CN112044290A - Polysulfone-based block copolymer separation membrane - Google Patents
Polysulfone-based block copolymer separation membrane Download PDFInfo
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- CN112044290A CN112044290A CN202011008724.2A CN202011008724A CN112044290A CN 112044290 A CN112044290 A CN 112044290A CN 202011008724 A CN202011008724 A CN 202011008724A CN 112044290 A CN112044290 A CN 112044290A
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- 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
- B01D71/66—Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
- B01D71/68—Polysulfones; Polyethersulfones
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/06—Flat membranes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/08—Hollow fibre membranes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/10—Supported membranes; Membrane supports
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/12—Composite membranes; Ultra-thin membranes
Abstract
The present invention relates to a polysulfone-based block copolymer separation membrane having a multilayer structure of a support layer and a dense functional layer formed thereon. The main component of the compact functional layer is polysulfone block copolymer, and the compact functional layer is prepared by a one-step phase inversion method, a spraying method, a spin coating method or the like. In addition, the effective aperture of the compact functional layer of the separation membrane can be between 1 and 1000 nanometers by regulating and controlling a high-molecular membrane casting solution system. The polysulfone-based block copolymer separation membrane is widely applied to separation, concentration and purification processes in the fields of electronics, biology, medical treatment, chemical industry, petroleum, food, water treatment, seawater desalination, gas separation and the like.
Description
Technical Field
The present invention relates to a polysulfone-based block copolymer separation membrane. Can be applied to the separation, concentration and purification processes in the fields of electronics, biology, medical treatment, chemical industry, petroleum, food, water treatment, seawater desalination, gas separation and the like.
Background
In recent years, polysulfone family polymeric materials have been widely used for preparing separation membranes by virtue of their excellent properties such as chemical inertness, thermodynamic stability and mechanical strength, and are further used for separation or purification of gases and liquids. However, the pore size of the traditional polysulfone group polymeric separation membrane is generally in the range of microfiltration and ultrafiltration (the pore size is more than 20 nm), and is not easy to be regulated and controlled in the range of small pore size, and the traditional polysulfone group polymeric separation membrane also has the defects of low porosity, poor permeability selectivity, poor pollution resistance and the like, which seriously restrict the practical application of the polysulfone group polymeric separation membrane.
In order to improve the anti-pollution performance of polysulfone family polymeric separation membranes, researchers use amphiphilic block copolymers as additives to improve the hydrophilicity of the membrane surface, and patent CN 105032220 discloses that an anti-pollution polysulfone ultrafiltration membrane is prepared by a method of phase inversion after blending polysulfone and polysulfone block copolymers. The hydrophobic block in the amphiphilic polysulfone block copolymer can be firmly fixed on a membrane matrix, the hydrophilic block can be enriched on the surface of the membrane through regulation and control so as to improve the anti-pollution performance of the membrane, and meanwhile, the hydrophilic block and the hydrophobic block are fixed in the membrane through chemical bond chains, so that the elution and seepage of an additive are avoided. In addition, by blending the block copolymer material, the porosity, the pore diameter and the permselectivity of the membrane can be improved and effectively regulated. However, the blending addition amount of the block copolymer is generally low, the pore diameter and porosity of the membrane cannot be changed essentially, and the improvement on the structure and the permselectivity of the separation membrane is limited.
Disclosure of Invention
In order to further widen the pore diameter regulation range of polysulfone group separation membranes, increase the porosity of the membranes, and increase the permselectivity of the membranes, the present invention aims to develop a polysulfone-based block copolymer separation membrane having a multilayer structure of a support layer and a dense functional layer formed thereon. The main component of the compact functional layer is polysulfone block copolymer, and the compact functional layer is prepared by a one-step phase inversion method, a spraying method, a spin coating method or the like. In addition, the effective aperture of the compact functional layer of the separation membrane can be between 1 and 1000 nanometers by regulating and controlling a high-molecular membrane casting solution system. The polysulfone-based block copolymer separation membrane is widely applied to separation, concentration and purification processes in the fields of electronics, biology, medical treatment, chemical industry, petroleum, food, water treatment, seawater desalination, gas separation and the like.
The technical scheme of the invention is as follows:
a polysulfone-based block copolymer separation membrane characterized in that,
(a) the multilayer structure comprises a support layer and a compact functional layer formed on the support layer, and the interface of the compact functional layer and the support layer is a continuous structure.
(b) The compact functional layer and the support layer are both porous structures, wherein the effective pore diameter of the compact functional layer is between 1 and 1000 nanometers.
