JPH07138393A - Surface modification of polymer molding - Google Patents

Abstract

PURPOSE:To provide a modification process wherein a specified additives is used when the surface modification of a polymer molding is performed by introducing graft chains into the surface of the molding by irradiation and whereby more functional groups can be efficiently and stably introduced into any moldings. CONSTITUTION:An example of the polymer molding is a nonwoven fabric of polyethylene terephthalate. Examples of the substances to be grafted include substances (e.g. polyacrylic acid) having at least one functional group of at least one kind selected from among carboxyl groups, amino groups, imino groups, sulfonic groups, hydroxyl groups, epoxy groups, aldehyde groups, acyl groups and haloacyl groups in the molecule and having a molecular weight of 40-40000. Examples of the additives include polyalcohols (e.g. ethylene glycol), dehydrative condensates thereof and polyunsaturated substances (e.g. triethylene glycol diacrylate). These compounds can dissolve the substance to be grafted, and do not boil and kept flowable in a range from room temperature to 120 deg.C at atmospheric pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface modification method for polymer moldings by radiation graft polymerization. More specifically, the present invention relates to a method for modifying a surface of a polymer molded body, which comprises introducing a graft chain onto the surface of the polymer molded body by irradiation of radiation and adding a specific additive when modifying the surface. It is a thing.

In the present invention, the polymer molding to be modified is called a base material, and the substance introduced into the base material by radiation graft polymerization to form a graft chain is called an introduction compound.

[0003]

2. Description of the Related Art The most reliable method for modifying a polymer material is that the modified properties are easily retained by a chemical reaction. Starting with the use of polystyrene as the base material, ion-exchange resins with ionic substituents, fibers with functional groups for the purpose of improving affinity with dyes, etc. I have no time to enumerate.

In this method, a polymer material serving as a base material is chemically treated and modified in advance, and the modified material is molded to obtain a desired material. To provide a reforming reaction. In the former case, the reforming reaction can be carried out in a solution or dope state, so that the reaction efficiency can be increased and a relatively homogeneous material can be obtained. However, when the molded product is, for example, porous beads, it is necessary to establish not only a technique for modifying a polymer material but also a technique for manufacturing a molded product, and to establish a consistent technique for modification and three-dimensional molding.

On the other hand, in the latter case, it is necessary to properly select reaction conditions, reaction solvents, etc. that do not destroy the shape of the molded body, so that the chemical reactions actually applicable are naturally limited. However, since reforming is performed using a preformed base material, it is possible to separate the three-dimensional molding technology from the modification technology, and in some cases it is possible to use a commercially available polymer molding as the base material. It has the advantage that it can be done. In addition, this method can modify only the surface of the molded body. Although depending on the usage method, this point may be advantageous for achieving two conflicting properties such as compatibility between strength and function. Considering these advantages, it can be said that the method of introducing a functional group after molding has a wider range of application as far as technically possible.

The major advantage of reforming by chemical reaction is that it is stable, but on the other hand, handling is complicated because the reforming operation is troublesome, the equipment is large, and the conditions are difficult to set. There is a disadvantage that there is. Also, since it is necessary to select an appropriate reaction according to the structure of the base polymer, and to search for conditions suitable for each,
Application beyond the material is difficult. Furthermore, it is extremely difficult to modify chemically stable compounds such as polyethylene by this method.

The method using a polymer blend can overcome such disadvantages and is very easy to handle. This method basically only mixes,
It is not necessary to carry out operations such as setting conditions of the solvent and reaction temperature, refining the solvent, washing the product, etc., which must be taken into consideration during the chemical reaction. Therefore, it can be said that this is an extremely advantageous method in terms of preparation of the modifying material.

However, according to this method of modifying with a plasticizer, a stabilizer and other additives, these additives may be eluted depending on the application and the properties of the material may be changed with time, or the elution may occur. Various inconveniences may occur due to the influence of the object. Also, since additives are mixed, it is necessary to perform modification before molding, and as a result, the entire polymer material is modified by this method, resulting in film, fiber, beads, etc. It is difficult to modify only the surface of the molded body.

