KR100308525B1 - Perfluoroalkyl group-containing polymers for separation membranes - Google Patents

Abstract

The present invention relates to a perfluoroalkyl-containing polymer separation membrane, and more particularly, gas separation, pervaporation, ultrafiltration prepared using a perfluorinated alkyl-containing polymer obtained by polymerizing a perfluoroalkyl-containing diamine and a dicarboxylic acid derivative. The present invention relates to a polymer separation membrane exhibiting excellent separation performance by being applied to general membrane separation processes such as microfiltration, reverse filtration, and the like.

Description

Perfluoroalkyl group-containing polymers for separation membranes

The present invention relates to a perfluoroalkyl-containing polymer separation membrane, and more particularly, gas separation, pervaporation, ultrafiltration prepared using a perfluorinated alkyl-containing polymer obtained by polymerizing a perfluoroalkyl-containing diamine and a dicarboxylic acid derivative. The present invention relates to a polymer separation membrane exhibiting excellent separation performance by being applied to general membrane separation processes such as microfiltration, reverse filtration, and the like.

Polymer materials for gas separation and pervaporation membranes that are currently commercialized include polysulfone, cellulose acetate, polycarbonate, polyamide, polyimide, and polyvinylidene fluoride. These membranes show various separation performances depending on the materials. However, when the permeation rate is large, the selectivity is small. On the contrary, when the selectivity is large, the separation performance is small. 'Ideal membrane' can be regarded as a membrane having both high permeation rate and selectivity. Therefore, researchers studying the membrane are actively searching for new membrane materials with the goal of developing an ideal membrane.

For example, a polyimide membrane obtained by using 3,3 ', 4,4'-diphenyltetracarboxylic dianhydride and diamine [US Pat. No. 4,378,400] has an oxygen permeation rate of 0.47 barrers (10 ^-10 cm ³ ( STP) / (cm ³ · cm · gHg)), and the selectivity of oxygen to nitrogen is about 11, which does not satisfy the permeation rate compared to the selectivity.

Recently, studies on 6FDA (hexafluoro dianhydride) polyimide membrane containing CF ₃ -group have been actively conducted. The 6FDA polyimide membrane has excellent permeation rate and selectivity and excellent separation performance compared to conventional membranes. Hoehn et. al. , US Pat. No. 3,899,309 (Dupont), 1975; JJ Chiou et. al ., U.S. Patent No. 5,286,280 to Hoechst, 1994; Japanese Patent Application No. Hei 7-236822 (Japanese ink), 1995; M. Kenji, European Patent Publication No. 0 509 260 A1 (Nitto Denkosa), 1992]. In the case of 6FDA polyimide membrane, the permeation rate of 10 to 30 barrers for carbon dioxide is shown, and the selectivity for carbon dioxide to nitrogen ( ) Shows 20 to 60. As described above, the separation performance of the 6FDA polyimide membrane is the highest separation performance of existing membrane materials, but in order to secure a more economical separation membrane process, a separation membrane having better separation performance is required. The reason why the 6FDA polyimide separator is superior in the separation performance has been explained in various ways, but it is not clear yet, and it is presumed that it is only CF ₃ − contained in 6FDA. Since fluorine group lowers the surface energy of the polymer, it lowers the cohesive energy of the polymer, thereby increasing the non-free volume, and also has a special interaction with carbon dioxide. Therefore, it is expected that the polyamide and polyimide having a high fluorine alkyl group in which fluorine is introduced exhibits excellent carbon dioxide separation characteristics.

On the other hand, as a permeation separation membrane, a polyvinyl alcohol separator for selectively permeating water from a mixture of water and an organic compound and a silicon separator for selectively permeating the organic mixture are commercially available. However, these separators are not only widely limited and limited in application fields, but also require significant improvement in separation performance in order to improve economics. In particular, the silicon-based pervaporation separator which selectively permeates the organic mixture is efficient for the selective separation of chlorine compounds, but is not suitable for the separation of other organic compounds. In addition, since the strength itself is poor to be processed in the form of a composite film, in this case has a disadvantage that the thickness of the thin film. Therefore, there is an urgent need for the development of a hydrophobic pervaporation separation membrane having excellent separation performance capable of selectively separating organic compounds, excellent mechanical strength, and good processability. In this case, the introduction of a fluorine group, which is a bulky, low surface energy hydrophobic group, into polyimide or polyamide can lower the solubility in water and increase the solubility in organic solvents, It can be expected to show good results for separation by pervaporation of organic solvents in water because it can reduce the diffusion resistance.

On the other hand, the ultrafiltration membrane, the microfiltration membrane and the reverse osmosis membrane material include polyamide, polyimide, polysulfone, cellulose acetate, polyacrylonitrile, polymethyl methacrylate, tetrafluorofluoroethylene, polyvinylidene pullolu Polymers, such as a ride, are mainly used. However, most of these materials are hydrophilic and suitable for membrane separation that selectively permeates water, but are not suitable for selective separation of hydrophilic solutes in mixtures in which hydrophilic solutes are mixed with hydrophobic solvents. Generally, a solvent in which the solute to be separated and removed from the liquid mixture is hydrophilic and the solvent dissolving the solute is relatively hydrophobic is to be separated by membrane separation such as ultrafiltration, microfiltration and reverse osmosis. Hydrophobic separators that can selectively permeate are more suitable. As an example, polytetrafluoroethylene and polyvinylidene fluoride membranes are commercially available, which are classified as representative hydrophobic membranes having a critical surface tension of 18 to 30 dynes / cm, but suitable for separations requiring greater hydrophobicity. Otherwise, the permeation rate is so small that the separation performance is not satisfactory and the performance improvement is required. Currently, polyethylene, polypropylene, Teflon, etc. are used as the membrane material, but the membrane having various pores has a disadvantage of poor processability or high manufacturing cost. Therefore, it is desirable to develop a hydrophobic material that is easy to control various shapes and sizes of pores.

The present inventors carefully examined various ways to improve the disadvantages of the conventional separator as described above. As a result, low-energy, bulky perfluorinated alkyl groups can be introduced directly into polyamides, polyimides, polyamide copolymers, polyimide copolymers, and polyimide-amide copolymers, or other polymers or When the membrane is added to or mixed with an inorganic material to form a membrane, or a composite membrane is formed by coating a very thin layer on a support layer of another polymer or inorganic material to form an active layer, the gas permeation membrane and the pervaporation membrane simultaneously have the same permeation rate and selectivity. The present invention has been completed by recognizing that the separation membranes such as ultrafiltration, microfiltration, and reverse osmosis can be arbitrarily improved and the permeation rate can be significantly improved.

