CN102166484A - Hydrophilic polyvinylidene fluoride hollow fiber composite membrane and preparation method - Google Patents
Hydrophilic polyvinylidene fluoride hollow fiber composite membrane and preparation method Download PDFInfo
- Publication number
- CN102166484A CN102166484A CN2011101384344A CN201110138434A CN102166484A CN 102166484 A CN102166484 A CN 102166484A CN 2011101384344 A CN2011101384344 A CN 2011101384344A CN 201110138434 A CN201110138434 A CN 201110138434A CN 102166484 A CN102166484 A CN 102166484A
- Authority
- CN
- China
- Prior art keywords
- membrane
- pvdf
- fiber composite
- composite membrane
- hollow fiber
- 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
- 239000012528 membrane Substances 0.000 title claims abstract description 107
- 229920002981 polyvinylidene fluoride Polymers 0.000 title claims abstract description 80
- 239000002033 PVDF binder Substances 0.000 title claims abstract description 61
- 239000002131 composite material Substances 0.000 title claims abstract description 55
- 239000012510 hollow fiber Substances 0.000 title claims abstract description 54
- 238000002360 preparation method Methods 0.000 title claims abstract description 47
- 239000000835 fiber Substances 0.000 claims abstract description 30
- 238000005266 casting Methods 0.000 claims abstract description 26
- 229920001577 copolymer Polymers 0.000 claims abstract description 26
- 229920003171 Poly (ethylene oxide) Polymers 0.000 claims abstract description 18
- 230000010148 water-pollination Effects 0.000 claims abstract description 16
- 230000001112 coagulating effect Effects 0.000 claims abstract description 14
- -1 polyoxyethylene Polymers 0.000 claims abstract description 11
- 229920001451 polypropylene glycol Polymers 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 8
- 239000011248 coating agent Substances 0.000 claims abstract description 4
- 238000000576 coating method Methods 0.000 claims abstract description 4
- 239000000243 solution Substances 0.000 claims description 28
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 28
- 239000002904 solvent Substances 0.000 claims description 20
- 239000000203 mixture Substances 0.000 claims description 17
- 238000000465 moulding Methods 0.000 claims description 14
- 230000002209 hydrophobic effect Effects 0.000 claims description 9
- 239000000654 additive Substances 0.000 claims description 8
- 230000000996 additive effect Effects 0.000 claims description 8
- 239000003570 air Substances 0.000 claims description 7
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 6
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 6
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 6
- 238000009987 spinning Methods 0.000 claims description 6
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 5
- 239000002202 Polyethylene glycol Substances 0.000 claims description 5
- WFKAJVHLWXSISD-UHFFFAOYSA-N isobutyramide Chemical compound CC(C)C(N)=O WFKAJVHLWXSISD-UHFFFAOYSA-N 0.000 claims description 5
- 229920001223 polyethylene glycol Polymers 0.000 claims description 5
- 239000008367 deionised water Substances 0.000 claims description 4
- 229910021641 deionized water Inorganic materials 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 4
- 230000035699 permeability Effects 0.000 claims description 4
- 230000002688 persistence Effects 0.000 claims description 4
- 238000002791 soaking Methods 0.000 claims description 4
- 238000005406 washing Methods 0.000 claims description 4
- 206010013786 Dry skin Diseases 0.000 claims description 3
- 239000012080 ambient air Substances 0.000 claims description 3
- 229920001400 block copolymer Polymers 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 239000011259 mixed solution Substances 0.000 claims description 2
- 239000003960 organic solvent Substances 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 15
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 238000004140 cleaning Methods 0.000 abstract description 2
- 229920009405 Polyvinylidenefluoride (PVDF) Film Polymers 0.000 abstract 1
- 230000005923 long-lasting effect Effects 0.000 abstract 1
- 238000011282 treatment Methods 0.000 description 9
- 239000000463 material Substances 0.000 description 8
- 238000012986 modification Methods 0.000 description 8
- 230000004048 modification Effects 0.000 description 8
- 238000000926 separation method Methods 0.000 description 8
- 239000012071 phase Substances 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 5
- 230000004907 flux Effects 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000001471 micro-filtration Methods 0.000 description 3
- 239000004695 Polyether sulfone Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 230000004913 activation Effects 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 230000002045 lasting effect Effects 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 150000002894 organic compounds Chemical class 0.000 description 2
- 210000002381 plasma Anatomy 0.000 description 2
- 229920002432 poly(vinyl methyl ether) polymer Polymers 0.000 description 2
- 229920006393 polyether sulfone Polymers 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 238000000108 ultra-filtration Methods 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- 239000004696 Poly ether ether ketone Substances 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 229920004933 Terylene® Polymers 0.000 description 1
- QYKIQEUNHZKYBP-UHFFFAOYSA-N Vinyl ether Chemical compound C=COC=C QYKIQEUNHZKYBP-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000003926 acrylamides Chemical class 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000003373 anti-fouling effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 235000012489 doughnuts Nutrition 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 239000004811 fluoropolymer Substances 0.000 description 1
- 238000010559 graft polymerization reaction Methods 0.000 description 1
- 229920013821 hydroxy alkyl cellulose Polymers 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 210000001161 mammalian embryo Anatomy 0.000 description 1
- 239000011159 matrix material Substances 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
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920002530 polyetherether ketone Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Images
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a hydrophilic polyvinylidene fluoride hollow fiber composite membrane and a preparation method. The aperture of the membrane is 0.01 to 0.1 micron; the porosity of the membrane is 60 to 80 percent; a polyvinylidene fluoride (PVDF) film is coated on the outer surface of a hollow woven fiber pipe; the thickness of the coating is 0.1 to 0.4 millimeter; the outer diameter of the membrane is 1.5 to 2.5 millimeters; and the PVDF film comprises the following components in percentage by mass: 80 to 95 percent of polyvinylidene fluoride, and 5 to 20 percent of amphiphilic copolymer, namely polyoxyethylene/polyoxypropylene/polyoxyethylene (PEO-PPO-PEO). The preparation method sequentially comprises the following steps of: preparing film casting solution, coating the hollow woven fiber pipe, forming a coagulating bath, cleaning, drying and the like. The hollow fiber composite membrane prepared by the method is stable and long-lasting in structure; the hydrophily of the membrane can be obviously improved; and the production cost is reduced and mass production is easy to realize by the method.
