Polymer, method for producing polymer, electrolyte composition, and battery

Abstract

To provide a polymer with high dielectric strength on the oxidation side.SOLUTION: A polymer comprises a monomer unit (A) having a maleimide structural unit and a -SO2-N-M+-SO2- structural unit, and a monomer unit having a second structural unit. Relative to all the structural units present in the polymer, the proportion "m" of the structural unit (A) is 0.2-0.8 and the proportion "n" of the second structural unit is 0.2-0.8.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to polymers, methods for producing polymers, electrolyte compositions, and batteries. [Background technology]

[0002] Lithium-ion batteries and similar devices are being actively researched due to their high capacity. While solutions of lithium salts containing organic solvents or ionic liquids are known as electrolytes for lithium-ion batteries, research on solid electrolytes is progressing from the perspective of safety and processability, and among these, polymers containing lithium ions are attracting particular attention for the following reasons (Patent Document 1, and Non-Patent Documents 1 and 2).

[0003] In other words, lithium-ion-containing polymers have the advantage of being highly flexible, which facilitates contact within solid electrolytes and at the interface with electrodes. Furthermore, by using lithium-ion counteranions as functional groups in the polymer, the anions can be fixed to the polymer, suppressing the movement of ions other than lithium ions during charging and discharging, effectively making lithium ions the sole charge element (i.e., they can be used as single-ion conductors (SIC)). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Chinese Patent Application Publication No. 108878777 Specification [Non-patent literature]

[0005] [Non-Patent Document 1] Li et al., "Single ion conducting lithium sulfur polymerbatteries with improved safety and stability", Journal of MaterialsChemistry A, 2018, 6, p.14330-14338. [Non-Patent Document 2] Du et al., "Water-Insoluble Side-Chain-Grafted Single IonConducting Polymer Electrolyte for Long-Term Stable Lithium Metal Secondary Batteries", ACS Applied Energy Materials, 2020, 3, p.1128-1138. [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the lithium-ion polymers described in Patent Document 1 and Non-Patent Documents 1 and 2 have an oxidation potential of approximately 4.4V, indicating room for improvement in their oxidative voltage resistance. To be combined with electrodes of higher potential, the development of polymers with superior oxidative voltage resistance is desired.

[0007] This invention has been made in view of the above circumstances, and aims to provide a polymer with excellent voltage resistance on the oxidation side. Furthermore, this invention also aims to provide a method for producing a polymer with excellent voltage resistance on the oxidation side. Moreover, this invention also aims to provide an electrolyte composition and a battery containing such a polymer. [Means for solving the problem]

[0008] The polymer of the present invention comprises a first structural unit which is at least one of the structural units (A) represented by the following formula (A), and a second structural unit which is at least one of the structural units (B1) represented by the following formula (B1) and the structural unit (B2) represented by the following formula (B2), and satisfies at least one of the following conditions (1) and (2). (1) The ratio m of the first structural unit to the total structural units contained in the polymer is 0.2 to 0.8, and the ratio n of the second structural unit to the total structural units contained in the polymer is 0.2 to 0.8. (2) The content of the first structural unit is 25 to 95% by mass of the total mass of the polymer, and the content of the second structural unit is 5 to 75% by mass. [ka] (In formula (A), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, M is an alkali metal element selected from Li, Na, and K, and * indicates the position where structural unit (A) bonds with other structural units.) [ka] (In equation (B1), R 1 ~R 4 Each of these is a monovalent organic group, independently containing a hydrogen atom, a halogen atom, and 1 to 20 carbon atoms. * indicates the position where structural unit (B1) bonds with other structural units. [ka] (In formula (B2), R 15 R is a divalent organic group having 1 to 20 carbon atoms. 16 and R 17 These are monovalent organic groups having a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms, respectively. However, structural unit (B2) has R 15 is -C(=O)-OC(=O)- and R 16 and R17 None of them is a structural unit of a hydrogen atom, and the structural unit contained in the structural unit (A) is not included.)

[0009] It is preferable that the molar ratio of the structural unit (C) represented by the following formula (C) to the first structural unit in the polymer is 5 / 95 or less.)

Chemical formula

[0010] The oxidation potential of the polymer is preferably 4.5 V or more based on the Li / Li + electrode.)

[0011] It is preferable that the second structural unit contains the structural unit (D) represented by the following formula (D).)

Chemical formula

[0012] It is preferable that the molar ratio of the structural unit (A) to the total number of moles of the structural unit (A) and the structural unit (B1) is greater than 0.40.)

[0013] The polymer of the present invention is a polymer containing a structural unit (A) represented by the following formula (A), and the molar ratio of the structural unit (C) represented by the following formula (C) to the structural unit (A) in the polymer may be 5 / 95 or less.)

Chemical formula

[0014] The electrolyte composition of the present invention comprises the above polymer.

[0015] The above electrolyte composition preferably further contains a plasticizer.

[0016] The plasticizer is preferably an organic solvent.

[0017] The battery of the present invention comprises the above polymer or the above electrolyte composition.

[0018] The present invention provides a polymer production method comprising the step of polymerizing a monomer comprising a monomer (A') represented by the following formula (A') and a second monomer containing at least one of a monomer (B1') represented by the following formula (B1') and a monomer (B2') represented by the following formula (B2'). [ka] (In formula (A'), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, and M is an alkali metal element selected from Li, Na, and K.) [ka] (In equation (B1'), R 1 ~R 4 Each of these is a monovalent organic group, independently containing a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms. [ka] (In formula (B2'), R 15 R is a divalent organic group having 1 to 20 carbon atoms. 16 and R 17 Each of these is a monovalent organic group having a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms. However, monomer (B2') does not contain maleic anhydride, nor the monomers contained in monomer (A').

