Polymer macromolecule, and gel dispersion liquid and gel mass each using same

Abstract

The purpose of the present invention is to provide: a polymer macromolecule in which the particle diameter of gel particles that are formed when the polymer macromolecule is formed into a hydrogel is fine; and a gel dispersion liquid and a gel mass each using the polymer macromolecule. The polymer macromolecule is a homopolymer that is composed of a monomer unit (A) having a zwitterionic group, or a copolymer that is composed of the monomer unit (A) and another monomer unit (B). The polymer macromolecule has a weight average molecular weight of 400,000 or less as determined by gel permeation chromatography using a mixed solvent of water and methanol as an eluent and using polyethylene glycol as a standard sample. It is preferable that the other monomer unit (B) contains an N-succinimide ester group. The gel dispersion liquid and the gel mass are obtained by adding water to the polymer macromolecule.

Description

Polymer polymers, and gel dispersions and gel aggregates using the same

[0001] This invention relates to polymer polymers, as well as gel dispersions and gel aggregates using the same.

[0002] In recent years, there has been active development of biofuel cells that use biocatalysts such as enzymes and microorganisms to convert biomass such as glucose into electrical energy. In biofuel cells, the electrode reaction involves the oxidation of fuel such as glucose by the biocatalyst, and the transfer of electrons to the electrodes. This electron transfer from the biocatalyst to the electrodes is generally mediated by redox compounds called mediators. In addition to glucose, ethanol and sugars such as lactose are also being considered as fuels for biofuel cells. Furthermore, the use of microorganisms as biocatalysts is also being researched.

[0003] As a safe power source for living organisms, biofuel cells are expected to be used in portable devices that come into contact with the human body and in implantable medical devices. However, conventional biofuel cells have problems such as low power density (especially current density) and the durability of the biocatalysts. Power density depends on the type of enzyme and mediator, as well as the method of immobilizing them on the electrodes and the non-surface area of ​​the electrode material.

[0004] Electrodes in which monolayers of mediators and enzymes are formed on a gold substrate, and electrodes in which enzymes and mediators are immobilized using polymers, have been studied (for example, Non-Patent Document 1). However, with polymers used to immobilize enzymes and mediators, the amount of immobilized material is small, and as a result, it has been difficult to obtain a sufficient power density.

[0005] In contrast, a hydrogel has been disclosed that is formed from a copolymer containing monomer units i) having zwitterionic groups in the side chains and monomer units ii) having N-succinimide ester groups in the side chains as repeating units (see Patent Document 1). This hydrogel allows for the effective and stable immobilization of proteins such as enzymes and mediator compounds used in electrodes of biofuel cells.

[0006] This has given momentum to the practical application of biofuel cells, but there is a desire for improved usability and further performance enhancements, as well as various requirements regarding the properties of the hydrogel. Furthermore, the use of this hydrogel for purposes other than electrodes in biofuel cells is being considered, but there are also various requirements regarding the properties of each application.

[0007] The hydrogel described in Patent Document 1 has a polymer (copolymer polymer) that forms relatively large particles through pseudo-physical crosslinking with water molecules via hydrogen bonding. If the gel particles of this hydrogel can be made finer, for example, foreign matter can be quickly removed by mesh filtration after polymer polymerization, thereby reducing filtration costs in the polymerization process. Furthermore, if the size of these gel particles is sufficiently small, the hydrogel becomes transparent or translucent, which is extremely useful in practical applications, for example, when the hydrogel is used to immobilize enzymes in electrodes of a biofuel cell, as the enzyme reaction can be optically analyzed in real time. In Patent Document 1, the generated polymer is obtained as a solid precipitate and is removed from the reaction solution system, making it difficult to obtain the product with good reproducibility. Also, the fact that it is obtained as a precipitate in the reaction vessel leaves room for improvement in terms of handling the product when mass-producing it industrially.

[0008] Japanese Patent Publication No. 2019-199603

[0009] Heller et al., Phys. Chem. Chem. Phys., 6, 209-216, 2004

[0010] Therefore, the present invention aims to provide a polymer polymer that, when used as a hydrogel, produces gel particles with a fine particle size, as well as a gel dispersion and a gel mass using the same.

[0011] The above objectives are achieved by the following inventions <1> to <9>. <1> A polymer polymer which is a homopolymer consisting of a monomer unit (A) having a zwitterionic group, or a copolymer consisting of the monomer unit (A) and other monomer units (B), wherein the weight-average molecular weight obtained by gel permeation chromatography using a mixed solvent of water and methanol as the eluent and polyethylene glycol as the standard sample is 400,000 or less, and the other monomer unit (B) is a monomer unit (B') containing an N-succinimide ester group.

[0012] <2> A polymer polymer that is a homopolymer consisting of a monomer unit (A) having a zwitterionic group, or a copolymer consisting of the monomer unit (A) and other monomer units (B), wherein the weight-average molecular weight obtained by gel permeation chromatography using a mixed solvent of water and methanol as the eluent and polyethylene glycol as the standard sample is 400,000 or less, and in a dispersion of 1 mL of water added to 10 mg of the polymer polymer, gel particles are formed, and in the dynamic light scattering of the gel particles, the volume fraction of the peak with an average particle size of 1,000 nm or less is 30% or more, and the maximum diameter of the gel particles is 10,000 nm or less.

[0013] <3> The polymer polymer according to <2>, wherein the volume fraction of the peak with an average particle size of 1000 nm or less in the dynamic light scattering of the gel particles is 95% or more.

[0014] <4> The polymer polymer according to <2>, wherein the other monomer unit (B) is a monomer unit (B') containing an N-succinimide ester group. <5> The polymer polymer according to <1> or <2>, wherein the molar ratio of the monomer unit (A) to the monomer unit (B) [(A):(B)] is in the range of 100:0 to 20:80.

[0015] <6> The polymer polymer according to <1> or <2>, wherein when at least one amount of water in the range of 0.5 mL to 2.0 mL is added to 1 g of the polymer polymer, it does not exhibit fluidity and forms a transparent or translucent gel mass.

[0016] <7> The polymer polymer according to <1> or <2>, wherein the zwitterionic group is any functional group selected from the group consisting of a phosphobetaine group, a sulfobetaine group, and a carboxybetaine group.

