JP5481229B2 - Reticulated polymer and gel electrolyte using the same - Google Patents

Description

  The present invention crosslinks a multi-branched polymer having a core part having three or more branched chains and an arm part bonded to the branched chain of the core part and containing a repeating unit derived from a polymerizable unsaturated bond. The present invention relates to a network polymer which is a reaction product of an agent and a gel electrolyte using the same.

  Gel-like polymer electrolytes are used in secondary batteries, particularly lithium secondary batteries, used as power sources for portable electronic devices such as mobile phones and personal computers. As for the polymer used in the gel-like polymer electrolyte, a polyether-based (for example, Non-Patent Document 1) polymer, a polymethyl methacrylate-based (for example, Non-Patent Documents 2 and 3), and a polyfluorinated polymer electrolyte are used. Vinylidene (for example, Non-Patent Document 4, Patent Document 1), polyacrylonitrile (for example, Non-Patent Document 5), polyurethane (for example, Non-Patent Documents 6 and 7), epoxy-based polymer, polysulfone (for example, patent) Various substances such as literature 2) have been studied.

  These conventional gel electrolytes are prepared by mixing electrolyte solution, monomer, bifunctional monomer and initiator and gelling by thermal polymerization (chemically crosslinked gel), or by absorbing electrolyte solution in polymer matrix The supporting method (physically cross-linked gel) was common.

The former chemically cross-linked gel is described in, for example, Patent Document 3, and is characterized by excellent electrolyte solution retention, but radicals generated during polymerization are consumed by the graphite of the negative electrode and are not reacted. There was a risk that the monomer would remain. The unreacted site reacted due to the oxidation / reduction of the positive electrode active material, causing a decrease in long-term reliability of the battery. Moreover, the mechanical strength of the obtained gel electrolyte was low, and there was a risk of short circuit.
Further, in the case of the latter physical cross-linking gel, for example, as described in Patent Document 4, since a gel is formed by injecting and heating an electrolytic solution after forming a battery element, conventional liquid electrolysis is performed. There is an advantage that a battery manufacturing method using a liquid can be applied. However, since the gel is liquefied at a high temperature, there is a risk of liquid leakage at a high temperature or abnormal reaction.

  On the other hand, the present inventors have developed a star polymer (multi-branched polymer) that can be used as a polymer solid electrolyte (Patent Document 5). However, since there has been no example of using a star polymer as a gel electrolyte in the past, this is used as a gel electrolyte. However, it was unsuitable as a gel electrolyte.

  On the other hand, the present inventors have developed a star polymer (multi-branched polymer) that can be used for a polymer solid electrolyte (Patent Document 1). However, since no star polymer has been conventionally used for a gel electrolyte, this is used as a gel electrolyte. However, it was unsuitable as a gel electrolyte.

JP 2004-356102 A JP 2003-045490 A JP 2009-15896A JP-T 8-507407 International Publication WO2006 / 016665 Pamphlet

M. Kono, E Hayashi, M. Nishiura, and M. Watanabe, Journal of The Electrochemical Society, 147 (7) 2517-2524 (2000). P.E.Stallworth, S.G.Greenbaum, F.Croce, S.Slane, and M. Salomon, Electrochimica Acta, 40 (13-14) 2137-2141 (1995). S. Kuwabata and M. Tomiyori, Journal of The Electrochemical Society, 149 (8) A988-A994 (2002) T. Michot, A. Nishimoto, and M. Watanabe, Electrochimica Acta, 451347-1360 (2000). H. Akashi, K. Tanaka, and K. Sekai, Journal of The Electrochemical Society, 145 (3) 881-887 (1998) M.L.Digar, S.L.Hung, T.C.Wen, and A. Gopalan, Polymer 431615-1622 (2002). H.L.Wang, H.M.Kao, M. Digar, and T.C. Wen, Macromolecules 34 (3) 529-537 (2001).

  The present invention has been made in view of such a state of the art, and an object of the present invention is to provide a polymer that does not have any unreacted monomer and that can be used as a polymer gel electrolyte that supports an electrolytic solution. .

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a network polymer obtained by reacting a multibranched polymer described in International Publication WO2006 / 016665 pamphlet with PEO as a crosslinking agent leaves unreacted monomers. However, the present inventors found it suitable as a gel electrolyte and completed the present invention.

That is, the present invention provides (1) the following formula: X [BY (A) _n1 ] _n2
Wherein A is the formula (I)

(Wherein R ¹ , R ² and R ³ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ¹ and R ³ may combine to form a ring. R ^4a and R ^4b each independently represent a hydrogen atom or a methyl group, and R ⁵ represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, an acyl group having 1 to 10 carbon atoms, or 3 to 3 carbon atoms. 20 represents a tri-substituted silyl group, m represents an integer of 1 to 100, and when m is 2 or more, R ^4a and R ^4b may be the same or different. A repeating unit represented by formula (II)

(Wherein, ^{R 6} and ^{R 8} each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, ^{R 6} and ^{R 8} may form a ring, ^{R 7} Is a hydrogen atom; a hydrocarbon group having 1 to 10 carbon atoms; a hydroxyl group; a hydrocarbon oxy group having 1 to 10 carbon atoms; a carboxyl group; an acid anhydride group; an amino group; an ester group; or a hydroxyl group, a carboxyl group, and an epoxy. Represents an organic group having at least one functional group selected from the group consisting of a group, an acid anhydride group, and an amino group, and R ⁹ consists of a hydroxyl group, a carboxyl group, an epoxy group, an acid anhydride group, and an amino group Represents an organic group having at least one functional group selected from the group.) Represents a random copolymer comprising a repeating unit represented by:
B is the formula (III)

(Wherein R ¹⁰ , R ¹¹ and R ¹² each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ¹³ represents an aryl group or a heteroaryl group). A polymer containing repeating units is represented.
X represents an organic group having three or more bonds with B, and Y represents a functional group having a structure capable of having an active halogen atom.
n1 represents 1 or 2, and n2 represents any integer of 2 to 16. )
A network polymer obtained by reacting a multi-branched polymer represented by
(2) The multi-branched polymer represented by the following formula: X [BY (A) _n1 ] _n2 is represented by the formula (VIII)

(In the formula, Z represents (CH ₂ ) q or a p-phenylene group, q represents an integer of 0 to 3, and each R independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, An aryl group which may have a substituent, a halogen atom, or an alkoxyl group having 1 to 6 carbon atoms, each n3 independently represents an integer of 0 to 3, and each n4 represents Independently represents an integer of 1 to 3.
A, B, Y and n1 are the same as defined in the above (1), and each A, B, Y and n1 may be the same or different. )
It is related with the network polymer as described in said (1) which is a compound represented by these.

