JP7020654B2 - Anion exchange membrane and its manufacturing method - Google Patents

Description

The present invention relates to an anion exchange membrane and a method for producing the anion exchange membrane, and more specifically, can be applied to CDI (Capacitive Deionization), ED (Electrodialysis), RED (Reverse Electrodialysis), water electrolysis (Water Electrolysis) and the like. Regarding the membrane and its manufacturing method.

Ion exchange membranes are used in various fields such as fuel cells, redox flow batteries, water treatment, and seawater desalination. The ion exchange membrane has a relatively simple manufacturing process, has excellent selectivity for specific ions, has a wide range of applications, and is a major cleaning technology that can reduce the amount of fossil raw materials used and reduce environmental pollution. It is attracting worldwide attention. Since the ion exchange membrane as described above can selectively separate cations and anions in the aqueous solution, it can be used from fuel cells, electrodialysis, water splitting electrodialysis for acid and base recovery, and pickling waste liquid. It is widely used in diffusion dialysis for recovering acid and metal chemical species, ultra-pure water process, etc. Recently, in developed countries, the range of application has been further expanded with the development of high-performance ion exchange membranes. ing.

Such ion exchange membranes must have high selectivity, low permeability of solvents and nonionic solutes, low resistance to diffusion of selected permeated ions, high mechanical strength and chemical resistance. I need. Such an ion exchange membrane is required to have excellent mechanical strength and durability. Methods universally used to meet such requirements include a method of adding an inorganic substance to produce a hybrid composite film, a hot press method of heat-pressing a catalyst mixture, and a method of adding a curing agent.

The hybrid composite membrane has a disadvantage that if the swelling phenomenon of the membrane continues, a gap is formed between the additive of the membrane and the polymer membrane, and the normal ion exchange ability cannot be exhibited. Further, the method of adding the curing agent also has a disadvantage that the curing agent is eluted with the passage of time. Due to the above-mentioned problems, there is still a demand for the development of an ion exchange membrane having high durability and excellent mechanical properties.

Examples of the anion exchange membrane currently commercialized include Salemion (registered trademark) AMV of Asahi Glass and Neosepta (registered trademark) AMX of Astom.

However, commercialized anion exchange membranes are vulnerable to organic matter-induced membrane contamination and inorganic scaling, especially for organic membrane contamination, where low-mobility membrane contaminants pass through the anion exchange membrane. Will be caused by. To solve this, there is a method of reducing the degree of cross-linking so that the permeability of an organic substance having a relatively large molecular weight can be increased, but in this case, the mechanical strength and chemical stability of the membrane are lowered. There's a problem.

Further, in the case of a commercialized anion exchange membrane, although it is excellent in ion exchange capacity and electrical properties, it has problems that it is expensive and has low durability.

The present invention is for solving the above-mentioned problems of the prior art, and an object of the present invention is to be able to uniformly realize the mechanical properties and the ion exchange ability while being excellent. It is an object of the present invention to solve the problem that the production cost increases due to the elution and disposal of alkoxyvinylsilane, and to provide an economical anion exchange membrane and a method for producing the same.

One aspect of the invention is a continuous phase matrix comprising a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 and a porous support comprising a discontinuous phase silane-modified polyolefin crosslinked in the matrix; and said. Provided is an anion exchange membrane containing an anion conductive substance impregnated in the pores of a porous support or applied to the surface of the porous support.

In one example, the content of the silane-modified polyolefin in the porous support can be 0.1-5% by weight.

In one embodiment, the silane can be vinylsilane containing an alkoxy group.

In one embodiment, the anionic conductive material can be an aminated polymer.

In one example, the aminated polymer can have the structure of the following chemical formula (Chemical formula 1).

In the above formula, Y is a covalent bond (-), -CO-, -SO _2- or -O-, and Z and D are covalent bonds (-), -O-, or -S-, respectively. C is a covalent bond (-), -C (CH ₃ ) ₂ -or-C (CF ₃ ) _2- , and R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ R ₂ , R ₃ , and R ₄ are -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or-(, respectively. CH ₂ ) ₃ NH (CH ₃ ) Cl, x and y are arbitrary repeating units, respectively, and x / (x + y) is 0.001 to 1.

In one example, the amineted polymer is an attended PAES (polyphenylene sulfide), an aminated PEK (polyester ketone), an aminated PEEK (polyphenylene sulfide), an aminated PS (polysulfone), aminated PS (polysulfone). It may be one selected from the group consisting of polyphenylene sulfide), aminolated PPS (polyphenylene sulfide) and a combination of two or more of these.

In one embodiment, the porous support may further contain an inorganic filler, and the content of the inorganic filler in the porous support may be 10 to 70% by weight.

Another aspect of the present invention is (a) a step of processing a composition containing a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 and a silane-modified polyolefin to produce a porous support; (b). ) A step of cross-linking the silane-modified polyolefin contained in the porous support; and (c) a step of impregnating the porous support with a solution containing an anionic conductive substance and a solvent; Provide a manufacturing method.

In one embodiment, prior to step (c), the porous support is plasma treated in the presence of brom gas and a bimolecular nucleophilic substitution reaction ( _SN 2 reaction) with an amine group-containing compound. The step of causing; can be further included.

In one embodiment, the plasma treatment can be performed for 0.5-90 minutes.

The anion exchange membrane and the method for producing the anion exchange membrane according to one aspect of the present invention use the polyolefin in which the silane modification has been completed without separately performing the silane modification reaction of the polyolefin in the production of the support of the anion exchange membrane, and the method thereof is used. By mixing and using a polyolefin having a weight average molecular weight in a certain range in a certain ratio, it can be uniformly realized while having excellent mechanical properties, and the manufacturing cost is due to the elution and disposal of alkoxyvinylsilane. It is possible to solve the problem of rising and maximize productivity and economic efficiency.

According to another aspect of the present invention, the support of the anion exchange membrane is subjected to plasma treatment of the porous support in the presence of brom gas, and a bimolecular nucleophilic substitution reaction with a compound containing an amine group ( By subjecting the support to the surface of the support and the surface of the internal pores by subjecting it to the S _N 2 reaction), the binding force to the anion conductive substance impregnated in the support and the durability of the anion exchange film due to the binding force. And ionic conductivity can be improved.

The effects of the present invention are not limited to the above-mentioned effects, but should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

FIG. 1 is a cross-sectional SEM image of a porous support according to an embodiment of the present invention (Production Example 1-1). FIG. 2 is a cross-sectional SEM image of an anion exchange membrane according to a comparative example (Comparative Example 1) of the present invention. FIG. 3 is a cross-sectional SEM image of an anion exchange membrane according to an embodiment of the present invention (Example 1). FIG. 4 is a cross-sectional SEM image of a porous support according to an embodiment of the present invention (Production Example 1-9).

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the invention can be embodied in a variety of different forms and is therefore not limited to the examples described herein. In addition, in order to clearly explain the present invention in the drawings, parts unrelated to the description are omitted, and similar parts are designated by reference numerals in the specification as a whole.

In the general specification, when an arbitrary part is "connected" to another part, this is not only when it is "directly connected", but also when another member is sandwiched between them. Including the case of "indirectly connected".

Also, when any part "contains" a component, it does not exclude other components, but may further include other components, unless otherwise stated. means.

Anion Exchange Membrane One aspect of the present invention is a porous support comprising a continuous phase matrix containing a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 and a discontinuous phase silane-modified polyolefin crosslinked in the matrix. Provided is an anion exchange membrane containing a body; and an anionic conductive substance impregnated in the pores of the porous support or applied to the surface thereof.

The support may be a kind of porous membrane having pores formed inside. The anion conductive substance may be impregnated in at least a part of the pores inside the support, and may be further coated on at least a part of the surface of the support. The anion conductive substance inside the pores and the anion conductive substance on the surface of the support may be interconnected.

In the support, the silane-modified polyolefin is crosslinked in the matrix to firmly support and fix the matrix, whereby the mechanical properties of the support can be improved. As used herein, the term "matrix" means a component that constitutes a continuous phase in a support containing two or more components. That is, in the support, a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 exists in a continuous phase, and a silane-modified polyolefin crosslinked therein can exist in a discontinuous phase.

In order to substantially utilize the anion exchange membrane of the present invention, it is necessary to uniformly adjust the distribution of the silane-modified polyolefin so that the crosslinked silane-modified polyolefin is uniformly distributed in the support. There is. When the cross-linking reaction of the silane-modified polyolefin is biased to a part of the support, the required level of mechanical properties cannot be realized, and in particular, the mechanical properties due to the region of the support. The deviation of the product may increase, and the reliability and reproducibility of the product may be significantly reduced.

According to one embodiment of the present invention, the silane-modified polyolefin is used in the process of kneading the polyolefin and the silane-modified polyolefin in an extruder by adjusting the molecular weight of the polyolefin constituting the matrix to a certain range. It can be uniformly dispersed in the polyolefin. The weight average molecular weight M _w of the polyolefin can be 250,000-450,000. If the weight average molecular weight of the polyolefin exceeds 450,000, the viscosity may increase and the processability may decrease, and if it is less than 250,000, the viscosity becomes excessively low and the silane-modified polyolefin is dispersed. The properties are extremely reduced, and in some cases, phase separation or layer separation may occur between the polyolefin and the silane-modified polyolefin.

The polyolefin may be one selected from the group consisting of polyethylene, polypropylene, ethylene vinyl acetate, ethylene butyl acrylate, ethylene ethyl acrylate and a combination of two or more thereof or a copolymer thereof, and polyethylene is preferable. There may be, but it is not limited to this.

The content of the silane-modified polyolefin in the support can be 0.1 to 5% by weight. If the content of the silane-modified polyolefin in the support is less than 0.1% by weight, the required level of mechanical properties cannot be realized, and if it exceeds 5% by weight, the mechanical properties are required. It is disadvantageous in terms of economic efficiency and productivity because it is converged to a high level.

The silane can be vinylsilane containing an alkoxy group. For example, the vinylsilane containing an alkoxy group may be one selected from the group consisting of trimethoxyvinylsilane, triethoxyvinylsilane, triacetoxyvinylsilane, and a combination of two or more thereof, and is preferably trimethoxyvinylsilane. However, it is not limited to this.

The support may further contain an inorganic filler. The inorganic fillers include silica (SiO ₂ ), titanium dioxide (TIO ₂ ), alumina (Al ₂ O ₃ ), zeolite (zeolite), AlOOH, barium titanate (BaTIO ₂ ), talc (Talk), and aluminum hydroxide (Al). It may be one selected from the group consisting of (OH) ₃ ), calcium carbonate (CaCO ₃ ) and a combination of two or more thereof, and preferably has an average particle size of 10 to 1,000 nm or 10 to 600 nm. It may be spherical nanoparticles having a surface, preferably nanoparticles whose surface has been hydrophobized or hydrophilized. The content of the inorganic filler in the support may be 10 to 70% by weight, preferably 10 to 60% by weight. If the content of the inorganic filler is less than 10% by weight, the mechanical strength, acid resistance, chemical resistance, and flame retardancy of the support may decrease, and if it exceeds 70% by weight, the support may be deteriorated. Flexibility and workability may decrease.

For example, silica (SiO ₂ ) may have a hydrocarbon layer formed of hydrophobic linear hydrocarbon molecules formed on its surface. Since silica itself has hydrophilic properties, linear hydrocarbon molecules, such as spherical silica nanoparticles coated with (poly) ethylene, are preferred in order to improve compatibility with hydrophobic polyethylene.

As described above, the support having a structure in which a certain amount of silane-modified polyolefin is crosslinked in a polyolefin-based matrix whose molecular weight is adjusted to a certain range meets one or more of the following conditions (i) to (ix). Can be met. (I) Air permeability 50 to 300 sec / 100 ml, preferably 125 to 300 sec / 100 ml; (ii) Drilling strength 15 to 65 gf / μm, preferably 21.5 to 65 gf / μm; (iii) Longitudinal (MD) tensile strength 500 to 3,000 kgf / cm ² , preferably 700 to 2,000 kgf / cm ² ; (iv) lateral (TD) tensile strength 500 to 2,500 kgf / cm ² , preferably 700 to 2,000 kgf / cm ² ; (V) Longitudinal (MD) tensile elongation 40% or more, preferably 40-80%; (vi) Lateral (TD) tensile elongation 40% or more, preferably 40-55%; (vii) at 120 ° C. Longitudinal (MD) heat shrinkage 20% or less, preferably 10% or less; (viii) horizontal (TD) heat shrinkage 20% or less, preferably 15% or less at 120 ° C.; (ix) meltdown temperature 170- 250 ° C, preferably 200 to 250 ° C, more preferably 225 to 250 ° C.

The support can be hydrophilized and sulfonated to satisfy excellent ionic conductivity. The average pore size of the hydrophilized support can be 20-2,000 nm, the contact angle with moisture (H ₂ O) can be 15 ° or less, and a negative value (-) on the surface of the porous membrane. ), The absolute value of the zeta potential may be 10 mV or more, preferably 15 mV or more, and more preferably 20 mV or more. The porosity of the support can be 30-90%, preferably 50-80%.

The hydrophilized support has a high affinity with the anionic conductive material, which is essentially hydrophilic, because the -SO ₃ groups generated on the surface and the surface of the internal pores are hydrophilic. ) Can be easily bound to the anion-conducting substance, and the binding force thereof can be strengthened, so that the durability of the anion-exchanged membrane can be significantly improved, and the support and the anion-conducting substance can be used. Since the disappearance of the contained hydrophilic groups is minimized, the ionic conductivity can also be improved.

The anionic conductive substance can be an amineized polymer (or an aminated polymer), and preferably the degree of amineation of the aminized polymer can be 40 to 70%. As used herein, the term "degree of amination" refers to the total number of moles of a plurality of monomers forming the aminated polymer, which is one of the aminated polymers. When the number of moles of the above-mentioned monomer substituted with an amine group is n, it can be calculated by the formula n / m. For example, if n / m is 1, the degree of amineation can be 100%.

In general, the higher the degree of amination of an anionic conductive substance, especially the anionic conductive polymer, the higher the ionic conductivity of the polymer, but the higher the hydrophilicity, and the more soluble it is in water. The phenomenon of severe swelling occurs. On the other hand, when the degree of amination is low, the hydrophobicity is strong and the water resistance and durability are improved, but there is a problem that the ionic conductivity is lowered. Therefore, by adjusting the degree of amineation of the anionic conductive substance in the range of 40 to 70%, ion conductivity, water resistance, and durability can be realized in an equilibrium.

The amineized polymer can have the structure of the following chemical formula (Chemical formula 2).

