GB2244997A - Copolyimides for use as gas separation membranes - Google Patents
Copolyimides for use as gas separation membranes Download PDFInfo
- Publication number
- GB2244997A GB2244997A GB9111107A GB9111107A GB2244997A GB 2244997 A GB2244997 A GB 2244997A GB 9111107 A GB9111107 A GB 9111107A GB 9111107 A GB9111107 A GB 9111107A GB 2244997 A GB2244997 A GB 2244997A
- Authority
- GB
- United Kingdom
- Prior art keywords
- copolyimide
- solvent
- membrane
- gas separation
- dissolving
- 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.)
- Withdrawn
Links
- 239000012528 membrane Substances 0.000 title claims abstract description 17
- 238000000926 separation method Methods 0.000 title claims abstract description 11
- 239000002904 solvent Substances 0.000 claims abstract description 12
- 150000004985 diamines Chemical class 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims abstract description 7
- 239000000758 substrate Substances 0.000 claims abstract description 6
- 239000000376 reactant Substances 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 7
- 125000006159 dianhydride group Chemical group 0.000 claims description 3
- GTDPSWPPOUPBNX-UHFFFAOYSA-N ac1mqpva Chemical compound CC12C(=O)OC(=O)C1(C)C1(C)C2(C)C(=O)OC1=O GTDPSWPPOUPBNX-UHFFFAOYSA-N 0.000 abstract description 6
- OMHOXRVODFQGCA-UHFFFAOYSA-N 4-[(4-amino-3,5-dimethylphenyl)methyl]-2,6-dimethylaniline Chemical compound CC1=C(N)C(C)=CC(CC=2C=C(C)C(N)=C(C)C=2)=C1 OMHOXRVODFQGCA-UHFFFAOYSA-N 0.000 abstract description 3
- 238000001471 micro-filtration Methods 0.000 abstract description 2
- 230000005855 radiation Effects 0.000 abstract description 2
- 238000000108 ultra-filtration Methods 0.000 abstract description 2
- 230000035699 permeability Effects 0.000 description 13
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 9
- 239000007789 gas Substances 0.000 description 9
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 8
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 6
- 239000004642 Polyimide Substances 0.000 description 6
- 229920001721 polyimide Polymers 0.000 description 6
- 229920000642 polymer Polymers 0.000 description 5
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 4
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 3
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- VQVIHDPBMFABCQ-UHFFFAOYSA-N 5-(1,3-dioxo-2-benzofuran-5-carbonyl)-2-benzofuran-1,3-dione Chemical compound C1=C2C(=O)OC(=O)C2=CC(C(C=2C=C3C(=O)OC(=O)C3=CC=2)=O)=C1 VQVIHDPBMFABCQ-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 229940113088 dimethylacetamide Drugs 0.000 description 2
- -1 diohloromethane Chemical compound 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 description 2
- JZODKRWQWUWGCD-UHFFFAOYSA-N 2,5-di-tert-butylbenzene-1,4-diol Chemical compound CC(C)(C)C1=CC(O)=C(C(C)(C)C)C=C1O JZODKRWQWUWGCD-UHFFFAOYSA-N 0.000 description 1
- XVMKZAAFVWXIII-UHFFFAOYSA-N 5-fluoro-2-benzofuran-1,3-dione Chemical compound FC1=CC=C2C(=O)OC(=O)C2=C1 XVMKZAAFVWXIII-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- MHABMANUFPZXEB-UHFFFAOYSA-N O-demethyl-aloesaponarin I Natural products O=C1C2=CC=CC(O)=C2C(=O)C2=C1C=C(O)C(C(O)=O)=C2C MHABMANUFPZXEB-UHFFFAOYSA-N 0.000 description 1
- 239000004697 Polyetherimide Substances 0.000 description 1
- 229920004747 ULTEM® 1000 Polymers 0.000 description 1
- 150000008064 anhydrides Chemical class 0.000 description 1
- 229920006037 cross link polymer Polymers 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000004128 high performance liquid chromatography Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 238000000614 phase inversion technique Methods 0.000 description 1
- 229920005575 poly(amic acid) Polymers 0.000 description 1
- 229920001601 polyetherimide Polymers 0.000 description 1
- 235000003270 potassium fluoride Nutrition 0.000 description 1
- 239000011698 potassium fluoride Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000011369 resultant mixture Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000000935 solvent evaporation Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 238000009281 ultraviolet germicidal irradiation Methods 0.000 description 1
- 238000010626 work up procedure Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/58—Other polymers having nitrogen in the main chain, with or without oxygen or carbon only
- B01D71/62—Polycondensates having nitrogen-containing heterocyclic rings in the main chain
- B01D71/64—Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G73/1042—Copolyimides derived from at least two different tetracarboxylic compounds or two different diamino compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G73/1046—Polyimides containing oxygen in the form of ether bonds in the main chain
- C08G73/1053—Polyimides containing oxygen in the form of ether bonds in the main chain with oxygen only in the tetracarboxylic moiety
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
A copolyimide is prepared by dissolving 3,3',5,5'-tetramethyl-4,4'-diaminodiphenyl-methane in a solvent, (b) adding to the diamine solution a mixture of 1,4-bis-(3,4-dicarbophenoxy)-2,5-di-tertiary-butylbenzene dianhydride and 3,3',4,4'-bensophenonetetracarboxylic dianhydride in a weight percent ratio from 20:1 to 1:1, and (c) allowing the reactant to polymerise. Membranes, suitable for gas separations and micro- and ultra-filtration applications, may be prepared by dissolving the copolyimide in a solvent, spreading the resultant solution onto a substrate, allowing the solvent to evaporate and subsequently removing the membrane from the substrate. The membrane may be crosslinked with UV radiation.