The present invention also provides:
(3) A polymer gel electrolyte comprising the network polymer according to (1) or (2) and an electrolytic solution.

The network polymer of the present invention does not contain the monomer used in the synthesis, and can be handled as a free-standing film when formed into a sheet. Further, the network polymer of the present invention is suitable as a gel electrolyte, and the gel electrolyte prepared by sucking an electrolytic solution after sheet processing can be handled as a self-supporting film, and has a prospect for practical use.
The network polymer of the present invention is suitable as a resist material; an electrochemical material such as a battery, a capacitor, a sensor, a capacitor, an EC element, and a photoelectric conversion element; an inclusion material; a functional material such as an electrical appliance or industrial equipment. is there.

It is a figure which shows the ionic conductivity of the polymer gel electrolyte membrane by a temperature change.

Hereinafter, the present invention will be described in detail.
1 network polymer The network polymer of this invention is a polymer which has a three-dimensional structure obtained by reaction of the hyperbranched polymer shown below and a crosslinking agent. The weight average molecular weight by GPC-MALLS (gel permeation chromatography multi-angle light scattering detection method) is 10,000 to 2,000,000. Further, the molecular weight distribution (Mw / Mn) is usually 1.05 to 2, preferably 1.1 to 1.5.

  The hyperbranched polymer has a functional group capable of reacting with about 10 to 200 crosslinkers per molecule, and the blending ratio of the multibranched polymer and the crosslinker depends on the reactive functionality in the multibranched polymer. The equivalent ratio of the reactive functional group in the crosslinking agent to the group is 1: 0.5 to 2, preferably 1: 0.8 to 2.

[Multi-branched polymer]
The multibranched polymer of the present invention has a structure represented by the following formula.
Formula: X [B-Y (A) _n1 ] _n2
Below, each part in the said Formula is demonstrated.

(X)
In the above formula, X represents an organic group having 3 or more bonds.
As a specific example of X,
(I) a carbon atom having 4 branched chains, a carbon atom having 4 branched chains, and an alkylene group, alkenylene group, alkynylene group, phenylene group, or a combination of two or more of these groups, etc. Organic groups centered on
(Ii) carbon atoms having three branched chains, carbon atoms having three branched chains, and an alkylene group, alkenylene group, alkynylene group, phenylene group, or a combination of two or more of these groups, etc. Organic groups centered on
(Iii) Nitrogen atoms such as a nitrogen atom having three branched chains, a nitrogen atom having three branched chains and an alkylene group, an alkenylene group, an alkynylene group, a phenylene group or a combination of two or more thereof. Organic groups centered on
(Iv) a phenyl group having 3 or more branched chains, a phenyl group having 3 or more branched chains and an alkylene group, an alkenylene group, an alkynylene group, a phenylene group, or a combination of two or more of these groups, etc. And an organic group having a benzene ring as the center.

  In addition, the above (alkylene group, alkenylene group, alkynylene group, phenylene group or two or more groups thereof) is —O—, —S—, —C (═O) —, —C (═O) O—. , —NH—, —NHC (═O) —, —NHC (═S) —, —OC (═O) NH—, which may further have one or more groups at any position. Good.

(A)
In the above formula, A represents an arm portion composed of a random copolymer having a repeating unit derived from a monomer having a polymerizable unsaturated bond, and a plurality of A may be the same or different.
In addition, each A has a functional group capable of binding to a crosslinking agent.

  The random copolymer of A has the formula (I)

A repeating unit represented by formula (II)

It has a repeating unit represented by
In addition to the above-described repeating units, A may have other repeating units that can be copolymerized therewith.
Examples of such polymerizable monomers that give other copolymerizable repeating units include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene. Conjugated dienes such as 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,6-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene Α, β-unsaturated carboxylic imides such as N-methylmaleimide and N-phenylmaleimide; α, β-unsaturated nitriles such as (meth) acrylonitrile; and the like.

R ^{1 to} R ⁵ and m in the repeating unit (I) are as follows.
R ^{1 to} R ³ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.
Here, as a C1-C10 hydrocarbon group, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, an arylalkyl group etc. are represented, for example, a methyl group, an ethyl group, etc. Alkyl groups such as n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group, t-butyl group, n-hexyl group, n-octyl group and n-decyl group; vinyl group, 1 -Alkenyl groups such as propenyl group, 2-propenyl group, 1-butenyl group, 2-butenyl group, 1-pentenyl group, 2-pentenyl group, 1-hexenyl group and 2-hexenyl group; ethynyl group, 1-propynyl group 2-propynyl group, 1-butynyl group, 2-butynyl group, 1-pentynyl group, 2-pentynyl group, 1-hexynyl group, 2-hexynyl group, 1-heptyl Alkynyl groups such as 1-octynyl group, 1-decynyl group; cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, phenyl group, naphthyl group Aryl groups such as groups; arylalkyl groups such as benzyl groups and phenethyl groups.
R ¹ and R ³ may combine to form a ring.

R ^4a and R ^4b each independently represent a hydrogen atom or a methyl group.
R ⁵ represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, an acyl group having 1 to 10 carbon atoms, or a tri-substituted silyl group having 3 to 20 carbon atoms.
Examples of the hydrocarbon group having 1 to 10 carbon atoms can be exemplified the same groups as above ^R 1 to R ^3.
Examples of the acyl group having 1 to 10 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, pentanoyl group, hexanoyl group, heptanoyl group, octanoyl group and the like, and a trisubstituted silyl group having 3 to 20 carbon atoms. Examples thereof include a trimethylsilyl group, a t-butyldimethylsilyl group, and a dimethylphenylsilyl group.

Further, the hydrocarbon group of R ¹ to R ⁵ may have a substituent on an appropriate carbon atom. Specific examples of such substituents include halogen atoms such as fluorine atom, chlorine atom and bromine atom; hydrocarbon groups such as methyl group, ethyl group, n-propyl group, phenyl group, naphthyl group and benzyl group; acetyl group, Cyano group; nitro group; hydrocarbon oxy group such as methoxy group and phenoxy group; alkylthio group such as methylthio group; alkylsulfinyl group such as methylsulfinyl group; alkylsulfonyl group such as methylsulfonyl group; An amino group which may be substituted such as an amino group and a dimethylamino group; an anilino group and the like may be mentioned.

m represents an integer of 1 to 100, and is preferably an integer of 2 to 50. Moreover, the value of m in each repeating unit may be the same or different.
When m is 2 or more, R ^4a and R ^4b may be the same or different.
The degree of polymerization of the repeating unit (I) is preferably 5 or more, more preferably 10 or more, although it depends on the value of m.

  Specific examples of the monomer giving the repeating unit (I) include the following.