In the above formula, Y is a covalent bond (-), -CO-, -SO _2- or -O-, and Z and D are covalent bonds (-), -O- or -S-, respectively. C is a covalent bond (-), -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , and R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ , R ₂ , R ₃ , R ₄ are -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or- (CH ₂ ) ₃ , respectively. It is NH (CH ₃ ) Cl, x and y are arbitrary repeating units, respectively, and x / (x + y) is 0.001 to 1.

For example, the aminated polymer may be identified as PAES (polysulfone sulfide), aminated PEK (polyether ketone), aminated PEEK (polyphenylene sulfide), aminated PS (polysulfone), or , Aminated PPS (polyphenylene sulfide) and one selected from the group consisting of two or more combinations thereof, but is not limited thereto.

Method for Producing Anion Exchange Membrane Another aspect of the present invention is to process a composition containing (a) a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 and a silane-modified polyolefin to support porosity. The step of producing the body; (b) the step of cross-linking the silane-modified polyolefin contained in the porous support; and (c) the step of impregnating the porous support with a solution containing an anionic conductive substance and a solvent. A method for producing an anion exchange membrane containing; is provided.

In the step (a), the composition containing the polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 and the silane-modified polyolefin is thrown into an extruder, then extruded and discharged via a T-die. A porous support can be produced by forming into a sheet form and then stretching the product.

The polyolefin may be one selected from the group consisting of polyethylene, polypropylene, ethylene vinyl acetate, ethylene butyl acrylate, ethylene ethyl acrylate and a combination of two or more thereof or a copolymer thereof, and polyethylene is preferable. There may be, but it is not limited to this.

The composition may contain 20-40 parts by weight of the polyolefin and 0.1-10 parts by weight of the silane-modified polyolefin. If the content of the silane-modified polyolefin in the composition is less than 0.1 parts by weight, the required level of mechanical properties cannot be realized, and if it exceeds 10 parts by weight, the mechanical properties are required. It is disadvantageous in terms of economic efficiency and productivity because it converges to a high level.

The silane can be vinylsilane containing an alkoxy group. For example, the vinylsilane containing an alkoxy group may be one selected from the group consisting of trimethoxyvinylsilane, triethoxyvinylsilane, triacetoxyvinylsilane, and a combination of two or more thereof, and is preferably trimethoxyvinylsilane. However, it is not limited to this.

The composition may further contain 60-80 parts by weight of the pore-forming agent. The pore-forming agent can play a role of forming pores by being extracted and removed inside the support by a wet method utilizing Thermally Induced Phase Separation.

In the wet method, the support containing the pore-forming agent may be immersed in an extraction tank on which a solvent is supported. The extraction temperature may be 15 to 80 ° C., preferably 25 to 40 ° C., and the extraction time may be 0.1 to 60 minutes, preferably 1 to 20 minutes.

Examples of the pore-forming agent include paraffin oil, paraffin wax, mineral oil, solid paraffin, soybean oil, oil vegetable oil, palm oil, palm oil, di-2-ethylhexyl phthalate, dibutyl phthalate, diisononyl phthalate, diisodecyl phthalate, and bis (2). -Propylheptyl) It may be one selected from the group consisting of phthalate, naphthenic oil and a combination of two or more thereof, preferably paraffin oil, and more preferably the kinematic viscosity at 40 ° C. It may be, but is not limited to, paraffin oil of 50 to 100 cSt.

The solvent for extracting the pore-forming agent may be one selected from the group consisting of pentane, hexane, benzene, dichloromethane, carbon tetrachloride, methyl ethyl ketone, acetone and a combination of two or more thereof. Dichloromethane may be preferable, but the present invention is not limited thereto.

The composition may further include a cross-linking catalyst. When the composition further contains a cross-linking catalyst, the cross-linking reaction in the step (b) can be promoted. As such a cross-linking catalyst, generally, carboxylates of metals such as tin, zinc, iron, lead and cobalt, organic bases, inorganic acids and organic acids can be used. For example, the cross-linking catalyst may be dibutyltin dilaurate, dibutyltin diacetate, stannous acetate, stannous caprylate, zinc naphthenate, zinc caprylate, cobalt naphthenate, ethylamine, dibutylamine, hexylamine, pyridine, sulfuric acid, hydrochloric acid. Inorganic acids such as, toluene sulfonic acid, acetic acid, stearic acid, and organic acids such as maleic acid may be used, and dibutyltin dilaurate may be preferable, but the present invention is not limited thereto.

Conventionally, the cross-linking catalyst has been used by a method such as adding it at the time of producing a silane-modified polyolefin or applying a solution or dispersion of the cross-linking catalyst to a support. However, in such a conventional method, it is difficult to uniformly disperse the cross-linking catalyst together with the silane-modified polyolefin. As described above, the silane-modified polyolefin contained in the support needs to be uniformly dispersed before crosslinking, and at this time, the crosslinking catalyst involved in the crosslinking reaction of the silane-modified polyolefin also needs to be uniformly dispersed. There is.

On the other hand, by premixing the cross-linking catalyst with the pore-forming agent and charging the cross-linking catalyst through the side feeder of the extruder, the cross-linking catalyst is uniformly dispersed together with the silane-modified polyolefin to improve the efficiency of the cross-linking reaction. Can be enhanced.

The content of the cross-linking catalyst in the composition can be 0.01-5% by weight. If the content of the cross-linking catalyst is less than 0.01% by weight, the cross-linking reaction cannot be promoted to the required level, and if it exceeds 5% by weight, the reaction rate is converged to the required level. It is disadvantageous in terms of economy and productivity.

The stretching performed in the step (a) can be performed by a known method such as uniaxial stretching or biaxial stretching (sequential or simultaneous biaxial stretching). In the case of sequential biaxial stretching, the stretching ratio may be 4 to 20 times in the horizontal direction (MD) and the vertical direction (TD), respectively, and the surface magnification thereof may be 16 to 400 times.

In the step (b), the silane-modified polyolefin contained in the porous support can be crosslinked. The cross-linking can be performed by locating the porous support in a constant temperature and humidity chamber in which the temperature and humidity are controlled to a certain range, in which the step (b) is mutual with the step (a). Since it is carried out in a moisture environment where it is difficult to raise the temperature above a certain level even if it is discontinuous or continuous, the cross-linking reaction can take an excessive time. On the other hand, in the step (b), the porous membrane was put into a cross-linking tank carrying a solution having a boiling point exceeding 100 ° C., preferably 120 ° C. or higher, more preferably 150 ° C. or higher, and continuously passed through. By doing so, the time required for the crosslinking reaction can be significantly shortened and the productivity can be improved.

Specifically, since the solution contains a component having a boiling point exceeding 100 ° C., the temperature condition may be exceeded 100 ° C., preferably 120 ° C. or higher at the time of the crosslinking reaction to promote the crosslinking reaction. As the component, one selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol and a combination of two or more thereof can be used. Since such a component has hygroscopicity, a cross-linking reaction can be caused by the water contained in the component, but if necessary, a certain amount of water can be mixed and used.

In addition, the solution can further contain a cross-linking catalyst, in which case the cross-linking reaction can be sufficiently promoted without mixing a certain amount of water. The content of the cross-linking catalyst in the solution can be 0.5 to 15% by weight. If the content of the cross-linking catalyst is less than 0.5% by weight, the cross-linking reaction cannot be promoted to the required level, and if it exceeds 15% by weight, the reaction rate is converged to the required level. It is disadvantageous in terms of economy and productivity.

