CN117323844A - High-toughness chlorine-containing copolymer-based filtering membrane and preparation method thereof - Google Patents
High-toughness chlorine-containing copolymer-based filtering membrane and preparation method thereof Download PDFInfo
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- CN117323844A CN117323844A CN202311404622.6A CN202311404622A CN117323844A CN 117323844 A CN117323844 A CN 117323844A CN 202311404622 A CN202311404622 A CN 202311404622A CN 117323844 A CN117323844 A CN 117323844A
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- vinyl chloride
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- 239000012528 membrane Substances 0.000 title claims abstract description 146
- 229920001577 copolymer Polymers 0.000 title claims abstract description 73
- 238000001914 filtration Methods 0.000 title claims abstract description 60
- 238000002360 preparation method Methods 0.000 title claims abstract description 57
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 239000000460 chlorine Substances 0.000 title claims abstract description 46
- 229910052801 chlorine Inorganic materials 0.000 title claims abstract description 46
- 238000000034 method Methods 0.000 claims abstract description 26
- 239000007788 liquid Substances 0.000 claims abstract description 24
- 229920002554 vinyl polymer Polymers 0.000 claims abstract description 12
- 238000006243 chemical reaction Methods 0.000 claims abstract description 11
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 claims abstract description 11
- -1 poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate Chemical compound 0.000 claims description 31
- 239000012510 hollow fiber Substances 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical group O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical group CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 15
- 239000002904 solvent Substances 0.000 claims description 15
- VLDPXPPHXDGHEW-UHFFFAOYSA-N 1-chloro-2-dichlorophosphoryloxybenzene Chemical compound ClC1=CC=CC=C1OP(Cl)(Cl)=O VLDPXPPHXDGHEW-UHFFFAOYSA-N 0.000 claims description 14
- 239000000463 material Substances 0.000 claims description 12
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 11
- SQNNHEYXAJPPKH-UHFFFAOYSA-N chloroethene;prop-2-enoic acid Chemical compound ClC=C.OC(=O)C=C SQNNHEYXAJPPKH-UHFFFAOYSA-N 0.000 claims description 10
- 238000001035 drying Methods 0.000 claims description 10
- 239000000126 substance Substances 0.000 claims description 8
- 239000002202 Polyethylene glycol Substances 0.000 claims description 7
- 239000008367 deionised water Substances 0.000 claims description 7
- 229910021641 deionized water Inorganic materials 0.000 claims description 7
- 229920001223 polyethylene glycol Polymers 0.000 claims description 7
- 239000011148 porous material Substances 0.000 claims description 7
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims description 6
- GCTFWCDSFPMHHS-UHFFFAOYSA-M Tributyltin chloride Chemical compound CCCC[Sn](Cl)(CCCC)CCCC GCTFWCDSFPMHHS-UHFFFAOYSA-M 0.000 claims description 5
- 230000001112 coagulating effect Effects 0.000 claims description 5
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 4
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 4
- 238000007664 blowing Methods 0.000 claims description 4
- 239000012760 heat stabilizer Substances 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 229920000139 polyethylene terephthalate Polymers 0.000 claims description 4
- 239000005020 polyethylene terephthalate Substances 0.000 claims description 4
- 229920002215 polytrimethylene terephthalate Polymers 0.000 claims description 4
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 4
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 4
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 4
- 238000003756 stirring Methods 0.000 claims description 4
- OMIGHNLMNHATMP-UHFFFAOYSA-N 2-hydroxyethyl prop-2-enoate Chemical group OCCOC(=O)C=C OMIGHNLMNHATMP-UHFFFAOYSA-N 0.000 claims description 3
- CQEYYJKEWSMYFG-UHFFFAOYSA-N butyl acrylate Chemical group CCCCOC(=O)C=C CQEYYJKEWSMYFG-UHFFFAOYSA-N 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 3
- 239000000178 monomer Substances 0.000 claims description 3
- ZBBLRPRYYSJUCZ-GRHBHMESSA-L (z)-but-2-enedioate;dibutyltin(2+) Chemical compound [O-]C(=O)\C=C/C([O-])=O.CCCC[Sn+2]CCCC ZBBLRPRYYSJUCZ-GRHBHMESSA-L 0.000 claims description 2
- QZPSOSOOLFHYRR-UHFFFAOYSA-N 3-hydroxypropyl prop-2-enoate Chemical compound OCCCOC(=O)C=C QZPSOSOOLFHYRR-UHFFFAOYSA-N 0.000 claims description 2
- ISKQADXMHQSTHK-UHFFFAOYSA-N [4-(aminomethyl)phenyl]methanamine Chemical compound NCC1=CC=C(CN)C=C1 ISKQADXMHQSTHK-UHFFFAOYSA-N 0.000 claims description 2
