CN116987266A

CN116987266A - Polyimide resin, gas separation membrane and preparation method thereof

Info

Publication number: CN116987266A
Application number: CN202311035571.4A
Authority: CN
Inventors: 宋佃凤; 覃诗琪; 吴立群; 郁国强; 汤秀秀; 徐丽丽
Original assignee: Shandong Renfeng Speical Materials Co ltd; Shanghai Carbon Dynamic New Energy Technology Co ltd
Current assignee: Shandong Renfeng Speical Materials Co ltd; Shanghai Carbon Dynamic New Energy Technology Co ltd
Priority date: 2023-08-16
Filing date: 2023-08-16
Publication date: 2023-11-03

Abstract

The invention discloses polyimide resin, a gas separation membrane and a preparation method thereof, and relates to the technical field of gas separation membranes, so as to solve the problems of aging resistance and poor plasticizing resistance of the gas separation membrane. The polyimide resin is prepared from diamine monomer and a triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride structure, and the molecular chain of the polyimide resin contains the triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride structure. The gas separation membrane is composed of polyimide resin. The polyimide resin provided by the disclosure is used for preparing a gas separation membrane.

Description

Polyimide resin, gas separation membrane and preparation method thereof

Technical Field

The disclosure relates to the technical field of gas separation membranes, in particular to polyimide resin, a gas separation membrane and a preparation method thereof.

Background

Hydrogen energy is an alternative energy source to fossil fuels in the global energy conversion development, and the separation and production demands of hydrogen in various countries are increasing. However, the common centralized hydrogen production method has byproducts, so that hydrogen cannot be directly used and needs to be separated from the byproducts, and the gas separation membrane has the advantages of no secondary pollution, simple device and the like, and is attracting more and more attention.

However, the polyimide gas separation membrane commonly used in the membrane materials of the gas separation membrane has the problems of easy aging and easy plasticization, and the service life of the membrane is greatly reduced.

Disclosure of Invention

The invention aims to provide polyimide resin, a gas separation membrane and a preparation method thereof, which are used for providing a gas separation membrane material and a gas separation membrane with good ageing resistance, plasticizing resistance, solvent resistance and permeability and good selectivity.

In order to achieve the above object, the present disclosure provides the following technical solutions:

a polyimide resin having the structural formula:

wherein n is a natural number of 1 or more, R ₁ Is an aromatic diamine residue;

the molecular chain of the polyimide resin contains a triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride structure.

Compared with the prior art, in the polyimide resin provided by the disclosure, the structural formula of the polyimide resin can be used for determining that the polyimide resin has a three-dimensional rigid structure, so that the internal molecular cavity of the polyimide resin is stable, and the polyimide resin is good in solvent resistance, ageing resistance and plasticizing resistance. Because the three-dimensional network structure with high interconnection can be formed among the plurality of three-dimensional rigid structures through interconnection covalent bonds, when the polyimide resin is used for preparing the gas separation membrane, the three-dimensional network structure can be formed among molecular chains of the polyimide resin, and the three-dimensional network structure with high interconnection limits the shrinkage, expansion and movement of the molecular chains, so that the polyimide resin has better solvent resistance, ageing resistance and plasticizing resistance. Meanwhile, the highly-interconnected three-dimensional net structure also has a supporting function, so that a molecular cavity in the gas separation membrane is in a stable state, tight accumulation of molecular chains in the gas separation membrane is avoided, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is used as a crosslinking center, the distance between the molecular chains is relatively fixed, and the selectivity and the permeability of the gas separation membrane are improved.

The present disclosure also provides a gas separation membrane composed of the polyimide resin described above.

Compared with the prior art, the beneficial effects of the gas separation membrane provided by the present disclosure are the same as those of the polyimide resin according to the above technical scheme, and the description thereof is omitted here.

The present disclosure also provides a method for preparing a gas separation membrane, for preparing the gas separation membrane, the method comprising:

under the first reaction condition, adding triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride into a mixed solution of a first organic solvent and a diamine monomer to obtain a spinning solution;

mixing a second organic solvent with water to obtain a core liquid;

under a second reaction condition, mixing and extruding the spinning solution and the core solution into a coagulating bath for spinning to obtain a prefabricated gas separation membrane;

and washing and drying the prefabricated gas separation membrane to obtain the gas separation membrane.

Compared with the prior art, the preparation method of the gas separation membrane has the advantages that the preparation method of the gas separation membrane has the same beneficial effects as the polyimide resin in the technical scheme, and the description is omitted here.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate and explain the present disclosure, and together with the description serve to explain the present disclosure. In the drawings:

Fig. 1 shows a schematic flowchart of a preparation method of a polyimide resin provided according to an exemplary embodiment of the present disclosure;

FIG. 2 shows a schematic flow diagram one of a method of preparing a gas separation membrane according to an exemplary embodiment of the present disclosure;

FIG. 3 shows a schematic flow chart II of a method of preparing a gas separation membrane provided in accordance with an exemplary embodiment of the present disclosure;

fig. 4 shows a schematic flowchart three of a method of manufacturing a gas separation membrane provided according to an exemplary embodiment of the present disclosure.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood that the description is only exemplary and is not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the concepts of the present disclosure.

Various structural schematic diagrams according to embodiments of the present disclosure are shown in the drawings. The figures are not drawn to scale, wherein certain details are exaggerated for clarity of presentation and may have been omitted. The shapes of the various regions, layers and relative sizes, positional relationships between them shown in the drawings are merely exemplary, may in practice deviate due to manufacturing tolerances or technical limitations, and one skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions as actually required.

In the context of the present disclosure, when a layer/element is referred to as being "on" another layer/element, it can be directly on the other layer/element or intervening layers/elements may be present therebetween. In addition, if one layer/element is located "on" another layer/element in one orientation, that layer/element may be located "under" the other layer/element when the orientation is turned. In order to make the technical problems, technical solutions and advantageous effects to be solved by the present disclosure more clear, the present disclosure is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present disclosure and are not intended to limit the present disclosure.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present disclosure, the meaning of "a plurality" is two or more, unless explicitly defined otherwise. The meaning of "a number" is one or more than one unless specifically defined otherwise.

In the description of the present disclosure, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the terms in this disclosure will be understood by those of ordinary skill in the art as the case may be.