Accordingly, the present invention provides a gas separation membrane having better separation performance than the 6FDA polyimide separation membrane, which is known to have the best separation performance to date as a gas separation membrane, and can selectively separate organic compounds or organic solvents in contaminated water. The purpose of the present invention is to provide a permeable evaporation membrane having excellent processability and excellent mechanical strength and excellent separation performance.

In addition, the present invention also provides a hydrophobic ultrafiltration membrane, a microfiltration membrane and a reverse osmosis membrane suitable for separating a liquid mixture in which the solute to be separated and removed is hydrophilic and the solvent dissolving the solute is relatively hydrophobic. There is this.

The present invention is one or two selected from the same equivalent number of diacyl chloride, dianhydride, disulfonyl chloride, dieside and monoacid-monoanhydride and the perfluorinated alkyl-containing diamine represented by the following formula (1) The perfluoroalkyl containing polymer to which the above-mentioned dicarboxylic acid derivative is polycondensed is characterized.

In Chemical Formula 1, R _f may be represented by C (W ₁ W ₂ W ₃ ) (CF ₂ ) _n (X 1) _m (X 2) —, wherein W ₁ , W ₂ and W ₃ are each a hydrogen atom, Fluorine atom, chlorine atom or CF ₃ ; X 1 represents CONR or SO ₂ NR, wherein R represents a hydrogen atom or an alkyl group of C _{1 to} C ₅ ; X2 represents a C ₁ to C ₁₀ alkylene group unsubstituted or substituted with OH or OCOCH ₃ ; n is an integer from 2 to 20; m represents 0 or 1.

In addition, the present invention includes a polymer separation membrane prepared using the above-described polymer as a material.

Referring to the present invention in more detail as follows.

The present invention is a polymer prepared by condensation polymerization of a diamine and a dicarboxylic acid derivative containing a perfluorinated alkyl group having various properties, and a method for preparing the same, and a polymer separation membrane having excellent permeability and hydrophobicity. It relates to a method for producing the same.

Hereinafter, the manufacturing process of the polymer for separator material according to the present invention will be described in detail.

Scheme 1 below shows a process for preparing a perfluorinated alkyl-containing diamine used in the present invention.

First, a dinitrobenzoyl chloride represented by Chemical Formula 2 (DNBC) and a perfluoroalkyl-containing alcohol (R _f OH) having various properties are esterified to obtain a compound represented by Chemical Formula 4, and then, under a Fe metal catalyst Through a nitro reduction reaction to prepare a perfluorinated alkyl-containing diamine represented by the formula (1).

The structure of the perfluorinated alkyl-containing alcohol (R _f OH) used in Scheme 1 serves as a major factor in determining the permeation characteristics of the finally prepared polymer membrane. Therefore, in the present invention, a compound represented by the following formula (3) is selected and used as perfluoroalkyl-containing alcohol (R _f OH).

In Chemical Formula 3, W ₁ , W ₂ and W ₃ each represent a hydrogen atom, a fluorine atom, a chlorine atom or CF ₃ ; X 1 represents CONR or SO ₂ NR, wherein R represents a hydrogen atom or an alkyl group of C _{1 to} C ₅ ; X2 represents a C ₁ to C ₁₀ alkylene group unsubstituted or substituted with OH or OCOCH ₃ ; n is an integer from 2 to 20; m represents 0 or 1.

Specific examples of the perfluoroalkyl-containing alcohol represented by Chemical Formula 3 are as follows: CF ₃ (CF ₂ ) ₈ CONH (CH ₂ ) ₂ OH, CF ₂ Cl (CF ₂ ) (CF ₂ ) ₇ CH ₂ OH, C (F ₂ H) (CF ₂ ) ₉ CH ₂ OH, C (F ₂ Cl) (CF ₂ ) ₁₀ CH ₂ OH, CF ₃ (CF ₂ ) ₇ CH ₂ CH (OH) CH ₂ OH, CF ₃ ( CF ₂ ) ₄ CH ₂ CH (OH) CH ₂ OH, CF ₃ (CF ₂ ) ₄ CH ₂ OH, CF ₃ (CF ₂ ) ₆ (CH ₂ ) ₂ OH, CF ₃ (CF ₂ ) ₆ CH ₂ OH, CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ OH, (CF ₃ ) ₂ CF (CF ₂ ) ₃ (CH ₂ ) OH, CF ₃ (CF ₂ ) ₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ ) ₂ OH, CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₄ OH, CF ₃ (CF ₂ ) ₇ SO ₂ N (CH ₃ ) (CH ₂ ) ₂ OH, CF ₃ (CF ₂ ) ₈ CONH (CH ₂ ) ₂ OH, (CF ₃ ) ₂ CF (CF ₂ ) ₆ (CH ₂ ) ₃ OH, (CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH (COOCH ₃ ) OH, (CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH (OH) CH ₂ OH, CF ₃ (CF ₂ ) ₆ (CH ₂ ) ₂ OH, CF ₃ (CF ₂ ) ₈ (CH ₂ ) ₂ OH.

The perfluorinated alkyl-containing alcohol represented by Chemical Formula 3 may use one kind of monomer homogeneous material, or may use a mixture of several kinds of monomers.

On the other hand, in the present invention by condensation polymerization of the perfluorinated alkyl-containing diamine represented by the formula (1) with a dicarboxylic acid derivative prepared by the above method to produce a polymer represented by the following formula (5a) or (5b).

In the formula: R _f is as defined above and Ar is determined by a dicarboxylic acid derivative.

The polymer represented by Chemical Formula 5a or 5b may be prepared as a single polymer or a copolymer, or in the form of an amide or imide depending on the type and amount of diamine and dicarboxylic acid derivative used in the polymerization reaction. That is, the perfluorinated alkyl-containing diamine represented by the general formula (1) and a single type of dicarboxylic acid derivative are polymerized to prepare a polyamide or polyimide, or two or more types of dicarboxylic acid derivatives are polymerized to form a polyimide copolymer and a polyamide. Copolymers, polyamide-imide copolymers may also be prepared.

Referring to the manufacturing process of the polymer used as a membrane material of the present invention in more detail.

The dicarboxylic acid derivative having the same number of dicarboxylic acid derivatives as the equivalent of 1 equivalent of the perfluoroalkyl-containing diamine represented by Chemical Formula 1 is polymerized in the same manner as the known condensation polymerization method in a polar organic solvent. At this time, as the polar organic solvent, N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), 1-methyl-2-pyrrolidinone (NMP), dimethyl sulfoxide (DMSO ), Tetrahydrofuran (THF) and the like.

The dicarboxylic acid used in the polycondensation reaction according to the present invention may be selected from the group consisting of diacyl chlorides, dianhydrides, disulfonyl chlorides, diesides, and monoacid-monoanhydrides. Is used.

