JP2000204183A - Polymer gel carrier and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymer gel carrier wherein a polymer gel is strongly fixed on a base material and comfortably exhibiting a function of the polymer gel carrier and a simple method for producing the polymer gel. SOLUTION: This polymer gel carrier is obtained by performing an oxidation treatment on the surface of a base material made of a polyolefin-based polymeric resin, coating an aqueous solution containing polyvinyl alcohol and polyacrylic acid and freeze-thawing. A hydrogen-bondable group is formed on the surface of a resin by the oxidation treatment and polyvinyl alcohol is gelled by the freeze-thawing to be a polymeric gel 1 and a hydrogen bonding is formed between the polyvinyl alcohol and the surface of the base material 2, then generated polymeric gel 1 is fixed on the base material. The polyacrylic acid contained in the polymeric gel 1 functions as a pH-responsive polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer gel carrier comprising a polymer gel and a substrate supporting the same, and more particularly, to a polymer gel carrier having a stimulus-responsive polymer gel supported on a substrate. And its manufacturing method.

[0002]

2. Description of the Related Art A polymer gel is a substance formed by partially cross-linking polymers to form a three-dimensional knitted structure, which is swollen by a solvent. Has been used as. In recent years, research for functionalizing polymer gels has been conducted for the purpose of application to mechanical applications such as artificial muscles. Above all, research on stimuli-responsive polymer gels whose physical properties change according to environmental conditions such as pH, temperature, humidity, electric field, magnetic field and the like is active. When such a stimuli-responsive polymer gel is used for mechanical applications,
It is necessary to increase the mechanical strength of the polymer gel itself and to fix the polymer gel to a supporting substrate.

In order to improve the strength of a polymer gel, Japanese Patent Application Laid-Open No. 2-110186 proposes a method of mixing an oxide glass with a gel material. In addition, Japanese Unexamined Patent Application Publication No.
JP-A-303444 and JP-A-5-221710 propose a method of dispersing a ceramic powder in a gel material.

As a method of fixing a polymer gel to a supporting substrate, an adhesive is used in Japanese Patent Application Laid-Open No. Sho 57-167834, and in Japanese Patent Application Laid-Open No. 6-1859, a method of fixing the polymer gel to the substrate is used. An adhesive layer is provided between them.

[0005]

The method of mixing oxide glass or ceramic powder with a gel material is useful for improving the strength of the polymer gel itself. However,
Oxide glass and ceramic powder do not interact with the substrate and do not contribute to the fixation of the polymer gel to the substrate. Also,
In the method of fixing a polymer gel to a base material using an adhesive, components of the adhesive are mixed into the polymer gel to become impurities, which may impair stimulus responsiveness. In addition, in addition to the preparation of the polymer gel, a step of applying an adhesive to the substrate and forming an adhesive layer is required, and the production efficiency of the polymer gel carrier is not good.

The present invention has been made in view of the above-mentioned problems, and a polymer gel carrier in which a polymer gel is firmly fixed to a base material and the polymer gel exhibits excellent functions, and its simple structure. It is intended to provide a simple manufacturing method.

[0007]

According to the present invention, there is provided a polymer gel carrier comprising a polymer gel and a base material supporting the polymer gel, wherein the polymer gel is formed by hydrogen bonding. It shall be fixed to the material. In this configuration, the polymer gel is directly fixed to the base material, and no foreign matter such as an adhesive is interposed between the two. For this reason, impurities do not mix into the polymer gel, and there is no possibility that the function of the polymer gel is impaired.

Here, it is preferable that the polymer gel contains a polymer having a hydroxyl group, for example, polyvinyl alcohol. Since the hydroxyl group is a good hydrogen donor and an acceptor in hydrogen bonding, the fixation of the polymer gel to the base material becomes strong. In addition, hydrogen bonds are formed between the polymers, resulting in a polymer gel having high mechanical strength.

Specifically, the polymer gel is a stimulus-responsive gel that expands or contracts in response to an external stimulus.
In this case, the polymer gel carrier converts stimulus into volume change, and can be used for mechanical applications. Since the polymer gel is fixed to the base material, it does not slip on the base material, and changes in volume according to the magnitude of the stimulus. Therefore, the volume change can be controlled by the magnitude of the stimulus. The stimulus is, for example, a change in pH.