The cross-linking catalyst contained in the solution supported on the cross-linking tank has an action and effect essentially similar to those contained in the composition. However, the cross-linking catalyst contained in the composition, that is, the cross-linking catalyst charged through the side feeder of the extruder in the step (a), is the central portion (center) of the porous support in the step (b). While the silane-modified polyolefin distributed in the layer) can be effectively crosslinked, it is difficult to actively participate in the cross-linking reaction of the silane-modified polyolefin distributed in the surface portion (skin layer). The cross-linking catalyst contained in the solution supported on the cross-linking tank comes into contact with the surface portion (skin layer) of the porous support when the porous support passes through the cross-linking tank, so that the porous support is porous. The cross-linking reaction of the silane-modified polyolefin distributed on the surface portion (skin layer) of the support can be further promoted. The types and effects of the cross-linking catalyst are as described above.

Prior to step (c), the porous support is plasma treated in the presence of brom gas and subjected to a bimolecular nucleophilic substitution reaction ( _SN 2 reaction) with a compound containing an amine group; Can include.

Through the plasma treatment and the bimolecular nucleophilic substitution reaction, the surface of the porous support and the surface of the internal pores are made hydrophilic at the time of production into the anion exchange membrane described later, that is, the surface and the internal pores of the porous support are hydrolyzed. The surface can be positively charged to improve the binding force to the anion conductive material, thereby significantly improving the durability of the anion exchange membrane, especially long-term durability and ion conductivity. be able to.

Conventionally, in order to make the surface of a porous support hydrophilic and to realize a certain level of ionic conductivity, a wet process in which the porous support is immersed in a reaction solution or the like for a certain period of time to be sulfonated has been performed. Although it was mainly used, in this case, the wet process is performed separately from the plasma treatment, such as before or after the plasma treatment, and the process is complicated, and there is a problem that a large amount of process waste liquid is generated.

On the other hand, since the process gas used during the plasma treatment contains brom gas, a single dry step (plasma treatment) of the plasma treatment is performed without a wet step such as immersing the porous support in a reaction solution or the like. Through dry plasma), brom functional groups are generated on the surface of the porous support and the surface of the internal pores, that is, bromization and bimolecular nucleophilic substitution reaction are carried out to carry out the hydrophilicity and ionic conductivity of the porous support. Can be maximized, the conventional complicated process can be simplified, and it is also advantageous in terms of the environment.

The plasma treatment can be carried out for 0.5 to 90 minutes, preferably 0.5 to 20 minutes. If the plasma treatment is performed in less than 0.5 minutes, the porous support cannot be hydrophilized and brominated to the required level, and if it is performed in more than 90 minutes, the degree of hydrophilization and bromification cannot be achieved. Since the degree is converged to a certain level, the process efficiency may decrease.

After the plasma treatment, the porous support is subjected to a bimolecular nucleophilic substitution reaction ( _SN ) with a compound containing an amine group, for example, 1- (2-aminoethyl) Piperazine. By performing 2 reactions), the surface of the porous support and the surface of the internal pores can be positively charged to improve the binding force with the anion conductive substance, thereby exchanging anions. The durability of the membrane, in particular the long-term durability and ionic conductivity, can be significantly improved.

In the step (c), the porous support is impregnated and / or coated with a solution containing an anionic conductive substance and a solvent, and the pores of the porous support are filled with the anionic conductive substance. The anion conductive substance can be coated on the surface of the porous support with a certain thickness, if necessary. The thickness of the anion exchange membrane filled and / or coated with the anion conductive substance by the step (c) can be 30 to 200 μm.

The impregnation and / or coating is a method of (i) impregnating the hydrophilized porous support into an impregnation tank filled with the solution for a certain period of time, and (ii) the hydrophilized porous support. It may be performed by a coating device for transmitting a solution, for example, a method of coating with a roll coater, a bar coater, or a method in which the above (i) and (ii) are combined.

In particular, when the step (c) is performed by a method using a roll coater among the (ii), the roll coater is a first roll that transfers the solution to one surface of the hydrophilic porous support. And while supporting and transferring the porous support in contact with the other surface of the hydrophilic support, an inhalation means having a predetermined structure and form is mounted inside the first roll. It can include a second roll that allows the transferred solution to fill the pores of the porous support smoothly, without any open space. Further, the solution transmitted in excess of the amount required for the coat is sucked by the suction means mounted inside the second roll and then transferred to the means for supplying the solution to the first roll. The solution can be reused.

The content of the anionic conductive substance in the solution can be 10 to 60% by weight. If the content of the anion conductive substance is less than 10% by weight, the ion conductivity of the ion exchange membrane may decrease, and if it exceeds 60% by weight, the ion conductivity does not improve any more, so that it is unnecessary. It is disadvantageous in terms of economic efficiency because it consumes a lot of raw materials.

The anionic conductive material can be an aminated polymer. The types and effects of the amineized polymer are as described above.

The solvent of the solution is a group consisting of ester-based, ether-based, alcohol-based, ketone-based, amide-based, sulfone-based, carbonate-based, aliphatic hydrocarbon-based, aromatic hydrocarbon-based, and a combination of two or more thereof. It may be one selected from the above, preferably an amide-based solvent, and more preferably N-methyl-2-pyrrolidone.

Examples of the ester solvent include methyl acetate, ethyl acetate, n-butyl acetate, cellosolve acetate, propylene glycol monomethyl acetate, 3-methoxybutyl acetate, methyl butyl rate, ethyl butyl rate, propyl propionate and the like. It is not limited to this.

Examples of the ether-based solvent include diethyl ether, dipropyl ether, dibutyl ether, butyl ethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, octyl ether, and hexyl ether. It is not limited to this.

Examples of the alcohol-based solvent include, but are not limited to, methanol, ethanol, propanol, isopropanol, n-butanol, amyl alcohol, cyclohesisanol, octyl alcohol, and decanol.

Examples of the ketone solvent include, but are not limited to, acetone, cyclohexanone, methylamylketone, diisobutylketone, methylethylketone, and methylisobutylketone.

Examples of the amide-based solvent include, but are not limited to, N-methyl-2-pyrrolidone, 2-pyrrolidone, N-methylformamide, dimethylformamide, and dimethylacetamide.

Examples of the sulfone solvent include, but are not limited to, ditimel sulfoxide, diethyl sulfoxide, diethyl sulfone, tetramethylene sulfone and the like.

Examples of the carbonate-based solvent include, but are not limited to, ethylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, propylene carbonate, ethylene carbonate, and dibutyl carbonate.

Examples of the aliphatic hydrocarbon solvent include pentane, hexane, heptane, octane, nonane, decane, dodecane, tetradecane, hexadecane and the like, and examples of the aromatic hydrocarbon solvent include benzene, ethylbenzene, chlorobenzene and toluene. Examples include, but are not limited to, xylene.

Hereinafter, embodiments of the present invention will be described in detail. As the silane-modified polyethylene of the examples, SH-100X of TSC and XHE740N of MCPP were used respectively or in combination, and as the silane-modified polyethylene of the comparative example, Linkron HF-700N of Mitsubishi Chemical was used. ..