(c) The main component of the compact functional layer is polysulfone family block copolymer. The polysulfone family block copolymer is formed by chemically bonding a hydrophilic block A and a polysulfone family high polymer block B, wherein the hydrophilic block A is one or more of polyethylene glycol, hyperbranched polyglycerol ether, polypropylene glycol, polyethylene glycol monomethyl ether, polypropylene glycol monomethyl ether, cyclodextrin, polyethylene glycol methacrylate, polymethacrylate, polyoxypropylene, polyvinyl alcohol, polypropylene glycol, dextran, chitosan, polyacrylic acid and other high polymer materials, and the polysulfone family high polymer block B is one or more of polysulfone, polyether sulfone, polyphenylsulfone and sulfonated polysulfone.
(d) The support layer can be, but is not limited to, a polymer porous material, a ceramic porous material, and a metal porous material.
(e) The separation membrane may be in the form of a flat plate or a hollow fiber.
(f) The separation membrane can be used for filtering gas or liquid.
The polysulfone-based block copolymer separation membrane is characterized in that: the compact functional layer is prepared from polysulfone-based block copolymer membrane casting solution by a phase inversion method, a spraying method, a spin coating method or the like.
(a) The casting solution consists of 1-40 wt% of polysulfone family block copolymer, 0-50 wt% of pore-forming agent, 0-99 wt% of volatile solvent and 0-95 wt% of non-volatile solvent;
(b) the porogens in (a) are selected from but not limited to polymeric porogens and small molecule porogens: the polymer pore-forming agent comprises one or more of polyethylene glycol, polypropylene glycol, polyvinylpyrrolidone, cyclodextrin, hyperbranched polyglycerol ether, polyoxypropylene, polyoxyethylene polyoxypropylene ether block copolymer (poloxamer), polyvinyl alcohol, polyoxypropylene alcohol, dextran, polymethacrylic acid, polymethacrylate, chitosan and the like, and the small molecule pore-forming agent comprises one or more of but not limited to diethylene glycol, ethanol, ethylene glycol, isopropanol, glycerol, tween, span, sodium dodecyl sulfate, camphorsulfonic acid, tannic acid, dopamine, lithium chloride, sodium chloride, potassium chloride, zinc chloride, calcium carbonate, lithium nitrate and lithium perchlorate;
(c) the volatile solvent in (a) is selected from one or more of acetone, methyl ethyl ketone, tetrahydrofuran, dioxane, methyl acetate and ethyl acetate.
(d) The solvent which is difficult to volatilize in the step (a) is selected from one or more of N, N-dimethylacetamide, sulfolane, N-methylpyrrolidone, N-dimethylformamide, dimethyl sulfoxide and tetramethyl sulfoxide.
(e) The phase inversion method, the spraying method or the spin coating method are used for preparing the polysulfone-based block copolymer separation membrane, and the polysulfone-based block copolymer separation membrane is prepared by coating the membrane casting solution in the step (a) on a porous substrate through scraper coating, spraying, rotary coating and the like of a membrane casting machine, removing a solvent, curing to form a membrane, soaking in clear water and glycerol, and finally drying.
The polysulfone-based block copolymer separation membrane is widely applied to separation, concentration and purification processes in the fields of biology, medical treatment, chemical industry, food, water treatment, seawater desalination, gas separation and the like.
The invention has the beneficial effects that:
(1) the invention provides a polysulfone-based block copolymer separation membrane. The separation membrane has a multi-layer structure of a support layer and a dense functional layer formed thereon. The main component of the compact functional layer is polysulfone block copolymer, and the compact functional layer is prepared by a phase inversion method, a spraying method, a spin coating method or the like.
(2) The effective aperture of the compact separation membrane can be between 1 and 1000 nanometers only by regulating and controlling a high-molecular membrane casting solution system, and the method can be used for customizing a precise separation membrane according to the sizes of different separated objects.
(3) The preparation method of the membrane has clear thought and obvious effect, and belongs to the first case at home and abroad.
Detailed Description
The present invention will be described in further detail with reference to examples, but it should not be construed that the scope of the present invention is limited to the examples. Various substitutions and alterations can be made by those skilled in the art and by conventional means without departing from the spirit of the method of the invention described above. The method is a conventional method unless otherwise specified. The materials are commercially available from the open literature unless otherwise specified.
