JP2895705B2 - Mosaic charged membrane and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mosaic charged membrane, and more particularly to a mosaic charged membrane useful for separating electrolytes, separating non-electrolytes or desalting.

[0002]

2. Description of the Related Art Conventionally, a mosaic-charged membrane in which cationic and anionic polymers are alternately arranged can dialyze a low-molecular electrolyte through a membrane and cannot dialyze a non-electrolyte. It has a function and is expected to be used for desalination and desalination of seawater, for example, and various studies have been made. As a typical mosaic charged membrane, for example, a block copolymer of AC and BC in which the polymers of A and B are incompatible with each other but are blocked with the third polymer C is formed into a lamella or cylinder structure. Adjust both quantitatively to become
Thereafter, an anionic polymer and a cationic polymer are formed into an ultrathin film in a planar and mosaic form on a substrate having an anionic group and a cationic group introduced, or on an appropriate liquid-permeable support, and then an epitaxy method is formed thereon. Some have grown the same ionic polymer layer.

[0003]

[Problems to be solved by the invention]
By utilizing the phase separation of the two block copolymers, in order to form La Mela or cylindrical structure, because of the anisotropy in quantitative constraints and both the structure of both the mixing ratio of the cross-section of the membrane The different polymer layers alternately overlap, and it is technically difficult to connect the front and back of the membrane with the same polymer layer. Further, such a phase separation structure is anisotropic, and has a lamella structure or a cylinder structure. It is difficult to adjust the direction. Also, after such a structure is made,
Since a cationic group and an anionic group are introduced, the production process is complicated, and the reaction amount of these ionic groups is also limited. In the epitaxy method,
In order to grow each ionic polymer layer on the mosaic pattern, very strict control of the formation of the mosaic pattern ultrathin film and the growth of the film was required, and there was a problem in producing a large-area membrane. Also, in any of the conventional methods, the membrane formed is very thin and has low strength, and it has not been possible to form a relatively thick membrane having high strength and excellent performance. Accordingly, an object of the present invention is to provide a mosaic charged membrane which is useful for separation of electrolytes, separation of non-electrolytes or desalination in a simple process.
It is to provide a method of manufacturing .

[0004]

The above object is achieved by the present invention described below. That is, the present invention relates to at least one
Is a sphere with a diameter of 0.01 to 10 μm (spherical).
Polymers) and cationic polymers and anionic polymers
(1) when manufacturing a mosaic charged membrane from
Sphere of one ionic polymer and ionic of the other
Mixing with a linear polymer solution to form a cast film,
(2) Prepare a dispersion of spheres of different ionic polymers
To form a cast film by mixing the dispersion liquid.
On the surface of one ionic polymer sphere, the other
Core-shell chemically bonded with on-linear polymer
Cast polymer from mold polymer and destroy core, (4)
Dispersions of different ionic spheres are prepared respectively,
After mixing the dispersion to form a cast film, the gap is reduced to one.
Ionic polymer or monomer
In the case of the above, further polymerize, and (5) one ionic
After fixing the polymer sphere to the liquid-permeable support,
Monomer constituting the other ionic polymer in the gap
And polymerizing the monomer.
Method of manufacturing a mosaic charged membrane and the above method
A mosaic charged membrane prepared from a cationic polymer and an anionic polymer obtained by a method, wherein at least one polymer is a sphere having a diameter of 0.01 to 10 μm.

[0005]

By selectively forming at least one of a cationic polymer and an anionic polymer in a mosaic charged membrane into a sphere having a diameter of 0.01 to 10 μm, it is possible to selectively separate an electrolyte and a non-electrolyte and to provide a machine as a membrane. A mosaic charged membrane with improved mechanical strength and the like can be provided at low cost.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to preferred embodiments. The cationic polymer used in the present invention is a polymer having primary to tertiary amino groups or quaternary ammonium groups, or a salt group of these ionic groups. The anionic polymer is a polymer having a sulfonic acid group, a carboxylic acid group, or a salt group of these ionic groups. In the case of a salt group, for a cationic group, for example, an anion such as hydrochloric acid, sulfuric acid, phosphoric acid, or an organic acid is used, and for an anionic group, for example, a cation such as an alkali metal ion is used. used.