Further, as a post-treatment of the polymer material, there is a method called coating. Since this method is also not a chemical modification, it is not necessary to examine the reaction solvent, reaction conditions, etc. and set appropriately, and it can be carried out relatively easily. Moreover, unlike the case of blending,
It has the advantage that a function can be added to the surface of the material after molding. However, since this method relies on the physical affinity between the material and the coating agent, the modified layer on the surface may peel off during use.

Another effective method for modifying the polymer material is a radiation graft polymerization method. This method is a method of irradiating with high-energy radiation to generate radicals or ions on the surface of the base material and introducing a graft chain, and can also be applied to a chemically stable and inert polymer such as polyethylene.

In this method, detailed examination and setting of reaction conditions such as chemical reaction modification can be omitted to some extent, and a function can be imparted to the surface of the molded polymer material. Further, unlike the case of coating, the radicals and ions generated on the surface of the base material are used for modification, and therefore the possibility of peeling is expected to be extremely small.

In the case where the modification is carried out by this method, it is a general technique to coat the surface of the substrate with the introduced compound and irradiate it with radiation. At this time, it is more preferable to dissolve the introduced compound in a suitable volatile solvent and apply it to the substrate, and then to evaporate and remove the volatile solvent, because uniform and even application is possible. Use of a solvent may be indispensable, especially when the introduced compound is a solid or a viscous fluid.

Various compounds can be introduced by the radiation graft polymerization method, but the most efficient one is a compound having a structure having a carbon-carbon unsaturated bond in the molecule. Radicals and ions generated on the surface of the base material by the irradiation of radiation act as an initiator to extend the graft chain of the introduced compound from the surface of the base material.

Further, compounds such as polyols, which easily generate radicals by obtaining energy, are relatively easily introduced. Further, a polyvinyl compound having an electron-withdrawing substituent such as polyacrylonitrile or polymethyl acrylate can be introduced because the hydrogen at the α-position is easily radically desorbed.

That is, any compound having an uneven electron distribution may be introduced into the polymer molded body as a base material by radiation graft polymerization.
However, in practice, there are strictly compounds that can be easily introduced and compounds that are not.

Our interest is not solely the ease of introduction into the substrate, but the function exerted by the introduction. That is,
The first purpose is to provide a function, and the introduction thereof is not always easy to implement. Introducing a specific compound into a substrate as a graft chain requires some means. However, in the method of introducing a graft chain into a polymer molding by irradiation with radiation, an effective method for improving the introduction efficiency is not well known.

A method generally used as a means for improving the efficiency of immobilizing the introduced compound on the substrate is a method using an anchoring agent. This method is well compatible with the base material, and a compound that easily generates radicals or ions under high energy is applied to the base material as an anchoring agent, and the introduction compound is applied to the pretreated base material, This is a method of grafting. However, although this anchor agent bridges the base material and the introduced compound, it does not necessarily form a chemical bond of the base material-anchor agent-introduced compound. Therefore, in the case of a material such as a medical material that has strict examination criteria, there may be a situation in which the amount of elution is too large to practically use it.

[0018]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art, and a surface-modified polymer molding in which a graft chain is introduced onto the surface of a substrate with high efficiency and a surface modification of the polymer molding. It was an attempt to provide the law.

[0019]

Means for Solving the Problems The method for modifying the surface of a polymer molded body of the present invention is capable of dissolving a compound introduced when a graft chain is introduced onto the surface of the polymer molded body by irradiation with an atmospheric pressure. It is characterized by adding an additive capable of maintaining fluidity without boiling at a room temperature to 120 ° C.

In the surface-modified polymer molding and the method for modifying the surface of the polymer molding of the present invention, the radiation to be applied when the graft chain is introduced into the surface of the polymer molding is not particularly limited, but among them, the electron beam is used. Is preferred.

The method for modifying the surface of a polymer molding of the present invention is as follows:
The compound introduced is a carboxyl group, an amino group, an imino group,
It has at least one functional group of at least one selected from the group consisting of a sulfonic acid group, a hydroxyl group, an epoxy ring, an aldehyde group, an acyl group and a haloacyl group, and has a molecular weight of 40-
It is characterized in that it is a substance such as 40,000.

