CN102343220A - Polyvinyl chloride membrane with supporting materials and preparation method thereof - Google Patents
Polyvinyl chloride membrane with supporting materials and preparation method thereof Download PDFInfo
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- CN102343220A CN102343220A CN2011102921568A CN201110292156A CN102343220A CN 102343220 A CN102343220 A CN 102343220A CN 2011102921568 A CN2011102921568 A CN 2011102921568A CN 201110292156 A CN201110292156 A CN 201110292156A CN 102343220 A CN102343220 A CN 102343220A
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Abstract
The invention discloses a polyvinyl chloride hollow fibrous membrane with supporting materials and a preparation method thereof. The preparation method of the polytetrafluoroethylene hollow fibrous composite membrane with the supporting materials comprises the following steps: taking polymethyl methacrylate as a hydrophilic agent, polyethylene glycol or polyvinylpyrrolidone as a pore-forming agent and N,N-dimethylacetamide or N,N-dimethylformamide as a solvent to prepare the polyvinyl chloride hollow fibrous membrane by a dry-wet method and blending the polyvinyl chloride hollow fibrous membrane with monofilament fibers, wherein the monofilament fibrous materials are polyester, spandex, nylon 6, nylon 66 or polyurethane and have diameter of 0.01-2mm. According to the invention, the defect that the hollow fibrous membranes without supports have insufficient physical tensile strength and are easy to suffer from filament break is overcome; the physical tensile strength of the membrane disclosed by the invention is improved by more than several times compared with that of the hollow fibrous membranes without supports; support and membrane stripping can be avoided; the water flux and manufacturing cost of the membrane disclosed by the invention are equivalent to those of the hollow fibers without supports; and the membrane can replace the existing hollow fiber products and has great economic and social benefits.
Description
Technical field
The present invention relates to composite, relate in particular to a kind of PVC hollow fiber membrane with backing material and preparation method thereof.
Background technology
Serious day by day water pollutes has nibbled the water resource that can supply consume in a large number, and what the shortage of water resource and water polluted increases the weight of, and is directly connected to the people's healthy and safe and social, economic sustainable development.Sewage disposal and regeneration are manual simulation and the reinforcements to water Natural Circulation process; 80% of urban water supply is converted into sewage; After collection and treatment, wherein 70% can recycle once more, this means through reusing sewage; Can have now under the constant situation of output, make the water volume that can be utilized in cities and towns increase more than 50%.
Traditional wastewater Regeneration Treatment technology exists shortcomings such as effluent characteristics is not high, occupation of land is big, poor stability.Membrane separation technique has advantages such as energy consumption is low, process is simple, separative efficiency is high, non-environmental-pollution; It is the important new and high technology that solves the contemporary energy, resource and environmental problem; Be that other any chemical separation technology is irreplaceable; It uses fields such as involved chemical industry, food, medicine, biochemistry, environmental protection, to energy savings, raise the efficiency, environment purification etc. made significant contribution, is called one of ten the most rising big new and high technologies of 21st century abroad.
The classification of liquid separating film according to the size of material to be separated matter, can be divided into micro-filtration, ultrafiltration, nanofiltration, counter-infiltration successively; According to the version of film, can be divided into doughnut, hollow tubular type, flat board, four kinds of structures of rolling; According to the material of film, can be divided into organic film, ceramic membrane, metal film.Wherein the Hollow Fiber Ultrafiltration of organic material, micro-filtration account for 35% of global liquid separating film market, are topmost liquid separating films.
Membrane material commonly used at present has cellulose acetate (CA), polysulfones (PS), polyether sulfone (PES), polyacrylonitrile (PAN), Kynoar (PVDF) etc., but the cost performance of these materials is lower, has restricted the application of film to a certain extent.Therefore seek a kind of cheaply, good filtration effect, the membrane material that materialization stability is high are extremely important.
Polyvinyl chloride (PVC) is a kind of synthetic resin material that uses a chlorine atom to replace a hydrogen atom in the polyethylene, has that resistance to acids and bases is strong, organic solvent-resistant, and the dry-wet spinning system of being applicable to film, wide material sources, and cost is low.Yet the toughness of PVC milipore filter is relatively poor, fragility is big, film can be spontaneous the contraction fracture, therefore, preparation intensity is big, the PVC hollow fiber membrane of good toughness, high flux, high rejection has important theory and realistic meaning.
