JP2015044923A - Method for manufacturing beta polyketone, beta polyketone, method for manufacturing specified metal ion extractant and specified metal ion extractant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide novel availability of PVA as a reactant (raw material) and to provide a novel functional material.SOLUTION: The problem is solved by a method for manufacturing beta polyketone including oxidation of polyvinyl alcohol to obtain beta polyketone, beta polyketone obtained by the manufacturing method, a method for manufacturing a specified metal ion extractant including oxidation of polyvinyl alcohol to obtain a specified metal ion extractant, and the specified metal ion extractant obtained by the method for manufacturing the specified metal ion extractant.

Description

  The present invention relates to a method for producing a beta polyketone in which polyvinyl alcohol (PVA) can be used as a raw material, a method for producing a beta polyketone, a specific metal ion extractant, and a specific metal ion extractant.

  PVA is a typical reaction product of a polymer compound. For example, PVA can be obtained as a reaction product by a reaction of saponifying polyvinyl acetate obtained by polymerizing a vinyl acetate monomer.

  PVA is used, for example, as a polarizing film raw material for liquid crystal screens, a fiber or paper processing agent, an adhesive for woodwork bond or plywood, a polymerization additive for polyvinyl chloride, an intermediate film raw material for an automobile windshield, and the like.

  Industrially, PVA is often used as it is as a reaction product, and there are few examples of using it for further reaction.

  As an example of subjecting PVA to further reaction, there is an acetalization reaction for producing vinylon and polyvinyl butyral from PVA.

  Patent Document 1 discloses reacting PVA with a trihalosilane compound having a fluorine-containing long-chain alkyl group in order to reduce the hydrophilicity of the solid surface of PVA.

  Furthermore, Patent Document 2 discloses a main chain cleavage reaction of PVA using an oxidizing agent as a method for reducing the degree of polymerization of PVA.

  Attempts to use PVA as a reactant (raw material) or to increase its functionality are as described above, and have not been sufficiently studied. One reason for this is that PVA is a highly stable polymer (in other words, poor reactivity).

JP 11-322986 A JP 2000-86992 A

  As a result of diligent research, the present inventor has paid attention to PVA as a reactant (raw material), and as a result, a reaction that oxidizes this can occur, and a beta polyketone that is a product obtained by such an oxidation reaction is newly introduced. It has been found that it shows promising properties as a functional material.

  Then, the subject of this invention is providing the new availability of PVA as a reaction material (raw material).

  Another object of the present invention is to provide a new functional material.

  Still other problems of the present invention will become apparent from the following description.

  The above problems are solved by the following inventions.

(Claim 1)
A method for producing beta polyketone, characterized in that beta polyketone is obtained by oxidizing polyvinyl alcohol.

(Claim 2)
The method for producing a beta polyketone according to claim 1, wherein the polyvinyl alcohol is oxidized using an oxidizing agent.

(Claim 3)
The method for producing beta polyketone according to claim 2, wherein nitrogen oxide is used as the oxidizing agent.

(Claim 4)
The method for producing a beta polyketone according to claim 3, wherein nitrogen dioxide and / or dinitrogen tetroxide is used as the nitrogen oxide.

(Claim 5)
A beta polyketone obtained by the method for producing a beta polyketone according to claim 1.

(Claim 6)
The beta polyketone according to claim 5, which exhibits IR absorption derived from keto type and / or enol type.

(Claim 7)
The beta polyketone according to claim 6, wherein the IR absorption appears at 1710 to 1725 cm ⁻¹ and / or 1620 to 1655 cm ⁻¹ .

(Claim 8)
The beta polyketone according to any one of claims 5 to 7, comprising a plurality of oxoethylene units represented by the following (1).

(Claim 9)
A method for producing a specific metal ion extractant, comprising obtaining a specific metal ion extractant by oxidizing polyvinyl alcohol.

(Claim 10)
The method for producing a specific metal ion extractant according to claim 9, wherein the polyvinyl alcohol is oxidized using an oxidizing agent.

(Claim 11)
The method for producing a specific metal ion extractant according to claim 10, wherein nitrogen oxide is used as the oxidant.

(Claim 12)
The method for producing a specific metal ion extractant according to claim 11, wherein nitrogen dioxide and / or dinitrogen tetroxide is used as the nitrogen oxide.

(Claim 13)
A specific metal ion extractant obtained by the method for producing a specific metal ion extractant according to claim 9.

(Claim 14)
The specific metal ion extractant according to claim 13, which exhibits IR absorption derived from keto type and / or enol type.

(Claim 15)
The specific metal ion extractant according to claim 14, wherein the IR absorption appears at 1710 to 1725 cm ^-1 and / or 1620 to 1655 cm ^-1 .

(Claim 16)
The specific metal ion extractant according to any one of claims 13 to 15, which has an extraction ability for palladium ions.

  According to the present invention, new availability of PVA as a reactant (raw material) can be provided.

  Moreover, according to this invention, a new functional material can be provided.

The figure which shows the result of an Example (IR spectrum of beta polyketone) The figure which shows the result of an Example (UV spectrum of a beta polyketone)

  The “beta polyketone” as used in the present invention is a general term that can include keto-enol tautomers of beta polyketone.

  A keto-type beta polyketone is a compound having a structure in which a carbonyl group is adjacent via one carbon atom. That is, it has a structure in which the next carbonyl group is located in the beta position as seen from one carbonyl group.

  Examples of the keto-type beta polyketone include compounds having the structure represented by the following (2) (multiple repeating oxoethylene units).

(However, n is an integer of 2 or more.)

  The enol-type beta polyketone refers to one in which at least a part of the carbonyl group (keto group) of the keto-type beta polyketone described above is changed to an enol (keto-enol tautomerism), which will be described in detail later.

  Conventionally, as a polyketone, an alternating copolymer of olefin and carbon monoxide has been studied as a new engineering plastic (review: Chem. Rev., 1996, 663, JP 2013-76024 A). This copolymer has 1-oxotrimethylene as a repeating unit, and since there are two carbons between carbonyl groups, it is a gamma polyketone in which the next carbonyl group is located in the third, that is, gamma, position from the carbonyl group. is there.

  There are almost no examples of beta polyketone used in industry. Only acetylacetone is commercially available as a reagent. (The IUPAC name for acetylacetone is 2,4-pentanedione, a beta diketone in which there is one carbon between two carbonyl groups and the second carbonyl group is located in the beta position, ie, the second carbonyl group. In other words, it can be regarded as a kind of beta polyketone (in the case of n = 2 in the above (2)). In other cases, beta triketones having three carbonyl groups have been reported as natural product synthetic intermediates (Chem. Pharm. Bull., 28, 2460 (1980)). There is no reported example of a beta polyketone with n of 5 or more.

  The method for producing a beta polyketone according to the present invention is a novel production method, and is particularly preferably used in the case of producing not only a beta polyketone having 2 or 3 but also a beta polyketone having a relatively large molecular weight, wherein n is 4 or more. be able to.

  The beta polyketone having n of 4 or more provided for the first time by the present invention has various possibilities as a functional material, and will be described in detail later. For example, it has excellent ability as a specific metal ion extractant.

  Moreover, when implementing this invention, PVA which can be obtained comparatively easily can be utilized as a raw material, for example. In one aspect, the present invention can also be said to provide new availability of PVA.

  Below, the form for implementing this invention is demonstrated in detail.

  In the method for producing a beta polyketone of the present invention, PVA can be used as a raw material. PVA is also used as a laundry glue and can be easily obtained.

  PVA is not particularly limited, and a commercially available product can also be used. For example, a compound having a structure (multiple repeating structures of vinyl alcohol units) shown in (3) below can be preferably exemplified.

  The number of repeating vinyl alcohol units n is not particularly limited as long as it is 2 or more, but is preferably 3 or more, and more preferably 4 or more. From the viewpoint of using the product (beta polyketone) produced by the production method of beta polyketone as a functional polymer, n is preferably 10 or more, more preferably 50 or more, and most preferably 100 or more.

  The degree of saponification of PVA is not particularly limited. However, when the degree of saponification is extremely low, the probability that a ketone is formed at the beta position decreases, and polybetaketone may not be easily generated. The degree of saponification of PVA is preferably 50 mol% or more, and more preferably 98 mol% or more. Here, the degree of saponification refers to the degree of saponification from polyvinyl acetate (PVAc) which is a raw material of PVA.

  In the present invention, PVA is preferably subjected to the reaction in the form of a solid. The shape of the solid is not particularly limited, and can be subjected to the reaction in various shapes such as a film shape, a linear shape, a fiber shape (cloth shape), a plate shape, a pellet shape, a powder shape, or an arbitrary molded body. (In the following description, the film form may be mainly described. However, this is only selected from the viewpoint that the product can be easily analyzed, and does not limit the present invention. Absent.)

  Further, all of PVA does not necessarily have to be changed to beta polyketone by an oxidation reaction described later, and at least a part of PVA may be changed. For example, when the PVA is subjected to the reaction in a solid state, for example, only the surface may be changed to beta polyketone so as to leave an unaltered portion in the inner layer.

  In PVA, both ends of a structure in which a plurality of vinyl alcohol units are repeated may each be a hydrogen atom, or may be substituted with an arbitrary substituent.

  In the present invention, the synthesis reaction of beta polyketone can proceed regardless of whether or not the terminal of PVA has a substituent. To give an extreme example, for example, the synthesis reaction of beta polyketone, even when the end of PVA is used directly or via an arbitrary linking group and fixed to the substrate surface (for example, a monomolecular film). Can be advanced.

  In the present invention, a compound in which some or all of the hydroxyl atoms in the vinyl alcohol unit of PVA described above are substituted with an arbitrary substituent (such as an alkyl group or an aryl group) is also used as a raw material. Can do. Such compounds are not particularly limited, but preferred examples include ethylene vinyl alcohol copolymers and vinyl alcohol / aromatic vinyl copolymers.

  In the present invention, the raw materials may be used alone or in combination of two or more.

  In this invention, beta polyketone is obtained by oxidizing (oxidation reaction) the raw material demonstrated above.

  In the present invention, the conditions for the oxidation reaction are not particularly limited as long as beta polyketone can be produced, and can be set as appropriate.

  When oxidizing the raw material, it is preferable to use an oxidizing agent.

  Although it does not specifically limit as an oxidizing agent, A nitrogen oxide etc. can be illustrated preferably.

Nitrogen oxide is not particularly limited, but nitric oxide (NO), nitrogen dioxide (NO ₂ ), nitrous oxide (dinitrogen monoxide) (N ₂ O), dinitrogen trioxide (N ₂ O ₃ ). , Dinitrogen tetroxide (N ₂ O ₄ ), dinitrogen pentoxide (N ₂ O ₅ ) and the like can be preferably exemplified, and in particular, NO ₂ and / or N ₂ O ₄ is preferably used.

NO ₂ and N ₂ O ₄ coexist in an equilibrium relationship (2NO ₂ ⇔N ₂ O ₄ ). This equilibrium balance can be easily controlled by adjusting temperature and pressure. When the temperature is increased, the equilibrium is inclined to NO ₂ , and when the pressure is increased, the equilibrium is inclined to dinitrogen tetroxide N ₂ O ₄ .

There is a difference in oxidizing power between N ₂ O ₄ and NO ₂ . N ₂ O ₄ has a relatively mild oxidizing power, and NO ₂ shows a stronger oxidizing power.

In the present invention, oxidation of a hydroxyl group (or a group in which a hydrogen atom of the hydroxyl group is substituted by a substituent) is allowed to proceed in a state in which the main chain of the raw material polymer is prevented from being cleaved by oxidation (oxidative cleavage). preferable. From such a point of view, it is preferable to carry out the oxidation reaction in a state where the equilibrium is inclined to N ₂ O ₄ whose oxidizing power is relatively mild.

The amount of NO ₂ and / or N ₂ O ₄ used is preferably 0.1 to 200 times, and 0.8 to 100 times, per mole of hydroxyl group of the PVA repeating unit (vinyl alcohol unit). More preferably, it is a mole, and most preferably 1.0 to 50 times mole. The number of moles referred to here is the number of moles of NO ₂ and / or N ₂ O ₄ converted to NO ₂ (N ₂ O ₄ is regarded as two molecules of NO ₂ ).

Hereinafter, preferable reaction conditions for the oxidation reaction in the present invention will be described in detail by way of an example in which NO ₂ and / or N ₂ O ₄ is used as an oxidizing agent.

The temperature of the oxidation reaction is preferably 150 ° C. or lower, more preferably 100 ° C. or lower, and most preferably 50 ° C. or lower from the viewpoint of increasing the proportion of N ₂ O ₄ exhibiting a suitable oxidizing power. . When the reaction temperature exceeds 150 ° C., the ratio of NO ₂ increases, the main chain of the raw material (polymer) is easily cleaved, and the resulting beta polyketone may be reduced in molecular weight. Of course, low molecular weight beta polyketone can also be used industrially effectively, and the present invention does not exclude this. Moreover, when reaction temperature exceeds 150 degreeC, nitrite ester etc. will be by-produced and may affect the yield of beta polyketone. In this case as well, the purity of the beta polyketone can be improved by appropriately providing a purification step.

  On the other hand, the lower limit of the temperature of the oxidation reaction is not particularly limited, but is preferably −50 ° C. or higher, more preferably −20 ° C. or higher, and most preferably 0 from the viewpoint of improving reaction efficiency and the like. It is above ℃.

The pressure of the oxidation reaction is not particularly limited, but in the case of using NO ₂ and N ₂ O ₄ in combination, from the viewpoint of increasing the ratio of N ₂ O ₄ , it is preferably 2 MPa or more, more preferably, 4 MPa or more.

  On the other hand, the upper limit of the pressure of the oxidation reaction is not particularly limited, but is preferably 30 MPa or less, more preferably 10 MPa or less.

  The reaction time of the oxidation reaction is not particularly limited, but is preferably in the range of 0.1 to 100 hours, and more preferably in the range of 0.5 to 5 hours.

In the present invention, when NO ₂ and / or N ₂ O ₄ is used as the oxidizing agent, carbon dioxide is preferably used as the solvent. If carbon dioxide is used as a solvent, the oxidation of the solvent can be prevented, wasteful consumption of NO ₂ and / or N ₂ O ₄ as oxidants, rapid combustion of the solvent, etc. can be avoided, and the safety of the reaction Can be turned. Further, as described above, the equilibrium between NO ₂ and N ₂ O ₄ can be adjusted by pressure. However, if carbon dioxide is used, the pressure can be easily adjusted, and the reactivity can be easily controlled.

In one embodiment of the present invention, in addition to the reaction temperature and pressure described above, the mixing ratio of carbon dioxide and NO ₂ and / or N ₂ O ₄ is such that the hydroxyl group of PVA is efficiently converted into a carbonyl group, and the enol type It can set suitably so that many products of the structure may be obtained.

The mixing ratio of the weight of carbon dioxide to the total weight of NO ₂ and N ₂ O ₄ can be appropriately selected according to the reaction temperature, reaction time, etc., but is preferably 1 to 5000 times, for example, 10 to 1000 It is more preferable that it is double, and it is most preferable that it is 50 to 500 times.

  In the present invention, carbon dioxide can be used in a gaseous state, but is preferably used in a liquid state or a supercritical state. Thereby, since the permeability and diffusibility of the raw material and the oxidizing agent can be improved, the oxidation reaction of the raw material can be progressed uniformly.

  Below, based on an example of the manufacturing method of beta polyketone, this invention is demonstrated in more detail.

  First, PVA is prepared as a raw material, and this is dissolved in a solvent such as water to prepare a solution. Even if the solvent is water, PVA can be easily dissolved by using, for example, warm water.

  Next, the prepared solution is applied onto a substrate and dried (casting) to obtain a PVA film.

  When oxidizing this PVA film, an autoclave (pressure vessel) can be suitably used as a reaction vessel.

First, the inside of the autoclave containing the PVA film is replaced with carbon dioxide, and then carbon dioxide containing NO ₂ is poured into the autoclave and enclosed in the autoclave.

  Next, the temperature in the autoclave is maintained at a predetermined temperature and pressure by a constant temperature bath, and a reaction is performed for a predetermined time.

  After the reaction, the inside of the autoclave is cooled, then the internal gas is released, and the pressure is recovered to normal pressure.

  The recovered film (beta polyketone film) can be purified by easily removing residual impurities by drying using a desiccator (dryer) or the like.

  In another embodiment of the purification, the separation of the beta polyketone and the impurities can also be realized by a difference in solvent solubility. As will be described later, since beta polyketone does not substantially dissolve in various solvents, it is possible to dissolve and separate only impurities by immersing beta polyketone in the solvent.

  The beta polyketone of the present invention can be preferably obtained by the above-described method for producing the beta polyketone of the present invention.

  The beta polyketone of the present invention has a structure represented by the following (2) (multiple repeating structure of oxoethylene units) (keto type), or a part of the carbonyl group (keto) is changed to enol. The enol-type tautomer is preferable.

  In the above (2), n is not particularly limited as long as it is 2 or more, but it is preferably 3 or more, and more preferably 4 or more. In particular, from the viewpoint of use as a functional polymer (polymer), n is preferably 10 or more, more preferably 50 or more, and most preferably 100 or more. Thereby, the property as a solid can be increased and handling property and stability of function expression can be improved.

  In the present invention, it is preferable that the beta polyketone has a molecular weight enough to become a solid. For example, the weight average molecular weight Mw is preferably in the range of 5,000 to 200,000.

  In the beta polyketone, both ends of the structure in which a plurality of oxoethylene units are repeated may each be a hydrogen atom or may be substituted with an arbitrary substituent.

  In the present invention, the function expression of the beta polyketone can be realized regardless of whether the terminal has a substituent. To give an extreme example, for example, even when the terminal of beta polyketone is used in a state of being fixed to the substrate surface directly or via an arbitrary linking group (for example, a monomolecular film), its function is expressed. Can do.

  The beta polyketone of the present invention can produce keto-enol tautomerism as represented by (4) below.

  In the above (4), the upper stage is a keto type beta polyketone, and the middle stage and the lower stage are enol type beta polyketones. These are in a tautomeric relationship with each other.

For this reason, the beta polyketone of the present invention exhibits keto type and / or enol type IR absorption. Specifically, keto-type IR absorption appears at 1710-1725 cm ⁻¹ , and enol-type IR absorption appears at 1620-1655 cm ⁻¹ . That is, an absorption peak can be shown in these ranges.

  Further, beta polyketone exhibits a maximum absorption at 209 nm in the UV spectrum, and an absorption based on conjugation due to enolization in the vicinity of 280 nm.

  In the enol-type beta polyketone, a hydrogen atom of a hydroxyl group can form a hydrogen bond with an oxygen atom of an adjacent carbonyl group (formation of a 6-membered ring structure including a hydrogen bond).

  If necessary, the beta polyketone is mutated to an enol type by the action of an acid catalyst, and is mutated to a keto type by the action of a base catalyst. This is a property common to general keto-enol tautomerism. It is also preferable to appropriately adjust the ratio of the tautomers of beta polyketone according to the use.

  In the present invention, it is preferable that the beta polyketone has a plurality of oxoethylene units represented by the following (1) regardless of keto type or enol type. These plural oxoethylene units are preferably contained in the main chain. The greater the number of oxoethylene units, the better, and it is preferably 2 or more, 3 or more, and 4 or more. More preferably, the oxoethylene unit is 10 or more, 100 or more, 1000 or more. In the present invention, there is no particular upper limit to the number of oxoethylene units.

  The above-mentioned polyketone (polyetheretherketone (PEEK)) has two benzene rings between ketone groups (carbonyl groups), and these ketone groups have a small interaction between the ketone groups. Further, the above alternating copolymer of olefin and carbon monoxide (polyketone having 1-oxotrimethylene as a repeating unit) also has two carbons between the ketone groups (γ polyketone or 1,4-polyketone). Therefore, those ketone groups have a small interaction between the ketone groups.

  In contrast, the beta polyketone of the present invention has a large interaction between ketone groups as described above. In particular, the longer the main chain is, the more distinctive properties due to its structure are. From such a viewpoint, it is preferable that the beta polyketone of the present invention has a molecular weight that is large enough to become, for example, a solid.

  The beta polyketone of the present invention can be suitably used as a functional material due to the unique characteristics derived from the structure as described above.

  In particular, when the molecular weight is increased, the property as a solid is increased, so that the handleability as a functional material is improved. In addition, it has been confirmed by the present inventor that beta polyketone is difficult to dissolve in various solvents such as water, THF, DMF, DMSO, toluene, NMP, and DMA, and this can also contribute to improvement in handleability. .

  Although it does not specifically limit as a functional material, For example, a metal ion extractant, an ion conductive polymer (for example, ion conductive film), an electrically conductive polymer (for example, transparent electrode) etc. can be illustrated preferably.

  Furthermore, examples of the functional material preferably include metal complex catalysts, paints, adhesives, affinity agents such as inks, and dispersants.

  Furthermore, the beta polyketone of the present invention can be subjected to a further reaction to induce further new functional materials.

  Since the beta polyketone of the present invention has an extraction ability to extract metal ions, it can be suitably used as a metal ion extractant. In particular, it can exhibit a specific metal ion extracting ability to selectively extract palladium, which is also classified as a rare metal.

