CN112774466B - High-flux high-strength polytetrafluoroethylene hollow fiber membrane and preparation method thereof - Google Patents
High-flux high-strength polytetrafluoroethylene hollow fiber membrane and preparation method thereof Download PDFInfo
- Publication number
- CN112774466B CN112774466B CN202011494903.1A CN202011494903A CN112774466B CN 112774466 B CN112774466 B CN 112774466B CN 202011494903 A CN202011494903 A CN 202011494903A CN 112774466 B CN112774466 B CN 112774466B
- Authority
- CN
- China
- Prior art keywords
- polytetrafluoroethylene
- polytetrafluoroethylene hollow
- hollow tube
- parts
- stretching
- 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.)
- Active
Links
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
- B01D71/30—Polyalkenyl halides
- B01D71/32—Polyalkenyl halides containing fluorine atoms
- B01D71/36—Polytetrafluoroethene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
-
- 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
- B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/02—Details relating to pores or porosity of the membranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/24—Mechanical properties, e.g. strength
Abstract
The invention discloses a high-flux high-strength polytetrafluoroethylene hollow fiber membrane and a preparation method thereof, wherein the preparation method comprises the following steps: uniformly mixing polytetrafluoroethylene dispersion resin, glass fiber, nano silicon dioxide and silicone oil, and standing for 1-2 hours at 50-70 ℃ to obtain a mixed material; pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube; stretching a polytetrafluoroethylene hollow tube 1.2-1.8 times at 200-250 ℃, then stretching the polytetrafluoroethylene hollow tube 1-2 times at 290-360 ℃, then stretching the polytetrafluoroethylene hollow tube 2-4 times at 370-390 ℃, and then sintering and molding at 350-400 ℃; placing the sintered polytetrafluoroethylene hollow tube in polytetrafluoroethylene emulsion for soaking and drying, and then sintering again to obtain the polytetrafluoroethylene hollow fiber membrane; the polytetrafluoroethylene hollow cellulose membrane prepared by the preparation method has higher porosity and membrane flux, and can improve the mechanical strength of the polytetrafluoroethylene cellulose membrane.
Description
Technical Field
The invention relates to the technical field of hollow fiber membranes, in particular to a high-flux high-strength polytetrafluoroethylene hollow fiber membrane and a preparation method thereof.
Background
The polytetrafluoroethylene hollow fiber membrane can be widely applied to membrane separation processes such as microfiltration, ultrafiltration and a membrane reactor; the polytetrafluoroethylene hollow fiber membrane has the advantages of acid and alkali resistance, oxidation resistance, microbial corrosion resistance and the like, and has remarkable advantages compared with hollow fiber membranes made of other materials in microfiltration and ultrafiltration.
At present, the existing polytetrafluoroethylene hollow fiber membrane is blocked in the process of filtering particles, so that the membrane flux is reduced, the filtering performance is lower, and the mechanical performance is poorer.
Disclosure of Invention
The invention aims to provide a high-flux high-strength polytetrafluoroethylene hollow fiber membrane and a preparation method thereof.
In order to achieve the above purpose of the present invention, the following technical solutions are adopted:
the invention provides a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which comprises the following steps:
(a) Uniformly mixing polytetrafluoroethylene dispersion resin, glass fiber, nano silicon dioxide and silicone oil, and standing for 1-2 hours at 50-70 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube;
(c) Stretching a polytetrafluoroethylene hollow tube by 1.2-1.8 times at 200-250 ℃, then stretching by 1-2 times at 290-360 ℃, then stretching by 2-4 times at 370-390 ℃, and then sintering and molding at 350-400 ℃;
(d) And placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion for soaking and drying, and then sintering again to obtain the polytetrafluoroethylene hollow fiber membrane.
The method of the invention can ensure that the prepared polytetrafluoroethylene hollow cellulose membrane has higher porosity and membrane flux through the limitation of all raw materials and all parameters, and can improve the mechanical strength of the polytetrafluoroethylene cellulose membrane at the same time.