Hydrogen energy is the highest energy source in energy content per unit weight among known fuels, the hydrogen energy storage is rich, the only byproduct of the energy source is water, the hydrogen energy is gradually becoming an alternative energy source of fossil fuels in global energy transformation development, and the separation and production demands of hydrogen in various countries are always increasing.

The hydrogen can be produced by various processes, and more common preparation methods are coal hydrogen production, methane steam reforming hydrogen production and industrial byproduct gas hydrogen production. The tail gas of the hydrogen production methods contains byproducts, and the hydrogen cannot be directly used, for example, the tail gas of the coal hydrogen production mainly contains N ₂ ，CO，CO ₂ ，CH ₄ The tail gas of methane steam reforming hydrogen production mainly contains CH ₄ 、CO、CO ₂ . The industrial by-product gas for preparing hydrogen mainly comprises chlor-alkali industrial by-product gas, coal chemical coke oven gas, light hydrocarbon cracking by-product hydrogen, synthetic ammonia, methanol purge gas and the like, and the coal chemical coke oven gas needs H ₂ From CH ₄ 、CO、C ₂ The unsaturated hydrocarbon and CO ₂ 、N ₂ H is needed to be separated from the purge gas of the synthetic amine and the methanol ₂ From N ₂ And Ar and other inert gases.

Compared with pressure swing adsorption and cryogenic separation, the membrane separation device is simple, low in energy consumption and low in investment, phase change is not involved in the separation process, secondary pollution is avoided, and the method is an efficient and simple gas separation method and is receiving more and more attention.

Among membrane materials of the gas separation membrane, the polymer membrane is the material with highest commercial value due to easy production, adjustable structure and relatively low cost. Aromatic polyimide is a main stream material of a current gas separation membrane due to its excellent heat resistance and solvent resistance. However, the aromatic polyimide gas separation membrane has the problems of easy aging and easy plasticization, and the service life of the membrane is greatly reduced.

In order to overcome the problems, the exemplary embodiments of the present disclosure provide a polyimide resin, which has a stable internal molecular cavity due to the presence of a triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride structure in a molecular chain, so that the polyimide resin has good solvent resistance, aging resistance and plasticizing resistance. When the polyimide resin is used for preparing the gas separation membrane, a plurality of three-dimensional rigid structures in the polyimide resin can form a highly interconnected three-dimensional network structure through interconnection covalent bonds, so that the polyimide resin has good solvent resistance, ageing resistance and plasticizing resistance.

Exemplary embodiments of the present disclosure provide a polyimide resin having a structural formula:

wherein n is a natural number of 1 or more, R ₁ Is an aromatic diamine residue.

The molecular chain of the polyimide resin contains a triptycene-2,3,6,7,14,15-hexaformic acid dianhydride structure, the polyimide resin is a three-dimensional rigid structure, a plurality of three-dimensional rigid structures can form a highly interconnected three-dimensional network structure through interconnected covalent bonds, and the mobility between molecular chains is reduced, so that when the polyimide resin is used for preparing the gas separation membrane, the plasticizing resistance of the gas separation membrane is better, and meanwhile, the highly interconnected network structure enables the internal molecular cavity glue of the gas separation membrane to be stable, and the aging resistance of the gas separation membrane is improved. Because the three-dimensional rigid structure has supporting property, the molecular chains of the three-dimensional net structure formed by interconnecting a plurality of three-dimensional rigid structures have relatively fixed intervals and cannot be piled up, so that the gas separation membrane has relatively good permeability and selectivity.

From the above, in the polyimide resin provided in the exemplary embodiments of the present disclosure, the structural formula of the polyimide resin may determine that the polyimide resin has a three-dimensional rigid structure, so that the internal molecular cavity of the polyimide resin is stable, and thus the polyimide resin has better solvent resistance, aging resistance and plasticizing resistance. Because the three-dimensional network structure with high interconnection can be formed among the plurality of three-dimensional rigid structures through interconnection covalent bonds, when the polyimide resin is used for preparing the gas separation membrane, the three-dimensional network structure can be formed among molecular chains of the polyimide resin, and the three-dimensional network structure with high interconnection limits the shrinkage, expansion and movement of the molecular chains, so that the polyimide resin has better solvent resistance, ageing resistance and plasticizing resistance. Meanwhile, the highly-interconnected three-dimensional net structure also has a supporting function, so that a molecular cavity in the gas separation membrane is in a stable state, tight accumulation of molecular chains in the gas separation membrane is avoided, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is used as a crosslinking center, the distance between the molecular chains is relatively fixed, and the selectivity and the permeability of the gas separation membrane are improved.

As a possible implementation manner, R is as follows ₁ Any one of the following groups:

exemplary, R ₁ May beCan be +.>Can be +.>Can be +.>Can be +.>Can be +.>Can be +.>Can also be +.>

Fig. 1 shows a schematic flowchart of a preparation method of a polyimide resin provided according to an exemplary embodiment of the present disclosure. As shown in fig. 1, the method for preparing the polyimide resin is used for preparing the polyimide resin, and comprises the following steps:

step 100: at the temperature of-80 ℃ to 10 ℃, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is added into the mixed solution of the organic solvent and the diamine monomer to obtain the polyamic acid solution. The mass fraction of the polyamic acid in the polyamic acid solution is 10% to 40%, for example, the mass fraction of the polyamic acid in the polyamic acid solution may be 10%, may be 20%, may be 40%, or the like, and is not limited thereto. It is to be understood that the reaction temperature may be-80 ℃, may be-50 ℃, may be 10 ℃ and the like, and is not limited thereto. By preparing the polyimide resin at a low temperature, the time for gelation of the polyimide resin can be prolonged, and the yield of the polyimide resin can be improved. It should be noted that in the preparation of polyimide resins, a dry, inert gas-protected environment is required to protect the intermediate polyamic acid from hydrolysis during the preparation of the polyamic acid. The inert gas may be nitrogen or other inert gases.

The organic solvent may be a good solvent for dissolving the polyamic acid. Specifically, the organic solvent may include one or more of N-methylpyrrolidone, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, and N, N-dimethylformamide. The above organic solvent may include, but is not limited to, N-methylpyrrolidone, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, N-dimethylformamide, N-methylpyrrolidone, dimethylacetamide, and the like, by way of example.