Example 1
8 wt% of PSf-b-PEG block copolymer (M)w: 33kDa, PDI: 2.05, PEG chain length: 5kDa, PEG content: 35.5 wt%) and 10 wt% of polyvinylpyrrolidone (K-30) are dissolved in N, N-dimethylacetamide, and the mixture is stirred, stood and defoamed at room temperature to obtain clear, uniform and stable casting solution. And uniformly pouring the casting solution onto a clean glass plate, scraping the casting solution into a thin film by using a self-made film scraping rod casting solution with a certain height, and putting the scraped casting solution into a 50 wt% deionized water and 50 wt% N, N-dimethylacetamide coagulating bath by using an immersion precipitation phase inversion method. After the membrane automatically falls off, the scraped PSf-b-PEG segmented copolymer membrane is placed in ionized water to be soaked for 12 hours, and the organic solvent remained in the membrane hole is completely removed, so that the PSf-b-PEG segmented copolymer membrane is obtained.
The average effective pore diameter of the tested membrane is 210nm, and the pure water flux can reach 8000L m–2h–1bar–1。
Example 2
15 wt% of PSf-b-PEG block copolymer (M)w: 54kDa, PDI: 1.57, PEG chain length: 5kDa, PEG content: 21 wt%) in N-methyl-2-pyrrolidone, stirring at room temperature, standing, and defoaming to obtain clear, uniform, and stable casting solution. Pouring the casting solution on a clean glass plate uniformly and using the self-made casting solutionAnd scraping the membrane casting solution with a membrane scraping rod with a certain height into a thin membrane, and putting the scraped membrane casting solution into a deionized water coagulating bath by an immersion precipitation phase inversion method. After the membrane automatically falls off, the scraped membrane is placed in the ionized water again to be soaked for 12 hours, and the organic solvent remained in the membrane hole is completely removed, so that the PSf-b-PEG segmented copolymer membrane is obtained.
The average effective pore diameter of the membrane calculated by using a PEG (polyethylene glycol) retention curve is 10.4nm, and the flux test of the membrane shows that the pure water flux can reach 980L m–2h–1bar–1The retention rate of bovine serum albumin reaches 98.3 percent.
Example 3
PSf-b-PEG block copolymer (M)w: 52kDa, PDI: 1.55, PEG chain length: 5kDa, PEG content: 11 wt%) of the mixed solution is dissolved in a mixed solvent of sulfolane and tetrahydrofuran (the mass ratio of sulfolane to tetrahydrofuran is 1/4.0), and the mixed solution is stirred, stood and defoamed at room temperature to obtain a clear, uniform and stable casting solution. And pouring the casting solution on a clean glass plate uniformly, scraping the casting solution into a thin film by using a self-made film scraping rod casting solution with a certain height, naturally volatilizing for 120s, and putting the scraped casting solution into a deionized water coagulating bath by an immersion precipitation phase conversion method. After the membrane automatically falls off, the scraped PSf-b-PEG segmented copolymer membrane is placed in ionized water to be soaked for 12 hours, and the organic solvent remained in the membrane hole is completely removed, so that the PSf-b-PEG segmented copolymer membrane is obtained.
The average effective pore diameter of the membrane calculated by using a PEG (polyethylene glycol) retention curve is 2.2nm, and the flux test of the membrane shows that the pure water flux can reach 7.0L m–2h–1bar–1The rejection rate of Congo red dye reaches 99.9%, and the rejection rate of divalent salt is only 0.1%.
Claims (3)
1. A polysulfone-based block copolymer separation membrane characterized in that,
(a) the multilayer structure is provided with a supporting layer and a compact functional layer formed on the supporting layer, and the interface of the compact functional layer and the supporting layer is a continuous structure;
(b) the compact functional layer and the supporting layer are both in porous structures, wherein the effective pore diameter of the compact functional layer is between 1 and 1000 nanometers;
(c) the main component of the compact functional layer is polysulfone family block copolymer. The polysulfone family block copolymer is a block copolymer formed by chemically bonding a hydrophilic block A and a polysulfone family high polymer block B, wherein the hydrophilic block A is one or more of polyethylene glycol, hyperbranched polyglycerol ether, polypropylene glycol, polyethylene glycol monomethyl ether, polypropylene glycol monomethyl ether, cyclodextrin, polyethylene glycol methacrylate, polymethacrylate, polyoxypropylene, polyvinyl alcohol, polypropylene glycol, dextran, chitosan, polyacrylic acid and other high polymer materials, and the polysulfone family high polymer block B is one or more of polysulfone, polyether sulfone, polyphenylsulfone and sulfonated polysulfone;
(d) the support layer can be, but is not limited to, a polymer porous material, a ceramic porous material, a metal porous material;
(e) the separation membrane can be in the form of a flat plate or a hollow fiber;
(f) the separation membrane can be used for filtering gas or liquid.
2. The polysulfone-based block-copolymer separation membrane of claim 1, wherein: the compact functional layer is prepared from polysulfone-based block copolymer membrane casting solution by a phase inversion method, a spraying method, a spin coating method or the like.