- UKLDJPRMSDWDSL-UHFFFAOYSA-L [dibutyl(dodecanoyloxy)stannyl] dodecanoate Chemical compound CCCCCCCCCCCC(=O)O[Sn](CCCC)(CCCC)OC(=O)CCCCCCCCCCC UKLDJPRMSDWDSL-UHFFFAOYSA-L 0.000 claims description 2
- XQBCVRSTVUHIGH-UHFFFAOYSA-L [dodecanoyloxy(dioctyl)stannyl] dodecanoate Chemical compound CCCCCCCCCCCC(=O)O[Sn](CCCCCCCC)(CCCCCCCC)OC(=O)CCCCCCCCCCC XQBCVRSTVUHIGH-UHFFFAOYSA-L 0.000 claims description 2
- 229920006231 aramid fiber Polymers 0.000 claims description 2
- CJZGTCYPCWQAJB-UHFFFAOYSA-L calcium stearate Chemical compound [Ca+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CJZGTCYPCWQAJB-UHFFFAOYSA-L 0.000 claims description 2
- 235000013539 calcium stearate Nutrition 0.000 claims description 2
- 239000008116 calcium stearate Substances 0.000 claims description 2
- 239000012975 dibutyltin dilaurate Substances 0.000 claims description 2
- YAHBZWSDRFSFOO-UHFFFAOYSA-L dimethyltin(2+);2-(2-ethylhexoxy)-2-oxoethanethiolate Chemical compound CCCCC(CC)COC(=O)CS[Sn](C)(C)SCC(=O)OCC(CC)CCCC YAHBZWSDRFSFOO-UHFFFAOYSA-L 0.000 claims description 2
- LNMQRPPRQDGUDR-UHFFFAOYSA-N hexyl prop-2-enoate Chemical compound CCCCCCOC(=O)C=C LNMQRPPRQDGUDR-UHFFFAOYSA-N 0.000 claims description 2
- 229940065472 octyl acrylate Drugs 0.000 claims description 2
- ANISOHQJBAQUQP-UHFFFAOYSA-N octyl prop-2-enoate Chemical compound CCCCCCCCOC(=O)C=C ANISOHQJBAQUQP-UHFFFAOYSA-N 0.000 claims description 2
- 229920005594 polymer fiber Polymers 0.000 claims description 2
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical group [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 claims description 2
- 125000006160 pyromellitic dianhydride group Chemical group 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 15
- 230000004907 flux Effects 0.000 abstract description 13
- 238000004132 cross linking Methods 0.000 abstract description 9
- 239000000654 additive Substances 0.000 abstract 1
- 230000000996 additive effect Effects 0.000 abstract 1
- 238000001891 gel spinning Methods 0.000 abstract 1
- 239000004800 polyvinyl chloride Substances 0.000 description 28
- 229920000915 polyvinyl chloride Polymers 0.000 description 27
- 238000012512 characterization method Methods 0.000 description 12
- 238000000108 ultra-filtration Methods 0.000 description 9
- 239000003999 initiator Substances 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- 238000009472 formulation Methods 0.000 description 7
- 238000006116 polymerization reaction Methods 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 239000002270 dispersing agent Substances 0.000 description 6
- 238000009864 tensile test Methods 0.000 description 6
- 238000012986 modification Methods 0.000 description 5
- 230000004048 modification Effects 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- 239000002253 acid Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000011049 filling Methods 0.000 description 3
- 238000002715 modification method Methods 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 241000894006 Bacteria Species 0.000 description 2
- 239000002033 PVDF binder Substances 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 229920003235 aromatic polyamide Polymers 0.000 description 2
- NMJJFJNHVMGPGM-UHFFFAOYSA-N butyl formate Chemical compound CCCCOC=O NMJJFJNHVMGPGM-UHFFFAOYSA-N 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 229920000578 graft copolymer Polymers 0.000 description 2
- 239000003607 modifier Substances 0.000 description 2
- 239000002077 nanosphere Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000012745 toughening agent Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- CBCKQZAAMUWICA-UHFFFAOYSA-N 1,4-phenylenediamine Chemical compound NC1=CC=C(N)C=C1 CBCKQZAAMUWICA-UHFFFAOYSA-N 0.000 description 1
- FERIUCNNQQJTOY-UHFFFAOYSA-M Butyrate Chemical compound CCCC([O-])=O FERIUCNNQQJTOY-UHFFFAOYSA-M 0.000 description 1
- 239000004801 Chlorinated PVC Substances 0.000 description 1
- 229920000459 Nitrile rubber Polymers 0.000 description 1
- 229920006243 acrylic copolymer Polymers 0.000 description 1
- 229920000122 acrylonitrile butadiene styrene Polymers 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 239000004760 aramid Substances 0.000 description 1
- 238000010560 atom transfer radical polymerization reaction Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- FYXKZNLBZKRYSS-UHFFFAOYSA-N benzene-1,2-dicarbonyl chloride Chemical compound ClC(=O)C1=CC=CC=C1C(Cl)=O FYXKZNLBZKRYSS-UHFFFAOYSA-N 0.000 description 1
- 230000003115 biocidal effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 229920000457 chlorinated polyvinyl chloride Polymers 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000010612 desalination reaction Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000001471 micro-filtration Methods 0.000 description 1
- 239000002121 nanofiber Substances 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- 238000005502 peroxidation Methods 0.000 description 1
- 238000000614 phase inversion technique Methods 0.000 description 1
- 239000002798 polar solvent Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 235000019422 polyvinyl alcohol Nutrition 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000010557 suspension polymerization reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 229920001897 terpolymer Polymers 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/44—Polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds, not provided for in a single one of groups B01D71/26-B01D71/42
-
- 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
- B01D67/0006—Organic membrane manufacture by chemical reactions
-
- 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
- B01D2325/24—Mechanical properties, e.g. strength
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/36—Hydrophilic membranes
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a high-toughness chlorine-containing copolymer-based filtering membrane and a preparation method thereof. The main component of the high-toughness chlorine-containing copolymer-based filtering membrane is a chloroethylene-acrylic ester copolymer and a cross-linked product thereof. The preparation method of the high-toughness chlorine-containing copolymer-based filtering membrane comprises the following steps: and (3) curing and forming the film-forming liquid containing the vinyl chloride-acrylic ester copolymer and the additive thereof by a dry-wet spinning process, and performing partial crosslinking reaction after curing and forming. The prepared chlorine-containing copolymer-based filtering membrane has the advantages of high toughness, high aperture ratio, large flux, simple preparation process and the like.
Description
Technical Field
The invention belongs to the technical field of membrane separation, and particularly relates to a high-toughness chlorine-containing copolymer-based filtering membrane and a preparation method thereof.
Background
The membrane separation technology has the advantages of high efficiency, simple equipment, convenient operation, energy conservation, environmental protection and the like, and has great application potential in the industrial field, and the application range of the membrane separation technology is expanded to the fields of biology, medicine, environmental protection, energy, sea water desalination, wastewater treatment and the like.
Polyvinyl chloride (PVC) is one of three important synthetic resins with the largest yield, has rich sources, low price, good chemical stability, bacteria resistance, acid and alkali resistance and chemical corrosion resistance, is widely applied to the preparation of ultrafiltration membranes and microfiltration membranes for water treatment, can be dissolved in various polar solvents, and has low membrane preparation cost. The research on polyvinyl chloride as a membrane material and a preparation method thereof is reported both at home and abroad. The comparison is typically: chinese patent (CN 1579600A) reports a polyvinyl chloride/vinyl chloride-vinyl acetate-maleic anhydride terpolymer alloy hollow filtration membrane and a preparation method thereof. Chinese patent (CN 101195084A) reports a self-assembled hydrophilization modification method for PVC alloy ultrafiltration membrane surface, and PVC membrane flux reaches 1000L/m 2 h. Chinese patent (CN 200810062570.8) discloses a preparation method of a hydrophilic polyvinyl chloride alloy ultrafiltration membrane. The amphiphilic graft copolymer of polyvinyl chloride is synthesized by an atom transfer radical polymerization method, and the amphiphilic graft copolymer is used as a hydrophilic modifier to be blended with the polyvinyl chloride, so that the polyvinyl chloride alloy ultrafiltration membrane with controllable structure, hydrophilicity, pollution resistance, large flux and high retention rate is prepared by a solution phase conversion method. A series of Chinese patent (CN201811062841. X, CN201811063844.5, CN201811062838.8, CN201810191903.0, CN201410730313.2, CN201510057782.7, CN201510058518.5, CN201510059113.3, CN 201410734459.4) pairs adopts vinyl chloride copolymer orThe modified PVC is used for preparing the membrane, and the membrane has different chemical structures and membrane performances, and mainly aims at innovatively inventing the performances of interception substances, membrane hydrophilicity, membrane antibiosis, pollution resistance and the like, expanding the application range of the chlorine-containing polymer filter membrane and prolonging the service life of the chlorine-containing polymer filter membrane.
However, PVC is a rigid material, and the application range is greatly limited due to insufficient toughness. As a matter of course, as a filtration membrane material, it is easy to cause cracking or breaking of membrane filaments during use, particularly in a state of intense aeration for a long period of time. Therefore, the preparation of the chlorine-containing polymer filtering membrane with high toughness and high flux has important significance through a certain modification method. For toughening modification of PVC, the main research direction is toughening modification in the aspect of PVC profile preparation, which comprises means of nanoparticle filling, elastomer material compounding, inorganic nanofiber reinforcement and the like. However, due to the special preparation of the filtering membrane by the phase inversion method, the modifier used is required to have better solubility and compatibility in the membrane preparation liquid, so the toughening modification method for the PVC filtering membrane is very limited. Chinese patent (CN 112999893A) discloses a PVC composite ultrafiltration membrane prepared by dispersing synthetic para-aramid nanospheres in a PVC matrix, wherein compared with a pure PVC ultrafiltration membrane, the mechanical properties of the PVC composite ultrafiltration membrane are greatly improved, but the step of synthesizing the aramid nanospheres by adopting phthaloyl chloride and p-phenylenediamine is very complicated, and the PVC composite ultrafiltration membrane is difficult to apply in large scale. Chinese patent (CN 200810189737.7) discloses an ultrafiltration membrane blended by PVDF and PVC and a preparation method thereof, wherein the adopted toughening agent is chlorinated polyvinyl chloride, nitrile rubber, polyurethane, ABS and the like, and the toughening agent is not added for toughening modification of PVC because the toughness of PVDF is very excellent.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a high-toughness chlorine-containing copolymer-based filtering membrane and a preparation method thereof. Different from the existing filtering membrane materials and the preparation technology thereof, the invention discloses a high-toughness chlorine-containing copolymer-based filtering membrane and a preparation method thereof. The disclosed high-toughness chlorine-containing copolymer-based filtering membrane has the advantages of good toughness, stable structure and performance, high aperture ratio, large flux and the like, is suitable for various membrane water treatment equipment and projects, and the disclosed preparation method has the characteristics of strong controllability of membrane structure and performance, simple process, low manufacturing cost and the like in the preparation process.
The technical scheme of the invention is as follows:
the invention firstly provides a preparation method of a high-toughness chlorine-containing copolymer-based filtering membrane, which comprises the following steps:
1) Mixing 20-40% by weight of vinyl chloride-acrylic ester copolymer, 1-5% by weight of pore size regulator, 0.1-1% by weight of heat stabilizer and 55-75% by weight of solvent, stirring and dissolving at 50-70 ℃ to obtain uniform film-forming liquid; the pore diameter regulator is polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) or glycerol;
2) Extruding the film-forming liquid from a spinneret to form a tubular liquid film, uniformly wrapping around a substance in a central tube of the spinneret, and vertically entering a coagulating bath to solidify into a hollow fiber film after passing through an air gap of 0-20 cm; the material in the central tube of the spinneret is deionized water or a supporting tube;
3) And (3) passing the hollow fiber membrane solidified in the solidifying bath in the step (2) through a blowing drying channel at 40-55 ℃ for 30-60s, drying the surface of the membrane, immersing in pyromellitic dianhydride solution, continuing to pass through the blowing drying channel at 40-55 ℃ for 10-30s, and rinsing with water to obtain the high-toughness chlorine-containing copolymer-based filtering membrane.
Further, the vinyl chloride-acrylic acid ester copolymer is: one or more of poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate), poly (vinyl chloride-hexyl acrylate-hydroxyethyl acrylate), poly (vinyl chloride-octyl acrylate-hydroxyethyl acrylate), poly (vinyl chloride-butyl acrylate-hydroxypropyl acrylate), poly (vinyl chloride-hexyl acrylate-hydroxypropyl acrylate), or poly (vinyl chloride-octyl acrylate-hydroxypropyl acrylate).
Further, the vinyl chloride-acrylic acid ester copolymer comprises the following monomer components: 50-80% by weight of vinyl chloride, 15-40% by weight of acrylic ester and 3-10% by weight of hydroxyalkyl acrylate; the acrylic ester is butyl acrylate, hexyl acrylate or octyl acrylate; the hydroxyalkyl acrylate is hydroxyethyl acrylate or hydroxypropyl acrylate.
Further, the number average molecular weight of the vinyl chloride-acrylic ester copolymer is 40,000-100,000Da.