[0017] <8> The monomer unit (A) is of the following formula (I) (wherein R １ R represents a linear or branched alkyl group having 1 to 5 carbon atoms. ２ R represents a linear or branched alkylene group having 1 to 20 carbon atoms. ５ R represents a directly bonded or linear or branched alkylene group having 1 to 20 carbon atoms. The monomer unit (B) has the structure of the following formula (II) (wherein R ３ R represents a linear or branched alkyl group having 1 to 5 carbon atoms. ４ The polymer polymer described in <1> or <2> has the structure of (where represents a directly bonded or linear or branched alkylene group having 1 to 5 carbon atoms).

[0018]

[0019]

[0020] <9> A gel dispersion obtained by adding water to the polymer polymer described in <1> or <2>.

[0021] <10> A transparent or translucent gel mass obtained by adding water to the polymer polymer described in <1> or <2>.

[0022] According to the present invention, it is possible to provide a polymer polymer that, when used as a hydrogel, produces gel particles with a fine particle size, as well as a gel dispersion and a gel mass using the same.

[0023] These are photographs of the solid gel formed by the polymer polymer of Example 1. (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Example 2. (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Example 5. (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Example 9. (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Example 14, where (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Example 12, where (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Comparative Example 1, where (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency. These are photographs of the solid gel formed by the polymer polymer of Comparative Example 3, where (a) is a photograph of the solid gel immediately after formation, (b) is a photograph of the solid gel after the flowability test, and (c) is a photograph for evaluating transparency.

[0024] Embodiments of the present invention will be described below. However, the present invention is not limited to the configurations of the embodiments described below, and can be implemented with appropriate modifications without sacrificing the spirit of the invention.

[0025] [Polymer Polymer] (Structure of Polymer Polymer) The polymer polymer according to this embodiment is a homopolymer consisting of monomer units (A) having zwitterionic groups, or a copolymer consisting of the monomer units (A) and other monomer units (B). In the case of the latter copolymer, the monomer units (A) and monomer units (B) are typically bonded randomly, but embodiments having some kind of regularity or periodicity are also included in the scope of this embodiment. For example, it can be an alternating polymer, a periodic polymer, a block copolymer, and in some cases, a graft polymer. The polymer polymer according to this embodiment, including the former homopolymer, may also include monomer units other than monomer units (A) and monomer units (B) depending on the circumstances.

[0026] The zwitterionic group contained in the monomer unit (A) in the copolymer has a structure in which both positive and negative charges are present within the substituent, and is also called an amphoteric ion group. The presence of a zwitterionic group in the monomer unit (A) imparts hydrophilicity to the polymer, making it possible to maintain biological functions such as enzymes even after immobilization. Such zwitterions may be present in the side chains of the copolymer, or in other positions, such as at the ends.

[0027] Preferably, such zwitterions are the side chain portions in the polymer structures shown in (a) to (c) below, namely (a) a phosphorylcholine group (phosphobetaine group), (b) a sulfobetaine group, and (c) a carboxybetaine group. The phosphorylcholine group (PC group) is a polar group that has a structure similar to the polar group of phospholipids (phosphatidylcholine), which are the main components of biological membranes.

[0028]

[0029] The monomer unit (B) in the copolymer is a monomer unit (B') containing an N-succinimide ester group in one aspect (Embodiment 1) of the present embodiment. On the other hand, in another aspect (Embodiment 2) of the present embodiment, the monomer unit (B) is not limited to the monomer unit (B') containing an N-succinimide ester group.

[0030] In Embodiment 2, examples of the monomer unit (B) include monomer units (B') containing an N-succinimide ester group, alkyl methacrylates having 1 to 12 carbon atoms in the alkyl group, alkyl acrylates having 1 to 12 carbon atoms in the alkyl group, styrene, vinyl acetate, and the like.

[0031] In Embodiment 2, examples of the alkyl methacrylate having 1 to 12 carbon atoms in the alkyl group that can be included in the monomer unit (B) include methyl methacrylate and butyl methacrylate. The type of the monomer unit (B) may be one kind or two or more kinds. The monomer unit (B) may be, for example, one kind or a combination of two or more kinds selected from the group consisting of a monomer unit containing an N-succinimide ester group, an alkyl methacrylate having 1 to 12 carbon atoms in the alkyl group, an alkyl acrylate having 1 to 12 carbon atoms in the alkyl group, styrene, and vinyl acetate.

[0032] When the monomer unit (B) is only one kind, it is preferably a monomer unit containing an N-succinimide ester group. When the monomer unit (B) is a combination of two or more kinds, it is preferably a combination of a monomer unit containing an N-succinimide ester group and other monomer units.

[0033] When the monomer unit (B) contains an N-succinimide ester group, regardless of Embodiment 1 and Embodiment 2, the N-succinimide ester group is a highly reactive active ester, which reacts with an amino group in a protein such as an enzyme to form a covalent bond (amide bond), thereby immobilizing the enzyme or the like in the hydrogel. In addition, in addition to enzymes and the like, a mediator compound having an amino group can also be similarly immobilized by forming a covalent bond.

[0034] The polymerization sites in the monomer units that form the main chain (skeleton) structure in the above polymer are not particularly limited as long as they can polymerize with each other to form a polymer. Specifically, for example, vinyl monomer residues, acetylene monomer residues, ester monomer residues, amide monomer residues, ether monomer residues, urethane monomer residues, etc. are preferred, and among these, vinyl monomer residues are more preferred. The vinyl monomer residue is not particularly limited, but for example, a methacryloxy group, a methacrylamide group, an acryl oxy group, an acrylamide group, a styryloxy group, a styrylamide group, etc. in a state where the vinyl portion is undergoing addition polymerization can be used, and among these, a methacryloxy group is preferred. And the above polymerization sites can be the same for each monomer unit or can be different independently, but in any case, a vinyl monomer residue, particularly a methacryloxy group, is a preferred embodiment. Therefore, in a preferred embodiment, the main chain structure of the copolymer has a structure in which vinyl groups are polymerized, and more preferably, has an acrylic polymer structure.

[0035] The monomer unit (A) preferably has a structure represented by the following formula (I).

[0036]

[0037] In the above formula (I), R １ represents a linear or branched alkyl group having 1 to 5 carbon atoms, preferably a linear alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group. In the above formula (I), R ２represents a linear or branched alkylene group having 1 to 5 carbon atoms, preferably a linear alkylene group having 1 to 5 carbon atoms, and more preferably a methylene group. In the above formula (I), R ５ represents a direct bond or a linear or branched alkylene group having 1 to 20 carbon atoms, and more preferably a direct bond.