Summary of the invention
The objective of the invention is to overcome the deficiency of prior art, a kind of PVC hollow fiber membrane with backing material and preparation method thereof is provided.
The polychloroethylene film of band backing material is: with the filter membrane of pvc material and 3 parallel blending formation of above monfil; Monfil is evenly distributed on the rete center after the film forming; Monfil is spandex, nylon 6 or polyurethane, and the diameter of monfil is the 0.01-2 millimeter.
The preparation method's of the polychloroethylene film of band backing material step is following:
1) concentration is the polyvinyl chloride of 13-19 wt/v %; Concentration is that 1-3 wt/v % hydrophilizing agent polymethyl methacrylate, concentration are the pore former of 4-15 wt/v %; Concentration is that the solvent of 55-80 wt/v % adds in the molten material still successively; The hurdle is pressed in the shaft sealing of open dissolving the material still, stirs under 40-90 ℃, obtains casting solution;
2) casting solution is clamp-oned tubular type doughnut spinning nozzle; Under the spinning speed of 15-60m/min; Casting solution is extruded by air pressure, gets into the spinning head casting solution through strainer filtering and measuring pump and gets into the hole, and gets into the hole from monfil and gets into the monfil of spinning head and get into deionized water the hole film-forming that after entering coagulating bath after the spinning head generation composite molding, is separated with core liquid; The coagulating bath gel media is the water of steady temperature, and coolant-temperature gage is controlled at 18-45 ℃.Spinning temperature 40-90 ℃, room temperature 18-25 ℃, indoor humidity 6-70%.
Described pore former is: polyethylene glycol or polyvinylpyrrolidone.Described solvent is: N, N-dimethylacetylamide or N, dinethylformamide.
The present invention's beneficial effect compared with prior art is:
1) the physics hot strength is high: because the monfil booster action as reinforcing bar is arranged, the physics hot strength of this product is minimum can be increased more than the several times, and can increase the next doughnut film strength that further increases of quantity of monfil.Usually 3-4 root monfil longitudinal tensile strength can reach more than 1 kgf;
2) membrane material can not peel off: adopt the blending hollow-fibre membrane of kernmantle, coating and kernmantle easy separation are peeled off, and lose filtering function; And adopt this product, because monfil and bulk material have certain compatibility, and, can not take place to separate and peel off, the service life of the film that increases greatly fully by PVC bulk material parcel;
3) cost is lower than the blending hollow-fibre membrane of kernmantle: in the blending hollow-fibre membrane material cost of kernmantle the kernmantle cost to account for over half, so cost will double above than this product;
4) loading density is higher than the blending hollow-fibre membrane of kernmantle, reduces volume, reduces the filter plant cost.The blending hollow-fibre membrane of kernmantle is owing to receive the external diameter size restriction of kernmantle, and often thicker, external diameter is generally more than 2 millimeters; And this product does not have this restriction; External diameter can be accomplished 1.2 millimeters, and the membrane area of unit volume can increase like this, reduces the filter plant volume;
5) because the monofilament of introducing has certain intermiscibility with membrane material, and the volume that is embedded in the film is little, only accounts for the 3-5% of membrane material volume, and is very little to the film forming structure influence, so the water flux of film can reach 200L/m
2H, 0.1MPa, 25 ℃ is more than 2 times of kernmantle structural membrane, suitable with no support hollow tunica fibrosa.
Description of drawings
Fig. 1 is the polyvinyl chloride membrane preparation method schematic flow sheet of band backing material;
Fig. 2 is blending PVC hollow fiber membrane generalized section and existing two types of PVC hollow fiber membrane generalized sections.
The specific embodiment
The polychloroethylene film of band backing material is: with the filter membrane of pvc material and 3 parallel blending formation of above monfil; Monfil is evenly distributed on the rete center after the film forming; Monfil is spandex, nylon 6 or polyurethane, and the diameter of monfil is the 0.01-2 millimeter.