The substrate may have a hydrogen-bonding functional group on the surface. That is, the substrate does not need to be hydrogen-bonded inside, and its internal structure does not matter. For example, the substrate can be a polyolefin-based polymer whose surface is oxidized.

In order to achieve the above object, the present invention also provides a method for producing a polymer gel carrier comprising a polymer gel and a substrate supporting the polymer gel. Is formed, thereby fixing the polymer gel to the base material. Since the hydrogen bond is a strong bond, the polymer gel is securely fixed to the substrate. Further, since no foreign matter such as an adhesive is used for fixing, there is no possibility that impurities are mixed into the polymer gel and the function of the polymer gel is impaired.

In particular, a substrate having a hydrogen-bonding functional group on its surface is used as a substrate, and a liquid containing a hydrogen-bonding polymer is brought into contact with the substrate and freeze-thawed, so that the hydrogen-bonding polymers can be separated from each other. A hydrogen bond is formed between the hydrogen bonding polymer and the substrate. In this method, the polymer gel is fixed to the substrate simultaneously with the formation of the polymer gel, and the number of steps is small. As the hydrogen bonding polymer, for example, a polymer containing polyvinyl alcohol is used.

As the base material, a polyolefin polymer whose surface has been oxidized can be used. Usually, polyolefin-based polymers do not have a hydrogen-bonding functional group, but by performing an oxidation treatment, it is possible to introduce a hydrogen-bonding functional group such as a carbonyl group or a hydroxyl group onto the surface. As the oxidation treatment, a heat treatment in an oxidizing gas atmosphere, an oxygen plasma treatment, a corona discharge treatment, or an inorganic mineral acid treatment is employed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows a structure of a boundary portion between a polymer gel 1 and a substrate 2 of a polymer gel carrier of the present invention. The polymer 1a constituting the polymer gel 1 has many hydrogen-bonding functional groups, and the substrate 2 also has many hydrogen-bonding functional groups on its surface, and both serve as donors and acceptors. To form hydrogen bonds (indicated by dotted lines in the figure). By these hydrogen bonds, the polymer gel 1 is firmly fixed to the substrate 2.

In FIG. 1, the polymer 1a has a hydroxyl group,
The base material 2 has a hydroxyl group and a carbonyl group, but the hydrogen bonding functional group provided to the polymer 1a and the base material 2 is not limited to these. For example, a carboxyl group, an amino group, an amide group, a sulfo group and the like are also good hydrogen bonding functional groups, and these can also be used.

Although not shown, inside the polymer gel 1,
Chemical bonds such as a hydrophobic bond, an ionic bond, and a hydrogen bond are formed between the polymers 1a by Van der Waals force, and the polymer 1a is three-dimensionally crosslinked by these bonds to form a gel. These bonds generated between the polymers 1a are the main factors that determine the mechanical strength of the polymer gel 1, and among them, the hydrogen bond has a large contribution due to its large energy.

As the polymer 1a constituting the polymer gel 1, any polymer, natural or synthetic, can be used as long as it has an appropriate number of hydrogen-bonding functional groups. In the case of a synthetic polymer, if each monomer unit has a hydrogen bonding functional group, the number of hydrogen bonding increases,
It is preferable because not only the fixing strength to the base material is increased, but also the crosslinking between the polymers is increased, so that the mechanical strength of the polymer gel itself is improved. As such a polymer, for example,
There is polyvinyl alcohol. Polyvinyl alcohol having a high degree of saponification is preferable because of its high mechanical strength.

The substrate 2 only needs to have a hydrogen-bonding functional group on its surface, and the inside may have any structure. The material of the base material 2 is selected in consideration of flexibility, strength, difficulty of processing, and the like, and suitable for use of the polymer gel carrier. The metal oxide or paper itself has a hydrogen bonding ability and can be used as the base material 2 as it is.

A synthetic resin such as plastic can also be used as the material of the base material 2. Polyolefin polymers such as polyethylene and polypropylene are particularly suitable because they are low in cost and easy to set in shape and flexibility. However, since these synthetic resins do not have a hydrogen bonding functional group, the surface is subjected to an oxidation treatment to introduce the hydrogen bonding functional group.

As the oxidation treatment, heat treatment in an atmosphere of an oxidizing gas such as air or oxygen, oxygen plasma treatment, corona discharge treatment, or inorganic mineral acid treatment can be employed.
These treatments are preferable because they hardly affect the inside of the synthetic resin and hardly cause deterioration or reduction in strength. Another oxidation treatment may be performed.