[0038] Specific examples of the monomer unit (A) include, but are not limited to, for example, structural units derived from 2-methacryloyloxyethyl phosphorylcholine, 2-acryloyloxyethyl phosphorylcholine, N-(2-methacrylamide)ethyl phosphorylcholine, 4-methacryloyloxybutyl phosphorylcholine, 6-methacryloyloxyhexyl phosphorylcholine, 10-methacryloyloxydecylsyl phosphorylcholine, ω-methacryloyldioxyethylene phosphorylcholine, and 4-styryloxybutyl phosphorylcholine. Among these, a structural unit derived from 2-methacryloyloxyethyl phosphorylcholine is particularly preferred. These are examples having a phosphorylcholine group as an amphoteric ion group, but monomer units in which the portion corresponding to the phosphorylcholine group is replaced with a sulfobetaine group or a carboxybetaine group can also be used as described above.

[0039] Further, as the monomer unit (B), it preferably has a structure represented by the following formula (II), which is an example of the monomer unit (B') containing an N-succinimide ester group.

[0040]

[0041] In the above formula (II), R ３ represents a linear or branched alkyl group having 1 to 5 carbon atoms, preferably a linear alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group. In the above formula (II), R ４ represents a direct bond or a linear or branched alkylene group having 1 to 5 carbon atoms, preferably a direct bond or a linear alkylene group having 1 to 5 carbon atoms, and more preferably a direct bond.

[0042] In the polymer polymer according to this embodiment, the molar ratio of monomer unit (A) to monomer unit (B) [(A):(B)] (hereinafter sometimes simply referred to as [(A):(B)]) is preferably in the range of 100:0 to 20:80. For monomer unit (A), it is more preferable that [(A):(B)] = 90:10 or less, and even more preferable that [(A):(B)] = 80:20 or less. Furthermore, for monomer unit (B), it is more preferable that [(A):(B)] = 30:70 or less, and even more preferable that [(A):(B)] = 40:60 or less.

[0043] In [(A):(B)], if there is a large amount of monomer unit (A), i.e., a small proportion of monomer unit (B), the immobilization of electron carriers (electron transfer mediators) may be insufficient, for example, when used as electrodes in a biofuel cell, which is undesirable depending on the application. On the other hand, if there is a large amount of monomer unit (B), i.e., a small amount of monomer unit (A), the particle size of the gel particles produced when a hydrogel is formed tends to be large, or a hydrogel may not be formed at all, which is undesirable.

[0044] In a particularly preferred embodiment, in formulas (I) and (II) above, R １ is a methyl group, R ２ is a methylene group, R ３ is a methyl group, R ４ This is a direct bond. In this case, the homopolymer consisting of monomer unit (A), or the copolymer consisting of monomer unit (A) and monomer unit (B), has the following structure.

[0045]

[0046] Here, m and n are the number of monomer units in the polymer, and independently of each other, m represents an integer of 2 or more, and n represents an integer of 0 or more. The ratio of each monomer unit, m:n, is preferably 100:0 to 20:80, as described above. Also, as described above, a typical configuration is in which each monomer unit is bonded in a random order, but configurations having some kind of regularity or periodicity are also included in the scope of this embodiment, and can be, for example, alternating polymers, periodic polymers, block copolymers, or graft polymers.

[0047] As described above, the polymer polymer according to this embodiment may optionally include monomer units other than those exemplified as monomer unit (A) and monomer unit (B). By including, for example, a monomer unit having a hydrophobic group in its side chain as the other monomer unit, it may be possible to reduce the amount of water contained in the hydrogel and improve its strength, if necessary.

[0048] (Weight-average molecular weight Mw of polymer) The weight-average molecular weight Mw of the polymer according to this embodiment is measured by gel permeation chromatography (hereinafter sometimes abbreviated as "GPC") using a mixed solvent of water and methanol as the eluent and polyethylene glycol as the standard sample, and is 400,000 or less, preferably 150,000 or less, more preferably 50,000 or less, and even more preferably 30,000 or less. A smaller weight-average molecular weight Mw tends to result in finer particle sizes of gel particles when hydrogel is formed. If the weight-average molecular weight Mw is too large, the particle size of the gel particles formed when hydrogel is formed becomes too large, which is undesirable when transparency is required for the mass gel.

[0049] Furthermore, in the GPC measurement described later, if the substance does not dissolve in the GPC solvent (particularly a mixture of ion-exchanged water and methanol in a volume ratio of 7:3) and therefore cannot be measured, it is estimated that the weight-average molecular weight exceeds 400,000.

[0050] The lower limit of the weight-average molecular weight Mw of the polymer according to this embodiment is not particularly limited as long as it is a polymer, but it is preferably 1000 or more, and more preferably 2000 or more. If the weight-average molecular weight Mw is too small, there is a concern that a hydrogel may not form or that the strength of the aggregate gel may not be sufficient.

[0051] (Method for producing polymer polymers) The method for producing polymer polymers according to this embodiment is not particularly limited, provided that a polymer polymer with the desired weight-average molecular weight Mw and properties can be obtained. This can be done by conventional methods, including the preparation of monomer compounds and their polymerization, based on the level of skill of those skilled in the art. For polymer synthesis, known methods such as radical polymerization, living radical polymerization, cationic polymerization, anionic polymerization, or solution polymerization, emulsion polymerization, and suspension polymerization can be used. Among these, RAFT polymerization, a type of living radical polymerization, is preferred in this embodiment because it is simple and allows for easy control of the molecular weight distribution.

[0052] The following describes specific additives and conditions for radical polymerization, including living radical polymerization, but this is not intended to exclude other polymerization methods.

[0053] As polymerization initiators in radical polymerization and living radical polymerization, any substance that decomposes and generates radicals in the reaction temperature range of 30 to 90°C can be used without particular restrictions. Specific examples of such polymerization initiators include, for example, 2,2-azobis(2-amidinopropyl) dihydrochloride, 4,4-azobis(4-cyanovaleric acid), 2,2-azobis(2-(5-methyl-2-imidazolin-2-yl)propane) dihydrochloride, 2,2-azobisisobutylamide dihydrate, 2,2-azobisisobutyronitrile, ammonium persulfate, potassium persulfate, benzoyl peroxide, succinate peroxide, diisopropyl peroxydicarbonate, t-butylperoxy-2-ethylhexanoate, t-butylperoxypivalate, t-butylperoxydiisobutyrate, lauroyl peroxide, 2,2-azobis(2,4-dimethylvaleronitrile), t-butylperoxyneodecanoate, and the like. Preferably, it is 2,2-azobisisobutyronitrile.