Description
[technical field]
The invention belongs to separation membrane material structure and hydrophilic modification technical field, particularly a kind of suitable advanced treatment of wastewater reuse, handle to advanced water treatment, based on the preparation method of hydrophilic Kynoar hollow fiber composite membrane.
[background technology]
Membrane separation technique is as a kind of new separation technology, and its separation process has advantages such as low energy consumption, separating property are good, non-secondary pollution, is widely used in fields such as chemical industry, medicine, the energy, environmental project, water treatments at present.Selection to the separation membrane material of function admirable is the core of membrane separation technique, also is membrane separation technique Research on development emphasis.The separation membrane material of widely applying mostly is high molecular polymer at present, mainly contain polypropylene, polyethylene, polyvinyl chloride, polysulfones, polyether sulfone, polyamide, Merlon, acrylate copolymer, fluoropolymer etc., in numerous high molecular polymers, Kynoar (PVDF) is a kind of crystal polymer thing, C-F bond distance is short, the bond energy height, have good chemical stability and hear resistance, being to be used to one of preferred material for preparing diffusion barrier, is one of preferred material in preparation water treatment micro-filtration, milipore filter material.
At present in use mainly there is following problem in general Kynoar (PVDF) hollow-fibre membrane: the surface of (1) PVDF can be low, has strong-hydrophobicity, causes the hydrophily of film poor, contamination resistance is poor; (2) water flux of film and mechanical strength can not improve simultaneously; (3) mechanical strength of film is not high, causes film in use easily to break.Therefore, the strong-hydrophobicity of pvdf membrane and mechanical strength are the two big principal elements of restriction pvdf membrane in the water treatment field large-scale application.By pvdf membrane being carried out its water permeability of hydrophilically modified raising and antifouling property; Improve the mechanical strength of film greatly by the structure of composite membrane that applies the PVDF cortex at hollow braided fiber tube-surface.
The method of pvdf membrane hydrophilic modifying mainly is divided into membrane surface modification and membrane body (matrix) modification two classes.
The essence of membrane surface modification is to introduce polar group or hydrophily macromolecular chain on the film surface, mainly by methods such as chemical surface treatment, surface grafting, surface-coated.Though PVDF has good stable, can realize the performing hydrophilic modification on surface of Kynoar (PVDF) film under certain condition with strong acid, highly basic generation chemical reaction are introduced polarity on the film surface groups such as hydroxyl, carboxyl.Surface grafting mainly is to form the activated centre by technology such as light-initiated, radiation, plasmas on the membrane material surface, obtains long hydrophily chain on the film surface by graft polymerization reaction.Surface-coated mainly is by hydrogen bond, the mode of action such as crosslinked, introduces the hydrophilic cortex of one deck on the film surface.United States Patent (USP) (the patent No.: 2006157404) disclose a kind of method for preparing hydrophilic PVDF ultrafiltration/micro-filtration membrane, adopted, the stability of the further crosslinked raising hydrophilic layer by PVME at film surface-coated polymethyl vinyl ether (PVME) layer; (patent No.: 0249513) introduced the using plasma technology at unsaturated acrylic monomers such as pvdf membrane surface grafting acrylic acid, acrylamides, preparation has better hydrophilic PVDF microporous barrier to European patent.Chinese patent (the patent No.: 101293184) reported that the processing of employing radiation grafting at the inner carboxyl grafting in PVDF hollow-fibre membrane surface and hole, improves the hydrophily of film.
The membrane body method of modifying can be divided into chemical treatment modification and blend two classes.The chemical treatment modification is generally carried out in two steps: earlier PVDF is carried out " activation " and handle, make the active site that produces easy oxidation on its strand or generate free radical, again according to the feature of active site, select for use the PVDF after suitable reagent and " activation " processing to react, thereby directly on its strand, introduce hydroxyl, carboxyl isopolarity group or grafting hydrophilic monomer.Blending and modifying is according to the theory of polyblend compatibility and experimental study, select suitable hydrophilic component and PVDF to carry out being prepared into the hydrophilic PVDF blend film by the solution inversion of phases after the liquid phase blend, the good chemical stability and the hear resistance that had both kept PVDF possess the hydrophily of hydrophilic component again.United States Patent (USP) (the patent No.: 5151193) introduced the hydrophilic pvdf membrane of employing blend sulfonated polyether-ether-ketone (PEEKSO) preparation; European patent (the patent No.: 1464477,1682238) introduced the method that adopts blend cellulose acetate, polyvinylpyrrolidone, hydroxy alkyl cellulose etc., prepared hydrophilic PVDF ultrafiltration/micro-filtration membrane; Chinese patent (application number: 200810202882) introduced the method that adopts blend polyethersulfone, cellulose derivative etc., prepared hydrophilic PVDF hollow-fibre membrane.