Illustratively, the mass ratio of the triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to the diamine monomer is 1: (1-1.5) to ensure that the triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride can react completely. For example, the mass ratio of diamine monomer to triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride may be 1:1. can be 1:1.2, can also be 1:1.5, etc., not limited thereto. The selection of diamine monomer the present disclosure is not limited as long as the diamine monomer that can react with triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is within the selection scope of the present disclosure. Illustratively, the diamine monomer may include one or more of 4,4 '-diaminodiphenyl ether, 2-bis (4-aminophenyl) hexafluoropropane, and 4,4' -diaminobiphenyl. For example, the diamine monomer may be 4,4 '-diaminodiphenyl ether, 2-bis (4-aminophenyl) hexafluoropropane, 4' -diaminobiphenyl, or the like, without being limited thereto.

Step 110: imidizing the polyamic acid solution to obtain polyimide resin. It should be understood that the imidization treatment herein may include a chemical imidization treatment and a thermal imidization treatment. Step 120 is performed when the imidization process is a chemical imidization process, and step 130 is performed when the imidization process is a thermal imidization process.

Step 120: and adding a catalyst and a dehydrating agent into the polyamic acid solution to perform chemical imidization reaction to obtain polyimide resin. The catalyst is used for accelerating the reaction process, and the dehydrating agent is used for removing the moisture in the reaction to obtain the polyimide resin. It is understood that the catalysts herein include one or more of beta-pyrroline, isoquinoline, triethylenediamine, and pyridine. For example, the catalyst may include β -pyrroline, may include isoquinoline, may include triethylenediamine, may include pyridine, may also include triethylenediamine and pyridine, and the like, without being limited thereto. The dehydrating agent may include acetic anhydride.

Step 130: and carrying out thermal imidization treatment on the polyamic acid solution by using a step heating mode to obtain polyimide resin. The reaction can be made more uniform by using a step-wise temperature rising manner so that the polyamic acid can be completely converted into polyimide. It should be noted that the rate of the step heating may be 2 ℃/min to 4 ℃/min, for example, after the temperature is raised to the first temperature at a temperature raising rate of 4 ℃/min, the temperature raising rate may be lowered to 2 ℃/min, so that the temperature raising time between the first temperature and the second temperature may be prolonged, and thus the polyamic acid may be sufficiently converted into polyimide.

The present disclosure also provides a gas separation membrane composed of the above polyimide resin. The gas separation membrane has good aging resistance, plasticizing resistance, solvent resistance, permeability and selectivity.

The above-described gas separation membrane is used to separate hydrogen and nitrogen, hydrogen and carbon monoxide, and hydrogen and methane to obtain hydrogen for storing hydrogen energy. The gas separation membranes have a hydrogen permeability greater than 100barrers, a nitrogen permeability greater than 2.5barrers, a carbon monoxide permeability greater than 2.0barrers, and a methane permeability greater than 2.0barrers.

The exemplary embodiments of the present disclosure also provide a method for preparing a gas separation membrane, for preparing the above-described gas separation membrane. Fig. 2 shows a schematic flowchart one of a method of preparing a gas separation membrane according to an exemplary embodiment of the present disclosure, as shown in fig. 2, the method of preparing a gas separation membrane including:

step 200: under the first reaction condition, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is added into the mixed solution of the first organic solvent and the diamine monomer to obtain spinning solution. It is to be understood that the first reaction conditions herein may include: the reaction temperature is-80℃to 10℃and may be, for example, but not limited to, -80℃and-70℃and 10 ℃. The reaction protecting gas may be an inert gas, for example, nitrogen gas, or another inert gas.

The above-mentioned first organic solvent may include one or more of N-methylpyrrolidone, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide and N, N-dimethylformamide, and it is understood that the first organic solvent herein is the same as that used in the preparation of the polyimide resin, and reference is made thereto for description thereof, which is not exemplified. The diamine monomer may include one or more of 4,4 '-diaminodiphenyl ether, 2-bis (4-aminophenyl) hexafluoropropane and 4,4' -diaminobiphenyl, and it is understood that the diamine monomer herein is the same as the diamine monomer used in the preparation of the polyimide resin, and reference is made thereto for description thereof, which is not exemplified. The mass ratio of the triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to the diamine monomer is 1: (1-1.5), it is to be understood that the mass ratio herein is the same as that in the preparation of the polyimide resin, and reference is made to the description thereof, which is not exemplified.

Step 210: and mixing the second organic solvent with water to obtain a core liquid. It is understood that the second organic solvent herein may include one or more of methanol, ethanol, propanol, and acetone. For example, the second organic solvent may include methanol, may include ethanol, may include propanol, may include acetone, may also include methanol and ethanol, etc., and is not limited thereto. The mass fraction of the second organic solvent in the core liquid is 20% to 80%, for example, the mass fraction of the second organic solvent in the core liquid may be 20%, may be 50%, may be 80%, or the like, and is not limited thereto. The hydrolysis of the polyamic acid solution is reduced by reducing the water fraction in the core solution as much as possible.

Step 220: under the second reaction condition, the spinning solution and the core solution are mixed and extruded into a coagulating bath for spinning, and the prefabricated gas separation membrane is obtained. The core liquid and the spinning liquid are mixed, so that the phase inversion of the skin layer inside the polyamic acid fiber is realized, namely, the phase inversion is realized from the liquid phase to the solid phase, and the polyamic acid fiber is hollow. The hollow fiber membrane is subjected to solvent exchange in a coagulation bath to obtain a prefabricated gas separation membrane.

The second reaction conditions mentioned above include an extrusion speed of the dope of 100ml/h to 300ml/h, for example, the extrusion speed of the dope may be 100ml/h, may be 200ml/h, still 300ml/h, etc., without being limited thereto. The extrusion speed ratio of the spinning solution to the core solution is 1:1-5:1, for example, the extrusion speed ratio of the spinning solution and the core solution may be 1: 1. may be 2: 1. it can also be 5:1, etc., and is not limited thereto. The inner diameter of the polyamic acid hollow fiber can be adjusted by adjusting the extrusion speed of the spinning solution and the extrusion speed of the core solution, when the extrusion speed of the core solution is high, the inner diameter of the polyamic acid hollow fiber is larger, so that the mechanical property of the polyamic acid fiber membrane is poorer, and when the extrusion speed of the core solution is too low, the inner diameter is too small and even a hollow structure cannot be formed, therefore, the extrusion speeds of the spinning solution and the core solution need to be controlled to meet the requirements, so that the polyamic acid fiber membrane with proper aperture is obtained.

The air gap height is 5cm to 20cm, for example, the air gap height may be 5cm, 15cm, 20cm, or the like, and is not limited thereto. Because the solvent can be partially volatilized in the air, the polyamide acid surface skin layer is more compact, and when the air gap height is overlarge, the thickness of the polyamide acid surface skin layer is thicker, so that the permeability of the prepared polyamide acid fiber membrane is reduced, and therefore, in order to improve the permeability of the polyamide acid membrane, the air gap height meets the requirements.

The spinning speed of the spinning is 100m/h to 1000m/h, for example, the spinning speed may be 100m/h, 500m/h, 1000m/h, or the like, and is not limited thereto. Meanwhile, the fiber aperture of the polyamide acid fiber membrane can be adjusted by controlling the wire collecting speed, and the higher the wire collecting speed is, the smaller the aperture is, but the wire collecting speed meets the requirements, so that the phenomenon of wire breakage caused by overlarge wire collecting speed and overlarge traction force on the membrane is avoided.

The temperature of the coagulation bath is 10℃to 50℃and, for example, the temperature of the coagulation bath may be 10℃or 20℃or 50℃and the like, but is not limited thereto. The shape of the fiber holes in the polyamide acid fiber membrane is adjusted by controlling the temperature of the coagulating bath, so that the situation that the strength of the supporting layer is reduced and the service life is shortened due to the fact that the non-solvent and solvent in the coagulating bath are too fast in exchange speed due to the fact that the temperature is too high is prevented, and the shape of the finger fiber holes is formed. The coagulating bath is a mixed solution of a second organic solvent and water, wherein the mass fraction of the second organic solvent in the coagulating bath is 5% -50% so as to prevent the hollow fiber membrane from softening in water. For example, the mass fraction of the second organic solvent in the coagulation bath may be 5%, may be 25%, may be 50%, or the like.

Step 230: and washing and drying the prefabricated gas separation membrane to obtain the gas separation membrane. The polyamic acid fiber film is prepared into a polyimide fiber film by washing to remove residual organic solvent and water in the polyamic acid fiber film, and then by thermal imidization treatment.

As one possible implementation, fig. 3 shows a schematic flowchart two of a method for preparing a gas separation membrane according to an exemplary embodiment of the present disclosure. As shown in fig. 3, the above-mentioned method for obtaining a gas separation membrane by adding triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to a mixed solution of a first organic solvent and a diamine monomer under a first reaction condition may include:

step 300: under the first reaction condition, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is added to a mixed solution of a first organic solvent and a diamine monomer to obtain a polyamic acid solution, wherein the mass fraction of polyamic acid in the polyamic acid solution is 10% -40%, for example, the mass fraction of polyamic acid in the polyamic acid solution may be 10%, 20%, 40% or the like, and the method is not limited thereto. So as to ensure that the polyimide gas separation membrane prepared by the polyamic acid solution has better film forming property and is easy to dissolve.

Step 310: and filtering and defoaming the polyamic acid solution to obtain the spinning solution.

For example, the polyamic acid solution may be subjected to filtration treatment using a microporous filtration membrane, where the microporous filtration membrane may be a polytetrafluoroethylene membrane having a pore size of 0.45 μm. Then, the filtered filtrate may be left for 12 to 24 hours, so that the small bubbles are completely removed by visual observation, and the spinning solution is obtained.

As one possible implementation, fig. 4 shows a schematic flowchart three of a method for preparing a gas separation membrane according to an exemplary embodiment of the present disclosure. As shown in fig. 4, the above-described washing and drying treatment of the prefabricated gas separation membrane is performed to obtain a gas separation membrane, comprising:

step 400: immersing the prefabricated gas separation membrane in a second organic solvent for cleaning. To remove the organic solvent and water in the polyamic acid fiber film. It should be understood that the cleaning time here may be 1 hour or more to ensure that the organic solvent and water within the polyamic acid fiber film can be completely removed.

The second organic solvent may be an alcohol organic solvent, and the alcohol organic solvent may be a monohydric alcohol organic solvent, which may include one or more of methanol, ethanol, and propanol, for example. For example, the monohydric alcohol organic solvent may include methanol, may include ethanol, may include propanol, may also include methanol and ethanol, and the like, without being limited thereto.

Step 410: immersing the prefabricated gas separation membrane cleaned by the second organic solvent into a third organic solvent for cleaning, and obtaining the cleaned prefabricated gas separation membrane. The third organic solvent can be selected from low-boiling organic solvents with good intersolubility with the second organic solvent, so that the third organic solvent can be removed through a subsequent drying process after the second organic solvent in the polyamic acid fiber film is removed. It should be understood that the cleaning time here may be 1 hour or more to ensure that the second organic solvent within the polyamic acid fiber film can be completely removed.

The third organic solvent may include one or more of n-hexane, cyclohexane, isooctane, and methyl isopropyl ketone, for example. For example, the third organic solvent may include n-hexane, may include cyclohexane, may include isooctane, may include methyl isopropyl ketone, may also include n-hexane and cyclohexane, and the like, without being limited thereto.

Step 420: and under the third reaction condition, drying and thermally imidizing the cleaned prefabricated gas separation membrane to obtain the gas separation membrane. It is to be understood that the third reaction conditions herein may include a drying temperature of 50-80 deg.c to prevent the problem of deterioration of mechanical properties of the polyimide fiber membrane due to deformation of the stopper holes in the polyimide fiber membrane caused by an excessively high drying temperature while improving efficiency. For example, the drying temperature may be 50 ℃, 70 ℃, 80 ℃ or the like, and is not limited thereto. The heating rate of the thermal imidization can be 1 ℃/min to 5 ℃/min so as to ensure that the thermal imidization reaction of the polyamic acid is more uniform. For example, the temperature rise rate may be 1℃per minute, 2℃per minute, 5℃per minute, or the like, and is not limited thereto. The temperature of thermal imidization may be 250-350 ℃ to ensure that the polyamic acid can be fully reacted to polyimide. For example, the thermal imidization temperature may be 250 ℃, 300 ℃, 350 ℃ or the like, and is not limited thereto. The thermal imidization time may be 1h to 4h so that the thermal imidization reaction is complete. For example, the thermal imidization time may be 1h, may be 1.5h, may be 4h, or the like, and is not limited thereto.

In some alternatives, the drying and thermal imidization treatment of the cleaned prefabricated gas separation membrane under the third reaction condition to obtain a gas separation membrane may include: and under the third reaction condition, drying the cleaned prefabricated gas separation membrane. And then carrying out thermal imidization treatment on the dried prefabricated gas separation membrane by using a step heating mode to obtain the gas separation membrane. Through the mode that uses the ladder to intensify, make the temperature rise to reaction temperature fast at first ladder temperature, when the temperature reaches reaction temperature, can reduce the rate of rising temperature to extension reaction time, make the reaction more even, abundant.

The present disclosure is further illustrated by way of examples below, but is not thereby limited to the scope of the examples described. The experimental methods, in which specific conditions are not noted in the following examples, were selected according to conventional methods and conditions, or according to the commercial specifications.

Example 1

The embodiment is used for preparing polyimide resin, wherein the selected diamine monomer is 4,4' -diamine diphenyl ether, the selected organic solvent is N, N-dimethylformamide, the reaction temperature is-20 ℃, the selected inert gas is nitrogen, and the mass ratio of triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to diamine monomer is 1:1, the catalyst is pyridine, and the dehydrating agent is acetic anhydride.

The first step: preparation of polyamic acid solution

The dried flask is vacuumized and filled with nitrogen, 4' -diaminodiphenyl ether (4 mmol) is added into the flask, dried N, N-dimethylformamide (10 mL) is added into the flask and stirred uniformly, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride (4 mmol) is slowly and uniformly added into the flask at a low temperature of-20 ℃ and stirred uniformly, and then the polyamic acid solution is prepared. The mass fraction of polyamic acid in the polyamic acid solution was 21.9%.

And a second step of: preparation of polyimide resin

1mL of pyridine and 1mL of acetic anhydride are added, nitrogen is introduced at room temperature and stirred for 10min, the temperature is raised to 100 ℃ and stirred for 3h to complete chemical imidization, the mixture is cooled to room temperature, 200mL of methanol is poured into the mixture to obtain polyimide precipitate, the polyimide precipitate is washed with the methanol for three times and filtered, and then the polyimide resin is obtained by vacuum drying in an oven at 160 ℃ in the temperature, and the solubility of the polyimide resin prepared in the embodiment is shown in Table 1.

Example 2

The embodiment is used for preparing polyimide resin, wherein the selected diamine monomer is 2, 2-bis (4-aminophenyl) hexafluoropropane, the selected organic solvent is dimethylacetamide, the reaction temperature is-80 ℃, the selected inert gas is nitrogen, and the mass ratio of triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to diamine monomer is 1:1.2, the catalyst is pyridine, and the dehydrating agent is acetic anhydride.

The first step: preparation of polyamic acid solution

The dried flask was subjected to vacuum pumping and nitrogen gas introduction, 2-bis (4-aminophenyl) hexafluoropropane (3.6 mmol) was added to the flask, followed by addition of dried dimethylacetamide (10 mL) and stirring uniformly, and triptycene-2,3,6,7,14,15-hexanetricarboxylic acid dianhydride (3 mmol) was slowly and uniformly added at a low temperature of-80℃and stirred uniformly to prepare a polyamic acid solution. The mass fraction of polyamic acid in the polyamic acid solution was 21.5%.

And a second step of: preparation of polyimide resin

1mL of pyridine and 1mL of acetic anhydride are added, nitrogen is introduced at room temperature and stirred for 10min, the temperature is raised to 120 ℃ and stirred for 3.5h to complete chemical imidization, the mixture is cooled to room temperature and poured into 200mL of methanol to obtain polyimide precipitate, the polyimide precipitate is washed with methanol for three times and filtered, and then the polyimide resin is obtained by vacuum drying in an oven at 150 ℃ in the condition that the solubility of the polyimide resin prepared in the embodiment is shown in table 1.

Example 3

The embodiment is used for preparing polyimide resin, wherein the selected diamine monomer is 4,4' -diaminobiphenyl, the selected organic solvent is tetrahydrofuran, the reaction temperature is 10 ℃, the selected inert gas is nitrogen, and the mass ratio of triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to diamine monomer is 1:1.5, the catalyst is isoquinoline and the dehydrating agent is acetic anhydride.

The first step: preparation of polyamic acid solution

The dried flask was subjected to vacuum pumping and nitrogen gas introduction, 4' -diaminobiphenyl (6 mmol) was added to the flask, followed by addition of dried dimethylacetamide (10 mL) and stirring uniformly, and triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride (4 mmol) was slowly and uniformly added at a low temperature of-80℃and stirred uniformly to prepare a polyamic acid solution. The mass fraction of polyamic acid in the polyamic acid solution was 23.8%.

And a second step of: preparation of polyimide resin

1mL of isoquinoline and 1mL of acetic anhydride are added, nitrogen is introduced at room temperature and stirred for 10min, the temperature is raised to 80 ℃ and stirred for 4h to complete chemical imidization, the mixture is cooled to room temperature, and poured into 200mL of methanol to obtain polyimide precipitate, the polyimide precipitate is washed with methanol for three times and filtered, and then the polyimide resin is obtained by vacuum drying in an oven at 200 ℃ in the temperature, and the dissolubility of the polyimide resin prepared in the embodiment is shown in Table 1.

Comparative example 1

This comparative example was used to prepare polyimide resins.

The first step: a polyamic acid solution was prepared.

The dried flask was subjected to vacuum pumping and nitrogen gas introduction, 4' -diaminobiphenyl (4 mmol) was added to the flask, dried dimethylacetamide (10 mL) was added thereto and stirred uniformly, and 2,3,6, 7-tetracarboxylic acid triptycene dianhydride (4 mmol) was slowly and uniformly added thereto at a low temperature of-50℃and stirred uniformly to prepare a polyamic acid solution.

And a second step of: polyimide resin was prepared.

1mL of pyridine and 1mL of acetic anhydride are added, stirring is carried out for 30min at room temperature, heating is carried out to 100 ℃ and stirring is carried out for 3h to complete chemical imidization, cooling is carried out to room temperature, 200mL of methanol is poured into the mixture to obtain polyimide precipitate, the polyimide precipitate is washed with methanol for three times and filtered, 160 ℃ and vacuum drying is carried out to obtain polyimide resin, and the dissolubility of the polyimide resin prepared in the comparative example is shown in Table 1.

Comparative example 2

This comparative example was used to prepare polyimide resins.

The first step: a polyamic acid solution was prepared.

The dried flask was subjected to a vacuum-pumping and nitrogen-introducing operation, 4 '-diaminobiphenyl (4 mmol) was added to the flask, and dried dimethylacetamide (10 mL) was added thereto and stirred uniformly, and 4,4' - (hexafluoroisopropenyl) diphthalic anhydride (4 mmol) was slowly and uniformly added thereto at a low temperature of-50℃and stirred uniformly to prepare a polyamic acid solution.

And a second step of: polyimide resin was prepared.

Table 1: solubility test table for polyimide resin

	NMP	DMAc	THF	DMSO	DMF
						Example 1	-	-	-	-	-
Example 2	-	-	-	-	-
						Example 3	-	-	-	-	-
Comparative example 1	+	+	+	+	+
						Comparative example 2	+	+	+	+	+

"+" represents soluble at normal temperature and "-" represents insoluble at normal temperature

As can be seen from Table 1, the polyimide resins prepared in examples 1 to 3 were insoluble in several organic solvents such as N-methylpyrrolidone, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, and N, N-dimethylformamide, whereas the polyimide resins prepared in comparative example 1 using the dianhydride having a triptycene structure and the diamine monomer were soluble in several organic solvents such as N-methylpyrrolidone, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide, and N, N-dimethylformamide, and thus the polyimide resins prepared in the preparation methods of the polyimide resins provided in the exemplary embodiments of the present disclosure were excellent in solvent resistance.

Example 4

This example was used to prepare polyimide gas separation membranes. The diamine monomer is 4,4' -diamine diphenyl ether, the organic solvent is N, N-dimethylformamide, the reaction temperature is-20 ℃, the inert gas is nitrogen, and the mass ratio of triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to diamine monomer is 1:1, the catalyst selected is pyridine, the dehydrating agent selected is acetic anhydride, the second organic solvent selected is isopropanol, the coagulating bath selected is a mixed solution of isopropanol and water, and the mass fraction of isopropanol in the coagulating bath is 5%. The second organic solvent for cleaning is isopropanol, and the third organic solvent is isooctane.

The first step: preparation of polyamic acid solution

The dried flask is vacuumized and filled with nitrogen, 4' -diaminodiphenyl ether (0.4 mol) is added into the flask, then dried N, N-dimethylformamide (1L) is added into the flask and stirred uniformly, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride (0.4 mol) is slowly and uniformly added into the flask under the low-temperature environment of-20 ℃ and stirred uniformly, and the polyamic acid solution is prepared. The mass fraction of polyamic acid in the polyamic acid solution was 21.9%.

And a second step of: preparation of spinning solution

The polyamic acid solution was filtered with a polytetrafluoroethylene film of 0.45 μm, and the filtrate was subjected to defoaming treatment until small bubbles were completely removed, to obtain a spinning solution.

And a third step of: preparation of core liquid

Mixing isopropanol and deionized water, defoaming the mixed solution until small bubbles are completely removed, and obtaining core liquid. The mass fraction of the second organic solvent in the core liquid is 50%.

Fourth step: preparation of prefabricated gas separation membranes

The extrusion speed of the spinning solution was adjusted to 150ml/h, and the extrusion speed of the core solution was adjusted to 50ml/h. The height of the air gap is 5cm, the winding speed is 200m/h, the core liquid and the spinning liquid are mixed and extruded into a coagulating bath with the temperature of 20 ℃, and the filament is collected by a filament collecting assembly, so as to obtain the prefabricated gas separation membrane (namely the polyamide acid fiber membrane).

Fifth step: preparation of gas separation membranes

The prefabricated gas separation membrane was immersed in isopropanol for 1h and then in isooctane for 1h. Heating in a vacuum oven at 80 ℃ for a period of time to enable the prefabricated gas separation membrane to be completely dried until the quality is not changed, heating to 200 ℃ at a heating rate of 4 ℃/min in a tube furnace, heating to 300 ℃ at a heating rate of 2 ℃/min, and carrying out thermal imidization for 4 hours to obtain the gas separation membrane, wherein the performances of the polyimide gas separation membrane prepared in the embodiment are shown in Table 2.

Example 5

This example was used to prepare polyimide gas separation membranes. The diamine monomer is 2, 2-bis (4-aminophenyl) hexafluoropropane, the organic solvent is dimethylacetamide, the reaction temperature is-80 ℃, the inert gas is nitrogen, and the mass ratio of triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to diamine monomer is 1:1.2, the catalyst selected is pyridine, the dehydrating agent selected is acetic anhydride, the second organic solvent selected is methanol, the coagulating bath selected is a mixed solution of methanol and water, and the mass fraction of the methanol in the coagulating bath is 25%. The second organic solvent for cleaning is methanol, and the third organic solvent is n-hexane.

The first step: preparation of polyamic acid solution

The dried flask is vacuumized and filled with nitrogen, 2-bis (4-aminophenyl) hexafluoropropane (0.36 mol) is added into the flask, and then dried dimethylacetamide (1L) is added into the flask for uniform stirring, and triptycene-2,3,6,7,14,15-hexanetricarboxylic acid dianhydride (0.3 mol) is slowly and uniformly added into the flask under the low temperature environment of-80 ℃ for uniform stirring, so as to prepare the polyamic acid solution. The mass fraction of polyamic acid in the polyamic acid solution was 21.5%.

And a second step of: preparation of spinning solution

And a third step of: preparation of core liquid

Mixing methanol and deionized water, defoaming the mixed solution until small bubbles are completely removed, and obtaining core liquid. The mass fraction of the second organic solvent in the core liquid is 20%.

Fourth step: preparation of prefabricated gas separation membranes

The extrusion speed of the spinning solution was adjusted to 100ml/h, and the extrusion speed of the core solution was adjusted to 100ml/h. The height of the air gap is 10cm, the winding speed is 100m/h, the core liquid and the spinning liquid are mixed and extruded into a coagulating bath with the temperature of 10 ℃, and the filament is collected by a filament collecting assembly, so as to obtain the prefabricated gas separation membrane (namely the polyamide acid fiber membrane).

Fifth step: preparation of gas separation membranes

The prefabricated gas separation membrane is soaked in methanol for 1h and then soaked in n-hexane for 1h. Heating in a vacuum oven at 50 ℃ for a period of time to enable the prefabricated gas separation membrane to be completely dried until the quality is not changed, heating to 200 ℃ at a heating rate of 5 ℃/min in a tube furnace, heating to 250 ℃ at a heating rate of 1 ℃/min, and carrying out thermal imidization for 1h to obtain the gas separation membrane, wherein the performances of the polyimide gas separation membrane prepared in the embodiment are shown in Table 2.

Example 6

This example was used to prepare polyimide gas separation membranes. The diamine monomer is 4,4' -diaminobiphenyl, the organic solvent is tetrahydrofuran, the reaction temperature is 10 ℃, the inert gas is nitrogen, and the mass ratio of triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to diamine monomer is 1:1.5, the catalyst is isoquinoline, the dehydrating agent is acetic anhydride, the second organic solvent is ethanol, the coagulating bath is mixed liquid of ethanol and water, and the mass fraction of the ethanol in the coagulating bath is 50%. The second organic solvent for cleaning is ethanol, and the third organic solvent is cyclohexane.

The first step: preparation of polyamic acid solution

The dried flask is vacuumized and filled with nitrogen, 4' -diaminobiphenyl (0.6 mol) is added into the flask, and then dried dimethylacetamide (1L) is added into the flask for uniform stirring, and triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride (0.4 mol) is slowly and uniformly added into the flask under the low-temperature environment of-80 ℃ for uniform stirring, so as to prepare the polyamide acid solution. The mass fraction of polyamic acid in the polyamic acid solution was 23.8%.

And a second step of: preparation of spinning solution

And a third step of: preparation of core liquid

And mixing ethanol and deionized water, defoaming the mixed solution until small bubbles are completely removed, and obtaining core liquid. The mass fraction of the ethanol in the core liquid is 80%.

Fourth step: preparation of prefabricated gas separation membranes

The extrusion speed of the spinning solution was adjusted to 300ml/h, and the extrusion speed of the core solution was adjusted to 60ml/h. The height of the air gap is 20cm, the winding speed is 1000m/h, the core liquid and the spinning liquid are mixed and extruded into a coagulating bath with the temperature of 50 ℃, and the filament is collected by a filament collecting assembly, so as to obtain the prefabricated gas separation membrane (namely the polyamide acid fiber membrane).

Fifth step: preparation of gas separation membranes

The prefabricated gas separation membrane is soaked in ethanol for 1h and then soaked in cyclohexane for 1h. Heating in a vacuum oven at 70 ℃ for a period of time to enable the prefabricated gas separation membrane to be completely dried until the quality is not changed, heating to 200 ℃ at a heating rate of 5 ℃/min in a tube furnace, heating to 350 ℃ at a heating rate of 3 ℃/min, and carrying out thermal imidization for 3.5 hours to obtain the gas separation membrane, wherein the performances of the polyimide gas separation membrane prepared in the embodiment are shown in Table 2.

Comparative example 3

This comparative example was used to prepare a polyimide gas separation membrane. The second organic solvent is isopropanol, the coagulation bath is mixed solution of isopropanol and water, and the mass fraction of the isopropanol in the coagulation bath is 5%. The second organic solvent for cleaning is isopropanol, and the third organic solvent is isooctane.

The first step: preparation of spinning solution

The polyimide resin prepared in comparative example 1 was dissolved in N-methylpyrrolidone to prepare an N-methylpyrrolidone solution of polyimide resin having a mass fraction of 20%, and then filtered with a polytetrafluoroethylene film of 0.45 μm, and defoamed until small bubbles were completely removed to obtain a spinning solution.

And a second step of: preparation of core liquid

And a third step of: preparation of prefabricated gas separation membranes

The extrusion speed of the spinning solution was adjusted to 150ml/h, and the extrusion speed of the core solution was adjusted to 50ml/h. The height of the air gap is 5cm, the winding speed is 200m/h, the core liquid and the spinning liquid are mixed and extruded into a coagulating bath with the temperature of 20 ℃, and the filament is collected by a filament collecting assembly, so that the prefabricated gas separation membrane is obtained.

Fourth step: preparation of gas separation membranes

The prefabricated gas separation membrane was immersed in isopropanol for 1h and then in isooctane for 1h. Heating in a vacuum oven at 200deg.C for a period of time to completely dry the prefabricated gas separation membrane until the quality is not changed, to obtain gas separation membrane, and the performance of the polyimide gas separation membrane prepared in this example is shown in Table 2.

Comparative example 4

The first step: preparation of spinning solution

The polyimide resin prepared in comparative example 2 was dissolved in N-methylpyrrolidone to prepare an N-methylpyrrolidone solution of polyimide resin having a mass fraction of 20%, and then filtered with a polytetrafluoroethylene film of 0.45 μm, and defoamed until small bubbles were completely removed to obtain a spinning solution.

And a second step of: preparation of core liquid

And a third step of: preparation of prefabricated gas separation membranes

Fourth step: preparation of gas separation membranes

The prefabricated gas separation membrane was immersed in isopropanol for 1h and then in isooctane for 1h. The polyimide gas separation membranes prepared in this example were prepared by heating in a vacuum oven at 100 c for a period of time such that the prefabricated gas separation membranes were completely dried until no change in mass occurred, to obtain gas separation membranes, the properties of which are shown in table 2.

The gas separation performance of the polyimide gas separation membrane can be tested by adopting a constant-pressure variable-volume method. Specifically, polyimide gas separation membranes can be used to test H at an operating pressure of 300.15K,0.2MPa ₂ 、N ₂ 、CO、CH ₄ The permeability coefficient P of (c) and the test results are shown in table 2.

The selectivity a of the polyimide gas separation membrane can be determined by calculation of the formula: alpha _i/j ＝P _i /P _j Wherein P is _i 、P _j Permeability coefficients of gases i, j, respectivelyThe test results of the selectivity α of the polyimide gas separation membrane are shown in table 2.

TABLE 2 gas permeability coefficient and selectivity

As can be seen from Table 2, the present disclosure is a polyimide gas separation membrane prepared by reacting a triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride as a dianhydride monomer with diamine monomers of 4,4 '-diaminodiphenyl ether, 2-bis (4-aminophenyl) hexafluoropropane and 4,4' -diaminobiphenyl, respectively, in each of exemplary embodiments 4 to 6, wherein the polyimide gas separation membrane has a three-dimensional network structure, and is prepared for H ₂ 、N ₂ 、CO、CH ₄ The permeability coefficient P of (c) is higher than that of comparative examples 3 and 4, and the selectivity is partially higher than that of comparative examples 3 and 4.

