CN116023277A - Diamine monomer containing dicyclo side group structure, and preparation method and application thereof - Google Patents
Diamine monomer containing dicyclo side group structure, and preparation method and application thereof Download PDFInfo
- Publication number
- CN116023277A CN116023277A CN202310024226.4A CN202310024226A CN116023277A CN 116023277 A CN116023277 A CN 116023277A CN 202310024226 A CN202310024226 A CN 202310024226A CN 116023277 A CN116023277 A CN 116023277A
- Authority
- CN
- China
- Prior art keywords
- polyimide
- side group
- group structure
- dicyclo
- polyimide film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
- Y02C20/00—Capture or disposal of greenhouse gases
- Y02C20/40—Capture or disposal of greenhouse gases of CO2
Landscapes
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
The invention discloses a diamine monomer containing a dicyclic side group structure, and a preparation method and application thereof. The diamine monomer containing the dicyclo side group structure has a structure shown in any one of the following formulas:
according to the invention, a series of polyimide films are prepared from diamine monomers containing a dicyclic side group structure, and because a large-volume dicyclic substituent is combined with a central benzene ring, the rigidity and steric hindrance of the diamine monomers are obviously improved, so that the prepared polyimide film has high specific surface area and gas permeability coefficient, and the gas separation performance of the polyimide film is superior to that of a commercial gas separation film and a corresponding hexafluorodianhydride gas separation film, and the polyimide film has a good application prospect in the aspects of industrial hydrogen purification and recovery application.
Description
Technical Field
The invention belongs to the technical field, relates to a diamine monomer containing a dicyclic side group structure, a preparation method and application thereof, and in particular relates to a diamine monomer containing a dicyclic side group structure, a preparation method thereof, a polyimide film prepared from the diamine monomer containing the dicyclic side group structure and application thereof in gas separation.
Background
The gas membrane separation technology utilizes different gases in the mixed gas to have different permeabilities to membrane materials, uses the pressure difference of the gases at two sides of the membrane as driving force, obtains gas enriched materials with large permeabilities at the permeate side, and obtains separation gas which is difficult to permeate gas enrichment at the non-permeate side, thereby realizing the purpose of separating the mixed gas. Compared with the traditional separation modes such as low-temperature distillation or adsorption, the membrane separation technology has the advantages of simple equipment, small investment, low energy consumption, convenient use, easy operation, safety, no environmental pollution and the like, and is more and more focused in scientific research and industry.
Polyimide generally has high gas permeability and selectivity, and simultaneously has excellent heat resistance, mechanical properties, chemical stability and other physicochemical properties. These advantages make polyimide an attractive gas separation membrane material. Since 2002, polyimide has been reported to be used in various gas separation fields by Air liquid, praxair, parker-Hannifin and Ube, among others.
Currently, only polyimide separation membranes have been commercialized
And->
It has good mechanical properties, thermodynamic stability and a high selectivity coefficient +. >
In pure CO 2 Is 10barrer, CO 2 /CH 4 The selectivity of (2) is 36, and the low permeability coefficient and the separation efficiency limit the industrial application. The permeation coefficient P and the ideal selection coefficient a are two important indicators for evaluating membrane separation performance. Gas separation membranes with high permeability coefficients and high selectivity coefficients are always the goal of researchers. However, it is the case that the permeability coefficient P and the ideal selection coefficient a of the polymer film tend to exhibit a contradictory relationship (trade-off). I.e., a polymer membrane with a high permeability coefficient, which desirably has a low coefficient of selection; and a polymer membrane with high selectivity has a relatively low permeability coefficient. In 1991, robeson proposed a characteristic limit for a polymer, namely Robeson upper line, describing the equilibrium effect of permeability coefficient and selectivity coefficient. In order to realize high permeation flux and high separation efficiency, the high molecular membrane should have high permeation coefficient and selection coefficient at the same time, so that the Robeson upper limit is broken through, and the preparation of high-performance separation materials becomes a main development direction in the field. The ideal gas separation membrane material needs to have good mechanical property, thermodynamic stability and film forming processability besides high permeability coefficient and selectivity coefficient.
Disclosure of Invention
The invention mainly aims to provide a diamine monomer containing a dicyclic side group structure, and a preparation method and application thereof, so as to overcome the defects of the prior art.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention comprises the following steps:
the embodiment of the invention provides a diamine monomer containing a dicyclic side group structure, which has a structure shown as any one of a formula (I) -a formula (V):
the embodiment of the invention also provides a preparation method of the diamine monomer containing the dicyclo side group structure, which comprises the following steps:
making benzoquinone and diene compound undergo the processes of D-A reaction, reduction, substitution, oxidation, esterification, substitution and oximation reaction in turn so as to obtain diamine monomer containing dicyclo side group structure;
wherein the diene compound comprises any one or more than two of cyclopentadiene, cyclohexadiene, methyl cyclopentadiene, tetramethyl cyclopentadiene and pentamethyl cyclopentadiene.
The embodiment of the invention also provides a polyimide film, which is prepared from polyimide containing a dicyclo side group structure, wherein the polyimide containing the dicyclo side group structure is prepared from the diamine monomer containing the dicyclo side group structure, and the polyimide has a structure shown as a formula (VI):
Wherein n is more than 1 and less than 1000, R 1 A structure selected from the group consisting of any one or a combination of two or more of the following formulas:
R 2 a structure selected from any one of the following formulas:
wherein the dashed line represents the key-in position.
The embodiment of the invention also provides a preparation method of the polyimide film, which comprises the following steps:
providing the diamine monomer containing the dicyclo side group structure;
reacting a mixed reaction system comprising the diamine monomer, the aromatic dianhydride, the catalyst and the solvent for 1-4 hours at 50-100 ℃ in a protective atmosphere to prepare a prepolymer;
heating the prepolymer to 140-200 ℃, and continuing to react for 4-12 hours to prepare polyimide containing a dicyclo side group structure;
and mixing the polyimide containing the dicyclo side group structure with an organic solvent and performing film laying treatment to obtain the polyimide film.
The embodiment of the invention also provides application of the polyimide film in the field of gas separation.
Compared with the prior art, the invention has the beneficial effects that:
(1) According to the polyimide film containing the dicyclic side group structure, diamine containing the dicyclic side group structure with a rigid torsion structure is introduced, so that on one hand, the rigidity of a molecular chain skeleton is increased, and the activity of a molecular chain segment is reduced; on the other hand, the ordered stacking degree of polyimide molecular chain segments is destroyed, the action force among the molecular chains is weakened, the molecular chain distance is increased, the free volume and the specific surface area of polyimide are increased, and the specific surface area is more than 460m 2 g -1 Even up to 580m 2 g -1 ；
(2) The polyimide film pair H containing multiple dicyclo side group structures provided by the invention 2 、CO 2 、O 2 、N 2 、CH 4 The permeability coefficients can exceed 1000, 1470, 295, 95 and 98 Barrers, so that the defects of low permeability coefficient and low separation efficiency of the commercial polyimide gas separation membrane are overcome, and the gas separation efficiency is greatly improved;
(3) The polyimide film containing the dicyclo side group structure provided by the invention has separation performance to hydrogen/methane and hydrogen/nitrogen close to the upper limit of Robeson in 2008, is superior to the corresponding separation performance of hexafluorodianhydride polyimide, and has great potential in industrial hydrogen purification and recovery application.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings may be obtained according to the drawings without inventive effort to those skilled in the art.
FIGS. 1 a-1 d are nuclear magnetic resonance hydrogen spectra of diamines containing a dicyclic pendant structure prepared in examples 1-4 of the present invention;
FIGS. 2a to 2d are nuclear magnetic patterns of polyimide films containing a dicyclo-side group structure prepared in example 1 of the present invention;
FIG. 3 is a graph of the ultraviolet-visible spectrum of a polyimide film having a dicyclic pendant structure prepared in example 1 of the present invention;
FIGS. 4 a-4 c show the polyimide films containing bicyclic pendant structures of examples 1, 2, 5 of the present invention, and the pairs of seven commercial gas separation membranes of the prior art, hexafluorodianhydride, H 2 /CH 4 Is a gas separation performance graph of (1);
FIGS. 5 a-5 c show the polyimide films containing bicyclic pendant structures of examples 1, 2, 5 of the present invention, and the pairs of seven commercial gas separation membranes of the prior art, hexafluorodianhydride, H 2 /N 2 Is a gas separation performance graph of (a).
Detailed Description
In view of the defects of the prior art, the inventor of the present invention has provided a technical scheme of the present invention through long-term research and a great deal of practice, mainly by adopting p-benzoquinone and diene compounds as initial raw materials, synthesizing diamine compounds with large alicyclic side groups through D-A reaction, reduction, oxidation, esterification, substitution, oximation reaction and the like; and the polyimide film containing the double-ring side group structure is prepared by taking the prepared diamine and dianhydride monomers containing the double-ring side group structure as raw materials through polymerization reaction and subsequent processing steps, and analysis and test data show that the polyimide film containing the double-ring side group structure prepared by the technical scheme of the invention has excellent permeability and selectivity.
The following description of the present invention will be made clearly and fully, and it is apparent that the embodiments described are some, but not all, of the embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Specifically, as one aspect of the technical scheme of the invention, the diamine monomer containing the dicyclo side group structure has a structure shown in any one of the formulas (I) - (V):
in another aspect, the present invention further provides a method for preparing the diamine monomer containing a dicyclic side group structure, which includes:
wherein the diene compound comprises any one or more than two of cyclopentadiene, cyclohexadiene, methyl cyclopentadiene, tetramethyl cyclopentadiene and pentamethyl cyclopentadiene.