[0019] The polymer of the present invention may be obtained by polymerizing a monomer (A') represented by the following formula (A') and a second monomer containing at least one of the monomer (B1') represented by the following formula (B1') and the monomer (B2') represented by the following formula (B2'). [ka] (In formula (A'), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, and M is an alkali metal element selected from Li, Na, and K.) [ka] (In equation (B1'), R 1 ~R 4 Each of these is a monovalent organic group, independently containing a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms. [ka] (In formula (B2'), R 15 R is a divalent organic group having 1 to 20 carbon atoms. 16 and R 17 Each of these is a monovalent organic group having a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms. However, monomer (B2') does not contain maleic anhydride, nor the monomers contained in monomer (A'). [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a polymer with excellent voltage resistance on the oxidation side. Furthermore, according to the present invention, it is possible to provide a method for producing a polymer with excellent voltage resistance on the oxidation side. Moreover, according to the present invention, it is possible to provide an electrolyte composition and a battery containing such a polymer. [Modes for carrying out the invention]

[0021] (First embodiment)

[0022] A polymer comprising a first structural unit (A) represented by the following formula (A), and a second structural unit (B1) represented by the following formula (B1) and a structural unit (B2) represented by the following formula (B2), wherein the polymer satisfies at least one of the following conditions (1) and (2). (1) The ratio m of the first structural unit to the total structural units contained in the polymer is 0.2 to 0.8, and the ratio n of the second structural unit to the total structural units contained in the polymer is 0.2 to 0.8. (2) The content of the first structural unit is 25 to 95% by mass of the total mass of the polymer, and the content of the second structural unit is 5 to 75% by mass. [ka] (In formula (A), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, M is an alkali metal element selected from Li, Na, and K, and * indicates the position where structural unit (A) bonds with other structural units.) [ka] (In equation (B1), R 1 ~R 4Each of these is a monovalent organic group, independently containing a hydrogen atom, a halogen atom, and 1 to 20 carbon atoms. * indicates the position where structural unit (B1) bonds with other structural units. [ka] (In formula (B2), R 15 R is a divalent organic group having 1 to 20 carbon atoms. 16 and R 17 These are monovalent organic groups having a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms, respectively. However, structural unit (B2) has R 15 is -C(=O)-OC(=O)- and R 16 and R 17 None of these include structural units that are hydrogen atoms, nor structural units that are included in structural unit (A). Such polymers exhibit high dielectric strength on the oxidation side.

[0023] m is preferably 0.3 to 0.7, and more preferably 0.4 to 0.6. n is preferably 0.3 to 0.7, and more preferably 0.35 to 0.65.

[0024] The value of m / (m+n) is preferably greater than 0.40, more preferably 0.41 or greater, even more preferably 0.45 or greater, and particularly preferably between 0.45 and 0.65.

[0025] The sum of m and n is acceptable as long as it is 1 or less, but for example, it can be between 0.5 and 0.95, or between 0.6 and 0.90.

[0026] The content of structural unit (A) relative to the total mass of the polymer may be 40 to 90% by mass, or 50 to 90% by mass. The content of the second structural unit relative to the total mass of the polymer may be 10 to 60% by mass, or 10 to 50% by mass. The combined content of structural unit (A) and the second structural unit relative to the total mass of the polymer may be 90% by mass or more, 95% by mass, or 98% by mass or more.

[0027] The content of structural unit (B1) relative to the total mass of the polymer may be 10 to 60% by mass, or 10 to 50% by mass. The combined content of structural unit (A) and structural unit (B1) relative to the total mass of the polymer may be 90% by mass or more, 95% by mass, or 98% by mass or more.

[0028] In the polymer, the molar ratio of structural unit (A) to the total number of moles of structural unit (B1) is preferably greater than 0.40, more preferably 0.41 or greater, even more preferably 0.45 or greater, and particularly preferably 0.45 to 0.65.

[0029] X is not particularly limited and may be a hydrocarbon group, a group having a heteroatom, or a heterocycle. More specifically, X may be a hydrocarbon group, or a divalent group having a chemical structure in which one or more carbon atoms (methylene groups) in a hydrocarbon group are substituted by linking groups of -O-, -S-, -C(=O)-, or -C(=O)O-. If there are multiple linking groups, they are not adjacent to each other. Furthermore, the above divalent group may have substituents that substitute for hydrogen atoms bonded to carbon atoms. The substituents may be monovalent substituents, such as halogen atoms. The above hydrocarbon group is not particularly limited and may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be a linear hydrocarbon group, a branched hydrocarbon group, or a cyclic hydrocarbon group. Furthermore, the hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. X may be bonded by its carbon atoms to one or both of the nitrogen atoms of the two maleimide groups and the sulfur atoms of the sulfonyl group.

[0030] In this specification, an aromatic hydrocarbon group is a group containing an aromatic moiety and may also have an aliphatic moiety. In this specification, a cyclic hydrocarbon group is a group containing a cyclic hydrocarbon moiety and may also contain a linear or branched hydrocarbon moiety.

[0031] The number of carbon atoms in X may be 1 to 15, 2 to 10, or 3 to 8. X may be a group having an aromatic ring, or a group having an aromatic carbon ring such as a benzene ring. Substituents such as alkyl groups, halogen atoms, or electron-withdrawing groups may be bonded to the carbon atoms that are members of the carbon ring. The hydrocarbon group as X is preferably a phenylene group, an alkylene group having 1 to 8 carbon atoms, a polyoxyalkylene group, or a group in which some or all of the hydrogen atoms bonded to the carbon atoms thereon are substituted with halogen atoms such as fluorine atoms, and more preferably a substituted phenylene group substituted with an alkyl group, halogen atom, electron-withdrawing group, etc. Examples of electron-withdrawing groups include halogen atoms, sulfonic acid groups or their salts, sulfonic acid esters, nitro groups, and nitrile groups.

[0032] In formula (A), if Y is a monovalent organic group, there are no particular restrictions on the organic group, and it may be a hydrocarbon group, a group having a heteroatom, or a heterocycle. More specifically, Y can be a monovalent group such as a hydrocarbon group or a group having a chemical structure in which one or more carbon atoms (methylene groups) in the hydrocarbon group are substituted by linking groups of -O-, -S-, -C(=O)-, or -C(=O)O-. If there are multiple linking groups, the linking groups are not adjacent to each other. Furthermore, the above monovalent group may have substituents that substitute for hydrogen atoms bonded to carbon atoms. The substituents may be monovalent substituents, such as halogen atoms. The above hydrocarbon group is not particularly limited and may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be a linear hydrocarbon group, a branched hydrocarbon group, or a cyclic hydrocarbon group. Furthermore, the hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group.

[0033] The number of carbon atoms in Y may be 1 to 15, 1 to 10, 1 to 8, 1 to 5, or 1 to 3. The hydrocarbon group as Y is preferably a phenyl group, an alkyl group having 1 to 5 carbon atoms, or a group in which some or all of the hydrogen atoms bonded to the carbon atoms are substituted with halogen atoms such as fluorine atoms. A fluorinated alkyl group having 1 to 5 carbon atoms is more preferred, and a fluorinated alkyl group having 1 to 3 carbon atoms such as a trifluoromethyl group is even more preferred. The fluorinated alkyl group may be a total fluorinated alkyl group. When Y is a halogen atom, the halogen atom is preferably a fluorine atom or a chlorine atom, with a fluorine atom being more preferred.