Description
POLYMER SYNTHESIS
The present invention relates to novel polyimides and in particular to methods of synthesis of crosslinked aromatic polyimides suitable for use as gas separation membranes.
It is known to synthesise aromatic polyimides by reaction of dianhydrides with diamines and to cast a gas separation membrane from the polyimide. However membranes prepared by known processes are limited in gas separation applications by lack of either sufficient selectivity or permeability. The present invention relates to a novel polyimide, its preparation and the method of forming membranes from the polyimide which have improved selectivities and permeabilities.
Thus according to the present invention there is provided a copolyimide comprising 95-50% of structural repeating unit A and 5-50% of structural repeating unit B.
According to a further aspect of the invention there is provided a method of synthesising a copolyimide (as hereinabove described) comprising the steps of (a) dissolving TM diamine in a suitable solvent (b) adding to the diamine solution a mixture of
BHDA and BTDA dianhydrides in a weight percent ratio from 20 to 1 and (c) allowing the reactants to polymerise where:
TM is
BHDA is
and BTDA is
According to a further aspect of the invention there is provided a method of forming a gas separation membrane from a copolyimide (as hereinabove described) comprising the steps of dissolving the copolyimide in a solvent, spreading the resultant solution onto a substrate, allowing the solvent to evaporate to form a membrane on the substrate and subsequently removing the membrane.
Suitable solvents include chloroform, diohloromethane, tetrahydrofuran, n-methylpyrolidone (NMP), dimethylformamide (DMF), dimethylacetamide. The weight percent of polymer in the solvent is preferably in the range 1-5%.
It is also envisaged that the gas separation membrane can also be produced by use of the phase inversion technique, thereby producing asymmetric gas separation membranes.
The invention will now be described by way of example only.
Dense films were cast from a 3 wt % solution of the above polymer in chloroform. After solvent evaporation the films were annealed at 2000C for 3 days. The films were then tested for pure gas (02, N2, CH4, H2) permeabilities at 35"C and 6.5 bar (6.5 x 105 Pa), with the following results:
02 permeability 9.28 Barrer
N2 permeability 1.89 Barrer
02/N2 selectivity 4.9
CH4 permeability 1.81 Barrer
H2 permeability 81.8 Barrer
H2/CH4 selectivity 45
The above films were then exposed to the UV radiation from a
Hanovia 500 watt medium pressure mercury arc lamp (film 11 cm from lamp) for 20 minutes at 25 C, on one side. After UV irradiation, the films became insoluble in chloroform, dichloromethane or n-methyl pyrrolidone (NMP), good solvents for the uncrosslinked polymer.
The above irradiated films were tested for pure gas permeabilities, with the following results: 2 permeability 3.40 Barrer
N2 permeability 0.265 Barrer
02/N2 selectivity 13
H2 permeability 74.8 Barrer
CH4 permeability 0.115 Barrer
H2/CH4 selectivity 650
Although the ratio of BHDA:BTDA used in the above example was 80:20, this ratio may be varied, the Z BTDA being say 5 to 50%.
The oxygen/nitrogen separation characteristics of the UV crosslinked polymer are very good and compare well with the commercially available polyetherimide Ultem 1000 (General Electric) having O2/N2 selectivities of the order 7 and oxygen permeabilities of 0.5 Barrer.
The copolyimide was synthesised as follows: 2.54 g (0.01 mole) of 3,3',5,5'-tetramethyl-4,4'- diaminodiphenylmethane (development product from Seika and Co.,
Japan) was dissolved in 40 cm3 N,N-dimethylacetamide (DMAC) and then 4.112 g (0.008 mole) of 1,4-bis-(3,4-dicarbophenoxy)-2,5- di-tertiary-butylbenzene dianhydride was added and the mixture was heated to 50-600C for 10 minutes to dissolve the anhydride. Then 0.644 g (0.002 mole) of 3,3',4,4'-benzophenonetetracarboxylic dianhydride was added. The mixture was allowed to react for 24 hours and the resulting polyamic acid was imidized with a mixture of 10 cm3 of an equivolume mixture of acetic anhydride and pyridine. After six hours reaction the product was precipitated into methanol.After drying the polymer was redissolved in chloroform (70 cm3) and reprecipitated into methanol, filtered and dried. The yield was 7 g (almost theoretical). The whole of the synthesis and work-up were carried out in a laboratory illuminated with inactive sodium light.