Preferably, in the step (a), the mixed material comprises the following components in parts by weight:
70-80 parts of polytetrafluoroethylene dispersion resin, 3-6 parts of glass fiber, 4-8 parts of nano silicon dioxide and 15-30 parts of silicone oil.
Preferably, in the step (b), the temperature of extrusion molding is 120-160 ℃; the extrusion speed is 180-240 cm/min.
Preferably, in the step (c), the sintering time is 10 to 20s.
Preferably, in the step (d), the soaking time is 1-2 h, and the soaking temperature is 30-60 ℃.
Preferably, in the step (d), the drying temperature is 60-80 ℃, and the drying time is 0.5-1 h.
Preferably, in the step (d), the sintering temperature is 350-390 ℃, and the sintering time is 10-20 s.
The invention provides a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which is prepared by the preparation method.
Compared with the prior art, the invention has the beneficial effects that at least:
the method of the invention can ensure that the prepared polytetrafluoroethylene hollow cellulose membrane has higher porosity and membrane flux through the limitation of all raw materials and all parameters, and can improve the mechanical strength of the polytetrafluoroethylene cellulose membrane at the same time.
Detailed Description
The embodiments of the present invention will be described in detail with reference to the following examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.
Example 1
The embodiment is a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which comprises the following steps:
(a) Uniformly mixing 80 parts of polytetrafluoroethylene dispersion resin, 3 parts of glass fiber, 8 parts of nano silicon dioxide and 15 parts of silicone oil, and standing for 2 hours at 60 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube, wherein the extrusion molding temperature is 160 ℃, and the extrusion speed is 240cm/min;
(c) Stretching a polytetrafluoroethylene hollow tube 1.8 times at 250 ℃, then stretching the polytetrafluoroethylene hollow tube 1 time at 290 ℃, then stretching the polytetrafluoroethylene hollow tube 2 times at 370 ℃, and then sintering and molding the polytetrafluoroethylene hollow tube for 10s at 400 ℃;
(d) And (3) placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion, soaking for 1h at 60 ℃, then drying for 0.5h at 80 ℃, and then sintering for 10s at 390 ℃ to obtain the polytetrafluoroethylene hollow fiber membrane.
Example 2
The embodiment is a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which comprises the following steps:
(a) Uniformly mixing 70 parts of polytetrafluoroethylene dispersion resin, 6 parts of glass fiber, 4 parts of nano silicon dioxide and 30 parts of silicone oil, and standing for 2 hours at 60 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube, wherein the extrusion molding temperature is 150 ℃, and the extrusion speed is 240cm/min;
(c) Stretching a polytetrafluoroethylene hollow tube 1.2 times at 200 ℃, then stretching the polytetrafluoroethylene hollow tube 2 times at 360 ℃, then stretching the polytetrafluoroethylene hollow tube 4 times at 390 ℃, and then sintering and molding the polytetrafluoroethylene hollow tube at 400 ℃ for 20s;
(d) And (3) placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion, soaking for 1h at 60 ℃, then drying for 0.5h at 80 ℃, and then sintering for 20s at 390 ℃ to obtain the polytetrafluoroethylene hollow fiber membrane.
Example 3
The embodiment is a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which comprises the following steps:
(a) Uniformly mixing 75 parts of polytetrafluoroethylene dispersion resin, 5 parts of glass fiber, 6 parts of nano silicon dioxide and 20 parts of silicone oil, and standing for 2 hours at 60 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube, wherein the extrusion molding temperature is 140 ℃, and the extrusion speed is 200cm/min;
(c) Stretching a polytetrafluoroethylene hollow tube by 1.5 times at 220 ℃, then stretching the polytetrafluoroethylene hollow tube by 2 times at 330 ℃, then stretching the polytetrafluoroethylene hollow tube by 3 times at 380 ℃, and then sintering and molding the polytetrafluoroethylene hollow tube for 15s at 380 ℃;
(d) And (3) placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion, soaking for 1h at 60 ℃, then drying for 0.5h at 80 ℃, and then sintering for 15s at 380 ℃ to obtain the polytetrafluoroethylene hollow fiber membrane.