[0034] In formula (A), M + It is an alkali metal ion, and lithium ion (Li + ), sodium ions (Na + ), or potassium ions (K + It is preferable that it is lithium ion, and more preferably M + Li + na + , and K + It may contain two or three types of ions, but it is preferable to contain substantially only a single ion.

[0035] In equation (B1), R 1 ~R 4 These may be identical or different from one another. 1 ~R 4 If at least one of them is a monovalent organic group, there are no particular restrictions on the organic group, and it may be a hydrocarbon group, a group having a heteroatom, or a heterocycle. 1 ~R 4More specifically, examples include monovalent groups such as hydrocarbon groups and groups having a chemical structure in which one or more carbon atoms (methylene groups) in a hydrocarbon group are substituted by linking groups of -O-, -S-, -C(=O)-, or -C(=O)O-. If there are multiple linking groups, they are not adjacent to each other. Furthermore, the above monovalent groups may have substituents that substitute for hydrogen atoms bonded to carbon atoms. Examples of substituents include halogen atoms. The above hydrocarbon groups are not particularly limited and may be aliphatic hydrocarbon groups or aromatic hydrocarbon groups. Aliphatic hydrocarbon groups may be linear hydrocarbon groups, branched hydrocarbon groups, or cyclic hydrocarbon groups. Furthermore, the hydrocarbon groups may be saturated hydrocarbon groups or unsaturated hydrocarbon groups.

[0036] R 1 ~R 4 Preferably, at least one of them is a hydrogen atom, preferably two or more are hydrogen atoms, and preferably three are hydrogen atoms. 1 ~R 4 If at least one of them is a halogen atom, the halogen atom is preferably a chlorine atom or a fluorine atom, and more preferably a fluorine atom.

[0037] Examples of monovalent organic groups include the group represented by the formula -ZR, where Z is a covalent bond, -O-, -S-, -C(=O)-, or -C(=O)O-, and R is a monovalent organic group. 1 ~R 4 At least one of these groups may be represented by -ZR. If Z is not a covalent bond, R is a group that bonds to Z via the carbon atoms it possesses; if Z is a covalent bond, R is a group that directly bonds to the carbon atoms of the ethylene portion in formula (B1) via the carbon atoms it possesses.

[0038] The number of carbon atoms in R is preferably 1 to 18, more preferably 2 to 15, and even more preferably 3 to 13.

[0039] R is a substituted or unsubstituted hydrocarbon group, or formula:-(R24 O) k -R 25 The group may be represented by . Examples of hydrocarbon groups include linear or branched alkyl groups, cyclohexyl groups, benzyl groups, and other groups having a carbon ring (which may be either aliphatic or aromatic). Examples of substituted hydrocarbon groups include those obtained by replacing some or all of the hydrogen atoms in the above hydrocarbon group with halogen atoms (fluorine atoms are preferred).

[0040] In the formula, k may be 1 to 6, 1 to 5, or 1 to 4. 24 R may be a substituted or unsubstituted alkylene group having 1 to 3 carbon atoms, or an ethylene group. 24 If R has 24 These may all be the same, or they may be two or more types of alkylene groups. 24 If R is a substituted alkylene group, 24 R 24 When the alkylene group is an alkylene group, it is preferable that the hydrogen atoms of the alkylene group exemplified are substituted with substituents. The substituents may be halogen atoms such as fluorine atoms.

[0041] R 25 R may be a substituted or unsubstituted hydrocarbon group having 1 to 6 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms, a substituted or unsubstituted ethyl group, or a substituted or unsubstituted methyl group. 25 If R is a substituted hydrocarbon group, 25 R 25 When the hydrocarbon group is an example, it is preferable that the hydrogen atoms of the hydrocarbon group are substituted with substituents. The substituents may be halogen atoms such as fluorine atoms.

[0042] When R is a hydrocarbon group, the hydrocarbon group may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be any of a linear hydrocarbon group, a branched hydrocarbon group, or a cyclic hydrocarbon group. Furthermore, the hydrocarbon group may be either a saturated hydrocarbon group or an unsaturated hydrocarbon group. Specific examples of R include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, phenyl group, benzyl group, etc. When R is a substituted hydrocarbon group, it is preferable that R is a hydrocarbon group exemplified when R is a hydrocarbon group, with the hydrogen atoms replaced by substituents. The substituent may be a halogen atom such as a fluorine atom.

[0043] It is preferable that the structural unit (B1) includes a structural unit (D) represented by the following formula (D). [ka] (Z is a covalent bond, -O-, -S-, -C(=O)-, -C(=O)O-, or -OC(=O)-, R 21 is a monovalent organic group, R 22 (* represents a hydrogen atom or a monovalent hydrocarbon group.)

[0044] R 22 If it is a monovalent hydrocarbon group, the number of carbon atoms in the hydrocarbon group is preferably 1 to 10, preferably 1 to 5, and preferably 1 to 3. 22 This may be a hydrogen atom or a methyl group.

[0045] Z is preferably a covalent bond, -O-, -C(=O)O-, or -OC(=O)-, more preferably a covalent bond or -O-, and even more preferably -O-.

[0046] R 21It is preferable that R is as exemplified above in the -ZR group.

[0047] Structural unit (B1) may include structural units other than structural unit (D). For example, structural unit (E) represented by the following formula (E) can be mentioned. [ka] (In formula (E), R 11 ~R 14 These are, independently, a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, -C(=O)OH, and -CN, or -C(=O)NR. 31 (R 31 ( is a hydrogen atom or an organic group.) (It is a monovalent group.) * indicates the bonding position of structural unit (E) with other structural units.

[0048] R 31 If R is an organic group, 31 It is preferable that the hydrocarbon group is substituted or unsubstituted. The number of carbon atoms in the substituted or unsubstituted hydrocarbon group is preferably 1 to 18, more preferably 1 to 15, even more preferably 1 to 10, and particularly preferably 1 to 5.

[0049] Furthermore, the polymer may contain structural units (B2) represented by the following formula (B2). [ka] (In formula (B2), R 15 R is a divalent organic group having 1 to 20 carbon atoms. 16 and R 17 These are, respectively, monovalent organic groups having a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms.