The preparation method's of the polychloroethylene film of band backing material step is following:
1) concentration is the polyvinyl chloride of 13-19 wt/v %; Concentration is that 1-3 wt/v % hydrophilizing agent polymethyl methacrylate, concentration are the pore former of 4-15 wt/v %; Concentration is that the solvent of 55-80 wt/v % adds in the molten material still successively; The hurdle is pressed in the shaft sealing of open dissolving the material still, stirs under 40-90 ℃, obtains casting solution;
2) casting solution is clamp-oned tubular type doughnut spinning nozzle; Under the spinning speed of 15-60m/min; Casting solution is extruded by air pressure, gets into the spinning head casting solution through strainer filtering and measuring pump and gets into the hole, and gets into the hole from monfil and gets into the monfil of spinning head and get into deionized water the hole film-forming that after entering coagulating bath after the spinning head generation composite molding, is separated with core liquid; The coagulating bath gel media is the water of steady temperature, and coolant-temperature gage is controlled at 18-45 ℃.Spinning temperature 40-90 ℃, room temperature 18-25 ℃, indoor humidity 6-70%.
Described pore former is: polyethylene glycol or polyvinylpyrrolidone.Described solvent is: N, N-dimethylacetylamide or N, dinethylformamide.
Embodiment 1
1) concentration is the polyvinyl chloride of 13 wt/v %; Concentration is that 1 wt/v % hydrophilizing agent polymethyl methacrylate, concentration are the polyethylene glycol of 4 wt/v %; Concentration is 55 wt/v %'s: N, N-dimethylacetylamide add in the molten material still successively, and the shaft of opening molten material still seals presses the hurdle; Stir under 40 ℃, obtain casting solution;
2) casting solution is clamp-oned tubular type doughnut spinning nozzle; Under the spinning speed of 15m/min; Casting solution is extruded by air pressure, gets into the spinning head casting solution through strainer filtering and measuring pump and gets into the hole, and gets into the hole from monfil and gets into the monfil of spinning head and get into deionized water the hole film-forming that after entering coagulating bath after the spinning head generation composite molding, is separated with core liquid; The coagulating bath gel media is the water of steady temperature, and coolant-temperature gage is controlled at 18 ℃.40 ℃ of spinning temperatures, 18 ℃ of room temperatures, indoor humidity 6%.
Structure of the present invention is similar to reinforced concrete structure, and PVC is equivalent to concrete, and the monfil reinforcement is equivalent to reinforcing bar, forms quantity (common more than 3) and intensity that whole back physics hot strength depends on monfil, and the PVC material plays filtering function.
Embodiment 2
1) concentration is the polyvinyl chloride of 19 wt/v %; Concentration is that 3 wt/v % hydrophilizing agent polymethyl methacrylates, concentration are the polyvinylpyrrolidone of 15 wt/v %; Concentration is the N of 80 wt/v %, and dinethylformamide adds to dissolve successively expects in the still, opens the shaft sealing pressure hurdle that dissolves the material still; Stir under 90 ℃, obtain casting solution;
2) casting solution is clamp-oned tubular type doughnut spinning nozzle; Under the spinning speed of 60m/min; Casting solution is extruded by air pressure, gets into the spinning head casting solution through strainer filtering and measuring pump and gets into the hole, and gets into the hole from monfil and gets into the monfil of spinning head and get into deionized water the hole film-forming that after entering coagulating bath after the spinning head generation composite molding, is separated with core liquid; The coagulating bath gel media is the water of steady temperature, and coolant-temperature gage is controlled at 45 ℃.90 ℃ of spinning temperatures, 25 ℃ of room temperatures, indoor humidity 70%.
Structure of the present invention is similar to reinforced concrete structure, and PVC is equivalent to concrete, and the monfil reinforcement is equivalent to reinforcing bar, forms quantity (common more than 3) and intensity that whole back physics hot strength depends on monfil, and the PVC material plays filtering function.
Embodiment 3
The resin-oatmeal 15 wt/v % of polyvinyl chloride; Polymethyl methacrylate 3 wt/v %; Polyvinylpyrrolidone (PVP), concentration are 8 wt/v %; N, N-dimethylacetylamide 75 wt/v %.Under 65 ℃ of temperature, stirred 12 hours, standing and defoaming 8 hours is equipped with hollow fiber ultrafiltration membrane through dry-jet wet-spinning silk legal system, and the air gap height is 15cm, and spinning speed is 40m/min.Add 3 on nylon 6 monofilament, inside and outside coagulating bath is 30 ℃ of water.Preparation gained film soaks the back test through rinsing and 60% glycerine.