As the diacyl chlorides, both aromatic and aliphatic may be used, and as aromatic diacyl chloride, for example, terephthaloyl chloride, isophthaloyl chloride, etc. may be used, and as aliphatic diacyl chloride, for example, oxalic chloride, Malonic chloride, succinic chloride, adipoyl chloride and the like can be used. In terms of characteristics, reactivity, and price of the membrane, as the diacyl chloride, it is more preferable that 1-2 benzene rings are contained, such as terephthaloyl chloride or isophthaloyl chloride. Dianehydrides include pyromellitic dianhydrides (PMDA), 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydrides (BTDA), oxydiphthalic dianhydrides (ODPA), hexaful Luoroisopropylidene diphthalic dianhydride (6FDA) and biphenyl tetracarboxylic dianhydride (BPDA) are used. As disulfonyl chlorides, both aromatic and aliphatic may be used. In the case of aromatic disulfonyl chloride, 1,4-benzenedisulfonyl chloride and its isomers are the best because of the low manufacturing cost. As the diesides, those having the same internal structure as the above-described diacyl chloride are the best in terms of price. As monoacid-monoacyl chloride, trimellitic anhydride is most preferable.

In addition, in performing the condensation polymerization reaction, a perfluorinated alkyl-containing diamine represented by Chemical Formula 1 may be mixed with diamines having no fluorine substitution so as to easily control properties required for a membrane application system. In consideration of the above, the fluorine-substituted diamines may be contained within a range of less than 80% by weight relative to the siloxanediamine represented by the formula (1). Diamines that can be used together with perfluoroalkyl-containing diamines can be used both aromatic and aliphatic. Among them, as aromatic diamines, for example, m-phenylenediamine, p-phenylenediamine, diaminobenzoic acid, Diaminosulfonic acid, methylenedianiline, 1,3,5-trimethyl-2,6-petylenediamine, oxydianiline, i-propylidenedianiline and the like are preferable in terms of price.

On the other hand, the present invention includes a polymer separation membrane using a polymer represented by the above formula 5a or 5b prepared by the above condensation polymerization. Polymer membrane according to the present invention is a direct separation membrane using at least one polyamide, polyimide, polyamide copolymer, polyimide copolymer, polyamide-imide copolymer represented by the formula (5a or 5b) as the membrane material The separator may be prepared by mixing or adding to another polymer or inorganic material such as alumina or silica, or to a metal powder such as aluminum or iron, or by coating a very thin layer on another polymer or ceramic support layer to surface the perfluoroalkyl group. The composite separator may be formed by forming an active layer of an oriented thin film. Even when the copolymer is used as an active layer material, the content and type of the perfluoroalkyl group-containing homopolymer or the copolymer monomer may be changed to optimize the critical surface tension and the separation system to which the perfluoroalkyl group side chain structure is to be applied. On the other hand, in the case of making a membrane using the polymer according to the present invention or in the preparation of the active layer of the composite membrane, the number average molecular weight of the polymer is preferably in the range of 5,000 to 100,000, and the membrane is mixed or added to other polymers or inorganic materials. When making, the number average molecular weights are suitable for the range of 1,0000-100,000.

The polymer that can be used together in the preparation of the polymer membrane according to the present invention is conventionally used as a separator material, for example, polyamide, polyimide, polysulfone, cellulose acetate, polyacrylonitrile, polymethyl methacrylate, Tetrafluorofluoroethylene, polyvinylidene fluoride, and the like. In this case, even if a polymer having a small amount of perfluorinated alkyl group is used, the critical surface tension of the commercially used polymer is very low (since large hydrophobicity), so that most of the perfluorinated alkyl group is oriented on the outermost surface of the separator and used in small amounts. Excellent surface modification effect can also be obtained.

The polymer separation membrane prepared in the present invention may be manufactured in the form of asymmetric or composite membrane, and may be manufactured as a flat plate, tube type, hollow fiber type or spiral wound type membrane to be suitable for the separation system to be applied. In addition, by using a conventional phase transition method to prepare a variety of uses, such as gas separation membrane, permeation evaporation membrane, microfiltration membrane, ultrafiltration membrane, reverse osmosis membrane, etc. Can be used as The coating method for manufacturing a composite separator may use a conventional method such as spray coating, solution deposition coating or spin coating.

Thus, membrane separation processes such as gas separation, pervaporation, microfiltration, ultrafiltration, or reverse osmosis, which apply the polymer separation membrane according to the present invention, exhibit separation performance that cannot be achieved with conventional membranes or breakthrough disadvantages of existing processes. Will improve. In particular, in gas separation, permeation rate and selectivity of the various gas mixtures are significantly improved at the same time than the 6FDA polyimide membrane, which is known to have the best separation performance.

Meanwhile, in the preparation of the polymer separation membrane according to the present invention, the perfluorinated alkyl-containing diamine represented by Formula 1 may be prepared according to the selective use of the perfluorinated alkyl-containing alcohol represented by Formula 3 above, It is possible to control the permeation characteristics of the polymer membrane prepared according to. This effect is also fully possible by the various selected uses of dicarboxylic acid derivatives. In addition, by changing the content and type of the diamines perfluoroalkyl-containing diamine and fluorine unsubstituted during the polycondensation reaction, or using both diacyl chloride and dianhydride simultaneously By controlling, the non-free volume and surface energy, mechanical strength, solubility, etc. of the prepared membrane material can be freely adjusted, thereby optimizing for the separation system to be applied such as permeation characteristics of gas separation and pervaporation. There is this.

In particular, even in the case of pervaporation separation, it is possible to prepare a hydrophobic separator having excellent separation performance capable of selectively separating volatile organic compounds (VOC) in water. In addition, ultrafiltration, microfiltration, and reverse osmosis separation selectively separates hydrophilic solutes from mixtures containing hydrophilic solutes in hydrophobic solvents.The permeation rate of hydrophobic solvents is higher than that of conventional membranes having surface properties suitable for mechanical strength and permeability. It is possible to produce a hydrophobic separator which can be greatly improved. When these are mixed with other existing membrane materials and processed into the form of hollow yarns or composite membranes, their properties can be further improved.

As described above, the polymer membrane according to the present invention is a gas separation membrane of a fluorine-based material having excellent processability and excellent mechanical strength with low surface energy, such as CO ₂ / N ₂ , CO ₂ / CH ₄ , CO / H ₂ , O ₂ , / N ₂ , CH ₄ / N ₂ , CO ₂ / H ₂ , water vapor in the gas, or volatile organic substances (VOC) in the air, etc. can be used to remove permeation rate and selectivity Improved volatile organic substances (VOC) dissolved in water, hydrocarbons or water or hydrophilic substances contained in small amounts, or oil or hydrocarbon and water dispersions or emulsion mixtures. It is also useful as a permeation separator, steam permeation membrane, microfiltration membrane, ultrafiltration membrane, or reverse osmosis membrane.

Since the polymer according to the present invention has a perfluorinated alkyl group substituted as a side chain, the hydrophobic perfluorinated alkyl group has a strong tendency to be oriented toward the air side with low surface energy, which is somewhat different depending on the content of the perfluorinated alkyl group. Is very low, shows a low critical surface tension of about 15 to 30 dynes / cm, a very large contact angle to water of 90 to 120 °, and a contact angle of 66 to 100 ° for hydrophobic diodomethane. . In addition, the hydrophilicity and hydrophobicity of the polymer membrane according to the present invention can be arbitrarily controlled, for example, the hydrophilicity of the polymer membrane finally prepared according to the amount of perfluorinated alkyl-containing diamine represented by Chemical Formula 1 used in preparing the polymer. Hydrophobicity can be arbitrarily adjusted.

On the other hand, the perfluorinated alkyl-containing polymer according to the present invention has a relatively large volume of the perfluoroalkyl group side chain and a very large van der Waals volume of fluorine in the side chain. Therefore, the packing density of the perfluorinated alkyl-containing polymer according to the present invention is estimated to be relatively low compared to other polymers. Due to such a low packing density, the permeation rate of the gas, hydrophobic vapor, and hydrophobic liquid of the prepared polymer membrane can be greatly improved. In addition, the affinity for each gas may vary due to electrostatic interactions resulting from a plurality of fluorine atoms in the perfluorinated alkyl group structure, and thus, a specific improvement in selectivity may be expected for a specific gas mixture. Therefore, the polymer separation membrane made of a perfluoroalkyl-containing polymer according to the present invention can be expected to be accompanied by a significant increase in selectivity and permeation rate for a specific gas mixture and liquid mixture.

Such a present invention will be described in more detail based on the following examples, but the present invention is not limited thereto.

Example 1 Synthesis of Perfuluroalkylethyl-3,5-dinitrobenzoate (PFDNB)

A 250 ml three necked flask equipped with a nitrogen gas inlet tube, agitator and dropping funnel was immersed in an ice bath, followed by a solution of dinitrobenzoyl chloride (DNBC; 10 g, 0.047 mol) dissolved in 94 ml of methylene chloride. The mixture was stirred vigorously at room temperature.

In a separate vessel, methylene perfluorofluoroalkylethanol (PFOH: CF ₃ (CF ₂ ) ₈ CONH (CH ₂ ) ₂ OH, 0.056 mol, 1.2 eqv.) And triethylamine (TEA; 0.066 mol, 1.4 eqv.) Dissolved separately in 113 mL of chloride. Thereafter, the above-described DNBC solution was added to the PFOH reaction solution for 1 hour through a dropping funnel while vigorously stirring in a nitrogen gas atmosphere. After stirring for an additional 2 hours the product was washed with an aqueous NaHCO ₃ solution (100 mL × 3) in a 500 mL separatory funnel and then dried PFDNB under vacuum. Then washed with hexane / ethyl acetate (10/1, v / v) to wash the excess PFA, then dried to give the product (yield 99.9%). And recrystallized from ethyl acetate / hexane (73.2% yield).

The structure and purity of the product were confirmed by ¹ H-NMR, ¹³ C-NMR, FTIR, Mass, gas chromatography. IR (KBr) confirmed 3094 cm ^-1 (C = CH str., Aromatic), 1736 cm ^-1 (C = O str., Ester), 1629 cm ^-1 (C = C str., Aromatic), 1545 Characteristic peaks were identified at cm ⁻¹ (CN str., NO ₂ ), 1350 cm ⁻¹ (CN str., NO ₂ ).

Example 2 Synthesis of Perfuluroalkylethyl 3,5-Diaminobenzoate (PFDAB)

Into a 500 ml three-necked flask equipped with a reflux condenser, a stirrer, and a nitrogen gas inlet tube, PFDNB (22 g, 0.0394 mol) prepared in Example 1, glacial acetic acid (120 ml) and water (8 ml) were charged and heated. Fe metal powder (100 mesh; 26 g, 0.4654 mol) was added five times for 0.5 hour while stirring, and the temperature of the reactant was maintained at 25 ° C. The reaction during the addition of the Fe metal powder is exothermic and thus requires intermittent cooling (water bath). If the particle size of the Fe metal powder exceeds 100 mesh, there is a problem that the reaction becomes violent. After all of the Fe metal powder was added to maintain an additional 2 hours. The heterogeneous product was extracted with ethyl acetate and then filtered using celite. The filtrate was washed three times with water and aqueous NaHCO ₃ solution and then dried under vacuum. PFDAB residue was recrystallized from ethyl acetate / hexanes (11.10 g, yield 56.6%).

The structure and purity characteristics of the prepared PFDAB were confirmed by ¹ H-NMR, ¹³ C-NMR, FTIR, Mass, gas chromatography. As a result, the calculated molecular weight (498.24) and the Mass test result (498) were in good agreement. IR (KBr) measurements showed characteristic peaks at 3455 and 3357 cm ^-1 (NH str. Amine), 1736 cm ^-1 (C = O str. Ester), and 1366 cm ^-1 (CN str. Amine). .

Example 3 Synthesis of Perfluoroalkyl-containing Diamines (PFDAB)

Next, the perfluoroalkyl-containing diamine (PFDAB) was synthesized by performing the same procedure as in Examples 1 and 2 using a perfluoroalkyl-containing alcohol (PFOH) as shown in Table 1 below.

The test results were in good agreement with the calculated molecular weights of the finally prepared perfluorinated alkyl-containing diamine. In addition, the IR (KBr) of all the perfluorinated alkyl-containing diamines prepared was 3455 and 3357 cm ^-1 (NH str. Amine), 1736 cm ^-1 (C = O str. Ester), 1366 cm ^-1 ( CN str.amine) showed characteristic peaks.

Example 4 Preparation of Polyimide

In a 50 ml four-necked flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet tube, and a thermometer, 1-methyl-2-pyrrolidinone (30) was prepared in each of the perfluoroalkyl-containing diamines (PFDAB) prepared in Example 3. Ml), and then added the same amount of hexafulurodian hydride (6FDA) and stirred. At this time, the content of the solid was adjusted to 15% by weight. When the solution was stirred for 2 hours or more, a high viscosity polyamic acid solution was prepared. The prepared polyamic acid solution was heated to 190 ℃ and maintained for 24 hours to prepare a transparent polyimide solution. In the case of soluble polyimide, polyimide was prepared by precipitating fine powder in water using a homogenizer and washing and drying with methanol.

Example 4-1 Preparation of Polyimide Membrane

The polyimide prepared above was dissolved in tetrahydrofuran (THF) at 10% by weight, and the solution was formed into a predetermined thickness on a glass plate. The glass plate was dried in vacuo for 6 hours at room temperature, and then cooled immediately after holding at 80 ° C. for 12 hours, at 150 ° C. for 1 hour, and at 250 ° C. for 1 hour. The prepared polyimide membrane was removed and cut to a predetermined size to be used in the experiment.

The results of permeation of the CO ₂ / N ₂ mixed gas using the prepared perfluorinated alkyl-containing polyimide membrane are shown in Table 2 below.

Example 4-2 Preparation of Polyimide Hollow Fiber Membrane

The polyimide prepared above was dissolved in tetrahydrofuran (THF) at 15% by weight, and a pore-forming agent, propionic acid, was added in an amount of 1/2 to the polyimide to obtain a polymer solution. The prepared polymer solution was spun through a double tube spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 50 cm. The spinning rates of the polymer solution and the internal coagulant were 10 cc / min and 5 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.3 mm, an outer diameter of 0.6 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm. The performance of the manufactured hollow fiber membrane is shown in Table 3 below.

In order to perform the separation experiment for pervaporation of the hollow fiber membrane prepared above, 10 ^-3 Torr was applied at 25 ° C using an aqueous solution containing 1000 ppm of trichloroethylene, and the results are shown in Table 4 below. .

Example 4-3 Preparation of Membrane for Polyimide Ultrafiltration

Ultrafiltration membranes were manufactured in the form of flat plate and hollow fiber by the following method.

The polyimide prepared above was dissolved in tetrahydrofuran at 15% by weight, and polyethylene glycol as a pore-forming agent was added to the polyimide in the same amount to obtain a polymer solution.

In order to produce a flat plate, a non-woven fabric was cast with a doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by immersion in water at 4 ° C. or lower for 1 hour.

In order to manufacture the hollow fiber type, the polymer solution before casting was spun through a spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 30 cm. The spinning rates of the polymer solution and the internal coagulant were 7 cc / min and 10 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.5 mm, an outer diameter of 1.0 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm.

The performance evaluation experiments of the plate and hollow fiber membranes prepared above were carried out under a pressure of 1 kgf / cm 2 at 25 ° C. for kerosene in which 5000 ppm of water was dispersed in a size of 1 to 10 μm. The results are shown in Table 5 below.

Example 4-4 Preparation of Separator for Polyimide Reverse Osmosis

The polyimide prepared above was dissolved in a dimethylacetamide / tetrahydrofuran mixed solution at 15% by weight, and lithium chloride (LiCl) as a swelling agent was added in an amount equivalent to 10% with respect to the solvent to prepare a polymer solution. Got it. The polymer solution was cast on a polyester nonwoven fabric with a Doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by dipping for 1 hour in a water / ethanol mixed solution below 4 ° C. After deposition, heat treatment was performed for 15 minutes in water at 90 ° C.

Evaluation of the performance of the asymmetrical flat film formed in this way was performed by 5% of the water is fine particles of 0.001 ~ 0.1 ㎛ by the mixture of sodium lauryl sulfate (SLS) and cetyl alcohol surfactant (10% of the amount of water) W / O microemulsion emulsified in n-dodecane was carried out at 25 ℃ and the application pressure of 40 kgf / ㎠, the results are shown in Table 6.

Example 5 Preparation of Polyamide

In a 50 ml four-necked flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet tube, and a thermometer, each of 1-methyl-2-pyrrolidinone (NMP) was prepared with the perfluoroalkyl-containing diamine (PFDAB) prepared in Example 3. 30 mL), and then added the same amount of terephthaloyl chloride and stirred. At this time, the content of the solid was adjusted to 15% by weight. The solution was stirred for at least 12 hours to prepare a high viscosity polyamide solution. The polyamide solution thus prepared was precipitated in a fine powder state in a water using a homogenizer, washed with methanol, and dried to prepare polyamide.

Example 5-1 Preparation of Polyamide Membrane

The polyamide prepared above was dissolved in 1-methyl-2-pyrrolidinone (NMP) at 10% by weight, and this solution was formed into a predetermined thickness on a glass plate. The glass plate was dried in vacuo for 6 hours at room temperature, and then cooled immediately after holding at 80 ° C. for 12 hours, at 150 ° C. for 1 hour, and at 250 ° C. for 1 hour. The polyamide separator thus prepared was removed and cut into a predetermined size to be used in the experiment.

The results of permeation of the CO ₂ / N ₂ mixed gas using the prepared perfluorinated alkyl-containing polyamide separation membrane are shown in Table 7 below.

Example 5-2 Preparation of Polyamide Hollow Fiber Membrane

The polyamide prepared above was dissolved in tetrahydrofuran (THF) at 15% by weight, and a pore-forming agent, propionic acid, was added in an amount of 1/2 to the polyamide to obtain a polymer solution. The prepared polymer solution was spun through a double tube spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 50 cm. The spinning rates of the polymer solution and the internal coagulant were 10 cc / min and 5 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.3 mm, an outer diameter of 0.6 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm. The performance of the manufactured hollow fiber membrane is shown in Table 8 below.

In order to perform the separation experiment for pervaporation of the hollow fiber membrane prepared above, 10 ⁻³ Torr was applied at 25 ° C. using an aqueous solution containing 500 ppm of toluene, and the results are shown in Table 9 below.

Example 5-3 Preparation of Membranes for Polyamide Ultrafiltration

Ultrafiltration membranes were manufactured in the form of flat plate and hollow fiber by the following method.

The polyamide prepared above was dissolved in 15% by weight in a mixed solution of dimethylacetamide / tetrahydrofuran (30/70, w / w), and polyethylene glycol as a pore-forming agent was added in an equal amount to the polyamide. A polymer solution was obtained.

In order to produce a flat plate, a non-woven fabric was cast with a doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by immersion in water at 4 ° C. or lower for 1 hour.

In order to manufacture the hollow fiber type, the polymer solution before casting was spun through a spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 30 cm. The spinning rates of the polymer solution and the internal coagulant were 15 cc / min and 10 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.5 mm, an outer diameter of 0.8 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm.

The performance evaluation experiments of the plate and hollow fiber membranes prepared above were carried out under a pressure of 1 kgf / cm 2 at 25 ° C. for kerosene in which 5000 ppm of water was dispersed in a size of 1 to 10 μm. The results are shown in Table 10 below.

Example 5-4 Preparation of Polyamide Reverse Osmosis Membrane

The polyamide prepared above was dissolved in 15% by weight of dimethylacetamide / tetrahydrofuran mixed solution, and lithium chloride (LiCl) as a swelling agent was added in an amount corresponding to 10% of the solvent to prepare a polymer solution. Got it. The polymer solution was cast on a polyester nonwoven fabric with a Doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by dipping for 1 hour in a water / ethanol mixed solution below 4 ° C. After deposition, heat treatment was performed for 15 minutes in water at 90 ° C.

Evaluation of the performance of the asymmetrical flat film formed in this way was performed by 5% of the water is fine particles of 0.001 ~ 0.1 ㎛ by the mixture of sodium lauryl sulfate (SLS) and cetyl alcohol surfactant (10% of the amount of water) W / O microemulsion emulsified in n-dodecane was carried out at 25 ℃ and the application pressure of 40 kgf / ㎠, the results are shown in Table 11.

Example 6 Preparation of Polyimide Copolymer

The same amount as 1,3-phenylenediamine (p-PDA; 1.15 g) purified by sublimation was mixed with 50/50 weight ratio of difluorinated alkyl-containing diamine (PFDAB) prepared in Example 3. It was added to the reactor with 1-methyl-2-pyrrolidinone (NMP; 6 cc) and dissolved. Hexapulolo dianhydride (6DFA), vacuum dried at 160 ° C. for 48 hours, was charged into the reactor by the same amine equivalent and reacted. The reaction was carried out at room temperature for 5 hours to obtain an intermediate polyamic acid (PAA). 5 equivalents and 4 equivalents of acetic anhydride and pyridine were added to the synthesized PAA solution with respect to diamine and dianhydride, respectively, and reacted at 70 ° C. for 12 hours to obtain a 6DFA polyimide copolymer soluble in a solvent. The solution containing 6DFA polyimide copolymer was precipitated in methanol (400 mL) and filtered. The filtrate was precipitated twice in methanol to obtain a precipitate. The precipitate was filtered off and dried for 24 hours at 160 ° C. and vacuum.

Example 6-1 polyimide copolymer separation membrane

The results of permeation of the CO ₂ / N ₂ mixed gas using the prepared perfluorinated alkyl-containing polyimide copolymer separation membrane are shown in Table 12 below.

Example 6-2 Preparation of Polyimide Copolymer Hollow Fiber Membrane for Gas Separation

The polyimide copolymer prepared above was dissolved in tetrahydrofuran / acetone (50/50, w / w) at 15% by weight, and a pore-forming agent, propionic acid, was added in an amount of 1/2 to the polyamide. A polymer solution was obtained. The prepared polymer solution was spun through a double tube spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 50 cm. The spinning rates of the polymer solution and the internal coagulant were 10 cc / min and 5 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.3 mm, an outer diameter of 0.6 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm. The performance of the manufactured hollow fiber membrane is shown in Table 13 below.

In order to perform the separation experiment for pervaporation of the hollow fiber membrane prepared above, 10 ⁻³ Torr was applied at 25 ° C. using an aqueous solution containing 2000 ppm of chloroform, and the results are shown in Table 14 below.

Example 6-3 Preparation of Polyimide Copolymer Ultrafiltration Membranes

Ultrafiltration membranes were manufactured in the form of flat plate and hollow fiber by the following method.

The polyimide copolymer prepared above was dissolved in tetrahydrofuran at 15% by weight, and polyethylene glycol as a pore-forming agent was added to the polyimide copolymer in the same amount to obtain a polymer solution.

In order to produce a flat plate, a non-woven fabric was cast with a doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by immersion in water at 4 ° C. or lower for 1 hour.

In order to manufacture the hollow fiber type, the polymer solution before casting was spun through a spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 30 cm. The spinning rates of the polymer solution and the internal coagulant were 10 cc / min and 10 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.5 mm, an outer diameter of 0.8 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm.

The performance evaluation experiments of the plate and hollow fiber membranes prepared above were carried out under a pressure of 1 kgf / cm 2 at 25 ° C. for kerosene in which 5000 ppm of water was dispersed in a size of 1 to 10 μm. The results are shown in Table 15 below.

Example 6-4 Preparation of Polyamide Reverse Osmosis Membrane

The polyimide copolymer prepared above was dissolved in 15% by weight of dimethylacetamide / tetrahydrofuran mixed solution, and lithium chloride (LiCl) as a swelling agent was added in an amount equivalent to 10% with respect to the solvent. A solution was obtained. The polymer solution was cast on a polyester nonwoven fabric with a Doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by dipping for 1 hour in a water / ethanol mixed solution below 4 ° C. After deposition, heat treatment was performed for 15 minutes in water at 90 ° C.

Evaluation of the performance of the asymmetrical flat film formed in this way was performed by 5% of the water is fine particles of 0.001 ~ 0.1 ㎛ by the mixture of sodium lauryl sulfate (SLS) and cetyl alcohol surfactant (10% of the amount of water) The W / O microemulsion emulsified in n-dodecane was carried out at 25 ° C. and 40 kgf / cm 2 application pressure, and the results are shown in Table 16 below.

Example 7 Preparation of Polyamide Copolymer

In a 50 ml four-necked flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet tube, and a thermometer, p-phenylenediamine and the perfluorinated alkyl-containing diamine (PFDAB) prepared in Example 3 were added at a 30/70 weight ratio. The solution was dissolved in 1-methyl-2-pyrrolidinone (NMP; 30 mL), and then an equivalent of isophthaloyl chloride was added thereto and stirred. At this time, the content of the solid was adjusted to 15% by weight. The solution was stirred for at least 12 hours to prepare a high viscosity polyamide solution. The polyamide solution thus prepared was precipitated in a fine powder state in a water using a homogenizer, washed with methanol, and dried to prepare a polyamide copolymer.

Example 7-1 Preparation of Polyamide Copolymer Membrane

The polyamide copolymer prepared above was dissolved in 1-methyl-2-pyrrolidinone (NMP) at 10% by weight, and the solution was formed into a predetermined thickness on a glass plate. The glass plate was dried in vacuo for 6 hours at room temperature, and then cooled immediately after holding at 80 ° C. for 12 hours, at 150 ° C. for 1 hour, and at 250 ° C. for 1 hour. The polyamide separator thus prepared was removed and cut into a predetermined size to be used in the experiment.

The results of permeation of the CO ₂ / N ₂ mixed gas using the prepared perfluorinated alkyl-containing polyamide copolymer separation membrane are shown in Table 17 below.

Example 7-2 Preparation of Polyamide Copolymer Hollow Fiber Membrane

The polyamide copolymer prepared above was dissolved in a mixed solution of tetrahydrofuran / acetone (70/30, w / w) at 15% by weight, and the poionic forming agent, propionic acid, was dissolved in 1 /% of the polyamide copolymer. It was added in 2 quantities to obtain a polymer solution. The prepared polymer solution was spun through a double tube spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 50 cm. The spinning rates of the polymer solution and the internal coagulant were 10 cc / min and 5 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.3 mm, an outer diameter of 0.6 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm. The performance of the manufactured hollow fiber membrane is shown in Table 18 below.