2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-methoxypropyl (meth) acrylate, 2-ethoxypropyl (meth) acrylate, methoxypolyethylene glycol (the number of units of ethylene glycol is 2 to 100) (Meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (propylene glycol has 2 to 100 units) (meth) acrylate, ethoxypolypropylene glycol (meth) acrylate, phenoxypolypropylene Glycol (meth) acrylate, polyethylene glycol mono (meth) acrylate, 2-hydroxypropyl (meth) acrylate, poly Propylene glycol mono (meth) acrylate, polyethylene glycol-polypropylene glycol mono (meth) acrylate, octoxy polyethylene glycol-polypropylene glycol mono (meth) acrylate, lauroxy polyethylene glycol mono (meth) acrylate, stearoxy polyethylene glycol mono (meth) Acrylate, “Blemmer PME series” [monomer corresponding to R ¹ = R ² = hydrogen atom, R ³ = methyl group, m = 2 to 90 in formula (I)] (manufactured by NOF Corporation), acetyl Oxypolyethylene glycol (meth) acrylate, benzoyloxypolyethylene glycol (meth) acrylate, trimethylsilyloxypolyethylene glycol (meth) acrylate, t-butyldimethyl Silyloxy polyethylene glycol (meth) acrylate, methoxy polyethylene glycol cyclohexene-1-carboxylate, methoxy polyethylene glycol - cinnamate.
These compounds can be used alone or in combination of two or more.

R ^{6 to} R ⁹ in the repeating unit (II) are as follows.
R ⁶ and R ⁸ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.
Here, the C1-C10 hydrocarbon group can illustrate the group similar to R < ¹ > -R < ³ > of said formula (I).
R ⁶ and R ⁸ may combine to form a ring.

R ⁷ is a hydrogen atom; a hydrocarbon group having 1 to 10 carbon atoms; a hydroxyl group; a hydrocarbon oxy group having 1 to 10 carbon atoms; a carboxyl group; an acid anhydride group; an amino group; an ester group; or a hydroxyl group or a carboxyl group. , An organic group having at least one functional group selected from the group consisting of an epoxy group, an acid anhydride group, and an amino group.
Here, the C1-C10 hydrocarbon group can illustrate the group similar to R < ¹ > -R < ³ > of said formula (I). The hydrocarbon oxy group having 1 to 10 carbon atoms is a group in which a hydrocarbon group having 1 to 10 carbon atoms and an oxygen atom are bonded, and the hydrocarbon group having 1 to 10 carbon atoms is represented by the formula (I). The same group as R < ¹ > -R < ³ > can be illustrated.
Here, the organic group is a hydrocarbon group; a hydrocarbon group bonded to —O—, —CO— or —COO—; an oxygenated heterocyclic group, and the hydrocarbon group or heterocyclic group is preferably And having 1 to 10 carbon atoms. Examples of the hydrocarbon group include an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, and an arylalkyl group. Specific examples of these groups include the same groups as R ^{1 to} R ^{3 in} the above formula (I).

R ⁹ represents an organic group having at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, an epoxy group, an acid anhydride group, and an amino group.
In R ⁷ and R ⁹ , the hydroxyl group, carboxyl group, epoxy group, acid anhydride group, and amino group are functional groups for bonding with the crosslinking agent.
Examples of these functional groups or organic groups having these functional groups include the following.

  The following compounds can be illustrated as a raw material monomer which produces | generates the repeating unit which has such a functional group.

  Said compound can be used individually by 1 type or in combination of 2 or more types.

R ^{6 to} R ⁹ may have a substituent on an appropriate carbon atom. Specific examples of such substituents include halogen atoms such as fluorine atom, chlorine atom and bromine atom; hydrocarbon groups such as methyl group, ethyl group, n-propyl group, phenyl group, naphthyl group and benzyl group; acetyl group, Cyano group; nitro group; hydrocarbon oxy group such as methoxy group and phenoxy group; alkylthio group such as methylthio group; alkylsulfinyl group such as methylsulfinyl group; alkylsulfonyl group such as methylsulfonyl group; And an amino group which may be substituted such as an amino group and a dimethylamino group; an anilino group; and the like.

The degree of polymerization of the repeating units (I) and (II) in the random copolymer is preferably 30 to 2000, and particularly preferably 50 to 1000.
The proportion of the repeating unit (I) in the random copolymer is preferably in the range of 30 to 60% by weight, and the proportion of the repeating unit (II) is in the range of 40 to 70% by weight. preferable.
In the repeating unit (I), the repeating unit portion represented by the following formula (IV) is preferably 30 to 60% by weight.

(In the formula, R ^4a and R ^4b each independently represent a hydrogen atom or a methyl group.)

(B)
B is the formula (III)

The polymer containing the repeating unit represented by these is represented.
In the formula, R ¹⁰ , R ¹¹ and R ¹² each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ¹³ represents an aryl group or a heteroaryl group.
Here, the hydrocarbon group having 1 to 10 carbon atoms in R ¹⁰ , R ¹¹ and R ¹² represents an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, an arylalkyl group or the like, specifically Is, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group, t-butyl group, n-hexyl group, n-octyl group, n-decyl group Alkyl groups such as vinyl group, 1-propenyl group, 2-propenyl group, 1-butenyl group, 2-butenyl group, 1-pentenyl group, 2-pentenyl group, 1-hexenyl group, 2-hexenyl group and the like Group: ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 1-pentynyl group, 2-pentynyl group, 1-hexini Alkynyl groups such as thiol group, 2-hexynyl group, 1-heptynyl group, 1-octynyl group, 1-decynyl group, etc .; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group Aryl groups such as cycloalkyl groups such as phenyl group and naphthyl group; arylalkyl groups such as benzyl group and phenethyl group.
Examples of the aryl group for R ¹³ include a phenyl group, a naphthyl group, an azulenyl group, an indenyl group, an indanyl group, and a tetralinyl group. Of these, an aryl group having 6 to 10 carbon atoms is preferable.
Examples of the heteroaryl group for R ¹³ include pyridinyl, imidazolyl, pyrimidinyl, pyrazolyl, triazolyl, pyrazinyl, tetrazolyl, furyl, thienyl, isoxazolyl, thiazolyl, oxazolyl, isothiazolyl, pyrrolyl, quinolinyl, isoquinolinyl, indolyl, benzimidazolyl, Benzofuranyl, cinnolinyl, indazolyl, indolizinyl, phthalazinyl, pyridazinyl, triazinyl, isoindolyl, pteridinyl, purinyl, oxadiazolyl, triazolyl, thiadiazolyl, thiadiazolyl, furazanyl, benzofurazanyl, benzothiophenyl, benzothiazolyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl Can be mentioned.
The degree of polymerization of the repeating unit (III) in the polymer is preferably 10 to 500, and particularly preferably 50 to 200.
The B may have a repeating unit derived from another polymerizable monomer in addition to the repeating unit described above.

