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US-12624144-B2 - Method for preparing hollow covalent organic framework materials

US12624144B2US 12624144 B2US12624144 B2US 12624144B2US-12624144-B2

Abstract

The present invention relates to a method for preparing a hollow covalent organic framework (COF) material and hollow COF material prepared by said method. Said method is characterized in including a monomer displacement step in the method, thereby obtaining the hollow COF material with a controllable particle size, wall thickness and/or specific surface area.

Inventors

  • Pingwei Liu
  • Wen-Jun WANG
  • Song Wang

Assignees

  • ZHEJIANG UNIVERSITY

Dates

Publication Date
20260512
Application Date
20200924

Claims (10)

  1. 1 . A method for preparing hollow COF material, comprising: a. subjecting trialdehyde monomer B3 and diamine monomer A2 to polycondensation to obtain a polycondensate B3A2, or subjecting dialdehyde monomer B2 and triamine monomer A3 to polycondensation to obtain a polycondensate B2A3; b. dissolving triamine monomer A3 into a solvent and adding modifiers AP and BP to obtain reaction solution 1; or dissolving trialdehyde monomer B3 into a solvent and adding modifiers AP and BP to obtain reaction solution 2, wherein said modifier AP is selected from aromatic aldehydes and aliphatic aldehydes, and said modifier BP is selected from aromatic amines and aliphatic amines; c. dispersing polycondensate B3A2 into the reaction solution 1, or dispersing polycondensate B2A3 into the reaction solution 2, and adding a catalyst to initiate a reaction, thereby obtaining a product in form of a precipitate; and d. after the reaction, separating the resulting product and drying to obtain the hollow COF material; wherein the concentration of said triamine monomer A3 or trialdehyde monomer B3 in the reaction solution 1 or 2 is 0.01-100 mM, the molar ratio of said modifier BP to trialdehyde monomer B3 or triamine monomer A3 is 0.01-200:1, and the molar ratio of said modifier AP to BP is 0.01-100:1.
  2. 2 . The method according to claim 1 , wherein said dialdehyde monomer B2 is selected from terephthalaldehyde, 2,5-dimethoxyterephthalaldehyde, and biphenyldicarboxaldehyde.
  3. 3 . The method according to claim 1 , wherein said triamine monomer A3 is selected from 1,3,5-tris(4-aminophenyl) benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 2,4,6-tris(4-aminophenyl)-pyridine, 2,4,6-tris(4-aminophenyl)-pyrimidine, and tris(4-aminophenyl)-amine.
  4. 4 . The method according to claim 1 , wherein said diamine monomer A2 is selected from 1,4-phenylene diamine, 2,5-dimethyl-1,4-phenylene diamine, tetramethyl-p-phenylendiamine, and benzidine.
  5. 5 . The method according to claim 1 , wherein said modifier AP is selected from benzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde, 4-methylbenzaldehyde, 4-tert-butylbenzaldehyde, 4-fluorobenzaldehyde, 1-naphthaldehyde, 2-naphthaldehyde, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, capronaldehyde, heptaldehyde, caprylaldehyde, and any mixtures thereof.
  6. 6 . The method according to claim 1 , wherein said modifier BP is selected from aniline, 2-chloroaniline, 3-chloroaniline, 4-chloroaniline, 1,3-benzothiazol-5-amine, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-tert-butylaniline, 4-fluoroaniline, 1-naphthylamine, 2-naphthylamine, methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, cyclohexylamine, and any mixture thereof.
  7. 7 . The method according to claim 1 , wherein trialdehyde monomer B3 are selected from 1,3,5-benzenetricarboxaldehyde, 1,3,5-tris(4-aldehydephenyl) benzene, 2,4,6-tris(4-aldehydephenyl)-1,3,5-triazine, 2,4,6-tris(4-aldehydephenyl)-pyridine, 2,4,6-tris(4-aldehydephenyl)-pyrimidine, and tris(4-aldehydephenyl)-amine.
  8. 8 . The method according to claim 1 , wherein the concentration of said triamine monomer A3 or trialdehyde monomer B3 in the reaction solution 1 or 2 is 0.2-25 mM.
  9. 9 . The method according to claim 1 , wherein the molar ratio of said modifier BP to trialdehyde monomer B3 or triamine monomer A3 is 0.5-50:1.