The method for modifying the surface of a polymer molding of the present invention is
A particularly preferred additive is a polyhydric alcohol or a dehydration condensation product of a polyhydric alcohol.

The method for modifying the surface of a polymer molding of the present invention is
Another particularly preferred example is characterized in that the additive is a substance having a structure having a plurality of double bonds in the molecule.

The introduced compound in the present invention is as described above, and specifically, acrylic acid (hereinafter abbreviated as AA), methacrylic acid (hereinafter abbreviated as MA), polyacrylic acid (hereinafter abbreviated as PAA), polymethacryl Carboxyl group-containing compounds such as acids (hereinafter abbreviated as PMA); ethylenediamine (hereinafter abbreviated as en), diethylenetriamine, triethylenetetramine, allylamine, polyethyleneimine (hereinafter abbreviated as PEI), amino group-containing compounds such as polyallylamine; styrene sulfone Sulfonic acid group-containing compounds such as acids and polystyrene sulfonic acids; hydroxyl group-containing compounds such as vinyl alcohol, polyvinyl alcohol (hereinafter abbreviated as PVA); epoxy ring-containing compounds such as vinyl glycidyl ether; aldehyde group-containing compounds such as acrolein; Acyl group-containing compounds such as vinyl (hereinafter abbreviated as PVAc); haloacyl compounds such as polybromovinyl acetate (hereinafter abbreviated as PVBrAc); polyethylene glycol (hereinafter abbreviated as PEO acid) having a carboxyl group introduced at the terminal, amino at the terminal Examples include polyethylene glycol having a group introduced (hereinafter abbreviated as PEO amine), polyethylene glycol having a glycidyl group introduced at a terminal (hereinafter abbreviated as PEO epoxy), polyethylene glycol having an aldehyde group introduced at a terminal (hereinafter abbreviated as PEO aldehyde), and the like. To be

When a compound containing a carboxyl group or an amino group is introduced among these compounds, an electric charge is imparted to the surface of the base material. Such a technique is a method for synthesizing an ion exchange material, a method for synthesizing an enzyme immobilization material by ionic bond,
It can be used as an antistatic method for various polymer moldings and as a technique for improving the dyeability of synthetic fibers. Also, a carboxyl group,
A molded product having a surface hydrophilized by introducing an amino group or a hydroxyl group-containing compound may be used as a medical material having excellent blood compatibility. Carboxyl group, amino group, epoxy ring, aldehyde group, acyl group, and haloacyl group are active functional groups that are often used for enzyme immobilization.
There is a possibility that a physiologically active substance such as an antibody, an antigen, a cell, or a protein having other functions can be immobilized on the surface of a polymer molded body by covalent bonding.

The method of the present invention is particularly excellent as a method for modifying the surface of non-woven fabrics, hollow fibers, porous polymer beads, etc., and is most suitable for use as a medical material based on these materials. The term "medical materials" as used herein refers to artificial dialysis membranes and blood cell separation materials that have hydrophilic groups and are excellent in blood compatibility, blood purification materials that have functional groups that have a specific affinity with pathogenic substances, and An example is an immunoadsorbent in which a physiologically active substance is immobilized after the introduction of the functional group of 1.

Specific examples of the polyhydric alcohol used as an additive in the present invention and its dehydration condensate include ethylene glycol, propylene glycol, tetramethylene glycol, 1,6-hexanediol, glycerin; diethylene glycol and triethylene. Glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyglycerin, etc. are exemplified, but the molecular weight of the dehydrated condensate is appropriately selected, and it does not boil at room temperature to 120 ° C. under atmospheric pressure and has fluidity. It is necessary to hold.

Used as an additive in the present invention,
Examples of substances having a structure having a plurality of unsaturated bonds in the molecule include ethylene glycol diacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, ethylene glycol divinyl ether, polyethylene glycol divinyl ether, ethylene glycol diallyl ether, polyethylene glycol diallyl ether. , Ethylene glycol diacetenyl ether, ethylene glycol dipropargyl ether, etc. are exemplified. In the case of a polymer derivative, the molecular weight is appropriately selected so that it does not boil at room temperature to 120 ° C. under atmospheric pressure and has fluidity. It is necessary to hold.

