JP5682447B2 - Slurry organic-inorganic composite gel and method for producing organic-inorganic composite gel coating film - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a slurry-like organic-inorganic composite gel and a method for producing an organic-inorganic composite gel coating film, which are excellent in surface smoothness and useful for the production of a thin-layer gel coating film. Available.

  A polymer gel is a soft material swollen with water or an organic solvent in a three-dimensional network structure of an organic polymer, and is used in the medical, food, civil engineering, sports related, or electronic / electrical fields. There is a demand to form a gel thinly on a base material, and medical ships and poultices are used by thinly applying a gel or adhesive containing a drug to the base material. In these, the thickness of the gel is generally one hundred microns or more, and the surface state such as smoothness is not required to have a very high accuracy. On the other hand, attempts have been made to use gel in the electrolyte layer in battery materials such as lithium ion batteries and capacitors. In this case, it is necessary to form a thin-layer gel on the base material, and since blurring of the gel leads to blurring of the characteristics, those having a smooth surface are required, and further, the strength of the gel In particular, a material having a high strength against compression is required.

  In recent years, nanocomposite gels (hereinafter referred to as “NC gels”) containing an aqueous medium in a three-dimensional network of organic polymers and clay minerals have attracted attention because of their high water swellability and excellent mechanical properties. (See Non-Patent Documents 1 and 2). Patent Document 1 discloses a method of thinning a film-like NC gel sheet by a method such as heating press. However, there are problems that the film thickness obtained by this method is limited and the process is complicated. Moreover, when pasting and using on a base material, it was necessary to make it adhere | attach. Patent Document 2 discloses a particulate NC gel dispersion. However, this method is a method in which emulsion polymerization is carried out in a hydrocarbon solvent, which increases the cost and necessitates removal of the used hydrocarbon. Further, since the particle size is relatively large, there is a problem that the surface of the obtained coating film is rough. On the other hand, Patent Document 3 shows that a gel excellent in mechanical strength can be obtained by re-swelling an NC gel that has been dried and pulverized into a powder, and can be formed into an arbitrary shape. ing. However, although the gel coating film obtained by this method is relatively excellent in mechanical strength, the surface smoothness is poor, and only a coating film with surface irregularities can be obtained. There was a problem of requiring an additive. Patent Document 4 discloses an aqueous dispersion of clay and polymer having the same composition as NC gel and its coating film. However, the obtained coating film has extremely low water swelling ability and can be contacted with water. There is no gel. As described above, it is difficult to obtain a thin gel coating film having high surface smoothness and excellent mechanical properties and capable of containing a specific medium by any conventionally known method. .

JP 2010-95586 PR Japanese Unexamined Patent Publication No. 2011-012107 JP2011-1482 PR Patent No. 4430124

K. Haraguchi, T. Takehisa, Advanced Material 2002, Vol. 14, pp. 1120-1124. Haraguchi Kazutoshi, Chemistry and Industry, 2005, Vol. 58, No. 4, 457-460

  This invention is providing the manufacturing method of the thin layer gel coating film which has the smooth surface and was excellent in the mechanical physical property which can contain a specific medium and a solute.

  After synthesizing an organic-inorganic composite gel by polymerizing a water-soluble radical polymerizable monomer in the presence of a water-swellable clay mineral with a predetermined amount of water, the organic-inorganic composite gel is swollen so that the amount of aqueous medium falls within a specific range. After swelling, or after swelling, an aqueous medium is further added, and then the organic-inorganic composite gel is pulverized to prepare a slurry-like organic-inorganic composite gel. An organic-inorganic composite gel coating film that is excellent in mechanical properties, smooth, thin, and contains the target medium and solute by impregnating the medium or medium containing a solute after forming a coating film using the same. The present invention was found out.

That is, in the present invention, the water-soluble radically polymerizable monomer (A) having one (meth) acrylamide group or (meth) acryloyloxy group in the molecule and the water-swellable clay mineral (B) are added to the aqueous medium (C). An aqueous solution in which the mass ratio (K) of the aqueous medium (C) represented by the following formula (1) is 3 to 15 is dissolved or dispersed therein, and the water-soluble radical polymerizable monomer is prepared at this time. The ratio (W _B / W _A ) of the mass of the water-swellable clay mineral (B) to ( _A ) is 0.03 to 2.0,
Step 1 of obtaining an organic-inorganic composite gel by polymerizing the water-soluble radical polymerizable monomer (A) in the aqueous solution,
Step 2 of swelling the organic-inorganic composite gel in water so that (K) is 40 to 200,
Step 3 of pulverizing the swollen organic-inorganic composite gel,
The manufacturing method of the slurry-like organic inorganic composite gel obtained by this is provided.
Formula (1) (K) = W _C / (W _A + W _B )
(W _C represents the mass of the aqueous medium (C), W _A represents the mass of the water-soluble radical polymerizable monomer (A), and W _B represents the mass of the water-swellable clay mineral (B).)