Further, the heat stabilizer is zinc stearate, calcium stearate, tributyltin chloride, dibutyl tin diacetate, dibutyl tin maleate, methyl tin mercaptide, dibutyl tin dilaurate or di-n-octyl tin dilaurate; the solvent is N, N '-Dimethylformamide (DMF), N' -dimethylacetamide (DMAc) or N-methylpyrrolidone (NVP); the supporting tube is a polymer fiber braided tube, and the supporting tube is made of polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) or aramid fiber.
Further, the pyromellitic dianhydride solution comprises the following components: 30-60% of pyromellitic dianhydride and 40-70% of solvent; the solvent in the pyromellitic dianhydride solution is N, N '-Dimethylformamide (DMF), N' -dimethylacetamide (DMAc) or N-methylpyrrolidone (NVP).
Further, when the hollow fiber membrane is immersed in the pyromellitic dianhydride solution, the contact time with the pyromellitic dianhydride solution is 1-5s.
The invention also provides the high-toughness chlorine-containing copolymer-based filtering membrane prepared by the method.
Further, in the high-toughness chlorine-containing copolymer-based filtering membrane, the weight percentage of the vinyl chloride-acrylic ester copolymer is 95-99.5%, the weight percentage of the crosslinked product of the vinyl chloride and acrylic ester copolymer is 0.5-5%, and the crosslinked product of the vinyl chloride and acrylic ester copolymer is the product obtained by reacting the vinyl chloride-acrylic ester copolymer with pyromellitic dianhydride.
Compared with the prior art, the invention has the beneficial effects that:
the high-toughness chlorine-containing copolymer-based filtering membrane disclosed by the invention adopts a specific vinyl chloride-acrylic ester copolymer as a main base material, and has excellent toughness and softness due to a comonomer structure of a special chemical structure, so that the prepared filtering membrane completely overcomes the defects of poor toughness and easiness in cracking of a PVC filtering membrane, and has the advantages of bacteria resistance, acid and alkali resistance, chemical corrosion resistance and the like which are necessary for separating membrane materials;
in addition, the preparation method of the high-toughness chlorine-containing copolymer-based filtering membrane disclosed by the invention combines a one-step spinning solidification forming process of a tubular liquid membrane with a simple crosslinking process. The process is simple, the operation is convenient, the efficiency is high, the diversified pore structures can be obtained by changing fewer process parameters, the controllability of the membrane structure is good, and the production repeatability is good;
in addition, according to the preparation method of the high-toughness chlorine-containing copolymer-based filtering membrane disclosed by the invention, the outer surface of the filtering membrane is subjected to a crosslinking process to form a partially crosslinked product of the copolymer of vinyl chloride and acrylic esters; the pore structure of the film surface and the softness of the film surface can be regulated by the process, so that the toughness of the film is improved, the strength is increased, and the comprehensive mechanical property of the film is improved.
In addition, according to the preparation method of the high-toughness chlorine-containing copolymer-based filtering membrane disclosed by the invention, the outer surface of the filtering membrane is subjected to a crosslinking process to form a partially crosslinked product of the copolymer of vinyl chloride and acrylic esters; by the process, a small amount of carboxyl groups can be formed on the surface of the membrane, so that the hydrophilicity of the surface of the membrane is increased, and the pollution resistance of the membrane filaments can be enhanced.
In addition, the vinyl chloride-acrylic ester copolymer disclosed by the invention has low glass transition temperature, so that the arrangement of polymer molecules in the curing process is influenced, and the filtering membrane forms a very loose section structure, thereby greatly reducing the filtering resistance and increasing the flux. Secondly, the chloroethylene-acrylic ester copolymer has partial hydroxyl, firstly, the hydrophilicity of the surface of the film is increased, the pollution resistance of the film yarn is enhanced, and secondly, active sites of a crosslinking process are provided, so that the post-crosslinking process is carried out. Finally, the vinyl chloride-acrylic ester copolymer can not run off in the film making process and the using process, and the composition, physical structure and durable performance stability of the film are ensured.
Drawings
FIG. 1 is a schematic diagram of the structure of a vinyl chloride-acrylic acid ester copolymer of a high-toughness chlorine-containing copolymer-based filtration membrane;
FIG. 2 is a schematic diagram of the crosslinking reaction of vinyl chloride and acrylic copolymers and the structure of the products of the crosslinking reaction;
FIG. 3 is a SEM photograph of the surface of a sample of a high-toughness chlorine-containing copolymer-based filtration membrane.
Detailed Description
The present invention will be described in detail with reference to the following examples. The procedure for all examples was the same as that described above, with the parameters in the table being the various conditions of implementation and the resulting film structure and properties. It is noted that the described embodiments do not limit the present invention, and all modifications which can be directly derived or suggested to one skilled in the art from the disclosure of the present invention should be considered as the protection scope of the present invention.
