JPH0753751A - Method for making hydrophobic substance hydrophilic - Google Patents

Abstract

PURPOSE:To prolong life, reduce man-power, simplify operations, improve water permeability, reduce weight, and inhibit the proliferation of bacteria by bringing a specific silicon compd. into contact with a hydrophobic substance to cause the condensation at the interface of contact. CONSTITUTION:A hydrophobic substance (e.g. a porous polyolefin hollow-fiber film) is made hydrophilic by dissolving, in an org. solvent, a low-molecular compd. of the formula (wherein R is a hydrocarbon group; R' is an alkoxy or acyloxy; and (n) is 0, 1, or 2) which gives a low-viscosity soln. applicable uniformly and thinly, has a silicon atom in the molecule, forms cross-linking groups (hydroxyl groups) on contact with atmospheric moisture (water), and spontaneously undergoes three-dimensional condensation to give a silicon-contg. polymer with a polysiloxane structure, applying the resulting soln. to the surface of the hydrophobic substance, and drying the soln. at room temp., under heating, or in a vacuum to cause the condensation of the compd. provided that the condensation is carried out in the presence of glycerol by applying it in an amt. of at least 0.5% of the soln. to the surface before it is coated with the soln. or by adding glycerol to the soln. after it is applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for imparting hydrophilicity to a hydrophobic substance, and is widely used for imparting hydrophilicity to a hydrophobic film and hydrophilizing a hydrophobic molded article.

[0002]

2. Description of the Related Art Heretofore, a method of applying a hydrophilic substance to the surface to make the surface hydrophilic has been known as the most commonly used means for imparting hydrophilicity to a hydrophobic surface. There is. Although this method is simple in method, it has a drawback that the hydrophilic substance used for coating is easily detached from its surface in the case of low molecular weight. A typical example is hydrophilization with alcohol. For example, hydrophobic fluororesins and polyolefin resins do not accept water, but they can be wetted with water by first treating them with alcohol and then substituting the alcohol with water. However, the method using a low molecular weight hydrophilic substance has a short-term effect, and has an essential drawback that once the surface is dried, it returns to the original hydrophobic property again.

The next conceivable method is a method of coating a hydrophobic substance with a hydrophilic polymer substance. If a hydrophilic polymer substance is applied to the surface of a hydrophobic substance, its release from the surface can be considerably suppressed, but since it has compatibility with water, it will not be released with time and its effect will be reduced. It is well known. In order to solve this, it has been attempted to insolubilize the hydrophilic substance applied on the surface of the hydrophobic substance in water. The most effective means for this is a crosslinking method, particularly a three-dimensional crosslinking method. It is well known that when a polymer is three-dimensionally crosslinked, it becomes insoluble in all solvents including water. The cross-linking method is a chemical method using a cross-linking agent. There are physical methods such as radiation, electron beam, or ultraviolet irradiation. The operation of each of these is extremely complicated. Furthermore, it is extremely difficult to evenly or thinly apply a hydrophobic surface with a polymer substance. This is due to the high viscosity of the solution as a characteristic of the polymer substance. It should be extremely difficult to apply a highly viscous material thinly and uniformly to the hydrophobic surface. In order to efficiently make the hydrophobic surface hydrophilic, it is extremely difficult with the current technology to meet the essential conditions of using a polymer and performing a cross-linking means. With the current technology, an unnecessarily thick hydrophilic polymer is applied. In addition, there are many problems that the coating state is not uniform and the thickness of the coating layer is not constant, and in addition, the spots where the coating is leaked statistically occur. In addition, a complicated operation of a cross-linking means is indispensable, resulting in a high cost momentum.

[0004] Therefore, the present situation is that no method has yet been proposed to solve the efficient, inexpensive and uniform hydrophilization of a hydrophobic surface, even though its appearance has long been desired. When the technology for making the hydrophobic substance hydrophilic is completed, many application fields will be opened. One of the applied fields is application to hollow fibers. BACKGROUND ART In recent years, hollow fiber manufacturing techniques and the resulting hollow fiber membranes that have been made porous to be used in industry have been actively used, and their practical application is steadily progressing.