  Examples of such other polymerizable monomers that can be copolymerized include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and 2-methyl-1. Conjugated dienes such as 1,3-pentadiene, 1,3-hexadiene, 1,6-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene; N-methylmaleimide And α, β-unsaturated carboxylic imides such as N-phenylmaleimide; α, β-unsaturated nitriles such as (meth) acrylonitrile; and the like.

(N1 and n2)
One or two of the A parts are bonded to the B part via Y. In addition, 2 to 16, preferably 4 to 8 of BY (A) _n1 are bonded to X via B.

(Y)
Y is a group linking the A part and the B part, and represents a functional group having a structure capable of having an active halogen atom.
Here, the “functional group having a structure capable of having an active halogen atom” means a reactive atom having a structure in which, if a halogen atom is bonded, the halogen atom becomes an active halogen atom. A group.

  In the multi-branched polymer of the present invention, the functional group having a structure capable of having an active halogen atom of Y is preferably any of the following formulas (V), (VI), or (VII).

In formula (V), T represents a divalent electron-withdrawing group, R ²⁰ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or 6 to 6 carbon atoms. 10 represents an aryl group, an ester group having 1 to 10 carbon atoms, or an acyl group having 1 to 10 carbon atoms, R ²¹ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, An aryl group having 6 to 10 carbon atoms, an ester group having 1 to 10 carbon atoms, or an acyl group having 1 to 10 carbon atoms is represented.
In the formula, * indicates a binding position with the B part, and ** indicates a binding position with the A part. In the formulas (V), (VI) and (VII), the position which can have an active halogen atom is a carbon atom to which ** is attached, in other words, this is the same as before bonding with the B part. It means that an active halogen atom was bonded to the carbon atom of ** of Y.

In the formula (VI), R ²² is a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aryl group having 1 to 10 carbon atoms. Represents an ester group or an acyl group having 1 to 10 carbon atoms, and R ²³ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryl group having 6 to 10 carbon atoms, and a carbon number. A 1-10 ester group or a C1-C10 acyl group is represented.
In the formula (VII), R ²⁴ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an ester having 1 to 10 carbon atoms. R ²⁵ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryl group having 6 to 10 carbon atoms, or 1 carbon atom. Represents an ester group having 10 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms. R26 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryl group having 6 to 10 carbon atoms, an ester group having 1 to 10 carbon atoms, or an acyl group having 1 to 10 carbon atoms. Represent.
In R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ , examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom.
Examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group, t-butyl group, and n-hexyl group. It is done.
Examples of the aralkyl group having 7 to 12 carbon atoms include benzyl group and phenethyl group.
Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group, a naphthyl group, an azulenyl group, an indenyl group, an indanyl group, and a tetralinyl group.
Examples of the ester group having 1 to 10 carbon atoms include alkoxycarbonyl groups such as methoxycarbonyl group, ethoxycarbonyl group and n-propoxycarbonyl group; cycloalkyloxycarbonyl groups such as cyclopropyloxycarbonyl group and cyclopentyloxycarbonyl group; phenyloxy Aryloxycarbonyl groups such as carbonyl group and naphthyloxycarbonyl group can be mentioned,
Examples of the acyl group having 1 to 10 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, pentanoyl group, hexanoyl group, heptanoyl group, octanoyl group, acryloyl group and benzoyl group.

  As T in the formula (V), a group represented by the formula (t11) or (t21) is preferable, and a group represented by the formula (t11) is more preferable.

In the above formula (t11), Z ¹¹ is an oxygen atom, a sulfur atom, or Nr ⁷¹ (r ⁷¹ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an optionally substituted phenyl group, carbon And an alkylcarbonyl group having 1 to 10 carbon atoms, an optionally substituted phenylcarbonyl group, an alkylsulfonyl group having 1 to 10 carbon atoms, or an optionally substituted phenylsulfonyl group. Represents a group.
Here, as a C1-C6 alkyl group, a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group, n-hexyl group Etc.
Examples of the alkylcarbonyl group having 1 to 10 carbon atoms include acetyl group, propionyl group, butyryl group, pentanoyl group, hexanoyl group, heptanoyl group, octanoyl group and the like.
Examples of the alkylsulfonyl group having 1 to 10 carbon atoms include methylsulfonyl group, ethylsulfonyl group, isopropylsulfonyl group, n-butylsulfonyl group, s-butylsulfonyl group, isobutylsulfonyl group, t-butylsulfonyl group, and n-hexylsulfonyl group. Groups and the like.
As the substituent of the phenyl group which may have a substituent, the phenylcarbonyl group which may have a substituent and the phenylsulfonyl group which may have a substituent, a fluorine atom, a chlorine atom, a bromine atom Halogen atoms such as methyl groups, ethyl groups, n-propyl groups, phenyl groups, naphthyl groups, benzyl groups, etc .; acyl groups such as acetyl groups, benzoyl groups; hydrocarbon oxys such as methoxy groups, phenoxy groups, etc. Group; alkylthio group such as methylthio group; alkylsulfinyl group such as methylsulfinyl group; alkylsulfonyl group such as methylsulfonyl group; and the like.

(Example of multi-branched polymer)
Examples of the multibranched polymer of the present invention include the following.

In the formula, A, B, Y, and n1 have the same definition as described above, and d1 to d4 each independently represent an arbitrary natural number.
In particular, as the multibranched polymer of the present invention, those represented by the following formula (VIII) are preferable.

In the formula, Z represents (CH ₂ ) q or a p-phenylene group, q represents an integer of 0 to 3, and each R independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituent. An aryl group having 6 to 10 carbon atoms which may have a group, a halogen atom or an alkoxyl group having 1 to 6 carbon atoms, each n3 independently represents an integer of 0 to 3; Each n4 independently represents any integer of 1 to 3.
Here, examples of (CH ₂ ) q include a single bond, a methylene group, an ethylene group, and a trimethylene group.
Examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, and t-butyl group.
Examples of the alkoxy group having 1 to 6 carbon atoms include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, s-butoxy group, isobutoxy group, t-butoxy group and the like.
Examples of the aryl group having 6 to 10 carbon atoms which may have a substituent include halogen atoms such as fluorine atom, chlorine atom and bromine atom; methyl group, ethyl group, n-propyl group, phenyl group, naphthyl group, Hydrocarbon groups such as benzyl groups; acyl groups such as acetyl groups and benzoyl groups; hydrocarbon oxy groups such as methoxy groups and phenoxy groups; alkylthio groups such as methylthio groups; alkylsulfinyl groups such as methylsulfinyl groups; And phenyl group, naphthyl group and the like, which may be substituted by alkylsulfonyl group and the like.

  The weight average molecular weight (Mw) of the multibranched polymer of the present invention is in the range of 10,000 to 2,000,000, preferably 50,000 to 1,000,000. The multibranched polymer of the present invention has a molecular weight. A controlled polymer.

(Method for producing multi-branched polymer)
Although the manufacturing method of the multibranched polymer of this invention can be manufactured similarly to the method described in international publication WO2006 / 016665 pamphlet, it will be as follows when it describes briefly.
A compound represented by the formula: X [B-Y] _n2 and a compound having a polymerizable unsaturated bond are polymerized under living radical polymerization conditions.

In the formula: X ′ [B′-Y ′] _{n2 ′} , B ′, X ′ and n2 ′ are the same as X, B and n2 in the formula X [BY (A) _n1 ] _n2 respectively. It is.
Y ′ represents a functional group represented by the following formula (VIII), formula (IX) or formula (X).

In the formula (VIII), T ¹ is the same as T in the formula (V), and R ²¹⁰ and R ²¹¹ are the same as R ²⁰ and R ^{21 in} the formula (V), respectively.
G ¹ represents a halogen atom such as a chlorine atom, a bromine atom, or an iodine atom.
In the formula (IX), R ²¹² and R ²¹³ are the same as R ²² and R ^{23 in} the formula (VI).
G ² is a halogen atom the same as the ^{G 1.}
In the formula (X), R ²¹⁴ and R ²¹⁵ are the same as R ²⁴ and R ^{25 in} the formula (VII).
G ³ represents the same halogen atom as G ¹ .

As a polymerization method of the compound represented by the formula: X ′ [B′-Y ′] _n2 and the compound having a polymerizable unsaturated bond, the compound represented by the formula (VII), A monomer solution containing a compound having a saturated bond, other monomers that can be copolymerized as required, and a reaction solvent is charged in a reaction vessel in a batch or in the course of reaction, and under an inert gas atmosphere such as nitrogen or argon as required. Heat, radical polymerization method in which polymerization is performed using a commercially available radical initiator (azo initiator, peroxide, etc.); the compound represented by the formula: X ′ [B′-Y ′] _n2 ; A monomer solution containing a compound having a saturated bond, other monomers that can be copolymerized if desired, and a reaction solvent is charged into a reaction vessel all at once or during the reaction, and stirred in an inert gas atmosphere such as nitrogen or argon. , Anionic polymerization initiator Anionic polymerization performed dropping the polymerization; and the living radical polymerization method and the like, in a narrow dispersion, in that the hyperbranched polymer molecular weight is controlled can be efficiently obtained, a living radical polymerization method is preferred.

As a method of polymerizing the compound represented by the formula: X ′ [B′-Y ′] _n2 and the compound having a polymerizable unsaturated bond under living radical polymerization conditions,
(A) Living radical polymerization method in which the compound represented by the formula: X ′ [B′-Y ′] _n2 is used as a polymerization initiator and a transition metal complex is used as a catalyst to perform a polymerization reaction, or (B) stable radical system initiation And living radical polymerization using an agent. Among these, the living radical polymerization method (A) is preferable from the viewpoint of obtaining the target multi-branched polymer more efficiently.

As a method of forming the arm portion by the living radical polymerization method,
(1) A method of forming an arm portion composed of a homopolymer using a compound having a kind of living radical polymerizable unsaturated bond,
(2) A method in which a compound having a plurality of living radical polymerizable unsaturated bonds is simultaneously added to the reaction system to form an arm portion made of a random copolymer,
(3) A method in which a compound having a plurality of living radically polymerizable unsaturated bonds is sequentially added to a reaction system to form an arm portion composed of a block copolymer,
(4) A method of changing the composition ratio of a compound having a plurality of living radical polymerizable unsaturated bonds over time to form an arm portion made of a gradient copolymer,
Etc.

  Of these, the narrowly dispersed multi-branched polymer can be obtained, and therefore, the method (3) of forming an arm portion composed of a block copolymer bonded in block units is preferred. According to this method, even when a compound having a functional group in the molecule is polymerized, it is not necessary to protect the functional group as in the living anion polymerization method, which is advantageous.

(Crosslinking agent)
The crosslinker of the present invention has at least two functional groups that are reactive with the hydroxyl groups of the hyperbranched polymer. Examples thereof include aminoplasts and polyisocyanates containing methylol and / or methylol ether groups.

  Aminoplasts are obtained from the reaction of aldehydes with amines or amides, and include melamine, urea, benzoguanamine, etc., and aminoplasts containing methylol and / or methylol ether groups are 1-4 carbon atoms. It is obtained by etherification with an alcohol containing

The polyisocyanate may be an aliphatic or aromatic polyisocyanate, or a mixture thereof.
For example, linear aliphatic isocyanates such as 1,4-tetramethylene diisocyanate and 1,6-hexamethylene diisocyanate; alicyclic diisocyanates such as isophorone diisocyanate and 4,4′-methylene-bis-cyclohexyl isocyanate; p-phenylene diisocyanate , Aromatic diisocyanates such as diphenylmethane-4,4′-diisocyanate, 2,4- or 2,6-toluene diisocyanate, naphthylene-1,5-diisocyanate; triphenylmethane-4,4 ′, 4 ″ -triisocyanate Higher molecular weight polyisocyanates such as 1,2,4-benzene triisocyanate and polymethylene polyphenyl isocyanate. Diisocyanate biurets and isocyanurates (eg, isocyanurates of hexamethylene diisocyanate, biurets of hexamethylene diisocyanate, and isocyanurates of isophorone diisocyanate), including mixtures thereof, can also be used.

  Reaction products of isocyanate prepolymers such as polyisocyanates with polyols such as neopentyl glycol and trimethylol propane or polymer polyols such as polycaprolactone diol and triol can also be used.

(catalyst)
For the reaction between the hydroxyl group of the multi-branched polymer and the polyisocyanate crosslinking agent, a catalyst such as an acid, a base, or various metal compounds can be used.
For example, dimethyl phosphate, di-n-butyl phosphate, o-phenyl soda, potassium oleate, triethylamine, triethylenediamine, hexamethylenetetramine, N-methylmorpholine, N-methylmorpholine, N-methylpiperazine, N, N '-Dimethylpiperazine, N, N'-dimethylbenzylamine, N, N'-dimethyldodecylamine, N, N, N', N'-tetramethylethylenediamine, N, N, N ', N'-tetramethyl- 1,3-diaminobutane, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5-diazabicyclo [4.3.0] non-5-ene, tin octoate, dibutyltin dilaurate, Dioctyltin dilaurate, dioctyltin diacetate, dioctyltin versatate, dibutyltin oxa Ito, dioctyltin oxide, dioctyltin dichloride, tri-n-butyltin chloride, tetra-n-butyltin, trimethyltin hydroxide, 2-ethylhexyl titanate, 2-ethylhexoate iron, manganese naphthenate, zinc naphthenate, naphthene Copper acid, lead naphthenate, nickel naphthenate, cobalt naphthenate, iron chloride, tin chloride, antimony trichloride, bismuth nitrate, tin octylate, bismuth tris (2-ethylhexanoate).