The effects of these additives are roughly classified into two types. The first is the effect of promoting contact between the introduced compound and the substrate. When the introduced compound has sufficient fluidity around room temperature, it is in sufficient contact with the substrate, and it is expected that grafting by electron beam irradiation will proceed relatively easily, but it will precipitate as a solid. When such a compound is used as the introduction compound, the contact area with the substrate is limited, which may reduce the graft efficiency.
Further, when the introduced compound becomes a solid, the contact with the base material becomes uneven, and microscopically, a portion where the graft chain is introduced and a portion where the graft chain is not introduced occur.

When the additive can dissolve the introduced compound, does not boil at room temperature to 120 ° C. under atmospheric pressure, and maintains fluidity, the introduced compound and the substrate are uniformly mixed. You can expect to contact them efficiently.
Therefore, there is a high possibility that the grafting on the substrate will proceed efficiently and uniformly.

The second effect that can be expected is that the additive functions as a crosslinking agent. The additive used in the present invention is a polyhydric alcohol, a polyhydric alcohol dehydration condensate, or a substance having a plurality of multiple bonds in the molecule. All of these compounds easily generate chemically active species such as radicals by obtaining energy by an electron beam or the like. Therefore, it is expected that it will function effectively as a cross-linking agent for the base material and the introduced compound by irradiation with radiation.

These additives may be used alone or, if necessary, as a mixture of two or more kinds.
In addition to these additives, at room temperature to 120
The use of a cross-linking agent that does not boil at 0 ° C. and that does not satisfy the requirement of maintaining fluidity is not limited in the present invention.

The substrate used in the present invention may be in any form including particles, fibers, films and the like. Further, the use of the surface-modified polymer molding obtained by the present invention is not limited by the present invention.

The present invention will be described below with reference to examples. Example 1 A nonwoven fabric made of polyethylene terephthalate (hereinafter abbreviated as PET) having a fiber diameter of 3.5 μm and a basis weight of 45 g / m ² was cut into 15 cm × 12 cm (weight: about 810).
mg). This PET non-woven fabric was thoroughly washed with acetone prior to modification. PAA15 with a molecular weight of 4000
g, triethylene glycol diacrylate (hereinafter EG
_3- A) 5 g, glycerin 5 g, methanol 1 l
And then the PET non-woven fabric was dipped in this solution to apply PAA and additives. After sufficiently drying (60 ° C., 6 hours), an electron beam (hereinafter abbreviated as EB) was irradiated at a dose of 5 Mrad on one surface to graft PAA onto the surface of the PET nonwoven fabric.

The surface-modified PET non-woven fabric obtained by the above operation was thoroughly washed with running deionized water. Then, it was immersed in boiling ion-exchanged water and washed by boiling for 20 minutes. After repeating this boiling cleaning three times, the non-woven fabric was immersed in methanol, the container was immersed in the ultrasonic cleaner for 15 minutes, and the ultrasonic cleaning was repeated three times, and then sufficiently dried in a vacuum dryer (60). C, 18 hours). Thus PAA introduced PET
Nonwoven PET-PAA-1 was obtained.

Quantification of the content of carboxyl groups introduced into PET-PAA-1 and eluate test were carried out. The results are shown in Table 1. In addition, each test method is as shown below.

[0037]

[Table 1] In the above table, -CHOOH: carboxyl group -NH ₂ etc .: primary, secondary, tertiary amino groups and imino groups pH: pH (difference between the blank) UV: UV absorption spectrum KMnO _4: Over Potassium manganate consumption (difference from blank) Residue: Evaporation residue IN: Within the evaluation standard range OUT: Exceeds the evaluation standard range. (1) Quantification of carboxyl group About 0.2 g of finely chopped PET-PAA-1 was accurately weighed (this amount is defined as W ₁ g), and 10 ml of 0.1N sodium hydroxide (titer was F ₁ ). ) Was added and the suspension was diluted with dioxane / water (1/1 volume ratio) to a total volume of about 60 ml. After stirring this for about 30 minutes, it was titrated with 0.1 hydrochloric acid aqueous solution (titer is F ₁ ′) using an automatic titrator (COMITITE 101 manufactured by Hiranuma Sangyo). The amount of 0.1N hydrochloric acid aqueous solution required for neutralization was V ₁
In ml, the carboxyl group content (X ₁ meq / g) of PET-PAA-1 was obtained by the following formula. W ₁ × X ₁ + 0.1 × F ₁ '× V ₁ = 0.1 × F ₁ × 10

(2) Eluate test 1.0 g of PET-PAA-1 was accurately weighed and about 2 cm
Cut it into a size of 2 cm and put it in a container.
ml was added. After heating at 70 ° C for 1 hour and cooling, PET
-PAA-1 was removed and the remaining liquid was used as the test liquid. Further, distilled water which was similarly heated without adding PET-PAA-1 was used as a blank. The following five items were examined in the eluate test. Appearance The standard was passed when almost no color and no foreign matter was visually observed. pH 1.0 g of potassium chloride was dissolved in distilled water to make 1 l (hereinafter abbreviated as KCl solution). Take 20 ml of test liquid and
A Cl solution (1.0 ml) was added and the pH was measured with a pH meter (F-12 manufactured by Horiba Ltd.). The pH of the blank was measured in the same manner, and the difference from the test solution was recorded. When this value was 1.5 or less, it was regarded as the standard passage. UV absorption spectrum 200 nm-400 n of the test solution using the blank as a control
Absorbance of m is spectrophotometer (Hitachi U-3210)
The maximum absorbance from 220 nm to 350 nm was recorded. When this value was 0.1 or less, it was regarded as the standard passage.

Potassium permanganate reducing substance Test liquid (10.0 ml) was placed in a ground-in stopper Erlenmeyer flask and adjusted to 0.0
20.0 ml of 1N potassium permanganate aqueous solution and 1.0 ml of dilute sulfuric acid were added, and the mixture was boiled for 3 minutes. After cooling, 0.10 g of potassium iodide was added thereto, the mixture was tightly capped, shaken and left for 10 minutes, and then titrated with an aqueous 0.01 N sodium thiosulfate solution (indicator: starch solution). The blank was also titrated in the same manner, and the difference in the sodium thiosulfate solution required for the titration was recorded. The amount of sodium thiosulfate required for titration corresponds to the amount of potassium permanganate remaining.Therefore, when a large amount of potassium permanganate reducing substance is contained in the test solution, sodium thiosulfate required for titration is used. Will be less. Therefore, when the titration was completed with an amount of sodium thiosulfate that was aml less than the blank, the difference in potassium permanganate consumption was recorded as + aml. When the difference in consumption of potassium permanganate was 1.0 ml or less, it was regarded as the standard passage. Evaporation residue 20 ml of the test solution was placed in a glass container, evaporated to dryness by heating, and the residue was dried at 105 ° C. The weight of this residue was recorded. When this value was 1.0 mg or less, it was regarded as the standard passage.

(3) Adhesion Behavior of Blood Cell Components Using the PET-PAA-1 described above, a module for evaluation was prepared and the adhesion behavior of blood cells to a nonwoven fabric was evaluated. Although the form of the evaluation module is shown in FIG. 1, between the funnel-shaped molded body 3 having the body fluid introduction port 5 and the funnel-shaped molded body 3 ′ having the body fluid discharge port 6, the nonwoven fabric is provided at the portion 4 Sandwich the
The structure is such that the cap 1 and the cylinder 2 which can be fitted to each other with screws are tightened. 5 ml / min of citrated cow blood
The module was continuously passed through the module at a flow rate of 10 minutes. The blood that passed through the module was taken into a test tube every minute, and the concentration of blood cell components (white blood cells and platelets) was measured by an automatic blood cell counter Sysmex F-800 manufactured by Toa Medical Electronics. From this blood cell concentration, the residual rate of blood cell components after contact with the non-woven fabric was calculated. The results are shown in Fig. 2. The greater the residual rate of blood cells in blood that has come into contact with the nonwoven fabric, the less likely it is that the blood cells will adhere to the nonwoven fabric.

Example 2 The same PET nonwoven fabric as that used in Example 1 was prepared. PEI3 with a molecular weight of 10,000
0 g, EG ₃ -A 5 g, glycerin 5 g, methanol 1
PEI is dissolved in this solution and PET non-woven fabric is immersed in this solution.
And the application of additives was performed. After it was thoroughly dried (60 ° C, 6 hours), E was applied at a dose of 5 Mrad on each side.
B was irradiated to graft PEI onto the surface of the PET nonwoven fabric.

Washing was performed in the same manner as in Example 1 and PE
I-introduced PET nonwoven fabric PET-PEI-2 was obtained. PET
-Quantification of the content of amino groups introduced into PEI-2 and eluate test were carried out by the same method as in Example 1. The amino group content was determined by the method described in Example 1,
0.1N sodium hydroxide in 0.1N hydrochloric acid,
The measurement was performed by changing 1N hydrochloric acid to 0.1N sodium hydroxide, and calculated from the results.
The results are shown in Table 1.

<Example 3> Crosslinked polystyrene porous beads manufactured by Mitsubishi Kasei (Diaion HP20; hereinafter abbreviated as HP20) were placed on a glass filter and thoroughly washed with acetone. PAA having a molecular weight of 4000, 15 g, EG ₃ -A
5 g and 5 g of glycerin were dissolved in 1 liter of methanol, and HP20 was immersed in this solution to apply PAA and additives. HP20 was collected with a glass filter and dried sufficiently (60 ° C., 6 hours). After drying, it was evenly spread on a tray and irradiated with EB at a dose of 10 Mrad to graft PAA onto the surface of the crosslinked polystyrene porous beads.

Washing was carried out in the same manner as in Example 1, and PA
A-introduced polystyrene beads PS-PAA-3 were obtained. P
The quantification of the content of the carboxyl group introduced into S-PAA-3 and the eluate test were carried out by the same method as in Example 1. The results are shown in Table 1.

Example 4 PEI3 having a molecular weight of 10,000
0 g, EG ₃ -A 5 g, glycerin 5 g, methanol 1
It was dissolved in 1 and the same acetone-washed HP20 used in Example 3 was dipped in this solution to apply PEI and additives. This was collected with a glass filter and sufficiently dried (60 ° C., 6 hours), and then irradiated with EB at a dose of 10 Mrad to graft PEI onto the surface of the crosslinked polystyrene porous beads.

Washing was performed in the same manner as in Example 1, and PE
I-introduced polystyrene beads PS-PEI-4 were obtained. P
Quantification of the content of amino groups introduced into S-PEI-4 and eluate test were carried out by the same method as in Example 2. The results are shown in Table 1.

Comparative Example 1 The same PET nonwoven fabric as that used in Example 1 was prepared. PAA15 with a molecular weight of 4000
g was dissolved in 1 l of methanol, and the PET nonwoven fabric was dipped in this solution to apply PAA. After sufficiently drying (60 ° C., 6 hours), EB was irradiated at a dose of 5 Mrad on one side to try to graft PAA onto the surface of the PET nonwoven fabric.

Washing was performed in the same manner as in Example 1 to obtain a modified PET non-woven fabric PET-PAA'-5. PET-P
Quantification of the content of carboxyl groups introduced into AA'-5,
And the eluate test was carried out by the same method as in Example 1. The results are shown in Table 1.

<Comparative Example 2> The same PET nonwoven fabric as that used in Example 1 was prepared. PEI3 with a molecular weight of 10,000
0 g was dissolved in 1 liter of methanol, and the PET nonwoven fabric was dipped in this solution to apply PEI. After sufficiently drying (60 ° C., 6 hours), EB was irradiated at a dose of 5 Mrad on one side to try to graft PEI onto the surface of the PET nonwoven fabric.

Washing was performed in the same manner as in Example 1 to obtain a modified PET non-woven fabric PET-PEI'-6. PET-P
Quantification of the content of amino groups introduced into EI'-6 and eluate test were carried out by the same method as in Example 2.
The results are shown in Table 1.

Comparative Example 3 PAA30 having a molecular weight of 4000
g was dissolved in 1 liter of methanol, and the same acetone-washed HP20 used in Example 3 was immersed in this solution to obtain P.
AA was applied. Collect this with a glass filter,
After being sufficiently dried (60 ° C., 6 hours), EB was irradiated at a dose of 10 Mrad to try to graft PAA onto the surface of the crosslinked polystyrene porous beads.

Washing was performed in the same manner as in Example 1 to obtain modified polystyrene beads PS-PAA'-7. PS-
The quantification of the content of the carboxyl group introduced into PAA′-7 and the eluate test were carried out by the same method as in Example 1. The results are shown in Table 1.

Comparative Example 4 PEI3 having a molecular weight of 10,000
0 g was dissolved in 1 liter of methanol, and the same acetone-washed HP20 used in Example 3 was dipped in this solution to apply PEI. After collecting this with a glass filter and thoroughly drying it (60 ° C., 6 hours), 10 Mra
EB was irradiated at a dose of d to try to graft PEI onto the surface of the crosslinked polystyrene porous beads.

Washing was carried out in the same manner as in Example 1 to obtain modified polystyrene beads PS-PEI'-8. PS-
Quantification of the content of amino groups introduced into PEI′-8 and eluate test were carried out by the same method as in Example 2. The results are shown in Table 1.

<Comparative Example 5> The same PET nonwoven fabric as that used in Example 1 was prepared, a module similar to that of Example 1 was prepared without modification, and the adhesive behavior of blood cell components was evaluated.
The results are shown in Fig. 2.

As is apparent from Table 1, a large amount of functional groups were introduced into the surface-modified polymer molding obtained by the surface modification method of the polymer molding of the present invention, and moreover, it was stably bound. It was found that the eluate was kept low. Also,
It is possible to introduce functional groups into both PET non-woven fabric and polystyrene beads with good efficiency, and although there are some differences in the introduction efficiency, it is suggested that this technology can be applied beyond the shape and material of the molded product. It was

As can be seen from FIG. 2, the surface-modified polymer molding of the present invention (carboxyl group-introduced PET non-woven fabric)
Has an effect of suppressing adhesion of blood cells. From this result, it is suggested that the surface-modified polymer molded product according to the present invention is particularly effective as a blood treatment material for selectively removing a specific component from whole blood.

[0058]

The method for modifying the surface of a polymer molding of the present invention comprises:
Efficiently adding many functional groups to molded products of all shapes,
Moreover, it is possible to introduce stably. For this reason, a method for synthesizing an ion exchange material, a method for synthesizing an enzyme immobilization material by ionic bonding, an antistatic method for various polymer moldings, a technique for improving dyeability of synthetic fibers, synthesis of an enzyme immobilization material, It can be applied to a wide range of fields such as blood adaptation technology. Among them, since a functional group can be introduced by a stable bond, it is particularly effective as a medical material that needs to suppress the eluate.

[Brief description of drawings]

FIG. 1 shows an outline of an evaluation module.

FIG. 2 shows the residual rate of blood cell components in Examples and Comparative Examples.

[Explanation of symbols]

 3. Funnel type molding 4. Non-woven fabric clamping part 5. Body fluid inlet 6. Body fluid outlet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masakazu Tanaka 2-1-1 Katata, Otsu City, Shiga Prefecture Toyobo Co., Ltd.

Claims (4)

[Claims] 1. When a graft chain is introduced onto the surface of a polymer molded body by irradiation with radiation, a substance to be a graft chain can be dissolved, and it does not boil at room temperature to 120 ° C. under atmospheric pressure and has fluidity. A method for modifying the surface of a polymer molded body, which comprises adding an additive capable of retaining 2. A substance to be a graft chain is a carboxyl group, an amino group, an imino group, a sulfonic acid group, a hydroxyl group,
At least one functional group selected from the group consisting of an epoxy ring, an aldehyde group, an acyl group, and a haloacyl group is contained in the molecule.
The method for modifying the surface of a polymer molded body according to claim 1, which is a substance having one or more and a molecular weight of 40 to 40,000. 3. The surface modification method for a polymer molding according to claim 1, wherein the additive is a polyhydric alcohol or a dehydration condensation product of the polyhydric alcohol. 4. The method for modifying the surface of a polymer molding according to claim 1, wherein the additive is a substance having a structure having a plurality of unsaturated bonds in the molecule.