[0054] These radical polymerization initiators may be used individually or in mixtures. Various redox accelerators may also be used as polymerization initiators. In conventional radical polymerization, the amount of polymerization initiator used is preferably less than 5 mM in the reaction solution, but this is not the case in RAFT polymerization. Dithiobenzoate, trithiocarbonate, and dithiocarbamate-based chain transfer agents (RAFT agents) can all be used in RAFT polymerization.

[0055] From the viewpoint of polymerization efficiency, the concentration of monomers in the polymerization reaction solution is preferably 0.05 M to 10 M, and more preferably 0.1 M to 5 M, in terms of the total concentration of all monomers. Any solvent capable of dissolving each monomer can be used in the polymerization reaction, but a mixed solvent of chloroform and ethanol is particularly preferred from the viewpoint of the solubility of the resulting polymer and the ease of solvent removal. The reaction temperature is usually in the range of 30 to 90°C, and particularly preferably 40 to 75°C.

[0056] (Characteristics of the Polymer) The polymer according to Embodiment 2 of this embodiment forms (hydro)gel particles in a dispersion of 1 mL of water added to 10 mg of the polymer, and in the dynamic light scattering of the gel particles, the volume fraction of the peak with an average particle size of 1000 nm or less is 30 volume% or more, and the maximum diameter of the gel particles is 10000 nm or less. Furthermore, it is preferable that the volume fraction of the peak with an average particle size of 1000 nm or less in the dynamic light scattering of the gel particles is 95 volume% or more. Moreover, it is more preferable that at least 95 volume% of the gel particles have a particle diameter of 100 nm or less, even more preferable that they have a particle diameter of 40 nm or less, and particularly preferable that they have a particle diameter of 20 nm or less.

[0057] It should be noted that the "1 mL of water per 10 mg of polymer" specified here is merely a concentration for preparing a sample to determine the properties of the polymer, and the concentration of polymer in the hydrogel dispersion that yields fine gel particles is not limited to this. The concentration of polymer in the hydrogel dispersion can be selected from a range of approximately 0.1 μg to 500 mg / mL, preferably from approximately 1 μg to 200 mg / mL, depending on the application, purpose, and desired properties.

[0058] In the case where the polymer according to this embodiment is a copolymer consisting of monomer unit (A) and monomer unit (B), the included zwitterionic groups exhibit biocompatibility, such as not adsorbing proteins. If monomer unit (B) contains an N-succinimide ester group, an electron transfer mediator can be immobilized using the N-succinimide ester group, making it possible to use it as a biofuel cell that uses biocatalysts such as enzymes or microorganisms and biomass such as glucose as fuel.

[0059] Furthermore, smaller gel particle sizes allow for rapid removal of foreign matter by mesh filtration after polymer polymerization, thereby reducing filtration costs in the polymerization process.

[0060] Furthermore, if the gel particles are large, there is a concern that they may precipitate depending on the solvent and the gel being protected, but if the gel particles are fine, such concerns are eliminated or at least mitigated.

[0061] Furthermore, when bioactive substances are protected with hydrogels and administered intravenously, there are concerns that large gel particles may easily clog blood vessels or become difficult to excrete from the body. However, if the gel particles are very fine, such concerns are eliminated or at least mitigated.

[0062] The polymer according to this embodiment can be obtained such that, when at least one amount of water in the range of 0.5 mL to 2.0 mL is added to 1 g of the polymer, it does not exhibit fluidity and forms a transparent or translucent gel mass.

[0063] The polymer polymer according to this embodiment produces fine gel particles when formed into a hydrogel. Therefore, even when the amount of water added is reduced to increase viscosity and suppress fluidity, a transparent or translucent gel mass can be formed. This is because, even if there is a refractive index difference between water and gel particles, the gel will be transparent or translucent if the diameter of the gel particles is sufficiently smaller than the wavelength of visible light (shortest 400 nm), and will become transparent if the gel particles are about one-tenth or less the wavelength of visible light.

[0064] Furthermore, in this embodiment, when the amount of water added is reduced and the viscosity is increased to suppress fluidity, the polymer can bond relatively strongly to water molecules in a cross-linked state due to the balance of hydrophilicity and hydrophobicity in the molecular structure, and can become a gel mass that does not exhibit fluidity within the above predetermined water amount range.

[0065] Such non-fluid, transparent or translucent gel masses have various applications, as described below.

[0066] Because it does not exhibit fluidity, it can take the form of a film or other material, making it suitable for use as an implantable device in applications such as biofuel cells. Furthermore, for example, when using hydrogel to immobilize enzymes in the electrodes of a biofuel cell, if the hydrogel used is opaque, real-time optical analysis is not possible. However, if the enzyme is immobilized as a transparent or translucent gel mass, it becomes optically visible and real-time analysis becomes possible, making it extremely useful in practical applications.

[0067] In this embodiment, "not exhibiting fluidity" of the gel mass means that after generating the gel mass in a container such as a reagent bottle or test tube and letting it stand for 24 hours or more, and then tilting it 45° and letting it stand for 5 minutes, there is no change (no movement) in the liquid surface.

[0068] In this embodiment, the "transparent" or "translucent" state of the gel mass is determined by the following evaluation criteria. Specifically, a polymer and water are mixed in a glass container with a flat bottom so that the height from the bottom surface is 2.5 ± 0.5 mm to produce a gel mass, which is then left to stand for 24 hours or more. After that, a sheet with characters of a predetermined size printed on it is placed under the bottom of the glass container, and the characters on the sheet are visually inspected from above through the gel mass. As a result, the state in which the characters are clearly visible is judged as "transparent," the state in which the characters can be recognized to some extent, albeit blurred, is judged as "translucent," and the state in which the characters cannot be recognized or nothing is visible is judged as "opaque."

[0069] The embodiments described above are merely examples of typical forms of the present invention, and the present invention is not limited to these embodiments. Those skilled in the art can carry out various modifications without departing from the core of the present invention, in accordance with conventionally known knowledge. As long as such modifications still possess the polymer polymer of the present invention, and the gel dispersion and gel mass using the same, they are of course included within the scope of the present invention.