  10. 10 . The method according to claim 1 , wherein the molar ratio of said modifier AP to BP is 0.2-5:1.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a U.S. National Stage Application of PCT/CN2020/117511, filed 24 Sep. 2020, and which application is incorporated herein by reference. To the extent appropriate, a claim of priority is made to the above disclosed application. TECHNICAL FIELD The present invention relates to a method for preparing a hollow covalent organic framework (COF) material and hollow COF material prepared by said method. Said method is characterized in including monomer displacement step in the method, thereby obtaining the hollow COF material with a controllable particle size, wall thickness and/or specific surface area. BACKGROUND ART Covalent organic framework (COF) materials are known organic porous materials, which are crystalline materials with periodic regular hole structure formed from rigid organic monomers via covalent bonding, and have a wide variety of applications in catalysis, separation, storage, energy, drug release, and the like. The COFs prepared by conventional methods are generally of irregular solid spherical structure, unable to achieve a precise customization of micro-scale structure, which thus limits the application range thereof. The COFs having a hollow spherical structure and uniform particle size can realize the compounding with functional nanomaterials, and the performances of the COFs in the applications such as drug release, storage and the like are greatly improved. US20170247493A1 discloses a method for preparing hollow Schiff base COFs without template, but this method is merely suitable for some special monomers, and cannot regulate the wall thickness, particle size of the hollow COFs. CN104772088A discloses a method for preparing hollow COFs via a homogeneous reaction, but this method cannot regulate the size, wall thickness of the hollow COFs either. Content of Invention The inventor has found that the drawbacks of the prior art can be overcome by a monomer displacement strategy, thereby preparing hollow COF materials with controllable particle size, wall thickness and/or specific surface area, or modifying certain solid and hollow COF materials of the prior art, for example, changing the wall thickness and/or specific surface area thereof, and the like. Thus, on one aspect, present invention relates to a method for preparing a hollow COF material, comprising: 1) subjecting trialdehyde monomer B3 and diamine monomer A2 to polycondensation to obtain a polycondensate B3A2, or subjecting dialdehyde monomer B2 and triamine monomer A3 to polycondensation to obtain a polycondensate B2A3;2) dissolving triamine monomer A3 into a solvent and adding modifiers AP and BP to obtain reaction solution 1; or dissolving trialdehyde monomer B3 into a solvent and adding modifiers AP and BP to obtain reaction solution 2;3) dispersing the polycondensate B3A2 into the reaction solution 1, or dispersing the polycondensate B2A3 into the reaction solution 2, and adding a catalyst to initiate a reaction, thereby obtaining a product A3B3 in form of a precipitate; and4) after the reaction, separating resulting product A3B3 and dying to obtain the hollow COF material. The trialdehyde monomer B3 is the one known in the art for preparing COF materials, for example, which can be selected from (aromatic) trialdehydes and the derivates thereof, their examples include, but not limited to, 1,3,5-benzenetricarboxaldehyde, 2,4,6-trihydroxy-benzenetricarboxaldehyde, 1,3,5-tris(4-aldehydephenyl)benzene, 2,4,6-tris(4-aldehydephenyl)-1,3,5-triazine, 2,4,6-tris(4-aldehydephenyl)-pyridine, 2,4,6-tris(4-aldehydephenyl)-pyrimidine, tris(4-aldehydephenyl)-amine, 1,3,5-tris(4′-aldehyde[1,1′-biphenyl]-4-yl)-benzene, 1,3,5-tris(4′-aldehyde[1,1′-biphenyl]-4-yl)-1,3,5-triazine, 1,3,5-tris(4′-aldehyde[1,1′-biphenyl]-4-yl)-pyridine, 1,3,5-tris(4′-aldehyde[1,1′-biphenyl]-4-yl)-pyrimidine, 1,3,5-tris(4′-aldehyde[1,1′-biphenyl]-4-yl)-amine, and any mixtures thereof. In the present invention, preferred trialdehyde monomer B3 are selected from benzenetricarboxaldehyde, 1,3,5-tris(4-aldehydephenyl)benzene, 2,4,6-tris(4-aldehydephenyl)-1,3,5-triazine, 2,4,6-tris(4-aldehydephenyl)-pyridine, 2,4,6-tris(4-aldehydephenyl)-pyrimidine, and tris(4-aldehydephenyl)-amine. The monomers above are commercially available or prepared by the methods known in the art. The dialdehyde monomer B2 is the one known in the art for preparing COF materials, for example, which can be selected from (aromatic) dialdehydes and the derivates thereof, their examples include, but not limited to, terephthalaldehyde, biphenyldicarboxaldehyde, 2,5-dihydroxyterephthalaldehyde, 2,5-dimethoxyterephthalaldehyde, 2,3-dihydroxyterephthalaldehyde, 2,3-dimethoxyterephthalaldehyde, 2,5-dialkynoxyterephthalaldehyde, glyoxal, and any mixtures thereof. In the present invention, preferred dialdehyde monomer B2 are selected from terephthalaldehyde, 2,5-dimethoxyterephthalaldehyde, and biphenyldicarboxaldehyde. The monomers above are commerciall