In some preferred embodiments, the diene compound has a structure as shown in any one of the following formulas:
further, the cyclopentadiene was purchased from milin, cyclohexadiene was purchased from enoKai, and methylcyclopentadiene, tetramethylcyclopentadiene, pentamethylcyclopentadiene, sigma-Aldrich were purchased from Inochi.
In some preferred embodiments, the catalyst used in preparing the diamine monomer having a bicyclic pendant structure comprises methyl rhenium trioxide, commercially available from Sigma-Aldrich company.
In some preferred embodiments, solvents required to prepare the diamine monomer containing a bicyclic pendant structure include, but are not limited to, ethanol, ethyl acetate, petroleum ether, acetone, chloroform, tetrahydrofuran, N-dimethylformamide, diethyl ether, and the like.
In some preferred embodiments, the method for preparing a diamine monomer having a bicyclic pendant structure further comprises: after the reaction is completed, the reaction system is cooled to room temperature, the obtained mixture is filtered, filtrate is collected and concentrated to obtain a crude product, and the crude product is subjected to recrystallization and/or column chromatography separation and then vacuum drying to obtain an intermediate product and a final diamine monomer.
Further, the filtration operation uses a G3 or G4 sand core funnel.
Further, the column chromatography adopts 200-300 mesh silica gel, the eluent adopts ethyl acetate and dichloromethane, and the solvent ratio is 1:10-30 (v/v); ethyl acetate and petroleum ether, the solvent ratio is 1:1-10 (v/v).
Further, the product solid obtained by recrystallization and/or column chromatography is dried for 6-12 hours at 80-120 ℃ in vacuum.
In another aspect of the embodiment of the present invention, there is provided a polyimide film, wherein the polyimide film is made of a polyimide containing a dicyclo side group structure, and the polyimide containing a dicyclo side group structure is made of the diamine monomer containing a dicyclo side group structure, and the polyimide has a structure as shown in formula (VI):
wherein n is more than 1 and less than 1000, R 1 A structure selected from the group consisting of any one or a combination of two or more of the following formulas:
wherein the dashed line represents the access position of the anhydride.
R 2 A structure selected from any one of the following formulas:
wherein the dashed line represents the access position of the amino group.
In some preferred embodiments, the polyimide film has a thermal decomposition temperature of 400 ℃ or higher at a weight loss of 5wt% under a nitrogen atmosphere; the specific surface area of the polyimide film is 100m 2 And/g.
In some preferred embodiments, the polyimide film has a thickness of 50 to 80 μm.
Another aspect of the embodiment of the present invention further provides a method for preparing the foregoing polyimide film, which includes:
providing the diamine monomer containing the dicyclo side group structure;
reacting a mixed reaction system comprising the diamine monomer, the aromatic dianhydride, the catalyst and the solvent for 1-4 hours at 50-100 ℃ in a protective atmosphere to prepare a prepolymer;
Heating the prepolymer to 140-200 ℃, and continuing to react for 4-12 hours to prepare polyimide containing a dicyclo side group structure;
and mixing the polyimide containing the dicyclo side group structure with an organic solvent and performing film laying treatment to obtain the polyimide film.
In some preferred embodiments, the protective atmosphere is selected from nitrogen and/or an inert gas, including argon.
In some preferred embodiments, the aromatic dianhydride comprises hexafluoroisopropyl phthalic anhydride, 3',4' -benzophenone tetracarboxylic dianhydride, 3',4' -biphenyl tetracarboxylic dianhydride, 2, 3',4' -biphenyltetracarboxylic dianhydride, 4' -biphenyldianhydride, 9-bis (3, 4-dicarboxyphenyl) fluorene dianhydride, 3, 4-diphenylalum tetracarboxylic dianhydride, 1,4,5, 8-tea tetracarboxylic anhydride 9, 9-bis (trispeamethyl) -2,3,6, 7-oxa-tetracarboxyl dianhydride, pyromellitic dianhydride, bicyclo [2.2.2] oct-7-ene-2, 3,5, 6-tetracarboxylic dianhydride, norbornane-2-spiro-alpha-cycloalkanone-alpha ' -spiro-2 ' -norbornane-5, 5 ', 6,6 ' -tetracarboxylic dianhydride, 3' -tetramethyl 2,2',3,3' -tetrahydro-1, 1-spirobiindene tetracarboxylic dianhydride, 7' -spirobiindene [ 7H-cyclopentadiene [ g ] isobenzofuran [5,6-b ] [1,4] benzodioxin ] -1,1', any one or a combination of two or more of 3,3' -tetralone, 8', 9' -tetrahydro-9,9,9 ',9' -tetramethyl tetracarboxylic dianhydride, and is not limited thereto.
In some preferred embodiments, the catalyst comprises a basic catalyst and/or an acidic catalyst, wherein the acidic catalyst comprises benzoic acid and/or parahydroxybenzoic acid; the basic catalyst includes any one or a combination of two or more of triethylamine, tripropylamine, tributylamine, and isoquinoline, and is not limited thereto.
Further, the basic catalyst includes isoquinoline and/or triethylamine, and is not limited thereto.
In some preferred embodiments, the solvent includes any one or a combination of two or more of m-cresol, p-chlorophenol, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, and is not limited thereto.
In some preferred embodiments, the molar ratio of diamine monomer, aromatic dianhydride to catalyst is 1:1:0.5 to 3. Carrying out
In some preferred embodiments, the method of making further comprises: after the prepolymer reaction is completed, a precipitant is added to the resultant mixture, followed by a Soxhlet extraction treatment.
Further, the precipitating agent includes any one or a combination of two or more of methanol, ethanol, acetone, petroleum ether, and water, and is not limited thereto.
In some preferred embodiments, the film laying process comprises: mixing polyimide containing a dicyclo side group structure with an organic solvent to form a solution with the mass fraction of 1-10%, spreading a film on a substrate by adopting a tape casting method, and then performing temperature programming treatment, drying and demolding treatment.
Further, the organic solvent includes any one or a combination of two or more of tetrahydrofuran, dichloromethane, chloroform, m-cresol, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, and is not limited thereto.
Further, the temperature of the drying treatment is 50-100 ℃ and the drying time is 6-20 h.
Further, the temperature programming process includes: the room temperature is raised to 60-80 ℃ for heat preservation for 6-10 h, then is raised to 80-120 ℃ for heat preservation for 2-5h, then is raised to 120-150 ℃ for heat preservation for 3-6h, and finally is raised to 200-300 ℃ for heat preservation for 2-5h.
In some more specific embodiments, the method for preparing a polyimide film specifically includes:
(1) Under the protection of protective atmosphere, a mixed reaction system containing diamine monomer containing a dicyclic side group structure, aromatic dianhydride, catalyst and solvent reacts for 1-4 hours at 50-100 ℃ to prepare a polyamic acid solution (the prepolymer);
(2) Heating the polyamic acid solution generated in the steps to 140-200 ℃, and reacting for 4-12 hours to convert the polyamic acid into polyimide;
(3) Pouring polyimide solution containing the dicyclo side group structure generated in the steps into a poor solvent to be separated out, and carrying out Soxhlet extraction on the obtained solid for 1-2 days;
and (3) drying the polyimide solid generated in the steps in a sublimation tube, dissolving the polyimide solid in a soluble solvent, and performing film laying treatment with the solid content of 3-15% to obtain the polyimide film containing the dicyclo side group structure.
Another aspect of the embodiments of the present invention also provides the use of the foregoing polyimide film in the field of gas separation.
Further, the use is the use of the polyimide film in separating hydrogen, methane, carbon dioxide or oxygen.
For example, the use is the separation of hydrogen/methane or hydrogen/nitrogen gas pairs by the polyimide film.
For example, the use is the separation of carbon dioxide/methane or carbon dioxide/nitrogen gas pairs by the polyimide film.
For example, the use is the separation of the polyimide film from an oxygen/nitrogen gas pair.
The technical scheme of the present invention is further described in detail below with reference to several preferred embodiments and the accompanying drawings, and the embodiments are implemented on the premise of the technical scheme of the present invention, and detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.
The experimental materials used in the examples described below, unless otherwise specified, were all commercially available from conventional biochemicals.
Example 1
1.1 Synthesis of DMNDA monomer
(1) Freshly distilled cyclopentadiene (2.64 g,40 mmol) was purified at 0deg.C and N 2 A solution of p-benzoquinone (2.16 g,20 mmol) in ethanol (20 mL) was added dropwise under an atmosphere. The mixture was stirred at room temperature for 8 hours. The precipitate was collected by filtration, washed with cold ethanol and dried in vacuo to give 4.7g of product I as colourless in 99% yield.
(2) A solution of I (1.2 g,5 mmol) in an ethyl acetate-ethanol (1:1) mixture (20 mL) containing 10% Pd/C (20 mg) was hydrogenated by adding 2.5MPa hydrogen to the reactor apparatus. After 8 hours, after natural cooling to room temperature, the insoluble catalyst was removed by suction filtration through a G-4 funnel and washed with dichloromethane (20 mL). The filtrate was concentrated under reduced pressure to filter, and the solid was dried in vacuo to give colorless crystalline solid II in 98% yield (1.9 g).
(3) A solution of II (2.44 g,10 mmol) in chloroform (20 mL) was stirred at room temperature and at N 2 A solution of Br2 (1.6 g,10 mmol) in chloroform (20 mL) was slowly added dropwise over 0.5 hour under an atmosphere, and the resulting suspension was stirred at room temperature for 8 hours. The resulting suspension was cooled in an ice-acetone bath for 1 hour and the precipitate was filtered under vacuum and washed with cold chloroform to give 98% brown solid III.
(4) III (8.48 g,35 mmol), p-toluenesulfonyl chloride (15.650 g,83 mmol) and methylene chloride (600 mL) were placed in a three-necked round bottom flask and stirred under nitrogen at 0deg.C for 1h, after which slow triethylamine (8.938 g,88.33 mol) was added dropwise with stirring at 0deg.C. After the completion of the dropwise addition, the temperature was raised to 25℃and stirring was continued for 20 hours. The mixture was thoroughly washed with deionized water (3X 500 mL) and then dried over magnesium sulfate. The methylene chloride was removed by rotary evaporation, and the crude product was recrystallized from ethanol to give pale yellow crystals IV (15.4 g) in 80% yield.
(5) IV (27.5 g,50 mmol), toluene (100 mL) and anhydrous DMF (300 mL) were placed in a three-necked round bottom 500mL flask equipped with a Dean-Stark apparatus, condenser, magnetic stirrer and air inlet. After the mixture was heated to 140℃under a nitrogen atmosphere and reacted for 1 hour, toluene and residual water in the reaction solvent were removed from the system as an azeotrope by distillation. After 4h, potassium o-phenylenediamine (20.50 g,110 mmol) and 18-crown-6 (2.640 g,10 mmol) were added and reacted at 140℃for 48h, after cooling to room temperature, the dark brown solution was poured into 800mL of deionized water. The mixture was extracted with chloroform (3×400 mL) and the organic solvent was dried over magnesium sulfate. Chloroform was removed by rotary evaporation to give a crude product which was further purified by washing with ethanol to give an off-white solid powder V (7.5 g) in 30% yield.
(6) V (26.0 g,52 mmol) and 6M HCI in acetic acid (137.5 mL) were placed in a 500mL three-necked round bottom flask equipped with a mechanical stirrer and condenser. The mixture was then heated at 140 ℃ for 45 hours, cooled to room temperature and the precipitate (phthalic acid) was removed by filtration. The filtrate was thoroughly washed with diethyl ether (3X 200 mL). The aqueous phase was collected and concentrated under reduced pressure, and the crude product was further purified by ethanol recrystallization to give 85% yield as a pale yellow solid (13.75 g) as DMNDA. (the nuclear magnetic hydrogen spectrogram is shown in figure 1 a).
1.2 polymerization of DMNDA diamine monomer
In this example, the structural formula of the DMNDA diamine based polyimide is as follows: (the nuclear magnetic hydrogen spectrogram is shown in fig. 2 a-2 d).
The polymerization reaction comprises the following steps:
1.2.1 in this example, the 6FDA-DMNDA polyimide has the structure of the formula:
into the flask, hexafluoroisopropyl phthalic anhydride (6 FDA) (1.110 g,2.5 mmol), DMNDA (0.6 g,2.5 mmol), benzoic acid (0.1527 g,1.25 mmol) and m-cresol (6.5 g) were added under nitrogen atmosphere to control the solid content of the system to 20wt%. The reaction was continued for 8h at 80℃with mechanical stirring until complete dissolution of the reactants, increasing the temperature to 180℃and complete imidization of the polymer. M-cresol (24.40 g) was added, the solid content of the system was diluted to 5wt%, heating was stopped, and the temperature was naturally lowered to room temperature. The reaction solution was poured into a magnetically stirred ethanol and water mixture (300 ml, v/v=1:1), and a filiform white fibrous solid was precipitated and filtered. Placing the filamentous fiber solid into a Soxhlet extractor, heating and refluxing with ethanol for 18h, removing redundant m-cresol, and drying at 120 ℃ after the completion of the refluxing to obtain polyimide containing a DMNDA structure, wherein a nuclear magnetic resonance hydrogen spectrum is shown in figure 2a.
The polyimide containing the dicyclo side group structure is dissolved in chloroform to prepare a solution with the solid content of 5wt%, insoluble substances and impurities are removed by filtration, air bubbles are eliminated by vacuumizing, and the polyimide solution is slowly poured onto a flat, smooth and dry glass surface dish by adopting a tape casting method. And (3) placing the glass surface dish into a film spreading oven, drying at room temperature for 12 hours, and then completely soaking the glass plate into distilled water until the film naturally drops off, thus obtaining the polyimide film (marked as 6 FDA-DMNDA) containing the double-ring side group structure.
Its surface area is 469m by BET test 2 Per gram, measured by gas separation tests at 1barrer and 35 ℃, the permeability coefficient of nitrogen is 95.7barrer, the permeability coefficient of oxygen is 295barrer, the permeability coefficient of hydrogen is 1055barrer, the permeability coefficient of methane is 98.2barrer, the permeability coefficient of carbon dioxide is 1473barrer, the permeability selectivity of carbon dioxide/methane is 15.1, the permeability selectivity of carbon dioxide/nitrogen is 15.4, the temperature of 5% thermal weight loss under nitrogen is 454 ℃, and the glass transition temperature is 419 ℃.
1.2.2 in this example, the Co-CpODA-DMNDA-0.8 polyimide has the structure of the formula:
the preparation of the polyimide gas separation membrane mainly comprises the following steps:
Under the protection of nitrogen atmosphere, 0.2292g (0.516 mmol) of 6FDA and 0.7933g (2.064 mmol) of CpODA dianhydride and 0.6201g (2.58 mmol) of DMNDA and 0.1578g (1.29 mmol) of benzoic acid are placed in a three-port polymerization bottle, 7.6g of anhydrous m-cresol solution is added to enable the solid content of the whole system to be 20wt%, after mechanical stirring is adjusted to a proper rotating speed, the system is heated to 80 ℃ for stirring for 1-2 h to enable the whole system to be dissolved, a transparent light yellow color solution is formed, after the solid is completely dissolved, the system is heated to 180 ℃ for thermal imidization, reaction is carried out for 8-10 h to enable polyimide to be completely thermal imidization, 10.5g of m-cresol is added to enable the solid content of the system to be reduced to 9wt%, heating is turned off, cooling is carried out to 80 ℃, 300ml of methanol is placed on a magnetic stirrer for stirring, the reaction solution is slowly placed in methanol to obtain white filamentous solid, the filamentous solid is placed on the magnetic stirrer for stirring for 2-3 h, the filamentous solid is placed on the magnetic stirrer for filtering, the filamentous solid is placed on the 12 ℃ for extraction, the polyimide is placed in a rope for extraction, and the polyimide is removed under the condition, namely the polyimide is dried under vacuum condition, and the polyimide residue can be removed under the condition.
Dissolving the polymer (0.5 g) in chloroform (25 ml) to prepare a solution with the solid content of 10%, fully stirring until the solution is completely dissolved, filtering insoluble substances by a filter head with the thickness of 0.45 mu m, spreading a film by a tape casting method, spreading the film on a clean glass dish, shaking uniformly until no bubble exists, covering the glass dish with a slightly large glass dish to prevent impurities from falling into the glass dish, placing the glass dish in a glass box, gradually evaporating the solvent at room temperature until the solvent is dried to form a film, and taking off the film by forceps to obtain a polyimide film (marked as Co-CpODA-DMNDA-0.8), wherein a nuclear magnetic hydrogen spectrogram is shown in figure 2d.
Its surface area is 497m by BET test 2 Per gram, measured by gas separation tests at 1barrer and 35 ℃, the permeability coefficient of nitrogen is 45.4barrer, the permeability coefficient of oxygen is 156barrer, the permeability coefficient of hydrogen is 727barrer, the permeability coefficient of methane is 50.6barrer, the permeability coefficient of carbon dioxide is 750barrer, the permeability selectivity of carbon dioxide/methane is 14.8, the permeability selectivity of carbon dioxide/nitrogen is 16.5, the temperature of 5% of thermal weight loss under nitrogen is 452 ℃, and the glass transition temperature is > 450 ℃.
Example 2
2.1 Synthesis of DENDA monomer
(1) Freshly distilled cyclohexadiene (3.20 g,40 mmol) was added dropwise to a solution of ice-cold p-benzoquinone (2.16 g,20 mmol) in ethanol (20 mL) at 0deg.C under N2 atmosphere. The mixture was stirred at room temperature for 8 hours. The precipitate was collected by filtration, washed with cold ethanol and dried in vacuo to give 5.3g of product I as colourless in 99% yield.
(2) A solution of I (1.3411 g,5 mmol) in an ethyl acetate-ethanol (1:1) mixture (20 mL) containing 10% Pd/C (20 mg) was hydrogenated in a reactor apparatus with the addition of 2.5MPa hydrogen. After 8 hours, after natural cooling to room temperature, the insoluble catalyst was removed by suction filtration through a G-4 funnel and washed with dichloromethane (20 mL). The filtrate was concentrated under reduced pressure to filter, and the solid was dried in vacuo to give colorless crystalline solid II in quantitative yield (1.3 g).
(3) A solution of II (2.7 g,10 mmol) in chloroform (20 mL) was stirred at room temperature and a solution of Br2 (1.6 g,10 mmol) in chloroform (20 mL) was slowly added dropwise over 0.5 hour under an N2 atmosphere and the resulting suspension was stirred at room temperature for 8 hours. The resulting suspension was cooled in an ice-acetone bath for 1 hour and the precipitate was filtered under vacuum and washed with cold chloroform to give 98% brown solid III.
(4) III (9.460 g,35 mmol), p-toluenesulfonyl chloride (15.650 g,83 mmol) and methylene chloride (600 mL) were placed in a three-necked round bottom flask and stirred at 0deg.C under nitrogen for 1h, after which slow triethylamine (8.938 g,88.33 mol) was added dropwise with stirring at 0deg.C. After the completion of the dropwise addition, the temperature was raised to 25℃and stirring was continued for 20 hours. The mixture was thoroughly washed with deionized water (3X 500 mL) and then dried over magnesium sulfate. The methylene chloride was removed by rotary evaporation, and the crude product was recrystallized from ethanol to give pale yellow crystals IV (16.18 g) in 80% yield.
(5) IV (28.9 g,50 mmol), toluene (100 mL) and anhydrous DMF (300 mL) were placed in a three-necked round bottom 500mL flask equipped with a Dean-Stark apparatus, condenser, magnetic stirrer and air inlet. After the mixture was heated to 140℃under a nitrogen atmosphere and reacted for 1 hour, toluene and residual water in the reaction solvent were removed from the system as an azeotrope by distillation. After 4h, potassium o-phenylenediamine (20.50 g,110 mmol) and 18-crown-6 (2.640 g,10 mmol) were added and reacted at 140℃for 48h, after cooling to room temperature, the dark brown solution was poured into 800mL of deionized water. The mixture was extracted with chloroform (3×400 mL) and the organic solvent was dried over magnesium sulfate. Chloroform was removed by rotary evaporation to give a crude product which was further purified by washing with ethanol to give an off-white solid powder V (7.9 g) in 30% yield.
(6) V (27.48 g,52 mmol) and 6M HCI in acetic acid (137.5 mL) were placed in a 500mL three-necked round bottom flask equipped with a mechanical stirrer and condenser. The mixture was then heated at 140 ℃ for 45 hours, cooled to room temperature and the precipitate (phthalic acid) was removed by filtration. The filtrate was thoroughly washed with diethyl ether (3X 200 mL). The aqueous phase was collected and concentrated under reduced pressure, and the crude product was further purified by ethanol recrystallization to give 85% yield as a pale yellow solid (14.99 g) as Denda. (the nuclear magnetic hydrogen spectrogram is shown in figure 1 b).
2.2 polymerization of DENDA diamine monomer
In this embodiment, the structural formula of the polyimide based on the DENDA diamine is as follows:
2.2.1 in this embodiment, the SBI-DENDA polyimide has the structure of the formula
SBI (1.571 g,2.5 mmol), DENDA (0.67 g,2.5 mmol), benzoic acid (0.1527 g,1.25 mmol) and meta-cresol (6.9 g) were added to the flask under nitrogen, and the solid content of the system was controlled to 20wt%. The reaction was continued for 8h at 80℃with mechanical stirring until complete dissolution of the reactants, increasing the temperature to 180℃and complete imidization of the polymer. M-cresol (24.80 g) was added, the solid content of the system was diluted to 5wt%, heating was stopped, and the temperature was naturally lowered to room temperature. The reaction solution was poured into a magnetically stirred ethanol and water mixture (300 ml, v/v=1:1), and a filiform white fibrous solid was precipitated and filtered. Placing the filamentous fiber solid into a Soxhlet extractor, heating and refluxing with ethanol for 18h, removing redundant m-cresol, and drying at 120 ℃ after the completion of the removal of the m-cresol to obtain polyimide containing a DENDA structure.
The polyimide containing the dicyclo side group structure is dissolved in chloroform to prepare a solution with the solid content of 5wt%, insoluble substances and impurities are removed by filtration, air bubbles are eliminated by vacuumizing, and the polyimide solution is slowly poured onto a flat, smooth and dry glass surface dish by adopting a tape casting method. And (3) placing the glass surface dish into a film spreading oven, drying at room temperature for 12 hours, and then completely soaking the glass plate in distilled water until the film naturally drops off, thus obtaining the polyimide film (marked as SBI-DENDA) containing the double-ring side group structure.
Through gas separation tests, the permeation coefficient of nitrogen is 113.5 barrers, the permeation coefficient of oxygen is 375.4 barrers, the permeation coefficient of hydrogen is 1456 barrers, the permeation coefficient of methane is 156.4 barrers, the permeation coefficient of carbon dioxide is 1583 barrers, the permeation selectivity of carbon dioxide/methane is 10.2, the permeation selectivity of carbon dioxide/nitrogen is 13.9, the temperature of 5% thermal weight loss under nitrogen condition is 458 ℃ and the glass transition temperature is > 450 ℃.
2.2.2 in this example, co-CpODA-DENDA-0.8 polyimide has the structure of the formula
The preparation of the polyimide gas separation membrane mainly comprises the following steps:
Under the protection of nitrogen atmosphere, 0.2292g (0.516 mmol) of 6FDA and 0.7933g (2.064 mmol) of CpODA dianhydride and 0.6924g (2.58 mmol) of DENDA and 0.1578g (1.29 mmol) of benzoic acid are placed in a three-port polymerization bottle, 7.6g of anhydrous m-cresol solution is added to enable the solid content of the whole system to be 20wt%, after mechanical stirring is adjusted to a proper rotating speed, the system is heated to 80 ℃ for stirring for 1-2 h to enable the whole system to be dissolved, a transparent light yellow color solution is formed, after the solid is completely dissolved, the system is heated to 180 ℃ for thermal imidization, reaction is carried out for 8-10 h to enable polyimide to be completely thermal imidization, 10.5g of m-cresol is added to enable the solid content of the system to be reduced to 9wt%, heating is turned off, cooling is carried out to 80 ℃, 300ml of methanol is placed on a magnetic stirrer for stirring, the reaction solution is slowly placed in methanol to obtain white filamentous solid, the filamentous solid is placed on the magnetic stirrer for stirring for 2-3 h, the filamentous solid is placed on the magnetic stirrer for filtering, the filamentous solid is placed in a 12 ℃ for extracting rope, and then the polyimide is removed by a solvent, namely the polyimide residue can be dried under vacuum condition, namely 120 m-cresol structure.
The polymer (0.5 g) was dissolved in chloroform (25 ml) to prepare a solution with a solid content of 1 0%, the solution was stirred sufficiently until the insoluble matter was completely dissolved, the insoluble matter was filtered off with a 0.45 μm filter head, the solution was spread by casting, spread on a clean glass dish, shaken uniformly until no air bubbles were formed, covered with a slightly larger glass dish to prevent the falling of impurities, placed in a glass box, and the solvent was gradually evaporated to dryness at room temperature to form a film, and removed with tweezers to obtain a polyimide film (denoted as Co-CpODA-DENDA-0.8).
Through gas separation tests, the permeation coefficient of nitrogen is 53.1barrer, the permeation coefficient of oxygen is 178.5barrer, the permeation coefficient of hydrogen is 1456barrer, the permeation coefficient of methane is 156.4barrer, the permeation coefficient of carbon dioxide is 889.3barrer, the permeation selectivity of carbon dioxide/methane is 15.76, the permeation selectivity of carbon dioxide/nitrogen is 16.7, the temperature of 5% of thermal weight loss under the condition of nitrogen is 458 ℃, and the glass transition temperature is > 450 ℃.
Example 3
3.1 Synthesis of 1-Me-DMNDA monomer
(1) Freshly distilled methylcyclopentadiene (3.20 g,40 mmol) was added dropwise to an ice-cold solution of p-benzoquinone (2.16 g,20 mmol) in ethanol (20 mL) at 0deg.C under N2. The mixture was stirred at room temperature for 8 hours. The precipitate was collected by filtration, washed with cold ethanol and dried in vacuo to give 5.3g of product I as colourless in 99% yield.
(2) A solution of I (1.3411 g,5 mmol) in an ethyl acetate-ethanol (1:1) mixture (20 mL) containing 10% Pd/C (20 mg) was hydrogenated in a reactor apparatus with the addition of 2.5MPa hydrogen. After 8 hours, after natural cooling to room temperature, the insoluble catalyst was removed by suction filtration through a G-4 funnel and washed with dichloromethane (20 mL). The filtrate was concentrated under reduced pressure to filter, and the solid was dried in vacuo to give colorless crystalline solid II in quantitative yield (1.3 g).
(3) A solution of II (2.72 g,10 mmol) in chloroform (20 mL) was stirred at room temperature and a solution of Br2 (1.6 g,10 mmol) in chloroform (20 mL) was slowly added dropwise over 0.5 hour under an N2 atmosphere and the resulting suspension was stirred at room temperature for 8 hours. The resulting suspension was cooled in an ice-acetone bath for 1 hour and the precipitate was filtered under vacuum and washed with cold chloroform to give 98% brown solid III (2.7 g).
(4) III (9.460 g,35 mmol) was dissolved in acetic acid (300 ml) at 130℃and then aqueous potassium bromate (1.3%, 170 ml) was added, reacted for 2min, and immediately poured into 100ml of water. The reaction mixture was stirred for 30 minutes. The resulting suspension was cooled at room temperature, then filtered and washed with ethanol to give yellow product IV in 90% (8.45 g).