  Hereinafter, metal ion extraction will be described in detail.

  In the method for producing the specific metal ion extractant of the present invention, the specific metal ion extractant is obtained by oxidizing polyvinyl alcohol as a raw material.

  A raw material is not limited to polyvinyl alcohol, You may use the raw material demonstrated with the manufacturing method of the beta polyketone mentioned above.

  Moreover, the structure demonstrated in the manufacturing method of the beta polyketone mentioned above can be used also about the oxidation of polyvinyl alcohol.

  In the method for producing a specific metal ion extractant of the present invention, it is not always necessary to strictly confirm that the specific metal ion extractant is a beta polyketone. This is because the specific metal ion extractant obtained can be suitably used as the specific metal ion extractant if it exhibits IR absorption derived from the keto type and / or enol type.

  It is also preferable in the present invention to oxidize the raw material so as to exhibit such IR absorption (that is, to use the change in IR absorption as an index for setting the oxidation reaction conditions). This is the same not only in the method for producing the specific metal ion extractant but also in the method for producing the beta polyketone described above.

  The specific metal ion extractant of the present invention is obtained by the method for producing a specific metal ion extractant described above, but is not necessarily limited to that obtained by this method.

  What contains the beta polyketone of this invention mentioned above as the specific metal ion extractant of this invention can be used suitably.

  Beta polyketone has a specific extraction ability of a specific metal ion extractant as its molecular weight increases. Specifically, it has been confirmed that the selectivity to palladium is increased. For example, substantially only palladium can be extracted with high selectivity from an aqueous solution containing palladium, platinum, and indium.

  In the metal ion extraction method of the present invention, metal ions are extracted using the specific metal ion extractant described above. The metal ions to be extracted are preferably palladium ions.

  In the metal ion extraction method of the present invention, when the specific metal ion extractant is used in a solid state, the above-described specific extraction ability is exhibited only by immersing it in a liquid containing metal ions. Moreover, metal ions can be recovered simply by pulling up from the liquid.

  Since the specific metal ion extractant of the present invention can reduce the solubility in an organic solvent or water, it can be used stably and can be easily recovered.

  Further, the specific metal ion extractant of the present invention is not limited to use in a liquid, and can exhibit an extraction ability in a gas phase or a solid phase.

  Most conventional specific metal ion extractants are small molecules and are used in a state dissolved in an organic solvent (chloroform, dichloromethane, toluene, ethylhexyl alcohol, etc.). Therefore, a flocculant and a filtration membrane may be required for recovery from the liquid. The use of organic solvents (especially dichloromethane) should be avoided as much as possible in consideration of the environment.

  On the other hand, the specific metal ion extractant of the present invention can exhibit an excellent effect even in a solid state, and can realize clean metal extraction not only in an organic solvent but also in water.

  Furthermore, since the beta polyketone of the present invention is basically composed of carbon, hydrogen and oxygen, the complete incineration disposal can be suitably applied. For example, as one aspect for recovering the metal, the remaining metal can be recovered by incinerating the beta polyketone on which the metal is adsorbed.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

  In the following examples, JASCO FT / IR-4100 ATR method (prism: Diamond) was used for IR measurement. For UV measurement, Hitachi Double Beam Spectrophotometer Model U-2000A was used. Shimadzu ICPS-7500 was used for ICP emission spectroscopic analysis.

1. Production of beta polyketone (Example 1)
PVA (Aldrich: Mowiol® 10-98, Mw˜61000, saponification degree 98.0-98.8 mol%, 0.2 g) was dissolved in distilled water (5 g) and cast to a thickness of about 30 μm. to form a film, which attached to the film holder in the cut 50mL stainless autoclave 20 × 30mm (20.6mg), and the CO ₂ 2 times substituted after CO ₂ was introduced 20g. The autoclave was cooled to 5 ° C. or lower in an ice bath. Those of NO ₂ was 0.54g accurately weighed into a stainless steel NO ₂ collection tube 3mL capacity with a valve at each end, mounted in series to the CO ₂ introduction line of 50mL stainless autoclave for reaction containing the sample, NO ₂ CO ₂ was poured from the top of the sampling tube. At this time, the total amount of CO ₂ was 50.7 g. Thereafter, the reaction autoclave was placed in a constant temperature layer, and the reaction temperature was 5 to 6 MPa at a container internal temperature of 18 ° C. and stirred for 1 hour. After the reaction, the mixture was cooled to 5 ° C. or lower in an ice bath, gas was released, the sample was taken out at normal pressure, and stored in a desiccator overnight. In the FT-IR-ATR measurement of the obtained film, the absorption derived from the keto type and the enol type at 1715 cm ⁻¹ and 1652 cm ⁻¹ was 0.23 times and 4.07 times the absorption intensity near 2930 cm ⁻¹ , respectively. A spectrum with double absorption intensity was obtained (FIG. 1).

(Example 2)
In Example 1, the PVA film was oxidized in the same manner as in Example 1 except that the amount of NO ₂ used was 0.53 g and the total amount of CO ₂ was 55.9 g. In the FT-IR-ATR measurement of the obtained film, the absorption derived from the keto type and the enol type at 1715 cm ⁻¹ and 1646 cm ⁻¹ was 1.59 times and 1.41 respectively with respect to the absorption intensity near 2930 cm ^−1. A spectrum with double absorption intensity was obtained.

Example 3
In Example 1, the PVA film was oxidized in the same manner as in Example 1 except that the amount of NO ₂ used was 0.45 g and the total amount of CO ₂ was 58.8 g. In the FT-IR-ATR measurement of the obtained film, the absorption derived from the keto type and the enol type at 1714 cm ⁻¹ and 1651 cm ⁻¹ was 0.76 times and 2.29 times the absorption intensity near 2930 cm ⁻¹ , respectively. A spectrum with double absorption intensity was obtained.

Example 4
PVA (Aldrich: Mowiol® 10-98, Mw˜61000, saponification degree 98.0-98.8 mol%, 0.2 g) was dissolved in distilled water (5 g) and cast to a thickness of about 30 μm. to form a film, which attached to the film holder of 90mg tori 50mL stainless autoclave, the the CO ₂ 2 times substituted after CO ₂ was introduced 20g. The autoclave was cooled to 5 ° C. or lower in an ice bath. Those of NO ₂ was 0.108g accurately weighed into a stainless steel NO ₂ collection tube 3mL capacity with a valve at each end, mounted in series to the CO ₂ introduction line of 50mL stainless autoclave for reaction containing the sample, NO ₂ CO ₂ was poured from the top of the sampling tube. At this time, the total amount of CO ₂ was 38.27 g. Thereafter, the reaction autoclave was placed in a constant temperature layer, and the reaction temperature was 4.8 to 5.3 MPa at a container internal temperature of 18 ° C., followed by stirring reaction for 1 hour. After the reaction, the mixture was cooled to 5 ° C. or lower in an ice bath, gas was released, the sample was taken out at normal pressure, and stored in a desiccator overnight. In the FT-IR-ATR measurement of the obtained film, the absorption derived from the keto type and the enol type at 1.717 cm ⁻¹ and 1651 cm ⁻¹ was 1.16 times and 2.16 times the absorption intensity near 2930 cm ⁻¹ , respectively. A spectrum with double absorption intensity was obtained. In the UV spectrum, the film before the treatment had no absorption in the wavelength range of 200 to 400 nm, whereas the film obtained by the oxidation treatment showed a maximum absorption at 209 nm and an absorption near 280 nm (FIG. 2).

(Example 5)
PVA (Kanto Chemical Co., Inc .: polymerization degree 500, saponification degree 86.5-89.0 mol%, 0.2 g) was dissolved in distilled water (5 g) and cast to prepare a film having a thickness of about 30 μm. attached to × 30 mm film holder of the cut 50mL stainless autoclave in (22.6 mg), the the CO ₂ 2 times substituted after CO ₂ was introduced 20g. The autoclave was cooled to 5 ° C. or lower in an ice bath. Those of NO ₂ was 0.60g accurately weighed into a stainless steel NO ₂ collection tube 3mL capacity with a valve at each end, mounted in series to the CO ₂ introduction line of 50mL stainless autoclave for reaction containing the sample, NO ₂ CO ₂ was poured from the top of the sampling tube. At this time, the total amount of CO ₂ was 59.0 g. Thereafter, the reaction autoclave was placed in a constant temperature layer, and the reaction temperature was 5 to 6 MPa at a container internal temperature of 18 ° C. and stirred for 1 hour. After the reaction, the mixture was cooled to 5 ° C. or lower in an ice bath, gas was released, the sample was taken out at normal pressure, and stored in a desiccator overnight. In the FT-IR-ATR measurement of the obtained film, the absorption derived from the keto type and the enol type at 1714 cm ⁻¹ and 1632 cm ⁻¹ was 1.07 times and 1.29 times the absorption intensity near 2930 cm ⁻¹ , respectively. A spectrum with double absorption intensity was obtained.

<Evaluation>
In Examples 1-5, the production | generation of the beta polyketone by the oxidation of PVA was confirmed from the measured optical characteristic.

2. Metal ion adsorption (extraction) experiment (Example 6)
Using the film obtained in Example 2, a metal ion adsorption experiment was performed.

  The film was immersed in 10 mL of a 0.1 M nitric acid acidic solution containing 1 mg / L of Pd (II) ions at 20 ° C. for 10 minutes, and the Pd (II) ion concentration before and after the treatment was analyzed with an ICP emission spectrometer. Later, 100% of Pd (II) was extracted.

(Example 7)
The metal ion adsorption experiment using the film obtained in Example 3 was performed.

  The film was dipped in 10 mL of 0.1 M nitric acid acidic solution containing 10 mg / L of Pd (II) ions at 20 ° C. for 10 minutes, and the Pd (II) ion concentration before and after the treatment was analyzed with an ICP emission spectrometer. Later 87% of Pd (II) was extracted.

(Example 8)
In Example 7, the same test as in Example 7 was conducted except that a solution containing platinum or indium instead of palladium was used as the metal ion, and neither platinum nor indium was extracted.

<Evaluation>
From Examples 6 and 7, it can be seen that the beta polyketone has an excellent extraction ability for palladium.

  Furthermore, it can be seen from the comparison between Examples 6 and 7 and Example 8 that the beta polyketone can exhibit an extraction ability selective to palladium.

3. Solubility test

Example 9
2 mg of beta polyketone powder obtained by pulverizing the film obtained in Example 4 was added to various solvents shown in Table 1 below, and stirred at the temperatures shown in Table 1 for 0.5 hours.

  As a result, it was confirmed that beta polyketone did not dissolve in any solvent under the conditions shown in Table 1.

<Evaluation>
From the results of Example 9, it can be seen that beta polyketone is hardly soluble in various solvents. This shows that the function of beta polyketone is easily exhibited stably in various solvents.

Claims (16)

  A method for producing beta polyketone, characterized in that beta polyketone is obtained by oxidizing polyvinyl alcohol.   The method for producing a beta polyketone according to claim 1, wherein the polyvinyl alcohol is oxidized using an oxidizing agent.   The method for producing beta polyketone according to claim 2, wherein nitrogen oxide is used as the oxidizing agent.   The method for producing a beta polyketone according to claim 3, wherein nitrogen dioxide and / or dinitrogen tetroxide is used as the nitrogen oxide.   A beta polyketone obtained by the method for producing a beta polyketone according to claim 1.   The beta polyketone according to claim 5, which exhibits IR absorption derived from keto type and / or enol type. The beta polyketone according to claim 6, wherein the IR absorption appears at 1710 to 1725 cm ⁻¹ and / or 1620 to 1655 cm ⁻¹ . The beta polyketone according to any one of claims 5 to 7, comprising a plurality of oxoethylene units represented by the following (1).

  A method for producing a specific metal ion extractant, comprising obtaining a specific metal ion extractant by oxidizing polyvinyl alcohol.   The method for producing a specific metal ion extractant according to claim 9, wherein the polyvinyl alcohol is oxidized using an oxidizing agent.   The method for producing a specific metal ion extractant according to claim 10, wherein nitrogen oxide is used as the oxidant.   The method for producing a specific metal ion extractant according to claim 11, wherein nitrogen dioxide and / or dinitrogen tetroxide is used as the nitrogen oxide.   A specific metal ion extractant obtained by the method for producing a specific metal ion extractant according to claim 9.   The specific metal ion extractant according to claim 13, which exhibits IR absorption derived from keto type and / or enol type. The specific metal ion extractant according to claim 14, wherein the IR absorption appears at 1710 to 1725 cm ^-1 and / or 1620 to 1655 cm ^-1 .   The specific metal ion extractant according to any one of claims 13 to 15, which has an extraction ability for palladium ions.

Images