Whether or not a hydrogen bonding functional group has been introduced to the surface of the substrate by the oxidation treatment can be confirmed by spectroscopic analysis such as X-ray photoelectron spectroscopy and infrared spectroscopy. If a spectrum specific to an oxygen atom is detected, it becomes clear that a hydrogen bonding functional group has been introduced.

There are various methods for gelling the polymer 1a, and any of the methods may be employed. In the present embodiment, the solution of the polymer 1a is kept in contact with the substrate 2 by freeze-thawing. Is performed, the formation of the polymer gel 1 and the fixing of the polymer gel 1 to the base material 2 are performed at one time. The freeze-thaw is performed once or plural times in a temperature range of, for example, -20 to 20 ° C. A plurality of polymers 1a are hydrogen-bonded to form a three-dimensional knitted structure, resulting in a polymer gel 1 having high mechanical strength. At the same time, the polymer 1a and the base 2 are hydrogen-bonded to form a polymer gel. 1 is fixed to the substrate 2.

When the polymer gel 1 is formed to be relatively thin, a solution of the polymer 1a is applied to the substrate 2 using a method such as dip coating, spin coating, bar coating, or air knife coating, and the solution is freeze-thawed. I do. When the polymer gel 1 is formed to be relatively thick, the solution of the polymer 1a is set to a desired depth, and freeze-thawing is performed in a state where the substrate 2 is in close contact with the liquid surface. Application of the solution and freeze-thawing may be repeated.

When the polymer gel 1 has a function such as stimulus responsiveness, another polymer (hereinafter referred to as a functional polymer) which expresses the function by gelation is contained in a solution of the polymer 1a. Perform freeze-thaw. The polymer gel 1 produced in this manner has a functional polymer uniformly distributed. Depending on the type of the functional polymer, the hydrogen ion concentration (p
H), various polymer gels 1 which expand or contract in response to changes in temperature, humidity, electric field, magnetic field and the like are obtained.

For example, when polyacrylic acid is used as the functional polymer, a polymer gel 1 which responds to a change in pH can be obtained. Polyacrylic acid has a large number of carboxyl groups directly linked to the main chain, and this acidic group serves as a stimulus responsive function part. That is, the dissociation state of the carboxyl groups changes according to the pH, and the affinity between the carboxyl groups greatly changes depending on the state, resulting in a change in the three-dimensional stitch structure of the polymer gel 1.

Specifically, when the pH is small and carboxyl groups are not so dissociated, hydrogen bonds are formed between carboxyl groups of neighboring polyacrylic acids, and the spacing between the main chains of polyacrylic acid becomes narrow. In a state where the pH is large and most of the carboxyl groups are dissociated, the carboxylate ions of neighboring polyacrylic acids repel each other, and the interval between the main chains of polyacrylic acid is widened. This change causes a change in the size of the three-dimensional network structure of the polymer gel 1, and the polymer gel 1 contracts when the pH is low (the hydrogen ion concentration is high) and increases when the pH is high (the hydrogen ion concentration (Low) when it expands.

Therefore, the volume of the polymer gel 1 can be controlled by adjusting the pH of the environment. For example, a polymer gel 1 made from polyvinyl alcohol having a degree of saponification of 99% and a degree of polymerization of 1700 and polyacrylic acid having a molecular weight of 2200 contracts about 10% when the pH is changed from pH 7 to pH 3.

Functional polymers that respond to changes in pH include, besides polyacrylic acid, polymethacrylic acid, polyvinyl sulfonic acid, polyacrylamide, and alkali metal salts of each acid. These can be used as well.

When poly-N-isopropylacrylamide is used as the functional polymer, a polymer gel 1 which responds to a change in temperature can be obtained. This polymer has a large number of amide groups as the stimulus response function part, and changes in the three-dimensional stitch structure of the polymer gel 1 due to changes in the hydration structure of the amide groups.

When the ambient temperature is low, there is an internal hydration layer in which the amide group is strongly hydrated around the main chain of poly-N-isopropylacrylamide, and the external hydration layer is relatively weak with the water of the internal hydration layer outside. There is an external hydration layer bonded by force, and the polymer gel 1 is in a swollen state. When the ambient temperature rises,
When the molecular movement of water becomes active, the outer hydrated layer separates from the inner hydrated layer and becomes free water. As a result, the polymer gel 1 loses water and contracts.