[0070] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0071] (Preparation of test materials) The materials shown in Table 1 below were prepared.

[0072]

[0073] [Example 1] 0.551 g (3.01 mM) of monomer b, 0.881 g (2.98 mM) of monomer a, and 4.00 mL of a mixed solvent of chloroform and ethanol in a volume ratio of 6:4 were added to a glass reaction tube with an outer diameter of 21 mm and a length of 120 mm, and the mixture was stirred with a magnetic stirrer to dissolve. 1.00 mL of a solution of chain transfer agent c dissolved in the above mixed solvent at a concentration of 26.6 mg / mL was added, and the mixture was bubbled with nitrogen for 12 minutes.

[0074] Subsequently, 1.00 mL of a solution in which radical polymerization initiator d was dissolved in the above mixed solvent at a concentration of 5.0 mg / mL was added, the reaction tube was sealed, and the reaction was carried out by heating in an oil bath at 59°C for 24 hours while stirring. Next, the reaction mixture was added dropwise to 300 mL of stirred chloroform to precipitate, and filtered through filter paper. The solid remaining on the filter paper was placed in a plastic container, and the solvent was removed under reduced pressure with a vacuum pump for 24 hours or more until a constant weight was obtained. The product obtained as a roughly powdered substance was then ground into a fine powder using a mortar and pestle to obtain the polymer polymer of Example 1.

[0075] Regarding the polymer obtained in Example 1, (1) a dispersion of gel particles was prepared and dynamic light scattering was measured according to the following procedure. Similarly, (2) a solid gel was formed and its (2-1) fluidity and (2-2) transparency were observed. Furthermore, (3) the side chain of the monomer b portion of the polymer obtained in Example 1 was hydrolyzed according to the following procedure, and (3-1) １ ¹H-NMR spectroscopy and (3-2) GPC were used to measure the weight-average molecular weight Mw. The results are summarized in Tables 3 and 4 below.

[0076] (1) Preparation of gel particle dispersion and measurement of dynamic light scattering In a glass screw-top bottle with an outer diameter of 20 mm and a height of 45 mm, 1 mL of deionized water was added to 10 mg of the polymer polymer (unhydrolyzed) from Example 1, and the mixture was shaken to prepare a gel particle dispersion. The obtained dispersion was used as a sample for dynamic light scattering, and dynamic light scattering was measured in the range of 0 to 10000 nm using a Malvern Panalytical Zetasizer Pro ZSU3200, and the particle size distribution was displayed on a volume basis. The results are summarized in Table 3 below. Table 3 shows the average particle size and its abundance ratio for each peak, but only peaks with an abundance ratio of 0.1% or more are shown, and peaks with an abundance ratio of less than 0.1% were deemed to be practically negligible and were omitted.

[0077] (2) Formation of the lump gel In a glass screw-top bottle with an outer diameter of 20 mm and a height of 45 mm, 200 mg of the polymer polymer (not a hydrolyzate) from Example 1 was mixed with 200 mg of deionized water (ratio of water to polymer polymer (hereinafter referred to as "water / polymer ratio") = 1.00) and left to stand for 24 hours to form a lump gel. Figure 1(a) shows a photograph of the lump gel immediately after formation in Example 1, taken from diagonally above with the screw-top bottle placed on a horizontal stand. The following observations were made to the formed lump gel. The results are summarized in Table 4 below.

[0078] (2-1) Fluidity A fluidity test was performed by tilting the screw-cap bottle at a 45° angle and letting it stand for 5 minutes after it had been left to stand for 24 hours. Figure 1(b) shows a photograph of the lump gel in Example 1 after the fluidity test. The liquid surface was observed after the fluidity test. If there was no change in the liquid surface (it remained motionless at a 45° angle), it was considered that it did not exhibit fluidity, and if there was movement in the liquid surface, it was considered that it exhibited fluidity.

[0079] (2-2) Transparency The 2.5 mm ± 0.5 mm high gel mass inside the screw-cap bottle was visually observed after standing for 24 hours. Additionally, a sheet with 11-point alphabet letters (10 or more letters) printed on it was placed under the bottom of the screw-cap bottle, and the letters on the sheet were visually observed from above through the gel mass. Figure 1(c) shows a photograph taken from above of the gel mass in Example 1 to evaluate its transparency.

[0080] Based on visual inspection, a state where the characters are clearly visible without any blurring is classified as "transparent," a state where some or all of the characters are blurred but can still be read is classified as "semi-transparent 1," and a state where the characters are difficult to read but can still be recognized to some extent as characters is classified as "semi-transparent 2." On the other hand, if the characters cannot be recognized or nothing is visible based on visual inspection, it is classified as "opaque."

[0081] (3) Hydrolysis of polymer polymer 30 mg of the polymer polymer from Example 1 was added to 15 mL of deionized water, and while stirring, an equimolar amount α of the monomer unit (b) MNHS in the polymer polymer was added with a sodium hydroxide aqueous solution of known concentration, and stirring was continued for 4 days. During this time, 0.2 times the amount of sodium hydroxide compared to the above equimolar amount α was added three times.

[0082] In Example 1, specifically, 30 mg of polymer with a starting ratio of (a) MPC / (b) MNHS = 49.8 / 50.2 was weighed (since the molecular weight of the polymer per mole is 239.2, the molar amount of (b) MNHS α = 0.0629 mmol), and 15 ml of deionized water was added and stirred. Separately, 95.4 mg of granular sodium hydroxide was dissolved in 40 mL of deionized water to obtain an aqueous sodium hydroxide solution β. Since 95.4 mg of sodium hydroxide is 2.385 mmol, 1.06 mL of the aqueous sodium hydroxide solution β, which gives α = 0.0629 mmol, was added to the mixture of the polymer and deionized water, and stirring was continued for 4 days. During that time, 0.21 mL of the aqueous sodium hydroxide solution β, which is 0.2 times the above equimolar amount α, was added three times.

[0083] Subsequently, this aqueous solution was placed inside a cylindrical Fujifilm Wako Pure Chemical Industries dialysis membrane, size 27, with both ends clipped, and dialysis was performed by stirring in 1 liter of deionized water for 24 hours to remove sodium hydroxide and low molecular weight compounds. During this time, the 1 liter of deionized water was replaced four times.

[0084] The aqueous solution after dialysis was placed in a freeze-drying container, frozen by immersion in liquid nitrogen, and freeze-dried at room temperature under reduced pressure of 12.5 Pa to obtain the hydrolyzed polymer product of Example 1.

[0085] (3-1)１ 10 mg of the hydrolyzed polymer of the polymer in Example 1 was dissolved in 1.0 mL of heavy water for measurement of the H-NMR spectrum. １ H-NMR samples were used. Spectra were obtained using a JEOL ECS-400 spectrometer with 32 integrations. Delta was used as the data processing software. The ratio of monomer units in the copolymer polymer was determined from the integral ratio of the methyl groups of the methacrylic group and the methyl groups bonded to the nitrogen of the phosphorylcholine group.

[0086] (3-2) Measurement of GPC In this embodiment and the examples described later, the weight-average molecular weight Mw was measured using a combination of a PU-2080 pump manufactured by JASCO Corporation and an RI-2031 RI detector, with one Shodex SB-804 HQ column. A mixture of ion-exchanged water and methanol in a volume ratio of 7:3 was prepared as an eluent by adding an amount of lithium chloride to a concentration of 50 mM. Using a calibration curve with polyethylene glycol standards, the sample was dissolved at a concentration of 10 mg / mL for the hydrolyzed polymer polymer, and the clear solution was filtered through a syringe filter with a pore size of 0.22 μm to remove any foreign matter, and the sample was measured.

[0087] [Examples 2-8, 15-23] The polymer polymers of Examples 2-8 and 15-23 were obtained by the same procedure as in Example 1, except that the proportions of materials a-f shown in Table 1 were changed to the amounts shown in Table 2 below.

[0088] (1) Preparation of gel particle dispersions and measurement of dynamic light scattering For each polymer obtained in Examples 2 to 8 and 15 to 23, gel particle dispersions were prepared in the same manner as in Example 1, and dynamic light scattering was measured. The results are summarized in Table 3 below.

[0089] (2) Formation of a lump gel The amount of polymer (not a hydrolyzate) and ion-exchanged water mixed was changed to the amount shown in Table 4 below, and the water / polymer ratio was changed to the amount shown in Table 4 below, except that the same procedure as in Example 1 was followed to form lump gels with each polymer from Examples 2-8 and 15-23, and their (2-1) fluidity and (2-2) transparency were observed. The results are summarized in Table 4 below.

[0090] (3) Hydrolysis of polymer polymers The polymer polymers obtained in Examples 2-8 and 15-23 were hydrolyzed in the same manner as in Example 1. At this time, the concentration and amount of sodium hydroxide aqueous solution β were set so that the amount of sodium hydroxide for each example was calculated in the same manner as in Example 1. In this way, hydrolyzed products of the polymer polymers in Examples 2-8 and 15-23 were obtained.

[0091] For the hydrolysates of each polymer obtained in Examples 2-8 and 15-23, the same procedure as in Example 1 was followed (3-1). １ ¹H-NMR spectra were measured, and the weight-average molecular weight Mw was measured by (3-2) GPC. The results are summarized in Table 3 below. For the aggregate gels formed from the polymer polymers of Examples 2 and 5, as in Example 1, Figures 2(a) and 3(a) show photographs of the aggregate gel immediately after formation, Figures 2(b) and 3(b) show photographs of the aggregate gel after the fluidity test, and Figures 2(c) and 3(c) show photographs for evaluating transparency.

[0092] [Examples 9-11, 14] The polymer polymers of Examples 9-11 and 14 were obtained by following the same procedure as in Example 1, except that the proportions of materials a-f shown in Table 1 were changed to the amounts shown in Table 2 below, and the reaction was carried out using a 25 mL round-bottom flask instead of a reaction tube.

[0093] For each polymer obtained in Examples 9-11 and 14, the following steps were taken in the same manner as in Examples 2-8 and 15-23: "(1) Preparation of a dispersion of gel particles and measurement of dynamic light scattering", "(2) Formation of a lump gel" followed by "(2-1) Fluidity" and "(2-2) Transparency", and "(3) Hydrolysis of the polymer" followed by "(3-1) １The operations for "Measurement of H-NMR spectrum" and "(3-2) Measurement of weight-average molecular weight Mw by GPC" (preparation, formation, measurement, observation, etc.) were performed. The results are summarized in Tables 3 and 4 below. For the aggregate gels formed from each polymer polymer in Examples 9 and 14, as in Example 1, Figures 4(a) and 5(a) show photographs of the aggregate gel immediately after formation, Figures 4(b) and 5(b) show photographs of the aggregate gel after the flowability test, and Figures 4(c) and 5(c) show photographs for evaluating transparency.

[0094] [Example 12] 0.549 g (3.00 mM) of monomer b, 0.883 g (2.99 mM) of monomer a, and 5.00 mL of a mixed solvent of chloroform and ethanol in a volume ratio of 6:4 were added to a glass reaction tube with an outer diameter of 21 mm and a length of 120 mm. The solution was stirred with a magnetic stirrer to dissolve the monomers, and the mixture was then bubbled with nitrogen for 12 minutes.

[0095] Subsequently, 1.00 mL of a solution in which radical polymerization initiator d was dissolved in the above mixed solvent at a concentration of 0.49 mg / mL was added, the reaction tube was sealed, and the mixture was heated in an oil bath at 59°C for 24 hours while stirring to allow the reaction to proceed. Next, the reaction mixture was added dropwise to 300 mL of stirred chloroform to precipitate, and the mixture was filtered through filter paper. The solid remaining on the filter paper was placed in a plastic container, and the solvent was removed under reduced pressure using a vacuum pump for 24 hours or more until a certain weight was obtained. The product obtained as a roughly powdered substance was then ground into a fine powder using a mortar and pestle to obtain the polymer polymer of Example 12.

[0096] The polymer obtained in Example 12 was subjected to the same procedures as in Examples 2-8 and 15-23, specifically "(1) Preparation of a dispersion of gel particles and measurement of dynamic light scattering," "(2) Formation of a lump gel," followed by "(2-1) Fluidity" and "(2-2) Transparency," and "(3) Hydrolysis of the polymer," followed by "(3-1) １The operations for "Measurement of H-NMR spectrum" and "(3-2) Measurement of weight-average molecular weight Mw by GPC" (preparation, formation, measurement, observation, etc.) were performed. The results are summarized in Tables 3 and 4 below. For the mass gel formed by the polymer polymer of Example 12, as in Example 1, Figure 6(a) shows a photograph of the mass gel immediately after formation, Figure 6(b) shows a photograph of the mass gel after the fluidity test, and Figure 6(c) shows a photograph for evaluating transparency.