Example 4
The embodiment is a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which comprises the following steps:
(a) Uniformly mixing 70 parts of polytetrafluoroethylene dispersion resin, 5 parts of glass fiber, 6 parts of nano silicon dioxide and 30 parts of silicone oil, and standing for 2 hours at 60 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube, wherein the extrusion molding temperature is 120 ℃, and the extrusion speed is 180cm/min;
(c) Stretching a polytetrafluoroethylene hollow tube by 1.2 times at 200 ℃, then stretching by 1 time at 290 ℃, then stretching by 2 times at 370 ℃, and then sintering and molding for 10s at 350 ℃;
(d) And (3) placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion, soaking for 1h at 60 ℃, then drying for 1h at 60 ℃, and then sintering for 20s at 350 ℃ to obtain the polytetrafluoroethylene hollow fiber membrane.
Example 5
The embodiment is a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which comprises the following steps:
(a) Uniformly mixing 80 parts of polytetrafluoroethylene dispersion resin, 6 parts of glass fiber, 6 parts of nano silicon dioxide and 20 parts of silicone oil, and standing for 2 hours at 60 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube, wherein the extrusion molding temperature is 140 ℃, and the extrusion speed is 200cm/min;
(c) Stretching a polytetrafluoroethylene hollow tube 1.5 times at 220 ℃, then stretching the polytetrafluoroethylene hollow tube 2 times at 360 ℃, then stretching the polytetrafluoroethylene hollow tube 2 times at 370 ℃, and then sintering and molding the polytetrafluoroethylene hollow tube for 20s at 380 ℃;
(d) And (3) placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion, soaking for 2h at 30 ℃, then drying for 1h at 60 ℃, and then sintering for 20s at 380 ℃ to obtain the polytetrafluoroethylene hollow fiber membrane.
Comparative example 1
The comparative example is a method for preparing a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which is substantially the same as the preparation method of example 3 except that the step (c) is as follows:
the polytetrafluoroethylene hollow tube was further stretched 2 times at 330 ℃ and subsequently 4.5 times at 380 ℃ and then sintered at 380 ℃ for 15 seconds.
Comparative example 2
The comparative example is a preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane, which is substantially the same as the preparation method in example 3 except that the step (a) is as follows:
and uniformly mixing 75 parts of polytetrafluoroethylene dispersion resin, 8 parts of glass fiber, 3 parts of nano silicon dioxide and 20 parts of silicone oil, and standing for 2 hours at 60 ℃ to obtain a mixed material.
Examples of the experiments
Selecting the polytetrafluoroethylene hollow cellulose membranes prepared in the above example 3 and comparative examples 1-2 respectively;
detecting the porosity of different hollow cellulose membranes by adopting an aperture analyzer according to GB/T201003-2006, and detecting the tensile strength and the tensile strength of a single hollow cellulose membrane, wherein the detection results are shown in Table 1:
TABLE 1
| Group of | Porosity of the material | Tensile strength (MPa) |
| Example 3 | 93.4％ | 13.4 |
| Comparative example 1 | 72.1％ | 11.3 |
| Comparative example 2 | 91.2％ | 9.7 |
As can be seen from Table 1:
the polytetrafluoroethylene hollow cellulose membrane prepared in example 3 has more excellent porosity and tensile strength than the hollow cellulose membranes prepared in comparative examples 1 and 2, and therefore, the polytetrafluoroethylene hollow cellulose membrane prepared in the invention has more excellent membrane flux and mechanical strength by specifically limiting the use amount of each raw material component and the preparation process.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being covered by the appended claims and their equivalents.
