KR102161977B1 - A gas separation membrane comprising an amine compound - Google Patents

Abstract

An embodiment of the present invention is a matrix comprising polyethylene oxide; And an amine-based compound dispersed in the matrix.

Description

A gas separation membrane containing an amine compound {A GAS SEPARATION MEMBRANE COMPRISING AN AMINE COMPOUND}

The present invention relates to a gas separation membrane comprising a matrix comprising polyethylene oxide and an amine-based compound dispersed in the matrix.

Among the many efforts to reduce greenhouse gas emissions, carbon dioxide reduction technology is receiving great attention to overcome global warming and global climate change. Carbon dioxide, which accounts for more than 80% of various greenhouse gases, is mainly generated from fossil fuel combustion and petrochemical plants. Therefore, the technology for separating carbon dioxide from the combustion gas is emerging as an important field. Gas separation membrane technology is believed to replace existing separation technologies such as absorption, distillation, and chemical adsorption due to its low manufacturing cost, low operating cost, and environmentally friendly properties.

In particular, a number of research results have been reported that polymer membranes have high gas permeability and selectivity. However, there is a problem in that the gas permeability and selectivity of a general polymer membrane are in a trade-off relationship. Therefore, new types of separators that solve this problem are being studied. Among them, mixed matrix membranes (MMMs) are composed of a polymer matrix and a porous filler, and have higher permeability than conventional polymer membranes. It has been reported as possible.

However, despite these advantages, there are some problems with the mixed medium separation membrane. A typical problem is that there is a limitation in obtaining high selectivity due to the formation of interfacial voids without selectivity due to low compatibility between the organic polymer matrix and the filler. To solve this problem, a new type of separator is needed.

Poly(ethylene oxide) (PEO)) is emerging as a raw material for next-generation gas separation membranes as it can have high carbon dioxide solubility by interacting with carbon dioxide gas molecules and Lewis acid-bases by oxygen molecules in the ether group. However, when the polyethylene oxide is formed and used as a gas separation membrane, there is a problem in that a structural defect occurs due to the strong crystallization tendency of the polyethylene oxide. Poly(oxyethylene methacrylate), which is a polyethylene oxide-based polymer, has amorphous properties, but has a problem that it is difficult to apply as a gas separation membrane due to poor mechanical strength. Therefore, it is extremely rare to apply a gas separation membrane using pure polyethylene oxide.

Dendrimer is a type of repetitively branched polymer with a cascade topology. Poly(amidoamine) (PAMAM) was first reported in 1985 by Tomalia's team, and star-shaped polyamidoamine dendrimers have a high density of amine functional groups. Therefore, it has a large number of active points, and due to these characteristics, it has been applied in various fields in the bio field or optical sensor field.

D.A. Tomalia, H. Baker, J. Dewald, M. Hall, G. Kallos, S. Martin, J. Roeck, J. Ryder, P. Smith, Dendritic macromolecules: synthesis of starburst dendrimers, Macromolecules, 19 (1986) 2466- 2468. F. Zhang, B. Wang, S. He, R. Man, Preparation of graphene-oxide/polyamidoamine dendrimers and their adsorption properties toward some heavy metal ions, Journal of Chemical & Engineering Data, 59 (2014) 1719-1726.

The present invention is to solve the problems of the prior art described above, the object of the present invention is to solve the problem of conventional interface defects by introducing an amine compound into a polyethylene oxide matrix, and to provide a gas separation membrane having high carbon dioxide selectivity. will be.

One aspect of the present invention is a matrix comprising polyethylene oxide; And an amine-based compound dispersed in the matrix.

In one embodiment, the weight average molecular weight (M _w ) of the polyethylene oxide may be 100,000 to 5,000,000 g/mol.

In one embodiment, the weight average molecular weight (M _w ) of the polyethylene oxide may be 500,000 to 1,500,000 g/mol.

In one embodiment, the amine-based compound may have a polyamidoamine dendrimer structure.

In one embodiment, the content of the amine compound may be 2.5 to 20% by weight based on the total weight of the gas separation membrane.

In one embodiment, the content of the amine-based compound may be 7.5 to 15% by weight based on the total weight of the gas separation membrane.

In one embodiment, the gas separation membrane may have a permeability of 10 to 35 barrer for carbon dioxide.

In one embodiment, the gas separation membrane may have a permeability of 0.2 to 5 barrer to nitrogen.

In one embodiment, the gas separation membrane may be a gas separation membrane having a selectivity of 40 to 60 carbon dioxide relative to nitrogen.

According to an aspect of the present invention, a gas separation membrane having excellent gas separation performance may be provided by dispersing an amine-based compound in a matrix including polyethylene oxide having strong crystallinity to suppress the occurrence of interfacial defects.

The gas separation membrane may have a high carbon dioxide permeability, a high carbon dioxide/nitrogen selectivity, and a low polyethylene oxide crystallization rate compared to a conventional gas separation membrane by effectively filling the pores of the polyethylene oxide by interacting with the amine compound and polyethylene oxide.

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

1 is a photograph of a polyethylene oxide/polyamidoamine gas separation membrane having different contents of a polyethylene oxide matrix and polyamidoamine prepared according to an embodiment of the present invention.
Figure 2 is methyl acrylate (MA), tris (2-aminoethyl) amine (tris (2-aminoethyl) amine, TAEA), polyamidoamine 0.5 G, ethylene diamine (EDA) and polyamido. It shows the results of Fourier Transform Infrared analysis (FT-IR) of the amine dendrimer.
3 is an FT-IR result of a polyethylene oxide matrix, a polyamidoamine dendrimer, and a polyethylene oxide/polyamidoamine separator.
FIG. 4 is an X-ray diffraction (XRD) analysis of a polyethylene oxide/polyamidoamine separator having different contents of a polyethylene oxide matrix, polyamidoamine dendrimer, and polyamidoamine.
5 is an X-ray small-angle X-ray scattering (SAXS) analysis of a polyethylene oxide/polyamidoamine separation membrane having different polyethylene oxide matrix and polyamidoamine content.
6 is a differential scanning calorimeter (DSC) of a polyethylene oxide/polyamidoamine separator having different contents of polyethylene oxide matrix, polyamidoamine dendrimer, and polyamidoamine.
FIG. 7 shows the results of analyzing a stress-strain curve of a polyethylene oxide/polyamidoamine separator having different contents of a polyethylene oxide matrix and polyamidoamine.
8 is a view showing permeability to carbon dioxide and selectivity of carbon dioxide versus nitrogen of a polyethylene oxide/polyamidoamine separator having different contents of a polyethylene oxide matrix and polyamidoamine.
9 is a carbon dioxide solubility and diffusivity of a polyethylene oxide separator and a polyethylene oxide/polyamidoamine separator having different amounts of polyamidoamine measured using a permeation membrane analyzer (PMA).

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be implemented in various different forms, and therefore is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only "directly connected" but also "indirectly connected" with another member interposed therebetween. . In addition, when a part "includes" a certain component, it means that other components may be further provided, rather than excluding other components unless specifically stated to the contrary.

When a range of numerical values is presented herein, the value has the precision of the significant digits provided according to the standard rules in chemistry for significant digits, unless a specific range thereof is stated otherwise. For example, 10 includes a range of 5.0 to 14.9, and the number 10.0 includes a range of 9.50 to 10.49.

In the present specification, conditions such as temperature and atmospheric pressure in each process may be performed at standard temperature and pressure (STP) unless otherwise specified.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Gas separation membrane

A gas separation membrane according to an aspect of the present invention includes a matrix comprising polyethylene oxide; And an amine-based compound dispersed in the matrix.