Structure of the present invention is similar to reinforced concrete structure, and PVC is equivalent to concrete, and the monfil reinforcement is equivalent to reinforcing bar, forms quantity (common more than 3) and intensity that whole back physics hot strength depends on monfil, and the PVC material plays filtering function.
Embodiment 4
The resin-oatmeal 13 wt/v % of polyvinyl chloride; Polymethyl methacrylate 3 wt/v %; Polyethylene glycol, concentration are 15 wt/v %; N, dinethylformamide 75 wt/v %.Under 65 ℃ of temperature, stirred 12 hours, standing and defoaming 8 hours is equipped with hollow fiber ultrafiltration membrane through dry-jet wet-spinning silk legal system, and the air gap height is 15cm, and spinning speed is 40m/min.Add 3 on nylon 6 monofilament, inside and outside coagulating bath is 30 ℃ of water.Preparation gained film soaks the back test through rinsing and 60% glycerine.
Because this product physics hot strength is high; Membrane material is incrust; Manufacturing cost and water flux are suitable with no supporter hollow-fibre membrane, can replace existing two types of hollow-fibre membranes (the blending hollow-fibre membrane of no supporter hollow-fibre membrane, kernmantle) fully; Be specially:
Adopt the Hollow Fiber Ultrafiltration assembly or the MBR membrane bioreactor of this production to compare, owing to do not exist fracture of wire problem, filter effect can guarantee that can significantly prolong service life with no supporter hollow-fibre membrane.
Such as: the MBR diaphragm that same 20 square metres hollow-fibre membrane is processed uses in sewage, because physics chemical action such as aeration cleanings, no supporter doughnut film-strength is low; Be prone to fracture of wire, indexs such as effluent quality turbidity can continue variation, and the general life-span can only arrive 3 years; And adopt this product, because the supporter effect, intensity is high; Can fracture of wire, indexs such as effluent quality turbidity are stable, and the life-span can reach more than 5 years.To effluent quality require high, filter effect is stable, occasion advantage long service life is obvious more.
Embodiment 5
The resin-oatmeal 19 wt/v % of polyvinyl chloride; Polymethyl methacrylate 2 wt/v %; Polyethylene glycol, concentration are 15 wt/v %; N, N-dimethylacetylamide 80 wt/v %.Under 65 ℃ of temperature, stirred 12 hours, standing and defoaming 8 hours is equipped with hollow fiber ultrafiltration membrane through dry-jet wet-spinning silk legal system, and the air gap height is 15cm, and spinning speed is 40m/min.Add 3 on nylon 6 monofilament, inside and outside coagulating bath is 30 ℃ of water.Preparation gained film soaks the back test through rinsing and 60% glycerine.
Adopt the Hollow Fiber Ultrafiltration assembly or the MBR membrane bioreactor of this production to compare for the kernmantle hollow-fibre membrane with supporter, volume is little, and film can not peel off damage, long service life, and cost of investment and use cost can significantly reduce.
Such as: the MBR diaphragm that same 20 square metres hollow-fibre membrane is processed uses in sewage; Adopt the blending hollow-fibre membrane of kernmantle, volume needs 0.5 cubic metre, and adopts this product only to need 0.2 cubic metre; Equipment volume is little; Film can not peel off, and can prolong service life, and equipment investment cost can significantly reduce.
At last, what need particularly point out is that what more than to enumerate only is practical implementation case of the present invention.Obviously, the invention is not restricted to above-mentioned case study on implementation, can also many combinations.The all scenario that those of ordinary skill in the art can directly derive or associate from content disclosed by the invention all should be thought protection scope of the present invention.
Claims (4)
1. polychloroethylene film with backing material; It is characterized in that filter membrane with pvc material and 3 parallel blending formation of above monfil; Monfil is evenly distributed on the rete center after the film forming; Monfil is spandex, nylon 6 or polyurethane, and the diameter of monfil is the 0.01-2 millimeter.