Claims (7)
1. A preparation method of a high-flux high-strength polytetrafluoroethylene hollow fiber membrane is characterized by comprising the following steps:
(a) Uniformly mixing polytetrafluoroethylene dispersion resin, glass fiber, nano silicon dioxide and silicone oil, and standing for 1-2 hours at 50-70 ℃ to obtain a mixed material;
(b) Pressing the mixed material into a cylindrical blank, and then performing extrusion molding on the blank to obtain a polytetrafluoroethylene hollow tube;
(c) Stretching a polytetrafluoroethylene hollow tube by 1.2-1.8 times at 200-250 ℃, then stretching by 1-2 times at 290-360 ℃, then stretching by 2-4 times at 370-390 ℃, and then sintering and molding at 350-400 ℃;
(d) Placing the sintered polytetrafluoroethylene hollow tube into polytetrafluoroethylene emulsion for soaking and drying, and then sintering again to obtain the polytetrafluoroethylene hollow fiber membrane;
in the step (a), the mixed material comprises the following components in parts by weight:
70-80 parts of polytetrafluoroethylene dispersion resin, 3-6 parts of glass fiber, 4-8 parts of nano silicon dioxide and 15-30 parts of silicone oil.
2. The method according to claim 1, wherein the extrusion molding temperature in the step (b) is 120 to 160 ℃; the extrusion speed is 180-240 cm/min.
3. The method according to claim 1, wherein the sintering time in step (c) is 10 to 20 seconds.
4. The method according to claim 1, wherein the soaking time in the step (d) is 1 to 2 hours, and the soaking temperature is 30 to 60 ℃.
5. The method according to claim 1, wherein in the step (d), the drying temperature is 60 to 80 ℃ and the drying time is 0.5 to 1 hour.
6. The method according to claim 1, wherein the sintering temperature is 350 to 390 ℃ and the sintering time is 10 to 20 seconds in the step (d).
7. A high-flux high-strength polytetrafluoroethylene hollow fiber membrane produced by the production method according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011494903.1A CN112774466B (en) | 2020-12-17 | 2020-12-17 | High-flux high-strength polytetrafluoroethylene hollow fiber membrane and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011494903.1A CN112774466B (en) | 2020-12-17 | 2020-12-17 | High-flux high-strength polytetrafluoroethylene hollow fiber membrane and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112774466A CN112774466A (en) | 2021-05-11 |
| CN112774466B true CN112774466B (en) | 2022-11-01 |
Family
ID=75751078
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011494903.1A Active CN112774466B (en) | 2020-12-17 | 2020-12-17 | High-flux high-strength polytetrafluoroethylene hollow fiber membrane and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112774466B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007112942A (en) * | 2005-10-21 | 2007-05-10 | Nitto Denko Corp | Polytetrafluoroethylene (ptfe) porous film, method for producing the same and air filter filter medium |
| JP2010110686A (en) * | 2008-11-05 | 2010-05-20 | Sumitomo Electric Fine Polymer Inc | Tube for support of porous multi-layered hollow fiber membrane, and porous multi-layered hollow fiber membrane using the same |
| KR20130109734A (en) * | 2012-03-28 | 2013-10-08 | 웅진케미칼 주식회사 | Manufacturing method of multilayer ptfe hollow fiber membrane having porosity |
| CN105521716A (en) * | 2016-01-04 | 2016-04-27 | 国家海洋局天津海水淡化与综合利用研究所 | Two-stage stretch preparation method of polytetrafluoroethylene hollow fiber membrane |
| CN107596925A (en) * | 2017-08-31 | 2018-01-19 | 杭州安诺过滤器材有限公司 | Heterogeneous hollow-fibre membrane of the poly- amylene of 4 methyl 1 radial direction and preparation method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103055721B (en) * | 2013-01-30 | 2015-06-17 | 四川大学 | Preparation method for high-flux high-strength polytetrafluoroethylene hollow fibrous membrane |
| JP2020015005A (en) * | 2018-07-26 | 2020-01-30 | 住友電気工業株式会社 | Hollow fiber membrane, and manufacturing method of hollow fiber membrane |
| CN109705465B (en) * | 2018-12-29 | 2021-03-05 | 中国科学院宁波材料技术与工程研究所 | Hollow polyolefin foam material and preparation method thereof |
-
2020