The method of above-mentioned pvdf membrane hydrophilic modifying has solved problems such as the hydrophily, resistance tocrocking, water permeability of pvdf membrane in various degree, but the deficiency of unresolved PVDF hollow-fibre membrane bad mechanical strength.
Different with report in the past, the present invention combines the necessary factors such as stability of the film hydrophilically modified effect of PVDF doughnut and persistence, membrane structure, on the basis of fully experiment, disclose and a kind ofly contained the blending type pvdf membrane casting solution of amphipathic nature block polymer and be coated on the preparation method that hollow braided fiber tube-surface prepares the PVDF hollow fiber composite membrane based on solution inversion of phases principle.Prepared PVDF hollow fiber composite membrane has good hydrophilicity, resistance tocrocking and high water flux, and has high mechanical strength, is the membrane material that is specially adapted to the advanced treatment of wastewater reuse, handles to advanced water treatment.
[summary of the invention]
For solving above deficiency; the invention provides a kind of hydrophilicity kynoar hollow fiber composite membrane and preparation method; the hollow fiber composite membrane Stability Analysis of Structures prepared by this method is lasting, can significantly improve the hydrophily of film, and this method reduces production costs and accomplishes scale production easily.
The technical solution adopted in the present invention is: a kind of hydrophilicity kynoar hollow fiber composite membrane and preparation method is characterized in that, the fenestra aperture is that 0.01～0.1 micron, membrane porosity are 60%～80%, the pvdf membrane cortex is coated in hollow braided fiber tube outer surface, and coat thickness is that 0.1～0.4 millimeter, film external diameter are 1.5～2.5 millimeters; The component of pvdf membrane and mass percent are: Kynoar, 80%～95%; Amphipathic copolymer: polyoxyethylene/polyoxypropylene/polyoxyethylene (PEO-PPO-PEO) 5%～20%; Its preparation method is made up of steps such as preparation casting solution, the coating of hollow braided fiber pipe, coagulating bath moulding, cleaning-dryings successively.
Described a kind of hydrophilicity kynoar hollow fiber composite membrane and preparation method is characterized in that, its preparation method: (1) preparation casting solution: Kynoar, amphipathic copolymer, additive, solvent and non-solvent mix, abundant stirring and dissolving is 10～20 hours under 50～85 ℃, after filtration, obtain uniform casting solution after the vacuum defoamation, each component and the mass percent concentration thereof of casting solution are: Kynoar: number-average molecular weight is 4 * 10
4～1 * 10
6, mass percent concentration 10～20%; Amphipathic copolymer: polyoxyethylene/polyoxypropylene/polyoxyethylene, number-average molecular weight are 11500, mass percent concentration 0.5～3%; Additive: polyvinylpyrrolidone, number-average molecular weight are 3 * 10
4, mass percent concentration 0.5～6%; Polyethylene glycol, number-average molecular weight are 2 * 10
2～2 * 10
4, mass percent concentration 5～20%; Solvent: N, dinethylformamide, N, N-dimethylacetylamide or N-methyl pyrrolidone, mass percent concentration 65～85%; Non-solvent: water, mass percent concentration 0.2～2.5%;
(2) surface-coated: casting solution is applied the hollow braided fiber tube-surface with the given pace operation via special spinning head;
(3) hollow fiber composite membrane moulding: hollow braided fiber pipe that will be after casting solution applies immerses in 45～90 ℃ the coagulating tank, obtain Kynoar (PVDF) hollow fiber composite membrane of moulding through the inversion of phases coagulating bath, ambient air temperature is 15～40 ℃, envionmental humidity is 30～90 ℃, and the surrounding air segment distance is 5～20cm;
Described coagulating bath is the mixed solution of water and organic solvent, and the mass percent of its each component is: water: 40～100%; Solvent: N, dinethylformamide, N, identical with the casting solution solvent a kind of in N-dimethylacetylamide or the N-methyl pyrrolidone: 0～60%;
(4) cleaning-drying: Kynoar (PVDF) hollow fiber composite membrane of moulding with 30～50 ℃ of deionized water soaking and washing 24～48 hours, is dried in the air at room temperature and obtains described hydrophilicity kynoar (PVDF) hollow fiber composite membrane.
Described a kind of hydrophilicity kynoar hollow fiber composite membrane and preparation method is characterized in that, the amphipathic copolymer of blend is the block copolymer that contains hydrophilic segment and hydrophobic segment simultaneously, the existence of hydrophobic segment, make amphipathic copolymer and PVDF have good compatibility, guaranteed stability, the persistence of membrane structure; Hydrophilic segment is enriched in the surface of film in the preparation process of film, can significantly improve the hydrophily and the water permeability of film.
Described a kind of hydrophilicity kynoar hollow fiber composite membrane and preparation method is characterized in that, the hydrophilic component on blend film surface forms hydrated sheath by hydrogen bond, effectively hinder of the absorption of hydrophobic organic compound matter, improve film resistance tocrocking in use on the film surface.
Described a kind of hydrophilicity kynoar hollow fiber composite membrane and preparation method is characterized in that, by the supporting role of hollow establishment fibre pipe in pvdf membrane.
Beneficial effect of the present invention: 1, the amphipathic copolymer of Cai Yonging is the block copolymer that contains hydrophilic segment and hydrophobic segment simultaneously, according to the similar compatibility principle, the existence of hydrophobic segment makes amphipathic copolymer and PVDF have good compatibility, has guaranteed stability, the persistence of membrane structure.