Polyolefin, that is, a porous membrane of polypropylene or polyethylene or a so-called porous hollow fiber membrane in which the membrane shape is tubular has been established as a considerably excellent technique. Polyolefin hollow fibers having a pore size of 0.5 μm or less are drawing attention as a new material for artificial lungs. When polyolefins, such as polypropylene, are used to make the desired porous hollow fiber membranes, water cannot pass through the membrane walls of the hollow fibers due to its inherent hydrophobicity and surface tension of water. Utilizing this, for example, when the gas is exchanged by flowing blood to one side, that is, inside or outside of the porous hollow fiber of polypropylene, and flowing oxygen gas to the other side, the blood may pass through the membrane wall. On the other hand, on the other hand, since the exchange of oxygen monocarbonate gas is efficiently performed, it exhibits an excellent function as a gas exchange membrane of a heart-lung machine. This is a skillful use of the hydrophobicity of the polypropylene porous membrane, but on the other hand, the fact that water does not pass through the membrane wall due to this hydrophobicity is a major obstacle on the contrary when considering other industrial fields. . For example, if you want to purify water using polypropylene hollow fiber membranes, try to filter industrial wastewater of hydrogen, or try to filter blood for medical industry applications, you can Because of this, filtration cannot be performed,
It is self-evident that the hydrophobicity of all of these hollow fiber membranes will be a major obstacle and stand out.

Various methods have been tried to overcome these problems. For example, there is a method of coating the surface of the hollow fiber with a hydrophilic polymer or a surfactant. In this method, it is technically difficult to coat a hydrophilic polymer on a porous film, and a very uneven coating is often produced, and even a slight difference in the coating conditions greatly changes the resulting coating state. Many pores, which are the essence of a porous film, may be filled up, which is a problem in quality control of products. An even bigger problem is that these hydrophilic polymers and surfactants dissolve at least partially in water and are gradually eluted.
This is not only a problem of the life of hydrophilization, but also a problem of being eluted gradually even when it is used for medical applications and food applications. Therefore, although coating with a hydrophilic polymer or a surfactant is useful as a means for making a hydrophobic film hydrophilic, it is not perfect and there are many demands for improvement.

[0007]

In order to avoid such a problem, a means for reducing or evacuating one of the inside and the outside of the hollow fiber of the polyolefin or vice versa is used. Then, there is a method in which water is forcibly introduced into the hole and the water is filled as it is. This method is one solution because water can pass through the pores of the hollow fiber membrane as long as the water is not drained as it is, but it is a large solution, requires a large amount of manpower, and causes water to penetrate into the hydrophobic pores. Is not perfect, and once the air bubbles have penetrated during use, the water permeability of that part no longer works. Another method is to once wet the hydrophobic hollow fiber membrane with an organic solvent, replace the organic solvent with water, and finally fill the pores with water. In this method, it is necessary that the organic solvent to be used be replaced with water, so that it must be easily soluble in water, and methanol, ethanol, acetone, tetrahydrofuran or the like is preferably used.

Compared with the above-mentioned introduction of water into the pores by pressurization or depressurization, the degree of completeness in the filling degree of water into the pores is high,
The operation is simple and the most practical method. However, the common drawback of these is that, in addition to the need for an organic solvent and high cost, the hollow fiber must always be kept immersed in water after being hydrophilized, which is heavy and heavy. It has drawbacks such that the bacteria easily propagate and the sterilization such as high-pressure steam sterilization is required. Ideally, the hydrophobic surface must be able to be made hydrophilic with high accuracy, that it can be kept in a dry state, and that the coated material does not elute completely in water. , It can be said that there is currently no such thing.

[0009]

[Means for Solving the Problems] The present inventors have arrived at the present invention by studying a method for making a hydrophobic surface hydrophilic by a completely different concept from the conventional method. The inventors of the present invention have considered that it is necessary to satisfy the following basic conditions as a result of various studies when hydrophilizing the hydrophobic surface. That is, (1) the hydrophilic substance when applied to the surface of the hydrophobic substance,
In order to apply uniformly, thinly and evenly, the viscosity of the coating solution is low, and therefore the hydrophilic coating substance must have a low molecular weight, and (2) the uniformly and thinly coated substance is a high molecular substance after coating. What to convert to.
(3) Moreover, the polymer substance should be crosslinked to be insoluble and the hydrophilicity should be maintained. As a result of various searches by the present inventor for a hydrophilic substance satisfying these conditions, a certain silicon-containing compound, more specifically,
A method using a low-molecular-weight silicon-containing cross-linking agent that produces three or more cross-linkable functional groups (hydroxyl groups) by the activation treatment has been conceived.

