JP2003290339A - Method for producing hydrophilized aromatic polymer molded article - Google Patents

Abstract

(57) [Problem] To provide a molded article made of an aromatic resin having high hydrophilicity by a simple production method. A method for producing a hydrophilicized aromatic polymer molded body, comprising irradiating a polymer molded body having a surface contact angle of 65 ° or more with radiation in water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a hydrophilized aromatic polymer molding. In particular, it is useful for optical applications, printing applications and biomaterial applications that require hydrophilicity on the surface.

[0002]

2. Description of the Related Art Aromatic polymers such as polysulfones are excellent materials in terms of heat resistance, chemical resistance and moldability, and are used in a wide variety of fields. However, since these materials are hydrophobic, there are problems that contamination easily occurs and that they have low affinity with a coating material having a high affinity for a hydrophilic substance.

In order to improve them, various investigations have been made. For example, by adding an appropriate amount of a hydrophilic polymer, polyvinylpyrrolidone, hydrophilicity is imparted to polysulfone, and thereby, contamination of the membrane is prevented. The suppression method is disclosed in JP-A-61-9380, JP-B-2-18695, JP-A-61-238834, and by blending a graft or block copolymer composed of a hydrophilic polymer segment and a hydrophobic segment, a polysulfone-based compound. A method of imparting hydrophilicity to a membrane and thereby suppressing fouling of the membrane is disclosed in JP-A-62-201203 and JP-A-63.
No. 7-7941, JP-A-2-2862, and JP-A-55-36296 disclose that a polysulfone hollow fiber membrane is soaked in concentrated sulfuric acid to be sulfonated. In addition, the radicals generated by methods such as irradiating the polymer surface with radiation, ultraviolet rays, plasma treatment by arc, direct current glow, high frequency wave, microwave, corona discharge, UV-ozone treatment, etc. are started. As a point, a method in which a radical polymerizable monomer is allowed to act on this to form a graft polymerization layer on the surface is also widely used. For example, A. Henglein, Angew. Chem., 70, 461 (195
In 5), radiation-induced graft polymerization is also described in Y. Ogi.
wara, et. al., Poym. Sci., Polym Letter Ed., 1
9, 457 (1981), a method of graft-polymerizing methyl methacrylate or acrylic acid using an aqueous polyvinyl acetate solution on a polypropylene surface or a polyethylene surface is proposed. Raft; engineering material, 3
1, 62 (1983), a graft polymerization of acrylamide onto a polyethylene surface using argon plasma is proposed. Further, surface hydrolysis treatment with alkali is also performed, and a method of performing alkali treatment on cellulose has been disclosed (JP-A-56-07643).
4, JP-A-57-036131).

However, these hydrophilizing materials require a large amount of hydrophilic polymer in addition to the aromatic polymer, the process of hydrophilizing is complicated, and the obtained material is not transparent. There were drawbacks such as.

[0005]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above-mentioned drawbacks of the prior art, and an object thereof is to provide a molded product made of an aromatic resin having high hydrophilicity by a simple method. At the same time, it is also an object to provide a transparent molded body having hydrophilicity and a hydrophilic membrane having selective permeability.

[0006]

In order to achieve the above object, the present invention has the following constitution. (1) A method for producing a hydrophilized aromatic polymer molded product, which comprises irradiating a polymer molded product having a surface contact angle of 65 degrees or more with water. (2) The method for producing a hydrophilized aromatic polymer molding according to (1), wherein the aromatic polymer is a polysulfone-based polymer. (3) The method for producing a hydrophilized aromatic polymer molding according to (1) or (2), wherein the hydrophilized aromatic polymer molding is a transparent body. (4) The method for producing a hydrophilized aromatic polymer molding according to (1) or (2), wherein the hydrophilized aromatic polymer molding is a permselective membrane. (1) A method for producing a hydrophilized aromatic polymer molded product, which comprises irradiating a polymer molded product having a surface contact angle of 65 degrees or more with water. (2) The method for producing a hydrophilized aromatic polymer molding according to (1), wherein the aromatic polymer is a polysulfone-based polymer. (3) The method for producing a hydrophilized aromatic polymer molded article according to (1) or (2), wherein the molded article is a transparent body. (4) The method for producing a hydrophilized aromatic polymer molded article according to (1) or (2), wherein the molded article is a permselective membrane.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The aromatic polymer referred to in the present invention is
A polymer having hydrophobicity, which has been widely applied in various fields due to its good mechanical properties and heat resistance, poly (p-phenylene ether sulfone):-{(p-C6
H4) -SO2- (p-C6 H4) -O-} n- and Udel polysulfone :-( p-C6 H4) -SO2-
(P-C6 H4) -O- (p-C6 H4) -C (CH3
) 2- (p-C6 H4) -O} n-, as well as-(p-
C6 H4) -SO2-(p-C6 H4) -O- (p-C
6 H4) -O} n-,-{(p-C6 H4) -SO2-
(P-C6 H4) -S- (p-C6 H4) -O} n-,
-{(P-C6 H4) -SO2-(p-C6 H4) -C
(CF3)-(p-C6 H4) -O- (p-C6 H4)
A polysulfone-based polymer having a structure such as -O} n-,
Polymers such as polyimide, polyetherimide, aromatic nylon, aramid, polyamideimide, polyarylate, polyetherketone, polyetheretherketone, polyphenylene sulfide, polyphenylene oxide, polycarbonate and polyester can be used,
Hydrogen substituted in the polymer main chain with a halogen compound, a hydrocarbon or the like can be used, but is not limited thereto.