For example, polyvinyl alcohol and a degree of polymerization of 1
The polymer gel 1 made from 000 poly-N-isopropylacrylamide undergoes a phase transition at about 37 ° C. and shrinks as the temperature is raised from room temperature. As a functional polymer that responds to changes in temperature, polyvinyl methyl ether can also be used.

A polymer having an ionic functional group or a polarizable functional group, such as the above-mentioned polyacrylic acid, can be used as a functional polymer responding to a change in an electric field. For example, in a polymer gel 1 made of a polymer having a carboxyl group such as polyacrylic acid, dissociated hydrogen ions are attracted to the minus side in an electric field, and the repulsion between carboxylate ions is increased, thereby swelling.
When the electric field is removed, the hydrogen ions recombine with the carboxylate ions, the repulsion decreases, and the polymer gel 1 contracts.

In the polymer gel 1 having the stimulus responsiveness as described above, the volume change can be controlled by the magnitude of the stimulus. At this time, since the polymer gel 1 is fixed to the substrate 2, the polymer gel 1 does not slip on the substrate 2, and the volume change of the polymer gel 1 can be used as a mechanical driving force. It is possible to reliably control the volume change.

The functional polymer mixed with the polymer 1a also interacts with the polymer 1a and contributes to the improvement of the strength of the polymer gel 1. What is used as the polymer 1a or the functional polymer is preferably determined in consideration of not only the type of function provided to the polymer gel 1 but also the obtained mechanical strength. The mixing ratio between the polymer 1a and the functional polymer is also preferably determined in consideration of the size of the function to be exhibited and the mechanical strength.

Experiments for examining the effectiveness of the present invention for fixing the polymer gel 1 and the base material 2 by hydrogen bonding will be described with reference to several examples.

<Preparation of Samples> Five types of samples of the present invention and five types of samples of comparative examples were prepared as follows.

Example 1 9% by weight of polyvinyl alcohol (polymerization degree: 1400, saponification degree: 99 mol%) was added to a polypropylene resin plate oxidized at 60 ° C. for 1 hour with a 10% by weight aqueous solution of chromic acid.
A mixture of 1 wt% of polyacrylic acid (degree of polymerization 4000) and 90 wt% of ion-exchanged water was applied, and then freeze-thaw (-20 to 20 ° C) was repeated 5 times.

Example 2 A polypropylene resin plate oxidized with 0.5 mol / l nitric acid at 60 ° C. for 1 hour was mixed with 9 wt% of polyvinyl alcohol (degree of polymerization 1400, saponification degree 99 mol%), poly-N-isopropylacrylamide (Degree of polymerization 1700)
A mixture of 1 wt% and 90 wt% of ion-exchanged water was applied, and then freeze-thaw (-20 to 20 ° C.) was repeated 5 times.

Example 3 A polypropylene resin plate oxidized with a 5 wt% aqueous phenol solution at 30 ° C. for 1 hour was mixed with 9 wt% of polyvinyl alcohol (polymerization degree: 1700, saponification degree: 99 mol%).
A mixed solution of 1 wt% of polyacrylic acid (polymerization degree 1000) and 90 wt% of ion-exchanged water was applied, and then freeze-thaw (-20 to 20 ° C.) was repeated 5 times.

Example 4 A polyethylene resin plate treated in a 3 mol% oxygen / argon plasma for 10 minutes was charged with 9 wt% of polyvinyl alcohol (degree of polymerization 1400, saponification degree 99 mol%), 1 wt% of polymethacrylic acid (degree of polymerization 1000), Then, a mixed solution of 90 wt% of ion-exchanged water was applied, and then freeze-thawing (-20 to 20 ° C.) was repeated 10 times.

Example Sample 5 A polyethylene resin plate irradiated with 50,000 kV negative corona discharge in air for 10 seconds was charged with 9 wt% of polyvinyl alcohol (degree of polymerization 2600, degree of saponification 99 mol%).
%, Polyvinyl sulfonic acid (degree of polymerization 1800) 1 wt
%, And a mixed solution of 90 wt% of ion-exchanged water,
Thereafter, freeze-thawing (-20 to 20 ° C) was repeated 10 times.

Comparative Sample 1 9 wt. Of polyvinyl alcohol (degree of polymerization 1400, degree of saponification 99 mol%) was placed on an untreated polypropylene resin plate.
%, 1 wt% of polyacrylic acid (degree of polymerization 4000), and 90 wt% of ion-exchanged water were applied, and then freeze-thawing (-20 to 20 ° C) was repeated 5 times.

Comparative Sample 2 9 wt. Of polyvinyl alcohol (degree of polymerization 1400, degree of saponification 99 mol%) was placed on an untreated polypropylene resin plate.
%, Poly-N-isopropylacrylamide (degree of polymerization 1
700) A mixture of 1 wt% and 90 wt% of ion-exchanged water is applied, and then freeze-thaw (−20 to 20 ° C.) is performed for 5 minutes.
Repeated times.

Comparative Sample 3 9 wt. Of polyvinyl alcohol (degree of polymerization 1700, degree of saponification 99 mol%) was placed on an untreated polypropylene resin plate.
%, 1 wt% of polyacrylic acid (polymerization degree 1000), and 90 wt% of ion-exchanged water were applied, and then freeze-thawing (-20 to 20 ° C) was repeated 5 times.

Comparative Example Sample 4 9 wt% of polyvinyl alcohol (degree of polymerization 1400, degree of saponification 99 mol%) was placed on an untreated polyethylene resin plate.
A mixed solution of 1 wt% of polymethacrylic acid (polymerization degree: 1000) and 90 wt% of ion-exchanged water was applied, and then freeze-thaw (−20 to 20 ° C.) was repeated 10 times.

Comparative Example Sample 5 9 wt% of polyvinyl alcohol (degree of polymerization 2600, degree of saponification 99 mol%) was placed on an untreated polyethylene resin plate.
A mixture of 1 wt% of polyvinyl sulfonic acid (degree of polymerization 1800) and 90 wt% of ion-exchanged water was applied, and then freeze-thaw (-20 to 20 ° C.) was repeated 10 times.

<Peeling Test> For each of the above samples,
A test for peeling off the polymer gel and the substrate was performed according to the IS peeling test method. Specifically, a rectangular sample piece having the following dimensions is cut out from each sample, and at one end in the longitudinal direction of the sample piece, a force perpendicular to the surface of the base material and opposite to each other is applied to the polymer gel and the base material. Added.

Example Sample 1 When a sample piece was set to 50 × 100 mm and a force was applied for 5 seconds, the polymer gel was torn and the polymer gel remained attached to the substrate surface.

Example Sample 2 When a sample piece was made 50 × 100 mm and a force was applied for 5 seconds, the polymer gel was torn, and the polymer gel remained attached to the surface of the substrate.

Example Sample 3 When a sample piece was 80 × 200 mm and a force was applied for 10 seconds, the polymer gel was torn, and the polymer gel remained attached to the substrate surface.

Example Sample 4 A sample piece was 80 × 200 mm, and when a force was applied for 10 seconds, the polymer gel was torn and the polymer gel remained attached to the substrate surface.

Example Sample 5 When a sample piece was set to 50 × 100 mm and a force was applied for 10 seconds, the polymer gel was torn, and the polymer gel remained adhered to the substrate surface.

Comparative Example Sample 1 When a sample piece was made 50 × 100 mm and a force was applied, the polymer gel was separated from the substrate surface without tearing.

Comparative Example Sample 2 When a sample piece was made 50 × 100 mm and a force was applied, the polymer gel was peeled off from the substrate surface without tearing.

Comparative Example Sample 3 A sample piece was 80 × 200 mm, and when a force was applied, the polymer gel was peeled off from the substrate surface without tearing.

Comparative Example Sample 4 A sample piece was 80 × 200 mm, and when a force was applied, the polymer gel was separated from the substrate surface without tearing.

Comparative Example Sample 5 A sample piece was made 50 × 100 mm, and when a force was applied, the polymer gel was peeled off from the substrate surface without tearing.

<Confirmation Test for Presence of Hydrogen-Bonding Functional Group on Substrate Surface>
Line photoelectron spectroscopy or Fourier transform infrared spectroscopy (FT-
IR), the presence of an oxygen atom serving as a hydrogen bonding functional group was examined.

X-ray photoelectron spectroscopy of the polypropylene substrate used in Example 1 showed a peak of 543.1 eV indicating the binding energy of the oxygen atom in the 1s orbital.

X-ray photoelectron spectroscopy of the polypropylene substrate used in Example 2 showed a peak at 543.1 eV indicating the binding energy of the oxygen atom in the 1s orbital.

X-ray photoelectron spectroscopy of the polypropylene substrate used for Comparative Example Sample 1 showed no peak indicating the binding energy of the oxygen atom in the 1s orbital.

X-ray photoelectron spectroscopy of the polypropylene substrate used for Comparative Example Sample 2 did not show any peak indicating the binding energy of the oxygen atom in the 1s orbital.

In the FT-IR polypropylene base material used in Example 3, an absorption spectrum at 1,730 cm ⁻¹ showing a carbonyl bond was observed.

The polyethylene base material FT-IR used in Example sample 4 showed an absorption spectrum at 1,730 cm ^-1 indicating a carbonyl bond.

The polyethylene base material FT-IR used in Example sample 5 showed an absorption spectrum at 1,730 cm ^-1 indicating a carbonyl bond.

In the polypropylene base material FT-IR used for Comparative Example Sample 3, no absorption spectrum showing the bonding of oxygen atoms was observed.

In the polyethylene base material FT-IR used for Comparative Example Sample 4, no absorption spectrum showing the bonding of oxygen atoms was observed.

In the polyethylene base material FT-IR used for Comparative Example Sample 5, no absorption spectrum showing the bonding of oxygen atoms was observed.

From these two experiments, it was found that the oxygen atoms constituting the hydrogen-bonding functional group were introduced into the polyolefin polymer by the oxidation treatment, and that the polymer gel was firmly attached to the oxidized polyolefin polymer base material. It became clear that the polymer gel was hardly fixed to the polyolefin-based polymer base material not subjected to the oxidation treatment. Therefore, it can be said that the hydrogen bond between the two greatly contributes to the fixation of the polymer gel to the substrate.

<Stimulus Responsiveness Test> The pH responsiveness and the temperature responsiveness of some of the above samples were examined. The pH responsiveness test is performed by immersing a specimen of a predetermined size in an aqueous acetic acid solution of pH 3.5 gently for a day and a night. This was carried out by immersing the ion-exchanged water kept gently all day and night.

Example Sample 1 In the pH responsiveness test, the thickness of the polymer gel was 20
%, But no peeling of the polymer gel from the substrate occurred.

Comparative Example Sample 1 In the pH responsiveness test, the thickness of the polymer gel was 20
% And the polymer gel detached from the substrate.

Example Sample 2 According to the temperature response test, the thickness of the polymer gel was 10%.
%, But no peeling of the polymer gel from the substrate occurred.

Comparative Example Sample 2 According to the temperature response test, the thickness of the polymer gel was 10
% And the polymer gel detached from the substrate.

From the stimulus responsiveness test, it was confirmed that the volume of the polymer gel changed in response to pH and temperature, and if the polymer gel and the base material were not hydrogen-bonded, both could be easily formed. Separation, whereas if hydrogen-bonded, p
It was confirmed that the polymer gel remained fixed to the base material even when the H or temperature changed.

As described above, the polymer gel carrier of the present invention can reliably fix the polymer gel to the base material, and can provide the polymer gel with stimulus responsiveness and a variable pore size filter.
It is suitable for use in mechanical applications such as artificial muscles. According to the method of the present invention, a polymer gel carrier in which a polymer gel is firmly fixed to a substrate can be manufactured in a short process only by preparing a substrate having a hydrogen bonding functional group on the surface. Can be.

[0086] By freezing and thawing the polymer gel in contact with the base material, the number of steps is increased instead of forming the polymer gel and fixing the polymer gel to the base material at one time. The polymer gel prepared in advance may be fixed to the substrate by hydrogen bonding in a separate step. In that case, a liquid having the same or similar composition as that of the polymer gel may be applied to the substrate, and the polymer gel may be placed on the substrate and freeze-thawed.

[0078]

According to the polymer gel carrier of the present invention, since the polymer gel is directly fixed to the substrate by hydrogen bonding, impurities are mixed into the polymer gel as in the case of using an adhesive. There is no possibility that the function of the polymer gel is impaired. Further, since the hydrogen bond is a strong bond, the polymer gel does not peel off from the substrate.

When the polymer gel contains a polymer having a hydroxyl group such as polyvinyl alcohol, the fixation of the polymer gel to the base material becomes strong, and the mechanical strength of the polymer gel itself also increases. .

When the polymer gel is a stimuli-responsive gel that expands or contracts in response to an external stimulus, the polymer gel carrier can be used for mechanical applications. Since the polymer gel is fixed to the base material and the stimulus responsiveness does not decrease due to impurities, it is easy to control the volume change of the polymer gel due to the stimulus.

When a polyolefin polymer whose surface is oxidized is used as the substrate, the cost of the substrate is reduced, and the polymer gel carrier becomes inexpensive. In addition, processing such as cutting of the polymer gel carrier after production is easy.

According to the method for producing a polymer gel carrier of the present invention, the polymer gel can be securely fixed to the substrate by utilizing the fact that the hydrogen bond is a strong bond.
Further, since no foreign matter such as an adhesive is used for fixing, there is no possibility that impurities are mixed into the polymer gel and the function of the polymer gel is impaired.

In particular, a substrate having a hydrogen-bonding functional group on its surface is used as a substrate, and a liquid containing the hydrogen-bonding polymer is brought into contact with the substrate and freeze-thawed, so that the hydrogen-bonding polymers are separated from each other. When a hydrogen bond is formed between the hydrogen-bonding polymer and the base material, the polymer gel is fixed to the substrate simultaneously with the formation of the polymer gel. Therefore, the number of steps is reduced as compared with the conventional method in which the polymer gel is fixed to the base material after the formation of the polymer gel, and the production efficiency is improved.

When a polymer containing polyvinyl alcohol is used as the hydrogen-bonding polymer, the number of hydroxyl groups is large and the number of hydrogen bonds is also increased, thereby increasing the strength of the polymer gel itself and the strength of fixing the polymer gel to the base material. .

When a polyolefin polymer whose surface is oxidized is used as a substrate, the production cost can be reduced, and the substrate is relatively soft, so that the polymer gel carrier after the production is easily processed. become.

When a heat treatment in an oxidizing gas atmosphere, an oxygen plasma treatment, a corona discharge treatment, or an inorganic mineral acid treatment is adopted as the oxidation treatment of the base material, only the surface can be easily oxidized, and the base material can be easily oxidized. Deterioration and reduction in strength can be avoided. Moreover, the processing itself is easy.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a structure of a boundary portion between a polymer gel and a substrate of a polymer gel carrier of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polymer gel 1a Polymer 2 Base material

Claims (14)

[Claims] 1. A polymer gel carrier comprising a polymer gel and a base material supporting the polymer gel, wherein the polymer gel is fixed to the base material by hydrogen bonding. Gel carrier. 2. The polymer gel carrier according to claim 1, wherein the polymer gel contains polyvinyl alcohol. 3. The polymer gel carrier according to claim 1, wherein the polymer gel is a stimulus-responsive gel that expands or contracts in response to an external stimulus. 4. The polymer gel carrier according to claim 3, wherein the stimulus is a change in pH. 5. The polymer gel carrier according to claim 1, wherein the substrate has a hydrogen-bonding functional group on the surface. 6. The polymer gel carrier according to claim 5, wherein the base material is a polyolefin polymer having a surface oxidized. 7. A method for producing a polymer gel carrier comprising a polymer gel and a base material supporting the polymer gel, wherein a hydrogen bond is formed between the polymer gel and the base material. A method for producing a polymer gel carrier, comprising fixing a molecular gel to the substrate. 8. A substrate having a hydrogen-bonding functional group on its surface as a substrate, and a liquid containing a hydrogen-bonding polymer is brought into contact with the substrate and freeze-thawed, whereby the hydrogen-bonding property is increased. The method for producing a polymer gel carrier according to claim 7, wherein a hydrogen bond is formed between molecules and between the hydrogen bonding polymer and the substrate. 9. The method according to claim 8, wherein a polymer containing polyvinyl alcohol is used as the hydrogen bonding polymer. 10. The method for producing a polymer gel carrier according to claim 7, wherein a polyolefin polymer having a surface oxidized is used as the substrate. 11. The method according to claim 10, wherein the oxidation treatment is a heat treatment in an oxidizing gas atmosphere. 12. The method according to claim 10, wherein the oxidation treatment is an oxygen plasma treatment. 13. The method for producing a polymer gel carrier according to claim 10, wherein the oxidation treatment is a corona discharge treatment. 14. The method according to claim 10, wherein the oxidation treatment is an inorganic mineral acid treatment.