2, the membrane preparation method of Cai Yonging, hydrophilic segment is enriched in the surface of film in the film forming procedure, is blended into the hydrophily that a spot of amphipathic copolymer can significantly improve film in PVDF.
3, the hydrophobic segment in the amphipathic copolymer makes the adhesion between PVDF and the amphipathic copolymer strong, and amphipathic copolymer is difficult for running off in the film use, guarantees that the hydrophily of film is lasting.
4, the hydrophilic component on blend film surface forms hydrated sheath by hydrogen bond, effectively hinders hydrophobic organic compound matter (as the organic colloidal matter in the activated sludge etc.) and in the absorption on film surface, improves film resistance tocrocking in use.
5, by the supporting role of hollow establishment fibre pipe in pvdf membrane, make film have high mechanical strength, guaranteed film endurance impact in use.
6, the preparation method of hydrophilic PVDF hollow fiber composite membrane provided by the invention, conditions such as the physical property of the composition of the length of the hydrophilic chain by controlling amphipathic copolymer and content, coagulating bath, system temperature, braided fiber pipe, spinning speed, membrane structure and performances such as the wall thickness of system's controlling diaphragm, aperture, porosity, hydrophily.
7. the outer surface aperture of Zhi Bei hollow fiber composite membrane is much smaller than the inner surface aperture, forms dissymmetrical structure, have the film of dissymmetrical structure contaminated after easier cleaning.
8, the preparation method of hydrophilic PVDF hollow fiber composite membrane provided by the invention adopts the method for the amphipathic copolymer of blend in casting solution; realized the integrated of the preparation of PVDF hollow fiber composite membrane and hydrophiling process; the efficient of preparation and modification improves; reduced production cost, accomplished scale production easily.
[description of drawings]
Fig. 1 is a structure chart of the present invention;
Fig. 2 prepares the equipment schematic diagram for the present invention;
Among the figure, 1-braided fiber pipe; The 2-guide roller; The embryo device is led in the 3-frequency conversion; The 4-stirred tank; 5-frequency conversion agitator; The 6-stirrer paddle; The 7-ball valve; The 8-filter; 9-feed liquid still; The 10-gear wheel metering pump; The 11-spinning head; 12-gel solidification tank; The 13-coil winding machine; 14-PVDF hymeniderm layer; 15-hollow braided fiber pipe.
[specific embodiment]
Below in conjunction with the drawings and specific embodiments the present invention is elaborated:
Fenestra disclosed in this invention aperture is that 0.01～0.1 micron, membrane porosity are 60～80%, the pvdf membrane skin thickness is that 0.1～0.4 millimeter, film external diameter are 1.5～2.5 millimeters, contain a kind of hydrophilicity kynoar hollow fiber composite membrane of amphipathic copolymer component and hollow braided fiber pipe, and the preparation method based on phase inversion technology who is made up of following step obtains:
(1) preparation casting solution: Kynoar, amphipathic copolymer, additive, solvent and non-solvent mix, 50～85 ℃ of abundant stirring and dissolving down, after filtration, obtain uniform casting solution after the standing and defoaming;
(2) surface-coated: casting solution is applied the hollow braided fiber tube-surface with the given pace operation via special spinning head;
(3) hollow fiber composite membrane moulding: hollow braided fiber pipe that will be after casting solution applies immerses in 45～90 ℃ the coagulating tank, obtains Kynoar (PVDF) hollow fiber composite membrane of moulding through the inversion of phases coagulating bath;
(4) cleaning-drying: Kynoar (PVDF) hollow fiber composite membrane of moulding with 30～50 ℃ of deionized water soaking and washing 24～48 hours, is dried in the air at room temperature and obtains described hydrophilicity kynoar (PVDF) hollow fiber composite membrane.
Kynoar of the present invention (PVDF), its number-average molecular weight are 4 * 10
4～1 * 10
6, mass percent concentration 10～20%.
Amphipathic copolymer of the present invention, polyoxyethylene/polyoxypropylene/polyoxyethylene (PEO-PPO-PEO), its number-average molecular weight is 11500, mass percent concentration 0.5～3%.
Additive polyvinylpyrrolidone of the present invention, number-average molecular weight are 3 * 10
4, mass percent concentration 0.5～6%; Polyethylene glycol, number-average molecular weight are 2 * 10
2～2 * 10
4, mass percent concentration 5～20%.
Solvent of the present invention: N, dinethylformamide, N, N-dimethylacetylamide or N-methyl pyrrolidone, mass percent concentration 65～85%.
Non-solvent of the present invention is a water, mass percent concentration 0.2～2.5%.
PVDF hollow fiber composite membrane profile and structural characterization: with the PVDF hollow fiber composite membrane for preparing, with SEM SIRION-100 (FEI, Finland) microstructure, the form of observation film surface and section; With mercury injection apparatus DEMO9500 (Micromecritics Instrument Corp, USA) porosity and the average pore size of mensuration film.
PVDF hollow fiber composite membrane hydrophily and hydrophilic stability characterize: freshly prepd PVDF hollow fiber composite membrane is following dry 10 hours at 65 ℃, drip method contact angle instrument OCA20 (Dataphysics with sitting, Germany) water is determined the hydrophily of film: contact angle (C at the contact angle on film surface
0) more little, the hydrophily of film is good more; The PVDF hollow fiber composite membrane is immersed 2 days (C of rinsing in 50 ℃ of deionized waters
2), 5 days (C
5), 15 days (C
15), film was taken out back 65 ℃ of following dryings 10 hours, measure the contact angle of water on the film surface more respectively, determine the stability of amphipathic copolymer in pvdf membrane according to the variation of contact angle: contact angle changes more little, and then the stability of amphipathic copolymer is good more in the pvdf membrane.
The mensuration of PVDF hollow fiber composite membrane water flux: choose the long PVDF hollow fiber composite membrane of 50 30cm and be packaged into a membrane component.Preacceleration inflation 30min under 0.15MPa measures the water flux of every 30min by film under 0.10MPa, each sample is surveyed and averaged for 5 times.
PVDF hollow fiber composite membrane of the following stated and preparation method's embodiment, the implementation step of all embodiment is all identical with aforementioned implementation step.Following examples are for a more detailed description to the present invention, but described embodiment is not construed as limiting the invention, and those skilled in the art all should think protection scope of the present invention from all distortion that content disclosed by the invention directly derives or associates.
Embodiment 1
The preparation of Kynoar (PVDF)/polyoxyethylene/polyoxypropylene/polyoxyethylene (PEO-PPO-PEO)/braided fiber pipe hollow fiber composite membrane
Its preparation process is as follows:
(1) configuration of casting solution:
With Kynoar, polyoxyethylene/polyoxypropylene/polyoxyethylene (PEO-PPO-PEO), additive (polyvinylpyrrolidone, polyethylene glycol), solvent (N, dinethylformamide) and non-solvent (water) blend, under 75 ℃, added thermal agitation 20 hours, filtration, vacuum defoamation 4 hours, obtain casting solution, each component of casting solution and mass percent concentration thereof are as follows:
Kynoar: number-average molecular weight is 2.1 * 10
5, mass percent concentration 10%;
Amphipathic copolymer: polyoxyethylene/polyoxypropylene/polyoxyethylene, number-average molecular weight are 11500, mass percent concentration 1%;
Additive: polyvinylpyrrolidone, number-average molecular weight are 3 * 10
4, mass percent concentration 0.5%; Polyethylene glycol, number-average molecular weight are 6 * 10
2, mass percent concentration 5%;
Solvent: N, dinethylformamide, mass percent concentration 81.5%;
Non-solvent: water, mass percent concentration 1%;
(2) surface-coated:
Adopt a kind of special terylene long fibre hollow braided tube, casting solution applies the hollow braided fiber tube-surface with the operation of 15m/min speed via special spinning head.
(3) hollow-fibre membrane moulding:
Hollow braided fiber pipe that will be after casting solution applies immerses in 50 ℃ the coagulating tank, obtain Kynoar (PVDF) hollow fiber composite membrane of moulding through the inversion of phases coagulating bath, ambient air temperature is 25 ℃, and envionmental humidity is 75 ℃, and the surrounding air segment distance is 12cm;
(4) cleaning-drying:
Kynoar (PVDF) hollow fiber composite membrane of moulding with 30 ℃ of deionized water soaking and washing 36 hours, is dried in 25 ℃ of air and obtained described hydrophilicity kynoar (PVDF) hollow fiber composite membrane in 48 hours.
The structure of the PVDF hollow fiber composite membrane of every implementation condition and preparation, performance are as shown in Table 1.
Table one
Table two
Table three
Table four
Table five
Table six
Claims (5)
1. hydrophilicity kynoar hollow fiber composite membrane and preparation method is characterized in that, the fenestra aperture is that 0.01～0.1 micron, membrane porosity are 60%～80%, the pvdf membrane cortex is coated in hollow braided fiber tube outer surface, and coat thickness is that 0.1～0.4 millimeter, film external diameter are 1.5～2.5 millimeters; The component of pvdf membrane and mass percent are: Kynoar, 80%～95%; Amphipathic copolymer: polyoxyethylene/polyoxypropylene/polyoxyethylene (PEO-PPO-PEO) 5%～20%; Its preparation method is made up of steps such as preparation casting solution, the coating of hollow braided fiber pipe, coagulating bath moulding, cleaning-dryings successively.
2. the described a kind of hydrophilicity kynoar hollow fiber composite membrane of claim 1, the amphipathic copolymer that it is characterized in that blend is the block copolymer that contains hydrophilic segment and hydrophobic segment simultaneously, the existence of hydrophobic segment, make amphipathic copolymer and PVDF have good compatibility, guaranteed stability, the persistence of membrane structure; Hydrophilic segment is enriched in the surface of film in the preparation process of film, can significantly improve the hydrophily and the water permeability of film.
3. the described a kind of hydrophilicity kynoar hollow fiber composite membrane of claim 1 is characterized in that the hydrophilic component on blend film surface forms hydrated sheath by hydrogen bond.
4. the described a kind of hydrophilicity kynoar hollow fiber composite membrane of claim 1 is characterized in that by the supporting role of hollow braided fiber pipe in pvdf membrane.