The surface contact angle in the present invention is the angle formed by the liquid surface and the solid surface at the place where the free surface of the stationary liquid contacts the solid wall, and the film is immersed in water to introduce bubbles into the lower surface of the film. Then, the contact angle can be measured from the contact angle between the film surface and the bubbles. A polymer molded product having a surface contact angle of 65 degrees or more is a molded product in which an aromatic polymer or a small amount of a hydrophilic polymer is mixed, and the hydrophilic polymer here is polyvinylpyrrolidone or polyethylene glycol. Water-soluble polymers such as, but not limited to, polyethyleneimine, polyacrylamide, polyvinyl alcohol, polyallylamine, polyacrylic acid, and polyvinyl sulfuric acid can be used. The surface contact angle in the present invention is 65.
The polymer molded body having a temperature of not less than the above can be prepared by dissolving an aromatic polymer in a solvent to form a film or a hollow fiber, or by melting at a high temperature, molding, and then cooling, but not limited to this method.

The hydrophilicity in the present invention means that the surface contact angle is less than 65 degrees, more preferably less than 60 degrees, and even more preferably less than 55 degrees. Further, making hydrophilic in the present invention means converting a substance having a surface contact angle of 65 degrees or more into a substance having a surface contact angle of less than 65 degrees.

As an example of forming a molded body, a case where a film-shaped molded body is prepared by dissolving polysulfone in a solvent will be described. In selecting the solvent, a good solvent for the polysulfone-based resin and the hydrophilic polymer may be used, and specifically, dimethylacetamide, dimethylformamide, dimethylsulfoxide, acetone, acetaldehyde, 2-methylpyrrolidone, etc. may be used. However, dimethylacetamide is preferable in terms of danger, safety, and toxicity, though not limited thereto. The method for forming the transparent film is as follows. First, gently spread an appropriate amount while spreading the film-forming solution laterally on the front edge of the glass plate, and pull the applicator that can keep the cast thickness constant on the glass plate at a constant speed to keep the cast liquid even. Use the spreading method. After the film is formed in this manner, it is washed with water and subjected to a predetermined peeling step, and then dried to obtain a film.

The transparent material means a material having a light transmittance of 80% or more, which is measured by using an SM color computer SM-7-CH manufactured by Suga Test Instruments Co., Ltd., more preferably 85% or more, and more preferably 88%. The above is even more preferable.

[0012] The permselective membrane may be any membrane having a selective permeability in the separation operation, and a low molecular weight substance such as a hollow fiber membrane for artificial kidney or an RO membrane for seawater desalination is selected. However, the present invention is not limited to these. The membrane of the present invention is an aggregate of aggregated particles and has a dense layer and a supporting layer other than the dense layer. The dense layer is a part that determines the permeation performance, and an important factor is the size of the aggregated particles forming the dense layer. Generally, the smaller the diameter of the agglomerated particles forming the dense layer and the more they aggregate, the lower the permeation performance of the membrane. On the other hand, if it is too large, albumin, which is a useful plasma protein, will permeate, which is not preferable as a blood permeable membrane.

The hydrophilized aromatic polymer molding can be obtained by irradiating a polymer molding having a surface contact angle of 65 degrees or more, which is brought into contact with water, with radiation. Examples of the state of being brought into contact with water include a state in which a molded body is put in water, and a state in which water is impregnated by impregnating a polymer porous membrane with water. When treating a hollow porous body such as an artificial kidney that is internally contained, by impregnating the hollow porous body with water and irradiating the case with radiation, at least contacting with water The existing part can be made hydrophilic.

When the hydrophilized aromatic polymer molding is a transparent material, a polymer molding having a surface contact angle of 65 degrees or more, which is a transparent material, is irradiated with radiation while being in contact with water. In order to obtain a hydrophilized aromatic polymer molding which is a permselective membrane,
It can be prepared by irradiating with radiation a polymer molded product having a surface contact angle of 65 degrees or more and having selective permeability in contact with water.

Irradiation with radiation may generate oxygen radicals from dissolved oxygen in water, and non-specific reactions may occur on the membrane surface. In order to prevent them, degassed water is preferably used. Deaerated water refers to a state in which the oxygen concentration measured by a commercially available oxygen concentration meter or the like is less than 0.2%, and more preferably less than 0.1%.

