Composite reverse osmosis membrane based on polyarylether sulphone-based membrane containing phthalazinone structure and preparation method of composite reverse osmosis membrane

Abstract

The invention belongs to a separation membrane preparation technology, and discloses a composite reverse osmosis membrane based on a poly (aryl ether sulfone) base membrane containing a phthalazinone structure and a preparation method of the composite reverse osmosis membrane. The preparation method comprises the following steps: selecting a poly (aryl ether sulfone) containing the phthalazinone structure and a chloromethylated poly (aryl ether sulfone) blended ultrafiltration membrane as the base membrane; an ultrathin polyamide separation layer is compounded on the surface of an ultrafiltration base membrane by adopting an interfacial polymerization method, wherein the separation layer is prepared from polyamine and an acyl chloride monomer through interfacial polymerization. Polyamine in the water phase reacts with chloromethyl on the surface of the base membrane, so that chemical bond combination between the base membrane and the active layer is realized, and the stability of the reverse osmosis membrane is greatly improved. Besides, the phthalazinone structure-containing copolymer aryl ether sulfone molecular chain in the base membrane contains a full aromatic ring distorted non-coplanar phthalazinone structure, so that the composite reverse osmosis membrane has high glass transition temperature and excellent chemical stability, and the prepared composite reverse osmosis membrane has the characteristic of high temperature resistance. Powerful reference is provided for solving the problem of insufficient stability of the reverse osmosis membrane.

Description

Technical Field

[0001] The present invention belongs to the technology of preparing separation membranes, and relates to a composite reverse osmosis membrane based on a polyarylethersulfone substrate membrane containing a phthalazinone structure and a method for preparing the same. Background Art

[0002] As an important branch of membrane separation technology, the development of reverse osmosis membranes can be traced back to the 1950s. In 1953, American scientists Reid and Bretron first proposed the concept of reverse osmosis. By using the selective separation effect of a semi-permeable membrane, under the condition of higher than the osmotic pressure of the solution, driven by an external pressure, the solvent (usually water) flows through the membrane from the side with a high concentration of solute to the low-concentration side, thereby realizing the efficient separation of solute and solvent. In 1960, Loeb and Sourirajan prepared the first-generation reverse osmosis membrane (asymmetric cellulose acetate membrane) by the phase inversion method. This membrane has an asymmetric structure with a dense surface layer and a porous support layer, and the membrane separation performance is significantly improved, laying an important foundation for modern reverse osmosis technology. In the 1970s, Cadotte et al. formed an ultrathin separation layer on the surface of the substrate membrane by the interfacial polymerization method, and developed a polyamide composite reverse osmosis membrane. This new composite structure has the advantages of high salt rejection rate and high flux, and gradually replaces the cellulose acetate membrane as the mainstream technology. With the progress of material science and preparation technology, the application of composite reverse osmosis membranes in the fields of seawater desalination, wastewater treatment, food and medicine, etc. has been continuously deepened, promoting the continuous innovation and development of membrane separation technology.

[0003] In special fields such as chemical wastewater treatment, there are relatively high requirements for the high temperature resistance and acid and alkali resistance of composite reverse osmosis membranes. At present, most commercial composite reverse osmosis membranes face the problem of insufficient stability. First, the substrate membrane materials of commercial composite reverse osmosis membranes will undergo polymer chain breakage when in long-term contact with oxidants or extreme pH solutions; second, under high pressure and temperature fluctuations, the active layer and the substrate membrane of the composite reverse osmosis membrane may peel off. These stability problems not only shorten the membrane life, but also limit the application of commercial composite reverse osmosis membranes in various harsh environments. In recent years, researchers have begun to adopt the method of polymer blending, combining the advantages of different materials, to prepare high-performance substrate membranes for composite reverse osmosis membranes, pointing out a new direction for the development of composite reverse osmosis membranes. Wei Ju et al. (Acta Polymerica Sinica, 2006, (2): 298-302) prepared a blend ultrafiltration substrate membrane of heterophthalic polyethersulfone ketone / sulfonated heterophthalic polyethersulfone ketone by the solution blending method, and prepared a composite reverse osmosis membrane therefrom. Among them, both polymers contain a phthalazinone structure with a fully aromatic ring twisted non-coplanar, which has good heat resistance and improves the heat resistance of the substrate membrane; sulfonated heterophthalic polyethersulfone ketone contains hydrophilic sulfonic acid groups, which improve the hydrophilicity of the ultrafiltration substrate membrane, thereby improving the water flux of the composite reverse osmosis membrane. However, at present, there is no strong interaction between the substrate membrane and the active separation layer of the composite reverse osmosis membrane, and the bonding strength still needs to be improved to improve its stability.

[0004] The present invention uses chloromethylated polyarylethersulfone and polyarylethersulfone containing phthalazinone structure as the base membrane materials, and prepares a polyamide composite reverse osmosis membrane based on the polyarylethersulfone base membrane containing phthalazinone structure by the interfacial polymerization method. Among them, the polyarylethersulfone containing phthalazinone structure has a relatively high glass transition temperature, which is beneficial to maintaining the heat resistance of the base membrane. The introduction of chloromethyl into the base membrane can react with the aqueous amine monomer, so that the base membrane support layer and the active layer of the composite membrane are connected by chemical bonds, which is expected to improve the stability of the reverse osmosis membrane. Summary of the Invention

[0005] The present invention belongs to the technology of preparing separation membranes, and provides a method for preparing a polyamide composite reverse osmosis membrane based on a polyarylethersulfone base membrane containing phthalazinone structure.

[0006] Technical solution of the present invention:

[0007] A composite reverse osmosis membrane based on a polyarylethersulfone base membrane containing phthalazinone structure, using a blend membrane of chloromethylated polyarylethersulfone and polyarylethersulfone containing phthalazinone structure as the base membrane;

[0008] 1) The structural formula of chloromethylated polyarylethersulfone is:

[0009]

[0010] Wherein X is The structural formula of polyarylethersulfone containing phthalazinone structure is:

[0011]

[0012] Wherein Y is Wherein R1, R2, R3, and R4 are hydrogen atoms, halogen atoms, methyl groups or aryl groups, and the four are the same or different.

[0013] A method for preparing a composite reverse osmosis membrane based on a polyarylethersulfone base membrane containing phthalazinone structure, the steps are as follows:

[0014] Select a blend ultrafiltration membrane of chloromethylated polyarylethersulfone and polyarylethersulfone containing phthalazinone structure as the base membrane; dissolve a polyamine in deionized water, and after complete dissolution, add an aqueous phase additive to prepare an aqueous phase solution; wherein, the polyamine accounts for 0.1-5% of the mass of the aqueous phase solution, and the aqueous phase additive accounts for 0-5% of the mass of the aqueous phase solution; dissolve the acyl chloride monomer in an alkane organic solvent to prepare an oil phase solution, wherein the acyl chloride monomer accounts for 0.01-5% of the mass of the oil phase solution;

[0015] Under the conditions that the ambient temperature is 10 - 50 °C and the humidity is 20 - 80%, soak the dry base film in the aqueous solution for 0.5 - 20 min to allow the base film to fully adsorb the aqueous solution, and let the polyamine in the aqueous solution react with the chloromethyl groups on the surface of the base film; take out the base film, drain it in the air until the excess aqueous solution on the film surface is removed; then place it in the organic phase solution for interfacial polymerization reaction. After polymerizing for 5 - 200 s at a temperature of 10 - 80 °C, take it out and drain it in the air to obtain the nascent composite membrane; perform post-treatment on the nascent composite membrane at 20 - 120 °C for 0 - 60 min to obtain a composite reverse osmosis membrane based on a polyarylethersulfone base film containing a phthalazinone structure.

[0016] The above-mentioned chloromethylated polyarylethersulfone and polyarylethersulfone blend ultrafiltration membrane containing a phthalazinone structure is prepared by solution blending of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure and using the phase inversion method, where the mass ratio of chloromethylated polyarylethersulfone to polyarylethersulfone containing a phthalazinone structure is 1:1 - 1:50; the specific preparation process is as follows:

[0017] 1) Add additives and solvents to chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure, mix and stir until completely dissolved to obtain a homogeneous and stable casting solution; among them, the total mass of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure accounts for 5 - 30% of the mass fraction of the casting solution, the additive accounts for 0 - 30% of the mass fraction of the casting solution, and the solvent accounts for 40 - 95% of the mass fraction of the casting solution;

[0018] 2) Scrape the film under the conditions that the ambient temperature is 10 - 50 °C and the humidity is 20 - 80%; after the solvent in the casting solution evaporates for 0 - 5 min, put it into a gel bath at a temperature of 0 - 50 °C, where the additive in the gel bath accounts for 0 - 10 wt%, and the gel forms an ultrafiltration membrane. Soak it in water to wash away the solvent and additives to obtain the chloromethylated polyarylethersulfone and polyarylethersulfone blend ultrafiltration membrane containing a phthalazinone structure.

[0019] Among them,

[0020] The above-mentioned additive is one or more mixtures of ethylene glycol monomethyl ether, ethanol, ethylene glycol, glycerol, polyethylene glycol, and polyvinylpyrrolidone;

[0021] The above-mentioned solvent is one or more mixtures of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and dimethyl sulfoxide;

[0022] The additive in the above-mentioned gel bath is one or more mixtures of inorganic salts, organic solvents, acids, and bases;

[0023] The inorganic salt is NaCl, LiCl or CaCl2; the organic solvent is ethanol or isopropanol; the acid is HCl; the base is NaOH.

[0024] The polyamine is one or a mixture of two or more of m-phenylenediamine, p-phenylenediamine, biphenylenediamine (such as 4,4'-diaminobiphenyl), and melamine.

[0025] The aqueous phase additive is one or a mixture of two or more of triethylamine, sodium carbonate, sodium dodecyl sulfate, Tween-80, and camphorsulfonic acid.

[0026] The acyl chloride monomer is one or a mixture of two or more of isophthaloyl chloride, terephthaloyl chloride, trimellitic trichloride, and pyromellitic tetrachloride.

[0027] The alkane organic solvent is one or a mixture of two or more of n-hexane, cyclohexane, n-heptane, n-decane, and isoparaffin.

[0028] Advantages of the present invention:

[0029] (1) In the present invention, a blend film of chloromethylated polyarylether sulfone and polyarylether sulfone containing a phthalazinone structure is used as the base film. The surface of the base film contains chloromethyl groups. When immersed in an aqueous solution of polyamine, the chloromethyl groups react with amino groups. After interfacial polymerization, chemical bonding can be achieved between the base film support layer and the active layer of the composite membrane, improving the stability of the reverse osmosis membrane.

[0030] (2) The present invention prepares a composite reverse osmosis membrane based on a polyarylether sulfone base film containing a phthalazinone structure. The polyarylether sulfone containing a phthalazinone structure has a relatively high glass transition temperature, which is beneficial to improving the heat resistance of the base film. Blending chloromethylated polyarylether sulfone and polyarylether sulfone containing a phthalazinone structure and introducing chloromethyl groups on the surface of the base film enable the chloromethyl groups to react with polyamines in the aqueous phase, achieving chemical bonding between the base film and the active layer, thereby being beneficial to improving the bonding stability between the support layer and the separation layer of the reverse osmosis membrane and further enhancing the heat resistance of the composite reverse osmosis membrane. Description of the drawings

[0031] Figure 1 is the 1H NMR spectrum of CMPES before and after amination treatment.

[0032] Figure 2 is the infrared spectrum of the CMPES / PPBES base film before and after amination treatment. Detailed implementation manners

[0033] The following further illustrates the detailed implementation manners of the present invention in combination with the drawings and technical solutions.

[0034] Example 1

[0035] Ultrafiltration membranes were prepared by blending biphenol-based heterocyclic naphthalene biphenyl copolyarylethersulfone (PPBES) and chloromethylated polyethersulfone (CMPES). Their structural formulas are as follows:

[0036]

[0037] Weighed out the dried biphenol-based heterocyclic naphthalene biphenyl copolyarylethersulfone (PPBES, 3.0 g) and chloromethylated polyethersulfone (CMPES, 0.2 g), with the solvent being N,N-dimethylacetamide (13.6 g). Added the additive ethylene glycol monomethyl ether (3.2 g), and stirred until the polymer was completely dissolved to obtain a homogeneous and stable casting solution. Under the conditions of an ambient temperature of 25 °C and a humidity of 30%, the casting solution with a certain thickness was blade-coated on a glass plate or a non-woven fabric support. It was exposed to the air, and the solvent evaporation time was 10 s. Then it was immersed in a 25 °C deionized water gel bath for phase inversion to form a membrane. After washing away the solvent and the additive, a blended ultrafiltration membrane of chloromethylated polyethersulfone and biphenol-based heterocyclic naphthalene biphenyl copolyarylethersulfone was obtained.

[0038] A blended ultrafiltration membrane of chloromethylated polyarylethersulfone (CMPES) / polyarylethersulfone containing a phthalazinone structure (PPBES-1) with a mass ratio of CMPES to PPBES of 1:15 was prepared. The rejection rate of the ultrafiltration membrane for bovine serum albumin (BSA) could reach 99.0%, and the water flux could reach 290.5 L·m -2· h -1 。

[0039] Weighed out m-phenylenediamine (MPD, 2.0 g) and dissolved it in 95.9 g of deionized water. After complete dissolution, added sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g), and stirred at room temperature until completely dissolved to prepare an aqueous phase solution. The mass fraction of MPD in the aqueous phase solution was 2.0%, the mass fraction of SDS in the aqueous phase solution was 0.1%, and the mass fraction of TEA in the aqueous phase solution was 2.0%. Weighed out trimesoyl chloride (TMC, 0.15 g) and dissolved it in 99.85 g of n-hexane organic solvent, and stirred at room temperature until completely dissolved to prepare an organic phase solution. The mass fraction of acyl chloride in the oil phase solution was 0.15%.

[0040] Under the conditions of an environmental temperature of 25 °C and a humidity of 30%, using the CMPES / PPBES-1 blended ultrafiltration membrane as the base membrane, the base membrane was immersed in the aqueous solution for 1 min to allow it to fully adsorb the aqueous solution, and the polyamine in the aqueous phase reacted with the chloromethyl groups on the surface of the base membrane; the base membrane was taken out, drained in the air, and the excess aqueous solution on the membrane surface was removed; the above-mentioned membrane was placed in the organic phase solution for interfacial polymerization reaction. After 60 s of polymerization, it was taken out and drained in the air to obtain the nascent composite membrane; at 60 °C, the nascent composite membrane was treated for 10 min to obtain a polyamide composite reverse osmosis membrane based on the poly(arylene ether sulfone) base membrane containing phthalazinone structure. At 25 °C and an operating pressure of 1.6 MPa, the water flux of the reverse osmosis membrane was 26.3 L·m -2 ·h -1 , and the desalination rate for NaCl was 99.2%.

[0041] The structures of the CMPES and CMPES / PPBES ultrafiltration base membranes before and after immersion in the aqueous solution were characterized. From nuclear magnetic ( Figure 1 ) and infrared spectra ( Figure 2 ), it was known that the chloromethyl groups on the surface of the CMPES / PPBES base membrane reacted with the amino groups of m-phenylenediamine. The composite reverse osmosis membrane was treated in boiling water for 30 min. After the boiling water treatment, the water flux of the reverse osmosis membrane increased from 26.3 L·m -2 ·h -1 to 34.1 L·m -2 ·h -1 , and the desalination rate only decreased from 99.2% to 99.0%, and the desalination rate basically remained stable. This indicates that the composite reverse osmosis membrane has good heat resistance and stability.

[0042] Comparative Example 1

[0043] Using the PPBES ultrafiltration membrane prepared in Example 1 as the base membrane, the rejection rate of the ultrafiltration membrane for BSA was 99.4%, and the water flux was 285.2 L·m -2 ·h -1 . Weigh 2.0 g of m-phenylenediamine (MPD) and dissolve it in 95.9 g of deionized water. After complete dissolution, add 0.1 g of sodium dodecyl sulfate (SDS) and 2.0 g of triethylamine (TEA), and stir at room temperature until completely dissolved to prepare an aqueous solution. The mass fraction of MPD in the aqueous solution is 2.0%, the mass fraction of SDS in the aqueous solution is 0.1%, and the mass fraction of TEA in the aqueous solution is 2.0%; weigh 0.15 g of trimesoyl chloride (TMC) and dissolve it in 99.85 g of n-hexane organic solvent, and stir at room temperature until completely dissolved to prepare an organic phase solution. The mass fraction of acyl chloride in the oil phase solution is 0.15%.

[0044] Under the conditions of an environmental temperature of 25 °C and a humidity of 30%, the PPBES base film was immersed in an aqueous solution for 1 min to allow it to fully adsorb the aqueous solution. Then, the base film was taken out, drained in air, and the excess aqueous solution on the film surface was removed. The above-mentioned film was placed in an organic phase solution for interfacial polymerization reaction. After 60 s of polymerization, it was taken out and drained in air to obtain a nascent composite membrane. At 60 °C, the nascent composite membrane was post-treated for 10 min to obtain a polyamide composite reverse osmosis membrane. When the operating pressure is 1.6 MPa and the operating temperature is 25 °C, the water flux of the reverse osmosis membrane is 15.0 L·m -2 ·h -1 , and the desalination rate of the membrane for NaCl is 97.0%.

[0045] By comparing Example 1 and Comparative Example 1, it can be seen that the water flux and desalination rate of the composite reverse osmosis membrane prepared with the blend ultrafiltration membrane of chloromethylated polyethersulfone and biphenol-based heterocyclic naphthalene-based copolyarylethersulfone as the base film are both higher than those of the reverse osmosis membrane prepared with the biphenol-based heterocyclic naphthalene-based copolyarylethersulfone ultrafiltration membrane as the base film. This shows that the composite reverse osmosis membrane prepared with the blend ultrafiltration membrane of chloromethylated polyethersulfone and biphenol-based heterocyclic naphthalene-based copolyarylethersulfone as the base film exhibits higher osmotic selectivity.

[0046] Example 2

[0047] Prepare a blend ultrafiltration membrane of chloromethylated polyarylethersulfone / polyarylethersulfone containing a phthalazinone structure (CMPES / PPBES-2) according to the preparation method of Example 1. Among them, the mass ratio of chloromethylated polyarylethersulfone (CMPES) to polyarylethersulfone containing a phthalazinone structure (PPBES) is 1:30. The rejection rate of the ultrafiltration membrane for BSA is 99.6%, and the water flux is 301.9 L·m -2· h -1 .

[0048] Weigh metaphenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g), and stir at room temperature until completely dissolved to prepare an aqueous solution. Among them, the mass fraction of MPD in the aqueous solution is 2.0%, the mass fraction of SDS in the aqueous solution is 0.1%, and the mass fraction of TEA in the aqueous solution is 2.0%; Weigh trimesoyl chloride (TMC, 0.15 g) and dissolve it in 99.85 g of n-hexane organic solvent, and stir at room temperature until completely dissolved to prepare an organic phase solution. Among them, the mass fraction of acyl chloride in the oil phase solution is 0.15%.

[0049] Under the conditions of an environmental temperature of 25 °C and a humidity of 30%, using the CMPES / PPBES-2 blended ultrafiltration membrane as the base membrane, the base membrane was immersed in the aqueous solution for 1 min to allow it to fully adsorb the aqueous solution, and the polyamine in the aqueous phase reacted with the chloromethyl groups on the surface of the base membrane; the base membrane was taken out, drained in air, and the excess aqueous solution on the membrane surface was removed; the above-mentioned membrane was placed in the organic phase solution for interfacial polymerization reaction. After polymerization for 60 s, it was taken out and drained in air to obtain the nascent composite membrane; the nascent composite membrane was post-treated at 60 °C for 10 min to obtain a polyamide composite reverse osmosis membrane based on a poly(arylene ether sulfone) base membrane containing a phthalazinone structure. When the operating pressure was 1.6 MPa and the operating temperature was 25 °C, the water flux of the reverse osmosis membrane was 24.1 L·m -2 ·h -1 , and the rejection rate of the membrane for NaCl was 99.1%.

[0050] Example 3

[0051] Prepare the CMPES / PPBES-1 blended ultrafiltration membrane according to the preparation method of Example 1;

[0052] Weigh 2.0 g of m-phenylenediamine (MPD) and dissolve it in 95.9 g of deionized water. After complete dissolution, add 0.1 g of sodium dodecyl sulfate (SDS) and 2.0 g of triethylamine (TEA), and stir at room temperature until completely dissolved to prepare an aqueous solution. The mass fraction of MPD in the aqueous solution is 2.0%, the mass fraction of SDS in the aqueous solution is 0.1%, and the mass fraction of TEA in the aqueous solution is 2.0%; weigh 0.25 g of trimesoyl chloride (TMC) and dissolve it in 99.75 g of n-hexane organic solvent, and stir at room temperature until completely dissolved to prepare an organic phase solution, where the mass fraction of the acyl chloride in the oil phase solution is 0.25%.

[0053] Under the conditions of an environmental temperature of 25 °C and a humidity of 30%, using the CMPES / PPBES-1 blended ultrafiltration membrane as the base membrane, immerse it in the aqueous solution for 1 min to allow the base membrane to fully adsorb the aqueous solution, and the polyamine in the aqueous phase reacts with the chloromethyl groups on the surface of the base membrane; take out the base membrane, drain it in air and remove the excess aqueous solution on the membrane surface; place the above-mentioned membrane in the organic phase solution for interfacial polymerization reaction. After polymerization for 60 s, take it out and drain it in air to obtain the nascent composite membrane; post-treat the nascent composite membrane at 60 °C for 10 min to obtain a polyamide composite reverse osmosis membrane based on a poly(arylene ether sulfone) base membrane containing a phthalazinone structure. When the operating pressure is 1.6 MPa and the operating temperature is 25 °C, the water flux of the reverse osmosis membrane is 25.9 L·m -2 ·h -1 , and the desalination rate of the membrane for NaCl is 99.3%.

[0054] Example 4

[0055] Prepare the CMPES / PPBES-1 blended ultrafiltration membrane according to the preparation method of Example 1;

[0056] Weigh m-phenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g), and stir at room temperature until completely dissolved to prepare an aqueous solution. The mass fraction of MPD in the aqueous solution is 2.0%, the mass fraction of SDS in the aqueous solution is 0.1%, and the mass fraction of TEA in the aqueous solution is 2.0%; Weigh trimesoyl chloride (TMC, 0.15 g) and dissolve it in 99.85 g of n-hexane organic solvent, and stir at room temperature until completely dissolved to prepare an organic solution. The mass fraction of acyl chloride in the oil phase solution is 0.15%.

[0057] Under the conditions of an environmental temperature of 25 °C and a humidity of 30%, using the CMPES / PPBES-1 blended ultrafiltration membrane as the base membrane, immerse the base membrane in the aqueous solution for 1 min to allow it to fully adsorb the aqueous solution, and the polyamine in the aqueous phase reacts with the chloromethyl on the surface of the base membrane; Take out the base membrane, drain it in the air and remove the excess aqueous solution on the membrane surface; Immerse the above membrane in the organic solution for interfacial polymerization reaction. After 40 s of polymerization, take it out and drain it in the air to obtain a nascent composite membrane; At 60 °C, post-treat the nascent composite membrane for 10 min to obtain a polyamide composite reverse osmosis membrane based on a phthalazinone-containing polyarylethersulfone base membrane. When the operating pressure is 1.6 MPa and the operating temperature is 25 °C, the water flux of the reverse osmosis membrane is 31.2 L·m -2 ·h -1 , and the salt rejection rate of the membrane for NaCl is 97.1%.

Claims

1. A composite reverse osmosis membrane based on a phthalazinone-containing polyarylether sulfone-based membrane, characterized in that, Using a blend membrane of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure as the base membrane; The structural formula of chloromethylated polyarylethersulfone is: where X is The structural formula of polyarylethersulfone containing a phthalazinone structure is: where Y is Among them, R1, R2, R3, and R4 are hydrogen atoms, halogen atoms, methyl groups or aryl groups, and the four are the same or different.

2. A preparation method of a composite reverse osmosis membrane based on a phthalazinone-containing polyarylethersulfone-based membrane, characterized in that, The steps are as follows: Select a blend ultrafiltration membrane of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure as the base membrane; dissolve a polyamine in deionized water, and after complete dissolution, add an aqueous phase additive to form an aqueous phase solution; among them, the mass fraction of the polyamine in the aqueous phase solution is 0.1-5%, and the mass fraction of the aqueous phase additive in the aqueous phase solution is 0-5%; dissolve an acyl chloride monomer in an alkane organic solvent to form an oil phase solution, and the mass fraction of the acyl chloride monomer in the oil phase solution is 0.01-5%; Under the conditions of an environmental temperature of 10-50°C and a humidity of 20-80%, immerse the dry base membrane in the aqueous phase solution for 0.5-20 min to allow the base membrane to fully adsorb the aqueous phase solution, and the polyamine in the aqueous phase solution reacts with the chloromethyl groups on the surface of the base membrane; take out the base membrane, drain it in the air until the excess aqueous phase solution on the membrane surface is removed; place it in the organic phase solution for interfacial polymerization reaction, polymerize at 10-80°C for 5-200 s, then take it out and drain it in the air to obtain a nascent composite membrane; post-treat the nascent composite membrane at 20-120°C for 0-60 min to obtain a composite reverse osmosis membrane based on the polyarylethersulfone base membrane containing a phthalazinone structure.

3. According to the preparation method described in claim 2, characterized in that, The blend ultrafiltration membrane of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure is prepared by solution blending of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure using the phase inversion method, wherein the mass ratio of chloromethylated polyarylethersulfone to polyarylethersulfone containing a phthalazinone structure is 1:1-1:

50.

4. According to the preparation method described in claim 3, characterized in that, 1) Add an additive and a solvent to chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure, mix and stir until completely dissolved to obtain a homogeneous and stable casting solution; among them, the total mass of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure accounts for 5-30% of the mass fraction of the casting solution, the additive accounts for 0-30% of the mass fraction of the casting solution, and the solvent accounts for 40-95% of the mass fraction of the casting solution; 2) Scrape the film under the conditions of an environmental temperature of 10-50°C and a humidity of 20-80%; after the solvent in the casting solution evaporates for 0-5 min, place it in a gel bath at 0-50°C, and the additive in the gel bath accounts for 0-10 wt%, gel into an ultrafiltration membrane, and soak it in water to wash away the solvent and additive to obtain the blend ultrafiltration membrane of chloromethylated polyarylethersulfone and polyarylethersulfone containing a phthalazinone structure.

5. According to the preparation method described in claim 4, characterized in that, The additive is one or more of ethylene glycol methyl ether, ethanol, ethylene glycol, glycerol, polyethylene glycol, and polyvinylpyrrolidone; The solvent described above is one or a mixture of two or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and dimethyl sulfoxide; The additive in the coagulation bath described above is one or a mixture of two or more of inorganic salts, organic solvents, acids, and bases; The inorganic salt is NaCl, LiCl, or CaCl2; the organic solvent is ethanol or isopropanol; the acid is HCl; the base is NaOH.

6. The preparation method according to any one of claims 1-5, characterized in that The polyamine is one or a mixture of two or more of m-phenylenediamine, p-phenylenediamine, biphenylenediamine (such as 4,4'-diaminobiphenyl), and melamine.

7. The preparation method according to any one of claims 1-5, characterized in that The aqueous phase additive is one or a mixture of two or more of triethylamine, sodium carbonate, sodium dodecyl sulfate, Tween-80, and camphorsulfonic acid.

8. The preparation method according to any one of claims 1-5, characterized in that The acyl chloride monomer is one or a mixture of two or more of isophthaloyl chloride, terephthaloyl chloride, trimellitic trichloride, and pyromellitic tetrachloride.

9. The preparation method according to any one of claims 1-5, characterized in that The alkane organic solvent is one or a mixture of two or more of n-hexane, cyclohexane, n-heptane, n-decane, and isoparaffin.

Images