regulation of thermosetting oligomer-based adhesive material

[0083] The amine-based silicone oligomer is obtained by addition reaction of olefin-polyethylene glycol-amino, 1-amino-10-undecene and hydrogen-containing silicone oil, the molar ratio of carbon-carbon double bond and silicon-hydrogen bond is 0.3:0.8:1, the reaction temperature is 35°C, and the reaction time is 40 minutes; the control molecular weight is 1130, and the content of functional groups is 0.36 mmol / g.

[0084] The double lithium initiator is used, hexane is used as the solvent, and the butadiene monomer and the comonomer 7-methyl-1, 6-octadiene are added in three times. After the first portion of the monomer is completely reacted, the second portion and the third portion of the butadiene monomer and the comonomer are sequentially added. The mass ratio of the three times of added materials is 1:1:1. The total content of the comonomer is controlled to be 4.5% of the butadiene. The reaction temperature is controlled to be 40°C, and the reaction time is 180 minutes. A liquid polybutadiene with a molecular weight of 1200 and a 1, 4-content of ≥92% is obtained. The benzenecarb- oxy peroxide is slowly added dropwise into the liquid polybutadiene prepared in the above preparation. The molar ratio of the double bond to the benzenecarb-oxy peroxide is 10:1.2. The reaction temperature is slowly increased to 40°C. The reaction time is 4 hours. A liquid polymer containing an epoxy group is obtained. The functional group content is 0.66 mmol / g.

[0085] (2) Preparation of a multi-component composite MOFs slurry based on a thermally curable adhesive material

[0086] The silicone oligomer and the liquid polybutadiene are mixed in a mass ratio of 1:1.5. A defoaming agent, a compatibilizer, and MOFs are added. The MOFs are ZIF-8, MIL-101(Al), MIL-101(Fe), MIL-101(Cr), UIO-66, and KAUST-7. The mass ratio of the MOFs is 1:1:1:1:1:1. The particle size is 600 mesh. The defoaming agent is a polyether-modified polysiloxane (DY-ET100). The solubilizing agent is polyethylene glycol. The solid content of the MOFs is 70%. The content of the defoaming agent is 80 ppm. The content of the solubilizing agent is 2.6%. The multi-component MOFs are dispersed in the oligomer by stirring and ultrasonic homogenization under the condition of room temperature and nitrogen protection. The temperature of the slurry system is controlled to be not more than 30°C. The water content is ≤30 ppm. The stirring time is 30 minutes. A polymer-based multi-component MOFs slurry is prepared. The viscosity of the slurry is 15 Pa.S (at room temperature). Then, a curing agent, polyisocyanate (PMDI), and a catalyst, dibutyltin dilaurate, are added. The content of the curing agent is 10%. The content of the catalyst is 25 ppm.

[0087] (3) Curing process and preparation of a multi-component composite MOFs film material

[0088] The slurry is sprayed on a glass or a fluorotetra plate substrate. The film thickness is controlled to be 100-130 microns. The film is cured at 60°C for 20 seconds. Then, the film is left to stand for 240 minutes. A film with a size of 200x5000 is prepared.

[0089] (4) Application of the film to the treatment of nuclear waste water

[0090] The MOFs film prepared in (3) is used for the treatment of nuclear waste water. Specifically, the MOFs film is placed in waste water containing Sr, Co, U, Th, Ag, Cs, and the like for 7 hours. The total ion concentration is about 180 mg / L. The adsorption removal rate is 88%.

[0091] Example 4

[0092] (1) Synthesis and structure control of thermally cured oligomer-based adhesive materials

[0093] Vinyl organosilicon oligomer was obtained by polymerization of methyl vinyl diethoxysilane, methyl vinyl cyclotrisiloxane and D4 monomer, the molar ratio of which was 1:1:15, using KOH as catalyst, the reaction temperature was 150°C, the reaction time was 180 minutes, the controlled molecular weight was 850, and the content of functional groups was 0.2 mmol / g. The nuclear magnetic resonance spectrum of the vinyl organosilicon oligomer is shown in Figure 3

[0094] The liquid polybutadiene was obtained by using double lithium initiator, hexane as solvent, adding butadiene monomer and comonomer 7-methyl-1,6-octadiene twice, after the first monomer was completely reacted, the second butadiene monomer and comonomer were added, the mass ratio of the two added materials was 1:1, the total content of comonomer was controlled to be 6.5% of butadiene; the reaction temperature was controlled to be 40°C, and the reaction time was 180 minutes, the molecular weight of the liquid polybutadiene was 1100, and the 1,4-content was ≥94%; peroxide benzoic acid was slowly added to the liquid polybutadiene prepared above, the molar ratio of double bond: peroxide benzoic acid was controlled to be 10:1.2, the reaction temperature was slowly increased to 40°C, and the reaction time was 4 hours, to obtain a liquid polymer containing epoxy groups; diethanolamine was added to the liquid polymer containing epoxy groups, the molar ratio of diethanolamine to epoxy groups was controlled to be 1.2:1, and the reaction was stirred at 50°C for 4 hours to obtain a liquid polybutadiene containing hydroxyl groups, the functional group content was 0.33 mmol / g.

[0095] (2) Preparation of multi-element composite MOFs slurry based on thermally cured adhesive materials

[0096] ​Mixing the oligomer and liquid polybutadiene in a mass ratio of 1:1, adding defoaming agent, compatibilizer, MOFs, wherein the MOFs are ZIF-8, MIL-101(Al), MIL-101(Fe), MIL-101(Cr), UIO-66, KAUST-7 and ZIF-67, with a mass ratio of 1:1:1:1:1:1:1, the particle size is 600 mesh, the defoaming agent is polyether modified polysiloxane (DY-ET100), the solubilizer is polyethylene glycol, the solid content of MOFs is 50%, the content of defoaming agent is 60 ppm, and the content of solubilizer is 2.2%, under the condition of room temperature and nitrogen protection, the multiple MOFs are dispersed in the oligomer by stirring and ultrasonic homogenization, the temperature of the slurry system is controlled to be not more than 30℃, the water content is ≤30 ppm, the stirring time is 30 minutes, the polymer-based multiple composite MOFs slurry is prepared, and the viscosity of the slurry is 8.0 Pa.S (at room temperature). Then, the curing agent high hydrogen-containing silicone oil and the catalyst dibutyltin dilaurate are added, the content of the curing agent is 20%, and the content of the catalyst is 35 ppm.

[0097] (3) Curing process and preparation of multiple composite MOFs film material

[0098] The slurry is sprayed on a glass or Teflon plate substrate, the film thickness is controlled to be 100-130 microns, the film is cured at 50℃ for 60 seconds, and then is placed for 300 minutes to prepare a film with a size of 200x5000.

[0099] (4) Application in nuclear waste water treatment

[0100] The prepared MOFs film is used in nuclear waste water treatment, specifically, the MOFs film is placed in waste water containing Sr, Co, U, Th, Ag, Cs and the like for 7 hours, the total ion concentration is about 180 mg / L, and the adsorption removal rate is 91%.

[0101] Example 5

[0102] (1) Synthesis and structure regulation of thermosetting oligomer-based adhesive material

[0103] An epoxy silicone oligomer is obtained by addition reaction of allyl glycidyl ether and hydrogen-containing silicone oil, the molar ratio of double bond carbon-carbon double bond to silicon hydrogen bond is controlled to be 1:1, the reaction is carried out at 45℃ for 50 minutes, diethanolamine is added to the epoxy silicone oligomer, the molar ratio of diethanolamine to epoxy group is controlled to be 1.2:1, and the reaction is carried out at 65℃ for 4 hours to obtain a hydroxyl silicone oligomer, the molecular weight is controlled to be 850, and the content of functional groups is 0.66 mmol / g.

[0104] The methyl triethoxysilane and D4 monomer are polymerized at a molar ratio of 1:28, NaOH is used as a catalyst, the amount of addition is 0.5%, the reaction temperature is 150°C, and the reaction time is 180 minutes, to obtain an organosilicon oligomer containing active siloxane, the molecular weight is 880, and the content of functional groups is 0.31 mmol / g.

[0105] The double lithium initiator is used, hexane is used as a solvent, isoprene monomer and comonomer 7-methyl-1, 6-octadiene are added twice, after the first monomer is completely reacted, the second isoprene monomer and comonomer are added, the mass ratio of the two times of added materials is 1:1, the total content of the comonomer is controlled to be 0.8% of isoprene; the reaction temperature is controlled at 40°C, and the reaction time is 60 minutes, to obtain a liquid polyisoprene with a molecular weight of 1440. Benzoic acid peroxide is slowly added dropwise into the liquid polyisoprene prepared above, the molar ratio of carbon-carbon double bond to benzoic acid peroxide is controlled to be 10:1.5, the reaction temperature is controlled to slowly rise to 40°C, and the reaction time is 4 hours, to obtain a liquid polymer containing epoxy groups. Diethanolamine is added to the liquid polymer containing epoxy groups, the molar ratio of diethanolamine to epoxy groups is controlled to be 1:1.2, and the stirring reaction is carried out at 50°C for 3.5 hours, to obtain a liquid polyisoprene containing hydroxyl groups, and the functional group content is 0.52 mmol / g.

[0106] (2) Preparation of multi-component composite MOFs slurry based on heat-cured adhesive material

[0107] The two kinds of organosilicon oligomers and liquid polyisoprene are mixed according to a mass ratio of 1:1:1, a defoaming agent, a compatibilizer, MOFs, wherein the MOFs are ZIF-8, MIL-101(Al), MIL-101(Cr), UIO-66 and ZIF-67, and the mass ratio is 1:1:1:1:1, the particle size is 800 mesh, the defoaming agent is polyether modified polysiloxane(DY-ET200), the solubilizing agent is hydroxypropyl methyl cellulose, the solid content of the MOFs is 70%, the content of the defoaming agent is 100 ppm, and the content of the solubilizing agent is 4.6%, under the condition of room temperature and nitrogen protection, the multiple MOFs are dispersed in the oligomer by stirring and ultrasonic homogenization, the temperature of the slurry system is controlled to be not more than 30°C, the water content is ≤30 ppm, the stirring time is 30 minutes, a polymer-based multi-component composite MOFs slurry is prepared, and the viscosity of the slurry is 10 Pa.S(room temperature). Then, a curing agent ethylenediamine and a catalyst dibutyltin dilaurate are added, the content of the curing agent is 10%, and the content of the catalyst is 30 ppm.

[0108] (3) Curing process and preparation of multi-component composite MOFs film material

[0109] The slurry was spin-coated on a glass or Teflon plate substrate to control the film thickness to 100-130 microns, cured at 60°C for 60 seconds, and then left to stand for 180 minutes to prepare a film with a size of 200 x 5000.

[0110] (4) Nuclear waste water treatment application

[0111] The prepared MOFs film was used for nuclear waste water treatment, specifically by placing the MOFs film in waste water containing Sr, Co, U, Th, Ag, Cs, etc. for 7 hours, with a total ion concentration of about 180 mg / L, and removing 93% of the ions by adsorption.

[0112] Example 6

[0113] (1) Synthesis and structure control of thermally cured oligomer-based adhesive material

[0114] An epoxy silicone oligomer was obtained by addition reaction of allyl glycidyl ether and hydrogen-containing silicone oil, with a molar ratio of carbon-carbon double bond to silicon-hydrogen bond of 1:1, at a reaction temperature of 45°C for 50 minutes, a molecular weight of 860, and a functional group content of 0.23 mmol / g; an amine silicone oligomer was obtained by addition reaction of 1-amino-10-undecene and hydrogen-containing silicone oil, with a molar ratio of carbon-carbon double bond to silicon-hydrogen bond of 1:1, at a reaction temperature of 35°C for 40 minutes, a molecular weight of 930, and a functional group content of 0.26 mmol / g.

[0115] A lithium initiator was used, with hexane as the solvent, and the butadiene monomer and comonomer 7-methyl-1,6-octadiene were added in two portions, with the second portion of butadiene monomer and comonomer added after the first portion of monomer was completely reacted, a mass ratio of the two portions of 1:1, and a total comonomer content of 5.0% of butadiene; the reaction temperature was controlled at 40°C, and the reaction time was 180 minutes, to obtain a liquid polybutadiene with a molecular weight of 1100 and a 1,4-content of ≥92%; benzeneperozoic acid was slowly added dropwise to the above-prepared liquid polybutadiene, with a molar ratio of carbon-carbon double bond to benzeneperozoic acid of 10:1, and the reaction temperature was slowly increased to 40°C, and the reaction time was 4 hours, to obtain a liquid polymer containing epoxy groups, with a functional group content of 0.58 mmol / g.