The gas separation membrane may be a porous matrix capable of permeating gas, and each pore may have a high carbon dioxide solubility.

Polyethylene oxide is a polymer produced by ring-opening polymerization of ethylene oxide, and has the same general formula as polyethylene glycol, but in general, polyethylene glycol is a weight average molecular weight mainly used in the bio field. This means a low molecular weight oligomer of less than 20,000 g/mol, and polyethylene oxide means a polymer having a weight average molecular weight of 20,000 g/mol or more.

Depending on the effect of the chain length, polyethylene oxide and polyethylene glycol have different mechanical properties, and in particular, since the weight average molecular weight exhibits crystallinity at 1,000 g/mol or more, polyethylene oxide may have stronger crystallinity than polyethylene glycol.

The weight average molecular weight (M _w ) of the polyethylene oxide may be 100,000 to 5,000,000 g/mol, or 500,000 to 1,500,000 g/mol, but is not limited thereto. If the weight average molecular weight of the polyethylene oxide is less than 100,000, it may be difficult to form a film with a separator, and if it exceeds 5,000,000, the melt viscosity rapidly increases, resulting in a problem of deteriorating processability.

The weight average molecular weight of polyethylene oxide can be measured using gel permeation chromatography (GPC). For example, after preparing a sample sample of a certain concentration, the GPC measuring device is stabilized, and when the device is stabilized, a standard sample and a sample sample are injected into the device to obtain a chromatogram, and then the weight average molecular weight can be calculated.

The amine compound may be an amine compound having a repeating branched structure, and may interact with the matrix and carbon dioxide by including a branched structure including an amine or amide functional group.

The amine-based compound may be a polyamidoamine dendrimer, but is not limited thereto.

The content of the amine compound may be 2.5 to 20% by weight based on the total weight of the gas separation membrane, or 7.5 to 15% by weight based on the total weight of the gas separation membrane, but is not limited thereto. By controlling the content of the amine compound, crystallinity of the matrix may be controlled, or carbon dioxide permeability or selectivity may be improved. A typical mixed medium separation membrane has a problem in that the selectivity of carbon dioxide decreases due to the formation of interfacial voids without selectivity, but according to an aspect of the present invention, carbon dioxide of the gas separation membrane is filled by dispersing the amine compound in the matrix to fill the void The selectivity for can be improved.

The gas separation membrane may have a carbon dioxide permeability of 10 to 35 barrer or a carbon dioxide selectivity to nitrogen of 40 to 60. The gas separation membrane may satisfy the permeability and selectivity conditions, respectively, but preferably, the gas separation membrane may simultaneously satisfy the conditions.

The permeability unit, barrer, means 10 ^-10 cm ³ ·cm/cm ² ·s ·cmHg, and represents the gas permeability of a material in a bulk state.

Method of manufacturing gas separation membrane

A method of manufacturing a gas separation membrane according to another aspect of the present invention includes the steps of: (a) preparing an amine-based compound; (b) dispersing the amine compound in a matrix including polyethylene oxide to prepare a gas separation membrane including the amine compound and polyethylene oxide; may include.

The step (a) may be a Michael addition polymerization using MA and EDA centering on TAEA, but is not limited thereto.

Hereinafter, embodiments of the present invention will be described in more detail. However, the following experimental results are only representative of the above examples, and cannot be interpreted as the scope and content of the present invention are reduced or limited by examples. Effects of each of the various embodiments of the present invention not explicitly presented below will be specifically described in the corresponding section.

According to the following examples and experimental examples according to an aspect of the present invention, a gas separation membrane having high carbon dioxide selectivity and no defects can be manufactured. The gas separation membrane is composed of a polyethylene oxide polymer matrix and an amine-branched polyamidoamine additive. The polyamidoamine dendrimer was prepared by two-step addition polymerization consisting of a Michael addition polymerization and amidation process represented by the following Scheme 1.

[Scheme 1]

The rich amine functional group of the prepared polyamido can promote the permeation of carbon dioxide through a reversible reaction with carbon dioxide molecules. When the polyamidoamine dendrimer is introduced into the polyethylene oxide polymer matrix, the polyamidoamine having a small size can be hydrogen-bonded with the ethylene oxide group of the polyethylene oxide to effectively block the gap between the large polyethylene oxide crystals. In the case of the polyethylene oxide membrane into which the polyamidoamine was introduced, the carbon dioxide/nitrogen selectivity was significantly improved compared to the pure polyethylene oxide membrane.

Sample or experimental tool

Name of sample or experiment manufacturer Remark tris(2-aminoethyl)amine (TAEA) Sigma-aldrich - methyl acrylate (MA) Sigma-aldrich - ethylenediamine (EDA) Sigma-aldrich - poly(ethylene oxide) PEO Sigma-aldrich M _w : 1,000,000 gmol ^-1 Methanol and ethanol J. T. Baker - DSC Perkin Elmer, DSC8000 Measurement of temperature rise at 10℃ per minute in a nitrogen environment XRD RIGAKU, RINT 2000 - SAXS Pohang Light Source (PLS), 4C SAXS II beamline - Thermal stability measurement (thermogravimetric analysis, TGA) TA instruments, DTA/TGA analyzer - Mechanical strength measurement Universal testing machine (UTM) - Gas permeation performance measurement Airrane, time-lag - FT-IR DIGLAS Co. Hannover, Excalibur series -

Manufacturing example

2.5 g of TAEA was dissolved in 10 mL of methanol to prepare a TAEA solution, and 19.6 mL of MA was dissolved in 20 mL of methanol to prepare a MA solution. After each of the TAEA and MA solutions was stirred for 30 minutes, a reaction mixture was prepared by adding the MA solution dropwise to the TAEA solution under a nitrogen condition of -20 ^° C. The reaction mixture was reacted at room temperature for 24 hours and then dried by distillation under reduced pressure at 50 ^o C to prepare 0.5 G of PAMAM. 19.8 g of EDA and 5 g of PAMAM 0.5 G prepared above were each dispersed in 10 mL of methanol. For the two dispersed solutions, a polyamidoamine dendrimer was prepared by repeating the same process of preparing 0.5 G of polyamidoamine mentioned above.

Example 1

Polyethylene oxide having a weight average molecular weight (M _w ) of 1,000,000 was dissolved in ethanol at 50 ^o C to prepare a polyethylene oxide solution. A mixed solution was prepared by adding 2.5% by weight of polyamidoamine dendrimer to the polyethylene oxide solution based on the total weight of the solution. After evaporating the mixed solution, the mixture was first dried at room temperature for 6 hours and secondarily dried at 50 ^o C to prepare a polyethylene oxide/polyamidoamine gas separation membrane.

Example 2

A polyethylene oxide/polyamidoamine gas separation membrane was prepared in the same manner as in Example 1, except that 5% by weight of the polyamidoamine dendrimer was added to the total solution weight.

Example 3

A polyethylene oxide/polyamidoamine gas separation membrane was prepared in the same manner as in Example 1, except that 10% by weight of the polyamidoamine dendrimer was added to the total solution weight.

Example 4

A polyethylene oxide/polyamidoamine gas separation membrane was prepared in the same manner as in Example 1, except that 20% by weight of the polyamidoamine dendrimer was added to the total solution weight.

Comparative Example 1

A gas separation membrane was prepared in the same manner as in Example 1, except that a gas separation membrane was prepared using only polyethylene oxide without adding a polyamidoamine dendrimer.

Experimental Example 1

FIG. 2 is an FT-IR photograph of methyl acrylate, tris(2-aminoethyl)amine, polyamidoamine, ethylenediamine, and polyamidoamine dendrimer.

Tris(2-aminoethyl)amine, which constitutes the core core of the polyamidoamine dendrimer, has a 1,592 cm ^-1 band by the stretching mode of the amine functional group and a 3,300 cm ^-1 band by the vibration mode. have. The methyl acrylate constituting the branch of the polyamidoamine dendrimer is a strong 1,726 cm ^-1 by C=O functional group. It has a nearby band. In the case of 0.5 G of polyamidoamine synthesized from tris(2-aminoethyl)amine and methylacrylate, the amine functional group of tris(2-aminoethyl)amine through the disappearance of the 1,592 cm ^-1 band and 3,300 cm ^-1 band It was confirmed that the C=C double bond of methyl acrylate disappeared due to the reaction, 1,726 cm ^-1 Nearby band is 1,731 cm ^-1 Through the movement to the vicinity, it was confirmed that the strength of the C=O functional group became stronger as the distance between the C=O functional groups increased due to Michael addition polymerization.

Polyamidoamine dendrimers synthesized from polyamidoamine and ethylenediamine have bands around 1,550 cm ^-1 and 1,642 cm ^-1 due to the bonding of C=O, NH and CH stretching modes. In conclusion, it can be seen from FIG. 2 that the polyamidoamine dendrimer was successfully synthesized.

Experimental Example 2

3 is an FT-IR analysis photograph of a polyethylene oxide matrix, a polyethylene oxide/polyamidoamine gas separation membrane, and a polyamidoamine.

The polyethylene oxide matrix has 1,094 cm ^-1 bands by COC stretching mode and 2,877 cm ^-1 bands by CH symmetric stretching mode, and polyamidoamine is 1,643 cm ^- by stretching mode of C=O functional groups. ^It has ¹ strip.

In the polyethylene oxide/polyamidoamine gas separation membrane, the 1,094 cm ^-1 band by the COC functional group and the 2,877 cm ^-1 band by CH did not move, but the 1,643 cm ^-1 band by the C=O functional group was 1,638 cm Moved to ^-1 and confirmed that the wave number was lowered. In general, when a C=O functional group interacts with another functional group, its wave number decreases.Thus, CH and COC in the polyethylene oxide/polyamidoamine gas separation membrane do not change, but C=O functional groups with other functional groups By interaction, it can be seen that the polyethylene oxide matrix and polyamidoamine are well mixed.

Experimental Example 3

4 shows XRD patterns of polyethylene oxide/polyamidoamine gas separation membranes with different concentrations of polyethylene oxide matrix, polyamidoamine, and polyamidoamine.

The polyethylene oxide matrix showed sharp crystalline peaks at 19.2 ^o and 23.4 ^o . When using Bragg's law, the d-spacing between domains was calculated to be 4.6 Å and 3.8 Å, respectively. The crystalline peak of this polyethylene oxide matrix is due to the strong hydrogen bonding between the aligned polyether branch and the polyethylene oxide. On the other hand, polyamidoamine showed a broad peak at 21.1 ^o , and a crystalline peak such as a polyethylene oxide matrix was not observed.

As the amount of polyamidoamine added was increased, the intensity of the crystalline peak of the polyethylene oxide/polyamidoamine gas separation membrane gradually decreased. Through this, it can be seen that the interaction between the polyamidoamine and the polyethylene oxide matrix interferes with the chain-packing of the polyethylene oxide matrix.

Experimental Example 4

Polyamidoamine content
(weight%) Peak 1
(nm ^-1 ) Peak 2
(nm ^-1 ) q/q _max ratio d-spacing
(nm) 0 0.1153 0.2259 1:2 54.5/27.8 2.5 0.0982 0.1948 1:2 64.0/32.2 5 0.0919 0.187 1:2 68.4/33.6 10 0.1044 - - 60.2 20 0.1075 - - 58.4

5 and Table 2 are SAXS analysis results of polyethylene oxide/polyamidoamine separation membranes having different concentrations of polyethylene oxide matrix and polyamidoamine.

The polyethylene oxide matrix was narrow and strong and showed two peaks with a q/q _max -ratio of 1:2. In addition, it had a lamellar structure, which was attributed to the fact that long polyethylene oxide chains are arranged at a certain distance from nearby molecules due to the high molecular weight of polyethylene oxide. When using the Bragg equation, the d-spacing of polyethylene oxide was calculated as 54.5 nm.

As the content of polyamidoamine increased, the intensity and position of the peaks changed, but the polyethylene oxide/polyamidoamine gas separation membrane still maintained the lamellar structure. The d-spacing increased until the content was 5% by weight. This means that the amount of the amorphous portion of the polyethylene oxide and the distance between the crystalline region are increased. That is, as polyamidoamine capable of strong interaction is introduced, polyamidoamine interferes with the process of crystallization of polyethylene oxide, thereby reducing the crystallinity of the separator. The radius of gyration (R _g ) of polyamidoamine has been reported to be about 7.5 Å, and polyamidoamine having a small size can be effectively introduced between crystalline regions to fill defects at the interface. Therefore, it can be interpreted that d-spacing increases as the amount of added polyamidoamine increases. When the content was 10% by weight or more, the polyamidoamine greatly prevented the polyethylene oxide chains from forming the lamellar crystal structure, and thus the lamellar crystal peak on the SAXS curve disappeared.

Experimental Example 5

Polyamidoamine content
(weight%) T _m ^PEO ( ^o C) X _c ^PEO 0 66.4 50.8 2.5 66.6 49.6 5 66.5 48.0 10 66.0 44.0 20 66.0 39.8

6 and Table 3 are DSC analysis results of polyethylene oxide/polyamidoamine separators having different concentrations of polyethylene oxide matrix and polyamidoamine.

The polyethylene oxide matrix exhibited a melting temperature (T _m ) at 66.4 ^o C due to its high crystallinity. As polyamidoamine was added, the melting point hardly changed, but the intensity of the peak gradually decreased.

The degree of crystallinity (X _c ) calculated by the following equation was used to confirm the quantitative value of the structural properties.

X _c (%) = ΔH _f /ΔH _{f(100% crystal)} x 100

ΔH _f is the heat of fusion calculated from the melting point area of the DSC curve, and ΔH _{f (100% crystal)} is the heat of fusion of the 100% crystallized polymer. The ΔH _{f (100% crystal)} of polyethylene oxide is known to be 205 J/g. As previously confirmed in XRD analysis and SAXS analysis, the crystallinity of the polyethylene oxide/polyamidoamine gas separation membrane steadily decreased as the amount of added polyamidoamine increased.

Experimental Example 6

7 is a result of UTM analysis of a polyethylene oxide/polyamidoamine separator having different concentrations of a polyethylene oxide matrix and polyamidoamine.

All membranes exhibited the shape of a typical semi-crystalline polymer strain curve. Although the introduction of polyamidoamine did not change the shape of the curve, strain and stress increased steadily as the amount of polyamidoamine increased.

In general, as the crystallinity of the polymer increases, the mechanical strength increases. In the case of the polyethylene oxide/polyamidoamine gas separation membrane, as the content of polyamidoamine increased, the mechanical strength increased. This is because the small sized polyamidoamine effectively fills the large polyethylene oxide crystals, as if the adhesive It can be understood as lowering the crystallinity of the separator by performing a role.

Experimental Example 7

Polyamidoamine content
(weight%) thickness
(㎛) Transmittance (Barrer) Selectivity
(CO ₂ /N ₂ ) CO ₂ N ₂ 0 (pure PEO) 60 2388 2589 0.92 0 57 34.2 4.56 7.5 2.5 52 32.3 0.77 42 5 60 25.8 0.6 43 10 75 25.5 0.45 56.7 20 55 10.1 0.42 24.0

8 and Table 4 are the results of measuring the gas separation characteristics of the polyethylene oxide matrix and the polyethylene oxide / polyamidoamine separation membrane having different concentrations of polyamidoamine in a time-lag method at 35 ^o C, 1 bar.

In the case of pure PEO, a polyethylene oxide separator that was only dried at room temperature without additional heat treatment, and exhibited a very low selectivity of 0.92 due to structural defects. The polyethylene oxide membrane after 6 hours of heat treatment showed a relatively increased gas selectivity of 7.5 compared to pure PEO by preventing large defects. However, still showing a gas selectivity of less than 10 is due to the interface defects between the polyethylene oxide crystals.

As the content of polyamidoamine increased, both carbon dioxide and nitrogen permeability decreased. The decrease in permeability to nitrogen is due to the filling effect of the polyamidoamine. The primary amine functional group of polyamidoamines interacts with polyethylene oxide chains to help fill non-selective voids. The reason that the permeability to carbon dioxide is slightly reduced compared to the large decrease in nitrogen permeability is because the primary amine of the polyamidoamine and the carbon dioxide molecule have strong affinity.

The numerical value also increases and has a maximum value when it is 10% by weight, and then decreases. This tendency is because excess polyamidoamine acts as a barrier to gas permeation by hydrogen bonding with the polyethylene oxide matrix.

Experimental Example 8

Polyamidoamine content
(weight%) CO ₂ solubility
(Х10 ^-1 ) CO ₂ diffusivity
(Х10 ^-9 ) CO ₂ transmittance
(Barrer) 0 3.01 11.35 34.2 2.5 4.03 8.02 32.3 5 3.38 7.64 25.8 10 3.73 6.83 25.5 20 3.29 3.09 10.1 (Unit: solubility = cm ³ (STP) cm ^-3 cmHg ^-1 , diffusivity = cm ² s ^-1 )

9 and 5 are PMA measurement results of polyethylene oxide/polyamidoamine separators having different concentrations of polyethylene oxide matrix and polyamidoamine. In addition, the permeability to carbon dioxide was obtained by multiplying the measured solubility and diffusivity.

The solubility of the polyethylene oxide/polyamidoamine gas separation membrane in carbon dioxide was higher than that of the pure polyethylene oxide matrix. This is because the primary amine functional group of polyamidoamine is effective in improving the solubility of carbon dioxide.

Although the crystallinity of the polyethylene oxide matrix decreased as the polyamidoamine content increased, the diffusivity and permeability of the polyethylene oxide/polyamidoamine gas separation membrane to carbon dioxide decreased. The tendency to decrease in permeability is because permeability is dominated by diffusivity rather than solubility.

The above description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as being distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims to be described later, and all changes or modified forms derived from the meaning and scope of the claims and the concept of equivalents thereof should be construed as being included in the scope of the present invention.

Claims (9)

A matrix comprising polyethylene oxide; And
Including; polyamidoamine dendrimer dispersed in the interior of the matrix,
The content of the polyamidoamine dendrimer is 2.5 to 15% by weight based on the total weight of the gas separation membrane, gas separation membrane. The method of claim 1,
The weight average molecular weight (M _w ) of the polyethylene oxide is 100,000 to 5,000,000 g/mol, gas separation membrane. The method of claim 2,
The weight average molecular weight (M _w ) of the polyethylene oxide is 500,000 to 1,500,000 g/mol, gas separation membrane. delete delete The method of claim 1,
The content of the polyamidoamine dendrimer is 7.5 to 15% by weight based on the total weight of the gas separation membrane, gas separation membrane. The method of claim 1,
The gas separation membrane has a permeability of 10 to 35 barrer for carbon dioxide. The method of claim 1,
The gas separation membrane has a permeability of 0.2 to 5 barrer to nitrogen. The method of claim 1,
The gas separation membrane has a selectivity of carbon dioxide to nitrogen of 40 to 60.

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