The vinyl chloride-acrylic ester copolymer can be prepared by adopting polymerization modes such as suspension polymerization and the like, and the general method of the preparation method can be as follows: adding deionized water, a dispersing agent and an initiator into a polymerization kettle, vacuumizing, filling nitrogen for 3 times repeatedly, adding a solubilizer and a formula amount of vinyl chloride monomer, and pre-dispersing and stirring at room temperature. The temperature is raised to the polymerization temperature, and the comonomer (namely corresponding acrylic ester and hydroxyalkyl acrylate) with the formula amount is gradually dripped to carry out the polymerization reaction. When the reaction is finished, air is introduced into the system to terminate the reaction. Discharging, filtering, washing, extracting the solubilizer with methanol, and drying to obtain the vinyl chloride-acrylic ester copolymer. The preparation methods of different vinyl chloride-acrylic acid ester copolymers can be different in comonomer, dispersant, initiator, solubilizer, dripping time, reaction temperature and reaction time. The dispersing agent, the initiator and the solubilizer are all well known concepts in the polymerization field, the specific types and the adding amount of the dispersing agent and the initiator can be selected according to the needs, and the dispersing agent can be selected from: polyvinyl alcohols, hydroxycellulose, and the like; the initiator may be selected from: azo initiators, oil-soluble peroxidation initiators, and the like; the solubilizer may be selected from: alkyl acid esters such as propyl formate and butyl formate. The selection of the catalyst does not have essential influence on the product, and the invention is not particularly limited in the type and the addition amount. Taking poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate) as an example, the preparation method adopts the following steps: 2000ml deionized water, 1.2g dispersant solution and 1g initiator are added into a stainless steel reaction kettle, vacuum pumping and nitrogen filling are carried out repeatedly for 3 times, 1600g chloroethylene and 7.5g solubilizer are added, and the mixture is pre-dispersed and stirred for 30 minutes at room temperature. The temperature is raised to 50 ℃ for polymerization, 300g of butyl acrylate and 100g of hydroxyethyl acrylate are gradually added dropwise, and polymerization reaction is carried out. Dropwise adding for 4-6h, reacting for 12 h, and introducing air into the system to terminate the reaction. Discharging, filtering, washing, extracting the solubilizer with 500g of methanol, and drying at 50 ℃ to obtain the poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate).
Example 1.
The preparation steps, the structure and the performance characterization method of the high-toughness chlorine-containing copolymer-based filtering membrane are as follows:
1) 300g of poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate), 30g of polyethylene glycol, 5g of tributyl tin chloride and 6615 g of N, N' -Dimethylformamide (DMF) are mixed, stirred and dissolved for 24 hours at 67 ℃ to form uniform film-forming liquid, and vacuumized and defoamed for 2 hours;
2) Deionized water at 40 ℃ passes through a central tube of a spinneret, the membrane preparation liquid in the step 1) is extruded from the outer ring of the spinneret to form a tubular liquid membrane, and the liquid membrane vertically enters a coagulating bath at 40 ℃ to be solidified into a hollow fiber membrane after passing through an air gap of 10 cm;
3) And (3) passing the hollow fiber membrane solidified in the solidifying bath in the step (2) through a 40 ℃ air blast drying tunnel for 60s, immersing and passing through a DMF solution of pyromellitic dianhydride with the weight percentage of 30%, passing through the air blast drying tunnel for 30s for 5s, and rinsing with water to obtain the high-toughness chlorine-containing copolymer-based filtering membrane.
The characterization method of the structure and the performance of the high-toughness chlorine-containing copolymer-based filtering membrane comprises the following steps:
structural morphology of the film: the film microstructure was observed with a scanning electron microscope (femner), fig. 3.
Determination of film properties: 1 tensile test: selecting a high-toughness chlorine-containing copolymer-based filtering membrane, testing the tensile strength and the elongation at break by using a tensile machine, and taking an average value after 10 times of testing; 2 flux test, measuring pure water flux of the membrane under 0.1MPa pressure.
The formulation of the membrane preparation solution, the preparation conditions of the hollow fiber membrane and the membrane performance are shown in table 1.
TABLE 1
Example 2.
The preparation steps and the characterization methods of the structure and the performance of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in example 1:
the formulation of the membrane preparation solution, the preparation conditions of the hollow fiber membrane and the membrane performance are shown in Table 2.
TABLE 2
Example 3.