Radiation may be particle beams or electromagnetic waves, and γ rays, electron beams and the like are preferable, but not limited to these, because of their permeability and ease of crosslinking. The radiation dose is preferably 1 kGy or more, more preferably 5 kGy, particularly preferably 15 kGy or more. This is because a certain amount of energy or more is required to make the surface hydrophilic. When used as a medical material, sterilization can be performed simultaneously. If too much radiation is applied, the material may be deteriorated, and a transparent molded body may be colored. The upper limit of the irradiation dose may be selected within a range where these disadvantages do not occur, but usually 100 kGy
And preferably 50 kGy or less. The irradiation amount is measured by attaching a sheet for measuring the irradiation amount to the surface of the container containing the irradiation object. In addition,
If the measurement points differ depending on the location, measure at multiple points and take the average value.

The hydrophilic aromatic polymer molding obtained by the present invention is, for example, an optical material, a recording material, a protective material,
It is suitable for use in a wide range of fields such as anti-fog materials and medical materials.

The present invention will be described below with reference to examples.
The invention is not limited by these examples.

[0019]

EXAMPLES The present invention will now be described based on examples.

The measuring method used is as follows. (1) Measurement of contact angle It was measured using a contact angle meter CA-D manufactured by Kyowa Interface Science Co., Ltd. The measurement was performed in a room where the room temperature was adjusted to 25 degrees. (2) A platelet-adhesive film-like molded body is placed in a flat plate shape on the bottom of a cylindrical tube made of polystyrene having a diameter of 18 mm and filled with physiological saline. Blood obtained by mixing 3.2% trisodium citrate dihydrate aqueous solution and rabbit fresh blood at a volume ratio of 1: 9 was adjusted to a platelet count of 20 × 10 ⁻⁶ / ml, and platelet-rich plasma (PR
After adjusting to P) and discarding the prepared physiological saline in the cylindrical tube, add 1.0 ml of PRP and shake at 37 ° C. for 1 hour. Then, it was washed three times with physiological saline, the blood component was fixed with a 3% glutaraldehyde aqueous solution, washed with distilled water, and then dried. The inner surface of this hollow fiber membrane was observed with a scanning electron microscope to count the number of attached platelets in an area of 1.12 × 10 ³ μm ² . It can be said that the smaller the number of attached platelets, the better the adhesion resistance of the material.

In the following examples, "part" means "% by weight".
Means (3) Method of measuring light transmittance SM color computer SM-7- manufactured by Suga Test Instruments Co., Ltd.
It was measured using CH. The measurement was performed in a room where the room temperature was adjusted to 25 degrees. Example 1 Polysulfone (Udel-P3500 manufactured by Amoco) 10
90 parts of dimethylacetamide was added and dissolved at room temperature to obtain a film-forming solution. This solution was cast to a thickness of 203 μm on a glass plate whose temperature was controlled at 100 ° C., left for 5 minutes and then immersed in a water bath to obtain a transparent film. The obtained film had a contact angle of 82 degrees and a light transmittance of 89.16. This film was placed in a glass sample bottle containing 50 ml of degassed water and irradiated with 28 kGy of γ rays. The contact angle of the film after irradiation was 42 degrees, which was remarkably improved in hydrophilicity and the light transmittance was 88.45. The number of adhered platelets was 60 before γ-ray irradiation, whereas it was 20 in the film after γ-ray irradiation, which was a marked decrease.

[0022]

INDUSTRIAL APPLICABILITY As described above, the method for producing a hydrophilized aromatic polymer molded product according to the present invention can provide a hydrophilized aromatic polymer molded product in which hydrophilicity is imparted to the film surface. The provided molded product is expected to be used in a wide range of fields representing optical materials, recording materials, protective materials, anti-fogging materials, medical materials and the like. Particularly, the hydrophilized aromatic polymer molding provided by the manufacturing method of claim 3 has excellent transparency and can be suitably used for an optical material, and is provided by the manufacturing method of claim 4. The hydrophilized aromatic polymer molded product can be suitably used as a hollow fiber membrane for medical materials, particularly artificial kidneys.

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Claims (4)

[Claims] 1. A method for producing a hydrophilized aromatic polymer molded product, which comprises irradiating a polymer molded product having a surface contact angle of 65 degrees or more with water in water. 2. The method for producing a hydrophilized aromatic polymer molding according to claim 1, wherein the aromatic polymer is a polysulfone-based polymer. 3. The method for producing a hydrophilized aromatic polymer molding according to claim 1, wherein the hydrophilized aromatic polymer molding is a transparent body. 4. The method for producing a hydrophilicized aromatic polymer molded product according to claim 1, wherein the hydrophilicized aromatic polymer molded product is a permselective membrane.