(Manufacture of mesh polymer)
The equivalent ratio of the hydroxyl group in the multi-branched polymer to the reactive functional group in the cross-linking agent in the solvent is from 1: 0.5 to 2, preferably 1: 0.8. The reaction is carried out in the range of -1.2.
The temperature of the reaction is 10 to 140 ° C, preferably 20 to 70 ° C.
Although it does not restrict | limit especially as a use solvent, For example, Aromatic hydrocarbons, such as benzene, toluene, xylene; Aliphatic hydrocarbons, such as hexane, heptane, and octane; Alicyclic groups, such as cyclopentane, cyclohexane, and cyclooctane Hydrocarbons; ketones such as acetone, methyl ethyl ketone, cyclohexanone; tetrahydrofuran, dioxane 1,2-dimethoxyethane, 1,2-diethoxyethane, bis (2-methoxyethyl) ether, bis (2-ethoxyethyl) ether, Ethers such as 1,2-bis (2-methoxyethoxy) ethane; esters such as ethyl acetate, butyl acetate, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate; γ- Lactones such as til lactone and γ-valerolactone; Amides such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone; Examples thereof include sulfoxides such as sulfoxide, sulfolane, 1,3-propanesulfone and 1,4-butanesulfone; and nitriles such as acetonitrile and propiononitrile.
These solvents can be used alone or in combination of two or more.

2. Polymer Gel Electrolyte The polymer gel electrolyte of the present invention comprises a network polymer obtained by reacting a multi-branched polymer represented by the formula: X [BY (A) _n1 ] _n2 and a crosslinking agent, and a support thereof It is characterized by containing the electrolyte solution made.

  The network polymer of the present invention is useful as a raw material for producing a polymer gel electrolyte. That is, the polymer gel electrolyte composition is obtained by absorbing and supporting the electrolytic solution on the network polymer of the present invention obtained by the crosslinking reaction.

  The polymer gel electrolyte composition is preferably in the form of a sheet, film or film. When producing a polymer gel electrolyte sheet, after processing the network polymer into a sheet shape, a film shape, a film shape, etc., the electrolyte solution is absorbed and supported to obtain a polymer gel electrolyte composition sheet. In this case, the degree of freedom of the processed surface is widened, which is a great advantage in application.

  The polymer sheet can be formed into a sheet by forming a network polymer film on a carrier. A sheet-like network polymer is obtained through a step of coating the network polymer solution obtained by the crosslinking reaction and volatilizing the organic solvent.

  As the carrier to be used, the material, size, shape and the like are not particularly limited as long as the network polymer solution can be applied. Among them, those having excellent chemical resistance, heat resistance and peelability, such as release paper, release films such as polyolefin and polyester base materials, silicon films, and polytetrafluoroethylene are desirable.

  The method for coating the network polymer solution on the carrier is not particularly limited, and a known coating method can be employed. For example, a method of pouring a network polymer solution onto a carrier, roll coater method, gravure coater, knife coater, kiss coater, screen coating method, doctor blade method, bar coating method, curtain coater method, spin coating method, dip method, casting method And various coating means such as spray coating and extrusion coater.

  The solid content concentration of the network polymer solution is not particularly limited, but specifically, a range of 0.5 to 30% by weight can be preferably exemplified. If it is less than 0.5% by weight, the concentration is too dilute, and if it is more than 30% by weight, the film thickness cannot be controlled.

After casting or coating, the solvent is removed by a method such as distillation under normal or reduced pressure, heat drying, etc., but it is preferable to include a step of heat treatment in a state containing at least the solvent. As pre-processing or post-processing steps other than this step, steps such as distillation under reduced pressure and heat drying may be further included.
The temperature for heating is not particularly limited, but is preferably near the boiling point of the solvent used or the glass transition temperature of the polymer or higher.

  The obtained sheet-like network polymer can be suitably used as a gel electrolyte layer of a gel electrolyte battery having a positive electrode, a negative electrode, and a gel electrolyte layer. That is, an electrolytic solution is injected with a network polymer sandwiched between the positive electrode and the negative electrode. Alternatively, a polymer gel electrolyte battery can be obtained by sandwiching a polymer gel electrolyte in which an electrolytic solution is previously absorbed and supported by a network polymer between the positive electrode and the negative electrode.

In the gel electrolyte battery, a separator can be used in combination with the polymer gel electrolyte. The separator can be a microporous membrane made of polyolefin such as polyethylene or polypropylene, or a nonwoven fabric made of polyolefin fiber, polyester fiber, or glass fiber.
There is no particular limitation on the method of absorbing and supporting the electrolyte solution on the polymer sheet, a method of injecting the electrolyte solution after forming a battery element sandwiched between the positive electrode and the negative electrode, or casting the electrolyte solution on the polymer sheet And a method such as impregnation in an electrolytic solution, spray coating of the electrolytic solution on a polymer sheet, and the like.

As a network polymer used for the polymer gel electrolyte of the present invention, the A in the multi-branched polymer has a weight ratio of the repeating unit (I) to the repeating (II) of 30/70 to 60/40. The weight average molecular weight of the network polymer by GPC-MALLS is preferably 10,000 to 2,000,000.
The network polymer preferably has a molecular weight controlled, is narrowly dispersed, and has an intermolecular cross-linked structure. Such a polymer solid electrolyte has good electrolytic solution retention, high ionic conductivity, and high gel membrane strength.

As the electrolytic solution to be absorbed and supported by the network polymer sheet, a solution obtained by dissolving an electrolyte salt in a polar organic solvent is preferably used.
The organic solvent to be used is not particularly limited as long as it is a polar organic solvent having 10 or less carbon atoms generally used in lithium secondary batteries.
For example, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, 1,2-dimethoxyethane, 1,2-diethoxyethane, bis (2-methoxyethyl) ether, bis (2-ethoxy Ethyl) ether, 1,2-bis (2-methoxyethoxy) ethane, γ-butyllactone, γ-valerolactone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, sulfoxide: sulfolane 1,3-propanesulfone, 1,4-butanesulfone, acetonitrile, propiononitrile and the like.
These polar organic solvents may be used alone or in combination of two or more.

The electrolyte salt to be dissolved in the organic solvent is not particularly limited, and an electrolyte containing ions that are desired to be carriers by charge may be used. It is desirable that the dissociation constant in the polar organic solvent is large, and alkali metal Salts, quaternary ammonium salts such as (CH ₃ ) ₄ NBF ₆ , quaternary phosphonium salts such as (CH ₃ ) ₄ PBF ₆ , transition metal salts such as AgClO _4, hydrochloric acid, perchloric acid, borohydrofluoric acid, etc. At least one selected from the group consisting of protic acids is preferred, the use of alkali metal salts, quaternary ammonium salts, quaternary phosphonium salts or transition metal salts is more preferred, and alkali metal salts are more preferred.

Specific examples of the alkali metal salt include LiCF ₃ SO ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiC (SO ₂ CF ₃ ) ₃ , LiC (CH ₃ ) (SO ₂ CF ₃ ) ₂ , LiCH (SO ₂ CF _{3) 2, LiCH 2 (SO} 2 CF 3), LiC 2 F 5 SO 3, LiN (SO 2 C 2 F 5) 2, LiN (SO 2 CF 3), LiB (SO 2 CF 3) 2, LiBC 4 _{O 8, LiPF 6, LiSbF 6} , LiClO 4, LiCl, LiI, LiBF 4, LiSCN, LiAsF 6, NaCF 3 SO 3, NaPF 6, NaClO 4, NaI, NaBF 4, NaAsF 6, KCF 3 SO 3, KPF 6 , KI, LiCF ₃ CO ₃ , NaClO ₃ , NaSCN, KBF ₄ , KPF ₆ , Mg (ClO ₄ ) ₂ Mg (BF ₄ ) _{2 and the} like. These electrolyte salts can be used alone or in combination of two or more. Among these, lithium salts are particularly preferable.
These may be used in combination. The concentration of the electrolyte salt to be dissolved is preferably in the range of usually 0.1 mol / L to 3 mol / L, particularly 0.5 mol / L to 1.5 mol / L.

In addition, the polymer gel electrolyte of the present invention has excellent mechanical strength to such an extent that a self-supporting film can be formed, and has excellent ionic conductivity over a wide temperature range of -20 to 60 ° C. The ionic conductivity of the polymer gel electrolyte of the present invention at −20 to 60 ° C. is usually 1.0 × 10 ⁻² (S / cm) to 1.0 × 10 ⁻⁴ (S / cm).

  When the polymer gel electrolyte of the present invention is used for a battery, for example, a method in which a reticulated polymer sheet is inserted between electrodes and an electrolytic solution is injected; a reticulated polymer sheet and an electrolytic solution are first placed on the electrode, and a roll coater is used. The polymer gel electrolyte is formed on the electrode by various means such as a method, a curtain coater method, a spin coat method, a dip method, or a cast method, and the other electrode is disposed; It can be produced by preparing a polymer gel electrolyte that absorbs and carries a liquid and then sandwiching it between electrodes.

The battery using the solid polymer electrolyte of the present invention has a withstand voltage of 4.2 V or higher, preferably 4.5 V or higher. It is a battery with high practicality that not only has a voltage resistance of 4.5 V at room temperature or high temperature, but also exhibits high conductivity and maintains good characteristics in charge / discharge tests. Specifically, the ion conductivity at 30 ^{℃: 10} -3 S / cm or more, preferably the conductivity at 10 ° ^C.: having ¹⁰ -3 S / cm or more ionic conductivity. The withstand voltage can be measured by a + 5V stability test.

  The battery using the polymer gel electrolyte of the present invention has an energy density of 100 Wh / kg or more, preferably 150 Wh / kg or more, or a volumetric energy density of 350 Wh / kg or more, preferably 370 Wh / kg or more. A polymer gel electrolyte battery having a high energy density, comprising a polymer gel electrolyte having the energy density.

  Batteries using the polymer gel electrolyte obtained are, for example, notebook computers, mobile phones, cordless phone machines, electronic notebooks, calculators, LCD TVs, electric shavers, electric tools, electronic translators, voice input devices, memory cards, backups. Power supply for power supply, radio, headphone stereo, navigation system, etc., refrigerator, air conditioner, TV, water heater, microwave oven, dishwasher, washing machine, game machine, lighting device, toy, sensor device, active IC card , RF-IC tags, medical devices, automobiles, electric carts, robots, satellite power systems, power storage systems, and the like.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail using an Example, the scope of the present invention is not limited to an Example. The molecular weight distribution was analyzed by GPC-MALLS (gel permeation chromatography multi-angle light scattering detection method).

I Synthesis of multi-branched polymer (Synthesis Example 1)
1 Synthesis of Macroinitiator In a nitrogen-substituted 5000 mL four-necked flask, 290 g of dehydrated tetrahydrofuran (hereinafter abbreviated as THF), 2675 g of dehydrated toluene, DPE- (m-OTHP) 2: (1,1-bis [3- ( tetrahydropyran-2-yloxy) methyl phenyl] ethylene)) 28.8 g (70 mmol) was added and the reaction system was kept at -40 ° C. with stirring. To the reaction system, 28.7 g (70 mmol) of a n-butyllithium / hexane 1.6 mol / L solution was added and stirred for 30 minutes. Thereafter, 483.5 g (4642 mmol) of styrene was added to the reaction system for polymerization. Sampling was performed 40 minutes after the completion of the dropping, and the completion of polymerization was confirmed by gas chromatography. To this reaction system, 4.1 g (6.6 mmol) of 1,1,2,2tetrakis (4-ethoxycarbonylphenyl) ethane dissolved in 100 mL of dehydrated THF was added, and the reaction was continued for 30 minutes. Then, 112 g of methanol was added. The reaction was stopped. The reaction solution was charged with 37 g of 35% hydrochloric acid and reacted at 50 ° C. for 3 hours to remove THP. After confirming that the THP group was removed by NMR analysis, 10% water and 60% ethyl acetate were added to the polymerization solution, followed by liquid separation. 10% of water was again added to the polymerization solution and washed with water. The organic layer was concentrated to an about 50% polymer solution, 700 g of toluene was added, the mixture was concentrated again, and concentrated to about 800 g. Into this, 1000 g of dehydrated THF and 50 ml of triethylamine were added, and the reaction system was cooled to 10 ° C. with stirring. Then, 43.3 g (188 mmol) of bromoisobutyryl bromide was added, and after dropping, the mixture was returned to room temperature and stirred overnight. Went. After removing the TEA bromoacid salt by filtration, 800 g of THF and 1400 g of methanol were charged and allowed to stand overnight. The extracted lower layer was poured into a large amount of methanol to precipitate a polymer, which was filtered and washed. By drying at 50 ° C. for 5 hours under vacuum, 462 g of a white powdery polymer was obtained.
When this polymer solution was analyzed by GPC, it was a unimodal polymer having a molecular weight Mn = 46300 and a dispersity Mw / Mn = 1.03. Moreover, it was weight average molecular weight Mw = 91300 when measured by GPC-MALLS.