Examples of the cationic polymer include polyvinyl pyridine and quaternary compounds thereof, poly 2-hydroxy-3-methacryloxypropyltrimethylammonium chloride, polydimethylaminoethyl methacrylate, and diethylaminoethyl polymethacrylate (or a salt thereof). And the like, or a copolymer of a plurality of monomers constituting these polymers and a copolymer with other monomers. As the anionic polymer, poly 2-acryloylamino-2-methyl-1-propanesulfonic acid, poly-2-acryloylamino-2-propanesulfonic acid, polymethacryloyloxypropylsulfonic acid,
Polysulfopropyl methacrylate, poly 2-sulfoethyl methacrylate, polyvinyl sulfonic acid, polyacrylic acid, polystyrene-maleic acid copolymer (or a salt of the acid), or the like, or a copolymer of a plurality of monomers constituting these polymers And copolymers with other monomers.

As a method for converting a polymer into a sphere as described above, besides various conventionally known methods, for example, a method of depositing a sphere from a polymer solution, for example, soap-free polymerization, emulsion polymerization, suspension polymerization, reverse phase polymerization,
A polymerization method such as seed polymerization may be used. It may be preferable that the polymer sphere is crosslinked. Examples of the crosslinking agent used for crosslinking include divinylbenzene, methylenebisacrylamide, ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, and other acrylates and methacrylates having 3 to 4 functionalities. No. These crosslinking agents are used in an amount of 20 parts by weight per 100 parts by weight of the monomers constituting the polymer.
It is used in an amount of 0.5 parts by weight or less, preferably 0.5 to 10 parts by weight. In the present invention, the crosslinked sphere and the uncrosslinked sphere are preferably used in combination. The sphere used has a diameter of 0.01 to 10 μm, preferably 0.02 to 1 μm.

[0009] The mosaic charged membrane of the present invention is formed using at least one kind of the polymer sphere as described above, and a suitable liquid-permeable support may be used to reinforce the formed membrane. preferable. As such a liquid-permeable support, a woven fabric, a nonwoven fabric, a porous resin sheet,
A porous body such as a porous ceramic sintered body or a metal mesh is preferred. The thickness of these porous bodies is 0.01 to 5
00 μm, preferably 0.1 to 100 μm. In the method for producing a mosaic charged membrane of the present invention, at least one of the anionic polymer and the cationic polymer needs to be a sphere, and the other polymer does not necessarily have to be a sphere.

The method for producing the membrane of the present invention includes:
(1) a method in which one ionic polymer sphere is immobilized on a liquid-permeable support, and then the other ionic monomer is filled in gaps between the spheres to polymerize the monomer.
(2) one ionic polymer spheres and other ionic linear polymer solution by mixing a method of cast film (The "linear polymer" in the present invention, distinguished from the sphere to a word, it may be a polymer having a branched chain unless spheres), (3) dispersion of an ionic polymer spheres heterologous were respectively prepared, cast film by mixing the dispersions thereof how to, (4) the surface of one of the ionic polymer spheres and chemically coupled to form the other ionic linear polymer core - the shell polymer, cast film forming of this, the core method of destroying connecting the cores and (5) a dispersion of an ionic polymer spheres heterologous were prepared respectively, after cast film by mixing these, the gap or one ionic polymer Mo Filling mer, how to further polymerization when using monomers, (1) to (4) methods in any combination of methods thereof.

[0011] Two polymer spheres used in the above is preferably a combination of a sphere of uncrosslinked and spheres are crosslinked, after they were mixed by cast film, polymer spheres in the film with a solvent or pressure, etc. To ensure the connection of the same ions by destroying or deforming
Further, the mechanical strength of the film can be improved.

[0012]

Next, the present invention will be described more specifically with reference to examples. Example 1 9.7 parts of an aqueous dispersion of cross-linked poly 4-vinylpyridine sphere (solid content = 2.15% by weight, diameter of about 200 nm),
9.7 parts aqueous dispersion of uncrosslinked poly4-vinylpyridine spheres (solids = 2.34% by weight, diameter about 180 n)
m), an uncrosslinked copolymer of sodium styrenesulfonate and acrylamide (molar ratio 1: 1) in aqueous solution (solid content 10
Mixing 50 wt% glutaraldehyde aqueous solution wt%) and 7.4 parts, to cast film air dried on a Teflon. The membrane was allowed to stand in a methanol atmosphere for one day to form a film of uncrosslinked poly4 -vinylpyridine spheres. The film was then left in a saturated solution of hydrochloric acid for one day, washed with water and air-dried, and washed with iodobutane / The treatment was carried out in a methanol atmosphere, and then the nitrogen atom of 4-vinylpyridine was completely quaternized in a methyl iodide / methanol atmosphere.

[0013] The mosaic charged membrane obtained in this way maintains a film shape without a liquid-permeable support. The dialysis test of this membrane uses the device shown in FIG.
It was carried out. As a non-electrolyte in the container 1 0.05 mol% / l glucose and 20ml input respectively 0.05 mol / l potassium chloride aqueous solution as an electrolyte
Then, 40 ml of pure water is put in the container 2, and the two containers
The membrane of the present invention described above is sandwiched between
After stirring for 3 days, the electrolyte and non-
The concentration of each of the degradations was measured. The thickness of this membrane is about 150 μm, and its dialysis performance is shown in FIG.
As is clear from the results shown in FIG. 2, the membrane of the present invention had good separation performance of the electrolyte and the non-electrolyte.
In FIG. 2, a very small amount of glucose is dialyzed.
This is considered to have appeared as a measurement error. In any case, the electrolyte was dialyzed well, the non-electrolyte was hardly dialyzed, and the separation of the electrolyte and non-electrolyte was sufficient.
In addition, since the dialysis experiment shown in FIG. 2 is performed at atmospheric pressure, it takes a long time for dialysis of the electrolyte. By thinning and applying pressure, the dialysis time can be significantly reduced.

Example 2 Same uncrosslinked copolymer of sodium styrene sulfonate and acrylamide as used in Example 1 (molar ratio 1: 1)
Half of the aqueous solution was made up of sodium styrene sulfonate-styrene-acrylamide-divinylbenzene (molar ratio 50 /
The mosaic charged membrane of the present invention was produced in the same manner as in Example 1 except that the sphere was replaced with a crosslinked sphere consisting of (30/10/10). The thickness of this membrane was about 200 μm, and its dialysis performance was the same as in Example 1 .

Example 3 A. Preparation of poly 4-vinylpyridine microgel 10 parts of 4-vinylpyridine, 1 part of divinylbenzene, 0.2 parts of 2,2'-azobis (2-methyl-2-
Methylpropinoamidine) dihydrochloride and 5
In a 1 liter flask, 00 parts of water is polymerized at 70 ° C. for 7 hours under a nitrogen atmosphere. The obtained polymerization liquid is an emulsified liquid, and may be purified by dialysis, or may be purified by filtration under pressure, followed by washing with water and washing. The dried product can be redispersed in water or methanol. The obtained polymer spheres have a particle size of about 150 nm when dried and about 200 n in water.
m, and about 500 nm in methanol.

B. Preparation of linear sodium polysulfonate 12 parts of sodium styrenesulfonate, 4 parts of acrylamide, 0.5 part of 2,2'-azobis (2-methyl-2
-Methylpropinoamidine) dihydrochloride,
0.8 part of diallyl malonic acid, 1 part of crotonaldehyde and 100 parts of water are placed in a flask and placed under a nitrogen atmosphere.
After reacting at 0 ° C. for 10 hours, the polymer is purified by acetone-water reprecipitation method and dried at normal temperature. The obtained polymer has a molecular weight of about 44,000 (GPC), and the polymer has an amidino group at one end.

C. Preparation of core-shell type polymer 1 part of the above-mentioned linear sodium polysulfonate of B was dissolved in 10 parts of water, and 0.5 part of sodium bicarbonate was dissolved therein.
Stir for hours. One part of epibromohydrin is added thereto and reacted at 45 ° C. for 10 hours. This reaction solution is purified by a dialysis operation. When bromine in the reaction product was ionized with an alkali and quantified, the molecular weight was about 40,000 when one was attached to one end of the polymer, which almost agreed with the analysis result by GPC. This aqueous polymer solution is adjusted to a solid content of 5% by weight, and 40 parts thereof are taken and mixed with 10 parts of a 10% by weight methanol solution of the poly-4-vinylpyridine microgel shown in the above A. After reacting at room temperature for 24 hours, the mixture was filtered, washed with water and dried under reduced pressure.