Production Example 1-1
At 25 parts by weight of high density polyethylene (HDPE) with a weight average molecular weight M _w of 350,000 and a molecular weight distribution M _w / M _n of 5, 0.5 parts by weight of silane-modified polyethylene, and 40 ° C. 74.5 parts by weight of paraffin oil having a kinematic viscosity of 70 cSt was mixed and charged into a twin-screw extruder (inner diameter 58 mm, L / D = 56, Twin screw extruder). The mixture was discharged from the twin-screw extruder under the conditions of 200 ° C. and a screw rotation speed of 40 rpm with a T-die having a width of 300 mm. After that, a base sheet having a thickness of 800 μm was manufactured by passing it through a casting roll having a temperature of 40 ° C. The base sheet was stretched 6 times in the longitudinal direction (MD) with a roll stretcher at 110 ° C. and 7 times in the transverse direction (TD) with a tenter stretching machine at 125 ° C. to produce a stretched film. The stretched film was impregnated in a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 1 minute to produce a porous film. The porous membrane was dried under the condition of 50 ° C. After that, the porous film was heated to 125 ° C. with a tenter stretching machine, then stretched 1.45 times in the lateral direction (TD) and then relaxed, and heat-fixed so as to be 1.25 times that before stretching. .. The porous membrane was crosslinked in a constant temperature and humidity chamber at 85 ° C. and a humidity of 85% for 72 hours to produce a porous support.

Production Example 1-2
29.5 parts by weight of high-density polyethylene having a weight average molecular weight M _w of 350,000 and a molecular weight distribution M _w / M _n of 5, 0.5 parts by weight of silane-modified high-density polyethylene, and kinematic viscosity at 40 ° C. 70 parts by weight of paraffin oil having a viscosity of 70 cSt was mixed and charged into a twin-screw extruder (inner diameter 58 mm, L / D = 56). The side of the twin-screw extruder so that the cross-linking catalyst dibutyltin dilaurate is pre-dispersed in a part of the paraffin oil and becomes 0.5% by weight based on the total weight of the mixture passing through the twin-screw extruder. It was thrown in via an injector. The mixture was discharged from the twin-screw extruder with a T-die having a width of 300 mm under the conditions of 200 ° C. and a screw rotation speed of 40 rpm. After that, a base sheet having a thickness of 800 μm was manufactured by passing it through a cast roll having a temperature of 40 ° C. The base sheet was stretched 6 times in the longitudinal direction (MD) with a roll stretching machine at 110 ° C. and 7 times in the transverse direction (TD) with a tenter stretching machine at 125 ° C. to produce a stretched film. The stretched film was impregnated in a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 1 minute to produce a porous film. The porous membrane was dried under the condition of 50 ° C. for 5 minutes. After that, the porous membrane was heated to 125 ° C. with a tenter stretching machine, stretched 1.45 times in the lateral direction (TD), and then relaxed 1.25 times. The porous membrane was crosslinked in a constant temperature and humidity chamber at 85 ° C. and a humidity of 85% for 72 hours to produce a porous support.

Production Example 1-3
High-density polyethylene having a weight average molecular weight M _w of 350,000 and a molecular weight distribution M _w / M _n of 5 has a weight average molecular weight M _w of 250,000 and a molecular weight distribution M _w / M _n of 6. A porous support was produced by the same method as in Production Example 1-1, except that it was changed to high-density polyethylene.

Production Example 1-4
High-density polyethylene having a weight average molecular weight M _w of 350,000 and a molecular weight distribution M _w / M _n of 5 has a weight average molecular weight M _w of 250,000 and a molecular weight distribution M _w / M _n of 6. A porous support was produced by the same method as in Production Example 1-2, except that it was changed to high-density polyethylene.

Production Example 1-5
Production Example 1-1, except that the stretched film was not crosslinked in a constant temperature and humidity chamber, but propylene glycol was placed in a crosslinking tank heated to 160 ° C. and continuously passed for 30 minutes for crosslinking. The porous support was manufactured by the same method as above.

Production Example 1-6
A solution of propylene glycol and dibutyltin dilaurate mixed at a weight ratio of 95: 5 was placed in a cross-linking tank heated to 160 ° C. without cross-linking the stretched film in a constant temperature and humidity bath, and passed continuously for 10 minutes. A porous support was produced by the same method as in Production Example 1-1, except that the porous support was cross-linked.

Production Example 1-7
Production Example 1-1, except that the stretched film was put into a cross-linking tank heated to 120 ° C. without being cross-linked in a constant temperature and humidity bath, and passed continuously for 60 minutes for cross-linking. The porous support was manufactured by the same method as above.

Production Example 1-8
A solution of ethylene glycol and dibutyltin dilaurate mixed at a weight ratio of 90:10 was placed in a cross-linking tank heated to 120 ° C. without cross-linking the stretched film in a constant temperature and humidity bath, and passed continuously for 15 minutes. A porous support was produced by the same method as in Production Example 1-1, except that the porous support was subjected to cross-linking.

Production Example 1-9
20 parts by weight of nanosilica particles having an average particle size of 600 nm coated with ethylene, 29.5 parts by weight of high-density polyethylene having a weight average molecular weight _Mw of 350,000, MFR 0.8 g / 10 min, density 0.958 g / 0.5 parts by weight of trimethoxyvinylsilane-modified high-density polyethylene (ml) and 70 parts by weight of paraffin oil having a kinematic viscosity at 40 ° C. were mixed, and nanosilica particles were dispersed using a high-speed mixer.

After that, after removing the fine bubbles generated in the mixing process through the vacuum defoaming step, the particles were put into a twin-screw extruder (inner diameter 58 mm, L / D = 56). After discharging with a T-die having a width of 300 mm with the twin-screw extruder under the conditions of 200 ° C. and a screw rotation speed of 40 rpm, a base sheet having a thickness of 800 μm was manufactured by passing through a cast roll having a temperature of 40 ° C. At this time, the input content was controlled so that the content of nanosilica in the base sheet was 51.4% by weight. The base sheet was stretched 6 times in the longitudinal direction (MD) with a roll stretching machine at 110 ° C. and 7 times in the transverse direction (TD) with a tenter stretching machine at 125 ° C. to produce a stretched film. The stretched film was impregnated into a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 1 minute. The film from which the paraffin oil had been removed was dried at 50 ° C. for 5 minutes. After that, it was heated to 125 ° C. with a tenter stretching machine, stretched 1.45 times in the lateral direction (TD), and then relaxed 1.25 times. The film was crosslinked in a constant temperature and humidity chamber at 85 ° C. and 85% humidity for 72 hours to produce a porous support.

Production Example 1-10
28.5 parts by weight of high-density polyethylene having a weight average molecular weight M _w of 350,000 and a molecular weight distribution M _w / M _n of 5, 1.5 parts by weight of silane-modified polyethylene, and 70 cSt kinematic viscosity at 40 ° C. 70 parts by weight of paraffin oil was mixed and charged into a twin-screw extruder (inner diameter 58 mm, L / D = 56). The mixture was discharged from the twin-screw extruder under the conditions of 210 ° C. and a screw rotation speed of 45 rpm with a T-die having a width of 300 mm. After that, a base sheet having a thickness of 800 μm was manufactured by passing it through a cast roll having a temperature of 40 ° C. The base sheet was stretched 6 times in the longitudinal direction (MD) with a roll stretching machine at 110 ° C. and 7 times in the transverse direction (TD) with a tenter stretching machine at 125 ° C. to produce a stretched film. The stretched film was impregnated in a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 1 minute to produce a porous film. The porous membrane was dried under the condition of 50 ° C. After that, the porous film was heated to 125 ° C. with a tenter stretching machine, then stretched 1.45 times in the lateral direction (TD) and then relaxed, and heat-fixed so as to be 1.25 times that before stretching. .. The porous membrane was crosslinked in a constant temperature and humidity chamber at 85 ° C. and a humidity of 85% for 72 hours to produce a porous support.