[0097] [Example 13] In Example 12, the polymer polymer of Example 13 was obtained by following the same procedure as in Example 12, except that the composition of materials a to f shown in Table 1 above was the same as in Example 12, except that the weighing error was kept as shown in Table 2 below, and the reaction time was extended from 24 hours to 48 hours.

[0098] The polymer obtained in Example 13 was subjected to the same procedures as in Examples 2-8 and 15-23, specifically "(1) Preparation of a dispersion of gel particles and measurement of dynamic light scattering," "(2) Formation of a lump gel," followed by "(2-1) Fluidity" and "(2-2) Transparency," and "(3) Hydrolysis of the polymer," followed by "(3-1) １ The procedures for "Measurement of H-NMR spectrum" and "(3-2) Measurement of weight-average molecular weight Mw by GPC" (preparation, formation, measurement, observation, etc.) were performed. The results are summarized in Tables 3 and 4 below.

[0099] [Comparative Example 1] 0.549 g (3.00 mM) of monomer b, 0.886 g (3.00 mM) of monomer a, and 5.00 mL of chloroform were added to a glass reaction tube with an outer diameter of 21 mm and a length of 120 mm. The solution was stirred with a magnetic stirrer to dissolve the monomers, and the mixture was then bubbled with nitrogen for 12 minutes.

[0100] Subsequently, 1.00 mL of a solution of radical polymerization initiator d dissolved in chloroform at a concentration of 0.49 mg / mL was added, the reaction tube was sealed, and the mixture was heated in an oil bath at 59°C for 24 hours while stirring to allow the reaction to proceed. The product that precipitated as a solid was then filtered through filter paper. The solid remaining on the filter paper was placed in a plastic container, and the solvent was removed under reduced pressure using a vacuum pump for 24 hours or more until a certain weight was obtained. The product, which was mostly obtained as a powder, was then ground into a fine powder using a mortar and pestle to obtain the polymer polymer of Comparative Example 1.

[0101] The polymer obtained in Comparative Example 1 was subjected to the same procedures as in Examples 2-8 and 15-23, specifically "(1) Preparation of a dispersion of gel particles and measurement of dynamic light scattering," "(2) Formation of a lump gel," and "(2-1) Fluidity" and "(2-2) Transparency," as well as "(3) Hydrolysis of the polymer," as described in "(3-1) １ Each step of the "H-NMR spectrum measurement" procedure (preparation, formation, measurement, observation, etc.) was performed. The results are summarized in Tables 3 and 4 below. For the aggregate gel formed by the polymer polymer of Comparative Example 1, as in Example 1, Figure 7(a) shows a photograph of the aggregate gel immediately after formation, Figure 7(b) shows a photograph of the aggregate gel after the fluidity test, and Figure 7(c) shows a photograph for evaluating transparency.

[0102] Regarding "(3) Hydrolysis of polymer polymers" followed by "(3-2) Measurement of weight-average molecular weight Mw by GPC," the procedure was carried out in the same manner as in Examples 2-8 and 15-23. However, the polymer polymer of Comparative Example 1 did not produce a hydrolyzed product, and GPC measurement could not be performed.

[0103] [Comparative Examples 2-3] The polymer polymers of Comparative Examples 2-3 were obtained using the same procedure as in Comparative Example 1, except that the proportions of materials a-f shown in Table 1 were changed to the amounts shown in Table 2 below.

[0104] For the obtained comparative examples 2-3 polymers, the following steps were taken in the same manner as in Examples 2-8 and 15-23: "(1) Preparation of a dispersion of gel particles and measurement of dynamic light scattering", "(2) Formation of a lump gel" followed by "(2-1) Fluidity" and "(2-2) Transparency", and "(3) Hydrolysis of the polymer" followed by "(3-1) １Each step of the "H-NMR spectrum measurement" procedure (preparation, formation, measurement, observation, etc.) was performed. The results are summarized in Tables 3 and 4 below. For the aggregate gel formed by the polymer polymer of Comparative Example 3, as in Example 1, Figure 8(a) shows a photograph of the aggregate gel immediately after formation, Figure 8(b) shows a photograph of the aggregate gel after the fluidity test, and Figure 8(c) shows a photograph for evaluating transparency.

[0105] For "(3) Hydrolysis of polymer polymers" followed by "(3-2) Measurement of weight-average molecular weight Mw by GPC," the procedure was carried out in the same manner as in Examples 2-8 and 15-23. However, the polymer polymers in Comparative Examples 2-3 did not produce hydrolyzed products, and GPC measurement was not possible.

[0106] [Comparative Examples 4-7] The polymer polymers of Comparative Examples 4-7 were obtained using the same procedure as in Example 1, except that the proportions of materials a-f shown in Table 1 were changed to the amounts shown in Table 2 below.

[0107] For each of the obtained comparative examples 4 to 7 polymers, the following steps were taken in the same manner as in Example 1: "(1) Preparation of a dispersion of gel particles and measurement of dynamic light scattering," "(2) Formation of a lump gel" followed by "(2-1) Fluidity" and "(2-2) Transparency," and "(3) Hydrolysis of the polymer" followed by "(3-1) １ The procedures for "Measurement of H-NMR spectrum" and "(3-2) Measurement of weight-average molecular weight Mw by GPC" (preparation, formation, measurement, observation, etc.) were performed. The results are summarized in Tables 3 and 4 below.

[0108] Furthermore, in the GPC measurement of the hydrolyzed polymers of Comparative Examples 6 and 7, the solutions were slightly cloudy and could not be filtered using a syringe filter with a pore size of 0.22 μm. However, a sample that could be used for GPC measurement was obtained using a syringe filter with a pore size of 0.45 μm, albeit at high pressure. Therefore, for Comparative Examples 6 and 7, the molecular weights listed in Table 3 may not represent all of the copolymers.

[0109]

[0110] In Table 2 above, the symbols a to f refer to the respective materials in Table 1. Also, in Table 2 above, the "solvent" column shows the volume ratio (e / f) of chloroform e to ethanol f of the solvent used.