The preparation steps, structure and performance characterization methods of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in the example 1, and the membrane preparation liquid formula, the hollow fiber membrane preparation conditions and the membrane performance are shown in the table 3.
TABLE 3 Table 3
Example 4.
The preparation steps, structure and performance characterization method of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in example 1, and the tensile test data are mechanical properties of the support tube because the central tube material is the support tube. The formulation of the membrane preparation solution, the preparation conditions of the hollow fiber membrane and the membrane properties are shown in Table 4.
TABLE 4 Table 4
Example 5.
The preparation steps, structure and performance characterization method of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in example 1, and the tensile test data are mechanical properties of the support tube because the central tube material is the support tube. The formulation of the membrane preparation solution, the conditions for preparing the hollow fiber membrane and the membrane properties are shown in Table 5.
TABLE 5
Example 6.
The preparation steps, structure and performance characterization method of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in example 1, and the tensile test data are mechanical properties of the support tube because the central tube material is the support tube. The formulation of the membrane preparation solution, the conditions for preparing the hollow fiber membrane and the membrane properties are shown in Table 6.
TABLE 6
Example 7.
The preparation steps, structure and performance characterization methods of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in example 1, and the membrane preparation liquid formula, the hollow fiber membrane preparation conditions and the membrane performance are shown in Table 7.
TABLE 7
Example 8.
The preparation steps, structure and performance characterization methods of the high-toughness chlorine-containing copolymer-based filtration membrane are shown in example 1, and the membrane preparation liquid formula, the hollow fiber membrane preparation conditions and the membrane performance are shown in Table 8.
TABLE 8
Comparative example 1.
1) 300g of poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate), 30g of polyethylene glycol, 5g of tributyl tin chloride and 6615 g of N, N' -Dimethylformamide (DMF) are mixed, stirred and dissolved for 24 hours at 67 ℃ to form uniform film-forming liquid, and vacuumized and defoamed for 2 hours; the method comprises the steps of carrying out a first treatment on the surface of the
2) Deionized water at 40 ℃ passes through a central tube of a spinneret, the membrane preparation liquid in the step 1) is extruded from the outer ring of the spinneret to form a tubular liquid membrane, and the liquid membrane vertically enters a coagulating bath at 40 ℃ to be solidified into a hollow fiber membrane after passing through an air gap of 10 cm; and rinsing with water to obtain the high-toughness chlorine-containing copolymer-based filtering membrane.
The characterization method of the structure and the performance of the high-toughness chlorine-containing copolymer-based filtering membrane comprises the following steps:
determination of film properties: 1 tensile test: selecting a high-toughness chlorine-containing copolymer-based filtering membrane, testing the tensile strength and the elongation at break by using a tensile machine, and taking an average value after 10 times of testing; 2 flux test, measuring pure water flux of the membrane under 0.1MPa pressure.
The formulation of the membrane preparation solution, the conditions for preparing the hollow fiber membrane and the membrane properties are shown in Table 9.
In comparative example 1, the tensile strength of the resulting film was significantly reduced as compared with example 1, indicating that the crosslinking reaction is critical for maintaining the tensile strength.
TABLE 9
Comparative example 2.
The preparation steps, structure and performance characterization method of the PVC filter membrane are as follows:
1) Mixing 300g of polyvinyl chloride, 30g of polyethylene glycol, 5g of tributyl tin chloride and 665g of N, N' -Dimethylformamide (DMF), stirring and dissolving at 67 ℃ for 24 hours to form uniform film-forming liquid, and vacuumizing and defoaming for 2 hours; the method comprises the steps of carrying out a first treatment on the surface of the
2) Deionized water at 40 ℃ passes through a central tube of a spinneret, the membrane preparation liquid in the step 1) is extruded from the outer ring of the spinneret to form a tubular liquid membrane, and the liquid membrane vertically enters a coagulating bath at 40 ℃ to be solidified into a hollow fiber membrane after passing through an air gap of 10 cm; and rinsing with water to obtain the PVC-based filtering membrane.
The characterization method of the structure and the performance of the PVC-based filtering membrane comprises the following steps:
determination of film properties: 1 tensile test: selecting a PVC-based filtering film, testing the tensile strength and the breaking elongation by using a tensile machine, and taking an average value 10 times; 2 flux test, measuring pure water flux of the membrane under 0.1MPa pressure.
The formulation of the membrane preparation solution, the conditions for preparing the hollow fiber membrane and the membrane properties are shown in Table 10.
In comparative example 2, PVC was used as the membrane substrate, and the elongation at break and flux of the resulting membrane were significantly reduced as compared to example 1, indicating that the vinyl chloride-acrylic acid ester copolymer of the present invention plays a key toughening role and also plays an indispensable role in the formation of a loose pore structure.