2. the preparation method of an a kind of polychloroethylene film with backing material as claimed in claim 1 is characterized in that its step is following:
1) concentration is the polyvinyl chloride of 13-19 wt/v %; Concentration is that 1-3 wt/v % hydrophilizing agent polymethyl methacrylate, concentration are the pore former of 4-15 wt/v %; Concentration is that the solvent of 55-80 wt/v % adds in the molten material still successively; The hurdle is pressed in the shaft sealing of open dissolving the material still, stirs under 40-90 ℃, obtains casting solution;
2) casting solution is clamp-oned tubular type doughnut spinning nozzle; Under the spinning speed of 15-60m/min, casting solution is extruded by air pressure, gets into spinning head casting solution entering hole through strainer filtering and measuring pump; With get into the hole from monfil and get into the monfil of spinning head and get into deionized water the hole film-forming that after getting into coagulating bath after the spinning head generation composite molding, is separated with core liquid; The coagulating bath gel media is the water of steady temperature, and coolant-temperature gage is controlled at 18-45 ℃, spinning temperature 40-90 ℃; Room temperature 18-25 ℃, indoor humidity 6-70%.
3. the preparation method of a kind of polychloroethylene film with backing material according to claim 2 is characterized in that described pore former is: polyethylene glycol or polyvinylpyrrolidone.
4. the preparation method of a kind of polychloroethylene film with backing material according to claim 2 is characterized in that described solvent is: N, N-dimethylacetylamide or N, dinethylformamide.
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| CN2011102921568A CN102343220A (en) | 2011-09-29 | 2011-09-29 | Polyvinyl chloride membrane with supporting materials and preparation method thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102926197A (en) * | 2012-11-15 | 2013-02-13 | 杭州水处理技术研究开发中心有限公司 | Manufacturing method of support cloth for preparation of ion exchange membrane |
| CN102941025A (en) * | 2012-11-20 | 2013-02-27 | 浙江理工大学 | Preparation method of teflon hollow fiber membrane for membrane distillation |
| CN104088032A (en) * | 2014-06-30 | 2014-10-08 | 太仓天龙化纤有限公司 | Healthcare stretch yarn |
| CN104548960A (en) * | 2014-11-05 | 2015-04-29 | 华文蔚 | Preparation method of hollow fibrous polyvinyl chloride resin microporous membrane |
| CN107198974A (en) * | 2017-07-03 | 2017-09-26 | 四川恒创博联科技有限责任公司 | A kind of photocatalysis hollow fiber ultrafiltration membrane and preparation method thereof |
| CN113813799A (en) * | 2021-09-13 | 2021-12-21 | 上海海若环境集团有限公司 | Preparation method of PVDF ultrafiltration membrane with polyester lining |
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| CN1966132A (en) * | 2005-11-15 | 2007-05-23 | 深圳市诚德来实业有限公司 | PVC hollow fiber ultrafiltration membrane preparation method |
| CN102188911A (en) * | 2011-05-10 | 2011-09-21 | 浙江开创环保科技有限公司 | Polyvinylidene hollow fiber membrane with filament support material and preparation method thereof |
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- 2011-09-29 CN CN2011102921568A patent/CN102343220A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1966132A (en) * | 2005-11-15 | 2007-05-23 | 深圳市诚德来实业有限公司 | PVC hollow fiber ultrafiltration membrane preparation method |
| CN102188911A (en) * | 2011-05-10 | 2011-09-21 | 浙江开创环保科技有限公司 | Polyvinylidene hollow fiber membrane with filament support material and preparation method thereof |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102926197A (en) * | 2012-11-15 | 2013-02-13 | 杭州水处理技术研究开发中心有限公司 | Manufacturing method of support cloth for preparation of ion exchange membrane |
| CN102926197B (en) * | 2012-11-15 | 2014-05-07 | 杭州水处理技术研究开发中心有限公司 | Manufacturing method of support cloth for preparation of ion exchange membrane |
| CN102941025A (en) * | 2012-11-20 | 2013-02-27 | 浙江理工大学 | Preparation method of teflon hollow fiber membrane for membrane distillation |
| CN104088032A (en) * | 2014-06-30 | 2014-10-08 | 太仓天龙化纤有限公司 | Healthcare stretch yarn |
| CN104548960A (en) * | 2014-11-05 | 2015-04-29 | 华文蔚 | Preparation method of hollow fibrous polyvinyl chloride resin microporous membrane |
| CN107198974A (en) * | 2017-07-03 | 2017-09-26 | 四川恒创博联科技有限责任公司 | A kind of photocatalysis hollow fiber ultrafiltration membrane and preparation method thereof |
| CN113813799A (en) * | 2021-09-13 | 2021-12-21 | 上海海若环境集团有限公司 | Preparation method of PVDF ultrafiltration membrane with polyester lining |
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