Aldehyde determination and transmission electron microscopy (TE
M) From the observation, the linear polymer B exists only on the surface of the poly (4-vinylpyridine sphere), and is present at a ratio of one to ten pyridine units. In some cases, the nitrogen atom of the pyridine ring can be completely quaternized by methyl iodide or the like. The core-shell type polymer obtained in this manner was used in place of the poly (4-vinylpyridine sphere) of Example 2, and corresponded to the same equivalent of sulfonic acid as poly (4-vinylpyridine) in the core-shell. linear polysulfone is mixed with sodium in aqueous solution cast film, after the same treatment as in example 1, 200 Kg / cm put the membrane on a stainless steel porous body
Crimping was performed at a pressure of ² . The mosaic-charged membrane of the present invention thus obtained exhibited an even more excellent desalination effect by applying pressure to the aqueous solution of the salt to be dialyzed.

[0019]

According to the present invention as described above, the use of ionic polymer spheres in the preparation of a mosaic charged membrane makes the connection of the spheres in the membrane isotropic, and the electrolyte of the formed membrane is used. Dialysis is dramatically improved. Also, in the production of the membrane, it is not necessary to consider the directionality of the polymer phase because the constituent material of the membrane is a sphere. Accordingly, the present invention, for the separation of the electrolyte, mosaic charged membrane is useful for separating or desalination of non electrolytes Ru can be manufactured in a simple process.

[0020]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating filtration and separation of an electrolyte and a non-electrolyte by a mosaic charged membrane of the present invention.

FIG. 2 is a diagram illustrating the separation performance of an electrolyte and a non-electrolyte by the mosaic charged membrane obtained in Example 1.

[Explanation of symbols]

 1: electrolyte container 2: non-electrolyte container 3: membrane 4: stirrer

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B01D 71/00-71/82 510

Claims (6)

(57) [Claims] (1) at least one polymer has a diameter of 0.0
1 to 10 μm sphere (spherical) cationic
Mosaic charged membrane from limmer and anionic polymer
Production of a mosaic charged membrane characterized by mixing one ionic polymer sphere and another ionic linear polymer solution to form a cast film when producing a run. Method. 2. The method according to claim 1, wherein at least one polymer has a diameter of 0.0
1 to 10 μm sphere (spherical) cationic
Mosaic charged membrane from limmer and anionic polymer
Upon manufacturing a run, a dispersion of an ionic polymer of the scan <br/> fair heterologous were prepared respectively, the production method of the mosaic charged membrane, characterized by cast film by mixing the dispersion. 3. The method according to claim 1, wherein at least one polymer has a diameter of 0.0
1 to 10 μm sphere (spherical) cationic
Mosaic charged membrane from limmer and anionic polymer
Upon manufacturing a run, on the surface of the scan <br/> Fair one ionic polymer, other ionic core linear polymer is chemically bonded - shell type polymer cast film, A method for producing a mosaic charged membrane, wherein the core is broken. 4. The method according to claim 1, wherein at least one polymer has a diameter of 0.0
1 to 10 μm sphere (spherical) cationic
Mosaic charged membrane from limmer and anionic polymer
Filling Upon manufacturing a run, a dispersion of spheres of ionic heterologous were prepared respectively, after casting <br/> film by mixing the dispersion, one of the ionic polymers or monomers that gap And a method for producing a mosaic charged membrane, which is further polymerized in the case of a monomer. 5. The method according to claim 1, wherein at least one of the polymers has a diameter of 0.
Cationic as spheres (spheres) of 01-10 μm
Mosaic charged membrane from polymer and anionic polymer
In producing the bran, one ionic polymer sphere is immobilized on a liquid-permeable support, and then the monomer constituting the other polymer is filled into the space between the spheres to polymerize the monomer. A method for producing a mosaic charged membrane, characterized in that: 6. A mosaic charged membrane produced by the method according to any one of claims 1 to 5.