Comparative Manufacturing Example 1-1
A twin-screw extruder (inner diameter 58 mm, inner diameter 58 mm,) was mixed with 45 parts by weight of silane-modified polyethylene having an MFR of 0.8 g / 10 min and a density of 0.958 g / cm ³ and 55 parts by weight of paraffin oil having a kinematic viscosity of 70 cSt at 40 ° C. It was put into L / D = 56). After discharging with a T-die having a width of 300 mm with the twin-screw extruder under the conditions of 160 ° C. and a screw rotation speed of 40 rpm, a base sheet having a thickness of 60 μm was manufactured by passing through a cast roll having a temperature of 40 ° C. A crosslinked film was produced by applying a dibutyltin dilaurate aqueous dispersion having a concentration of 30% by weight on both surfaces of the base sheet and then proceeding with a silane crosslinking reaction in warm water having a temperature of 85 ° C. for 1 hour. The crosslinked film was impregnated into a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 30 minutes. The crosslinked film was dried in an oven at a temperature of 80 ° C. for 30 minutes to produce a porous support.

Comparative Production Example 1-2
35 parts by weight of high-density polyethylene having a melting temperature of 135 ° C. and a weight average molecular weight of 300,000, 65 parts by weight of paraffin oil having a kinematic viscosity of 40 cSt at 40 ° C., 2 parts by weight of trimethoxyvinylsilane, 2 parts by weight of dibutyltin dilaurate. 2 parts by weight and 2 parts by weight of 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane (2,5-dimethyl-2,5-di (tert-butylperoxy) hexane) are mixed and biaxial. It was put into an extruder (inner diameter 58 mm, L / D = 56). A silane-modified polyolefin composition was produced by reaction-extruding with the twin-screw extruder under the conditions of 200 ° C. and a screw rotation speed of 30 rpm. A base sheet having a thickness of 800 μm was manufactured. The base sheet was stretched 5.5 times in the longitudinal direction (MD) with a roll stretching machine at 108 ° C. and 5.5 times in the transverse direction (TD) with a tenter stretching machine at 123 ° C. to produce a stretched film. The stretched film was impregnated into a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 10 minutes. The film from which the paraffin oil was removed was heat-fixed at 127 ° C. to produce a porous support. The porous support was crosslinked in a constant temperature and humidity chamber at 80 ° C. and 90% humidity for 24 hours to produce a porous support.

Comparative manufacturing example 1-3
5 parts by weight of high-density polyethylene having a weight average molecular weight of 500,000, 10 parts by weight of silane-modified polyethylene having an MFR of 0.5 g / 10 min and a density of 0.942 g / ml, and an kinematic viscosity at 40 ° C. of 60 cSt. 85 parts by weight of paraffin oil was mixed and charged into a twin-screw extruder (inner diameter 58 mm, L / D = 56). After discharging with a T-die having a width of 300 mm with the twin-screw extruder under the conditions of 160 ° C. and a screw rotation speed of 40 rpm, the mixture is passed through a cast roll having a temperature of 40 ° C. and rolled at 115 ° C. to have a thickness of 500 μm. Manufactured the base sheet of. When some defects occurred in the manufacturing process of the base sheet, they were discarded and a base sheet having a normal appearance was selected and used.

The base sheet was stretched 3.5 times in the longitudinal direction (MD) with a roll stretching machine at 115 ° C. and 3.5 times in the transverse direction (TD) with a tenter stretching machine at 115 ° C. to produce a stretched film. The stretched film was impregnated into a dichloromethane leaching tank at 25 ° C., and paraffin oil was extracted and removed for 1 minute. The film from which the paraffin oil had been removed was dried at 50 ° C. for 5 minutes, and the film was crosslinked in a constant temperature and humidity chamber at 90 ° C. and 95% humidity for 24 hours. After that, it was heat-treated at 110 ° C. for 30 minutes to produce a porous support.

Comparative Production Example 1-4
The same method as in Production Example 1-1 was used except that the stretched film was put into a cross-linking tank on which boiling water was supported and continuously passed through the cross-linking without cross-linking in a constant temperature and humidity bath. A porous support was manufactured.

Comparative Production Example 1-5
Production Example 1-1, except that the stretched film was put into a cross-linking tank on which warm water heated to 80 ° C. was supported without being cross-linked in a constant-temperature and constant-humidity tank, and was continuously passed through and cross-linked. The porous support was manufactured by the same method as above.

Experimental Example 1
The test method for each of the physical properties measured in the present invention is as follows. Unless otherwise stated for temperature, measurements were taken at room temperature (25 ° C.).

-Thickness (μm): The thickness of the support test piece was measured using a fine thickness measuring machine.

-Porosity (%): Based on ASTM F316-03, the porosity of a support test piece having a radius of 25 mm was measured using a Capillary Composer from PMI.

-Air permeability (Gurley, sec / 100 ml): 100 ml of air passes through a support test piece with a diameter of 29.8 mm at a measurement pressure of 0.025 MPa using the Asahi Seiko Co., Ltd. Densometer EGO2-5 model. The time to do was measured.

-Crosslink degree (gel fraction,%): Support test piece 100 mg (W ₀ ) was immersed in 1,2,4-trichlorobenzene and then heat-treated at 130 ° C. for 2 hours. After separating the test piece, it was dried at 50 ° C. for 24 hours, the weight (W) of the dried test piece was measured, and the degree of cross-linking was calculated using the following formula (formula 1).

Equation 1

-Tensile strength (kgf / cm ² ): Using a tensile strength measuring machine, stress was applied to a support test piece having a size of 20 × 200 mm, and the applied stress was measured until the test piece broke.

-Tensile elongation (%): Using a tensile strength measuring machine, apply stress to a support test piece with a size of 20 x 200 mm and measure the maximum length extended until the test piece breaks, and calculate as follows. The tensile elongation was calculated using the equation (Equation 2).

Equation 2

In the above formula, l ₁ is the horizontal or vertical length of the test piece before stretching, and l ₂ is the horizontal or vertical length of the test piece immediately before breaking.

-Perforation strength (gf): Using the KES-G5 model of the perforation strength measuring machine manufactured by KATO TECH, a support test piece having a size of 100 x 50 mm and a stick (Stic) having a diameter of 0.5 mm at 0.05 cm / sec. A force was applied at a rate and the force applied at the time the test piece was perforated was measured.

-Meltdown temperature (° C.): The test piece is heated at a rate of 5 ° C./min after applying a force of 0.01 N to the support test piece using a thermomechanical analysis. The degree of deformation of was measured. The temperature at which the test piece was broken was defined as the meltdown temperature.

-Heat shrinkage rate (%): A support test piece having a size of 200 x 200 mm was placed between A4 papers in an oven at 120 ° C. for 1 hour, left to stand, and then cooled at room temperature to allow the test pieces to be horizontal and vertical. The contracted length in the direction was measured, and the heat shrinkage rate was calculated using the following formula (Equation 3).

Equation 3

In the above formula, l ₃ is the horizontal or vertical length of the test piece before shrinkage, and l ₄ is the horizontal or vertical length of the test piece after shrinkage.

The porous support produced by Production Example 1-2 was photographed by SEM and shown in FIG. In addition, the physical properties of the supports manufactured by the above-mentioned production examples and comparative production examples were measured, and the results are shown in Tables 1 and 2 below.

Experimental Example 2
The paraffin oil regenerated after extraction in the dichloromethane leaching tanks of Production Examples 1-2 and Comparative Production Examples 1-1 and 1-2 was subjected to inductively coupled plasma emission spectrometry (ICP). The results are shown in Table 3 below.