[0116] (2) Preparation of multi-element composite MOFs slurry based on thermally cured adhesive material

[0117] The two kinds of silicone oligomers and liquid polybutadiene are mixed according to a mass ratio of 1:1:1.5, a defoaming agent, a compatibilizer, MOFs, the MOFs being MIL-101(Al), MIL-101(Fe), MIL-101(Cr), UIO-66 and ZIF-67, a mass ratio of 1:1:1:1:1, a particle size of 800 mesh, the defoaming agent being polyether modified polysiloxane (DY-ET200), the solubilizer being hydroxypropyl methyl cellulose, a solid content of the MOFs being 80%, a content of the defoaming agent being 100 ppm, a content of the solubilizer being 4.5%, the various MOFs being dispersed in the oligomers by stirring and ultrasonic homogenization under the condition of room temperature and nitrogen protection, the temperature of the slurry system being controlled to be not more than 30°C, the water content being ≤30 ppm, the stirring time being 30 minutes, a polymer-based multi-element composite MOFs slurry being prepared, the viscosity of the slurry being 15 Pa.S (at room temperature). Then, a curing agent 2-methyl pentanediamine and a catalyst dibutyl tin dilaurate are added, the content of the curing agent being 10%, the content of the catalyst being 80 ppm.

[0118] (3) Curing process and preparation of multi-element composite MOFs film material

[0119] The slurry is spin-coated on a glass or tetrafluoro plate substrate, the film thickness being controlled to be 100-130 microns, the film being cured at 60°C for 60 seconds and then being left to stand for 300 minutes, a film with a size of 200x5000 being prepared.

[0120] (4) Nuclear waste water treatment application

[0121] The prepared MOFs film is used for nuclear waste water treatment, specifically, the MOFs film is placed in waste water containing Sr, Co, U, Th, Ag, Cs and the like for 7 hours, the total ion concentration being about 180 mg / L, and the adsorption removal rate being 95%.

Claims

1. A method for preparing a multi-element composite MOFs membrane, characterized in that, The application relates to a preparation method of a multi-element composite MOFs film. Step one: preparing a bonding material, wherein the bonding material comprises a silicone oligomer with a functional group of epoxy, hydroxyl, isocyanate, amine group, mercapto, vinyl or siloxane and liquid polyisoprene or liquid polybutadiene containing an epoxy group, a hydroxyl group and an amine group; Step two: mixing the bonding material, MOFs, a curing agent, a catalyst, an antifoaming agent and a solubilizing agent in step one to obtain a MOFs slurry; Step three: coating the MOFs slurry in step two on a substrate to be cured to obtain the multi-element composite MOFs film.

2. The method for preparing a multi-component composite MOF membrane according to claim 1, characterized in that, The molecular weight of the silicone oligomer in step one is 200-2000, and the content of the functional group is 0.2-0.8 mmol / g.

3. The method of claim 1, wherein the MOFs membrane is a multi-element composite MOFs membrane. The molecular weight of the liquid polyisoprene or liquid polybutadiene in step one is 200-2000, the content of the functional group is 0.08-0.8 mmol / g, the 1,4-content of the liquid polyisoprene is greater than or equal to 96%, and the 1,4-content of the liquid polybutadiene is greater than or equal to 92%.

4. The method of claim 1, wherein the MOFs membrane is a multi-element composite MOFs membrane. The MOFs are ZIF-8, MIL-101 (Al, Fe, Cr), UIO-66 or ZIF-67, and the number of the MOFs is greater than or equal to 5.

5. The method of claim 1, wherein the MOFs membrane is a multi-element composite MOFs membrane. In the slurry in step two, the solid content of the MOFs is 20-80%, the content of the curing agent is 2-20%, the content of the catalyst is 20-200 ppm, the content of the antifoaming agent is 1-160 ppm, and the content of the solubilizing agent is 0.1-3%.

6. The method of claim 1, wherein the MOFs membrane is a multi-component composite MOFs membrane. The curing agent is an aliphatic amine, a polyisocyanate or a high-hydrogen silicone oil, and the catalyst is an organic tin or platinum; The antifoaming agent is a silicone and a polyether modified polysiloxane; The solubilizing agent is one or more of polyethylene glycol, lecithin, propylene glycol, polyvinylpyrrolidone and hydroxypropyl methyl cellulose.

7. The method of claim 1, wherein the MOFs membrane is a multi-component composite MOFs membrane. The curing temperature in step three is 30-60 DEG C, and the curing time is 5 s-60 s.

8. The multi-element composite MOFs film obtained by the preparation method in claim 1.

9. The multi-component composite MOFs film according to claim 8, wherein, The thickness of the multi-element composite MOFs film is 50-200 microns, and the size of the film is greater than or equal to 200*5000.

10. The multi-element composite MOFs film in claim 9 is applied to nuclear waste water treatment.

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