JP2009155657A - Polymer gel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide gel which swells more greatly in oil-absorptive gel. <P>SOLUTION: The gel is polymer gel which has any one sort of quaternary ammonium, quaternary phosphonium, quaternary pyridinium and quaternary imidazolinium which have anions with low ligating property or high hydrophobic property as counter anions. The length of long-chain alkyl of the quaternary ammonium, quaternary phosphonium, quaternary pyridinium or quaternary imidazolinium is lengthened to enlarge the degree of swelling in an organic solvent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polymer gel, and particularly to a polymer gel exhibiting large swelling in an organic solvent.

  Conventionally, a highly water-absorbing gel that swells by absorbing water several hundred times its own weight has been used as a water retaining agent or a water absorbent such as a disposable diaper.

  In such a superabsorbent gel, a large amount of the gel in the gel is utilized by utilizing the osmotic pressure resulting from the difference in charge density caused by the dissolution of the salt bound to the polymer chain constituting the gel into water. It shows a large swelling by taking in water.

  Furthermore, in recent years, in order to facilitate disposal of the water-absorbing water-absorbing gel, for example, carboxymethyl starch (CMS) and starch are blended, and after adding water and kneading to form a paste, ionizing radiation is emitted. A superabsorbent starch gel produced by irradiation is also known (see, for example, Patent Document 1).

  In addition, a polymer gel composed of a resin having an oil-absorbing property has been proposed. For example, a polymer gel formed of an oil-absorbing resin, a polybutene that is a base oil, and an alkyl-modified silicone oil that is compatible with the polybutene. The polymer gel is used as an ink follower for writing instruments (see, for example, Patent Document 2).

JP 2003-048997 A JP 2002-274094 A

  However, the conventional gel having oil absorbency absorbs oil by causing swelling by utilizing the compatibility with the solvent of the polymer chain constituting the gel, and the absorption amount is small and larger. There has been a need for gels that swell and become highly absorbent.

  Accordingly, the present inventors have conducted research to develop a gel that swells more greatly in an oil-absorbing gel, and have achieved the present invention.

In the polymer gel of the present invention, any one of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, and quaternary imidazolinium having an anion having a low coordination property or a high hydrophobicity as a counter anion , It was set as the polymer gel which has.

In the polymer gel of the present invention, any one of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, and quaternary imidazolinium having an anion having low coordination or high hydrophobicity, copolymerizable monomers, and crosslinking agent, and a polymer gel consisting of.

Furthermore, the polymer gel of the present invention is also characterized by the following points. That is,
(1) Anions with low coordination or high hydrophobicity are bromine anion, iodine anion, trifluoromethaneacetate anion, fluorosulfonate anion, trifluoromethanesulfonate anion, bis (trifluoromethanesulfonyl) imide anion, tetraphenylborate Anion, Tetrakis (4-chlorophenyl) borate anion, Tetrakis (4-fluorophenyl) borate anion, Perfluorotetraphenylborate anion, Tetrakis [3,5-bis (trifluoromethyl) -phenyl] borate anion, Tetrafluoroborate anion , A perchlorate anion, a hexafluorophosphate anion, a hexafluoroantimonate anion, a carborate anion, and a derivative anion thereof.
(2) The length of the long chain alkyl of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, or quaternary imidazolinium is increased to increase the degree of swelling in an organic solvent.
(3) The main chain of the copolymerization monomer is lengthened to increase the degree of swelling in the organic solvent.
(4) The distribution amount of the crosslinking agent was reduced to increase the degree of swelling in the organic solvent.
(5) The distribution amount of the crosslinking agent is increased to increase the hardness.

According to the first aspect of the present invention, any one of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, and quaternary imidazolinium having an anion having low coordination or high hydrophobicity as a counter anion. By using a polymer gel having one kind , it is possible to provide a polymer gel that exhibits high absorbability with respect to an organic solvent and swells greatly.

According to the invention of claim 2, any one of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, and quaternary imidazolinium having an anion having low coordination or high hydrophobicity, By using a polymer gel comprising a copolymerization monomer and a crosslinking agent , a polymer gel that exhibits high absorbability with respect to an organic solvent and swells greatly can be provided.

  According to the invention described in claim 3, in the polymer gel according to claim 1 or 2, the anion having a low coordination property or a high hydrophobic property is selected from a bromine anion, an iodine anion, a trifluoromethaneacetate anion, a fluoro Sulfonate anion, trifluoromethanesulfonate anion, bis (trifluoromethanesulfonyl) imide anion, tetraphenylborate anion, tetrakis (4-chlorophenyl) borate anion, tetrakis (4-fluorophenyl) borate anion, perfluorotetraphenylborate anion, Tetrakis [3,5-bis (trifluoromethyl) -phenyl] borate anion, tetrafluoroborate anion, perchlorate anion, hexafluorophosphate anion, hexafluoroantimonate anion, carborane acid anion By using one kind selected from nion and its derivative anion, it is possible to provide a relatively inexpensive polymer gel that exhibits high absorbability to organic solvents and swells greatly.

  According to invention of Claim 4, in the polymer gel of any one of Claims 1-3, quaternary ammonium, quaternary phosphonium, quaternary pyridinium, or quaternary imidazolinium. By increasing the length of the long-chain alkyl, it is possible to provide a polymer gel exhibiting higher absorbability to the organic solvent by increasing the degree of swelling in the organic solvent.

  According to the invention of claim 5, in the polymer gel of claim 2, by increasing the length of the main chain of the copolymerization monomer, the degree of swelling in the organic solvent is increased to be higher than that of the organic solvent. A polymer gel exhibiting absorbability can be provided.

  According to the invention described in claim 6, in the polymer gel according to claim 2 or 5, the distribution amount of the crosslinking agent is reduced to increase the degree of swelling in the organic solvent. On the other hand, it is possible to provide a polymer gel showing higher absorbability.

  According to the seventh aspect of the present invention, in the polymer gel according to the second or fifth aspect, the degree of swelling in the organic solvent is slightly increased by increasing the distribution amount of the crosslinking agent and increasing the hardness. Although reduced, a polymer gel having a predetermined shape can be provided.

It is a graph which shows the evaluation result of the swelling degree of Octd gel and THA-TFPB-co-Octd 5/95 gel with respect to various solvents. It is a graph which shows the evaluation result of the swelling degree of EH gel and THA-TFPB-co-EH 5/95 gel with respect to various solvents.

  The polymer gel of the present invention comprises any one of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, and quaternary imidazolinium having a counter-anion having a low coordination or high hydrophobic anion. It has a polymer gel. Here, “highly hydrophobic” is synonymous with “highly lipophilic” or “lowly hydrophilic”.

  That is, the oil absorption in the polymer gel is not based on the compatibility with the solvent of the polymer chain constituting the gel, but the salt bonded to the polymer chain constituting the gel is replaced with an organic material such as oil. Dissolving in a solvent causes a difference in charge density, and a large amount of organic solvent is incorporated into the gel using the osmotic pressure resulting from the difference in charge density, thereby enabling large swelling. is there.

  That is, by providing an anion having a low coordination property or a high hydrophobicity as a counter anion, an anion having a low coordination property or a high hydrophobicity can be easily released in an organic solvent. A large amount of organic solvent is taken into the gel using osmotic pressure resulting from the difference in charge density caused by liberation.

  Thus, by using the osmotic pressure resulting from the difference in charge density caused by the liberation of anions, it was generated using the compatibility of the polymer chain constituting the gel with the organic solvent as in the past. Although the maximum swelling is about 30 times its own weight, it can be improved to about 80 to 130 times.

  In particular, a low-coordinating or highly-hydrophobic anion is selected from bromine anion, iodine anion, trifluoromethaneacetate anion, fluorosulfonate anion, trifluoromethanesulfonate anion, bis (trifluoromethanesulfonyl) imide anion, tetraphenylborate anion. Tetrakis (4-chlorophenyl) borate anion, tetrakis (4-fluorophenyl) borate anion, perfluorotetraphenylborate anion, tetrakis [3,5-bis (trifluoromethyl) -phenyl] borate anion, tetrafluoroborate anion, By using one kind selected from perchlorate anion, hexafluorophosphate anion, hexafluoroantimonate anion, carborate anion and its derivative anion, The polymer gel exhibits high absorbability with respect to the medium, is hardly affected by environmental conditions such as air temperature and humidity, and can be a relatively inexpensive polymer gel.

  In addition, quaternary ammonium, quaternary phosphonium, quaternary pyridinium, or quaternary imidazolinium each have a long-chain alkyl. By making the length of this long-chain alkyl as long as possible, the lipophilicity can be increased. The degree of swelling in an organic solvent can be increased, and a polymer gel showing higher absorbability with respect to the organic solvent can be obtained. Thus, in order to improve lipophilicity, it is desirable that the long-chain alkyl has a length of C6 or more.

  On the other hand, when the long-chain alkyl is shortened, the hydrophilicity can be improved, so that the degree of swelling with respect to water or alcohol can be improved.

  In particular, the polymer gel of the present invention includes any one of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, and quaternary imidazolinium having an anion having low coordination or high hydrophobicity, Consists of a copolymerization monomer and a crosslinking agent. Not only can the lipophilicity and hydrophilicity be adjusted by adjusting the length of the long-chain alkyl, but also the lipophilicity and hydrophilicity can be adjusted by adjusting the length of the copolymerized monomer. Can be adjusted.

  That is, when the main chain of the copolymerization monomer is lengthened, the lipophilicity can be improved, so that the degree of swelling with respect to a low polarity solvent such as an organic solvent can be improved. In order to improve lipophilicity, it is desirable that the main chain of the copolymerization monomer has a length of C6 or more.

  On the other hand, when the main chain of the copolymerization monomer is shortened, the lipophilicity can be improved, so that the degree of swelling with respect to a highly polar solvent such as water or alcohol can be improved.

  Here, as the copolymerization monomer, vinyl chloride, acrylic acid derivative, methacrylic acid derivative, acrylonitrile, methacrylonitrile, styrene derivative, butadiene, ethylene, propylene, isoprene, vinylpyridine derivative, and the like can be used.

  Furthermore, the hardness of the polymer gel can be adjusted by adjusting the distribution amount of the cross-linking agent, and when the distribution amount of the cross-linking agent is reduced, the polymer gel should be in a soft state with high deformability. And deformation due to absorption of the organic solvent can be facilitated, so that a polymer gel having a high degree of swelling in the organic solvent and high absorbability to the organic solvent can be obtained.

  On the other hand, when the distribution amount of the cross-linking agent is increased, the polymer gel is in a hard state in which the deformability is small, so that resistance to deformation due to absorption of the organic solvent is likely to increase, and swelling in the organic solvent is inhibited. The Rukoto. Therefore, the absorption amount of the organic solvent by the polymer gel can be easily adjusted by adjusting the distribution amount of the crosslinking agent.

  In this example, a quaternary ammonium cation having a long-chain alkyl and a tetrakis [3,5-bis (trifluoromethyl) -phenyl] borate anion which is a low-coordination or high-hydrophobic anion as a counter anion (Tetrakis [3,5-bis (trifluoromethy) -phenyl] borate (TFPB)) was used to prepare a polymer electrolyte gel into which a hydrophobic ion pair THA-TFPB was introduced. Instead of quaternary ammonium, quaternary phosphonium, quaternary pyridinium, or quaternary imidazolinium may be used.

  The hydrophobic ion pair THA-TFPB was prepared based on the following chemical formula.

すなわち、三角フラスコにTetrakis[3,5-bis(l)-phenyl]borate,sodium salt dehydrate(1.47g,1.66mmol)を入れてメタノール−水混合溶媒に溶解させ、この溶液にTHA-Br(0.74g,1.60mmol)のメタノール−水混合溶媒を加えて室温にて撹拌した。１２時間後に沈殿をろ別し、メタノール−水混合溶媒で固液洗浄して減圧乾燥して生成した。収量は1.36g（収率６８％）であった。¹H-NMRによる同定結果を下表に示す。

That is, Tetrakis [3,5-bis (l) -phenyl] borate, sodium salt dehydrate (1.47 g, 1.66 mmol) was placed in an Erlenmeyer flask and dissolved in a methanol-water mixed solvent, and THA-Br (0.74 g, 1.60 mmol) of methanol-water mixed solvent was added, and the mixture was stirred at room temperature. After 12 hours, the precipitate was filtered off, washed with a solid-liquid mixture with a methanol-water mixed solvent, and dried under reduced pressure to produce. The yield was 1.36 g (68% yield). ^The identification results by ¹ H-NMR are shown in the table below.

第１のサンプルとして、疎水性イオン対THA-TFPBと、中性モノマーであるオクタデシルアクリレート(Octd)との架橋共重合体(THA-TFPB-co-Octd gel)を生成した。すなわち、THA-TFPB-co-Octd gelは、以下の化学式に基づいて作成した。

As a first sample, a crosslinked copolymer (THA-TFPB-co-Octd gel) of a hydrophobic ion pair THA-TFPB and a neutral monomer octadecyl acrylate (Octd) was produced. That is, THA-TFPB-co-Octd gel was prepared based on the following chemical formula.

また、第２のサンプルとして、疎水性イオン対THA-TFPBと、２エチルヘキシルアクリルレート(EH)との架橋共重合体(THA-TFPB-co-EH gel)を生成した。すなわち、THA-TFPB-co-EH gelは、以下の化学式に基づいて作成した。

As a second sample, a crosslinked copolymer (THA-TFPB-co-EH gel) of a hydrophobic ion pair THA-TFPB and 2-ethylhexyl acrylate (EH) was produced. That is, THA-TFPB-co-EH gel was prepared based on the following chemical formula.

特に、第１のサンプル及び第２のサンプルでは、それぞれ下表に示す条件で、疎水性イオン対THA-TFPBの有無のサンプルを作成した。すなわち、第１のサンプルで疎水性イオン対THA-TFPBを含有しないOctd gelと、中性モノマー（Octd）に対して仕込み比で疎水性イオン対THA-TFPBを５％導入したTHA-TFPB-co-Octd 5/95 gelと、第２のサンプルで疎水性イオン対THA-TFPBを含有しないEH gelと、中性モノマー（EH）に対して仕込み比で疎水性イオン対THA-TFPBを５％導入したTHA-TFPB-co-EH 5/95 gelとを作成した。

In particular, in the first sample and the second sample, samples with or without the hydrophobic ion pair THA-TFPB were prepared under the conditions shown in the following table, respectively. That is, Octa gel containing no hydrophobic ion pair THA-TFPB in the first sample and THA-TFPB-co containing 5% of hydrophobic ion pair THA-TFPB in a charge ratio with respect to neutral monomer (Octd) -Octd 5/95 gel, EH gel that does not contain hydrophobic ion pair THA-TFPB in the second sample, and 5% of hydrophobic ion pair THA-TFPB at a charge ratio to neutral monomer (EH) THA-TFPB-co-EH 5/95 gel was prepared.

上記のサンプル作成では、表２に示した条件でそれぞれ調整したサンプルをアンプル管に入れて脱気封管し、６０℃で２４時間加熱し、ゲル化させた。ゲル化後、アンプル管を割ることにより均一な円柱状のゲルを得て、バキュームオーブンにて乾燥し、直径４ｍｍ、厚み約１ｍｍの円盤状に切断した。

In the above sample preparation, the samples adjusted under the conditions shown in Table 2 were put in an ampule tube, degassed and sealed, and heated at 60 ° C. for 24 hours to be gelled. After gelation, the ampule tube was broken to obtain a uniform columnar gel, dried in a vacuum oven, and cut into a disk having a diameter of 4 mm and a thickness of about 1 mm.

Thus, the weight of the disk-shaped dry gel was measured, and an excess solvent was added to the dry gel and left to reach an equilibrium state, and the weight of the swollen gel swollen by absorbing the solvent was measured. Here, the dry gel weight is W _dry , the swollen gel weight is W _wet , and the difference between the swollen gel weight and the dry gel weight (W _wet −W _dry ) is the amount of solvent absorbed by the dry gel. Calculated.

  Furthermore, the degree of swelling Sw was defined by the following formula.

Sw = (W _wet -W _dry ) / W _dry
Octd gel and THA-TFPB-co-Octd 5/95 when the solvent is hexane (Hexane), toluene (Toluene), chloroform (Chloroform), chlorobenzene (ChloroBenzene), tetrahydrofuran (THF), dichloromethane (Dichloromethane) The evaluation result of the degree of swelling of the gel is shown in the graph of FIG.

  In the Octd gel not containing the hydrophobic ion pair THA-TFPB, the swelling degree is about 20 times, whereas in the THA-TFPB-co-Octd 5/95 gel containing the hydrophobic ion pair THA-TFPB, It can be seen that the degree of swelling is about 60 times or more. Note that THA-TFPB-co-Octd 5/95 gel did not show any improvement in the degree of swelling in hexane and toluene, but this did not cause much dissociation of the hydrophobic ion pair THA-TFPB in hexane and toluene. This is probably because the osmotic pressure due to the difference in charge density did not occur because the difference in charge density did not occur.

  As shown in FIG. 1, when the blending amount of ethylene glycol dimethacrylate (EGDMA) used as a crosslinking agent is about 1%, THA-TFPB-co-Octd 5/95 gel has a swelling degree of 84 times in chloroform, The swelling degree in tetrahydrofuran is 77 times and the swelling degree in dichloromethane is 137 times. However, when the amount of the crosslinking agent is about 0.5%, the swelling degree in chloroform is 144 times, and the swelling degree in tetrahydrofuran is 163. The swelling degree in dichloromethane is 188 times, and when the amount of the crosslinking agent is about 0.2%, the swelling degree in chloroform is 297 times, the swelling degree in tetrahydrofuran is 384 times, and the swelling degree in dichloromethane Was 482 times.

  That is, it can be seen that THA-TFPB-co-Octd 5/95 gel can improve the degree of swelling by reducing the crosslinking density.

  When the solvent is toluene (Toluene), tetrahydrofuran (THF), dichloromethane (Dichloromethane), acetone (Acetone), n-Butyronitrile, EH gel and THA-TFPB-co-EH 5/95 The evaluation result of the degree of swelling of the gel is shown in the graph of FIG.

  In the EH gel not containing the hydrophobic ion pair THA-TFPB, the swelling degree is 10 times or less, whereas in the THA-TFPB-co-EH 5/95 gel containing the hydrophobic ion pair THA-TFPB, It can be seen that the degree of swelling is about 45 times or more. In THA-TFPB-co-EH 5/95 gel, toluene did not improve the degree of swelling, but in toluene, the dissociation of hydrophobic ions versus THA-TFPB did not occur so much, and the difference in charge density was not observed. This is probably because the osmotic pressure due to the difference in charge density did not occur.

  Since the polymer gel of the present invention exhibits a large swelling with respect to an organic solvent, it can be used not only as a high-performance oil fence, but also as an adsorbent or a solidifying agent for use in disposal of edible oil. It can also be used as a solidifying agent for solidifying and storing the solvent.

Claims (7)

Quaternary ammonium having coordinating low or highly hydrophobic anion as a counter anion, quaternary phosphonium, quaternary pyridinium, any one of the quaternary imidazolinium, polymer gel having. Quaternary ammonium having coordinating low or highly hydrophobic anions, quaternary phosphonium, quaternary pyridinium, and any one of the quaternary imidazolinium, copolymerizable monomers, the crosslinking agent, A polymer gel.   The low-coordination or high-hydrophobic anion includes bromine anion, iodine anion, trifluoromethaneacetate anion, fluorosulfonate anion, trifluoromethanesulfonate anion, bis (trifluoromethanesulfonyl) imide anion, tetraphenylborate anion. Tetrakis (4-chlorophenyl) borate anion, tetrakis (4-fluorophenyl) borate anion, perfluorotetraphenylborate anion, tetrakis [3,5-bis (trifluoromethyl) -phenyl] borate anion, tetrafluoroborate anion, A perchlorate anion, a hexafluorophosphate anion, a hexafluoroantimonate anion, a carborate anion and a derivative anion thereof, Item 5. The polymer gel according to Item 1 or Item 2.   The long-chain alkyl of the quaternary ammonium, quaternary phosphonium, quaternary pyridinium, or quaternary imidazolinium is lengthened to increase the degree of swelling in an organic solvent. The polymer gel according to any one of claims 1 to 3.   The polymer gel according to claim 2, wherein the main chain of the copolymerization monomer is lengthened to increase the degree of swelling in an organic solvent.   6. The polymer gel according to claim 2, wherein the distribution amount of the crosslinking agent is reduced to increase the degree of swelling in an organic solvent.   The polymer gel according to claim 2, wherein the distribution amount of the crosslinking agent is increased to increase the hardness.

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