(a) The casting solution consists of 1-40 wt% of polysulfone family block copolymer, 0-50 wt% of pore-forming agent, 0-99 wt% of volatile solvent and 0-95 wt% of non-volatile solvent;
(b) the porogens in (a) are selected from but not limited to polymeric porogens and small molecule porogens: the polymer pore-forming agent comprises one or more of polyethylene glycol, polypropylene glycol, polyvinylpyrrolidone, cyclodextrin, hyperbranched polyglycerol ether, polyoxypropylene, polyoxyethylene polyoxypropylene ether block copolymer (poloxamer), polyvinyl alcohol, polyoxypropylene alcohol, dextran, polymethacrylic acid, polymethacrylate, chitosan and the like, and the small molecule pore-forming agent comprises one or more of but not limited to diethylene glycol, ethanol, ethylene glycol, isopropanol, glycerol, tween, span, sodium dodecyl sulfate, camphorsulfonic acid, tannic acid, dopamine, lithium chloride, sodium chloride, potassium chloride, zinc chloride, calcium carbonate, lithium nitrate and lithium perchlorate;
(c) the volatile solvent in (a) is selected from one or more of acetone, methyl ethyl ketone, tetrahydrofuran, dioxane, methyl acetate and ethyl acetate;
(d) the solvent which is difficult to volatilize in the step (a) is selected from one or more of N, N-dimethylacetamide, sulfolane, N-methylpyrrolidone, N-dimethylformamide, dimethyl sulfoxide and tetramethyl sulfoxide.
(e) The phase inversion method, the spraying method or the spin coating method are used for preparing the polysulfone-based block copolymer separation membrane, and the polysulfone-based block copolymer separation membrane is prepared by coating the membrane casting solution in the step (a) on a porous substrate through scraper coating, spraying, rotary coating and the like of a membrane casting machine, removing a solvent, curing to form a membrane, soaking in clear water and glycerol, and finally drying.
3. The polysulfone-based block copolymer separation membrane according to claim 1, which is widely used in separation, concentration and purification processes in the fields of electronics, biology, medical treatment, chemical industry, petroleum, food, water treatment, seawater desalination, gas separation, etc.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114213632A (en) * | 2021-12-14 | 2022-03-22 | 济南大学 | Preparation method and application of amphiphilic fluorine-containing copolymer membrane with protein adsorption resistance |
| CN115212736A (en) * | 2022-07-15 | 2022-10-21 | 中国科学院烟台海岸带研究所 | Separation membrane for seawater industrial aquaculture water treatment |
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| US20110240550A1 (en) * | 2010-03-31 | 2011-10-06 | General Electric Company | Block copolymer membranes and associated methods for making the same |
| CN105435660A (en) * | 2015-12-24 | 2016-03-30 | 中国科学院烟台海岸带研究所 | Anti-pollution composite multi-layer polymer separation membrane and preparation method thereof |
| CN106943899A (en) * | 2017-03-07 | 2017-07-14 | 南京工业大学 | A kind of hydrophilic polysulfone film and preparation method thereof |
| CN107570020A (en) * | 2017-10-24 | 2018-01-12 | 四川中科兴业高新材料有限公司 | A kind of polyaryl ether sulphone compound separation membrane and preparation method thereof |
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2020
- 2020-09-23 CN CN202011008724.2A patent/CN112044290A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110240550A1 (en) * | 2010-03-31 | 2011-10-06 | General Electric Company | Block copolymer membranes and associated methods for making the same |
| CN105435660A (en) * | 2015-12-24 | 2016-03-30 | 中国科学院烟台海岸带研究所 | Anti-pollution composite multi-layer polymer separation membrane and preparation method thereof |
| CN106943899A (en) * | 2017-03-07 | 2017-07-14 | 南京工业大学 | A kind of hydrophilic polysulfone film and preparation method thereof |
| CN107570020A (en) * | 2017-10-24 | 2018-01-12 | 四川中科兴业高新材料有限公司 | A kind of polyaryl ether sulphone compound separation membrane and preparation method thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114213632A (en) * | 2021-12-14 | 2022-03-22 | 济南大学 | Preparation method and application of amphiphilic fluorine-containing copolymer membrane with protein adsorption resistance |
| CN114213632B (en) * | 2021-12-14 | 2023-08-22 | 济南大学 | Preparation method and application of amphiphilic fluorine-containing copolymer membrane with protein adsorption resistance |
| CN115212736A (en) * | 2022-07-15 | 2022-10-21 | 中国科学院烟台海岸带研究所 | Separation membrane for seawater industrial aquaculture water treatment |
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Application publication date: 20201208 |