The tertiary butyl dianhydride was synthesised as follows:4-fluorophthalic anhydride (7.3 g, 0.044 mol.) 2,5 di-tertiary-butyl hydroquinone (4.44 g, 0.02 mol.), spray-dried potassium fluoride (5.8 g, 0.1 mol.) and dry dimethyl acetamide (45 ml) were heated together at reflux with stirring and under a dry nitrogen atmosphere for five hours. The resultant mixture was cooled, poured into ice, filtered to dryness. The dried product was recrystallised from acetic anhydride, filtered, washed with ether and dried. The yield of product was 5.65 g (55%) at 96.9% purity by HPLC. Further recrystallisation from acetic anhydride gave a product which was 99.3% pure.
3,3'5,5' -tetramethyl-4, 4' -diaminodiphenylmethane TM diamine
1,4-bis-(3,4-dicarbophenoxy)-2,5-di-tertiary-butylbenzene dianhydride
= BHDA dianhydride
3,3',4,4'-benzophenonetetracarboxylic dianhydride
= BTDA dianhydride
The resultant cross linked membranes can be used for microfiltration and ultrafiltration applications as well as for gas separations.
Claims (3)
1. A copolyimide comprising 95-50% of structural repeating unit A and 5-50% of structural repeating unit B.
2. A method of synthesising a copolyimide comprising the steps of (a) dissolving TM diamine in a suitable solvent (b) adding to the diamine solution a mixture of BHDA and BTDA dianhydrides in a weight percent ratio from 20:1 to 1:1 and (c) allowing the reactants to polymerise.
3. A method of forming a gas separation membrane from a copolyimide according to claim 1 comprising the steps of dissolving the copolyimide in a solvent, spreading the resultant solution onto a substrate, allowing the solvent to evaporate to form a membrane on the substrate and subsequently removing the membrane.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB909013509A GB9013509D0 (en) | 1990-06-16 | 1990-06-16 | Polymer synthesis |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9111107D0 GB9111107D0 (en) | 1991-07-17 |
| GB2244997A true GB2244997A (en) | 1991-12-18 |
Family
ID=10677768
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB909013509A Pending GB9013509D0 (en) | 1990-06-16 | 1990-06-16 | Polymer synthesis |
| GB9111107A Withdrawn GB2244997A (en) | 1990-06-16 | 1991-05-23 | Copolyimides for use as gas separation membranes |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB909013509A Pending GB9013509D0 (en) | 1990-06-16 | 1990-06-16 | Polymer synthesis |
Country Status (1)
| Country | Link |
|---|---|
| GB (2) | GB9013509D0 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5248319A (en) * | 1992-09-02 | 1993-09-28 | E. I. Du Pont De Nemours And Company | Gas separation membranes made from blends of aromatic polyamide, polymide or polyamide-imide polymers |
| US5266100A (en) * | 1992-09-02 | 1993-11-30 | E. I. Du Pont De Nemours And Company | Alkyl substituted polyimide, polyamide and polyamide-imide gas separation membranes |
| US6706088B2 (en) * | 2000-06-02 | 2004-03-16 | Nissan Chemical Industries | Method for controlling membrane permeability by microwave and method for producing organic separation membrane |
| WO2013028719A1 (en) * | 2011-08-22 | 2013-02-28 | Sabic Innovative Plastics Ip B.V. | Polyetherimide compositions and methods for the manufacture and use thereof |
-
1990
- 1990-06-16 GB GB909013509A patent/GB9013509D0/en active Pending
-
1991
- 1991-05-23 GB GB9111107A patent/GB2244997A/en not_active Withdrawn
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5248319A (en) * | 1992-09-02 | 1993-09-28 | E. I. Du Pont De Nemours And Company | Gas separation membranes made from blends of aromatic polyamide, polymide or polyamide-imide polymers |
| US5266100A (en) * | 1992-09-02 | 1993-11-30 | E. I. Du Pont De Nemours And Company | Alkyl substituted polyimide, polyamide and polyamide-imide gas separation membranes |
| US6706088B2 (en) * | 2000-06-02 | 2004-03-16 | Nissan Chemical Industries | Method for controlling membrane permeability by microwave and method for producing organic separation membrane |
| WO2013028719A1 (en) * | 2011-08-22 | 2013-02-28 | Sabic Innovative Plastics Ip B.V. | Polyetherimide compositions and methods for the manufacture and use thereof |
| US9688816B2 (en) | 2011-08-22 | 2017-06-27 | Sabic Global Technologies B.V. | Polyetherimide compositions and methods for the manufacture and use thereof |
| KR101827466B1 (en) | 2011-08-22 | 2018-02-08 | 사빅 글로벌 테크놀러지스 비.브이. | Polyetherimide compositions and methods for the manufacture and use thereof |
| US10227452B2 (en) | 2011-08-22 | 2019-03-12 | Sabic Global Technologies B.V. | Polyetherimide compositions and methods for the manufacture and use thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9013509D0 (en) | 1990-08-08 |
| GB9111107D0 (en) | 1991-07-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |