CN114656356B - Spiro biindane tetraacyl chloride and preparation method thereof, and composite membrane and preparation method thereof - Google Patents

Abstract

The invention provides spiro biindane tetraacyl chloride which has a structure shown in a formula I. The spiro biindane tetraacyl chloride provided by the invention has a three-dimensional torsion structure, and the generated polymer has self-contained micropore characteristics and can show higher permeability when used for separation membrane materials.

Description

A kind of spirocyclic diindanetetrayl chloride and its preparation method, composite membrane and its preparation method

Technical field

The invention relates to the technical field of synthetic chemistry, and in particular to a spirocyclic diindanetetrayl chloride and its preparation method, a composite membrane and its preparation method.

Background technique

Polycarboxylic acid chlorides are important chemical raw materials. They are mainly used to prepare polyamide, polyester, polyimide and other materials or films. They are widely used in the fields of separation and adsorption, such as gas separation membranes, organic solvent nanofiltration membranes, and microporous adsorption media. wait.

The synthesis method of the polybasic acid chloride monomer is to react the polycarboxylic acid with an acylating reagent to obtain the acid chloride monomer. The selected acylating reagent is one or more of sulfoxide dichloride, oxalyl chloride, triphosgene and phosphorus pentachloride. In 2005, Zhou Yong and others used triphosgene to synthesize acyl chloride monomers such as 5-oxyformyl chloride-isopeptide acyl chloride (CFIC) and 5-isocyanatoisopeptide acyl chloride (ICIC) (for example, Desalination, 2005, 180, 189-196; Journal of Membrane Science, 2006, 270, 162-168; Desalination, 2006, 192, 182-189). In 2009, Li Lei prepared a variety of polybasic acid chlorides containing biphenyl structures through Suzuki coupling, Ni(0) catalytic coupling and sulfoxide chloride: 3,4,5-biphenyltriacyl chloride, 3,3 ′,5,5′-biphenyl tetrayl chloride, 2,2′,5,5′-biphenyl tetrayl chloride, 2,2′,4,4′-biphenyl tetrayl chloride (for example, Journal of Membrane Science, 2007, 289(1/2):258-267; Journal of Membrane Science, 2008, 315(1-2):20-27; Journal of Membrane Science, 2009, 335(1-2):133-139). In 2013, Wang Tunyu synthesized 2,4,4′,6-biphenyltetrayl chloride, 2,3′,4,5′,6-biphenylpentayl chloride and 2,2′,4,4′,6 , 6′-biphenyl hexayl chloride (such as the literature Journal of Membrane Science, 2013, 440: 48-57).

However, the polymers produced by existing polybasic acid chlorides (such as trimesoyl chloride and diphenyltetrayl chloride) do not have microporous characteristics. Their molecular chains are effectively stacked and their free volumes are small. The densely packed structure of the polymer membrane hinders Gases and organic solvents pass through.

Contents of the invention

In view of this, the technical problem to be solved by the present invention is to provide a spirocyclodiindanetetrayl chloride and its preparation method, a composite membrane and its preparation method. The prepared spirocyclodiindanetetrayl chloride can be used as a separation membrane material, which can improve Permeability of separation membrane.

The invention provides a spirocyclic diindanetetrayl chloride, which has the structure shown in formula I:

Wherein, R is H, CH ₃ -, CH ₃ CH ₂ - or CH ₃ (CH ₂ ) _n CH ₂ -;

n is an integer from 1 to 20.

Preferably, the spirocyclic diindanetetrayl chloride has the structure shown in formula I-a:

Wherein, R is H, CH ₃ -, CH ₃ CH ₂ - or CH ₃ (CH ₂ ) _n CH ₂ -;

n is an integer from 1 to 20.

Further preferably, the R is CH ₃ -.

The invention discloses a preparation method of the above-mentioned spirobiindanetetrayl chloride, which includes the following steps:

A) Using benzene or dialkylbenzene as raw material, and using metal halide as catalyst, conduct a condensation reaction with 2-halogenated propene to obtain the intermediate shown in formula 1;

B) Using an oxidant to carry out an oxidation reaction on the intermediate shown in Formula 1 to obtain the intermediate shown in Formula 2;

C) Acylation reaction is performed on the carboxyl group of the intermediate shown in formula 2 to obtain the spirocyclic diindanetetrayl chloride shown in formula I;

Preferably, the metal halide is a metal chloride, bromide or iodide. Further preferably, the metal halide is aluminum bromide.

Preferably, the 2-halogenated propene is selected from one or more of 2-iodopropene, 2-bromopropene, and 2-chloropropene.

Preferably, the temperature of the condensation reaction in step A) is 25-60°C, and the reaction time is 48h-72h.

Preferably, after the reaction in step A) is completed, the system is quenched with ice water, and the organic phase is extracted with diethyl ether. After drying, the crude product is obtained by distillation under reduced pressure. Preferably, the crude product is purified, preferably using acetone for recrystallization to obtain the pure intermediate product shown in Formula 1.

Preferably, the oxidizing agent in step B) is potassium permanganate or hydrogen peroxide. The solvent for the oxidation reaction is preferably pyridine. The temperature of the oxidation reaction is preferably 80-140°C, and the reaction time is preferably 48h-72h. Preferably, after the reaction is completed, manganese dioxide is removed by hot filtration, the pH of the filtrate is adjusted to 1 with concentrated hydrochloric acid, and a white solid is precipitated by cooling, which is the pure intermediate product shown in Formula 2.

Preferably, the acylating reagent used for the acylation reaction in step C) is sulfoxide chloride, triphosgene, phosphorus pentachloride or oxalyl chloride.

Preferably, the acylation reaction in step C) may use sulfoxide chloride as the acylating reagent. Specifically, the intermediate spirobiindanetetracarboxylic acid and thionyl chloride shown in Formula 2 are mixed and reacted. The molar ratio of spirobiindanetetracarboxylic acid and thionyl chloride is preferably 1:1 to 20. More preferably, it is 1:1~14, most preferably 1:8, the reaction temperature is preferably 40~150℃, more preferably 60~120℃, most preferably 80~100℃, the reaction time is preferably 2~24 hours , more preferably 3 to 12 hours, most preferably 4 to 8 hours. After the reaction in the present invention, it is preferable to include purification steps such as vacuum distillation and filtration. The present invention does not impose any special restrictions on this. Those skilled in the art can select and adjust according to the actual situation and product requirements.

The reaction equation is as follows:

Preferred in the present invention, step C) can also adopt the triphosgene method. Specifically, under nitrogen protection, triphosgene and a solvent are added to the reaction vessel, and the spirobiindane shown in formula 2 is slowly added to the tetracarboxylic acid under an ice bath. The acid is dropped into the bottle, and an appropriate amount of catalyst is preferably slowly added. After the dripping is completed, react in an ice bath for 1 to 3 hours, then raise the temperature to 30 to 50°C to react for a period of time, let it stand for filtration, and recover the solvent to obtain the spirobiindanetetrayl chloride product.

The reaction equation is as follows:

Preferred in the present invention, the step C) can also adopt the phosphorus pentachloride method. Specifically, an equal amount of phosphorus pentachloride and sodium spirobiindane tetracarboxylate shown in Formula 2 are placed in a 500mL single-necked flask; Condensation and reflux reaction at 170~180°C for 12~15h; cool, add 1~1.5L water and 1~1.5kg crushed ice, wash once with water after separation, extract with ether, and rotary evaporate under reduced pressure to remove the ether to obtain the product spiroindene Full of acid chloride.

The reaction equation is as follows:

Preferred in the present invention, the step C) can also adopt the oxalyl chloride method. Specifically, diethyl ether is used as the solvent, a trace amount of DMF is used as the catalyst, and the spirobiindane tetracarboxylic acid shown in Formula 2 is placed in a three-necked bottle at room temperature. Stir at high temperature, add excess oxalyl chloride dropwise, continue the reaction for 24 hours after the dropwise addition, recover ether and oxalyl chloride under normal pressure, and obtain the product spirobiindanetetrayl chloride.

The reaction equation is as follows:

The present invention can also use spirobiindantetraphenol as raw material. Specifically, spirobiindantetraphenol is used as raw material, and the phenolic hydroxyl group is protected by trifluoromethanesulfonic anhydride (Tf ₂ O), and then ferrocene is used to protect the phenolic hydroxyl group. Under the action of palladium dichloride complex catalyst (Pd ₂ (dba) ₃ /dppf), it reacts with zinc cyanide (Zn(CN) ₂ ) to produce the corresponding spirocyclic diindane tetracyano compound, cyanide. After hydrolysis of the base, a carboxyl group can be generated, and the spirobiindanetetracarboxylic acid chloride is synthesized by reacting the spirobiindanetetracarboxylic acid compound with sulfoxide chloride (SOCl ₂ ). Or prepare spirobiindanetetrayl chloride by any of the above methods (triphosgene method, phosphorus pentachloride method, oxalyl chloride method).

The equation for the above reaction is as follows:

The spirocyclic diindanetetrayl chloride prepared by the present invention has a three-dimensional twisted structure, and the generated polymer has its own microporous characteristics, and will exhibit higher permeability when used as a separation membrane material.

The invention also provides a high-flux nanofiltration composite membrane, which includes a support layer and a polyamide active separation layer and/or a polyimide active separation layer compounded on the surface of the support layer;

The polyamide active separation layer is obtained by interfacial polymerization of the above-mentioned spirocyclodiindanetetrayl chloride or the spirocyclodiindanetetrayl chloride prepared by the above preparation method and m-phenylenediamine monomer;

The polyimide active separation layer is obtained by imidization treatment of the above polyamide active separation layer.

The present invention has no special limitation on the support layer. It can be a nanofiltration composite membrane support layer well known to those skilled in the art. In the present invention, the support layer is preferably a polyether ether ketone support layer.

Preferably, the thickness of the support layer is 50 μm.

Preferably, the thickness of the polyamide active separation layer and/or the polyimide active separation layer is 80 to 100 nm.

The invention provides a preparation method for the above-mentioned high-flux nanofiltration composite membrane, which includes the following steps:

S1) Cover the surface of the support layer film with an aqueous solution of m-phenylenediamine monomer, then remove excess aqueous solution of m-phenylenediamine monomer and dry it to obtain a composite membrane;

S2) Cover the surface of the above-mentioned composite membrane with the organic solution of the above-mentioned spirobiindantetrayl chloride or the spirocyclodiindanetetrayl chloride monomer prepared by the above-mentioned preparation method, perform interfacial polymerization, and then perform heat treatment to obtain a polyamide composite membrane;

S3) The above-mentioned polyamide composite membrane is subjected to imidization treatment to obtain a high-flux nanofiltration composite membrane.

The high-flux nanofiltration composite membrane of the present invention is a polyimide nanofiltration composite membrane with high-flux performance.

The mass volume concentration of the aqueous solution of m-phenylenediamine monomer is preferably 0.1% to 8%, more preferably 0.5% to 6%, most preferably 1% to 4%; the covering time is preferably 1 min to 8 min , more preferably 2 min ~ 6 min, most preferably 4 min ~ 5 min. The present invention has no special restrictions on the coverage. It can be defined by the coverage well known to those skilled in the art. It can be full coverage or partial coverage of the surface of the film. It can be used Pour, soak, smear or spray. The present invention also removes excess aqueous solution of m-phenylenediamine monomer on the surface and air-dries. The drying time is preferably 5 min to 10 min, more preferably 6 min to 9 min, and most preferably 7 min to 8 min.

The mass volume concentration of the organic solution of the spirobiindantetrayl chloride monomer is preferably 0.05% to 4%, more preferably 0.1% to 2%, most preferably 0.2% to 1%, and the covering time is preferably It is 20s to 10min, more preferably 1min to 8min, and most preferably 2min to 5min. The present invention has no special restrictions on the solvent of the organic solution. It can be a solvent used for mixing acid chloride monomers that is well known to those skilled in the art. The present invention is preferably an Isopar G/o-xylene mixed solution. The mixing ratio is not limited and can be adjusted by those skilled in the art according to actual conditions.

The temperature of the heat treatment in the present invention is preferably 75°C to 110°C, more preferably 80°C to 100°C, and most preferably 85°C to 95°C. The present invention has no special restrictions on other conditions of the heat treatment. According to the technology in the art The conditions for heat treatment of composite membranes that are familiar to personnel are sufficient.

The method of imidization in the present invention is not particularly limited, and can be an imidization method well known to those skilled in the art.

The imidization method is divided into thermal imidization method and chemical imidization method. Thermal imide method is to program the temperature of the film sample to 300°C in a nitrogen atmosphere and keep it for 2 hours. When preparing polyimide composite membranes by the chemical imide method, the polyamide membrane must be soaked in an appropriate amount of dehydrating agent and catalyst solution. The dehydrating agent is acetic anhydride, propionic anhydride, butyric anhydride, trifluoroacetic anhydride, benzoic anhydride, 1,3-dichlorohexylcarbodiimide, N,N-dicyclohexylcarbodiimide, lower aliphatic halogenated Any one or combination of substances, halogenated lower aliphatic halides, halogenated lower aliphatic anhydrides, arylsulfonic acid dihalides, thionyl halides and phosphorus halides. The imidization catalyst can be selected from one or more of heterocyclic tertiary amines, aliphatic tertiary amines, and aromatic tertiary amines; the heterocyclic tertiary amine is preferably one of quinoline, isoquinoline, pyridine, etc. One or more kinds; the aliphatic tertiary amine is preferably one or more of 1,3-dichlorohexylcarbodiimide, triethylamine, etc.; the aromatic tertiary amine is preferably N, N-di Methylaniline etc. The above-mentioned dehydrating agent and catalyst can be used alone or in mixture.

The present invention preferably adopts the chemical imidization method. Specifically, a dehydrating agent and a catalyst are used to prepare an imidization solution, and then the nascent composite nanofiltration membrane is immersed in the imidization solution. After the imidization is completed, , obtaining a solvent-resistant composite nanofiltration membrane.

The follow-up step of the present invention preferably also includes steps such as cleaning. The present invention is not particularly limited to this. Cleaning methods well known to those skilled in the art can be used. In the present invention, it is preferred to use a cleaning method of 25°C to 80°C, and more preferably 30°C to 65°C. Wash several times with ionized water, and the finally obtained nanofiltration composite membrane is stored in deionized water for later use.

Compared with the prior art, the present invention provides a spirocyclic diindanetetrayl chloride having the structure shown in Formula I. The above-mentioned spirocyclic diindanetetrayl chloride provided by the present invention has a three-dimensional three-dimensional twisted structure, and the generated polymer has its own microporous characteristics, and will exhibit higher permeability when used as a separation membrane material.

Description of the drawings

Figure 1 is the infrared spectrum of the monomer prepared in Example 1;

Figure 2 is a hydrogen nuclear magnetic spectrum of the spirobiindanetetrayl chloride (product 3) prepared in Example 1.

Detailed ways

In order to further illustrate the present invention, the spirocyclic diindanetetrayl chloride and its preparation method, the composite membrane and its preparation method provided by the present invention will be described in detail below in conjunction with the examples.

Pure solvent flux: The volume of pure solvent passing through unit membrane area per unit time at a specific pressure. It can be expressed by the following formula:

(V(L)-volume of permeated solvent, A(m ² )-effective area of membrane, t(h)-time, P(bar)-pressure)

In the following examples, the pure solvent flux test conditions are as follows: operating temperature 25°C, 50 ppm methanol dye solution, and operating pressure 10 bar. The permeation flux of a nanofiltration membrane is expressed as the pure solvent flux at that pressure. Before testing the permeation flux of the nanofiltration membrane, the composite membrane was prepressed at 10 bar for 8 hours to ensure the stability of the test data. The composite membrane of each formula was tested with 6 data and the average value was taken.

Example 1

3,3,3',3'-Tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobisindane

The synthesis method includes the following steps:

(1) Add o-xylene (40 ml) and aluminum bromide (6.7 mmol, 1.8 g) into a three-necked flask, and stir to dissolve. 2-bromopropene (25.7mmol, 3.1g) was added dropwise, and the reaction was carried out at 60°C for 72 hours. After the reaction was completed, the reaction was quenched with ice water, and the organic phase was extracted with diethyl ether, dried, and distilled under reduced pressure to obtain the crude product as brown powder. The crude product was recrystallized from acetone to obtain colorless crystal 1, with a yield of 31.4%.

(2) Add 1 (3mmol, 1g), pyridine (27.17ml), and purified water (25ml) to the three-necked flask. Stir to dissolve, reflux at 80-90°C for two hours, add potassium permanganate (10g) in batches, raise the temperature to boiling, and react for 24 hours. Manganese dioxide was removed by hot filtration, and the pH of the filtrate was adjusted to 1 with concentrated hydrochloric acid. After cooling, a white solid 2 precipitated. After drying, it weighed 1.3g, with a yield of 93%.

(3) Mix 2 and thionyl chloride (10 ml) and react. The reaction temperature is 80°C and the time is 3 hours. After the reaction is completed, the temperature is cooled to 25°C. Most of the thionyl chloride is removed under normal pressure and the pressure is reduced. The remaining thionyl chloride was removed by distillation, and 3 was obtained by recrystallization from o-xylene. The yield of the obtained product was 90% and the purity was 95%.

The obtained target product was subjected to infrared spectrum and hydrogen nuclear magnetic spectrum detection, and the results are shown in Figures 1 to 2. Figure 1 is the infrared spectrum of the monomer prepared in Example 1 of the present invention. It can be seen from Figure 1 that product 2 is 3,3,3',3'-tetramethyl-5,5',6,6'-tetracarboxy-1,1'-spirobiindane, and product 3 is obtained The target product is 3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobisindane. Figure 2 shows the hydrogen nuclear magnetic spectrum of 3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobisindane.

Example 2

3,3,3',3'-Tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobisindane

Compound 2 prepared in Example 1 and thionyl chloride (15 ml) were mixed and reacted, a drop of DMF was added dropwise, the reaction temperature was 100°C, the time was 1 hour; after the reaction was completed, the temperature was cooled to 25°C, and the large amount of DMF was removed under normal pressure. Part of the sulfoxide dichloride was distilled under reduced pressure to remove the residual sulfoxide chloride, and recrystallized from o-xylene to obtain 3. The yield of the obtained product was 92% and the purity was 96%.

Example 3

3,3,3’,3’-Tetramethyl-5,5’,6,6’-tetrachloroformyl-1,1’-spirobisindane

Compound 2 prepared in Example 1 and thionyl chloride (20 ml) were mixed and reacted, a drop of DMF was added dropwise, the reaction temperature was 60°C, the time was 6 hours; after the reaction was completed, the temperature was cooled to 25°C, and the large amount of DMF was removed under normal pressure. Part of the sulfoxide dichloride was distilled under reduced pressure to remove the residual sulfoxide chloride, and recrystallized from o-xylene to obtain 3. The yield of the obtained product was 87% and the purity was 95%.

Example 4

Description of the process of preparing an interfacial polymerized film by reacting the acid chloride monomer prepared in Example 1 with m-phenylenediamine

Pour an aqueous solution of m-phenylenediamine with a mass volume concentration (g/ml) of 2% on the surface of the polyetheretherketone support layer film and keep it for 4 minutes. Then pour away the excess m-phenylenediamine solution on the surface of the support membrane, wipe off the obvious water droplets on the membrane surface with filter paper, and dry it in the air for 7 minutes. Then, 3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobis with a mass volume concentration (g/ml) of 0.1% was added. Indan's Isopar G/o-xylene solution was poured onto the membrane surface for interfacial polymerization, where Isopar G/o-xylene = 1, and the reaction time was 5 minutes. Finally, the prepared composite membrane was placed in a blast oven at 90°C for 6 minutes. Soak the prepared polyamide composite membrane in a mixed solvent of an appropriate amount of acetic anhydride, 1,3-dichlorohexylcarbodiimide and triethylamine for 2 hours to obtain a polyimide composite membrane, rinse it with ethanol and water, and set it aside.

Example 5

3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobiindan prepared in Example 1 and m-phenylenediamine Reaction to prepare nanofiltration membrane. The mass concentration (g/ml) of spirobiindanetetrayl chloride monomer is 0.2%. The preparation conditions of other membranes were the same as in Example 4.

Example 6

3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobiindan prepared in Example 1 and m-phenylenediamine Reaction to prepare nanofiltration membrane. The mass concentration (g/ml) of spirobiindanetetrayl chloride monomer is 0.3%. The preparation conditions of other membranes were the same as in Example 4.

Example 7

3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobiindan prepared in Example 1 and m-phenylenediamine Reaction to prepare nanofiltration membrane. The mass concentration (g/ml) of spirobiindanetetrayl chloride monomer is 0.4%. The preparation conditions of other membranes were the same as in Example 4.

Example 8

3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobiindan prepared in Example 1 and m-phenylenediamine Reaction to prepare nanofiltration membrane. The mass concentration (g/ml) of spirobiindanetetrayl chloride monomer is 0.5%. The preparation conditions of other membranes were the same as in Example 4.

Example 9

3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobiindan prepared in Example 1 and m-phenylenediamine Reaction to prepare nanofiltration membrane. The mass concentration (g/ml) of spirobiindanetetrayl chloride monomer is 0.6%. The preparation conditions of other membranes were the same as in Example 4.

Example 10

3,3,3',3'-tetramethyl-5,5',6,6'-tetrachloroformyl-1,1'-spirobiindan prepared in Example 1 and m-phenylenediamine Reaction to prepare nanofiltration membrane. The mass concentration (g/ml) of spirobiindanetetrayl chloride monomer is 0.8%. The preparation conditions of other membranes were the same as in Example 4.

Comparative example 1

Pour an aqueous solution of m-phenylenediamine with a mass volume concentration (g/ml) of 2% on the surface of the polyetheretherketone support layer film and keep it for 4 minutes. Then pour away the excess m-phenylenediamine solution on the surface of the support membrane, wipe off the obvious water droplets on the membrane surface with filter paper, and dry it in the air for 7 minutes. Then, an Isopar G solution of trimesoyl chloride with a mass volume concentration (g/ml) of 1% was poured onto the membrane surface for interfacial polymerization, and the reaction time was 40 s. Finally, the prepared composite membrane was placed in a blast oven at 90°C for 5 minutes. Wash several times with deionized water at 40°C and store in deionized water for later use.

The following reaction formula 2 is the structure of the polyamide produced by the reaction of spirocyclodiindanetetrayl chloride and m-phenylenediamine. Reaction formula 1 is the molecular structure of the polyamide produced by the reaction of trimesoyl chloride and m-phenylenediamine. It can be seen that , compared with the structure of traditional polyamide (PA/TMC), PA/TAC-TSBI and PI/TAC-TSBI have large spatial distortion, strong rigidity, large free volume, and microporous characteristics.

1.

2.

The permeability performance of the nanofiltration membranes prepared in Examples 4 to 10 and Comparative Example 1 was tested, and the results are shown in Table 1:

Table 1 Organic solvent permeability properties of polyamide membranes and polyimide membranes prepared based on the interfacial polymerization of spirobiindantetrayl chloride and m-phenylenediamine

The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of the claims of the present invention.

Claims (4)

1. A high-flux nanofiltration composite membrane comprises a support layer and a polyamide active separation layer and/or a polyimide active separation layer which are compounded on the surface of the support layer;

the polyamide active separation layer is prepared by interfacial polymerization of spiro biindane tetraoyl chloride with a structure shown in a formula I-a and m-phenylenediamine monomers;

the polyimide active separation layer is obtained by imidizing the polyamide active separation layer;

wherein R is CH ₃ -；

The preparation method of the high-flux nanofiltration composite membrane comprises the following steps:

s1) covering the surface of a support layer film with an aqueous solution of m-phenylenediamine monomer, removing the excessive aqueous solution of m-phenylenediamine monomer, and airing to obtain a composite film;

s2) covering an organic solution of a spiro biindane tetraacyl chloride monomer on the surface of the composite membrane, performing interfacial polymerization, and then performing heat treatment to obtain a polyamide composite membrane;

s3) carrying out imidization treatment on the polyamide composite membrane to obtain a high-flux nanofiltration composite membrane;

the concentration of the aqueous solution of the m-phenylenediamine monomer is 2%g/mL;

the concentration of the organic solution of the spirocyclic biindane tetraacyl chloride monomer is 0.1% or 0.2% g/mL.

2. The high flux nanofiltration composite membrane of claim 1, wherein the support layer is a polyetheretherketone support layer.

3. The method for preparing the high-flux nanofiltration composite membrane according to any one of claims 1 to 2, comprising the following steps:

s1) covering the surface of a support layer film with an aqueous solution of m-phenylenediamine monomer, removing the excessive aqueous solution of m-phenylenediamine monomer, and airing to obtain a composite film;

s2) covering an organic solution of a spiro biindane tetraacyl chloride monomer on the surface of the composite membrane, performing interfacial polymerization, and then performing heat treatment to obtain a polyamide composite membrane;

s3) carrying out imidization treatment on the polyamide composite membrane to obtain a high-flux nanofiltration composite membrane;

the concentration of the aqueous solution of the m-phenylenediamine monomer is 2%g/mL;

the concentration of the organic solution of the spirocyclic biindane tetraacyl chloride monomer is 0.1% or 0.2% g/mL.

4. A process according to claim 3, wherein the organic solvent in the organic solution of the spirocyclic biindane tetraacyl chloride monomer is Isopar G/o-xylene mixed solution;

the temperature of the heat treatment is 75-110 ℃.