[0050] R 15 The number of carbon atoms contained in is preferably 2 to 10, more preferably 2 to 6, and even more preferably 3 to 5. 15may contain at least one divalent group selected from the group consisting of -O-, -S-, -C(=O)-, -C(=O)O-, -C(=O)-O-C(=O)-, and -C(=O)-N(R 35 ). Here, R 35 is a monovalent organic group. When R 15 contains a plurality of such divalent groups, the plurality of divalent groups are not adjacent to each other. Further, R 15 may have a hydrocarbon moiety or a substituted hydrocarbon moiety in which a hydrogen atom of the hydrocarbon moiety is substituted with a substituent in addition to the above divalent group. Examples of the substituent include a halogen atom and the like. The hydrocarbon group is not particularly limited and may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be any of a linear hydrocarbon group, a branched hydrocarbon group, and a cyclic hydrocarbon group. Further, the hydrocarbon group may be either a saturated hydrocarbon group or an unsaturated hydrocarbon group.

[0051] [[ID=!12]]R 15 may have 1 to 15 carbon atoms, may have 2 to 10 carbon atoms, may have 2 to 8 carbon atoms, or may have 3 to 6 carbon atoms. The hydrocarbon group as R 15 is preferably an alkylene group having 1 to 8 carbon atoms, a polyalkyleneoxy group, or a group in which some or all of the hydrogen atoms bonded to the carbon atoms thereof are substituted with a halogen atom such as a fluorine atom.

[0052] R 16 and R 17 When they are organic groups, specific examples of the organic group include those exemplified as specific examples of R 1 to R 4 .

[0053] The structural unit (B2) is a group different from the structural unit (A). That is, the structural unit contained in the above structural unit (A) is not contained in the structural unit (B2). When R 15 is a -C(=O)-N(R 35 )-C(=O)- group, R 35 is -X-SO2-N - It should be noted that in the original text, there seems to be a "!12" which might be an error. It is translated as "R" in the English version as it's not clear what else it could be. If this is a specific symbol or has a different meaning in the original context, the translation might need to be adjusted accordingly.M + -SO2-Y (X, M, and Y have the same meanings as X, M, and Y in formula (A).) may be used, but in that case, R 16 and R 17 at least one of them is a monovalent substituent other than a hydrogen atom. Examples of such substituents include a halogen atom, a monovalent organic group having 1 to 20 carbon atoms, etc. The number of carbon atoms in the monovalent organic group is preferably 1 to 10, and more preferably 1 to 5.

[0054] Structural unit (B2) is a group different from the structural unit (C) described later. In structural unit (B2), R 15 is -C(=O)-O-C(=O)- and neither R 16 nor R 17 is a hydrogen atom. That is, when R 15 is -C(=O)-O-C(=O)-, at least one of R 16 and R 17 is a monovalent substituent other than a hydrogen atom. Examples of such substituents include a halogen atom, a monovalent organic group having 1 to 20 carbon atoms, etc. The number of carbon atoms in the monovalent organic group is preferably 1 to 10, and more preferably 1 to 5.

[0055] R 15 may be a group having 3 to 21 carbon atoms containing at least one of -C(=O)-O-C(=O)- and -C(=O)-N(R 35 )-C(=O)-, -C(=O)-O-C(=O)-, and -C(=O)-N(R 35The structural unit (B2) may be a carbon-3 to carbon-19 group containing at least one of )-C(=O)-. Examples of such groups include structural units derived from maleic anhydride derivatives and structural units derived from maleimide derivatives. Structural unit (B2) may contain at least one of the structural units derived from maleic anhydride derivatives and structural units derived from maleimide derivatives. The structural units derived from maleic anhydride derivatives and structural units derived from maleimide derivatives are structural units having chemical structures that can be directly obtained when maleic anhydride derivatives and maleimide derivatives are radically polymerized, respectively. The molar ratio of the structural unit derived from maleic anhydride derivative to the first structural unit may be 5 / 95 or less.

[0056] R 35 This is a monovalent organic group. The number of carbon atoms in this monovalent organic group may be 1 to 15, 2 to 10, 2 to 8, or 3 to 6.

[0057] R 15 If R is an organic group, 15 The hydrocarbon group may be substituted or unsubstituted. The number of carbon atoms in the substituted or unsubstituted hydrocarbon group is preferably 1 to 18, more preferably 1 to 15, and even more preferably 1 to 10.

[0058] The polymer may contain structural units derived from hydrocarbon compounds having multiple ethylenically unsaturated groups, such as butadiene and isoprene.

[0059] The polymer may have structural units derived from the crosslinking agent. Examples of crosslinking agents include compounds having multiple ethylenically unsaturated groups in their molecules, such as hexanediol diacrylate, pentaerythritol tetraacrylate, divinylbenzene, and triethylene glycol divinyl ether.

[0060] The polymer described above may contain two or more structural units (A), or it may contain only one structural unit (A). Furthermore, the polymer may contain two or more second structural units, or it may contain only one second structural unit. When it contains multiple second structural units, it may contain multiple types of either structural unit (B1) or structural unit (B2), or it may contain one type each of structural unit (B1) and structural unit (B2).

[0061] The number-average molecular weight (Mn) of the polymer may be between 5,000 and 200,000, between 8,000 and 120,000, or between 10,000 and 100,000. The weight-average molecular weight (Mw) of the polymer may be between 5,000 and 300,000, between 10,000 and 250,000, or between 20,000 and 100,000. The molecular weight distribution (Mw / Mn) of the polymer may be between 1.0 and 3.0, or between 1.3 and 2.7. The number-average molecular weight and weight-average molecular weight of the polymer can be measured, for example, by gel permeation chromatography.

[0062] The above polymer may contain, but may not contain, the structural unit (C) represented by the following formula (C). [ka]

[0063] The content of structural unit (C) in the polymer is preferably 5 / 95 or less, more preferably 3 / 97 or less, and even more preferably 1 / 99 or less, in terms of the molar ratio of structural unit (C) to structural unit (A). When the content of structural unit (C) in the polymer is within this range, the dielectric strength on the oxidation side of the polymer tends to be higher. The polymer may not contain substantially any structural unit (C). The polymer may also contain structural units produced by the reaction of structural unit (A) with one or two molecules of water, or structural units produced by the hydrolysis of (C).