[0111]

[0112] In Table 3 above, the "monomer charging ratio (molar ratio)" is the calculated charging ratio (molar ratio) of monomer a and monomer b obtained from the mass-based blending of monomers shown in Table 2. On the other hand, the "measured value ( １ The ¹H-NMR (molar ratio of structural units) is used for each example and comparative example of polymer polymers. １ This is the molar ratio of structural units derived from monomer a to structural units derived from monomer b, as measured by 1H-NMR spectroscopy.

[0113]

[0114] [Discussion of the results of the examples and comparative examples] In Examples 1 to 23, as shown in Table 3 above, the monomer ratio (a / b ratio) in the polymer polymer was as follows, relative to the charging ratio of monomers a and b: １ The results, including the measurement error of H-NMR, closely reflected the initial charge ratio. In contrast, in Comparative Examples 1 to 3, the monomer ratio in the polymer (a / b ratio) deviated considerably from the initial charge ratio of monomers a and b, indicating that the reaction was not controlled.

[0115] The weight-average molecular weight Mw of the polymers in Examples 1 to 23 was in the range of 10,900 to 148,000, as shown in Table 3 above. However, the polymers in Comparative Examples 1 to 3 did not dissolve in the GPC solvent and could not be measured. Therefore, it is estimated that their weight-average molecular weight exceeds 400,000.

[0116] As shown in Table 3 above, the particle sizes of the polymer polymers in Examples 2-12 and 15-21, determined by dynamic light scattering, were in the range of 5-12 nm for the main peaks accounting for 99.5% or more of the total. In Example 1, the average particle size of the peak accounting for 98.9% by volume was 4.4 nm, and the average particle size of the peak accounting for 1.05% by volume was 15.7 nm. In Example 13, 0.19% of the peaks had an average particle size of 1030 nm, and in Example 14, peaks with average particle sizes of 900 nm and 3900 nm accounted for 96.9% and 2%, respectively. In Example 22, peaks with average particle sizes of 35 nm and 410 nm accounted for 72% and 27.6%, respectively, and in Example 23, peaks with average particle sizes of 17.4 nm and 190 nm accounted for 39.4% and 2.74%, respectively.

[0117] The dispersions subjected to dynamic light scattering were transparent to the naked eye except for Examples 19 and 26, in which case they were slightly cloudy. In contrast, the dispersions subjected to dynamic light scattering in Comparative Examples 1 to 3 contained numerous white particles. No peaks were observed up to the upper limit of measurement of 10,000 nm in Comparative Examples 1 and 2, and a peak was observed at 5,000 nm in Comparative Example 3, but no peaks were observed below 1,000 nm. Furthermore, it was unclear whether the 5,000 nm peak observed in Comparative Example 3 represented all particles with a particle size of 10,000 nm or less.

[0118] The weight-average molecular weight Mw of the polymers in Comparative Examples 4-7 ranged from 2500 to 12000, which was relatively lower than that of the polymers in the Examples. However, the dispersions subjected to dynamic light scattering were turbid, and particle precipitation was observed. Dynamic light scattering showed peaks at average particle sizes of 3000-4500 nm, but it was unclear whether these represented all particles with a particle size of 10000 nm or less.

[0119] As shown in Table 4 and the photographs above, transparent solid gels were obtained in Examples 1-13 and 15-21, while semi-transparent solid gels were obtained in Examples 14, 22, and 23, with Example 23 exhibiting particularly low transparency. In contrast, opaque white gels were obtained in Comparative Examples 1-3. Comparative Examples 4-7 were opaque, paste-like mixtures of powder and water, and did not form hydrogels.

Claims

1. A polymer polymer which is a homopolymer consisting of a monomer unit (A) having a zwitterionic group, or a copolymer consisting of the monomer unit (A) and other monomer units (B), wherein the weight-average molecular weight obtained by gel permeation chromatography using a mixed solvent of water and methanol as the eluent and polyethylene glycol as the standard sample is 400,000 or less, and the other monomer unit (B) is a monomer unit (B') containing an N-succinimide ester group.

2. A polymer polymer which is a homopolymer consisting of monomer units (A) having zwitterionic groups, or a copolymer consisting of the monomer unit (A) and other monomer units (B), wherein the weight-average molecular weight measured by gel permeation chromatography using a mixed solvent of water and methanol as the eluent and polyethylene glycol as the standard sample is 400,000 or less, and in a dispersion of 1 mL of water added to 10 mg of the polymer polymer, gel particles are formed, and in the dynamic light scattering of the gel particles, the volume fraction of the peak with an average particle size of 1,000 nm or less is 30% or more, and the maximum diameter of the gel particles is 10,000 nm or less.

3. The polymer polymer according to claim 2, wherein the volume fraction of the peak with an average particle size of 1000 nm or less in the dynamic light scattering of the gel particles is 95% or more.

4. The polymer polymer according to claim 2, wherein the other monomer unit (B) is a monomer unit (B') containing an N-succinimide ester group.

5. The polymer polymer according to claim 1 or 2, wherein the molar ratio of monomer unit (A) to monomer unit (B) [(A):(B)] is in the range of 100:0 to 20:

80.

6. The polymer polymer according to claim 1 or 2, wherein when at least one amount of water in the range of 0.5 mL to 2.0 mL is added to 1 g of the polymer polymer, it does not exhibit fluidity and forms a transparent or translucent gel mass.

7. The polymer polymer according to claim 1 or 2, wherein the zwitterionic group is any functional group selected from the group consisting of a phosphobetaine group, a sulfobetaine group, and a carboxybetaine group.

8. The monomer unit (A) is of the following formula (I) (wherein R １ R represents a linear or branched alkyl group having 1 to 5 carbon atoms. ２ R represents a linear or branched alkylene group having 1 to 20 carbon atoms. ５ R represents a directly bonded or linear or branched alkylene group having 1 to 20 carbon atoms. The monomer unit (B) has the structure of the following formula (II) (wherein R ３ R represents a linear or branched alkyl group having 1 to 5 carbon atoms. ４ The polymer polymer according to claim 1 or 2, having the structure of (where represents a directly bonded or linear or branched alkylene group having 1 to 5 carbon atoms).

9. A gel dispersion obtained by adding water to the polymer polymer according to claim 1 or 2.

10. A transparent or translucent gel mass obtained by adding water to the polymer polymer according to claim 1 or 2.

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