- 2020-12-17 CN CN202011494903.1A patent/CN112774466B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007112942A (en) * | 2005-10-21 | 2007-05-10 | Nitto Denko Corp | Polytetrafluoroethylene (ptfe) porous film, method for producing the same and air filter filter medium |
| JP2010110686A (en) * | 2008-11-05 | 2010-05-20 | Sumitomo Electric Fine Polymer Inc | Tube for support of porous multi-layered hollow fiber membrane, and porous multi-layered hollow fiber membrane using the same |
| KR20130109734A (en) * | 2012-03-28 | 2013-10-08 | 웅진케미칼 주식회사 | Manufacturing method of multilayer ptfe hollow fiber membrane having porosity |
| CN105521716A (en) * | 2016-01-04 | 2016-04-27 | 国家海洋局天津海水淡化与综合利用研究所 | Two-stage stretch preparation method of polytetrafluoroethylene hollow fiber membrane |
| CN107596925A (en) * | 2017-08-31 | 2018-01-19 | 杭州安诺过滤器材有限公司 | Heterogeneous hollow-fibre membrane of the poly- amylene of 4 methyl 1 radial direction and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| Effect of Stretching Parameters on Structure and Properties of Polytetrafluoroethylene Hollow-Fiber Membranes;Jia 等;《CHEMICAL ENGINEERING & TECHNOLOGY》;20160531;第39卷(第5期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112774466A (en) | 2021-05-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106835321B (en) | Polar polymer modified ultra-high molecular weight polyethylene fiber and preparation method thereof | |
| CN103055721B (en) | Preparation method for high-flux high-strength polytetrafluoroethylene hollow fibrous membrane | |
| CN102151491B (en) | Modified polyvinyl chloride alloy ultra-filtration membrane and preparation method of hollow fiber ultra-filtration membrane | |
| CN107090609B (en) | Preparation method of polylactic acid fiber for outdoor articles | |
| CN112774466B (en) | High-flux high-strength polytetrafluoroethylene hollow fiber membrane and preparation method thereof | |
| CN110644102A (en) | Processing technology of wear-resistant yarn | |
| CN111944119A (en) | High-toughness material based on environment-friendly bio-based for 3D printing and preparation method thereof | |
| CN108159898A (en) | The method that thermally induced phase separation prepares polyacrylonitrile-radical microporous barrier | |
| CN102029114A (en) | Hydrophilic hollow fiber membrane and preparation method thereof | |
| AU2021104813A4 (en) | Method for preparing hydrophilic polytetrafluoroethylene hollow fiber microfiltration membrane | |
| CN102389720A (en) | Polytetrafluoroethylene membrane with supporting materials and preparation method thereof | |
| CN104923093A (en) | Hollow fiber ultrafiltration membrane of water purifier and preparation method for hollow fiber ultrafiltration membrane | |
| CN108479432A (en) | A kind of preparation method of hydrophily phenolphthalein polyether sulfone composite nano fiber ultrafiltration membrane | |
| CN113289499B (en) | Internal pressure type hollow fiber ultrafiltration membrane and preparation method and application thereof | |
| CN112876707A (en) | Polytetrafluoroethylene film and preparation method thereof | |
| CN105413487A (en) | Polypropylene hollow fiber microporous film and preparation method thereof | |
| CN104353367B (en) | A kind of polyvinylidene fluoride hollow fiber composite membrane preparation method | |
| CN109224886B (en) | Polytetrafluoroethylene tubular microporous membrane and preparation method thereof | |
| CN207929014U (en) | A kind of preparation system of enhanced hollow fiber microfiltration membrane | |
| CN111036087A (en) | Anti-pollution hollow fiber ultrafiltration membrane and preparation method thereof | |
| CN108166254B (en) | Preparation method of polyester rubber cop with high adhesive strength | |
| CN112316756A (en) | High-strength and high-retention TIPS hollow fiber membrane and preparation method thereof | |
| CN111016235B (en) | Porous PTFE (Polytetrafluoroethylene) stretched pipe and manufacturing process and application thereof | |
| KR101105204B1 (en) | Manufacturing method of high strength hollow fiber membrane and high strength hollow fiber membrane thereby | |
| CN103768961B (en) | A kind of preparation method of Pvc Ultrafiltration Membrane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |