KR20050078747A - A nano composite typed hollow fiber membrane, and a process of preparing for the same - Google Patents

Abstract

The present invention relates to a nanocomposite hollow fiber membrane and a manufacturing method thereof, wherein the nanocomposite hollow fiber membrane of the present invention contains an inorganic substance in the hollow fiber membrane. In addition, the manufacturing method of the present invention is an inorganic material in the spinning dope when producing a hollow fiber membrane by spinning the spinning dope consisting of a hydrophobic polymer, an organic solvent and a hydrophilic compound and the internal coagulating solution in the air with a double tube nozzle It is characterized by the addition of. The present invention is particularly useful as a blood purification hollow fiber membrane is superior to the conventional hollow fiber membrane, and also useful as a microfiltration membrane or an ultrafiltration membrane due to its excellent physical properties.

Description

Nanocomposite hollow fiber membrane and its manufacturing method {A nano composite typed hollow fiber membrane, and a process of preparing for the same}

The present invention relates to a hollow fiber membrane excellent in blood compatibility and physical properties by forming a nanocomposite through the addition and dispersion of an inorganic material in the hollow fiber membrane and a method for producing the same.

Hollow fiber membranes, particularly hemodialysis membranes in direct contact with blood, require good blood compatibility.

As the material of the hollow fiber membrane for hemodialysis, cellulose-based polymers such as cellulose acetate, cellulose diacetate, cellulose triacetate, and the like, and synthetic polymers such as polysulfone, polyethersulfone, and polymethyl methacrylate are mainly used. Sulfonated hollow fiber membranes are known to exhibit good blood compatibility (J. Am. Soc. Nephrol. 1996; 7: 871-876).

In addition, U.S. Patent No. 4,906,375 discloses a method of preparing a hollow fiber membrane suitable for hemodialysis by adding polyvinylpyrrolidone to the preparation of a polysulfone hollow fiber membrane.

In addition, according to a study on the effect of polyvinylpyrrolidone on the blood compatibility (ASAIO Transactions 34 (3) 334-337, 1988), the blood compatibility is improved as the amount of polyvinylpyrrolidone remaining in the hollow fiber membrane increases. .

Japanese Laid-Open Patent Publication No. 1998-230148 discloses a method of crosslinking with gamma rays to increase the amount of polyvinylpyrrolidone remaining in the hollow fiber membranes.

Therefore, polysulfone shows the best blood compatibility among the materials of the blood purification membranes for hemodialysis in particular, and the polyvinylpyrrolidone component remaining in the hollow fiber membranes plays an important role.

However, if the amount of polyvinylpyrrolidone remaining in the hollow fiber membrane is high, polyvinylpyrrolidone is eluted from the hollow fiber membrane during hemodialysis, and these may accumulate in the blood and cause other side effects. Therefore, the use of polyvinylpyrrolidone to the extent that does not cause such side effects is required, and in the case of using an excessive amount of polyvinylpyrrolidone, another post-treatment method such as crosslinking should be added.

However, even the hollow fiber membrane thus prepared still has the disadvantage of administering a certain amount of antithrombotic heparin at the time of actual dialysis, thus improving blood compatibility of the hollow fiber membrane for hemodialysis, in particular for hemodialysis, is a very important task.

An object of the present invention is to produce a hollow fiber membrane having excellent physical properties and blood compatibility by preparing a nanocomposite hollow fiber membrane by adding and dispersing an inorganic substance inside the hollow fiber membrane.

Nanocomposite hollow fiber membranes of the present invention for achieving such a problem is characterized in that it contains an inorganic substance in the hollow fiber membrane.

Hereinafter, the present invention will be described in detail.

The present invention is to prepare a spinning dope by dissolving an organic clay in which a polymer resin, a polar polymer, a hydrophilic polymer and a hydrophilic group are introduced into an organic solvent; Spinning dope and internal coagulating liquid are spun into the air by using a conventional double tubular nozzle, and solidified in the external coagulating liquid to form a membrane structure and wound by successively washing with water and high temperature drying to prepare a nanocomposite hollow fiber membrane. .

Specifically, the polymer resin is dissolved in an organic solvent and polyvinylpyrrolidone and an inorganic substance are added to prepare a spinning dope. In addition to the spinning dope preparation, various additives are optionally added.

As the inorganic substance, organic clay into which hydrophilic groups such as -COOH group, -OH group, -SH group, or -NH ₂ group are introduced may be used. 0.01-5% by weight of inorganics are added to the total weight of the spin dope. If it is added less than 0.01% by weight, the improvement of physical properties and blood compatibility is insignificant. If it is added in excess of 5% by weight, particles in the spinning dope may be precipitated, causing cuts during spinning and uniformity of the hollow fiber membrane. have.

As the polymer resin used in the present invention, polysulfone resin, polyethersulfone resin, sulfonated polysulfone resin, polyvinylidene fluoride resin, polyacrylonitrile resin, polyimide resin, or the like may be used. -Methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide (DMF) and the like are used alone or as a mixed solution. It is preferable to use an inorganic salt, an alcohol compound, polyethylene glycol, polyvinyl alcohol, or the like as an additive to be selectively added.

The spinning dope is preferably about 1-30% by weight of an additive containing 10-50% by weight of polysulfone resin, 20-89% by weight of an organic solvent, 0.5-10% of an inorganic substance, and polyvinylpyrrolidone. However, the present invention does not limit the composition ratio of the spinning dope to this.

As the internal coagulating solution, a solution containing a glycol compound, a glycol compound, or a solution containing an organic solvent is used. It is preferable to use the mixed solution of diethylene glycol and water as a glycol compound used at the time of internal coagulating liquid composition. As the external coagulating solution, it is preferable to use water or a mixture of an organic solvent and water.

After the spinning dope is prepared into a hollow fiber membrane through a conventional wet-and-water spinning process, the content of the inorganic material contained in the final hollow fiber membrane is preferably 0.01 to 3% by weight, wherein the inorganic material is a nanocomposite evenly dispersed in the hollow fiber membrane To be formed, the performance of the hollow fiber membrane can be improved. In particular, the inorganic material is an organic clay in which hydrophilic groups such as -COOH, -OH, -SH, and -NH ₂ groups are introduced, which is suitable for improving blood compatibility of the hollow fiber membrane.

The nanocomposite hollow fiber membranes containing the organic clay thus prepared have a high water permeability at the same rejection rate by increasing the number of small micropores in addition to the hollow fiber membranes prepared under the same conditions.

In the case of nanocomposite hollow fiber membranes prepared by adding inorganic material to dope under the same manufacturing conditions, evenly dispersed inorganic materials in the solvent-non-solvent substitution process serve as a nucleus to promote the formation of more micropores.

In addition, in the case of using an organic clay having a hydrophilic group introduced as an inorganic material, the hydrophilicity of the polymer resin forming the hollow fiber membrane is permanently improved, thereby providing excellent permeability and fouling resistance. Therefore, the nanocomposite hollow fiber membranes of the present invention are very useful as hemodialysis hollow fiber membranes as well as microfiltration membranes or ultrafiltration membranes.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited only to the following examples.

Example 1

17% by weight of polysulfone resin, 9% by weight of polyvinylpyrrolidone, 9% by weight of polyethylene glycol, and 1% of organic clay were stirred and dissolved in 64% by weight of dimethylacetamide to prepare a transparent spinning stock solution. This spinning stock solution was discharged at a rate of 2.0 g / min from the annular slit mold having an outer diameter of 0.35 mm Φ and an inner diameter of 0.2 mm Φ injection hole diameter of 0.15 mm Φ, and at the same time, an 80% dimethyl acetylamide aqueous solution, 1.3 g / min Injected at a rate. After passing through the air gap of 20cm and spinning the hollow fiber with an external coagulation bath (water) of 45 ℃ solidified water washed and dried. The prepared hollow fiber membrane was bundled and dried to have a membrane area of 1.3 m 2, placed in a housing made of polycarbonate, and potted using a polyurethane adhesive to prepare a dialysis machine, and then sterilized with gamma rays. The hemocytometer change test results of the manufactured hemodialysis machine are shown in Table 1, and the test results of the complement (C3) and complement activation (C3a) changes are shown in Table 2.

Example 2

A hollow fiber membrane was manufactured under the same process and conditions as in Example 1, except that the content of the organic clay in the dope composition was changed to 0.5 wt%. The hemocytometer change test results of the manufactured hemodialysis machine are shown in Table 1, and the test results of the complement (C3) and complement activation (C3a) changes are shown in Table 2.

Example 3

A hollow fiber membrane was prepared under the same process and conditions as in Example 1 except that the content of the organic clay in the dope composition was changed to 5 wt%. The hemocytometer change test results of the manufactured hemodialysis machine are shown in Table 1, and the test results of the complement (C3) and complement activation (C3a) changes are shown in Table 2.

Comparative Example 1

A hollow fiber membrane was prepared under the same process and conditions as in Example 1 except that the organic dope was not included in the dope composition. The hemocytometer change test results of the manufactured hemodialysis machine are shown in Table 1, and the test results of the complement (C3) and complement activation (C3a) changes are shown in Table 2.

The blood compatibility of the prepared hemodialyzer was evaluated as follows.

1) Device used: hemodialysis apparatus (Baxter 1550)

2) Blood used: Human whole blood (5 days after collection)

3) Experiment Method

① Connect the hemodialysis machine to the device with a blood line.

② Remove 0.9% physiological saline solution (1000ml) by flowing it into the hemodialysis membrane using a pump (use 500ml / EA). Do not use dialysis solution.

③ The blood in a 320ml transfusion bag is pumped into the hemodialysis membrane.

④ Blood Line When all physiological saline solution used for cleaning is discharged and blood flows out, connect Blood Line outlet to Blood Line inlet located in front of hemodialysis machine.

⑤ Collect blood sample in CBC tube (containing EDTA) and Plain tube at 5 and 15 minutes while continuously circulating blood remaining in Blood Line and Hemodialyzer at 200ml / min flow rate. Blood before permeation of the hemodialyzer is taken as the reference (0 min).

⑥ Blood collected in CBC tube is analyzed by the Coulter Towner (Coulter Counter) in the Clinical Pathology Department, blood collected in the plain tube (Plain tube) is centrifuged to collect only the plasma components and refrigerated storage Complement (C3) and complement activation (C3a) are measured.

※ During the blood circulation, the water is permeated through the dialysis membrane, so the blood is slightly concentrated and the remaining blood in the transfusion bag is continuously supplied. Therefore, the concentration of concentration should be corrected by the change of hematocrit of blood.

Blood Cell Change Test Result (Unit:%) Item Example 1 Example 2 Example 3 Comparative Example 1 Red blood cells  0 min 100.0 100.0 100.0 100.0  5 minutes 100.5 100.3 100.1 100.6 15 minutes 100.7 101.4 100.5 101.1 leukocyte  0 min 100.0 100.0 100.0 100.0  5 minutes 99.5 99.2 99.4 99.0 15 minutes 94.0 92.3 95.5 90.6 Platelets  0 min 100.0 100.0 100.0 100.0  5 minutes 90.3 82.5 90.0 59.2 15 minutes 81.5 72.3 87.0 42.4

The values in Table 1 show the rate of increase and decrease of the measured values at 5 and 10 minutes after hemodialysis, based on the initial value of hemodialysis (100%).

In the case of the hollow fiber membrane of Examples 1 to 3 to which the organic clay was added, it was confirmed that the blood compatibility was greatly improved when the amount of platelet decrease was small.

Complement (C3) and Complement Activation (C3a) Change Test Results (Unit:%) Item Example 1 Example 2 Example 3 Comparative Example 1 C3  0 min 100.0 100.0 100.0 100.0  5 minutes 103.2 105.3 100.4 121.2 15 minutes 105.3 115.5 100.8 136.0 C3a  0 min 100.0 100.0 100.0 100.0  5 minutes 120.2 130.0 115.2 146.8 15 minutes 140.3 160.5 150.2 304.0

The values in Table 2 show the rate of increase and decrease of the measured values at 5 and 10 minutes after hemodialysis, based on the initial value of hemodialysis (100%).

In the case of the hollow fiber membrane of Examples 1 to 3 to which the organic clay was added, it was confirmed that the blood compatibility was greatly improved when the degree of complement activation was small.

The hollow fiber membrane of the present invention is a nanocomposite hollow fiber membrane in which organic clay is evenly dispersed compared to the conventional hollow fiber membrane, and thus the blood compatibility is significantly improved to reduce side effects such as blood coagulation when used as a hemodialysis membrane. In addition, it is also useful as a microfiltration membrane or an ultrafiltration membrane due to its excellent water permeability.

Claims (7)

A hollow fiber membrane, wherein the nanocomposite hollow fiber membrane contains an inorganic substance in the hollow fiber membrane. The nanocomposite hollow fiber membrane according to claim 1, wherein the content of the inorganic material is 0.01-3% by weight based on the total weight of the hollow fiber membrane. The nanocomposite hollow fiber membrane according to claim 1, wherein the inorganic material is an organic clay having a hydrophilic group introduced therein. The nanocomposite hollow fiber membrane according to claim 3, wherein the hydrophilic group is a -COOH group, -OH group, -SH group, or -NH ₂ group. In the manufacturing of the hollow fiber membrane by spinning the spinning dope and the internal coagulating solution consisting of a hydrophobic polymer, an organic solvent and a hydrophilic compound into the air with a double tubular nozzle and then coagulating with an external coagulating liquid, inorganic substances are added to the spinning dope. Method for producing a nanocomposite hollow fiber membrane. The method for producing a nanocomposite hollow fiber membrane according to claim 5, wherein the inorganic material is added in an amount of 0.01-5% by weight based on the total weight of the spinning dope. The method of manufacturing a nanocomposite hollow fiber membrane according to claim 5, wherein the inorganic material is an organic clay having a hydrophilic group introduced therein.