In order to perform the separation experiment for pervaporation of the hollow fiber membrane prepared above, 10 ^-3 Torr was applied at 25 ° C using an aqueous solution containing 500 ppm of toluene, and the results are shown in Table 19 below.

Example 7-3 Preparation of Polyamide Copolymer Ultrafiltration Separator

Ultrafiltration membranes were manufactured in the form of flat plate and hollow fiber by the following method.

The polyamide copolymer prepared above was dissolved in tetrahydrofuran at 15% by weight, and polyethylene glycol as a pore-forming agent was added to the polyamide in the same amount to obtain a polymer solution.

In order to produce a flat plate, a non-woven fabric was cast with a doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by immersion in water at 4 ° C. or lower for 1 hour.

In order to manufacture the hollow fiber type, the polymer solution before casting was spun through a spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 30 cm. The spinning rates of the polymer solution and the internal coagulant were 15 cc / min and 10 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.5 mm, an outer diameter of 0.8 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm.

The performance evaluation experiments of the plate and hollow fiber membranes prepared above were carried out under a pressure of 1 kgf / cm 2 at 25 ° C. for kerosene in which 5000 ppm of water was dispersed in a size of 1 to 10 μm. The results are shown in Table 20 below.

Example 7-4 Preparation of Polyamide Copolymer Reverse Osmosis Membrane

The polyamide prepared above was dissolved in 15% by weight of dimethylacetamide / tetrahydrofuran mixed solution, and lithium chloride (LiCl) as a swelling agent was added in an amount corresponding to 10% of the solvent to prepare a polymer solution. Got it. The polymer solution was cast on a polyester nonwoven fabric with a Doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by dipping for 1 hour in a water / ethanol mixed solution below 4 ° C. After deposition, heat treatment was performed for 15 minutes in water at 90 ° C.

Evaluation of the performance of the asymmetrical flat film formed in this way was performed by 5% of the water is fine particles of 0.001 ~ 0.1 ㎛ by the mixture of sodium lauryl sulfate (SLS) and cetyl alcohol surfactant (10% of the amount of water) W / O microemulsion emulsified in n-dodecane was carried out at 25 ℃ and the application pressure of 40 kgf / ㎠, the results are shown in Table 21.

Example 8 Preparation of Polyamide-Imid Copolymer

In a 50 ml four-necked flask equipped with a reflux condenser, stirrer, nitrogen gas inlet tube and thermometer, CF ₃ (CF ₂ ) ₈ (CH ₂ ) ₂ OH as a perfluoroalkyl diamine (PFDAB) was added 1-methyl- After dissolving in 2-pyrrolidinone (NMP; 30 ml), one compound selected from the same equivalent of PMDA, BTDA and ODPA, isophthaloyl chloride (IPC), terephthaloyl chloride (TPC) and adipoyl chloride ( 1 type of dieside monomer selected from IDC) was added and stirred. At this time, the content of the solid was adjusted to 15% by weight. The solution was stirred for at least 12 hours to prepare a high polyamide-imide copolymer solution. The polyamide-imide copolymer solution thus prepared was precipitated in a fine powder state in a water using a homogenizer, and then washed and dried in methanol to prepare a polyamide-imide copolymer.

Example 8-1 Preparation of Polyamide-Imide Copolymer Separator

The polyamide-imide copolymer prepared above was dissolved in 1-methyl-2-pyrrolidinone (NMP) at 10% by weight, and the solution was formed into a predetermined thickness on a glass plate. The glass plate was dried in vacuo for 6 hours at room temperature, and then cooled immediately after holding at 80 ° C. for 12 hours, at 150 ° C. for 1 hour, and at 250 ° C. for 1 hour. The prepared polyamide-imide copolymer separation membrane was removed and cut into a predetermined size to be used in the experiment.

The results of permeation of the CO ₂ / N ₂ mixed gas using the prepared perfluorinated alkyl-containing polyamide-imide copolymer separation membrane are shown in Table 22 below.

Example 8-2 Preparation of Polyamide Copolymer Hollow Fiber Membrane for Gas Separation

The polyamide-imide copolymer prepared above was dissolved in a mixed solution of tetrahydrofuran / acetone (70/30, w / w) at 15% by weight, and the propionic acid, which is a pore-forming agent, was polyamide-imide The polymer solution was obtained by adding in an amount of 1/2 to the copolymer. The prepared polymer solution was spun through a double tube spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 50 cm. The spinning rates of the polymer solution and the internal coagulant were 10 cc / min and 5 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.3 mm, an outer diameter of 0.6 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm. The performance of the manufactured hollow fiber membrane is shown in Table 23 below.

In order to perform the separation experiment for pervaporation of the hollow fiber membrane prepared above, 10 ⁻³ Torr was applied at 25 ° C. using an aqueous solution containing 500 ppm of toluene, and the results are shown in Table 24 below.

Example 8-3 Preparation of Polyamide-Imide Copolymer Ultrafiltration Separator

Ultrafiltration membranes were manufactured in the form of flat plate and hollow fiber by the following method.

The polyamide-imide copolymer prepared above was dissolved in tetrahydrofuran at 15% by weight, and polyethylene glycol as a pore-forming agent was added to the polyamide in the same amount to obtain a polymer solution.

In order to produce a flat plate, a non-woven fabric was cast with a doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by immersion in water at 4 ° C. or lower for 1 hour.

In order to manufacture the hollow fiber type, the polymer solution before casting was spun through a spinneret. At this time, the internal coagulant and the external coagulant were used water / ethanol mixed solution (50/50, v / v) and water of less than 4 ℃, respectively, the gap (gap) was 30 cm. The spinning rates of the polymer solution and the internal coagulant were 15 cc / min and 10 cc / min, respectively. The hollow fiber membrane obtained at this time was an inner diameter of 0.5 mm, an outer diameter of 0.8 mm, and was made of a module in which 10 strands were potted with epoxy resin at 30 cm.

The performance evaluation experiments of the plate and hollow fiber membranes prepared above were carried out under a pressure of 1 kgf / cm 2 at 25 ° C. for kerosene in which 5000 ppm of water was dispersed in a size of 1 to 10 μm. The results are shown in Table 25 below.

Example 8-4 Preparation of Separation Membrane for Polyamide-Imide Copolymer Reverse Osmosis

The polyamide-imide prepared above was dissolved in 15% by weight of dimethylacetamide / tetrahydrofuran mixed solution, and lithium chloride (LiCl) as a swelling agent was added in an amount corresponding to 10% of the solvent. A polymer solution was obtained. The polymer solution was cast on a polyester nonwoven fabric with a Doctor's knife, evaporated in an air at 25 ° C. for 1 minute, and solidified by dipping for 1 hour in a water / ethanol mixed solution below 4 ° C. After deposition, heat treatment was performed for 15 minutes in water at 90 ° C.

Evaluation of the performance of the asymmetrical flat film formed in this way was performed by 5% of the water is fine particles of 0.001 ~ 0.1 ㎛ by the mixture of sodium lauryl sulfate (SLS) and cetyl alcohol surfactant (10% of the amount of water) W / O microemulsion emulsified in n-dodecane was carried out at 25 ℃ and the application pressure of 40 kgf / ㎠, the results are shown in Table 26.

Example 9 Preparation of Polyimide Composite Membrane

A gas separation membrane was prepared by mixing the perfluorinated alkyl-containing 6FDA polyimide prepared in Example 4 with polysulfone (UDEL P-3500) and the separation performance was measured.

2 g of the prepared 6DFA polyimide and 0.04 g of polysulfone were dissolved in 20 g of dimethylacetamide to obtain a polymer solution. The polymer solution was cast to a certain thickness using a doctor's knife and then heat-treated at 60 ° C. to 250 ° C. for 6 hours using a vacuum oven to form a film. The membrane obtained through this process was used to measure the resolution of the mixed gas pairs of CO ₂ / CH ₄ and CO ₂ / N ₂ , and 10 ^-3 at 25 ° C using an aqueous solution in which 250 ppm of hexane was dissolved. The separation test results for pervaporation when Torr is applied are shown in Table 27 below.

Example 10 Preparation of Polyimide Copolymer Composite Membrane

1 g of the perfluoroalkyl-containing polyimide copolymer prepared in Example 6 was dissolved in 10 g of a mixed solution of tetrahydrofuran / dimethylacetamide (50/50, w / w) to prepare a polymer solution. The polymer solution was added dropwise onto the polytetrafluoroethylene ultrafiltration separator and spin coated at 500 rpm for 1 minute. This was dried for 5 hours from 60 ℃ to 120 ℃ under vacuum conditions to prepare a composite membrane. As a result of measuring the resolution of the mixed gas pairs of CO ₂ / CH ₄ and CO ₂ / N ₂ with the composite membrane obtained through the above process, using an aqueous solution in which 250 ppm of methylene dichloride was dissolved at 25 ° C The separation test results for pervaporation when 10 ^-3 Torr is applied are shown in Table 28 below.

Example 11 Preparation of Polyamide Copolymer Composite Membrane

0.1 g of the perfluorinated alkyl-containing polyamide copolymer prepared in Example 7 and 10 g of polyvinyl chloride (PVC) were dissolved in 50 ml of tetrahydrofuran to prepare a polymer solution. The polymer solution was cast at a predetermined thickness using a doctor's knife, and then dried in a vacuum oven at 25 ° C. for 12 hours to obtain a gas permeable membrane and a permeation membrane. The membrane obtained through this process was used to measure the resolution of the mixed gas pairs of CO ₂ / CH ₄ and CO ₂ / N ₂ , and 10 ^-3 at 25 ° C using an aqueous solution containing 500 ppm of toluene. The separation test results for pervaporation when Torr is applied are shown in Table 29 below.

As described above, the polymer membrane of the present invention, in particular, selectively separates various gas mixtures such as CO ₂ , N ₂ , O ₂ , CH ₄ , H ₂ , NH ₃ , water vapor, hydrocarbon gas, and volatile organic substances. Separation membrane for gas separation, hydrophobic separation membrane for selectively separating volatile organic substances dissolved in water, ultrafiltration separation or microfiltration separation for separating oil or hydrocarbon and water dispersion mixture or emulsion, etc. It is suitable as a hydrophobic membrane for reverse osmosis separating a hydrophilic material having a low molecular weight dissolved in it, and a hydrophobic hollow fiber support material for liquid impregnation of a membrane contactor.

Claims (10)

One or two or more dicarboxylic acids selected from the same equivalent number of diacyl chlorides, dianhydrides, disulfonyl chlorides, diesides, and monoacid-monoanhydrides with the perfluorinated alkyl-containing diamine represented by the following Chemical Formula 1 A polymer separation membrane, characterized in that the derivative is made of a perfluorinated alkyl-containing polymer material. Formula 1 In Chemical Formula 1, R _f may be represented by C (W ₁ W ₂ W ₃ ) (CF ₂ ) _n (X 1) _m (X 2) —, wherein W ₁ , W ₂ and W ₃ are each a hydrogen atom, Fluorine atom, chlorine atom or CF ₃ ; X 1 represents CONR or SO ₂ NR, wherein R represents a hydrogen atom or an alkyl group of C _{1 to} C ₅ ; X2 represents a C ₁ to C ₁₀ alkylene group unsubstituted or substituted with OH or OCOCH ₃ ; n is an integer from 2 to 20; m represents 0 or 1. The polymer separation membrane according to claim 10, wherein the polymer separation membrane is made asymmetrically by mixing only one or two or more perfluoroalkyl-containing polymers. 12. The polymer separation membrane according to claim 11, wherein the number average molecular weight of the perfluoroalkyl-containing polymer is in the range of 5,000 to 100,000. The method of claim 10, wherein the polymer separator is a polymer commonly used as a separator material to the perfluoroalkyl-containing polymer, or an inorganic material selected from alumina and silica, or a metal powder selected from aluminum and iron is added. Polymer separation membrane, characterized in that prepared by asymmetrical. The polymer separator according to claim 10, wherein the polymer separator is a polymer or ceramic commonly used as a separator material, and a perfluoroalkyl-containing polymer is coated thereon to prepare a composite membrane structure. 15. The polymer separation membrane according to claim 13 or 14, wherein the number-average molecular weight of the perfluoroalkyl-containing polymer is in the range of 1,000 to 100,000. 11. The polymer separation membrane according to claim 10, wherein the polymer separation membrane is made of a flat plate, a tube type, a hollow fiber type, or a spiral wound type. The polymer separation membrane according to claim 10, wherein the perfluorinated alkyl-containing diamine represented by Chemical Formula 1 contains a diamine containing no fluorine within a range of less than 80% by weight. The method of claim 19, wherein the fluorine-free diamine is m-phenylenediamine, p-phenylenediamine, diaminobenzoic acid, diaminosulfonic acid, methylenedianiline, oxydianiline, 1,3, A polymer separation membrane, characterized in that one or two or more selected from 5-trimethyl-2,6-phenylenediamine and isopropylidene dianiline. The polymer separation membrane according to claim 10, wherein the perfluoroalkyl-containing polymer is a polyamide, a polyimide, a polyamide copolymer, a polyimide copolymer or a polyamide-imide copolymer represented by the following Chemical Formula 5a or 5b. . Formula 5a Formula 5b In the formula: R _f is as defined in claim 10, Ar is determined by a dicarboxylic acid derivative.