The present invention is characterized in that a silicon-containing compound which is activated by water to induce condensation polymerization to form a crosslinkable polysiloxane is brought into contact with a hydrophobic substance and a condensation reaction is carried out on the contact surface. Crosslinkable polysiloxanes are commonly used for hydrophilizing hydrophobic substances.

[0011]

[Chemical 2] (Wherein R is a hydrocarbon residue, R ′ is an alkoxy group or an acyloxy group, and n = 0, 1, 2), and the condensation reaction is further performed. The present invention relates to a method for hydrophilizing a hydrophobic substance, wherein the method is performed in the presence of glycerin.

In this case, only the one having two methyl groups on the silicon atom, such as dimethyldiacetoxysilane,
The bifunctional and produced polysiloxane becomes a hydrophobic polydimethylsiloxane, and the object of the present invention cannot be achieved because it is a linear polymer without cross-linking. For example, those having trifunctionality or more, such as methyltriacetoxysilane and tetramethoxysilane, that is, those having 3 to 4 functional groups represented by Si-OH in water are extremely reactive and repeatedly undergo dehydration condensation with each other. It becomes a three-dimensional polysiloxane, has a small number of hydrophobic groups (CH ₃ —), and Si—OH does not completely react, and —OH groups remain everywhere, so that sufficient hydrophilicity can be maintained. If tetramethoxysilane reacts completely ideally, it becomes (SiO ₂ ) n, which is also hydrophilic. Actually, it does not react completely and hydroxyl groups remain everywhere, and it is possible to maintain a high degree of hydrophilicity.
Further, by using only the completely tetrafunctional one, even if the CH ₃ -group is present, if the above-mentioned methyltriacetoxysilane is slightly mixed, the amount of the segment with (SiO ₂ ) n is the presence of the trifunctional group. The amount of free hydroxyl groups increases and the hydrophilicity can be increased. Further, trifunctional compounds having a CH ₃ group such as methyltriacetoxysilane and methyltriethoxysilane can sufficiently impart hydrophilicity, and it is considered that a considerable amount of free hydroxyl groups are present.

[0013] Advantages of the present invention When the features are listed, the present invention is as follows.
Since it is treated with an organic solvent of a low-molecular-weight silicon compound that is activated by water to form a crosslinkable polysiloxane, the treatment solution has an extremely low viscosity and a uniform treatment (that is, a hydrophobic surface is different from the treatment of the polymer solution). It is extremely easy to wet, has a high degree of completion, does not fill pores unlike a high-viscosity polymer solution because it can be thinly coated, and has a high boiling point as the solvent evaporates. The compound is concentrated on the hydrophobic surface to form an adsorption surface, and the condensation polymerization is performed on the hydrophobic surface with water in the air, so that the surface is thinly covered with the hydrophilic film and the condensate is a three-dimensional polymer. It does not dissolve in water at all, and it solves the problem of elution, and when it crosslinks, it exhibits the same adhesiveness as the function of silicone adhesive, so the coating is stable. Problems of people the one in which was resolved almost all at once.

The term "silicon-containing cross-linking agent" as used herein means that it has one or more silicon atoms in its molecule and is capable of producing a cross-linking ability by a suitable activation method, for example, contact with moisture (moisture) in the atmosphere. A compound having a functional group is used, and more specifically, a compound known as a room temperature crosslinking agent for silicone rubber or silicone resin, that is, a silane coupling agent is used. As these silicon-containing crosslinking agents, those having a functional group activated by water are preferably used.
Typical examples of these are

[0015]

[Chemical 3]

[0016]

[Chemical 4] (R: hydrocarbon residue such as CH ₃ , C ₂ H ₅ , C ₃ H ₇ , C ₄ H ₉ ),

[0017]

[Chemical 5]

[0018]

[Chemical 6] (X: halogen atom such as Cl or Br),

[0019]

[Chemical 7] (R: same as above)

There are, for example, Such a silicon-containing cross-linking agent has a low molecular weight, has a low viscosity in a solution state, and can be applied uniformly and thinly, and an active hydroxyl group is generated by a reaction with moisture in the air, which naturally causes a three-dimensional condensation. The cross-linked silicon-containing polymer thus formed has a polysiloxane structure. Examples of the silicon-containing cross-linking agent having one silicon atom in the molecule that activates by water to exhibit a cross-linking ability and form a polysiloxane cross-linking body include

[0021]

[Chemical 8] (Wherein R represents a hydrocarbon residue such as an alkyl group or an aryl group, R ′ represents an alkoxy group, an acyloxy group, a halogen or an amine residue, and n represents 0 or 1).

Specifically, tetraethoxysilane and methyltriacetoxysilane will be described below as examples.

[0023]

[Chemical 9]

[0024]

[Chemical 10] Since tetraethoxysilane (TES) has a low molecular weight, its acetone solution, for example, has an extremely low viscosity and can be applied uniformly and thinly to the surface of a hydrophobic substance in combination with the hydrophilicity / hydrophobicity of acetone. If the low boiling point acetone evaporates, a very uniform TES becomes a thin film and can cover the hydrophobic surface.

The thin film of TES is easily hydrolyzed by moisture in the air, and Si-OC ₂ H ₅ is changed to Si-OH. This immediately causes a condensation reaction between molecules, and O-Si
An -O bond is generated, resulting in a polysiloxane (crosslinked) structure.

[0026]

[Chemical 11] That is, Si-OH + HO-Si = Si-O-Si +
By the basic reaction of H ₂ O, a tetrafunctional group is condensed to form a cross-linked product, and free hydroxyl groups (—OH) having no condensation reaction partner also remain unreacted depending on the formation position. Such a crosslinked product has moderate hydrophilicity due to the presence of free hydroxyl groups.

[0027]

[Chemical 12]

Methyl tetraacetoxy silane (MTA
In the case of S), the CH ₃ —Si bond is stable, but Si—O
The AC bond is extremely sensitive to water and easily changes into a hydroxyl group.

[Chemical 13]

In this case, since it is trifunctional, the resulting condensate is three-dimensionally crosslinked and naturally becomes an insoluble material. In this case as well, a hydroxyl group that is distant from the corresponding OH that undergoes the condensation reaction is inevitably generated, and it imparts appropriate hydrophilicity. In this case, since MTAS has a low molecular weight at the time of application, it can be applied extremely thinly and evenly to the hydrophobic surface, and when it comes into contact with moisture in the air, active hydroxyl groups are naturally generated and crosslinked naturally. , And the presence of free hydroxyl groups in the meantime can form a hydrophilic surface. The present inventors have arrived at the present invention in which, while pursuing the conditions for hydrophilization based on such a basic reaction, a method for further hydrophilizing was found. That is, it has been found that the presence of glycerin when applying the above-mentioned silicon-containing crosslinking agent realizes a surprisingly high degree of hydrophilicity. Such a phenomenon has not been reported at all until now, and is the discovery of the present inventor. During the above reaction, glycerin intervenes there to react with glycerin as shown in formula (B).
It is considered that this is a result of forming a member ring (a) or a 6-membered ring (b) and generating a hydrophilic ether bond (-O-) bond or free -OH.

[0030]

[Chemical 14] A high degree of hydrophilicity is achieved because of the incorporation of hydrophilic glycerin molecules in such crosslinking reactions. In other words, by interposing glycerin in the hydrophilization reaction, a surprisingly high degree of hydrophilization was achieved by a simple operation.

Specific examples of the silicon-containing cross-linking agent having one silicon atom in the molecule, which is used in the present invention and which is activated by water to exert a cross-linking ability to form a cross-linked polysiloxane, include, for example, etraacetoxysilane. , Methyltriacetoxysilane, ethyltriacetoxysilane, propyltriacetoxysilane, butyltriacetoxysilane, phenyltriacetoxysilane, methyltriethoxysilane, ethyltriethoxysilane, tetraethoxysilane, phenyltriethoxysilane, propyltriethoxy Silane, propyltriethoxysilane, methyltrimethoxysilane, tetramethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane or tetrachlorosilane, methyltrichlorosilane, Chill trichlorosilane, butyl trichlorosilane, vinyl triacetoxy silane, bis -
(N-methylbenzylamide) ethoxymethylsilane,
Typical examples include tris- (dimethylamino) methylsilane, vinyltrichlorosilane, tris- (cyclohexylamino) methylsilane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, tetrapropoxysilane, and divinyldiethoxysilane. Can be done.

Typical examples of silicon-containing crosslinking agents containing two silicon atoms in the molecule include, for example, hexaacetoxydisiloxane, 1,3-dimethyltetraacetoxydisiloxane and 1,3-divinyltetraethoxydisiloxane. General formula, such as

[0033]

[Chemical 15] (Where n, m = 0, 1, 2, 3, n + m = 0, 1, 2,
3, R is a hydrocarbon residue having no crosslinking ability, R ′,
R "represents a group exhibiting a cross-linking ability by a suitable activation means).

An example of a silicon-containing cross-linking agent containing three silicon atoms in its molecule is 1,3,5-trimethoxy-1,1,3.
5,5 pentamethyltrisiloxane, 1,1,3,3,
Examples include 5,5-hexaacetoxy-1,5-dimethyltrisiloxane.

As these silicon-containing cross-linking agents, known room-temperature cross-linking type silane coupling agents are widely used. For example, Petrarch System Incorporated (Petr).
arch System Inc. ) Issued by Silicon Compounds,
All silicon-containing crosslinking agents described in Register & Review, 1979 and Silicon (Silicones), 1981 can be used.

Crosslinkability (that is, trifunctionality) as described above
In addition to the silicon-containing compound of
Needless to say, a low-molecular-weight silicon-containing compound that sequentially forms O—Si bonds to form polysiloxane may be used together. As such a bifunctional silicon-containing compound, a silicon atom has two hydrocarbon groups, and two molecules in the molecule have a functional group which is activated by water to generate a crosslinkability.

[0037]

[Chemical 16] (In the formula, R _{1 to} R ₄ are the same or different hydrocarbon groups, n is a positive integer such as 0.1, 2, 3, Y and Y ′ are the same or different cross-linkable functional groups activated by water. Represents each of the above).

These compounds contain two non-crosslinkable hydrocarbon groups in the silicon atom and two crosslinkable functional groups in the molecule, and dimethyldiacetoxysilane is an example.
Diethyldiacetoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, methylethyldimethoxysilane, diethyldimethoxysilane, dimethyldichlorosilane, methylphenyldiacetoxysilane, diphenyldiacetoxysilane, dibenzyldiacetoxysilane, divinyldiethoxy There is silane. Also 1,1,
3,3-tetramethyl-1,3-diacetoxydisiloxane, 1,1,3,3-tetramethyl-1,3-dimethoxydisiloxane, 1,1,3,3-tetraethyl-
1,3-diethoxydisiloxane, 1,1,3,3,
5,5-hexamethyl-1,5-diacetoxytrisiloxane, 1,1,3,3,5,5-hexaethyl-1,
5-diethoxytrisiloxane, 1,1,3,3,5
5-hexamethyl-1,5-dimethoxytrisiloxane, 1,1,1,5,5,5-hexamethyl-3,3-
Diacetoxytrisiloxane, 1,1,1,3,5,5
-Hexamethyl-3,5-diacetoxytrisiloxane and the like.

When such a functional compound is added, a linear molecular chain due to —Si—O—Si— bond is lengthened in the produced polymer, in other words, the crosslinking concentration can be reduced. The resulting polymer becomes elastic, which is advantageous for some purposes. As shown in the formula (A), the formation reaction of the polymer containing silicon is activated by water in the air and spontaneously condenses by a sequential reaction to form a polysiloxane molecule. Forming a 5-membered ring or 6-membered ring having a hydrophilic ether bond having a hydroxyl group with glycerin. Therefore, the resulting crosslinked condensate is extremely hydrophilic, and since it is three-dimensionally crosslinked, it is hydrophilic. However, since it does not dissolve in water, the hydrophilized surface is characterized by being permanently stable.

In addition, in the method of the present invention, crosslinking is spontaneously promoted by moisture in the air without performing a binding operation for imparting hydrophilicity, and the reaction component is a low molecular weight compound during coating. The characteristics are that it is possible to coat a hydrophobic surface uniformly and in a thin film very easily, and the hydrophilicity is retained for a long time.

The most important point of the present invention is to interpose glycerin in the hydrophilization. The presence of glycerin incorporates glycerin into the condensation reaction as shown in formula (B) to form hydrophilic 5-membered ring (a) and 6-membered ring (b) containing a hydroxyl group and an ether bond. 5
Due to the formation of the six-membered ring and the six-membered ring, the molecular chains of the crosslinked condensate are prevented from approaching each other by this cyclic product. This is because the hydroxyl group (unreacted) bonded to silicon exists in a free state and the condensation reaction partner is released. The reaction between the hydroxyl groups is inhibited, and as a result, the free hydroxyl groups remain, which further improves the hydrophilicity. Therefore, the presence of glycerin constitutes the extremely significant second feature of the present invention, and constitutes the basic principle of highly hydrophilicity.

Another feature of the present invention is that when coating the solution in the presence of glycerin, the solution may contain glycerin in advance, or the hydrophobic surface to be hydrophilized first may be applied. Glycerin may be applied and then the solution may be applied thereon. Alternatively, the solution may be first applied and then glycerin may be added by some method, for example, spraying.

The amount of glycerin used in the present invention is preferably 0.5% or more based on the solution, preferably 1%.
% Or more, more preferably 3% or more. Glycerin itself may be used as a solvent. In this case, glycerin is 100% in the solvent itself used. However, since glycerin itself is highly viscous, it is recommended to dilute it with another solvent. After applying the solution, it may be dried at room temperature, or may be heated, dried, or vacuum dried. Also, heated gas may be sent. The condensation reaction of the present invention is most preferably carried out in a natural atmosphere with moisture in the air, but steam or air or other gas containing steam may be sent to accelerate the reaction. Further, at the stage where the condensation reaction has progressed to some extent, it is possible to take a means of immersing it in water to further promote the reaction. Practically, the one subjected to the coating treatment of the present invention is simply held in a clean room, the activation of the present invention by the moisture in the atmosphere, and the successive condensation reaction is naturally extremely rich in labor saving, Can provide an economical way. The application of the present invention has a very wide range of application of the basic method, and it is also possible to convert a hydrophobic film into a hydrophilic film.

[0044]

The present invention pays attention to the reactivity of Si-OH and utilizes a silicon-containing compound that produces Si-OH by the water content in the atmosphere. It has succeeded in providing a new technology for forming siloxane and making a hydrophobic surface uniformly hydrophilic.

[0045]

EXAMPLES The present invention will be described in more detail below by way of examples. As an example of the hydrophobic substance, polypropylene will be described as a representative, but the present invention is by no means limited to the examples, and the hydrophobic property is not limited thereto. It can be applied by making the substance hydrophilic, and does not limit the scope of the present invention.

Example 1 Polypropylene (manufactured by Ube Industries) was melt-spun by a conventional method with a circular slit nozzle having a diameter of 30 mm to 116 m / mi.
It was wound at a winding speed of n. 150 for 5 minutes with this hollow fiber
Heat treatment was carried out at 0 ° C., and then the film was introduced into a liquid nitrogen refrigerant at −196 ° C. and stretched here by 15%. The hollow fibers were subsequently heat treated at 150 ° C. for 45 seconds. The number of hollow fibers obtained is 1
It was introduced into an air bath adjusted to 35 ° C. and stretched to a rate of 300% at a rate of 17.5% / min. In this process, the hollow fiber tube wall was fibrillated into a uniform, sloppy porous tube. This porous hollow fiber has a diameter of 320 μm and a tube wall thickness of 5
It was 5 μm and the average pore diameter measured by the bubble point method was 0.25 μm. Since the obtained fiber is hydrophobic, water cannot pass through it.When a hollow fiber type artificial lung module was manufactured using this fiber, blood showed useful performance without leaking from the hollow fiber and gas exchange capacity. Was also excellent.

Acetone containing 22% of a mixture of methyltriacetoxysilane-dimethyldiasexisilane (weight ratio 1: 3) in the hollow portion of the polypropylene hollow fiber that does not pass through the tube wall because both water and blood are hydrophobic. Introduce the solution, depressurize the outside of the hollow fiber, pressurize the inside,
The acetone solution was allowed to pass through the hollow fiber tube wall so as to wet the entire tube wall. After that, air was sent to purge this solution from the pores of the porous portion. In this state, the treated hollow fiber module was kept for 12 days in an atmosphere of 65% relative humidity. During this time, the hollow fibers were uniformly coated with polysiloxane while liberating acetic acid. When water was pressed through the hollow portion of the hollow fiber module to pressurize the water, the water smoothly passed through the hollow fiber tube wall and was filtered.

Example 2 Polypropylene (UBE-PP-J109 manufactured by Ube Industries, Ltd.)
G) was melt-spun into hollow fibers by a conventional method using a circular slit nozzle having a diameter of 7 mm and a width of 1 mm. The temperature of the spinning cylinder is 210 ° C., the spinning speed is 200 m / min, and the draft rate is 7.
It was 26. This hollow fiber was heat treated in an air bath at 145 ° C for 6 minutes and then introduced into liquid nitrogen at -195 ° C for 2 minutes.
It was stretched by 0%. This was subsequently heat-treated in an air bath at 145 ° C. for 2 minutes to fix the structure. 1 more hollow fiber
Stretching 380% in air kept at 40 ° C by 17.3%
At a speed of 1 / min for fibrillation treatment at 145 ° C
Was heat-treated for 2 minutes to fix the structure. The obtained hollow fiber formed a uniformly fibrillated porous tube wall, the pore shape measured by the bubble point method was 0.56 μm, the inner diameter of the polypropylene hollow fiber was 320 μm, and the tube wall pressure was 57 μm. . Using this hollow fiber, a hollow fiber type module having a membrane area of 0.5 m ² was prepared. Since this hollow fiber is made of polypropylene, it is hydrophobic, and even if water is added to the hollow portion of this hollow fiber and pressure is applied, no water can pass through the tube wall, and it does not function as a filtration membrane at all.

This hollow fiber module was treated with two kinds of solutions (A) and (B) prepared as follows. (A): 6 parts of methyltridiacexysilane (hereinafter "part")
Is a part by weight), 4 parts of dimethyldiacetoxysilane, and 40 parts of acetone. (B): 6 parts of methyltriacetoxysilane, 4 parts of dimethyldiacetoxysilane, 10 parts of glycerin, 3 parts of acetone
A solution consisting of 0 parts. That is, 0.5 m using the (A) solution and the (B) solution
^Two hollow fiber modules were prepared using the hollow fiber of Example 2 of the present invention having a membrane area of 2. One is a solution treated with (A) and the other is treated with a solution (B). In the method, (A) or (B) solution is pressed into the hollow portion of the hollow fiber, and a pressure of 100 mmHg is applied to the solution to form a pipe wall. The entire tube was wetted with the treatment liquid by flowing out to the outside, and then the air was sent to purge the excess treatment liquid.

The hollow fiber thus treated was kept at room temperature, left as it was for 1 week and then exposed to water vapor to complete the condensation reaction and dry it. Using hybrid dogs, an attempt was made to separate plasma from blood using the hollow fiber module treated as described above. The adult dog used in this experiment weighed 10.5 kg. Plasma separation was performed without any problem, and it was shown that the treatment completely hydrophilized the blood. The filtration coefficient of plasma albumin after 120 minutes of plasma separation operation time is
The (A) liquid treatment module had 0.93 and the (B) liquid treatment module had 0.96, and the total cholesterol was (A).
It was 0.91 for the liquid treatment module and 0.93 for the (B) liquid treatment module. As shown in this Example, it was proved that the treated hollow fiber can be an extremely excellent plasma separation membrane as a plasma separation membrane which has been conventionally hydrophobic and completely unusable.

Example 3 3 parts of tetraethoxysilane, 7 parts of diethoxydimethylsilane and 5 parts of glycerin were dissolved in 30 parts of ethyl acetate,
To this, 1 part of glacial acetic acid was added to prepare a uniform solution. 0.3 mm thick polyethylene film (3 cm x 3 c
Two m) were prepared, and one of them was immersed in the above ethyl acetate solution, then taken out and air dried as it was. The film was placed in an atmosphere of 60% relative humidity for 12 days and then vacuum dried. When one drop of water was dropped on this treated film, the water drop immediately spread on the film and the wet state was good. Similarly, when a drop of water was dropped on the same polyethylene film that had not been subjected to this treatment, the drop of water did not spread at all and the surface was hydrophobic and did not get wet at all.

Claims (3)

[Claims] 1. Hydrophilicity of a hydrophobic substance, characterized in that a silicon-containing compound which is activated by water to form a crosslinkable polysiloxane by a condensation reaction is brought into contact with a hydrophobic substance and a condensation reaction is carried out on the contact surface. Method. 2. A compound containing a silicon atom in the molecule which is activated by water to form a crosslinked polysiloxane has the general formula: The hydrophobicity according to claim 1, which is at least one selected from the group represented by the formula (R in the formula is a hydrocarbon residue, R'is an alkoxy group or an acyloxy group, and n = 0, 1, 2). Method for making a substance hydrophilic. 3. A silicon-containing compound that is activated by water to form a crosslinkable polysiloxy compound by a condensation reaction is brought into contact with a hydrophobic substance, and when the condensation reaction is carried out on the contact surface, the reaction is carried out in the presence of glycerin. The method for hydrophilizing a hydrophobic substance according to claim 1, wherein