Referring to Table 3 above, in Production Example using silane-modified polyolefin and Comparative Production Example 1-1, the Si content per 1 kg of paraffin oil is 5 mg or less, which falls within the measurement error, but trimethoxyvinylsilane is used. In Comparative Production Example 1-2, 220 mg of Si was detected per 1 kg of paraffin oil. Further, as a result of additional analysis of the paraffin oil of Comparative Production Example 1-2, it was confirmed that a large number of silanes were grafted to the paraffin oil in addition to polyethylene in the grafting process of trimethoxyvinylsilane. The silane-modified paraffin oil could not be regenerated, and the entire amount was discarded.

Experimental Example 3
The porous support produced by the production example and the comparative production example is divided into three equal parts in the lateral direction (TD), a support test piece is extracted at each portion, and the degree of cross-linking, drilling strength and meltdown temperature are measured. It is shown in Table 4 below. In Table 4 below, L means a support on one side, R means a support on the other side, and M means a value measured by a test piece of a support on the central side. The maximum difference is the larger of the differences between the M value and the L or R value.

Experimental Example 4
At the time of crosslinking by the production example and the comparative production example, the gel fraction of the support was measured by the crosslinking time to evaluate the reaction rate according to the crosslinking method and conditions, and the results are shown in Table 5 below.

With reference to Table 5, in the case of Production Examples 1-5 and 1-6 in which the crosslinking reaction was continuously carried out in a crosslinking tank carrying propylene glycol (boiling point: 188.2 ° C.), Comparative Production Example 1- Compared to 4, the time required to achieve a degree of cross-linking of about 70% is shortened to a maximum of 1/3 or less, and ethylene glycol (boiling point: 197.3 ° C.), which has a higher boiling point than propylene glycol, is supported. In the case of Production Examples 1-7 and 1-8 in which the cross-linking reaction was continuously carried out in the cross-linking tank, it took the maximum time to achieve a degree of cross-linking of about 60% as compared with Comparative Production Example 1-5. It was shortened to 1/10 or less.

Manufacturing example 2
In order to modify the surface of the porous support of Production Examples 1-1 to 1-8, it was treated with vacuum plasma. Prior to plasma treatment, the porous support was sandwiched between frames that could be kept flat and spread and purged with nitrogen to remove impurities on the support.

The size of the chamber of the device for vacuum plasma processing is 420 mm in width, 430 mm in depth, and 270 mm in height. I used the one. A porous support was placed parallel to the electrode plate at a point 2 mm away from the electrodes in the 2nd, 3rd, and 4th stages from the bottom electrode, and vacuum conditions were created until the pressure inside the chamber became 0.1 torr.

A brom gas (Br ₂ , process gas) having the composition shown in Table 6 below was flowed into the chamber at a flow rate of 30 sccm, and the chamber internal pressure was maintained at 0.2 torr for 2 minutes for purging. Further, a high frequency power source having a frequency of 13.56 KHz was applied at an output of 300 W so that plasma conditions were created inside the chamber for 2 minutes so that the brom functional group adhered to the porous support.

The upper and lower surfaces of the porous support are turned over and positioned inside the chamber by the method as described above, and the same process is repeated to uniformly plasma-treat both sides of the porous support, that is, the upper surface and the lower surface. I did it.

In order to replace the brom functional group bonded to the plasma-treated porous support with an amine group, the Sn 2 reaction ( _SN 2 reaction for 48 hours under the conditions of each substance and temperature and atmospheric pressure shown in Table 6 below (Table 6 below). It was subjected to a bimolecular nucleophilic substitution reaction), and then washed with ethanol and distilled water. Hereinafter, for stable ionization of the functional group, a solution of 20% by weight methyl iodide (Iodomethane, CH ₃ I) and 80% by weight n-butanol (n-butanol, CH ₃ (CH ₂ ) ₃ OH) was added at 35 ° C. , The amine group was quaternized by reacting at atmospheric pressure for 48 hours.

Experimental Example 5
The surface of the porous support produced in Production Example 1-1 is modified by plasma and post-treatment, and the surface zeta using the flow potential method is used to quantify the charge characteristics of the modified surface. The potential (zeta potential, mV) was measured and the results are shown in Table 6 below.

Referring to Table 6 above, the porous supports (Comparative Production Examples 2-1 and 2-2) which are not subjected to plasma surface treatment and / or S _S 2 reaction are very hydrophobic and the surface is completely charged. On the other hand, in the case of Production Examples 2-1 and 2-2 that have undergone brom plasma treatment and the _Sn 2 reaction, it can be seen that the surface is positively charged and is significantly converted to hydrophilicity.

In particular, the porous support of Production Example 2-2 that has undergone the quaternization reaction has a higher zeta potential than that of Production Example 2-1 through which stable ionization by quaternization of the amine group becomes possible. You can confirm that.

Production Example 3: Production of aminoated PAES (polyvalent PAES) A gas inlet, a thermometer, a Dean Stark trap, a cooler and a stirrer were installed in a 100 mL round flask with a branch, and air and impurities were removed in a nitrogen atmosphere for several minutes. After that, 4,4'-dichlorodiphenyl sulfone 3.4460 g, 4,4'-biphenol (BP) 3.7242 g, disulfonated dichlorodiphenyl sulfone 3.9301 g, K ₂ CO ₃ 3.1787 g and NMP 44.4 mL, toluene. 22.2 mL (NMP / toluene = 2/1, v / v) was added, and the monomer was dissolved while stirring at 80 ° C. or higher for 1 hour.

After that, after raising the temperature of the reaction solution to 160 ° C., the reaction product water was removed while refluxing with toluene for 4 hours, and then the temperature was further raised to 190 ° C. with a Dean-Stark trap. Residual toluene was completely removed and reacted for 24 hours. When the reaction was completed, the reaction solution was diluted with NMP, filtered, and then poured into water to precipitate in the form of swollen fibers and filtered. After that, the obtained reaction product was dried in a vacuum drier at 120 ° C. for 24 hours to obtain a polymer polymer.

After installing a mechanical stirrer, a gas inlet, a condenser and a constant temperature bath for setting the temperature, 100 g of the obtained polymer was charged into a 1 L capacity 4-port flask. After that, the polymer was sufficiently dissolved in 425.8 mL of 1,1,2,2-tetrachloroethane (TCE, 1,1,2,2-tetrachloroethane) so that the polymer content was 12.8% by weight. The constant temperature bath was set to 40 ° C., 8.233 g of the reaction catalyst ZnCl ₂ was added, and after stirring for 30 minutes, 103.0 mL of chloromethyl methyl ether (CMME) was added using a dropping funnel.

The amount of chloromethyl methyl ether added was calculated as 5 times the number of moles of CMME to react per unit mole and added.

After vigorous reaction for 4 hours while injecting a dry inert gas through the gas inlet, the product is filtered to precipitate in excess methanol and the precipitated chloromethylated polyarylene ethylene sulfone pulverized. Then, it was washed with ethanol and deionized water several times. The washed chloromethylated polyarylene ethylene sulfone was dried in a vacuum oven at 90 ° C. for 12 hours or more.

200 g of the produced chloromethylated polyarylene ether sulfone was placed in a 2 L volume 4-necked flask equipped with a mechanical stirrer, and 12.5% by weight was added to 1489.4 mL of dimethylacetamide (DMAc, N, N-dimethylateamide). Dissolved in. When 366 mL of trimethylamine is added dropwise to the reactor using a dropping funnel, the amount of substance added is 4 times or more the number of moles of trimethylamine (TMA) that reacts per number of repeating units of chloromethylated polyether sulfone. The reaction was carried out for 12 hours to prepare an anionic conductive substance solution.