5. the preparation method of the described a kind of hydrophilicity kynoar hollow fiber composite membrane of claim 1 is characterized in that comprising the steps:
(1) preparation casting solution: Kynoar, amphipathic copolymer, additive, solvent and non-solvent mix, abundant stirring and dissolving is 10～20 hours under 50～85 ℃, after filtration, obtain uniform casting solution after the vacuum defoamation, each component and the mass percent concentration thereof of casting solution are:
Kynoar: number-average molecular weight is 4 * 10
4～1 * 10
6, mass percent concentration 10～20%;
Amphipathic copolymer: polyoxyethylene/polyoxypropylene/polyoxyethylene, number-average molecular weight are 11500, mass percent concentration 0.5～3%;
Additive: polyvinylpyrrolidone, number-average molecular weight are 3 * 10
4, mass percent concentration 0.5～6%; Polyethylene glycol, number-average molecular weight are 2 * 10
2～2 * 10
4, mass percent concentration 5～20%;
Solvent: N, dinethylformamide, N, N-dimethylacetylamide or N-methyl pyrrolidone, mass percent concentration 65～85%;
Non-solvent: water, mass percent concentration 0.2～2.5%;
(2) surface-coated: casting solution is applied the hollow braided fiber tube-surface with the given pace operation via special spinning head;
(3) hollow fiber composite membrane moulding: hollow braided fiber pipe that will be after casting solution applies immerses in 45～90 ℃ the coagulating tank, obtain Kynoar (PVDF) hollow fiber composite membrane of moulding through the inversion of phases coagulating bath, ambient air temperature is 15～40 ℃, envionmental humidity is 30～90 ℃, and the surrounding air segment distance is 5～20cm;
Described coagulating bath is the mixed solution of water and organic solvent, and the mass percent of its each component is: water: 40～100%; Solvent: N, dinethylformamide, N, identical with the casting solution solvent a kind of in N-dimethylacetylamide or the N-methyl pyrrolidone: 0～60%;
(4) cleaning-drying: Kynoar (PVDF) hollow fiber composite membrane of moulding with 30～50 ℃ of deionized water soaking and washing 24～48 hours, is dried in the air at room temperature and obtains described hydrophilicity kynoar (PVDF) hollow fiber composite membrane.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011101384344A CN102166484A (en) | 2011-05-15 | 2011-05-15 | Hydrophilic polyvinylidene fluoride hollow fiber composite membrane and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011101384344A CN102166484A (en) | 2011-05-15 | 2011-05-15 | Hydrophilic polyvinylidene fluoride hollow fiber composite membrane and preparation method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102166484A true CN102166484A (en) | 2011-08-31 |
Family
ID=44487916
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011101384344A Pending CN102166484A (en) | 2011-05-15 | 2011-05-15 | Hydrophilic polyvinylidene fluoride hollow fiber composite membrane and preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102166484A (en) |
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102512981A (en) * | 2012-01-10 | 2012-06-27 | 苏州汇龙膜技术发展有限公司 | Method for improving bonding performance of internal support hollow fiber composite membrane and internal support polyvinylidene fluoride hollow fiber membrane |
| CN102600734A (en) * | 2012-03-27 | 2012-07-25 | 南京工业大学 | Enhanced graphene oxide hollow fiber composite membrane and preparation method thereof |
| CN103007787A (en) * | 2012-12-19 | 2013-04-03 | 绍兴锐意环保科技有限公司 | Novel method for amphiphilic copolymer modified PVDF (Polyvinylidene Fluoride) hollow fiber ultra-filtration membranes |
| CN103157383A (en) * | 2011-12-13 | 2013-06-19 | 常州纺兴精密机械有限公司 | Internal-filtration multilayer hollow fibrous membrane |
| CN103157384A (en) * | 2011-12-13 | 2013-06-19 | 常州纺兴精密机械有限公司 | Multilayer hollow fibrous membrane |
| CN103191655A (en) * | 2013-04-01 | 2013-07-10 | 杭州求是膜技术有限公司 | Composite hollow fiber film and preparation method thereof |
| CN103394295A (en) * | 2013-08-14 | 2013-11-20 | 哈尔滨工业大学 | Hydrophilic PVDF (Polyvinylidene Fluoride) composite ultrafiltration membrane and preparation method thereof |
| CN103816818A (en) * | 2014-03-07 | 2014-05-28 | 浙江大学 | Super-hydrophilic and gradient hole structured hollow fiber membrane |
| CN103831018A (en) * | 2014-01-20 | 2014-06-04 | 天津工业大学 | Continuously-super-hydrophobic hollow fiber membrane and preparation method thereof |
| CN103861480A (en) * | 2014-03-21 | 2014-06-18 | 东华大学 | Preparation method of hydrophilic polyvinylidene fluoride flat sheet membrane and hollow fiber membrane |
| CN103877866A (en) * | 2014-03-27 | 2014-06-25 | 北京林业大学 | Preparation method of inorganic/organic hybrid arsenic-removing membrane |
| WO2016168644A1 (en) * | 2015-04-17 | 2016-10-20 | Georgia Tech Research Corporation | Hollow fiber membranes for solubilizing a gas into a liquid, devices for same, and processes of same |
| CN106360843A (en) * | 2016-09-22 | 2017-02-01 | 东华大学 | High-comfortableness nano fiber self-adhesion protective mask |
| CN107694355A (en) * | 2017-10-16 | 2018-02-16 | 三达膜科技（厦门）有限公司 | A kind of inner support Pvdf Microporous Hollow Fiber Membrane and preparation method thereof |
| CN107735165A (en) * | 2015-05-30 | 2018-02-23 | 迪博因特技术公司 | The water vapor transport membrane of support comprising polyethylene oxide copolymer |
| CN107913603A (en) * | 2017-10-09 | 2018-04-17 | 李亮 | Woven tube enhancement type hollow fiber film and its preparation facilities and production technology |
| CN108579437A (en) * | 2018-05-16 | 2018-09-28 | 天津工业大学 | A kind of big flux resistance to compression ultrafiltration membrane and preparation method thereof |
| CN108579470A (en) * | 2018-05-16 | 2018-09-28 | 天津工业大学 | It is a kind of high-throughput to stablize anti-pollution polyvinylidene fluoride ultrafiltration membrane and preparation method thereof |
| CN108786489A (en) * | 2012-06-29 | 2018-11-13 | 三菱化学株式会社 | Hollow form perforated membrane |
| CN110201559A (en) * | 2019-06-04 | 2019-09-06 | 泉州碧蓝膜科技有限责任公司 | A kind of big flux Enhanced type hollow fiber film and preparation method thereof |
| CN111888945A (en) * | 2020-07-31 | 2020-11-06 | 云南电网有限责任公司电力科学研究院 | A high-precision nanocomposite membrane |
| CN114230824A (en) * | 2020-09-09 | 2022-03-25 | 财团法人工业技术研究院 | Polyvinylidene fluoride film composition and polyvinylidene fluoride separator |
| CN116196780A (en) * | 2023-03-20 | 2023-06-02 | 苏州大学 | Modified porous separation membrane and preparation method and application thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101264428A (en) * | 2008-04-25 | 2008-09-17 | 浙江大学 | Method for modifying polyvinylidene fluoride ultrafiltration membrane with amphiphilic copolymer |
| CN101357303A (en) * | 2008-09-25 | 2009-02-04 | 杭州洁弗膜技术有限公司 | Preparation method of polyvinylidene fluoride hollow fiber composite microporous film with strong interface binding power |
| WO2009090174A1 (en) * | 2008-01-17 | 2009-07-23 | Whatman Inc | Composite membrane blends comprising ionic branch polymers and methods of use |
-
2011
- 2011-05-15 CN CN2011101384344A patent/CN102166484A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009090174A1 (en) * | 2008-01-17 | 2009-07-23 | Whatman Inc | Composite membrane blends comprising ionic branch polymers and methods of use |
| CN101264428A (en) * | 2008-04-25 | 2008-09-17 | 浙江大学 | Method for modifying polyvinylidene fluoride ultrafiltration membrane with amphiphilic copolymer |
| CN101357303A (en) * | 2008-09-25 | 2009-02-04 | 杭州洁弗膜技术有限公司 | Preparation method of polyvinylidene fluoride hollow fiber composite microporous film with strong interface binding power |
Non-Patent Citations (1)
| Title |
|---|
| YONG-HONG ZHAO等: "Modification of porous poly(vinylidene fluoride ) membrane using amphiphilic polymers with different structures in phase inversion process", 《JOURNAL OF MEMBRANE SCIENCE》 * |
Cited By (31)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103157383B (en) * | 2011-12-13 | 2016-08-24 | 常州纺兴精密机械有限公司 | Inner filtration multilayer hollow fiber film |
| CN103157383A (en) * | 2011-12-13 | 2013-06-19 | 常州纺兴精密机械有限公司 | Internal-filtration multilayer hollow fibrous membrane |
| CN103157384A (en) * | 2011-12-13 | 2013-06-19 | 常州纺兴精密机械有限公司 | Multilayer hollow fibrous membrane |
| CN103157384B (en) * | 2011-12-13 | 2016-08-24 | 常州纺兴精密机械有限公司 | Multilayer hollow fiber film |
| CN102512981A (en) * | 2012-01-10 | 2012-06-27 | 苏州汇龙膜技术发展有限公司 | Method for improving bonding performance of internal support hollow fiber composite membrane and internal support polyvinylidene fluoride hollow fiber membrane |
| CN102600734B (en) * | 2012-03-27 | 2014-12-10 | 南京工业大学 | Enhanced graphene oxide hollow fiber composite membrane and preparation method thereof |
| CN102600734A (en) * | 2012-03-27 | 2012-07-25 | 南京工业大学 | Enhanced graphene oxide hollow fiber composite membrane and preparation method thereof |
| CN108786489A (en) * | 2012-06-29 | 2018-11-13 | 三菱化学株式会社 | Hollow form perforated membrane |
| CN103007787A (en) * | 2012-12-19 | 2013-04-03 | 绍兴锐意环保科技有限公司 | Novel method for amphiphilic copolymer modified PVDF (Polyvinylidene Fluoride) hollow fiber ultra-filtration membranes |
| CN103191655A (en) * | 2013-04-01 | 2013-07-10 | 杭州求是膜技术有限公司 | Composite hollow fiber film and preparation method thereof |
| CN103394295A (en) * | 2013-08-14 | 2013-11-20 | 哈尔滨工业大学 | Hydrophilic PVDF (Polyvinylidene Fluoride) composite ultrafiltration membrane and preparation method thereof |
| CN103831018B (en) * | 2014-01-20 | 2017-01-18 | 天津工业大学 | Continuously-super-hydrophobic hollow fiber membrane and preparation method thereof |
| CN103831018A (en) * | 2014-01-20 | 2014-06-04 | 天津工业大学 | Continuously-super-hydrophobic hollow fiber membrane and preparation method thereof |
| CN103816818A (en) * | 2014-03-07 | 2014-05-28 | 浙江大学 | Super-hydrophilic and gradient hole structured hollow fiber membrane |
| CN103861480A (en) * | 2014-03-21 | 2014-06-18 | 东华大学 | Preparation method of hydrophilic polyvinylidene fluoride flat sheet membrane and hollow fiber membrane |
| CN103877866A (en) * | 2014-03-27 | 2014-06-25 | 北京林业大学 | Preparation method of inorganic/organic hybrid arsenic-removing membrane |
| WO2016168644A1 (en) * | 2015-04-17 | 2016-10-20 | Georgia Tech Research Corporation | Hollow fiber membranes for solubilizing a gas into a liquid, devices for same, and processes of same |
| CN107735165A (en) * | 2015-05-30 | 2018-02-23 | 迪博因特技术公司 | The water vapor transport membrane of support comprising polyethylene oxide copolymer |
| CN106360843B (en) * | 2016-09-22 | 2017-10-31 | 东华大学 | A kind of high-comfort nanofiber self-adhesion protective mask |
| CN106360843A (en) * | 2016-09-22 | 2017-02-01 | 东华大学 | High-comfortableness nano fiber self-adhesion protective mask |
| CN107913603A (en) * | 2017-10-09 | 2018-04-17 | 李亮 | Woven tube enhancement type hollow fiber film and its preparation facilities and production technology |
| CN107913603B (en) * | 2017-10-09 | 2023-05-09 | 李亮 | Braided tube reinforced hollow fiber membrane, and preparation device and production process thereof |
| CN107694355A (en) * | 2017-10-16 | 2018-02-16 | 三达膜科技（厦门）有限公司 | A kind of inner support Pvdf Microporous Hollow Fiber Membrane and preparation method thereof |
| CN108579437A (en) * | 2018-05-16 | 2018-09-28 | 天津工业大学 | A kind of big flux resistance to compression ultrafiltration membrane and preparation method thereof |
| CN108579470A (en) * | 2018-05-16 | 2018-09-28 | 天津工业大学 | It is a kind of high-throughput to stablize anti-pollution polyvinylidene fluoride ultrafiltration membrane and preparation method thereof |
| CN110201559A (en) * | 2019-06-04 | 2019-09-06 | 泉州碧蓝膜科技有限责任公司 | A kind of big flux Enhanced type hollow fiber film and preparation method thereof |
| CN110201559B (en) * | 2019-06-04 | 2021-11-09 | 泉州碧蓝膜科技有限责任公司 | Large-flux reinforced hollow fiber membrane and preparation method thereof |
| CN111888945A (en) * | 2020-07-31 | 2020-11-06 | 云南电网有限责任公司电力科学研究院 | A high-precision nanocomposite membrane |
| CN114230824A (en) * | 2020-09-09 | 2022-03-25 | 财团法人工业技术研究院 | Polyvinylidene fluoride film composition and polyvinylidene fluoride separator |
| CN114230824B (en) * | 2020-09-09 | 2024-02-06 | 财团法人工业技术研究院 | Polyvinylidene fluoride film composition and polyvinylidene fluoride isolating film |
| CN116196780A (en) * | 2023-03-20 | 2023-06-02 | 苏州大学 | Modified porous separation membrane and preparation method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102166484A (en) | Hydrophilic polyvinylidene fluoride hollow fiber composite membrane and preparation method | |
| CN100584437C (en) | Hydrophilic polyvinylidene fluoride hollow fiber microporous membrane and preparation method thereof | |
| CN100544809C (en) | A method for hydrophilic modification of polyvinylidene fluoride membrane | |
| CN101637704B (en) | A graft-modified polymer filter membrane for water treatment and its preparation method | |
| Zhang et al. | Novel single-step hydrophobic modification of polymeric hollow fiber membranes containing imide groups: Its potential for membrane contactor application | |
| CN106731897B (en) | High-pollution-resistance polyvinylidene fluoride hollow fiber ultrafiltration membrane, and preparation method and device thereof | |
| CN103191651A (en) | Preparation method of hydrophilic polyvinylidene fluoride blended hollow fiber microporous membrane | |
| CN102824859B (en) | Method for preparing hollow fiber nanofiltration membrane by using thermally induced phase separation/interface cross linking synchronization method | |
| CN103816818B (en) | A kind of superhydrophilic gradient hole hollow fiber membrane and its preparation method | |
| CN1817427A (en) | Polymer microporous modification by corona induced grafting technology | |
| CN104437124A (en) | Self-cleaning polyvinylidene fluoride microporous film and preparation method thereof | |
| CN103495348B (en) | A kind of PVC hollow fiber ultrafiltration membrane and preparation method thereof | |
| CN103127841A (en) | Polyvinylidene fluoride hydrophilic modified membrane and preparation method thereof | |
| CN103861476A (en) | Preparation method of polyvinylidene fluoride (PVDF) composite mesoporous membrane | |
| CN110327787A (en) | A kind of enhancement type hollow fiber film, preparation method and device | |
| CN109865501B (en) | Preparation method of composite membrane for adsorbing and removing organic dye in water | |
| CN107789986A (en) | Enhanced hollow fiber ultrafiltration membrane and preparation method thereof | |
| CN106632922B (en) | The method of the preparation method and its modified polyvinilidene fluoride microfiltration membranes of block polymer containing hydrophilic segment | |
| CN106268371A (en) | A kind of polyacrylonitrile hollow fiber ultrafilter membrane and preparation method thereof | |
| CN110917894B (en) | Preparation method of polyvinylidene fluoride hollow fiber porous membrane | |
| CN100337730C (en) | Preparation method of structurally symmetrical polyethersulfone hydrophilic microporous membrane | |
| CN112516817A (en) | Polyvinylidene fluoride loose nanofiltration membrane and preparation method and application thereof | |
| CN215539887U (en) | Preparation device of poly 4-methyl-1-pentene hollow fiber membrane for ECMO | |
| CN114377555A (en) | Hollow fiber humidifying membrane and preparation method and application thereof | |
| CN106178974B (en) | A kind of nano modification enhancement type hollow fiber film and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20110831 |