Specifically, comparative example 3 uses a reaction of a triptycene 2,3,6, 7-tetracarboxylic acid dianhydride monomer with 4,4' -diaminobiphenyl to prepare a polyimide gas separation membrane, and the free volume of polyimide can be increased due to the presence of the triptycene structure, but unlike example 6, the polyimide gas separation membrane prepared in comparative example 3 is a linear polyimide gas separation membrane, whereas the polyimide gas separation membrane prepared in example 6 is a polyimide gas separation membrane of three-dimensional network structure, which has a more fixed molecular chain spacing and a poorer mobility of molecular chains than the linear polyimide gas separation membrane, and thus the polyimide gas separation membrane prepared in example 6 has better aging resistance and plasticization resistance, and the polyimide gas separation membrane prepared in example 6 has better permeability and selectivity, as determined by combining the data in table 2.

Comparative example 4 a polyimide gas separation membrane was prepared by using 4,4'- (hexafluoroisopropenyl) diphthalic anhydride reacted with 4,4' -diaminobiphenyl, unlike example 6, dianhydride in comparative example 4 has no triptycene structure and is a linear polyimide, and thus, the polyimide gas separation membrane prepared by the method in example 6 was superior in aging resistance and plasticization resistance, and it was confirmed that the polyimide gas separation membrane prepared in example 6 was superior in permeability by combining the data in table 2.

In the above description, technical details of patterning, etching, and the like of each layer are not described in detail. Those skilled in the art will appreciate that layers, regions, etc. of the desired shape may be formed by a variety of techniques. In addition, to form the same structure, those skilled in the art can also devise methods that are not exactly the same as those described above. In addition, although the embodiments are described above separately, this does not mean that the measures in the embodiments cannot be used advantageously in combination.

The embodiments of the present disclosure are described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. The scope of the disclosure is defined by the appended claims and equivalents thereof. Various alternatives and modifications can be made by those skilled in the art without departing from the scope of the disclosure, and such alternatives and modifications are intended to fall within the scope of the disclosure.

Claims

1. A polyimide resin characterized by having the structural formula:

2. The polyimide resin according to claim 1, wherein R ₁ Any one of the following groups:

3. a gas separation membrane comprising the polyimide resin according to any one of claims 1 to 2.

4. A gas separation membrane according to claim 3, wherein the gas separation membrane is used for separating hydrogen and nitrogen, hydrogen and carbon monoxide, and hydrogen and methane; and/or the number of the groups of groups,

the gas separation membranes have a hydrogen permeability greater than 100barrers, a nitrogen permeability greater than 2.5barrers, a carbon monoxide permeability greater than 2.0barrers, and a methane permeability greater than 2.0barrers.

5. A method for producing a gas separation membrane according to any one of claims 3 to 4, comprising:

Mixing a second organic solvent with water to obtain a core liquid;

6. The method for producing a gas separation membrane according to claim 5, wherein the first reaction conditions include: the reaction temperature is-80 ℃ to 10 ℃, and the reaction protecting gas is inert gas; and/or the number of the groups of groups,

the first organic solvent comprises one or more of N-methylpyrrolidone, dimethylacetamide, tetrahydrofuran, dimethyl sulfoxide and N, N-dimethylformamide; and/or the number of the groups of groups,

the diamine monomer comprises one or more of 4,4 '-diamine diphenyl ether, 2-bis (4-aminophenyl) hexafluoropropane and 4,4' -diaminobiphenyl; and/or the number of the groups of groups,

the mass ratio of the triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to the diamine monomer is 1: (1-1.5); and/or the number of the groups of groups,

the second organic solvent comprises one or more of methanol, ethanol, propanol and acetone; and/or the number of the groups of groups,

the mass fraction of the second organic solvent in the core liquid is 20% -80%; and/or the number of the groups of groups,

The second reaction conditions include: the extrusion speed of the spinning solution is 100ml/h-300ml/h, and the extrusion speed ratio of the spinning solution to the core solution is 1:1-5:1, the air gap height is 5cm-20cm, and the filament collecting speed of the spinning is 100m/h-1000m/h; and/or the number of the groups of groups,

the temperature of the coagulating bath is 10-50 ℃, the coagulating bath is a mixed solution of a second organic solvent and water, and the mass fraction of the second organic solvent in the coagulating bath is 5-50%.

7. The method for producing a gas separation membrane according to claim 5, wherein the step of adding triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride to a mixture of a first organic solvent and a diamine monomer under a first reaction condition comprises:

under the first reaction condition, triptycene-2,3,6,7,14,15-hexacarboxylic acid dianhydride is added into a mixed solution of a first organic solvent and a diamine monomer to obtain a polyamic acid solution, wherein the mass fraction of polyamic acid in the polyamic acid solution is 10% -40%;

and filtering and defoaming the polyamic acid solution to obtain spinning solution.

8. The method for producing a gas separation membrane according to claim 5, wherein the subjecting the prefabricated gas separation membrane to washing and drying processes to obtain a gas separation membrane comprises:

Immersing the prefabricated gas separation membrane into a second organic solvent for cleaning;

immersing the prefabricated gas separation membrane subjected to cleaning by using the second organic solvent into a third organic solvent for cleaning to obtain a cleaned prefabricated gas separation membrane;

and under the third reaction condition, drying and thermally imidizing the cleaned prefabricated gas separation membrane to obtain the gas separation membrane.

9. The method for producing a gas separation membrane according to claim 8, wherein the step of subjecting the washed prefabricated gas separation membrane to a baking and thermal imidization treatment under a third reaction condition to obtain a gas separation membrane comprises:

under the third reaction condition, drying the cleaned prefabricated gas separation membrane;

and carrying out thermal imidization treatment on the dried prefabricated gas separation membrane by using a step heating mode to obtain the gas separation membrane.

10. The method for producing a gas separation membrane according to claim 8, wherein the second organic solvent is an alcohol organic solvent, the alcohol organic solvent is a monohydric alcohol organic solvent, and the monohydric alcohol organic solvent includes one or more of methanol, ethanol, and propanol; and/or the number of the groups of groups,

The third organic solvent comprises one or more of n-hexane, cyclohexane, isooctane and methyl isopropyl ketone; and/or the number of the groups of groups,

the third reaction condition comprises that the drying temperature is 50-80 ℃, and the heating rate of the thermal imidization is 1-5 ℃/min.