[0064] <Method for producing polymers> A polymer production method according to one embodiment of the present invention preferably includes a step of polymerizing a monomer (monomer mixture) comprising a monomer (A') represented by the following formula (A') (also called a first monomer) and a second monomer containing at least one of a monomer (B1') represented by the following formula (B1') and a monomer (B2') represented by the following formula (B2'). Such a polymer production method is suitable for producing the polymer of this embodiment. The second monomer may be used in excess of the desired proportion in the polymer. [ka] (In formula (A'), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, and M is an alkali metal element selected from Li, Na, and K.) [ka] (In equation (B1'), R 1 ~R 4 Each of these is a monovalent organic group having independently a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms. In formula (B2'), R 15 R is a divalent organic group having 1 to 20 carbon atoms. 16 and R 17 These are, respectively, monovalent organic groups having a hydrogen atom, a halogen atom, or 1 to 20 carbon atoms.

[0065] Preferred examples of X, Y, and M in monomer (A') include those exemplified as X, Y, and M of the structural unit (A) of the polymer described above.

[0066] R in monomer (B1') 1 ~R 4 A preferred example is the R of the structural unit (B1) of the polymer. 1 ~R 4Examples include the monomer (B1), which is represented by the monomer (D') shown in the following formula (D'), the monomer (E') shown in the following formula (E'), and so on. [ka]

[0067] In equation (D'), R 22 , Z and R 21 A preferred example is the R of structural unit (D). 22 , Z and R 21 Examples include the following. In equation (E'), R 11 ~R 14 A preferred example is the R of structural unit (E). 11 ~R 14 Examples include the following:

[0068] In equation (E'), R 15 ~R 17 A preferred example is the R of the structural unit (B2). 15 ~R 17 Examples include the following. Monomer (B2') does not contain maleic anhydride, nor any of the monomers contained in monomer (A').

[0069] The monomer (B1') may be an alkyl (meth)acrylic acid ester, an olefin compound, styrene or a styrene derivative, a vinyl ester compound, or a vinyl ether compound, with olefin compounds or vinyl ether compounds being preferred. As for vinyl ether compounds, H2C=CH(OR 41 Examples of compounds given by R 41 is a substituted or unsubstituted hydrocarbon group, or the above formula:-(R 24 O) k -R 25 It may be the basis of R. 41 An example of this is the one exemplified as R above.

[0070] The vinyl ether compound may be an alkyl vinyl ether. Examples of vinyl ether compounds include alkyl vinyl ethers having linear or branched alkyl groups such as methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, t-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-heptyl vinyl ether, n-octyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, n-decyl vinyl ether, n-undecyl vinyl ether, n-dodecyl vinyl ether, and n-tridecyl vinyl ether; vinyl ether compounds having a carbon ring (which may be either aliphatic or aromatic) such as cyclohexyl vinyl ether and benzyl vinyl ether, with isobutyl vinyl ether or n-dodecyl vinyl ether being preferred.

[0071] Furthermore, the vinyl ether compound may be a compound having two or more ether bonds in its molecule, such as tetraethylene glycol methyl vinyl ether, 3,6,9,12,15-pentaoxa-1-heptadecene, and 2-(heptafluoropropoxy)hexafluoropropyl trifluorovinyl ether.

[0072] Examples of styrene derivatives include alkyl-substituted styrenes. The alkyl group as a substituent may be a methyl group or an ethyl group. Examples of alkyl-substituted styrenes include α-methylstyrene, β-methylstyrene (which may be cis, trans, or a mixture thereof), 2-methylstyrene, 3-methylstyrene, and 4-methylstyrene. Other examples of styrene derivatives include alkoxystyrenes such as 4-methoxystyrene and 4-ethoxystyrene; and halogen-substituted styrenes such as 2,3,4,5,6-pentafluorostyrene.

[0073] The polymerizable composition contains monomer (A'), a second monomer, and a radical polymerization initiator. That is, the monomer polymerization reaction takes place in the polymerizable composition and is initiated in the presence of the initiator. If m is the number of moles of monomer (A') relative to the total number of moles of monomers contained in the polymer composition, then m is preferably 0.3 to 0.7 and more preferably 0.4 to 0.6. If n is the number of moles of monomer (B1') relative to the total number of moles of monomers contained in the polymer composition, then n is preferably 0.3 to 0.7 and more preferably 0.4 to 0.6.

[0074] In polymerizable compositions, the value of m / (m+n) is preferably greater than 0.40, more preferably 0.41 or greater, even more preferably 0.45 or greater, and particularly preferably 0.45 to 0.60. The sum of m and n in polymerizable compositions is acceptable as long as it is 1 or less, but may be, for example, 0.5 to 0.95 or 0.6 to 0.90. When monomer (A') and the second monomer are in an electron acceptor-electron donor relationship, the polymer tends to have a primary structure in which structural units (A) and the second structural unit are arranged alternately.

[0075] The radical polymerization initiator may be either a thermal initiator or a photoinitiator. For example, thermal initiators include azo initiators such as 2,2-azobis(isobutyronitrile) (AIBN), 2,2-azobis(2-methylbutyronitrile) (AMBN), 2,2-azobis(2,4-dimethylvaleronitrile) (ADVN), 1,1-azobis(1-cyclohexanecarbonitride) (ACHN, V-40), and dimethyl-2,2-azobisisobutyrate (MAIB); and organic peroxides such as dibenzoyl peroxide, di-8,5,5-trimethylhexanoyl peroxide, dilauroyl peroxide, didecanoyl peroxide, and di(2,4-dichlorobenzoyl) peroxide. Photoinitiators include oxime compounds, metallocene compounds, acylphosphine compounds, and aminoacetophenone compounds. One or more initiators may be used.

[0076] The polymerizable composition may contain a chain transfer agent such as carbon tetrachloride.

[0077] The polymerizable composition may contain a crosslinking agent as needed. The polymerizable composition may also contain a solvent. Furthermore, the polymerizable composition does not have to contain maleic anhydride, and the molar ratio of maleic anhydride to monomer (A) is 5 / 95 or less, more preferably 3 / 97 or less, and even more preferably 1 / 99 or less.

[0078] (Second embodiment) The polymer according to the second embodiment of the present invention contains a structural unit (A) represented by the following formula (A), and the molar ratio of structural unit (C) represented by the following formula (C) to structural unit (A) in the polymer is 5 / 95 or less. Such a polymer exhibits excellent dielectric strength on the oxidation side. [ka] (In formula (A), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, M is an alkali metal element selected from Li, Na, and K, and * indicates the position where structural unit (A) bonds with other structural units.) [ka]

[0079] The polymer according to the second embodiment may be a copolymer containing structural unit (A) and structural units other than structural unit (A) as structural units. The copolymer may contain structural unit (A) as the main component. The polymer may not contain structural unit (C), and the molar ratio of structural unit (C) to structural unit (A) is 5 / 95 or less, more preferably 3 / 97 or less, and even more preferably 1 / 99 or less. When the content of structural unit (C) in the polymer is within this range, the oxidative stability of the polymer tends to be high.

[0080] The ratio m of structural unit (A) to the total structural units contained in the polymer may be 0.2 to 0.95, and may be 0.2 to 0.8, and is preferably 0.3 to 0.7, and more preferably 0.4 to 0.6. n is preferably 0.3 to 0.7, and more preferably 0.4 to 0.6.

[0081] A preferred example of structural unit (A) may be the structural unit (A) in the polymer of the first embodiment.

[0082] The polymer of this embodiment may contain structural units other than structural unit (A). Preferably, such structural units are those obtained by radical polymerization of monomers having ethylenically unsaturated groups, and may be the second structural unit in the polymer of the first embodiment, and may be at least one of structural unit (B1) and structural unit (B2). The types of structural units (B1) and structural unit (B2), and the range of their content, can be the same as in the first embodiment. Furthermore, the polymer according to this embodiment may contain structural units derived from a crosslinking agent, including structural units produced by the reaction of structural unit (A) with one or two molecules of water, or structural units produced by the hydrolysis of structural unit (C). The molar ratio of structural units derived from the maleic anhydride derivative to the first structural unit may be 5 / 95 or less. Structural units derived from maleic anhydride are structural units having a chemical structure directly obtained when a maleic anhydride derivative is radically polymerized.

[0083] The polymer production method of this embodiment preferably includes a step of polymerizing a monomer (monomer mixture) containing the monomer (A') represented by formula (A'). Such a polymer production method is suitable for producing the polymer of this embodiment. The polymerization of the monomer may be carried out in a polymerizable composition containing an initiator.

[0084] The polymers of the first and second embodiments tend to have high ionic conductivity (alkali metal ion conductivity), and therefore may be included in batteries as ionic conductive materials. The polymers of these embodiments can be used, for example, as electrolytes in batteries such as lithium-ion batteries, sodium-ion batteries, and potassium-ion batteries, as well as as electrolytes in capacitors. The oxidation potential of the polymers of the first and second embodiments is Li / Li + The voltage is preferably 4.5V or higher with respect to the electrode, more preferably 4.6V or higher, and particularly preferably 4.8V or higher.

[0085] The polymers of the first and second embodiments may be mixed with a plasticizer to form an electrolyte composition for use as an electrolyte in a battery, etc. That is, the electrolyte composition of this embodiment may contain the polymer of the first or second embodiment and may further contain a plasticizer. The plasticizer may be an organic solvent or an aprotic solvent. The organic solvent may be at least one selected from the group consisting of carbonate solvents, fluorine solvents, and ether solvents, and these solvents may be aprotic solvents. The use of a plasticizer tends to make the electrolyte composition easier to mold.

[0086] Examples of carbonate-based solvents include linear carbonates such as dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate; and cyclic carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate, and vinylene carbonate. Examples of ether-based solvents include cyclic ethers such as tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, and 1,3-dioxolane; and linear ethers such as 1,2-diethoxyethane and ethoxymethoxyethane. Examples of fluorine-based solvents include hydrofluorocarbons such as perfluorooctane; hydrofluoroethers such as methyl nonafluorobutyl ether and ethyl nonafluorobutyl ether; and hydrofluoroolefins such as 1,3,3,3-tetrafluoropropene. In addition, aprotic solvents such as dimethyl sulfoxide (DMSO), dimethylformamide (DMF), and dimethylacetamide (DMA) are also used.

[0087] The amount of plasticizer in the electrolyte composition may be 20 to 500 parts by mass, 50 to 300 parts by mass, or 100 to 250 parts by mass per 100 parts by mass of the polymer.

[0088] The electrolyte composition may further contain other resins. Examples of other resins include fluororesins. Preferred fluororesins are those having carbon chains as their main chain. The carbon chains may be formed by radical polymerization of ethylenically unsaturated groups. Examples of fluororesins include poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and polyvinylidene fluoride (PVDF).

[0089] The electrolyte composition may contain a lithium salt in addition to the polymer mentioned above. The lithium salt is not particularly limited, but may include LiCl, LiBr, LiI, LiClO4, LiPF6, LiBF4, Li2SO4, Li[(C h F 2h+1 Examples include SO2[2N(h is 0-3)). [Examples]

[0090] <Polymer manufacturing> The following monomers A1, B1, B2, B3, and B4 were prepared.

[0091] (Synthesis of monomer A1) Under a nitrogen atmosphere, trifluoromethanesulfonamide (52.5 mmol, 7.83 g, manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in dehydrated acetonitrile (150 mL, manufactured by Kanto Chemical Co., Ltd.). To this solution, lithium hydroxide (105 mmol, 2.51 g, manufactured by Tokyo Chemical Industry Co., Ltd.) and 4-acetamidobenzenesulfonyl chloride (50 mmol, 11.68 g, manufactured by Tokyo Chemical Industry Co., Ltd.) were added sequentially and the mixture was heated under reflux for 5 hours. After cooling to room temperature, an excess amount of acetonitrile (700 mL) was added to precipitate the solid, which was separated by filtration and washed with dichloromethane (manufactured by Kanto Chemical Co., Ltd.) to obtain intermediate 1. The yield was 97.1%. • Structural formula of intermediate 1: [ka]

[0092] Under a nitrogen atmosphere, 5% hydrochloric acid (22.5 mL) was added to intermediate 1 (15 mmol, 5.28 g) and stirred at 90°C for 2 hours. After cooling to room temperature, lithium hydroxide aqueous solution was added until the pH reached 7 or higher, as confirmed by pH test paper, and then a solid was obtained by vacuum drying. The obtained solid was extracted with acetonitrile solution and vacuum drying was obtained to obtain intermediate 2. The yield was 92.6% based on the raw materials of intermediate 1. • Structural formula of intermediate 2: [ka]

[0093] Under a nitrogen atmosphere, maleic anhydride (13.3 mmol, 1.30 g, manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in dehydrated 1,4-dioxane (manufactured by Kanto Chemical Co., Ltd.). To this solution, the entire volume of a solution of intermediate 2 (13.2 mmol, 4.09 g) prepared under a nitrogen atmosphere in dehydrated tetrahydrofuran (26.4 mL, manufactured by Kanto Chemical Co., Ltd.) was added dropwise, and the mixture was stirred at room temperature for 12 hours. After the reaction, the precipitate was filtered and vacuum-dried at 60°C for 4 hours to obtain a solid containing intermediate 3. • Structural formula of intermediate 3: [ka]

[0094] Under a nitrogen atmosphere, a solid containing intermediate 3 (14.0 mmol, 5.70 g) and an aqueous sodium acetate solution (13.3 mmol, 1.09 g, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to acetic anhydride (12.3 mL, manufactured by Tokyo Chemical Industry Co., Ltd.), and the mixture was stirred at 70°C for 3 hours. The reaction solution was then added dropwise to an excess amount of diethyl ether (manufactured by Kanto Chemical Co., Ltd.) at 0°C, and the precipitate was collected by filtration. Under an inert atmosphere, the precipitate was extracted with dehydrated acetonitrile (manufactured by Kanto Chemical Co., Ltd.), and A1 was obtained by drying under reduced pressure. The yield throughout the entire process was 72.8%. • Monomer A1: The following compound (A1) [ka]

[0095] B1: A commercially available reagent manufactured by Tokyo Chemical Industry Co., Ltd., with a purity of >99%, was washed with 10% NaOHaq. and pure water, sealed with KOH, dried overnight, and then purified by atmospheric distillation with CaH2 to improve its purity. B2: A commercially available reagent from Aldrich with a purity of >98% was sealed with CaCl2 and dried overnight. The purity was then improved by adding CaH2 and performing vacuum distillation. B3: Commercial reagents from Aldrich with a purity of >98% were used as is. B4: A commercially available reagent from Aldrich with a purity of >98% was sealed with CaCl2 and dried overnight. The purity was then improved by adding CaH2 and performing vacuum distillation.

[0096] Monomer B1: Isobutyl vinyl ether Monomer B2: n-dodecyl vinyl ether Monomer B3: Tetraethylene glycol methyl vinyl ether Monomer B4: Styrene

[0097] (Example A1) Monomer A1:0.741g, monomer B1:0.340g, and azobisisobutyronitrile (AIBN):8.2mg were dissolved in 10mL of anhydrous acetonitrile. Tetralin was added as an internal standard, and the reaction was carried out at 60°C for 24 hours under a nitrogen atmosphere while monitoring the monomer consumption rate. The polymerization solution was dialyzed in acetonitrile and vacuum-dried at 120°C to obtain copolymer 1, 0.34g (yield 82%). The monomer introduction ratio was A1:B1 = 62:38. 1 The calculation was performed using 1H-NMR. Copolymer 1 has a number-average molecular weight Mn = 1.7 × 10⁻⁶ 4 , weight average molecular weight Mw=2.9×10 4 The molecular weight distribution was Mw / Mn = 1.70.

[0098] (Example A2) Monomer A1:0.936g, monomer B2:1.53g, and AIBN:16.4mg were dissolved in 20mL of dehydrated acetonitrile. Tetralin was added as an internal standard, and the reaction was carried out at 60°C for 24 hours under a nitrogen atmosphere while monitoring the monomer consumption rate. The polymerization solution was dialyzed in acetonitrile and vacuum-dried at 120°C to obtain 0.637g of copolymer 2 (yield 44%). The monomer introduction ratio was A1:B2 = 55:45. 1 The calculation was performed using 1H-NMR. Copolymer 2 has a number-average molecular weight Mn = 4.9 × 10⁻⁶ 4 , weight average molecular weight Mw=7.9×10 4 The molecular weight distribution was Mw / Mn = 1.63.

[0099] (Example A3) Monomer A1:1.17g, monomer B3:2.25g, and AIBN:24.6mg were dissolved in 30mL of dehydrated acetonitrile. Tetralin was added as an internal standard, and the reaction was carried out at 60°C for 24 hours under a nitrogen atmosphere while monitoring the monomer consumption rate. The polymerization solution was dialyzed in acetonitrile and vacuum-dried at 120°C to obtain 1.49g of copolymer 3 (yield 79%). The monomer introduction ratio was A1:B3 = 41:59. 1 The calculation was performed using 1H-NMR. Copolymer 3 has a number-average molecular weight Mn = 1.4 × 10⁻⁶. 4 , weight average molecular weight Mw=2.7×10 4 The molecular weight distribution was Mw / Mn = 1.85.

[0100] (Example A4) Monomer A1:0.558g, monomer B4:0.149g, and AIBN:11.7mg were dissolved in 13.4mL of anhydrous acetonitrile. Tetralin was added as an internal standard, and the reaction was carried out at 60°C for 24 hours under a nitrogen atmosphere while monitoring the monomer consumption rate. The polymerization solution was dialyzed in acetonitrile and vacuum-dried at 120°C to obtain 0.640g of copolymer 4 (yield 87%). The monomer introduction ratio was A1:B4 = 52:48. 1 The calculation was performed using 1H-NMR. Copolymer 4 has a number-average molecular weight Mn = 8.7 × 10⁻⁶. 4 , weight average molecular weight Mw=2.2×10 5 The molecular weight distribution was Mw / Mn = 2.55.

[0101] (Comparative Example A1) Poly(ethylene-alt-maleic anhydride) (weight-average molecular weight = 100,000-500,000, product number: 188050) manufactured by Aldrich was used as copolymer 5.

[0102] <Measurement of Oxidation Potential of Copolymers> The oxidation potential of each copolymer in Examples A1 to A4 and Comparative Example A1 was measured as follows. A polymer solution was prepared by dissolving the copolymer in a 1 M LiClO4 propylene carbonate solution in a nitrogen-purged glove box. The copolymer concentration in the polymer solution was 10 mM in terms of lithium ions. At room temperature (25°C), the polymer solution was injected into a triode cell (manufactured by EC Frontier) inside the glove box, and linear sweep voltameometry (sweep speed: 5 mV / s, sweep range: from open-circuit potential to Li / Li) was performed under an argon atmosphere using a measuring device (HZ7000 electrochemical measurement system, manufactured by Hokuto Denko Co., Ltd.). + (Based on +5.5V, working electrode: platinum wire, counter electrode: lithium, reference electrode: lithium), 20 μA / cm² 2 The oxidation potential was defined as the potential at which the current density was observed. The results are shown in Table 1.

[0103] [Table 1]

[0104] (Example B1) An electrolyte composition was obtained by adding 200 parts by mass of a plasticizer to 100 parts by mass of copolymer 1. A mixed solvent of ethylene carbonate and propylene carbonate (volume ratio 1:1) was used as the plasticizer. The following measurements were performed on the obtained electrolyte composition. The results are shown in Table 2.

[0105] Ionic conductivity: An evaluation cell for a CR2032 coin cell was assembled inside a glove box under a dry argon atmosphere. Specifically, a test laminate was created by stacking the following layers within the evaluation cell: (stainless steel plate / electrolyte composition / stainless steel plate). The impedance is measured using an impedance measuring device under the following conditions: 25°C, frequency range 0.1Hz to 1MHz, and applied voltage 10mV (vs. open-circuit voltage). The ionic conductivity σ can be calculated using the following formula. σ(S·cm -1 ) = t(cm) / (R(Ω) × A(cm) 2 )) In the formula, R represents the impedance value, A represents the sample area, and t represents the sample thickness.

[0106] Activation energy: Ionic conductivity measurements using the evaluation cell described above were also performed under conditions of 30, 40, 50, 60, and 70°C to measure the change in ionic conductivity with respect to temperature. The activation energy was calculated from the slope of the graph of the common logarithm of ionic conductivity and the reciprocal of temperature using the Arrhenius equation (logk = logA - Ea / RTk: reaction rate constant, A: frequency factor, Ea: activation energy, R: gas constant, T: absolute temperature).

[0107] Lithium ion transport rate: An evaluation cell for a CR2032 coin-type lithium battery was assembled in a glove box under a dry argon atmosphere. Specifically, a test laminate was created by stacking the following layers within the evaluation cell: (Lithium / Electrolyte composition / Lithium) The lithium-ion transport fraction measurement method is described in Polymer, 28, 2324 (1987). Specifically, at room temperature (25°C), 10mV is applied to the test laminate, and the initial current value (I0) and steady-state current value (I0) are measured. ss ) is measured, and further, the interface resistance measurement R0 before voltage application and the interface resistance measurement R after voltage application are measured. SS The values ​​were determined by the complex impedance method. Then, the lithium ion transport fraction (t) was calculated by substituting the obtained values ​​into the following equation. Li+ The formula was calculated as follows: V in the formula is the applied voltage. t Li+ =I ss (V-I0R0) / I0(VI SS R SS )

[0108] (Example B2) An electrolyte composition was obtained in the same manner as in Example B1, except that copolymer 2 was used instead of copolymer 1. Various measurements were performed on the obtained electrolyte composition in the same manner as in Example B1. The results are shown in Table 2.

[0109] (Example B3) An electrolyte composition was obtained in the same manner as in Example B1, except that copolymer 3 was used instead of copolymer 1. Various measurements were performed on the obtained electrolyte composition in the same manner as in Example B1. The results are shown in Table 2.

[0110] (Example B4) An electrolyte composition was obtained in the same manner as in Example B1, except that copolymer 4 was used instead of copolymer 1. Various measurements were performed on the obtained electrolyte composition in the same manner as in Example B1. The results are shown in Table 2.

[0111] (Example B5) A composite resin was prepared by mixing 100 parts by mass of copolymer 1 with 100 parts by mass of poly(vinylidene fluoride-co-hexafluoropropylene). The same plasticizer as in Example B1 was added to the composite resin at a ratio of 200 parts by mass per 100 parts by mass of polymer 1 to obtain an electrolyte composition. Various measurements were performed on the obtained electrolyte composition in the same manner as in Example B1. The results are shown in Table 2.

[0112] [Table 2]

Claims

1. A polymer comprising a first structural unit which is at least one structural unit (A) represented by the following formula (A), and a second structural unit which is at least one structural unit (B1) represented by the following formula (B1) and a structural unit (B2) represented by the following formula (B2): A polymer (excluding a BA-type diblock copolymer or a BAB-type triblock copolymer) that satisfies at least one of the following conditions (1) and (2) and at least one of the following conditions (3) and (4): (1) The ratio m of the first structural units to all structural units contained in the polymer is 0.2 to 0.8, and the ratio n of the second structural units to all structural units contained in the polymer is 0.2 to 0.

8. (2) The content of the first structural unit is 25 to 95% by mass, and the content of the second structural unit is 5 to 75% by mass, based on the total mass of the polymer. (3) The number average molecular weight (Mn) of the polymer is 5,000 to 200,000. (4) The weight average molecular weight (Mw) of the polymer is 5,000 to 300,000. 【Chemistry 1】 (In formula (A), X is a divalent organic group having 1 to 20 carbon atoms, Y is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, M is an alkali metal element selected from Li, Na, and K, and * represents the position at which the structural unit (A) is bonded to another structural unit.) 【Chemistry 2】 (In formula (B1), R １ ~R ４ are each independently a hydrogen atom, a halogen atom, or a monovalent organic group having 1 to 20 carbon atoms. * represents the position at which the structural unit (B1) is bonded to another structural unit. 【Transformation 3】 (In formula (B2), R １５ is a divalent organic group having 1 to 20 carbon atoms, and R １６ and R １７ are each a hydrogen atom, a halogen atom, or a monovalent organic group having 1 to 20 carbon atoms. １５ is -C(=O)-O-C(=O)- and R １６ and R １７ In this case, the structural unit (A) does not include a structural unit in which both of the above are hydrogen atoms, and a structural unit contained in the structural unit (A).

2. The polymer according to claim 1, wherein the molar ratio of the structural unit (C) represented by the following formula (C) to the first structural unit in the polymer is 5 / 95 or less: 【Chemistry 4】

3. The oxidation potential is Li / Li ＋ The polymer according to claim 1 or 2, which has a voltage of 4.5 V or more relative to the electrode.

4. The polymer according to any one of claims 1 to 3, wherein the second structural unit comprises a structural unit (D) represented by the following formula (D): 【Transformation 5】 (Z is a covalent bond, —O—, —S—, —C(═O)—, or —C(═O)O—; R ２２ is a hydrogen atom or a monovalent hydrocarbon group, and R ２１ is a monovalent organic group. * represents the position where the structural unit (D) is bonded to another structural unit.

5. The polymer according to any one of claims 1 to 4, wherein the molar ratio of the structural unit (A) to the total number of moles of the structural unit (A) and the structural unit (B1) is greater than 0.

40.

6. An electrolyte composition comprising the polymer according to any one of claims 1 to 5.

7. An electrolyte composition comprising the polymer according to any one of claims 1 to 5.

8. The electrolyte composition of claim 6 further comprising a plasticizer.

9. The electrolyte composition of claim 8 , wherein the plasticizer is an organic solvent.

10. A battery comprising the polymer according to any one of claims 1 to 5 or the electrolyte composition according to any one of claims 6 to 9.

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