Search

CN-121988177-A - Surface functionalization modification method of porous substrate and modified porous substrate

CN121988177ACN 121988177 ACN121988177 ACN 121988177ACN-121988177-A

Abstract

The application provides a porous substrate surface functionalization modification method and a modified porous substrate, and belongs to the field of membrane material design. The method comprises the steps of providing a porous substrate, contacting the porous substrate with an adhesion solution containing polyphenol compounds and proteins to form a bioadhesive layer on the surface of the porous substrate, sequentially contacting the porous substrate with the bioadhesive layer with a solution containing iron ions and copper ions to form a bimetal-phenolic network layer on the bioadhesive layer, contacting the porous substrate with the bimetal-phenolic network layer with a solution containing hydrophilic high molecular polymers to form a hydrogel layer on the surface of the bimetal-phenolic network layer, and obtaining the modified porous substrate with the composite functional coating. The porous substrate surface functionalization modification method and the modified porous substrate provided by the application can realize the high-efficiency separation of complex oily organic wastewater, pollutant degradation and membrane self-cleaning regeneration integrated treatment, and improve the universality and stability of the functional coating.

Inventors

  • GAO JUNKAI
  • CHEN YONGQI
  • CHEN YAN
  • WANG RUNJIE
  • MA KAI

Assignees

  • 浙江海洋大学

Dates

Publication Date
20260508
Application Date
20260120

Claims (10)

  1. 1. A method for functionally modifying a surface of a porous substrate, the method comprising: providing a porous substrate; contacting the porous substrate with an adhesion solution containing a polyphenol compound and a protein to form a bioadhesive layer on the surface of the porous substrate; sequentially contacting the porous substrate with the bioadhesive layer with a solution containing iron ions and copper ions to form a bimetal-phenolic network layer on the bioadhesive layer; And (3) contacting the porous substrate with the bimetal-phenolic aldehyde network layer with a solution containing a hydrophilic high molecular polymer, and forming a hydrogel layer on the surface of the bimetal-phenolic aldehyde network layer to obtain the modified porous substrate with the composite functional coating.
  2. 2. The method of claim 1, wherein the porous substrate comprises a polymeric microfiltration membrane comprising a polyvinylidene fluoride membrane and a polytetrafluoroethylene membrane and a natural cellulosic material comprising palm bark.
  3. 3. The method of claim 2, wherein when the porous substrate is palm bark, the pretreatment is performed prior to use, the pretreatment comprising: Cutting palm bark into preset size, soaking in 80deg.C 2wt% sodium hydroxide aqueous solution for 2-3 hr, washing with distilled water to neutrality, soaking in 80deg.C 2wt% sodium chlorite aqueous solution for 5-7 hr, washing, and drying.
  4. 4. The method of claim 1, wherein the polyphenol compound is tannic acid and the protein is regenerated silk fibroin, and the forming of the bioadhesive layer on the porous substrate surface comprises: immersing the porous substrate in an aqueous solution containing 4.5-5.5wt% tannic acid and 3-5wt% regenerated silk fibroin for 38-41min.
  5. 5. The method of claim 4, wherein the bioadhesive layer is formed by immersing the porous substrate in an aqueous solution containing 5wt% tannic acid and 4wt% regenerated silk fibroin for 40 minutes.
  6. 6. The method of claim 1, wherein the solutions containing iron ions and copper ions are FeCl 3 solution and CuCl 2 solution, respectively, and the forming the bimetallic-phenolic network layer on the bioadhesive layer comprises: Soaking the porous substrate with the bioadhesive layer in a 33-34g/L FeCl 3 solution for 15-30min, washing with distilled water, soaking the washed porous substrate in a 12-13g/L CuCl 2 solution for 15-30min, and washing again.
  7. 7. The method of claim 6, wherein the porous substrate is immersed in 33.3g/L FeCl 3 solution for 20 minutes, rinsed with distilled water, and immersed in 12.65g/L CuCl 2 solution for 20 minutes when forming the bimetallic-phenolic network layer.
  8. 8. The method of claim 1, wherein the solution containing a hydrophilic high molecular polymer is a polyvinyl alcohol solution, and the forming of a hydrogel layer on the surface of the bimetallic-phenolic network layer comprises: Immersing the porous substrate with the bimetal-phenolic network layer in 0.4-1.0wt% polyvinyl alcohol solution for 15-30 min, taking out, and drying at room temperature for 1.5-2.5 h.
  9. 9. The method of claim 8, wherein the porous substrate is immersed in a 0.5wt% polyvinyl alcohol solution for 20 minutes, removed and dried at room temperature for 2 hours when the hydrogel layer is formed.
  10. 10. The modified porous substrate is characterized in that the modified porous substrate is prepared by the method of any one of claims 1 to 9, and the surface of the modified porous substrate is provided with a composite from inside to outside: A bioadhesive layer comprising a complex of a polyphenol compound and a protein; A bimetal-phenolic aldehyde network layer formed by coordination of the polyphenol compound with iron ions and copper ions; A hydrogel layer formed by crosslinking a hydrophilic high molecular polymer through hydrogen bonds; The contact angle of the surface of the modified porous substrate to water is 0 DEG, the contact angle of the surface of the modified porous substrate to oil under water is more than 120 DEG, and the surface coating of the modified porous substrate has photo-Fenton-like catalytic activity in the presence of visible light and hydrogen peroxide.