Table 10
The foregoing examples illustrate only a few embodiments of the invention and are described in detail herein without thereby limiting the scope of the invention. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit of the invention.
Claims (9)
1. A preparation method of a high-toughness chlorine-containing copolymer-based filtering membrane is characterized by comprising the following steps:
1) Mixing 20-40% by weight of vinyl chloride-acrylic ester copolymer, 1-5% by weight of pore size regulator, 0.1-1% by weight of heat stabilizer and 55-75% by weight of solvent, stirring and dissolving at 50-70 ℃ to obtain uniform film-forming liquid; the pore diameter regulator is polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) or glycerol;
2) Extruding the film-forming liquid from a spinneret to form a tubular liquid film, uniformly wrapping around a substance in a central tube of the spinneret, and vertically entering a coagulating bath to solidify into a hollow fiber film after passing through an air gap of 0-20 cm; the material in the central tube of the spinneret is deionized water or a supporting tube;
3) And (3) passing the hollow fiber membrane solidified in the solidifying bath in the step (2) through a blowing drying channel at 40-55 ℃ for 30-60s, drying the surface of the membrane, immersing in pyromellitic dianhydride solution, continuing to pass through the blowing drying channel at 40-55 ℃ for 10-30s, and rinsing with water to obtain the high-toughness chlorine-containing copolymer-based filtering membrane.
2. The method for preparing a high-toughness chlorine-containing copolymer-based filtration membrane according to claim 1, wherein the vinyl chloride-acrylic acid ester copolymer is: one or more of poly (vinyl chloride-butyl acrylate-hydroxyethyl acrylate), poly (vinyl chloride-hexyl acrylate-hydroxyethyl acrylate), poly (vinyl chloride-octyl acrylate-hydroxyethyl acrylate), poly (vinyl chloride-butyl acrylate-hydroxypropyl acrylate), poly (vinyl chloride-hexyl acrylate-hydroxypropyl acrylate), or poly (vinyl chloride-octyl acrylate-hydroxypropyl acrylate).
3. The method for preparing a chlorine-containing copolymer-based filtration membrane with high toughness according to claim 1, wherein the vinyl chloride-acrylic acid ester copolymer has the monomer composition of: 50-80% by weight of vinyl chloride, 15-40% by weight of acrylic ester and 3-10% by weight of hydroxyalkyl acrylate; the acrylic ester is butyl acrylate, hexyl acrylate or octyl acrylate; the hydroxyalkyl acrylate is hydroxyethyl acrylate or hydroxypropyl acrylate.
4. The method for producing a chlorine-containing copolymer-based filtration membrane of claim 1, wherein the number average molecular weight of the vinyl chloride-acrylic acid ester copolymer is 40,000 to 100,000da.
5. The method for preparing a high-toughness chlorine-containing copolymer-based filtration membrane according to claim 1, wherein the heat stabilizer is zinc stearate, calcium stearate, tributyltin chloride, dibutyltin diacetate, dibutyltin maleate, methyl tin mercaptide, dibutyltin dilaurate or di-n-octyltin dilaurate; the solvent is N, N '-Dimethylformamide (DMF), N' -dimethylacetamide (DMAc) or N-methylpyrrolidone (NVP); the supporting tube is a polymer fiber braided tube, and the supporting tube is made of polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) or aramid fiber.
6. The method for preparing a high-toughness chlorine-containing copolymer-based filtration membrane according to claim 1, wherein the composition of the pyromellitic dianhydride solution is: 30-60% of pyromellitic dianhydride and 40-70% of solvent; the solvent in the pyromellitic dianhydride solution is N, N '-Dimethylformamide (DMF), N' -dimethylacetamide (DMAc) or N-methylpyrrolidone (NVP).
7. The method for producing a chlorine-containing copolymer-based filtration membrane of claim 1, wherein the contact time with the pyromellitic dianhydride solution when the hollow fiber membrane is immersed in the pyromellitic dianhydride solution is 1 to 5 seconds.
8. A high-toughness chlorine-containing copolymer-based filtration membrane prepared by the method of any one of claims 1-7.
9. The membrane of claim 8, wherein the weight percentage of the vinyl chloride-acrylic acid ester copolymer in the membrane is 95-99.5% and the weight percentage of the crosslinked product of the vinyl chloride and acrylic acid ester copolymer is 0.5-5%, and the crosslinked product of the vinyl chloride and acrylic acid ester copolymer is the product of the reaction of the vinyl chloride-acrylic acid ester copolymer and pyromellitic dianhydride.
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