(5) Hydroxylamine hydrochloride (398.1 mg,5.73 mmol) was added to a solution of IV (18.785 g,70 mmol) in ethanol (250 ml, 95%) and the mixture was heated at 78℃for 2.5 hours, then cooled to room temperature and the solid was removed by filtration. The filtrate was poured into water (100 mL) and extracted with CH2Cl2 (3X 100 mL). The combined organic extracts were concentrated to give V (17.75 g) as a yellow solid in 85% yield.
(6) V (9.25 g,31 mmol), pd/C (1 g,10% Pd) and 160mL of ethanol were added to a 250mL vial under nitrogen and refluxed at 90℃and hydrazine hydrate (90 mL) was added using a syringe. After 12h of reaction, pd/C was removed by filtration through G4, the filtrate was concentrated by rotary evaporation, then poured into water to precipitate a solid, the white solid was collected by filtration, then washed with water and dried under vacuum at 100deg.C to give 1-Me-DMNDA (6.6G) as a white solid in 80% yield. (Nuclear magnetic hydrogen spectrogram is shown in figure 1 c)
3.2 polymerization of 1-Me-DMNDA diamine monomer
In this example, the structural formula of the polyimide based on 1-Me-DMNDA diamine is as follows:
3.2.1 in this example, the 6FDA-1-Me-DMNDA polyimide has the following structure:
into the flask, hexafluoroisopropyl phthalic anhydride (6 FDA) (1.110 g,2.5 mmol), 1-Me-DENDA (0.671 g,2.5 mmol), benzoic acid (0.1527 g,1.25 mmol) and m-cresol (6.6 g) were added under nitrogen atmosphere to control the solid content of the system to 20wt%. The reaction was continued for 8h at 80℃with mechanical stirring until complete dissolution of the reactants, increasing the temperature to 180℃and complete imidization of the polymer. M-cresol (24.40 g) was added, the solid content of the system was diluted to 5wt%, heating was stopped, and the temperature was naturally lowered to room temperature. The reaction solution was poured into a magnetically stirred ethanol and water mixture (300 ml, v/v=1:1), and a filiform white fibrous solid was precipitated and filtered. Placing the filamentous fiber solid into a Soxhlet extractor, heating and refluxing with ethanol for 18h, removing redundant m-cresol, and drying at 120 ℃ after the completion of the removal of the m-cresol to obtain polyimide containing a 1-Me-DMNDA structure.
The polyimide containing the dicyclo side group structure is dissolved in chloroform to prepare a solution with the solid content of 5wt%, insoluble substances and impurities are removed by filtration, air bubbles are eliminated by vacuumizing, and the polyimide solution is slowly poured onto a flat, smooth and dry glass surface dish by adopting a tape casting method. And (3) placing the glass surface dish into a film spreading oven, drying at room temperature for 12 hours, and completely soaking the glass plate in distilled water until the film naturally drops off to obtain the polyimide film (marked as 6 FDA-1-Me-DENDA) containing the double-ring side group structure.
The surface area was 472m by BET test 2 Per gram, measured by gas separation tests at 1barrer and 35 ℃, the permeability coefficient of nitrogen is 104.7barrer, the permeability coefficient of oxygen is 312.5barrer, the permeability coefficient of hydrogen is 1225barrer, the permeability coefficient of methane is 115.6barrer, the permeability coefficient of carbon dioxide is 1705barrer, the permeability selectivity of carbon dioxide/methane is 14.7, the permeability selectivity of carbon dioxide/nitrogen is 16.2, the temperature of 5% thermal weight loss under nitrogen condition is 421 ℃, and the glass transition temperature is 408 ℃.
3.2.2 in this example, co-BTA-1-Me-DMNDA-0.8 polyimide has the structure of the formula
Under the protection of nitrogen atmosphere, 0.2292g (0.516 mmol) 6FDA and 0.512g (2.064 mmol) BTA dianhydride and 0.6924g (2.58 mmol) DENDA and 0.1578g (1.29 mmol) benzoic acid are placed in a three-port polymerization bottle, then 6.6g anhydrous m-cresol solution is added to enable the solid content of the whole system to be 20wt%, after mechanical stirring is adjusted to a proper rotating speed, the system is heated to 80 ℃ for stirring for 1-2 h to enable the whole system to be dissolved, a transparent light yellow color solution is formed, after the solid is completely dissolved, the system is heated to 180 ℃ for thermal imidization, reaction is carried out for 8-10 h to enable polyimide to be completely thermal imidized, 10.5g m-cresol is added to enable the solid content of the system to be reduced to 9wt%, heating is turned off, cooling is carried out to 80 ℃, 300ml methanol is placed on a magnetic stirrer for stirring, the reaction solution is slowly placed in methanol to obtain white filamentous solid, the filamentous solid is placed on the magnetic stirrer for stirring for 2-3 h, the filamentous solid is filtered, the filamentous solid is placed on the magnetic stirrer for 12 ℃ for extracting, and then the polyimide is removed by a rope extraction, and the polyimide residue can be dried under the condition of vacuum, namely the polyimide is removed under the condition of 120 h.
The polymer (0.5 g) is dissolved in chloroform (25 ml) to prepare a solution with the solid content of 10 percent, the solution is fully stirred until the solution is completely dissolved, insoluble substances are filtered out by a filter head with the thickness of 0.45 mu m, a film is paved by a tape casting method, the film is paved on a clean glass dish, the film is uniformly shaken until no bubble exists, then the film is covered by a slightly bigger glass dish to prevent impurities from falling into the film, the film is placed in a glass box, the solvent is gradually evaporated to be dried and film-formed at room temperature, and a polyimide film (marked as Co-BTA-1-Me-DMNDA-0.8) is obtained after being taken down by tweezers.
Surface area of 489m by BET test 2 Per gram, measured by gas separation tests at 1barrer and 35 ℃, the permeability coefficient of nitrogen is 78.4barrer, the permeability coefficient of oxygen is 258.2barrer, the permeability coefficient of hydrogen is 1189barrer, the permeability coefficient of methane is 79.2barrer, the permeability coefficient of carbon dioxide is 1473barrer, the permeability selectivity of carbon dioxide/methane is 18.6, the permeability selectivity of carbon dioxide/nitrogen is 18.8, the temperature of 5% thermal weight loss under nitrogen is 426 ℃, and the glass transition temperature is 415 ℃.
Example 4
4.1 Synthesis of 4-Me-DMNDA monomer
(1) Rhenium methyltrioxide (1% mol,0.023 g) p-benzoquinone (0.5 g,4.625 mmol) was added at 0deg.C and N 2 Dissolved in ice-cold chloroform (10 mL) under an atmosphere, freshly distilled tetramethyl cyclopentadiene (1.74 mL,11.1 mmol) was slowly added dropwise to the mixed solution. The mixture was stirred at room temperature for 24 hours, the solution turned dark brown, the catalyst was removed by filtration, the filtrate was washed with chloroform and concentrated under reduced pressure to filter, the solid was dried in vacuo to give colorless 0.57g of product I in 70% yield.
(2) A solution of I (1.762 g,5 mmol) in a mixture of ethyl acetate-ethanol (1:1) containing 10% Pd/C (20 mg) (20 mL) was hydrogenated in a reactor apparatus with the addition of 2.5MPa hydrogen. After 8 hours, after natural cooling to room temperature, the insoluble catalyst was removed by suction filtration through a G-4 funnel and washed with dichloromethane (20 mL). The filtrate was concentrated under reduced pressure to filter, and the solid was dried in vacuo to give colorless crystalline solid II in quantitative yield (1.7 g).
(3) A solution of II (3.565 g,10 mmol) in chloroform (20 mL) was stirred at room temperature and a solution of Br2 (1.6 g,10 mmol) in chloroform (20 mL) was slowly added dropwise over 0.5 hour under an N2 atmosphere and the resulting suspension was stirred at room temperature for 8 hours. The resulting suspension was cooled in an ice-acetone bath for 1 hour and the precipitate was filtered under vacuum and washed with cold chloroform to give 98% yield of brown solid III (3.4 g).
(4) III (12.39 g,35 mmol) was dissolved in acetic acid (300 ml) at 130℃and then aqueous potassium bromate (1.3%, 170 ml) was added thereto, reacted for 2 minutes, and immediately poured into 100ml of water. The reaction mixture was stirred for 30 minutes. The resulting suspension was cooled at room temperature, then filtered and washed with ethanol to give yellow product IV in 90% (12.0 g).
(5) Hydroxylamine hydrochloride (398.1 mg,5.73 mmol) was added to a solution of IV (24.6 g,70 mmol) in ethanol (250 ml, 95%) and the mixture was heated at 78℃for 2.5 hours, then cooled to room temperature and the solids removed by filtration. The filtrate was poured into water (100 mL) and extracted with CH2Cl2 (3X 100 mL). The combined organic extracts were concentrated to give V (22.75 g) as a yellow solid in 85% yield.
(6) V (11.859 g,31 mmol), pd/C (1 g,10% Pd) and 160mL of ethanol were added to a 250mL vial under nitrogen, refluxed at 90℃and hydrazine hydrate (90 mL) was added using a syringe. After 12h of reaction, pd/C was removed by filtration through G4, the filtrate was concentrated by rotary evaporation, then poured into water to precipitate a solid, the white solid was collected by filtration, then washed with water and dried under vacuum at 100deg.C to give 1-Me-DMNDA (7.6G) as a white solid in 70% yield. (Nuclear magnetic hydrogen spectrogram is shown in figure 1 d)
2.2 polymerization of 4-Me-DMNDA diamine monomer
In this example, the structural formula of the polyimide based on 4-Me-DMNDA diamine is as follows:
4.2.1 in this example, the 6FDA-4-Me-DMNDA polyimide has the following structure:
into the flask, hexafluoroisopropyl phthalic anhydride (6 FDA) (1.110 g,2.5 mmol), 4-Me-DMNDA (0.881 g,2.5 mmol), benzoic acid (0.1527 g,1.25 mmol) and m-cresol (6.9 g) were added under nitrogen atmosphere to control the solid content of the system to 20wt%. The reaction was continued for 8h at 80℃with mechanical stirring until complete dissolution of the reactants, increasing the temperature to 180℃and complete imidization of the polymer. M-cresol (24.40 g) was added, the solid content of the system was diluted to 5wt%, heating was stopped, and the temperature was naturally lowered to room temperature. The reaction solution was poured into a magnetically stirred ethanol and water mixture (300 ml, v/v=1:1), and a filiform white fibrous solid was precipitated and filtered. Placing the filamentous fiber solid into a Soxhlet extractor, heating and refluxing with ethanol for 18h, removing redundant m-cresol, and drying at 120 ℃ after the completion of the removal of the m-cresol to obtain polyimide containing a 4-Me-DMNDA structure.
The polyimide containing the dicyclo side group structure is dissolved in chloroform to prepare a solution with the solid content of 5wt%, insoluble substances and impurities are removed by filtration, air bubbles are eliminated by vacuumizing, and the polyimide solution is slowly poured onto a flat, smooth and dry glass surface dish by adopting a tape casting method. And (3) placing the glass surface dish into a film spreading oven, drying at room temperature for 12 hours, and completely soaking the glass plate in distilled water until the film naturally drops off, thus obtaining the polyimide film (marked as 6 FDA-4-Me-DMNDA) containing the double-ring side group structure.
The permeation coefficient of nitrogen was 105.3 barrers, the permeation coefficient of oxygen was 318.7 barrers, the permeation coefficient of hydrogen was 1308 barrers, the permeation coefficient of methane was 128.5 barrers, the permeation coefficient of carbon dioxide was 1758 barrers, the permeation selectivity of carbon dioxide/methane was 13.7, the permeation selectivity of carbon dioxide/nitrogen was 16.7, the temperature of 5% thermal weight loss under nitrogen was 418 ℃ and the glass transition temperature was 425 ℃ as measured by gas separation tests at 1barrer and 35 ℃.
4.2.2 in this example, co-CpODA-4-Me-DMNDA-0.8 polyimide had the structure of the formula
The preparation of the polyimide gas separation membrane mainly comprises the following steps:
under the protection of nitrogen atmosphere, 0.2292g (0.516 mmol) of 6FDA and 0.7933g (2.064 mmol) of CpODA dianhydride and 0.9096g (2.58 mmol) of 4-Me-DMNDA and 0.1578g (1.29 mmol) of benzoic acid are placed in a three-port polymerization bottle, 7.6g of anhydrous m-cresol solution is added to enable the solid content of the whole system to be 20wt%, after mechanical stirring is adjusted to a proper rotating speed, the system is heated to 80 ℃ for stirring for 1-2 h to enable the whole system to be dissolved, a transparent light yellow solution is formed, after the solid is completely dissolved, the system is heated to 180 ℃ for thermal imidization, the polyimide is reacted for 8-10 h to enable the solid content of the system to be reduced to 9wt%, the heating is turned off, the heating is reduced to 80 ℃, 300ml of methanol is placed on a magnetic stirrer for stirring, the reaction solution is slowly poured into the methanol to obtain a white fibrous solid, the filiform solid is placed on the magnetic stirrer for stirring for 2-3 h, the filiform solid is filtered, the filiform solid is placed on a rope for extraction rope at 12 ℃ for extraction, and the filiform solvent is removed under the condition, namely the filiform polyimide is dried under the condition of 120 h, and the filiform solvent is removed under the condition.
The polymer (0.5 g) is dissolved in chloroform (25 ml) to prepare a solution with the solid content of 10 percent, the solution is fully stirred until the solution is completely dissolved, insoluble substances are filtered out by a filter head with the thickness of 0.45 mu m, a film is paved by a tape casting method, the film is paved on a clean glass dish, the film is uniformly shaken until no bubble exists, then the film is covered by a slightly bigger glass dish to prevent impurities from falling into the film, the film is placed in a glass box, the solvent is gradually evaporated to be dried and film-formed at room temperature, and a polyimide film (marked as Co-CpODA-4-Me-DMNDA-0.8) is obtained after being taken down by tweezers.
Through the gas separation test, the permeation coefficient of nitrogen was 54.8barrer, the permeation coefficient of oxygen was 1.84.3 barrer, the permeation coefficient of hydrogen was 769.4barrer, the permeation coefficient of methane was 56.7barrer, the permeation coefficient of carbon dioxide was 929.7barrer, the permeation selectivity of carbon dioxide/methane was 16.4, the permeation selectivity of carbon dioxide/nitrogen was 16.9, the temperature of 5% thermal weight loss under nitrogen was 426 ℃ and the glass transition temperature was 408 ℃.
Example 5
5.1 Synthesis of 5-Me-DMNDA monomer
(1) Methyl rhenium trioxide (1% mol,0.046 g) p-benzoquinone (1.0 g,9.25 mmol) was dissolved in ice-cold chloroform (20 mL) at 0deg.C under N2 atmosphere, and freshly distilled tetramethyl cyclopentadiene (3.6 mL,22.2 mmol) was slowly added dropwise to the mixed solution. The mixture was stirred at room temperature for 24 hours, the solution turned dark brown, the catalyst was removed by filtration, the filtrate was washed with chloroform and concentrated under reduced pressure to filter, the solid was dried in vacuo to give 2.6g of product I as colorless in 75% yield.
(2) A solution of I (1.91 g,5 mmol) in an ethyl acetate-ethanol (1:1) mixture (20 mL) containing 10% Pd/C (20 mg) was hydrogenated in a reactor apparatus with the addition of 2.5MPa hydrogen. After 8 hours, after natural cooling to room temperature, the insoluble catalyst was removed by suction filtration through a G-4 funnel and washed with dichloromethane (20 mL). The filtrate was concentrated under reduced pressure to filter, and the solid was dried in vacuo to give colorless crystalline solid II in 90% (1.7 g).
(3) A solution of II (3.846 g,10 mmol) in chloroform (20 mL) was stirred at room temperature and at N 2 A solution of Br2 (1.6 g,10 mmol) in chloroform (20 mL) was slowly added dropwise over 0.5 hour under an atmosphere, and the resulting suspension was stirred at room temperature for 8 hours. The resulting suspension was cooled in an ice-acetone bath for 1 hour and the precipitate was filtered under vacuum and washed with cold chloroform to give III (3.4 g) as a 90% brown solid.
(4) III (13.39 g,35 mmol) was dissolved in acetic acid (300 ml) at 130℃and then aqueous potassium bromate (1.3%, 170 ml) was added thereto, reacted for 2 minutes, and immediately poured into 100ml of water. The reaction mixture was stirred for 30 minutes. The resulting suspension was cooled at room temperature, then filtered and washed with ethanol to give yellow product IV in 80% (10.65 g).
(5) Hydroxylamine hydrochloride (398.1 mg,5.73 mmol) was added to a solution of IV (26.6 g,70 mmol) in ethanol (250 ml, 95%) and the mixture was heated at 78℃for 2.5 hours, then cooled to room temperature and the solids removed by filtration. The filtrate was poured into water (100 mL) and extracted with CH2Cl2 (3X 100 mL). The combined organic extracts were concentrated to give V (22.9 g) as an earthy yellow solid in 80% yield.
(6) V (12.71 g,31 mmol), pd/C (1 g,10% Pd) and 160mL of ethanol were added to a 250mL vial under nitrogen and refluxed at 90℃and hydrazine hydrate (90 mL) was added using a syringe. After 12h of reaction, pd/C was removed by filtration through G4, the filtrate was concentrated by rotary evaporation, then poured into water to precipitate a solid, the white solid was collected by filtration, then washed with water and dried under vacuum at 100deg.C to give 5-Me-DMNDA (8.83G) as a white solid in 75% yield.
5.2 polymerization of 5-Me-DMNDA diamine monomer
In this example, the polyimide based on 5-Me-DMNDA diamine has the following structural formula:
5.2.1 in this example, the 6FDA-5-Me-DMNDA-0.8 polyimide has the structure of the formula:
into the flask, hexafluoroisopropyl phthalic anhydride (6 FDA) (1.110 g,2.5 mmol), 5-Me-DENDA (0.951 g,2.5 mmol), benzoic acid (0.1527 g,1.25 mmol) and m-cresol (7.1 g) were added under nitrogen atmosphere to control the solid content of the system to 20wt%. The reaction was continued for 8h at 80℃with mechanical stirring until complete dissolution of the reactants, increasing the temperature to 180℃and complete imidization of the polymer. M-cresol (24.40 g) was added, the solid content of the system was diluted to 5wt%, heating was stopped, and the temperature was naturally lowered to room temperature. The reaction solution was poured into a magnetically stirred ethanol and water mixture (300 ml, v/v=1:1), and a filiform white fibrous solid was precipitated and filtered. Placing the filamentous fiber solid into a Soxhlet extractor, heating and refluxing with ethanol for 18h, removing redundant m-cresol, and drying at 120 ℃ after the completion of the removal of the m-cresol to obtain polyimide containing a 5-Me-DMNDA structure.
The polyimide containing the dicyclo side group structure is dissolved in chloroform to prepare a solution with the solid content of 5wt%, insoluble substances and impurities are removed by filtration, air bubbles are eliminated by vacuumizing, and the polyimide solution is slowly poured onto a flat, smooth and dry glass surface dish by adopting a tape casting method. And (3) placing the glass surface dish into a film spreading oven, drying at room temperature for 12 hours, and completely soaking the glass plate in distilled water until the film naturally drops off, thus obtaining the polyimide film (marked as 6 FDA-5-Me-DENDA) with the double-ring side group structure.
Through gas separation tests, the permeation coefficient of nitrogen is 116.5barrer, the permeation coefficient of oxygen is 325barrer, the permeation coefficient of hydrogen is 1311barrer, the permeation coefficient of methane is 131barrer, the permeation coefficient of carbon dioxide is 1764barrer, the permeation selectivity of hydrogen/methane is 10, the permeation selectivity of hydrogen/nitrogen is 11.2, the temperature of 5% thermal weight loss under the condition of nitrogen is 442 ℃, and the glass transition temperature is > 450 ℃.
5.2.2 in this example, co-BTA-5-Me-DMNDA-0.8 polyimide has the structure of the formula
Under the protection of nitrogen atmosphere, 0.2292g (0.516 mmol) 6FDA and 0.512g (2.064 mmol) BTA dianhydride and 0.9819g (2.58 mmol) DENDA and 0.1578g (1.29 mmol) benzoic acid are placed in a three-port polymerization bottle, then 6.6g anhydrous m-cresol solution is added to enable the solid content of the whole system to be 20wt%, after mechanical stirring is adjusted to a proper rotating speed, the system is heated to 80 ℃ for stirring for 1-2 h to enable the whole system to be dissolved, a transparent light yellow color solution is formed, after the solid is completely dissolved, the system is heated to 180 ℃ for thermal imidization, reaction is carried out for 8-10 h to enable polyimide to be completely thermal imidized, 10.5g m-cresol is added to enable the solid content of the system to be reduced to 9wt%, heating is turned off, cooling is carried out to 80 ℃, 300ml methanol is placed on a magnetic stirrer for stirring, the reaction solution is slowly placed in methanol to obtain white filamentous solid, the filamentous solid is placed on the magnetic stirrer for stirring for 2-3 h, the filamentous solid is filtered, the filamentous solid is placed on the magnetic stirrer for 12 ℃ for extracting, and then the polyimide is removed by a rope extraction, and the polyimide residue can be dried under the condition of vacuum, namely the polyimide is removed under the condition of 120 h.
The above polymer (0.5 g) was dissolved in chloroform (25 ml) to prepare a solution with a solid content of 10%, stirred sufficiently until the solution was completely dissolved, insoluble matters were filtered off with a 0.45 μm filter head, film-laid by casting, spread on a clean glass dish, shaken uniformly until no bubbles were formed, covered with a slightly larger glass dish to prevent the falling of impurities, placed in a glass box, and the solvent was gradually evaporated to dryness at room temperature to form a film, and removed with tweezers to obtain a polyimide film (denoted as Co-BTA-5-Me-DMNDA-0.8).
Through gas separation tests, the permeation coefficient of nitrogen is 82.5 barrers, the permeation coefficient of oxygen is 264.2 barrers, the permeation coefficient of hydrogen is 1251 barrers, the permeation coefficient of methane is 80.1 barrers, the permeation coefficient of carbon dioxide is 1651 barrers, the permeation selectivity of hydrogen/methane is 15.6, the permeation selectivity of hydrogen/nitrogen is 15.1, the temperature of 5% of thermal weight loss under nitrogen condition is 432 ℃, and the glass transition temperature is > 450 ℃.
The performance test methods involved in the examples are as follows:
(1) Structural characterization:
the nuclear magnetism of the polyimide film containing the dicyclo side group structure is tested by using a Bruce nuclear magnetic resonance instrument;
The infrared of the polyimide film containing the dicyclo side group structure is tested by using a Fourier transform attenuated total reflection infrared spectrometer.
(2) Physical property test:
the specific surface area of the polyimide film containing the dicyclo side group structure is tested by grinding polyimide into powder by using a microphone ASAP2640 full-automatic specific surface area and porosity analyzer;
the inter-segment distance d of the polyimide film containing the dicyclo side group structure is tested by adopting an X-ray diffraction analyzer Ultima IV (Rigaku);
the density of the polyimide film containing the dicyclo side group structure is tested by adopting an analytical balance Sartorius SQP (density component YDK 03) and taking isooctane as a medium solvent at room temperature.
(3) Gas separation performance test:
the polyimide film containing the dicyclic side group structure has the following characteristics that the polyimide film contains two or more groups of polyimide films 2 、O 2 、N 2 、CH 4 、CO 2 ) Is tested using a gas permeameter at 35 c and 1 Barrer.
TABLE 1 gas permeation coefficient and selection coefficient data
TABLE 2 dissolution performance data for DMNDA diamine-based polymers
TABLE 3 thermodynamic properties of DMNDA diamine-based polymers
TABLE 4 physical Property data for DMNDA diamine-based polymers
Characterization of the properties:
FIG. 3 is a graph of the ultraviolet-visible spectrum of a polyimide film having a dicyclic pendant structure prepared in example 1 of the present invention; FIGS. 4 a-4 c show the polyimide films containing bicyclic pendant structures of examples 1, 2, 5 of the present invention, and the pairs of seven commercial gas separation membranes of the prior art, hexafluorodianhydride, H 2 /CH 4 Is a gas separation performance graph of (1); FIGS. 5 a-5 c show the polyimide films containing bicyclic pendant structures of examples 1, 2, 5 of the present invention, and the pairs of seven commercial gas separation membranes of the prior art, hexafluorodianhydride, H 2 /N 2 Is a gas separation performance graph of (a). Table 1 shows the gas permeation coefficients and selectivity coefficients of typical examples 1, 2 and 5 of the present invention, and the reported hexafluorodianhydride, seven commercial gas separation membranes, as can be seen from the table: examples 1, 2, 5 for five single gases (H 2 、O 2 、N 2 、CH 4 、CO 2 ) Has higher permeability coefficients than the corresponding hexafluorodianhydridePolyimide polymers (references: polymer 2019, 161, 16-26; polymer 2017, 130, 182-190;Macromolecular Rapid Communications 2011, 32 (7), 579-86;Chemistry of Materials2019, 31 (5), 1767-1774) and commercial gas separation membranes (references: journal of Membrane Science2008, 314 (1-2), 123-133;Journal of Applied Polymer Science 2010, 101 (6), 3800-3805;Progress in Polymer Science 1988, 13 (4), 339-401;Journal of Polymer Science Part B:Polymer Physics 1987, 25 (9), 1999-2026;Journal of Membrane Science1998, 138 (2), 143-152), the permeability coefficients of some embodiments of the gas separation efficiency are greatly improved, the hydrogen/methane, hydrogen/nitrogen performance of some embodiments is near the upper limit of Robeson in 2008, and the method has good application prospects in industrial hydrogen purification and recovery applications.
Table 2 shows the solubilities of four polyimides prepared using DMNDA diamine monomer as an example. The solubility of 6FDA-DMNDA polyimide is superior to other polyimides, which may be associated with less rigid hexafluoroisopropyl units. All polymers showed good solubility. GPC measurement with DMF as mobile phase gave a weight average molecular weight of 62-105kg mol as shown in Table 3 -1 The four DMNDA-based polymer films have good mechanical properties, and the tensile strength of the four DMNDA-based polymer films is between 48 and 70 MPa; young's modulus between 1.48 and 2.19 GPa; the elongation at break is between 3.46 and 10.89 percent, which is equivalent to the reported mechanical properties of PIM-PIs. The thermal properties of the polymers were determined by thermogravimetric analysis (TGA) and Dynamic Mechanical Analysis (DMA). Thermal weight loss temperature (T) of the synthesized polyimide 5％ ) The presence of bicyclic side groups reduces the thermal stability of the polymer at temperatures between 446 and 454℃and glass transition temperatures (Tg) between 319 and 423 ℃.
Table 4 shows the gas adsorption and microporous properties of the polymer, and the BET specific surface area of the synthesized polymer is 469-631m 2 g -1 In addition, the specific surface area of the SBI-DMNDA polymer is the largest, and the SBI sites with rigidity and large volume distortion are additionally introduced, so that the stacking of polymer molecular chains can be effectively blocked, and the polymer has high specific surface area. At the same time, the polymer is at P Total pore volume at 0.276-0.478cm for/p0=0.95 3 g -1 The DFT method is used for calculating the pore size distribution between 0 and 2nm, and the pore size distribution has micropores and ultramicropores. The microporous structure of the polymer was determined by wide angle X-ray diffraction (WAXD), and the d value calculated according to the Bragg equation represents the distance between molecular chains, and the free volume fraction (FFV) calculated according to the film density, which is between 0.623 and 0.216, is between SBI-DMNDA > 6FDA-DMNDA > co-BTA-DMNDA > co-CpODA-DMNDA. This is consistent with the results of WAXD. In addition, the inventors have conducted experiments with other materials, process operations, and process conditions as described in this specification with reference to the foregoing examples, and have all obtained desirable results.
It should be understood that the technical solution of the present invention is not limited to the above specific embodiments, and all technical modifications made according to the technical solution of the present invention without departing from the spirit of the present invention and the scope of the claims are within the scope of the present invention.
Claims (10)
1. A diamine monomer having a bicyclic pendant structure, wherein the diamine monomer has a structure as shown in any one of formulas (I) - (V):
2. The method for producing a diamine monomer having a bicyclolated side group structure as claimed in claim 1, comprising:
making benzoquinone and diene compound undergo the processes of D-A reaction, reduction, substitution, oxidation, esterification, substitution and oximation reaction in turn so as to obtain diamine monomer containing dicyclo side group structure;
wherein the diene compound comprises any one or more than two of cyclopentadiene, cyclohexadiene, methyl cyclopentadiene, tetramethyl cyclopentadiene and pentamethyl cyclopentadiene.
3. A polyimide film, characterized in that: the polyimide film is prepared from polyimide containing a dicyclo side group structure, the polyimide containing the dicyclo side group structure is prepared from the diamine monomer containing the dicyclo side group structure as shown in the claim 1, and the polyimide has a structure shown in a formula (VI):
wherein n is more than 1 and less than 1000, R 1 A structure selected from the group consisting of any one or a combination of two or more of the following formulas:
R 2 a structure selected from any one of the following formulas:
wherein the dashed line represents the key-in position.
4. A polyimide film according to claim 3, characterized in that: the polyimide film has a thermal decomposition temperature of more than 400 ℃ when losing weight of 5wt% under the nitrogen atmosphere; the specific surface area of the polyimide film is 100m 2 /g or more;
and/or the thickness of the polyimide film is 50-80 mu m.
5. The method for producing a polyimide film according to claim 3 or 4, comprising:
providing a diamine monomer containing a bicyclic pendant group structure of claim 1;
reacting a mixed reaction system comprising the diamine monomer, the aromatic dianhydride, the catalyst and the solvent for 1-4 hours at 50-100 ℃ in a protective atmosphere to prepare a prepolymer;
heating the prepolymer to 140-200 ℃, and continuing to react for 4-12 hours to prepare polyimide containing a dicyclo side group structure;
and mixing the polyimide containing the dicyclo side group structure with an organic solvent and performing film laying treatment to obtain the polyimide film.
6. The method of manufacturing according to claim 5, wherein: the aromatic dianhydride comprises hexafluoroisopropyl phthalic anhydride, 3',4' -benzophenone tetracarboxylic dianhydride, 3',4' -biphenyl tetracarboxylic dianhydride, 2, 3',4' -biphenyltetracarboxylic dianhydride, 4' -biphenyldianhydride, 9-bis (3, 4-dicarboxyphenyl) fluorene dianhydride, 3, 4-diphenylalum tetracarboxylic dianhydride, 1,4,5, 8-tea tetracarboxylic anhydride 9, 9-bis (trispeamethyl) -2,3,6, 7-oxa-tetracarboxyl dianhydride, pyromellitic dianhydride, bicyclo [2.2.2] oct-7-ene-2, 3,5, 6-tetracarboxylic dianhydride, norbornane-2-spiro-alpha-cycloalkanone-alpha ' -spiro-2 ' -norbornane-5, 5 ', 6,6 ' -tetracarboxylic dianhydride, 3' -tetramethyl 2,2',3,3' -tetrahydro-1, 1-spirobiindene tetracarboxylic dianhydride, 7' -spirobiindene [ 7H-cyclopentadiene [ g ] isobenzofuran [5,6-b ] [1,4] benzodioxin ] -1,1', any one or the combination of more than two of 3,3' -tetralone, 8', 9' -tetrahydro-9,9,9 ',9' -tetramethyl tetracarboxylic dianhydride;
And/or the catalyst comprises a basic catalyst and/or an acidic catalyst, wherein the acidic catalyst comprises benzoic acid and/or parahydroxybenzoic acid; the basic catalyst comprises any one or more than two of triethylamine, tripropylamine, tributylamine and isoquinoline, preferably isoquinoline and/or triethylamine;
and/or the solvent comprises any one or more than two of m-cresol, p-chlorophenol, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone.
7. The method of manufacturing according to claim 5, wherein: the molar ratio of the diamine monomer, the aromatic dianhydride and the catalyst is 1:1:0.5-3.
8. The method for preparing as claimed in claim 5, further comprising: after the prepolymer reaction is completed, adding a precipitant into the obtained mixture, and then carrying out a Soxhlet extraction treatment; preferably, the precipitating agent comprises any one or more of methanol, ethanol, acetone, petroleum ether and water.
9. The method of claim 5, wherein the film laying process comprises: mixing polyimide containing a dicyclo side group structure with an organic solvent to form a solution with the mass fraction of 1-10%, spreading a film on a substrate by adopting a tape casting method, and then performing temperature programming treatment, drying and demolding treatment; preferably, the organic solvent comprises any one or more than two of tetrahydrofuran, dichloromethane, chloroform, m-cresol, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone; preferably, the temperature of the drying treatment is 50-100 ℃ and the drying time is 6-20 h; preferably, the temperature programming process includes: the room temperature is raised to 60-80 ℃ for heat preservation for 6-10 h, then is raised to 80-120 ℃ for heat preservation for 2-5h, then is raised to 120-150 ℃ for heat preservation for 3-6h, and finally is raised to 200-300 ℃ for heat preservation for 2-5h.
10. Use of the polyimide film according to claim 3 or 4 in the field of gas separation, preferably in the separation of hydrogen, methane, carbon dioxide or oxygen.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310024226.4A CN116023277A (en) | 2023-01-05 | 2023-01-05 | Diamine monomer containing dicyclo side group structure, and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310024226.4A CN116023277A (en) | 2023-01-05 | 2023-01-05 | Diamine monomer containing dicyclo side group structure, and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116023277A true CN116023277A (en) | 2023-04-28 |
Family
ID=86070947
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310024226.4A Pending CN116023277A (en) | 2023-01-05 | 2023-01-05 | Diamine monomer containing dicyclo side group structure, and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116023277A (en) |
-
2023
- 2023-01-05 CN CN202310024226.4A patent/CN116023277A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112275147B (en) | Self-polymerization microporous polyimide gas separation membrane and preparation method and application thereof | |
| Terraza et al. | Synthesis and properties of new aromatic polyimides containing spirocyclic structures | |
| CN110787663B (en) | High permeability polymer composite membrane for gas separation and method of making the same | |
| US20200165189A1 (en) | Pseudo tröger's base amines and microporous polymers derived from pseudo tröger's base amines | |
| WO2011129769A1 (en) | Polyimide membranes and their preparation | |
| Hu et al. | Synthesis and gas separation performances of intrinsically microporous polyimides based on 4-methylcatechol-derived monomers | |
| CN109053474B (en) | Flexible diamine monomer, preparation method thereof and application thereof in preparation of polyimide | |
| KR101552517B1 (en) | Crosslinked thermally rearranged poly(benzoxazole-co-imide), gas separation membranes comprising the same and preparation method thereof | |
| Chen et al. | Synthesis, characterization and properties of polyimides with spirobisbenzoxazole scaffold structure | |
| US20200199348A1 (en) | Bcda-based semi-alicyclic homo- or co-polyimide membrane materials for gas separation and the preparation method thereof | |
| CN116023277A (en) | Diamine monomer containing dicyclo side group structure, and preparation method and application thereof | |
| CN114591503B (en) | Soluble poly (benzimidazole-co-imide) polymer and preparation and application thereof | |
| CN115477757B (en) | Thermal rearrangement polymer based on 2,2', 3' -biphenyl tetracarboxylic dianhydride, and preparation method and application thereof | |
| CN114716676A (en) | Application of polyimide in gas separation membrane | |
| CN113244788A (en) | Synthetic method and application of polyimide gas separation membrane material | |
| CN115612101B (en) | Thermal rearrangement polybenzoxazole film and preparation method and application thereof | |
| KR101572512B1 (en) | Method for preparation of crosslinked thermally rearranged poly(benzoxazole-co-imide) membranes for flue gas separation and membranes for flue gas separation prepared thereby | |
| CN108976135B (en) | Flexible diamine monomer, preparation method thereof and application thereof in preparation of polyimide | |
| KR101404160B1 (en) | Polymer, method of preparing the same, and article including the polymer | |
| CN112876678A (en) | Soluble polyimide containing hexamethyl substitution structure and preparation method and application thereof | |
| KR101389543B1 (en) | Preparation method of polybenzimidazole | |
| CN116440721A (en) | Triptycene unit polyimide film for gas separation and preparation method thereof | |
| CN113372554B (en) | Semi-alicyclic polyimide and application of film thereof in gas separation | |
| JP2001040089A (en) | Polyimide resin, its production and gas separation membrane composed thereof | |
| CN111233842B (en) | Phthalazinone diamine monomer and preparation method thereof, polyimide and preparation method thereof, and polyimide film |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |