KR20220072809A - A polymer membrane comprising an amphiphilic branched copolymer, a gas separation membrane comprising the polymer membrane, and a method for manufacturing the polymer membrane - Google Patents

Abstract

The present invention relates to a polymer membrane comprising an amphiphilic branched copolymer, a gas separation membrane comprising the polymer membrane, and a method for manufacturing the polymer membrane, and more particularly, to the side branch of the hydrophobic polymer P (VDF-co-CTFE) main chain. By copolymerizing the side chain of a vinylpyridine-based compound, which is a hydrophilic polymer, to synthesize an amphiphilic cross-linked copolymer, and applying this to a polymer membrane, the structure and pore shape of the membrane can be controlled by the self-assembly of the amphiphilic cross-linked copolymer. In addition, the polymer membrane of the present invention has excellent thermal and chemical stability of the membrane, and can significantly improve the hydrophilicity and gas permeability of the membrane by forming macropores of a lattice structure specifically arranged at regular intervals.

Description

A polymer membrane comprising an amphiphilic branched copolymer, a gas separation membrane comprising the polymer membrane, and a method for manufacturing the polymer membrane membrane}

The present invention relates to a polymer membrane comprising an amphiphilic branched copolymer, a gas separation membrane comprising the polymer membrane, and a method for manufacturing the polymer membrane.

Recently, as a material for water treatment and gas separation, polymer membranes are attracting attention in the field of separation technology. Separation techniques using cryogenic distillation and adsorption techniques are also being developed, but these techniques are capital intensive and involve process complexity. In the past decade or so, membrane technology has undergone great advances due to the discovery of various membranes. In particular, polymer membrane separation has many technical advantages such as high energy efficiency, easy scale-up, simple process, and low operating cost. In addition, the polymer membrane-based separation process does not involve mechanical complexity, so it is safe and environmentally friendly. In addition, due to the various chemical and structural properties of polymers, it is possible to fabricate membranes for different uses, and it is easy to scale up and down the membrane process and integrate it into other separation or reaction processes. Therefore, polymer membranes are considered as promising candidates for industrial separation applications.

The term "amphiphilic polymer" refers to a material in which hydrophilicity and hydrophobicity coexist, and this property imparts self-assembly properties to polymers in nanostructures. The hydrophilic chain provides functionality to the polymer, while the hydrophobic chain serves to provide good chemical stability and mechanical strength. Amphiphilic polymers can exist as block copolymers and branched copolymers, and although block copolymers have a well-ordered microstructure and good physical properties, the synthesis of block copolymers generally involves a multi-step process. In contrast, the branched copolymer has the advantage of being economically advantageous because the synthesis method is simple. Studies have been actively conducted to control the hydrophilicity, structure, and stability of the membrane by using such an amphiphilic polymer as an additive.

Among various commercially available polymers, fluororesins are used in various fields due to their high chemical and physical stability and excellent resistance to denaturation. This characteristic of fluororesin can be attributed to the strong bond between carbon and fluorine. Compared with other hydrocarbon polymers such as polypropylene and polyethylene, poly(vinylidene fluoride) (PVDF) is considered as one of the highly versatile fluororesins due to its high stability, excellent processability, and various applications. The PVDF-based polymer film has excellent thermal and aqueous stability, antioxidant properties, excellent mechanical properties, and good film forming ability due to the strong bonding of C and F. However, PVDF film still faces many technical limitations due to the hydrophobic film.

The most important thing to consider in membrane technology is the control over the structural properties of the membrane. Since membrane fabrication is a very sensitive process, the structure changes depending on several conditions such as thermodynamic and kinetic factors of the phase transition process. In this process, additives have been widely used to control the structure and pores of the membrane because they affect the phase transition process. For example, polyethylene glycol (PEG) is a typical additive and is often used as a pore former in the manufacturing process of a membrane. When PEG is used as an additive, the shape and structure of the membrane vary depending on the molecular weight and capacity of the PEG. However, there are no studies using an amphiphilic polymer as an additive to control the membrane shape and pore shape.

Korean Patent Registration No. 2019-0127524

In order to solve the above problems, an object of the present invention is to provide a polymer membrane including an amphiphilic branched copolymer capable of controlling the structure and pore shape of the membrane by self-assembly.

Another object of the present invention is to provide a gas separation membrane having excellent thermal and chemical stability and improved hydrophilicity, gas permeability and selectivity, including the polymer membrane.

Another object of the present invention is to provide a gas separation device including the gas separation membrane.

Another object of the present invention is to provide a gas collection device including the gas separation membrane.

Another object of the present invention is to provide a method for manufacturing the polymer membrane.

The present invention is a polymer membrane comprising an amphiphilic branched copolymer in which a hydrophilic polymer side chain is copolymerized by atom transfer radical polymerization to a side branch of a hydrophobic polymer main chain. ⑤ It provides a polymer film characterized in that it shows a fourth effective peak and a fifth effective peak, respectively, in the range of 38° to 39°.

In addition, the present invention provides a gas separation membrane including the polymer membrane.

In addition, the present invention provides a gas separation device including the gas separation membrane.

In addition, the present invention provides a gas collection device including the gas separation membrane.

In addition, the present invention comprises the steps of preparing an amphiphilic branched copolymer by adding a hydrophobic polymer, a hydrophilic polymer, a catalyst and a polymerization initiator to a first organic solvent and copolymerizing by atom transfer radical polymerization; preparing a polymer casting solution by dissolving a fluorine-based polymer and the amphiphilic branched copolymer in a second organic solvent; And after applying the polymer casting solution to the substrate, preparing a polymer film by a non-solvent induced phase separation method; provides a method for producing a polymer film comprising a.

The polymer membrane according to the present invention synthesizes an amphiphilic crosslinking copolymer by copolymerizing a hydrophilic polymer vinylpyridine-based compound side chain with a side branch of a hydrophobic polymer P(VDF-co-CTFE) main chain, and applying it to a polymer membrane. The structure and pore shape of the membrane can be controlled by the self-assembly of the type copolymer.

In addition, the polymer membrane according to the present invention has excellent thermal and chemical stability of the membrane, and it is possible to significantly improve the hydrophilicity, gas permeability and selectivity of the membrane by forming macropores of a lattice structure specifically arranged at regular intervals.

The effects of the present invention are not limited to the above-mentioned effects. It should be understood that the effects of the present invention include all effects that can be inferred from the following description.

1 schematically shows a method for non-solvent-induced phase separation of a polymer membrane (a) and a chemical structure (b) of an amphiphilic branched copolymer of the present invention.
Figure 2 shows the FT-IR graph (a), 1H NMR analysis (b) and GPC analysis (c) results of the copolymers prepared in Examples 1 to 3 and Comparative Example 1 of the present invention.
3 shows TEM results of the amphiphilic branched copolymers prepared in Example 1 (d), Example 2 (c), Example 3 (b) and Comparative Example 1 (a) of the present invention.
4 is a graph showing the results of DSC analysis (a) and TGA analysis (b) of the amphiphilic branched copolymers prepared in Examples 1 to 3 and Comparative Example 1 of the present invention.
5 is a polymer membrane prepared in Comparative Example 2 (M1) (a), Comparative Example 3 (M2) (b), Example 4 (M3) (c), Comparative Example 4 (M4) (d) of the present invention. This is a cross-sectional SEM image.
6 is a polymer film prepared in Comparative Example 2 (M1) (a), Comparative Example 3 (M2) (b), Example 4 (M3) (c), Comparative Example 4 (M4) (d) of the present invention. This is a surface SEM image.
7 is a cross-sectional SEM image of the polymer membrane prepared in Comparative Example 4 (M4) (a), Comparative Example 5 (M5) (b), and Comparative Example 6 (M6) (c) of the present invention.
8 is a graph showing FT-IR results for polymer films prepared in Example 4 (M3) and Comparative Example 4 (M4) of the present invention.
9 (a) is an XRD analysis result of the polymer membrane prepared in Example 4 (iii) and Comparative Examples 2 to 4 (i, ii, v), (b) is Examples 4, 5 (i, iii), The results of XRD analysis of the polymer membranes prepared in Comparative Examples 4 and 5 (ii, v) are shown.
10 is a SAXS of the polymer film (a) prepared in Comparative Example 2 (NMP) and Comparative Example 3 (DMF) of the present invention and the polymer film (b) prepared in Example 4 (NMP) and Comparative Example 4 (DMF) of the present invention; It is a graph showing the analysis result.
11 shows the results of measuring the surface contact angle to water for the polymer membranes prepared in Examples 6 to 8 (b, c, d) and Comparative Example 7 (a) of the present invention.
12 is a graph showing the results of measuring pure water permeability over time for the polymer membranes prepared in Examples 6 to 8 (M8, M9, M10) and Comparative Example 7 (M7) of the present invention.

Hereinafter, the present invention will be described in more detail by way of one embodiment.

The present invention relates to a polymer membrane comprising an amphiphilic branched copolymer, a gas separation membrane comprising the polymer membrane, and a method for manufacturing the polymer membrane.

As described above, the existing polymer membranes for gas separation membranes use additives such as polyethylene glycol as pore formers to form pores, but the shape and structure of the membranes vary depending on the molecular weight and capacity of polyethylcolglycol, so there is a limit to its application. there was.

Therefore, in the present invention, an amphiphilic crosslinking type copolymer is synthesized by copolymerizing a hydrophilic polymer vinylpyridine-based compound side chain with a side branch of a hydrophobic polymer P(VDF-co-CTFE) main chain, and applying it to a polymer membrane. The structure and pore shape of the membrane can be controlled by the self-assembly of the copolymer. In addition, the polymer membrane has excellent thermal and chemical stability, and can significantly improve the hydrophilicity, gas permeability and selectivity of the membrane by forming macropores of a lattice structure specifically arranged at regular intervals.

Specifically, the present invention is a polymer membrane comprising an amphiphilic branched copolymer in which a hydrophilic polymer side chain is copolymerized by atom transfer radical polymerization to a side branch of a hydrophobic polymer main chain, and the polymer membrane has an XRD analysis result, 2θ is ④ 26° to 27° It provides a polymer film, characterized in that it shows a fourth effective peak and a fifth effective peak, respectively, in the range and ⑤ 38° to 39° range.

The hydrophobic polymer may be polyvinylidenefluoride-co-chlorotrifluoroethylene (Poly(vinylidenefluoride-co-chlorotrifluoroethylene), P(VDF-co-CTFE)). The polyvinylidenefluoride-co-chlorotrifluoroethylene (Poly(vinylidenefluoride-co-chlorotrifluoroethylene), P(VDF-co-CTFE)) is a polymer that is chemically and thermally stable and has excellent mechanical strength. In addition, the presence of the CTFE branch may serve to form a branched copolymer by bonding other polymer chains by an atom transfer radical polymerization (ATRP) synthesis method.

The hydrophilic polymer is a vinylpyridine-based compound, and specific examples thereof may be 2-vinylpyridine, 4-vinylpyridine, or a mixture thereof, preferably 2-vinylpyridine.

The amphiphilic branched copolymer is one in which the hydrophobic polymer main chain and the hydrophilic polymer side chain are polymerized in a weight ratio of 5:5 to 7:3, preferably 6:4 to 5:5, and most preferably 5:5. can At this time, if the mixing ratio of the hydrophilic polymer side chains is less than 5 weight ratio, further improved microphase separation effect of the polymer membrane cannot be expected, and on the contrary, if it exceeds 3 weight ratio, the microphase separation of the polymer membrane does not sufficiently occur, and the transmittance may be rapidly reduced.

The amphiphilic branched copolymer may have a number average molecular weight (Mn) of 125,000 to 200,000 g/mol, a molecular weight distribution (PDI) of 1.5 to 3, and preferably a number average molecular weight (Mn) of 130,000 to 180,000 g /mol, and may have a molecular weight distribution (PDI) of 1.6 to 2.2, more preferably a number average molecular weight (Mn) of 140,000 to 150,000 g/mol, and a molecular weight distribution (PDI) of 1.65 to 1.8, most preferably Preferably, the number average molecular weight (Mn) may be 145,000 g/mol, and the molecular weight distribution (PDI) may be 1.7.

The amphiphilic branched copolymer may be a compound represented by Formula 1 below.

[Formula 1]

(In Formula 1,

및 탄소수 1 내지 20의 알킬기 중에서 선택되고,R ₁ To R ₄ Are the same as or different from each other, and each independently H, Cl,

and an alkyl group having 1 to 20 carbon atoms;

x, y and z are 100: 10-15: 20-80 as a polymerization molar ratio of each repeating unit,

y' is an integer from 0 to 10.)

중에서 선택되고, R₃ 및 R₄는 서로 동일하고, 각각 독립적으로 H이고, x, y 및 z는 각 반복단위의 중합 몰비로서 100 : 12~14 : 26~60이고, y'는 0 내지 1 의 정수일 수 있다. Preferably, in Formula 1, R ₁ and R ₂ are different from each other, and each independently H, Cl and

selected from, R ₃ and R ₄ are the same as each other, each independently H, x, y and z are 100: 12-14: 26-60 as a polymerization molar ratio of each repeating unit, and y' is 0-1 may be an integer of .

이고, 상기 R₂, R₃ 및 R₄는 각각 H일 수 있다.More preferably, in Formula 1, R ₁ , R ₃ and R ₄ are each H, and R ₂ may be Cl, or R ₁ is

and R ₂ , R ₃ , and R ₄ may each be H.

Most preferably, the amphiphilic branched copolymer may be a compound represented by the following Chemical Formula 1-1.

[Formula 1-1]

(In Formula 1-1, x, y and z are 100: 13: 40-60 as a polymerization molar ratio of each repeating unit.)

The amphiphilic branched copolymer is poly(vinylidene fluoride-co-chlorotrifluoroethylene)-g-poly(2-vinylpyridine)(poly(vinylidene fluoride-co-chlorotrifluoroethylene)-g-(poly( 2-vinyl pyridine), (P(VDF- co- CTFE)- g- P2VP)).

As a result of FT-IR analysis, the amphiphilic branched copolymer may have a peak corresponding to a CF bond in a wavelength range of 1185 to 1205 cm ^-1 , preferably 1197 cm ^-1 .

The amphiphilic branched copolymer can impart high mechanical strength, thermal and chemical stability to the polymer membrane in the case of a hydrophobic polymer main chain, and hydrophilicity, gas permeability and selectivity to the polymer membrane in the case of a hydrophilic polymer side chain. . That is, the amphiphilic branched copolymer may have self-assembly properties due to a structure in which a hydrophilic polymer side chain is grafted onto a side branch of a hydrophobic polymer main chain. Such self-assembly can control the structure and pore shape of the membrane due to microphase separation, and improve thermal and chemical stability. In addition, the hydrophilicity, gas permeability and selectivity of the membrane can be controlled according to the content of the hydrophobic polymer side chain.

In particular, when forming the polymer film, the amphiphilic branched copolymer must be mixed with an N-methyl-2-pyrrolidone (NMP) solvent to form a lattice structure specifically aligned by the strong interaction between the copolymer and the NMP solvent. Large pores are formed, and in the XRD analysis result, 2θ may show a fourth effective peak and a fifth effective peak in the range of ④ 26° to 27° and ⑤ in the range of 38° to 39°, respectively. When the polymer film has a fourth effective peak and a fifth effective peak, gas permeability and selectivity may be remarkably improved.

In addition, when the polymer membrane additionally satisfies all of the conditions for the specific mixing ratio of the amphiphilic branched copolymer and the fluorine-based polymer and the non-solvent-induced phase separation method as well as the selective use of the NMP solvent during film formation, in the XRD analysis result, 2θ is ① 17 A first effective peak, a second effective peak, and a third effective peak may be further seen in the range of ° to 18°, ② in the range of 18.2° to 19°, and ③ in the range of 20° to 21°, respectively.

For these effective peaks, preferably the intensity ratio of (first effective peak)/(second effective peak) is 0.9 to 1.1, and the ratio of the (second effective peak)/(third effective peak) is The intensity ratio is 0.5 to 0.8, the intensity ratio of the (third effective peak)/(the fourth effective peak) is 4.1 to 5.5, and the intensity ratio of the (4th effective peak)/(the fifth effective peak) is 0.9 to 1.3.

That is, when the polymer film has a crystal structure showing such effective peaks and intensity ratios in the XRD analysis result, although not explicitly described in the Examples or Comparative Examples, the mechanical properties of the film are greatly improved and used for a long time of 100 hours or more This is possible, and there is an advantage of excellent thermal stability even at a high temperature of 200 °C.

The polymer film may have a thickness of 30 to 200 μm, preferably 40 to 180 μm, more preferably 50 to 150 μm, and most preferably 60 to 120 μm. If the thickness of the polymer film is less than 30 μm, mechanical properties may be deteriorated because the film thickness is too thin, and it may be difficult to use for a long time. Conversely, if it exceeds 200 μm, the total thickness of the gas separation membrane may become too thick, and the gas separation performance may be rather deteriorated.

The polymer membrane may be for a gas separation membrane, for a water treatment membrane, for an ionic electrolyte membrane, or for an ion exchange membrane, preferably for a gas separation membrane or for a water treatment membrane.

Meanwhile, the present invention provides a gas separation membrane including the polymer membrane.

The gas separation membrane may separate one or more gases selected from carbon dioxide, nitrogen, and methane.

The gas separation membrane may have a nitrogen (N ₂ ) permeability of 3 x 10 ⁴ to 8 x 10 ⁴ GPU, preferably 5 x 10 ⁴ to 7 x 10 ⁴ GPU, and most preferably 6.2 x 10 ⁴ GPU.

In addition, the present invention provides a gas separation device including the gas separation membrane.

In addition, the present invention provides a gas collection device including the gas separation membrane.

In addition, the present invention comprises the steps of preparing an amphiphilic branched copolymer by adding a hydrophobic polymer, a hydrophilic polymer, a catalyst and a polymerization initiator to a first organic solvent and copolymerizing by atom transfer radical polymerization; preparing a polymer casting solution by dissolving a fluorine-based polymer and the amphiphilic branched copolymer in a second organic solvent; And after applying the polymer casting solution to the substrate, preparing a polymer film by a non-solvent induced phase separation method; provides a method for producing a polymer film comprising a.

The first organic solvent is N-methyl-2-pyrrolidinone (N-Methyl-2-pyrrolidinone, NMP), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), dimethylformamide (DMF) and tetrahydro It may be one or more selected from the group consisting of furan (THF), but is not limited thereto. Preferably, the first organic solvent may be N-methyl-2-pyrrolidone, dimethylformamide or a mixture thereof, and most preferably N-methyl-2-pyrrolidone.

In the step of preparing the amphiphilic branched copolymer, the hydrophobic polymer and the hydrophilic polymer are polymerized in a weight ratio of 5:5 to 7:3, preferably 6:4 to 5:5, most preferably 5:5 by weight. may be doing

The catalyst may be at least one selected from the group consisting of CuCl, CuCl ₂ , CuBr and CuBr ₂ , preferably CuCl.

The polymerization initiator is 1,1,4,7,10,10-hexamethylenetriethylenetetramine (1,1,4,7,10,10-Hexamethyltriethylenetetramine, HMTETA), N,N,N',N', N''-pentamethyl diethylenetriamine (N,N,N',N', N''-pentamethyl diethylenetriamine, PMDETA), 4,4'-dimethyl-2,2'-dipyridyl (4,4 '-dimethyl-2,2'-dipyridyl, DMDP), tris(2-aminoethyl)amine (TRE), tris(2-dimethylaminoethyl)amine (tris(2-dimethylaminoethyl) amine, Me6-TREN), 2,2'-Bipy (Bipyridine), N,N,N',N-tetramethylethylenediamine (N,N,N', It may be at least one selected from the group consisting of N-Tetramethylethylenediamine, TMEDA) and 1,4,8,11-tetraazacyclotetradecane (1,4,8,11-tetraazacyclotetradecane, Me4-Cyclam). The polymerization initiator may be HMTETA, PMDETA, or a mixture thereof, and most preferably HMTETA.

In the step of preparing the amphiphilic branched copolymer, atom transfer radical polymerization ( atom transfer radical polymerization (ATRP). At this time, if the polymerization temperature is less than 70 ℃ or the polymerization time is less than 10 hours, cross-linking between the hydrophobic polymer and the hydrophilic polymer may not be sufficiently achieved. If the crosslinking occurs excessively, the thermal and chemical stability of the obtained amphiphilic branched copolymer may be deteriorated.

In the step of preparing the amphiphilic branched copolymer, the hydrophobic polymer main chain and the hydrophilic polymer side chain form an amphiphilic polymer through an atom transfer radical polymerization reaction, so that it can have nano-unit self-assembly.

The second organic solvent may be N-methyl-2-pyrrolidinone (N-Methyl-2-pyrrolidinone, NMP). In particular, the NMP solvent may play an important role in controlling the structure of the polymer membrane and forming pores. As described above, when the NMP solvent is used as the second organic solvent, there is a certain gap on the surface of the polymer membrane due to the strong interaction between the amphiphilic branched copolymer and the NMP solvent, unlike the conventional dimethylformamide (DMF) solvent. It is possible to significantly improve the hydrophilicity, gas permeability and selectivity of the membrane by forming macropores of a specifically ordered lattice structure. If dimethylformamide (DMF) solvent is used as the second organic solvent, macropores are irregularly formed in the polymer membrane, so that it is difficult to control the structure and pore shape of the membrane.

The fluorine-based polymer may be poly(vinylidene fluoride-co-chlorotrifluoroethylene, P(VDF- co -CTFE)). As described above, the P( VDF- co -CTFE) polymers have higher chemical and thermal stability than polymers such as polysulfone and polyethersulfone, which are generally used as supports, and have excellent mechanical strength.

The polymer casting solution contains the fluorine-based polymer and the amphiphilic branched copolymer in a weight ratio of 9.5:0.5 to 6:4, preferably 9:1 to 7:3 by weight, more preferably 9:1 to 8:2 by weight, Most preferably, it may be mixed in a 9:1 weight ratio. At this time, if the mixing ratio of the amphiphilic branched copolymer is less than 0.5 weight ratio, it may be difficult to control the structure and pore shape of the polymer membrane.

In the step of preparing the polymer membrane, a non-solvent induced phase separation (NIPS) method dissolves a polymer in a solvent capable of dissolving the polymer so that a good solvent and a non-solvent are polymers. The mutual exchange in the solution induces liquid-solid phase separation and solidification to form a porous polymer membrane.

1 schematically shows a method for non-solvent-induced phase separation of a polymer membrane (a) and a chemical structure (b) of an amphiphilic branched copolymer of the present invention. Referring to FIG. 1 (a), it shows a process of forming a polymer film by a non-solvent-induced phase separation method by mutual exchange of a good solvent and a non-solvent in the polymer casting solution. In addition, (b) shows the chemical structure of the amphiphilic branched copolymer, and shows a structure in which a hydrophilic polymer side chain is copolymerized with a hydrophobic polymer main chain side branch.

In particular, although not explicitly described in the following Examples or Comparative Examples, in the method for producing a polymer membrane according to the present invention, the type of the first organic solvent, the type and mixing ratio of the hydrophobic polymer and the hydrophilic polymer, the catalyst and the polymerization initiator Carbon dioxide ( CO ₂ ) permeability, nitrogen (N ₂ ) permeability, carbon dioxide/nitrogen (CO ₂ /N ₂ ) selectivity and carbon dioxide/methane (CO ₂ /CH ₄ ) selectivity were evaluated.

As a result, it was confirmed that, unlike in other conditions and different numerical ranges, when all of the following conditions were satisfied, excellent gas separation performance (permeability and selectivity) was maintained for a long time in all pressure ranges, unlike conventional membranes.

① The first organic solvent is N-methyl-2-pyrrolidone (NMP), ② The hydrophobic polymer is polyvinylidene fluoride-co-chlorotrifluoroethylene (P(VDF-co-CTFE)) , ③ the hydrophilic polymer is 2-vinylpyridine, ④ preparing the amphiphilic branched copolymer is to polymerize the hydrophobic polymer and the hydrophilic polymer in a weight ratio of 6:4 to 5:5, ⑤ the catalyst is CuCl , ⑥ the polymerization initiator is 1,1,4,7,10,10-hexamethylenetriethylenetetramine (HMTETA), ⑦ the step of preparing the amphiphilic branched copolymer is 18 to 100 ℃ at 80 to 100 ℃ Atom transfer radical polymerization for 22 hours, ⑧ the second organic solvent is N-methyl-2-pyrrolidone (NMP), ⑨ the fluorine-based polymer is poly(vinylidene fluoride-co-chlorotrifluoroethylene) ) (P(VDF- co -CTFE)), and ⑩ the polymer casting solution may be mixed with a fluorine-based polymer and the amphiphilic branched copolymer in a weight ratio of 9:1 to 8:2.

However, when any one of the ten conditions was not satisfied, the gas separation performance was abruptly deteriorated as the pressure increased, and the gas separation performance did not last for a long time either.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited by the following examples.

Example 1: P(VDF- co -CTFE)- g Preparation of -P2VP(5:5) copolymer

(1) P(VDF- co -CTFE)- g -P2VP copolymer synthesis

[Scheme 1]

(In Scheme 1, R ₁ , R ₃ and R ₄ are each H, R ₂ is Cl, x, y and z are 100: 13: 60 as a polymerization molar ratio of each repeating unit, and y' is 0 .)

Using P(VDF- co -CTFE) and 2VP (2-vinylpyridine) as monomers, respectively, atom transfer radical polymerization (ATRP) using chlorine groups present in the CTFE chain was performed to P(VDF- co -CTFE). )- g -P2VP was synthesized. Specifically, 3 g of P(VDF- co -CTFE) was dissolved in 50 mL of NMP (N-Methyl pyrrolidone) at 70 °C. After a uniform solution was prepared, 2VP 3 g, CuCl 0.24 g, and HMTETA (1,1,4,7,10,10-Hexamethyltriethylenetetramine) 0.66 mL were added, and the flask was sealed with a rubber stopper. After purging with nitrogen for 40 minutes, the reaction was performed in an oil bath at 90° C. for 20 hours. After the reaction, the resultant was precipitated in methanol, and then re-dissolved in NMP to remove unreacted substances remaining in the solution and re-precipitated in methanol. This process was performed three times, and each amphiphilic branched copolymer (P(VDF- co -CTFE)- g -P2VP(5:5) copolymer) was synthesized by drying in a vacuum oven to remove the remaining solvent.

Examples 2, 3 and Comparative Example 1: P (VDF- co -CTFE)- g -Preparation of P2VP copolymer

P(VDF- co -CTFE) -g was carried out in the same manner as in Example 1, except that P(VDF- co -CTFE) and 2VP(2-vinylpyridine) were respectively mixed in the weight ratio as shown in Table 1 below. -P2VP(x:y) polymer membrane was prepared.

division 2VP dosage P(VDF- co -CTFE):P2VP weight ratio Example 1
(P(VDF- co -CTFE)- g -P2VP(5:5)) 3 g 5:5 Example 2
(P(VDF- co -CTFE)- g -P2VP(6:4)) 2 g 6:4 Example 3
(P(VDF- co -CTFE)- g -P2VP(7:3)) 1.3 g 7:3 Comparative Example 1
(P(VDF- co -CTFE)) - 1:0

Example 4 and Comparative Examples 2 to 6: P (VDF- co -CTFE)- g -P2VP polymer film production

A porous P(VDF- co -CTFE) -g -P2VP polymer membrane was prepared through nonsolvent induced phase separation (NIPS). As shown in Table 2 below, 3 mL of NMP solvent or DMF solvent and P(VDF- co -CTFE) polymer and P(VDF- co -CTFE) -g -P2VP of Example 1 at 70 ° C. (5:5 ) copolymer was added in the weight ratio shown in Table 2 below to prepare a polymer solution. At this time, the polymer solution was then left at room temperature for 1 hour to eliminate air bubbles, and then cast on a glass plate using a 200 μm doctor blade. After exposure to air for 30 seconds, the glass plate on which the polymer was cast was immersed in a non-solvent, ultrapure water bath at 20° C. for phase transition. After being placed in an ultrapure water bath for one day, each P(VDF- co -CTFE) -g -P2VP polymer film having a thickness of 60 to 120 μm was obtained by removing it from the glass plate. The prepared polymer membrane was stored in ultrapure water for one day to remove impurities, and then retrieved.

division P(VDF- co -CTFE)(x), g P(VDF- co -CTFE):P2VP(5:5)(y), g weight ratio
(x:y) non-solvent good solvent Comparative Example 2 (M1) 0.75 - 1:0
D.I. Water NMP Comparative Example 3 (M2) 0.75 - 1:0 DMF Example 4 (M3) 0.675 0.075 9:1 NMP Comparative Example 4 (M4) 0.675 0.075 9:1 DMF Example 5 0.6 0.15 8:2 NMP Comparative Example 5 (M5) 0.6 0.15 8:2 DMF Comparative Example 6 (M6) 0.525 0.225 7:3 DMF

Experimental Example 1: Composition of the amphiphilic branched copolymer, FT-IR, ^One H NMR, GPC and TEM analysis

Compositions and Fourier-transform infrared (FT-IR), ¹ H NMR, gel permeation chromatography (GPC) and transmission electron microscopy (TEM) of the amphiphilic branched copolymers prepared in Examples 1 to 3 and Comparative Example 1 was used to analyze the structure. The results are shown in Table 3 and FIGS. 2 and 3 .

2 shows FT-IR graphs (a), 1H NMR analysis (b), and GPC analysis (c) results of the copolymers prepared in Examples 1 to 3 and Comparative Example 1. FIG. Referring to (a) of FIG. 2, in the case of Comparative Example 1 (P(VDF- co -CTFE)), a strong band was observed at 1178 cm ^-1 , which is due to stretching vibrations of the CF bond. did it Another strong band was also observed at 1400 cm ^-1 , which is due to the CH bond of the P(VDF- co -CTFE) main chain.

On the other hand, in the case of Example 1 (P(VDF- co -CTFE) ^- g -P2VP(5:5)), the stretching vibration for the CC bond of the aromatic group of the P2VP side chain according to the polymer polymerization was 1591 cm- ¹ was observed. The band appears at 1586 cm ⁻¹ in the case of 2VP, but shifts to a higher wavenumber at 1591 cm ⁻¹ after polymerization into P(VDF- co -CTFE) -g -P2VP copolymer, which is close to This is due to specific interactions between the 2VP groups. Through this FT-IR graph, it was confirmed that the synthesis of the P(VDF- co -CTFE) -g -P2VP copolymer was successfully performed. Additionally, P2VP homopolymer may have been generated during the synthesis, but it was found that it was removed by dissolving in methanol during the precipitation process.

In addition, referring to FIG. 2(b), it was confirmed that the P(VDF- co -CTFE) -g -P2VP copolymers prepared in Examples 1 to 3 were successfully synthesized through ¹ H NMR. Two multiple signals were observed at 2.2 ppm to 2.7 ppm and 2.7 ppm to 3.2 ppm, which are the tail-tail (-CF ₂ -CH ₂ -CH ₂ -CH ₂ ) present in the P(VDF- co -CTFE) main chain. -) and head-tail(-CF ₂ -CH ₂ -CF ₂ -CH ₂ -) respectively. In addition, the signal appearing at 3.0 ppm to 3.3 ppm is due to -CF ₂ -CH ₂ -CFCl-CF ₂ - of the VDF adjacent to the CTFE.

In addition, the two signals appearing at 6.5 ppm and 8.4 ppm are signals displayed by the P2VP side chain polymerized on the P(VDF- co -CTFE) main chain, and these signals are due to hydrogen present in the pyridine ring of the P2VP side chain. As the amount of P2VP increased, it was confirmed that the two signals became more prominent. In addition, by integrating and comparing the area of the signal at 2.3 ppm and 2.9 ppm corresponding to the P(VDF- co -CTFE) main chain and the signal at 6.5 ppm and 8.4 ppm corresponding to the P2VP side chain, P(VDF- co -CTFE) )- g -P2VP composition was obtained and summarized in Table 3 below.

In addition, the number of each of Comparative Example 1 (P(VDF- co -CTFE)) and Example 1 (P(VDF- co -CTFE) -g -P2VP(5:5)) of FIG. It is the result of measurement using GPC to confirm the average molecular weight (number-average molecular weight, Mn) and molecular weight distribution (polydispersity index, PDI). Looking at this, both number average molecular weight and molecular weight distribution were increased in P(VDF- co -CTFE)- g -P2VP, indicating successful polymer polymerization through ATRP.

Table 3 shows the signals at 2.3 ppm and 2.9 ppm corresponding to the P(VDF- co -CTFE) main chain and 6.5 ppm and 8.4 ppm signals corresponding to the P2VP side chain with reference to FIG. 2(b). The composition of the P(VDF- co -CTFE) -g -P2VP copolymer prepared in Examples 1 to 3 and Comparative Example 1 calculated by integrating the area is shown. Through this, the polymerization molar ratio of x, y and z was confirmed for each P(VDF- co -CTFE) -g -P2VP copolymer.

3 shows TEM results of the amphiphilic branched copolymers prepared in Example 1(d), Example 2(c), Example 3(b) and Comparative Example 1(a). In the TEM image of FIG. 3 , a region having a high electron density is dark, while a region having a low electron density is bright. Referring to FIG. 3 , a relatively less aligned structure was observed in Comparative Example 1(a). On the other hand, in the case of Example 1 (d), Example 2 (c), and Example 3 (b), it was confirmed that the dark region and the bright region showed a clearly contrasted nanostructure. As the amount of polymerized P2VP side chains on the P(VDF- co -CTFE) main chain increases, a clear contrasting ordered nanostructure is formed, which is related to the hydrophobic P(VDF- co -CTFE) main chain and the hydrophilic P2VP side chain. This is because microphase separation occurs by

Experimental Example 2: DSC and TGA analysis of amphiphilic branched copolymers

DSC and TGA analysis was performed on the amphiphilic branched copolymers prepared in Examples 1 to 3 and Comparative Example 1 to analyze the structure and thermal properties of the membrane. The results are shown in FIG. 4 .

4 is a graph showing the results of DSC analysis (a) and TGA analysis (b) of the amphiphilic branched copolymers prepared in Examples 1 to 3 and Comparative Example 1. FIG. Referring to (a) of FIG. 4 , in the case of Comparative Example 1 (P(VDF- co -CTFE)), it was confirmed that the Curie transition temperature was observed at 92°C and the melting point was observed at 166°C.

On the other hand, in the case of Examples 1 to 3, a strong thermal transition peak at 88° C. appears due to the grafted P2VP chain, which is due to the glass transition temperature of the P2VP chain. These results are clear evidence that a microphase-separated structure is formed due to the amphiphilic nature of the polymer due to the hydrophobic P(VDF- co -CTFE) main chain and the hydrophilic P2VP side chain. Due to this, it was confirmed that the synthesis of the P(VDF- co -CTFE) -g -P2VP copolymer was successful. In addition, the melting point was increased from 166 °C to 170 °C by the P2VP chain, indicating that the thermal properties of the synthetic polymer were improved due to polymer polymerization.

In addition, referring to FIG. 4B , in the case of Example 1 (P(VDF- co -CTFE) -g -P2VP(5:5)), there was no weight loss up to about 300°C. These results suggest that the P(VDF- co -CTFE) -g -P2VP copolymer has excellent thermal stability and can be applied to various fields requiring high thermal properties at the same time.

Experimental Example 3: Structural Analysis of Polymer Membrane

The structures of the polymer films prepared in Example 4 and Comparative Examples 2 to 6 were analyzed using scanning electron microscopy (SEM). The results are shown in FIGS. 5, 6 and 7 .

5 is a cross-sectional SEM of the polymer membrane prepared in Comparative Example 2 (M1) (a), Comparative Example 3 (M2) (b), Example 4 (M3) (c), and Comparative Example 4 (M4) (d). It is an image. Referring to FIG. 5 , each of the prepared polymer films was formed by being divided into a dense and thin surface layer having selectivity and a support layer having a finger-like or spong-like structure. It was found that this asymmetric structure was formed by the exchange between the nonsolvent and the solvent during the phase transition. It was confirmed that the exchange rate between the solvent and the nonsolvent became slow after the dense upper surface layer was formed on the surface, and then the lower support layer was formed.

In FIG. 5, when comparing Comparative Example 2 (M1) (a) and Comparative Example 3 (M2) (b), which are polymer films made of pure P (VDF- co -CTFE) copolymer, M1 (a) using NMP It was confirmed that macrovoids were more developed in Since the structure of the membrane is determined by the exchange rate between the solvent and the non-solvent during phase transition, it was largely influenced by the interaction between the solvent and the non-solvent. The better interactions existed, the more macropores formed. On the other hand, in the case of M2(b), the polymer chains were entangled in the DMF solvent, and delayed demixing occurred, so that fewer pores were formed.

For these results, the Hansen dissolution factor gives a numerical value of the degree of interaction, which can be a good measure of solubility between different substances. The dissolution factor consists of the following order of water (47.9 MPa ^1/2 ) >> DMF (24.9 MPa ^1/2 ) > NMP (23.0 MPa ^1/2 ). When predicted as a dissolution factor, the interaction between water and DMF was greater than the interaction between water and NMP, and the exchange rate between solvent and nonsolvent was also faster, so it was expected that more macropores would be observed in the membrane prepared using DMF. . However, the opposite result was confirmed. In other words, it was found that the opposite result was different from the expected due to the interaction between the polymer and the solvent. Assuming that the dissolution factor of P(VDF- co -CTFE) is similar to that of PVDF (17.5 MPa ^1/2 ), a similar polymer, NMP has good interaction with P(VDF- co -CTFE). As a result, the polymer chains are more unraveled in the NMP solvent and exist in a highly stretched state, which causes immediate demixing.

Also, in the case of Example 4(M3)(c), a finger-like structure having a large number of macropores was observed. On the other hand, in Comparative Example 4 (M4) (d), a sponge-like structure with reduced macropores was observed, and very few pores were formed at the lower end of the membrane. This difference in cross-sectional structure confirmed two facts. First, the structure of the membrane during the phase transition is greatly affected by the solvent. Second, the introduction of the amphiphilic P(VDF- co - CTFE ) -g - P2VP copolymer promotes the development of well-ordered porous finger-like structures, which It was found that it was due to self-assembly and hydrophilicity.

6 is a surface SEM of the polymer film prepared in Comparative Example 2 (M1) (a), Comparative Example 3 (M2) (b), Example 4 (M3) (c), Comparative Example 4 (M4) (d). It is an image. Referring to FIG. 6, results similar to those of FIG. 5 were obtained, in particular, Example 4 (M3)(c) using P(VDF- co -CTFE) -g -P2VP copolymer as an additive for pore formation and Comparative Example 4 (M4) (d) compared to Comparative Example 2 (M1) (a) and Comparative Example 3 (M2) (b) prepared using only P (VDF- co -CTFE) was confirmed to be increased. These results indicate that the self-assembly and hydrophilicity of the amphiphilic P(VDF- co -CTFE) -g -P2VP copolymer play an important role as a pore-forming agent.

7 is a cross-sectional SEM image of the polymer membrane prepared in Comparative Example 4 (M4) (a), Comparative Example 5 (M5) (b), and Comparative Example 6 (M6) (c). Referring to FIG. 7 , as the content of the P(VDF- co -CTFE) -g -P2VP copolymer increased, a porous structure with many macropores was well developed. These results support the fact that the P(VDF- co -CTFE) -g -P2VP copolymer has an amphiphilic property due to the hydrophilic P2VP chain and self-assembly occurs.

Experimental Example 4: FI-IR analysis of polymer film

The structures of the polymer films prepared in Example 4 (M3) and Comparative Example 4 (M4) were analyzed using Fourier-transform infrared (FI-IR), and the results are shown in FIG. 8 .

8 is a graph showing FT-IR results for the polymer films prepared in Example 4 (M3) and Comparative Example 4 (M4). Referring to (a) of FIG. 8, in the case of Example 4 (M3) using the NMP solvent, the 1179 cm ^-1 band shown by the CF bond of P(VDF- co -CTFE) was 1197 cm ^-1 . movement was confirmed. This band shift is a direct indicator of the existence of a strong interaction between the P(VDF- co -CTFE) -g -P2VP copolymer and the NMP solvent. On the other hand, referring to (b) of FIG. 7, when the polymer membrane was prepared using the DMF solvent, it was confirmed that the position of the band due to the CF bond did not change, which was P(VDF- co -CTFE)- g - This means that the interaction between P2VP and DMF solvent is weak.

Experimental Example 5: XRD analysis of polymer membrane

The structural characteristics of each polymer membrane prepared in Examples 4 to 5 and Comparative Examples 2 to 5 were analyzed by XRD analysis, and the results are shown in FIG. 9 .

9 (a) is an XRD analysis result of the polymer membrane prepared in Example 4 (iii) and Comparative Examples 2 to 4 (i, ii, v), (b) is Examples 4, 5 (i, iii), The results of XRD analysis of the polymer membranes prepared in Comparative Examples 4 and 5 (ii, v) are shown. Referring to (a) and (b) of FIG. 9, two peaks (2θ = 17.9°, 20.0°) were observed in all polymer films regardless of the solvent, which is the Miller index of P(VDF- co -CTFE). (100) and (110) indicated by the α-crystal plane. When comparing the two solvents, Comparative Example 2(i), Example 4(iii) and Example 4(i) in FIG. 9(a) using the NMP solvent and Example 4(i) in FIG. 9(b) Only in Example 5(iii), a specific peak at 26.7 ^o appears, which is due to the α(021) plane. These results imply that both P(VDF- co -CTFE) and P(VDF- co -CTFE) -g -P2VP have specific crystal structures only when NMP solvent is used. These peaks appear due to the pseudo-hexagonal dense structure of the helical chain with various angles of the transverse axis and the chain axis disorder.

In addition, the peak at 38.84 ^o is the P (VDF- co -CTFE) - g -P2VP copolymer and the NMP solvent in Example 4 (iii) and (b) in (a) above to form a polymer film It appears only in Examples 4(i) and 5(iii), which is due to the (002) reflection of the α-crystal plane. Polymer dispacing was calculated using Bragg's equation, and the peaks at 26.7 ^o and 38.8 ^o have values of 3.34 ㅕ and 2.32 ㅕ, respectively. This result means that the amphiphilic P(VDF- co -CTFE) -g -P2VP copolymer forms a specific crystal structure differently from the P(VDF- co -CTFE) copolymer.

Experimental Example 6: SAXS analysis of polymer membrane

The polymer membranes prepared in Example 4 and Comparative Examples 2 to 4 were subjected to SAXS analysis to analyze the microstructure of the membrane. The results are shown in FIG. 10 . The SAXS analysis method is a useful analysis method for confirming the dense structure of the nanoscale.

10 is a SAXS analysis result of the polymer film (a) prepared in Comparative Example 2 (NMP) and Comparative Example 3 (DMF) and the polymer film (b) prepared in Example 4 (NMP) and Comparative Example 4 (DMF) is a graph showing Referring to (a) of FIG. 10, the polymer membranes of Comparative Example 2 (NMP) and Comparative Example 3 (DMF) did not show a clear peak, which is due to the solvent difference. It means to have an ordered structure.

On the other hand, referring to FIG. 10 (b), the polymer film of Example 4 (NMP) showed a broad peak at q = 0.3 nm ^-1 , and the presence of this peak formed a microphase-separated structure in the polymer. means In addition, as a result of obtaining dispacing, which is the average distance between domains, using the Bragg equation, a value of 20.9 nm was obtained. These SAXS results indicate that a specific microphase-separated structure is formed in the polymer membrane using the P(VDF- co -CTFE) -g -P2VP copolymer only when the NMP solvent is used. These results were also consistent with the aforementioned FT-IR results of FIG. 8 and the XRD results of FIG. 9 .

Experimental Example 7: Analysis of surface contact angle and permeability of polymer membrane to water

Polymer films of Comparative Examples 7 and 6 to 8 were formed in the same manner as in Table 4 and Example 2 using the amphiphilic cross-linked copolymer prepared in Example 1. For each polymer membrane, surface contact angle and permeability analysis for water were performed to confirm the surface hydrophilicity and water permeability of the membrane, and the results are shown in Table 4 and FIGS. 11 and 12 .

The surface hydrophilicity of the membrane is one of the most important properties affecting the permeation performance. The hydrophilicity of a membrane is usually measured by dropping water on the surface of the membrane and checking the contact angle with water. The low contact angle means that the surface of the membrane is hydrophilic.

11 shows the results of measuring the surface contact angle with respect to water for the polymer membranes prepared in Examples 6 to 8 (b, c, d) and Comparative Example 7 (a).

division P(VDF- co -CTFE)(x), g P(VDF- co -CTFE):P2VP(5:5)(y), g weight ratio
(x:y) non-solvent good solvent CA (ㅀ) Comparative Example 7 (M7) 0.75 - 1:0
D.I. Water NMP 88.0 Example 6 (M8) 0.675 0.075 9:1 NMP 87.3 Example 7 (M9) 0.6 0.15 8:2 NMP 80.8 Example 8 (M10) 0.525 0.225 7:3 NMP 78.4

Table 3 and FIG. 11 show the results of the composition of the polymer solution and the contact angle, and the contact angles of the polymer films were measured to be 88.0 ^o , 87.3 ^o , 80.8 ^o and 78.4 ^o , respectively. In particular, the contact angle decreased as the amount of the P(VDF- co -CTFE) -g -P2VP copolymer increased from Example 6 (M8) to Example 8 (M10), which indicates that the ratio of P2VP was This is because the hydrophilicity and porosity increased with the increase. As a result, it was found that the P2VP side chain plays a significant role in enhancing the hydrophilicity of the membrane surface.

12 is a graph showing the results of measuring pure water permeability over time for the polymer membranes prepared in Examples 6 to 8 (M8, M9, M10) and Comparative Example 7 (M7). 12, the pure water permeability is affected by various properties of the membrane, such as pore size, porosity, cross-sectional structure, and hydrophilicity. Examples 6 to 8 (M8, M9, M10) and Comparative Example 7 (M7) ) of the polymer membranes, the water permeability increased from 57.2 L/m ² oh bar to 310.1 L/m ² oh bar after 60 minutes (min), which is the pure P(VDF-) of Comparative Example 7 (M7). co -CTFE) has a transmittance that is 5.4 times higher than that of a polymer membrane. The increase in water permeability is due to the development of a well-ordered pore structure with a large number of macropores due to the interaction between the P2VP side chain and the NMP solvent, as demonstrated by the aforementioned TEM, SEM, FT-IR, XRD, and SAXS analysis. will be. In addition, the introduction of the P2VP chain increased the hydrophilicity of the membrane surface, and as the amount of P(VDF- co -CTFE) -g -P2VP copolymer increased, the water permeability also increased.

Experimental Example 8: N of polymer membrane ₂ Gas Permeability Analysis

In order to evaluate the applicability of the polymer membranes prepared in Example 4 and Comparative Examples 2 to 4 as a gas separation membrane, a single N ₂ gas permeability analysis of the membrane was performed at 25 ° C. The results are shown in Table 5.

According to the results in Table 5, Comparative Examples 2 (M1) and Example 4 (M3) prepared using an NMP solvent were prepared using a DMF solvent in Comparative Examples 3 (M2) and Comparative Example 4 (M4). ) , it can be seen that the gas permeability is significantly higher than that of the membrane. As can be seen in FIGS. 4 and 5, M1 and M3 have a finger-like structure with more pores and macropores on the surface, so this structure facilitates the transport of gas molecules.

On the other hand, in the case of Comparative Example 3 (M2) and Comparative Example 4 (M4), it was found that the gas permeability was remarkably low as the porosity was low and a sponge-like structure was observed. Through this, as mentioned above, the use of the NMP solvent causes immediate de-mixing in the polymer matrix, resulting in a well-ordered and well-pore-formed structure.

In particular, in the case of Example 4 (M3), the N ₂ gas permeability is 6.2 x 10 ⁴ GPU (1 GPU = 10 ^-6 cm ³ [STP] / [s cm ² cmHg]) commercial polyethersulfone (polyethersulfone) and polysulfone support showed comparable values. This shows that the P(VDF- co -CTFE) -g -P2VP copolymer has higher thermal and chemical stability than the P(VDF- co -CTFE) polymer of Comparative Examples 2 (M1) and Comparative Examples 3 (M2). , and N ₂ gas permeability is also excellent, so it can be seen that it is a promising material for application as a polymer membrane for gas separation membranes.

Claims (27)

A polymer membrane comprising an amphiphilic branched copolymer in which a hydrophilic polymer side chain is copolymerized by atom transfer radical polymerization to a side branch of a hydrophobic polymer main chain,
As a result of XRD analysis of the polymer film, the polymer film, characterized in that 2θ shows a fourth effective peak and a fifth effective peak in the range of ④ 26° to 27° and ⑤ in the range of 38° to 39°, respectively.
The method of claim 1,
The hydrophobic polymer is polyvinylidene fluoride-co-chlorotrifluoroethylene (Poly (vinylidenefluoride-co-chlorotrifluoroethylene), P (VDF-co-CTFE)) of the polymer membrane.
According to claim 1,
The hydrophilic polymer is a polymer membrane that is 2-vinylpyridine (2-vinylpyridine), 4-vinylpyridine (4-vinylpyridine) or a mixture thereof.
According to claim 1,
The amphiphilic branched copolymer is a polymer membrane wherein the hydrophobic polymer main chain and the hydrophilic polymer side chain are polymerized in a weight ratio of 5:5 to 7:3.
The method of claim 1,
The amphiphilic branched copolymer has a number average molecular weight (Mn) of 125,000 to 200,000 g/mol, and a molecular weight distribution (PDI) of 1.5 to 3.
The method of claim 1,
The amphiphilic branched copolymer is a polymer membrane that is a compound represented by the following formula (1).
[Formula 1]

(In Formula 1,
R ₁ To R ₄ Are the same as or different from each other, and each independently H, Cl,

and an alkyl group having 1 to 20 carbon atoms;
x, y and z are 100: 10-15: 20-80 as a polymerization molar ratio of each repeating unit,
y' is an integer from 0 to 10.)
7. The method of claim 6,
In Formula 1,
R ₁ and R ₂ are different from each other, and each independently H, Cl and

is selected from
R ₃ and R ₄ are the same as each other and are each independently H;
x, y and z are 100: 12-14: 26-60 as a polymerization molar ratio of each repeating unit,
y' is an integer from 0 to 1, the polymer membrane.
According to claim 1,
The amphiphilic branched copolymer is a polymer film having a peak corresponding to the CF bond in the wavelength range of 1185 to 1205 cm ^-1 as a result of FT-IR analysis.
According to claim 1,
As a result of XRD analysis, the polymer film has a first effective peak, a second effective peak and a third effective peak in the range of ① 17 ° to 18 °, ② 18.2 ° to 19 °, and ③ 20 ° to 21 °, respectively, as a result of XRD analysis. A polymer film that is visible.
10. The method of claim 9,
an intensity ratio of (first effective peak)/(second effective peak) is 0.9 to 1.1, and an intensity ratio of (second effective peak)/(third effective peak) is 0.5 to 0.8, wherein The intensity ratio of (third effective peak)/(fourth effective peak) is 4.1 to 5.5, and the intensity ratio of (fourth effective peak)/(fifth effective peak) is 0.9 to 1.3.
The method of claim 1,
The polymer film is a polymer film having a thickness of 30 to 200 μm.
According to claim 1,
The polymer membrane is a polymer membrane for a gas separation membrane, for a water treatment membrane, for an ionic electrolyte membrane, or for an ion exchange membrane.
A gas separation membrane comprising the polymer membrane according to any one of claims 1 to 12.
14. The method of claim 13,
The gas separation membrane is a gas separation membrane that separates one or more gases selected from carbon dioxide, nitrogen, and methane.
14. The method of claim 13,
The gas separation membrane is a gas separation membrane that has a nitrogen (N ₂ ) permeability of 3 x 10 ⁴ to 8 x 10 ⁴ GPU.
A gas separation device comprising the gas separation membrane of claim 13 .
A gas collection device comprising the gas separation membrane of claim 13 .
preparing an amphiphilic branched copolymer by adding a hydrophobic polymer, a hydrophilic polymer, a catalyst, and a polymerization initiator to a first organic solvent and copolymerizing by atom transfer radical polymerization;
preparing a polymer casting solution by dissolving a fluorine-based polymer and the amphiphilic branched copolymer in a second organic solvent; and
preparing a polymer film by a non-solvent-induced phase separation method after applying the polymer casting solution to a substrate;
A method for producing a polymer membrane comprising a.
19. The method of claim 18,
The first organic solvent is N-methyl-2-pyrrolidinone (N-Methyl-2-pyrrolidinone, NMP), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), dimethylformamide (DMF) and tetrahydro A method for producing a polymer membrane that is at least one selected from the group consisting of furan (THF).
19. The method of claim 18,
The step of preparing the amphiphilic branched copolymer is a method for producing a polymer membrane by polymerizing the hydrophobic polymer and the hydrophilic polymer in a weight ratio of 5:5 to 7:3.
19. The method of claim 18,
The catalyst is CuCl, CuCl ₂ , CuBr and CuBr ₂ The method for producing a polymer membrane is at least one selected from the group consisting of.
19. The method of claim 18,
The polymerization initiator is 1,1,4,7,10,10-hexamethylenetriethylenetetramine (1,1,4,7,10,10-Hexamethyltriethylenetetramine, HMTETA), N,N,N',N', N''-pentamethyl diethylenetriamine (N,N,N',N', N''-pentamethyl diethylenetriamine, PMDETA), 4,4'-dimethyl-2,2'-dipyridyl (4,4 '-dimethyl-2,2'-dipyridyl, DMDP), tris(2-aminoethyl)amine (TRE), tris(2-dimethylaminoethyl)amine (tris(2-dimethylaminoethyl) amine, Me6-TREN), 2,2'-Bipy (Bipyridine), N,N,N',N-tetramethylethylenediamine (N,N,N', N-Tetramethylethylenediamine, TMEDA) and 1,4,8,11-tetraazacyclotetradecane (1,4,8,11-tetraazacyclotetradecane, Me4-Cyclam) at least one selected from the group consisting of a method for producing a polymer membrane.
19. The method of claim 18,
The step of preparing the amphiphilic branched copolymer is a method for producing a polymer membrane by atom transfer radical polymerization at 70 to 110° C. for 10 to 30 hours.
19. The method of claim 18,
The second organic solvent is N-methyl-2-pyrrolidone (N-Methyl-2-pyrrolidinone, NMP) is a method for producing a polymer membrane.
19. The method of claim 18,
The fluorine-based polymer is poly(vinylidene fluoride-co-chlorotrifluoroethylene) (poly(vinylidene fluoride-co-chlorotrifluoroethylene, P(VDF- co -CTFE)).
19. The method of claim 18,
The polymer casting solution is a method for producing a polymer membrane by mixing the fluorine-based polymer and the amphiphilic branched copolymer in a weight ratio of 9.5:0.5 to 6:4.
19. The method of claim 18,
The first organic solvent is N-methyl-2-pyrrolidone (N-Methyl-2-pyrrolidinone, NMP),
The hydrophobic polymer is polyvinylidenefluoride-co-chlorotrifluoroethylene (Poly (vinylidenefluoride-co-chlorotrifluoroethylene), P (VDF-co-CTFE)),
The hydrophilic polymer is 2-vinylpyridine (2-vinylpyridine),
The step of preparing the amphiphilic branched copolymer is to polymerize the hydrophobic polymer and the hydrophilic polymer in a weight ratio of 6:4 to 5:5,
The catalyst is CuCl,
The polymerization initiator is 1,1,4,7,10,10-hexamethylenetriethylenetetramine (1,1,4,7,10,10-Hexamethyltriethylenetetramine, HMTETA),
The step of preparing the amphiphilic branched copolymer is to conduct atom transfer radical polymerization at 80 to 100° C. for 18 to 22 hours,
The second organic solvent is N-methyl-2-pyrrolidone (N-Methyl-2-pyrrolidinone, NMP),
The fluorine-based polymer is poly(vinylidene fluoride-co-chlorotrifluoroethylene) (poly(vinylidene fluoride-co-chlorotrifluoroethylene, P(VDF- co -CTFE)),
The polymer casting solution is a method for producing a polymer membrane by mixing the fluorine-based polymer and the amphiphilic branched copolymer in a weight ratio of 9:1 to 8:2.

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