The porous support of Production Example 1-1 was plasma-treated by Production Example 2-2 and then impregnated with the anion conductive substance solution produced in Production Example 3 to produce an anion exchange membrane. ..

An anion exchange membrane was produced by the same method as in Example 1 except that a support not treated with plasma was used.

Comparative Example 1
The commercialized Neosepta® anion exchange membrane (AMX) was washed with deionized water to produce an anion exchange membrane.

Experimental Example 6
The performance and durability of the manufactured anion exchange membrane were evaluated by the following methods, and the results are shown in Table 7 below.

-Ion conversion rate (IEC, meq / g): To measure the ion exchange capacity, the sample was immersed in a NaCl solution using the Mohr titration method to add a quaternary ammonium group to -N ⁺ (CH ₃ ). After completely substituting in the form of ₃ Cl, further immersing in a 0.5 M Na ₂ CO ₃ solution to replace with N ⁺ (CH ₃ ) ₃ CO ₃ ⁻ , and 5% potassium dichromate in this solution. After adding 1 to 2 drops of the solution, the solution was added dropwise until a reddish brown precipitate was formed on AgNO ₃ , the amount of consumed AgNO ₃ was determined, and the ion exchange capacity of the anion exchange membrane was calculated by the following formula 4.

Equation 4

Here, W _dry is the weight of the dried membrane, V _AgNO 3 is the volume of depleted AgNO ₃ , and _CA AgNO 3 is the concentration of the AgNO ₃ solution used for titration.

-Mole absorption rate (water uptake,%): In order to measure the water absorption rate of the anion exchange membrane, the anion exchange membrane is washed with deionized water several times, and the washed anion exchange membrane is washed with deionized water. After soaking in the water for 24 hours and then taking it out to remove the water present on the surface, the weight _Wwet was measured. Next, the same anion exchange membrane was further dried in a vacuum dryer at 120 ° C. for 24 hours, then the weight W _dry was further measured, and the water absorption rate was calculated using the following formula 5.

Equation 5

-Dimensional stability (ΔΔΔ%): Dimensional stability is the same as the method for measuring water absorption, and instead of weight, the length, thickness, and volume change of the anion exchange membrane are measured, and the following formula is used. The dimensional change rate was calculated using 6, 7 and 8.

Equation 6

Equation 7

Equation 8

-Membrane resistance (Resistance, Ω.cm ² ): Electrical resistance is applied to the anion exchange membranes produced in Examples and Comparative Examples using a measuring device (Neoscience VSS-300 Impedance / Gain-phase analyze). It was measured. The electrical resistance was measured by the AC impedance measurement method. After the anion exchange membranes were sufficiently immersed in 2M NaCl solution, the electrical resistance was measured using a clip cell.

Response (Ω.cm ² ) = (r1 _- r2) _* S

Here, r ₁ is the measured resistance value, and r ₂ is the resistance value when there is no film. S is the area of the clip cell (cm ² ).

Referring to Table 7 above, the anion exchange membrane obtained by using the porous support of Production Example 1-1 is compared with the commercial anion exchange membrane of Comparative Example 1 regardless of the presence or absence of plasma treatment. The water absorption rate and ion conversion rate are excellent, and in particular, the dimensional stability is greatly improved.

Comparing the results of Examples 1 and 2, the anion exchange film of Example 1 produced by impregnating a plasma-treated porous support with an anionic conductive substance has an ion conversion rate of about 2. It is higher than the anion exchange film of Example 2 produced by impregnating a porous support that has not undergone plasma treatment with an anion conductive substance at 0.0 meq / g or more, and has excellent ion exchange capacity. At the same time, the dimensional stability was improved.

Further, referring to FIG. 3, the anion exchange membrane of Example 1 is uniformly impregnated with the anion conductive substance, and the water absorption rate is as low as 15% or less. It can be seen that the durability as an anion exchange membrane is excellent.

The above description of the present invention is for illustration purposes only, and a person having ordinary knowledge in the technical field to which the present invention belongs does not change the technical idea or essential features of the present invention. It can be understood that it can be easily transformed into a specific form. Therefore, it should be understood that the examples described above are exemplary in all respects and are not limiting. For example, each component described as a single type may be implemented in a distributed manner, and components described as similarly distributed may also be implemented in a combined form.

The scope of the present invention is set forth by the claims described below, and it should be understood that the meaning and scope of the claims and all modified or modified forms derived from the concept of equality thereof are included in the scope of the present invention.

Claims (9)

A continuous phase matrix containing a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000, a porous support containing a discontinuous phase silane-modified polyolefin crosslinked in the continuous phase matrix, and a porous support.
Contains anionic conductive material impregnated in the pores of the porous support or coated on the surface .
An anion exchange membrane in which the content of the discontinuous phase silane-modified polyolefin in the porous support is 0.1 to 5% by weight . The anion exchange membrane according to claim 1, wherein the silane is vinylsilane containing an alkoxy group. The anion exchange membrane according to claim 1, wherein the anion conductive substance is an aminated polymer. The amineized polymer has the structure of the following chemical formula (Chemical formula 1) and has a structure of the following chemical formula (Chemical formula 1).

In the above formula,
Y is a covalent bond (-), -CO-, -SO _2- or -O-,
Z and D are covalent bonds (-), -O- or -S-, respectively.
C is a covalent bond (-), -C (CH ₃ ) _2- or -C (CF ₃ ) _2- , and
R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ and
R ₂ , R ₃ , and R ₄ are -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or- (CH ₂ ), respectively. ₃ NH (CH ₃ ) Cl,
x and y are arbitrary iteration units, respectively.
x / (x + y) is 0.001 to 1.
The anion exchange membrane according to claim 3 . The amineized polymers include aminoated PAES (polysulfone sulfide), amplified PEK (polysulfone ketone), amplified PEEK (polyphenylene sulfide), amplified PS (polysulfone), and min. The anion exchange membrane according to claim 3 , which is one selected from the group consisting of PPS (polyphenylene sulfide) and a combination of two or more thereof. The porous support further contains an inorganic filler and
The anion exchange membrane according to claim 1, wherein the content of the inorganic filler in the porous support is 10 to 70% by weight. (A) A composition containing 20 to 40 parts by weight of a polyolefin having a weight average molecular weight M _w of 250,000 to 450,000 and 0.1 to 10 parts by weight of a silane-modified polyolefin is processed to obtain a porous support. Manufacturing stage,
(B) A step of cross-linking the silane-modified polyolefin contained in the porous support, and
(C) The step of impregnating the porous support with a solution containing an anionic conductive substance and a solvent.
In step (b), the polyolefin is present in a continuous phase, the crosslinked silane-modified polyolefin is present in a discontinuous phase, and the content of the crosslinked silane-modified polyolefin is 0.1-5% by weight. A method for manufacturing an anion exchange membrane. Before the step (c),
The anion according to claim 7 , further comprising a step of plasma-treating the porous support in the presence of a brom gas and subjecting it to a bimolecular nucleophilic substitution reaction ( _SN 2 reaction) with a compound containing an amine group. A method for manufacturing a replacement membrane. The method for producing an anion exchange membrane according to claim 8 , wherein the plasma treatment is performed for 0.5 to 90 minutes.

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