The present invention also provides a water-soluble radically polymerizable monomer (A) having one (meth) acrylamide group or (meth) acryloyloxy group in the molecule and a water-swellable clay mineral (B) in an aqueous medium (C). An aqueous solution in which the mass ratio (K) of the aqueous medium (C) represented by the following formula (1) is 3 to 15 is dissolved or dispersed therein, and the water-soluble radical polymerizable monomer is prepared at this time. The ratio (W _B / W _A ) of the mass of the water-swellable clay mineral (B) to ( _A ) is 0.03 to 2.0,
Formula (1) (K) = W _C / (W _A + W _B )
(W _C represents the mass of the aqueous medium (C), W _A represents the mass of the water-soluble radical polymerizable monomer (A), and W _B represents the mass of the water-swellable clay mineral (B).)
Step 1 of obtaining an organic-inorganic composite gel by polymerizing the water-soluble radical polymerizable monomer (A) in the aqueous solution,
Step 2 of swelling the organic-inorganic composite gel in water so that (K) is 25 to 100,
Furthermore, Step 3 is performed by adding water (D) to the swollen organic-inorganic composite gel so that {(W _C + D) / (W _A + W _B )} is 40 to 200, and crushing.
The manufacturing method of the slurry-like organic inorganic composite gel obtained by this is provided.

  The slurry-like organic-inorganic composite gel obtained by the production method of the present invention can be applied to various substrates, is a thin layer, excellent in mechanical properties and smoothness, and contains a specific medium or solute. Since a composite gel coating can be formed, it is effectively used as a gel coating and an electrolyte gel required in the electronic / electric field.

The surface observation photograph of the dry coating film obtained in Example 1. FIG. The surface observation photograph of the gel coating film obtained in Example 1. The surface observation photograph of the dried coating film obtained in Comparative Example 1.

  The water-soluble radically polymerizable monomer (A) in the present invention is a radically polymerizable monomer having one (meth) acrylamide group or (meth) acryloyloxy group in the molecule, and has a property of being dissolved in water. is there. The aqueous medium referred to in the present invention includes, in addition to water alone, a mixed solvent with an organic solvent miscible with water and containing water as a main component.

  Examples of the radical polymerizable monomer having a (meth) acrylamide group include acrylamide, an acrylamide derivative monomer, methacrylamide, and a methacrylamide derivative monomer, and those having an acrylamide group such as acrylamide or a derivative monomer thereof are particularly preferably used. Specifically, the acrylamide derivative monomer includes N-alkyl acrylamide and N, N-dialkyl acrylamide, and the methacrylamide derivative monomer includes N-alkyl methacrylamide and N, N-dialkyl methacrylamide. Here, an alkyl group having 1 to 4 carbon atoms is particularly preferably selected. On the other hand, as a radical polymerizable monomer having a (meth) acryloyloxy group, methoxyethyl acrylate, ethoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, ( Examples include poly) ethylene glycol acrylate, (poly) ethylene glycol methacrylate, and dipropylene glycol acrylate.

  As the water-soluble radical polymerizable monomer (A), it is also effective to use a plurality of different radical polymerizable monomers selected from these in addition to the single radical polymerizable monomer shown above. In particular, it is preferable to use a radical polymerizable monomer having a (meth) acrylamide group and a radical polymerizable monomer having a (meth) acryloyloxy group in combination. An example is a copolymer of poly (N, N-dimethylacrylamide) and poly (methoxyethyl acrylate). Here, a polymer of a water-soluble radically polymerizable monomer having an acrylamide group has an effect of acting as a crosslinking point in an organic-inorganic composite gel because it has a strong interaction with a water-swellable clay mineral. can get. On the other hand, a polymer of a water-soluble radically polymerizable monomer having a (meth) acryloyloxy group has an effect of stably containing a medium. Furthermore, when a water-soluble radical polymerizable monomer having a (meth) acryloyloxy group whose glass transition temperature is not more than room temperature is used in combination with a radical polymerizable monomer having a (meth) acrylamide group, an organic-inorganic composite There is an effect of promoting the integration of the microgel as a coating film.

  As the water-swellable clay mineral (B) in the present invention, water-swellable clay minerals, preferably those having the property of swelling between layers by water, are used. More preferably, it is a layered clay mineral that can be at least partially exfoliated and dispersed in layers in water, and particularly preferably a lamellar clay mineral that can be exfoliated and dispersed uniformly in water with a thickness of 1 to 10 layers. For example, water-swellable smectite or water-swellable mica is used. More specifically, water-swellable hectorite containing sodium as an interlayer ion, water-swellable montmorillonite, water-swellable saponite, water-swellable synthetic mica, etc. Is mentioned.

The mass ratio (W _B / W _A ) of the water-swellable clay mineral (B) to the water-soluble radical polymerizable monomer (A) in the present invention is preferably 0.03 to 2.0, more preferably 0.05 to 1.5, particularly preferably 0.1 to 0.7. If it is less than 0.03, the mechanical properties of the gel may be impaired, and if it exceeds 2.0, the gel film-forming ability is reduced.

  In the present invention, a small amount of an organic crosslinking agent can be used in combination for the purpose of further improving the mechanical properties (particularly creep resistance and strength) of the gel coating finally obtained. As the organic crosslinking agent, a water-soluble radically polymerizable monomer (F) having two or more double bonds in the molecule is used, and in particular, two (meth) acrylamide groups and two (meth) acryloyl groups. A radical polymerizable monomer having an oxy group is preferably used. Specific examples include acrylamide derivatives such as N, N′-methylenebisacrylamide, and (meth) acrylates such as diethylene glycol (meth) acrylate and dipolyethylene glycol (meth) acrylate. These organic crosslinking agents are usually added and used together with the radical polymerizable organic monomer (A).

  The amount of the organic crosslinking agent used is 0.001 to 1 mol% of the aqueous solution radical polymerizable monomer (F) having two or more double bonds in the molecule with respect to 1 mol of the aqueous solution radical polymerizable monomer (A). Is preferable, more preferably 0.01 to 0.2 mol%, particularly preferably 0.01 to 0.1 mol%. If it exceeds 1 mol%, the gel may become brittle, and if it is less than 0.001 mol%, the intended effect is not great.

  In the present invention, the slurry-like organic-inorganic composite gel is obtained by polymerizing the water-soluble radical polymerizable monomer (A) in a specific amount of the aqueous medium (C) in the presence of the layer-peeled water-swellable clay mineral (B). After preparing the composite gel, the gel is swollen in water, and further, water (D) is added according to the swelling rate at that time, followed by pulverization. In addition, in this specification, it uses at the time of manufacture of an organic inorganic composite gel, and the water by which almost the whole quantity was taken in in a gel and the water taken in in an organic inorganic composite gel are described as "aqueous medium (C)." .

Good in order to obtain a slurry-like organic-inorganic composite gel, when the W _C mass of the aqueous medium (C), the mass of the W _A water-soluble radical-polymerizable monomer, a W _B and the mass of the water dispersible clay mineral It is necessary to obtain an organic-inorganic composite gel using (K) = W _C / (W _A + W _B ) in an aqueous medium mass ratio in the range of 3 to 15 (step 1). In the range where K is less than 3 and exceeds 15, the organic-inorganic composite gel used in the next step is often unsuitable, such as non-uniformity or reduced mechanical properties.

  In the present invention, the organic-inorganic composite gel obtained in the above step 1 is swollen in water so that the K of the aqueous medium (C) finally contained in the gel is 40 to 200, and then obtained. A slurry-like organic-inorganic composite gel is produced by the step 3 of pulverizing the swollen organic-inorganic composite gel. Here, when the K of the gel obtained in Step 2 is less than 40, it is difficult to obtain a good slurry-like organic-inorganic composite gel in Step 3, and when K exceeds 200, the slurry-like organic-inorganic composite gel is applied. In many cases, the workability is lowered or the mechanical properties of the gel coating film are lowered.

  Moreover, in manufacture of the slurry-like organic inorganic composite gel of this invention, K of the aqueous medium (C) finally contained in the gel becomes 20-100 for the organic inorganic composite gel obtained at the process 1. Step 2 of swelling in water, water (D) is then added to the obtained swollen organic-inorganic composite gel, and the sum K of the aqueous medium (C) and water (D) contained in the gel is 40 to 200 It can also be manufactured by the step 3 of adding and crushing. Here, if K in Step 2 is less than 20, slurrying in Step 3 does not proceed uniformly, and if K exceeds 100, a slurry-like organic-inorganic composite gel excellent in coatability due to slurrying in Step 3 is obtained. It may not be obtained. Further, if K in Step 3 is outside the range of 40 to 200, the same problem as described in the previous section occurs.

  As the aqueous medium (C) in the present invention, ion-exchanged water, ultrapure water, distilled water or the like can be used. In addition, as the aqueous medium (C) in the present invention, in addition to water alone, a good homogeneous solution with a radical polymerizable monomer (A), a water-swellable clay mineral (B), a polymerization initiator and the like is prepared. For the purpose, it is also possible to use an organic solvent which is uniformly mixed with water and mixed with water. Examples of the organic solvent uniformly mixed with water include alcohols such as methanol, ethanol and 2-propanol, ketone solvents such as acetone, ethers such as tetrahydrofuran, amide solvents such as dimethylformamide and dimethylacetamide, and the like. The amount of the solvent is 50% by mass or less, preferably 30% by mass or less, more preferably 10% by mass or less in the aqueous solution used for the polymerization. If the amount of the organic solvent mixed is large, the dispersibility of the water-swellable clay mineral (B) may be impaired. In addition, the water or aqueous solution used in the polymerization is preferably one obtained by removing dissolved oxygen by vacuum degassing and / or bubbling such as nitrogen or argon.

  The polymerization reaction of the water-soluble radically polymerizable monomer (A) in the present invention includes peroxidation to a homogeneous aqueous solution comprising the water-soluble radically polymerizable monomer (A), the water-swellable clay mineral (B), and the aqueous medium (C). A method of polymerizing by adding a thermal polymerization initiator such as a product, a photopolymerization initiator or further a polymerization accelerator thereof and maintaining the temperature at room temperature or heating or ultraviolet irradiation is used.

The thermal polymerization initiator and catalyst used in the present invention can be appropriately selected from hydrophilic thermal polymerization initiators and catalysts. Specifically, as the thermal polymerization initiator, peroxides such as potassium peroxodisulfide and ammonium peroxodisulfide, VA-044, V-50, V-501, VA-057 (manufactured by Wako Pure Chemical Industries, Ltd.) An azo compound such as) is preferably used. In addition, a radical initiator having a polyethylene oxide chain is also used. As the catalyst, tertiary amine compounds such as N, N, N ′, N′-tetramethylethylenediamine and β-dimethylaminopropionitrile are preferably used.
As the ultraviolet polymerization initiator used in the present invention, both hydrophilic and water-insoluble initiators can be used, and water-insoluble initiators are particularly preferable. Benzoin derivatives such as acetophenone, dimethoxybenzyl, benzoinphenylcarbinol, hydroxymethylphenylpropanone, hydroxycyclohexylphenylketone, and the like can be used. These water-insoluble polymerization initiators can be dispersed in a very small amount in a clay water dispersion, or dissolved in advance in a water-soluble radical polymerizable monomer (A) or an organic solvent uniformly mixed with a small amount of water. After that, it can be dispersed in a clay water dispersion. For the ultraviolet irradiation, a known ultraviolet irradiation apparatus, for example, a commercially available ultraviolet irradiation apparatus using an ultraviolet light source such as high pressure mercury, low pressure mercury, metal halide, or xenon can be used. The irradiation time varies depending on the intensity of ultraviolet rays used, the amount of the initiator, the amount of the reaction solution, and the like, and is usually selected in the range of several seconds to 1 hour.

The amount of the thermal polymerization initiator and the photopolymerization initiator used is preferably 0.01 to 2% by mass, particularly 0.02 to 1% by mass, based on the total mass (W _A + W _B ) of the monomer and the clay mineral. Even if it exceeds 2% by mass, the effect is not changed, and unnecessary components increase. If it is less than 0.01% by mass, the polymerization yield and the like may be insufficient. In addition, it is possible to use together a well-known thickener, a leveling agent, a defoaming agent, and a filler in the organic-inorganic composite microgel dispersion within a range that does not impair the object of the present invention.

  The polymerization temperature used in the present invention is set in accordance with the types of radical polymerizable monomer, polymerization catalyst, initiator, and the like. Usually, the thermal polymerization is performed in the range of 0 to 100 ° C, preferably 10 to 90 ° C, more preferably 50 to 80 ° C, and the ultraviolet polymerization is performed in the range of 0 to 50 ° C, preferably in the range of 0 to 30 ° C. Done in The polymerization time varies depending on conditions such as the catalyst, initiator, polymerization temperature, and amount of aqueous solution, and is not particularly limited, but it is generally performed for several tens of seconds to several tens of hours. The polymerization atmosphere is preferably used in an inert gas atmosphere such as nitrogen or argon for both thermal polymerization and ultraviolet polymerization.

  As a manufacturing method of the organic-inorganic composite gel coating film in the present invention, the slurry-like organic-inorganic composite gel is used as it is, or after adjusting the viscosity by adjusting the moisture content, etc., a die coater, a roll coater, etc. Apply using a coater or brush, and then dry until one end is water-free or low water content, then impregnate with water or a specific medium (E) to form an organic-inorganic composite gel coating film. How to get is essential. Examples of the method of impregnating the dry coating film with the medium (E) include a method of immersing in the medium, a method of contacting the medium, and a method of applying the medium.

  The medium (E) in the present invention is selected from those uniformly contained according to the purpose and used, for example, water, an organic solvent, or an ionic liquid. Organic solvents include alcohols such as methanol and ethanol, polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin, liquid polyhydric alcohol polymers such as polyethylene glycol and polypropylene glycol, and ketones such as acetone and methyl ethyl ketone. Solvents, chain ethers such as diethyl ether and methyl cellosolve, cyclic ethers such as tetrahydrofuran and dioxane, ester solvents such as ethyl acetate, cyclic esters such as ε-caprolactone, γ-butyrolactone and δ-valerolactone, carbonic acid Chain and cyclic carbonates such as diethyl, dimethyl carbonate, ethyl methyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, vinyl ethylene carbonate Solvent, acetonitrile, propionitrile, nitrile solvents such as butyronitrile, aromatic hydrocarbons such as toluene and xylene, halogenated solvents such as Kurororumu or methylene chloride. Among these, as the medium (E) used in the present invention, it is preferable to use a carbonate solvent, a lactone solvent, or a nitrile solvent. These organic solvents may be used alone or in combination with a plurality of solvents including water. As the ionic liquid, a room temperature molten salt that is liquid at room temperature is used, and an imidazolium salt derivative, a biridinium salt derivative, an alkylammonium salt derivative, or a phosphonium salt derivative is used.

  In the present invention, it is preferable to include a solute (F) such as an inorganic salt, an electrolyte, or an organic molecule in the medium (E). The solute (F) that can be added to the medium (E) is selected from compounds that can be uniformly dispersed or dissolved in the medium (E), for example, electrolytes and salts according to the purpose. Specifically, examples of the electrolyte include hydroxides such as potassium hydroxide and sodium hydroxide, carbonates such as sodium carbonate and lithium carbonate, chlorides such as lithium chloride and calcium chloride, sodium chlorate, and perchlorine. (Per) chlorates such as lithium acid, calcium perchlorate and magnesium perchlorate, fluorinated borates such as lithium tetrafluoroborate, sodium tetrafluoroborate and potassium tetrafluoroborate, phosphorus hexafluoride Fluorophosphates such as lithium phosphate, sodium hexafluorophosphate, potassium hexafluorophosphate, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (trifluoroethanesulfonyl) imide, lithium trifluoromethanesulfonate, etc. Examples thereof include fluorinated imide salts and fluorinated sulfonates. Furthermore, carboxylic acids such as adipic acid, maleic acid, benzoic acid, phthalic acid and salicylic acid, amines such as triethylamine and tetramethylammonium hydroxide, ammonium salts, collagen, vitamins and the like can be mentioned.

  The organic-inorganic composite gel coating film obtained by impregnating the medium (E) or the medium (E) containing the solute (F) is a uniform gel having surface smoothness and is often integrated. When the production method according to the present invention is used, a thin surface smooth gel coating film having a thickness of 100 microns or less can be obtained, and the gel is isolated from the substrate and used as a single organic-inorganic composite gel film. You can also The organic-inorganic composite gel film can be bent or stretched greatly with a small bending rate. Moreover, according to the production method of the present invention, a thin gel coating film having a uniform, flexible and smooth surface can be obtained even when the glass transition temperature of the polymer of the water-soluble radical polymerizable monomer used exceeds 100 ° C. be able to. In contrast, a gel using only a known organic cross-linking agent without using the water-swellable clay mineral (B) cannot provide a homogeneous thin layer coating film from the slurry gel.

  Hereinafter, the present invention will be specifically described using examples. However, the present invention is not limited to the following examples.

(Example 1)
As a water-soluble radical polymerizable monomer, 5 g of N, N-dimethylacrylamide (DMAA, manufactured by Kojin Co., Ltd.) and 2 g of synthetic hectorite (trademark Laponite XLG) as a water-swellable clay mineral (clay mineral / DMAA = 0) .4) 47.5 g of ultrapure water (18 MΩ) and these were put into a 100 mL flask and stirred under a nitrogen atmosphere to obtain a homogeneous solution (K = 6.8 ). In addition, the ultrapure water used what bubbled nitrogen and substituted nitrogen. This solution was placed in an ice bath and stirred slowly for 10 minutes, and then 2.5 mL of a polymerization initiator aqueous solution consisting of 10 g of pure water prepared in advance and 0.2 g of potassium peroxodisulfide (KPS: manufactured by Kanto Chemical Co., Inc.) was added. Added under stirring. The polymerization liquid 1 was transferred to a 50 mL bottle, the inside was made into a nitrogen atmosphere, and the reaction was performed at 50 ° C. for 20 hours. The solution after polymerization was colorless and transparent, and the entire solution was gelled. (Process 1)
The gel was cut into a film having a thickness of about 5 mm, immersed in pure water, and held at 50 ° C. for 5 hours. The gel swelled and K = 42. (Process 2)
Further, pure water was added to the obtained swollen gel so that the total of the aqueous medium (Wc) in the gel and the water (D) to be added was {(Wc + D) / (W _A + W _B )} = 80. Then, the gel was pulverized with a mixer for cooking (Milcer IFM-700G, manufactured by Iwatani Corporation). The crushed gel was subjected to a defoaming process using a defoaming machine (AR-250, manufactured by Shinky Corporation). (Process 3)
The obtained slurry 1 was fluid and could be applied. Slurry 1 was applied to a glass plate with a thickness of about 0.7 mm and dried at 80 ° C. A dry coating of about 5 microns was obtained. The dried coating film was smooth.

The glass plate coated with the gel was immersed in pure water for 10 minutes. The dried coating film contained water and gelled. The gel was smooth. The film thickness was about 55 microns. When the dried coating film and the gel coating surface were observed with a microscope (Digital Microscope VHX-900 (manufactured by Keyence Corporation)), the surface was as shown in Photo 1 (FIG. 1) and Photo 2 (FIG. 2). All were smooth. A 3 × 3 cm ² metal plate (thickness 1 mm) was placed on the gel, and a 5 kg weight was placed thereon. The weight was removed and the place where pressure was applied was observed, but no difference was observed from the place where pressure was not applied. In the compression test, when the phenomenon of gel flow, large plastic deformation, or destruction occurs, “x” indicates that the phenomenon is obvious, “△” indicates that a clear deformation is observed, and the deformation is very The case where the difference is small is indicated by “◯”, and the case where there is almost no difference from the unpressurized place is indicated by “◎”. The results are summarized in Table 1. When the gel was peeled from the glass plate, an integrated gel thin film was obtained. The gel was not broken even when pulled strongly to 500%. When the strength of the gel is 500% or more, the case where it does not break is indicated by “◯”, the case where it breaks at 500% or less is indicated by “Δ”, and the case where it is broken at 100% or less is indicated by “X”.

  The dried coating film applied to the glass plate was immersed in an aqueous electrolyte solution of potassium hydroxide (1 mol / L) for 5 minutes to be re-contained. The gel coating after the liquid inclusion was smooth. The result of the compression test was “◯”. In addition, an electrolyte solution prepared by dissolving lithium hexafluorophosphate in γ-butyrolactone at a concentration of 0.5 mol / L and an electrolyte solution obtained by dissolving 1 mol / L adipic acid in ethylene glycol (EG) The applied dry gel was immersed for 5 minutes to obtain a re-swelled gel. All the re-swelled gel films were smooth. A compression test was performed. Butyrolactone was “◯” and EG was “◎”. When the gel was peeled from the glass plate, an integrated gel thin film was obtained. None of the gels were broken even when strongly pulled to 500%.

  Immerse the dried gel applied to the glass plate for 5 minutes in a 1/1 (mass ratio) solution of 1-butyl-3-methylimidazolium methyl sulfate (bmiMS) (manufactured by Fluka Co., Ltd.), which is an ionic liquid, and methanol. To obtain a re-swelled gel. The re-swelled gel was dried at 80 ° C. to obtain a gel containing an ionic liquid. The coating film was smooth. A compression test was performed. It was “◎”. When the gel was peeled from the glass plate, an integrated gel thin film was obtained. None of the gels were broken even when strongly pulled to 500%.

(Example 2)
A slurry 2 was produced in the same manner as in Example 1 except that montmorillonite (Kunipia F, manufactured by Kunimine Kogyo Co., Ltd.) was used as the water-swellable clay mineral instead of synthetic hectorite. However, K in step 2 was 37, and the amount of pure water (D) to be added was D / (W _A + W _B ) = 43. It applied to the glass plate like Example 1, it was set as the dry coating film, and was swollen with the pure water. The film thickness was about 45 microns. The results are summarized in Table 1.

Example 3
Example 1 except that 5.7 g of N, N-isopropylacrylamide (NIPA: manufactured by Kojin Co., Ltd.) was used as the water-soluble radical polymerizable monomer instead of DMAA, and 40 μL of tetramethylethylenediamine (TEMED) was used as the catalyst. A polymerization solution was prepared by the same method. The polymerization solution was kept at 20 ° C. for 20 hours to synthesize an organic-inorganic composite hydrogel (K = 6.2 ). The solution after polymerization was colorless and transparent, and the entire solution was gelled. (Process 1)
The hydrogel was cut to a thickness of about 5 mm to form a film. The cut gel was immersed in pure water and kept at 20 ° C. overnight to obtain a swollen gel (K = 30). (Process 2)
Further, pure water (D) was added so that D / (W _A + W _B ) = 30, and the gel was pulverized with a cooking mixer. The crushed gel was defoamed with a defoamer. (Process 3)
It apply | coated to the glass plate by the same method as Example 1, it was set as the dry coating film, and it was swollen with the pure water, and the re-swelling gel was obtained. The gel thickness was about 40 microns. The surface was excellent in smoothness. A compression test was performed, but the difference from the place where no pressure was applied was not seen, and it was good. Further, when the gel was peeled off from the glass plate and stretched, it could be stretched to 500% or more without breaking.

Example 4
Example 3 except that instead of DMAA, 4.6 g of 2-methoxyethyl acrylate (MEA: manufactured by Koa Gosei Co., Ltd.), 1.5 g of DMAA, and 2.0 g of synthetic hectorite were used as water-soluble radical polymerizable monomers. An organic-inorganic composite hydrogel was prepared by the same method.

The hydrogel was cut to a thickness of about 5 mm to form a film. The cut gel was immersed in 3 L of pure water and kept at 20 ° C. overnight to obtain a swollen gel (K = 45). (Process 2)
Furthermore, pure water (D) was added so that D / (W _A + W _B ) = 115, and the gel was pulverized with a cooking mixer. The crushed gel was defoamed with a defoamer. (Process 3)
It apply | coated to the glass plate by the same method as Example 1, it was set as the dry coating film, and it was swollen with the pure water, and the re-swelling gel was obtained. The gel thickness was about 20 microns. The surface was excellent in smoothness. A compression test was performed, but the difference from the place where no pressure was applied was not seen, and it was good. When the gel was peeled from the glass plate and stretched, it could be stretched to 500% or more without breaking. Further, in the same manner as in Example 1, a potassium hydroxide aqueous solution was again contained. The re-swelled gel was smooth and the compression test was “「 ”.

  In addition, the dry gel applied to the glass plate was immersed for 10 minutes in a non-aqueous electrolyte solution in which lithium hexafluorophosphate was dissolved at a concentration of 1 mol / L in a 1: 1 mixed solvent of dimethyl carbonate and ethylene carbonate in a weight ratio of 1: 1. Thus, a re-swelled gel was obtained. The re-swelled gel coating was smooth. The result of compressing the gel was also “◎”.

  A dry gel applied on a glass plate in a 1/1 (mass ratio) solution of 1-butyl-3-methylimidazolium hexafluorophosphate (bmiPF6) (manufactured by Fluka Co., Ltd.) and tetrahydrofuran as an ionic liquid for 5 minutes. A re-swelled gel was obtained by soaking. The re-swelled gel was dried at 80 ° C. to obtain a gel containing an ionic liquid. The coating film was smooth. The result of compressing the gel was “◎”. When the gel was peeled from the glass plate and stretched, it could be stretched to 500% or more without breaking.

(Comparative Example 1)
Example 1 except that 0.039 g of N, N′-methylenebis (acrylamide) (BIS) (special grade, manufactured by Wako Pure Chemical Industries, Ltd.) was used as the organic crosslinking agent instead of the water-swellable clay mineral. Slurry 2 was produced in the same manner. The organic cross-linked hydrogel obtained in step 1 was very brittle compared to the organic-inorganic composite gel. However, the amount of the organic cross-linking agent (BIS) used here is an optimum amount having strength as a gel. Although it applied to the glass plate by the same method as Example 1 and it was set as the dry coating film, as shown in the surface observation result photograph 3 (FIG. 3) of the dry coating film measured like Example 1, very much Deep cracks were observed, and a smooth coating film was not obtained. Moreover, although it was made to immerse in water like Example 1, the integrated homogeneous gel was not obtained. Further, the obtained heterogeneous gel was easily crushed when compressed, and the evaluation of the compression test was “x”. It was confirmed that in an ordinary organic cross-linked gel, the gel was finely pulverized to form a slurry and then an integrated gel coating film was not obtained even when applied.

(Comparative Example 2)
In Example 1, without performing Step 2, after Step 1, pure water (D) was added in Step 3 so that D / (W _A + W _B ) = 73, and the slurry was the same as in Example 1. Made. The particle size of the slurry was large. When this slurry was applied in the same manner as in Example 1, a non-uniform dry coating film with many spots on the surface was obtained. On the other hand, when the slurry was allowed to stand overnight, the particles swelled well due to water content, and a homogeneous slurry was obtained. When this slurry was applied to a glass plate in the same manner as in Example 1 and dried, a smooth dry gel was obtained. When the dried gel was rehydrated with water in the same manner as in Example 1, the surface of the rehydrated gel was uneven. The gel was peeled off but was not homogeneous. In the stretching test, it broke at about 200%.

(Example 5, Comparative Example 3)
In Example 4, an organic-inorganic composite hydrogel was produced in the same procedure as in Example 4 except that 5.4 g of MEA, 0.5 g of DMAA, and 0.8 g of synthetic hectorite were used.

  The hydrogel was cut to a thickness of about 5 mm to form a film.

As Example 5, the cut gel was immersed in 1/1 (mass ratio) of 3 L of water and ethanol, and kept at 20 ° C. overnight. The gel swelled and K was 25. On the other hand, as Comparative Example 3, the cut gel was immersed in 3 L of pure water and held at 15 ° C. for 1 day. The K of the swollen gel was 15. (Process 2)
In Example 5 and Comparative Example 3, the pure water (D) is further adjusted so that D / (W _A + W _B ) becomes 15 and 25, respectively ( _Wc + D) / (W _A + W _B ) } Were added 40) and pure water, and the gel was crushed with a mixer for cooking. The crushed gel was defoamed with a defoamer. (Process 3)
The same method as in Example 1 was applied to a glass plate to obtain a dry coating film, which was swollen in pure water to obtain a white turbid re-swelled gel. The gel thickness was about 15 microns.

  The gel of Example 5 was excellent in smoothness, but the gel of Comparative Example 3 was heterogeneous and non-uniform with spots appearing in some places. A compression test was performed, but the difference from the place where no pressure was applied was not seen, and it was good. When the gel was peeled from the glass plate and pulled, it was possible to stretch the gel of Example 5 to 500% or more, but the gel of Comparative Example 3 was broken by about 200% stretching.

  In addition, Example 5 was re-impregnated with an aqueous potassium hydroxide solution in the same manner as Example 1. The re-swelled gel was smooth and the compression test was “「 ”.

  In addition, the dry coating film of Example 5 was mixed with a non-aqueous electrolyte solution in which lithium hexafluorophosphate was dissolved at a concentration of 1 mol / L in a 1: 1 mixed solvent of dimethyl carbonate and ethylene carbonate, and applied to a glass plate. The applied dry gel was immersed for 10 minutes to obtain a re-swelled gel. The coating film of the re-swelled gel was smooth. The result of compressing the gel was “ゲ ル”.

(Example 6)
An organic-inorganic composite gel 1 was prepared by the same composition and method as in Example 1. The obtained gel was immersed in pure water (D1) and kept at 50 ° C. for 3 days. The gel swelled and K was 80.

  The swollen gel with K = 80 obtained in step 2 was pulverized as it was and defoamed with a defoaming machine. A highly viscous slurry was obtained. A gel coating was prepared in the same manner as in Example 1. The coating film was smooth. A compression test was conducted and the result was “◎”. Although the coating film was peeled off from the glass plate, it could be stretched to 500% or more.

(Comparative Example 4)
In Example 1, an organic-inorganic composite gel was synthesized by the same procedure as in Example 1 with 175 g of pure water at the time of polymerization (K = 25). A very weak gel was obtained. As a result of being immersed in pure water (D1) in the same manner as in Example 1, it swelled and K = 67. Further, pure water (D) was added so that D / (W _A + W _B ) = 13 (where (W _c + D) / (W _A + W _B )} was 80), and the gel was pulverized. The obtained slurry was fluid and could be applied. A dry coating film and a gel coating film were prepared in the same manner as in Example 1 to obtain a gel having a film thickness of about 55 microns. The gel was smooth. When the compression test was performed, a small deformation was observed “◯”. The gel was peeled from the glass plate. The gel was weak and broke up to 300% stretching. In the same manner as in Example 1, it was impregnated with potassium hydroxide. When the compression test was performed, a clear deformation was observed “Δ”. When the amount of water at the time of gel synthesis was increased (K = 25), it was confirmed that the mechanical properties were inferior.

(Comparative Example 5)
In Example 2, the gel of K = 37 was used after Step 2, and only the gel of K = 37 was pulverized without adding water (D2) in Step 3. The gel was pulverized small, but the crushed gel became a lump and could not be applied.

Claims (5)

Dissolve or disperse the water-soluble radically polymerizable monomer (A) having one (meth) acrylamide group or (meth) acryloyloxy group in the molecule and the water-swellable clay mineral (B) in the aqueous medium (C). And the aqueous solution whose mass ratio (K) of the aqueous medium (C) represented by following formula (1) is 3-15 is manufactured, In this case, the water swelling with respect to the said water-soluble radically polymerizable monomer (A) The ratio (W _B / W _A ) of the mass of the porous clay mineral (B ) is 0.03 to 2.0,
Step 1 of obtaining an organic-inorganic composite gel by polymerizing the water-soluble radical polymerizable monomer (A) in the aqueous solution,
Step 2 of swelling the organic-inorganic composite gel in water so that (K) is 40 to 200,
Step 3 of pulverizing the swollen organic-inorganic composite gel,
The manufacturing method of the slurry-like organic inorganic composite gel obtained by this.
Formula (1) (K) = W _C / (W _A + W _B )
(W _C represents the mass of the aqueous medium (C), W _A represents the mass of the water-soluble radical polymerizable monomer (A), and W _B represents the mass of the water-swellable clay mineral (B).) Dissolve or disperse the water-soluble radically polymerizable monomer (A) having one (meth) acrylamide group or (meth) acryloyloxy group in the molecule and the water-swellable clay mineral (B) in the aqueous medium (C). And the aqueous solution whose mass ratio (K) of the aqueous medium (C) represented by following formula (1) is 3-15 is manufactured, In this case, the water swelling with respect to the said water-soluble radically polymerizable monomer (A) The ratio (W _B / W _A ) of the mass of the porous clay mineral (B ) is 0.03 to 2.0,
Formula (1) (K) = W _C / (W _A + W _B )
(W _C represents the mass of the aqueous medium (C), W _A represents the mass of the water-soluble radical polymerizable monomer (A), and W _B represents the mass of the water-swellable clay mineral (B).)
Step 1 of obtaining an organic-inorganic composite gel by polymerizing the water-soluble radical polymerizable monomer (A) in the aqueous solution,
Step 2 of swelling the organic-inorganic composite gel in water so that (K) is 25 to 100,
Furthermore, Step 3 is performed by adding water (D) to the swollen organic-inorganic composite gel so that {(W _C + D) / (W _A + W _B )} is 40 to 200, and crushing.
The manufacturing method of the slurry-like organic inorganic composite gel obtained by this.   The manufacturing method of the organic inorganic composite gel coating film obtained by apply | coating the slurry-like organic inorganic composite gel of Claim 1 or 2 to a base material, making it dry, and then impregnating a medium (E).   The method for producing an organic-inorganic composite gel coating film according to claim 3, wherein the medium (E) contains a solute (F).   The method for producing an organic-inorganic composite gel coating film according to claim 4, wherein the solute (F) is an electrolyte or a salt.

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