Description

Surface functionalization modification method of porous substrate and modified porous substrate Technical Field The application relates to the technical field of membrane material design, in particular to a porous substrate surface functionalization modification method and a modified porous substrate. Background Industrial oily wastewater has complex composition and usually contains various pollutants such as emulsified oil drops, soluble dyes, antibiotics and the like, and forms a serious threat to the water ecosystem and human health. The membrane separation technology is regarded as one of the effective means for treating the wastewater because of the characteristics of high efficiency, energy saving, simple operation and the like, however, the traditional separation membrane mainly depends on a physical interception mechanism, and is difficult to synchronously remove soluble organic pollutants, and in the filtration process, emulsified oil drops easily form an oil cake layer on the surface of the membrane, so that the membrane flux is rapidly reduced and irreversibly polluted, and the long-term operation efficiency and the service life of the membrane are seriously restricted. In order to improve the antifouling capacity and the comprehensive performance of the film, researchers are devoted to developing a surface modification strategy with super-hydrophilicity and self-cleaning functions. The photocatalytic capability of the surface of the membrane is endowed, so that the membrane can degrade organic pollutants and realize self-cleaning during separation, and the membrane becomes an important research direction. For example, it has been studied to combine Tannic Acid (TA) with polyvinylpyrrolidone (PVP), build a hydrogel coating in combination with an iron-based photoFenton component, or prepare a composite membrane using a photocatalytic material such as MXene, degrade the dye and restore flux while separating the emulsified oil. These work demonstrate the potential to integrate interfacial soil resistance with light driven self-cleaning functions on the membrane surface. However, the existing membrane surface modification strategies still face two major challenges, namely poor universality of the base material, most modification methods are developed aiming at specific base materials, and firm and uniform functional modification on high-hydrophobicity and low-surface-energy inert polymers such as polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE) and the like or natural porous materials with complex structures is difficult to realize. Secondly, the long-term stability of the coating is insufficient, and many functional coatings are easy to swell, recombine or lose active components in an aqueous phase environment, so that the structural damage and the performance attenuation are caused. In recent years, polyphenol chemistry inspired by natural mussel adhesion, especially coordination and assembly of Tannic Acid (TA) and metal ions, provides a new idea for constructing functional coatings. TA can form a metal-phenolic network (MPN) with Fe (III) and other metal ions rapidly, but a single metal system still has limitations in terms of catalytic efficiency and stability. Meanwhile, how to stably and universally anchor the active network to various porous substrates and further integrate an outer layer structure with anti-pollution and protection effects so as to realize the multi-function coordination of adhesion-catalysis-protection is still a key scientific problem and technical bottleneck to be solved. Therefore, development of a multifunctional modification strategy which has strong universality of a base material and high stability of a coating and can synchronously realize efficient oil-water separation, deep degradation of pollutants and self-cleaning regeneration of a membrane is urgently needed. Disclosure of Invention In view of the above, the application provides a method for modifying the surface of a porous substrate and a modified porous substrate, which are used for solving the problems that the existing membrane material cannot realize high-efficiency separation and deep degradation of pollutants and self-cleaning regeneration of the surface of the membrane synchronously in complex oily organic wastewater treatment, and the functional coating has poor universality and insufficient stability. Specifically, the application is realized by the following technical scheme: The first aspect of the application provides a method for modifying the surface of a porous substrate by functionalization, comprising the following steps: providing a porous substrate; contacting the porous substrate with an adhesion solution containing a polyphenol compound and a protein to form a bioadhesive layer on the surface of the porous substrate; sequentially contacting the porous substrate with the bioadhesive layer with a solution containing iron ions and copper ions to form a bimetal-phenolic network