2 Synthesis of Star Polymer In a 5 L flask, 264 g (3 mmol) of the previously synthesized macro initiator, Blemmer PME-1000 (manufactured by NOF Corporation), 573 g (0.51 mol), 43 g (0.33 mol) of hydroxyethyl methacrylate, toluene 2640 g was charged and dissolved uniformly. After degassing and repeating the nitrogen substitution operation three times, 4.6 g (4.8 mmol) of dichlorotris (triphenylphosphine) ruthenium was added. After placing the flask in a bath preheated to 80 ° C., 3.6 g (19 mmol) of triethylamine was added and aged for 270 minutes. After cooling to room temperature, the reaction solution was applied to a column to remove the metal complex and unreacted monomers. The solvent was distilled off, followed by vacuum drying at 50 ° C. for 24 hours to obtain 550 g of a yellow viscous product. When this polymer was measured by GPC-MALLS, it was weight average molecular weight Mw = 173400. Moreover, PEO content was 44% from NMR.

(Synthesis Comparative Example 1) Synthesis of Linear Polymer 1 Synthesis of Macro Initiator In a 1 L flask, 90 g (81 mmol) of Bremer PME-1000, 10 g (77 mmol) of hydroxyethyl methacrylate and 300 g of toluene were charged and dissolved uniformly. After deaeration and repeating the nitrogen substitution operation three times, 0.48 g (0.5 mmol) of dichlorotris (triphenylphosphine) ruthenium and 0.19 g (1 mmol) of 2,2-dichloroacetophenone were added. The flask was placed in a bath preheated to 80 ° C., 0.26 g (2 mmol) of dibutylamine was added, and the mixture was aged for 45 hours. After cooling to room temperature, the reaction solution was applied to a column to remove the metal complex and unreacted monomers. The solvent was distilled off, followed by vacuum drying at 50 ° C. for 24 hours to obtain 59 g of a green viscous product. When this polymer was measured by GPC-MALLS, it was weight average molecular weight Mw = 154500.

2 Synthesis of linear polymer In a 500 mL flask, 28 g (0.19 mmol) of the previously synthesized macroinitiator, 84 g (806 mol) of styrene, and 112 g of toluene were charged and dissolved uniformly. After degassing and repeating the nitrogen substitution operation three times, 0.1 g (0.1 mmol) of dichlorotris (triphenylphosphine) ruthenium was added. After placing the flask in a bath preheated to 100 ° C., 0.05 g (0.4 mmol) of dibutylamine was added and aged for 28 hours. After cooling to room temperature, the reaction solution was applied to a column to remove the metal complex and unreacted monomers. After distilling off the solvent, it was diluted with THF and reprecipitated with a large amount of cold hexane. By vacuum-drying at room temperature for 24 hours, 41 g of a white polymer was obtained. When this polymer was measured by GPC-MALLS, it was weight average molecular weight Mw = 344900. Moreover, PEO content was 54% from NMR.

II Production of reticulated polymer film (Example 1)
A uniform polymer solution was prepared by dissolving the star polymer having a PEO content of 42 wt% obtained in Synthesis Example 1 in DMC (dimethoxy carbonate) so that the solid content concentration was 10 wt%. Next, to 20 ml of this solution was added 175 mg of trifunctional aliphatic crosslinking agent Duranate (registered trademark) (biuret of hexamethylene diisocyanate; product name 24A100 (Asahi Kasei Chemicals), NCO: 23.4 wt%) to the hydroxyl group of the star polymer. Equivalent amount), and 0.6 mg of dibutyltin dilaurate was further added as a catalyst.
The obtained polymer cross-linking solution was cast on a sheet substrate made of polytetrafluoroethylene and heated and vacuum dried at 70 ° C. for 1 hour and then at 100 ° C. for 3 hours to obtain a polymer composition having a film thickness of 100 to 200 μm ( 1) was prepared.

(Example 2)
The same preparation as described above is performed on 20 ml of the star polymer having a PEO content of 42 wt% obtained in Synthesis Example 1 using 81 mg of hexamethylene diisocyanate (bifunctional aliphatic crosslinking agent) and 0.6 mg of dibutyltin dilaurate as the crosslinking agent. As a result, a polymer composition (2) was obtained.

(Example 3)
A polymer composition (3) was obtained by preparing in the same manner as described above using 85 mg of tolylene diisocyanate (bifunctional aromatic crosslinking agent) as a crosslinking agent for 20 ml of a star-type polymer having a PEO content of 42 wt%. Dibutyltin dilaurate was not used as a catalyst.

(Comparative example)
With respect to the linear polymer having a PEO content of 39 wt% obtained in Synthesis Comparative Example 1, a polymer DMC solution having a solid content concentration of 10 wt% was prepared in the same manner as in the above example. The same preparation was performed on 20 ml of this solution using 66 mg of tolylene diisocyanate as a crosslinking agent to obtain a crosslinked polymer. Dibutyltin dilaurate was not used as a catalyst.
The obtained polymer cross-linking solution was cast on a sheet substrate made of polytetrafluoroethylene, and heated and dried under vacuum at 70 ° C. for 1 hour and then at 100 ° C. for 3 hours to form a polymer electrolyte composition having a film thickness of 100 to 200 μm. (4) was prepared.

III Preparation of polymer gel electrolyte membrane (Example 4)
In an argon atmosphere, the polymer composition (1), (2), (3) is peeled off from the sheet base material and immersed in the electrolyte solution, so that the polymer film carries the electrolyte solution and the intended polymer gel. Electrolyte membranes (1), (2) and (3) were obtained. As the electrolytic solution, a nonaqueous solvent of ethylene carbonate: diethylene carbonate = 1: 1 (volume ratio) having a LiPF ₆ concentration of 1 mol / L was used.
The weight of the polymer gel electrolyte membrane (1) was increased by 3.6 times when the gel membrane was formed compared to before the electrolyte was immersed, and the composition ratio of the polymer to the electrolyte supported at this time was 28:72 (weight ratio). It was.
The weight of the polymer gel electrolyte membrane (2) was increased by 5.0 times when the gel membrane was formed compared to before immersion in the electrolyte solution. At this time, the composition ratio of the polymer and the electrolyte solution carried was 20:80 (weight ratio). It was.
The weight of the polymer gel electrolyte membrane (3) was increased by 3.3 times when the gel membrane was formed before the electrolyte immersion, and the composition ratio of the polymer to the electrolyte supported at this time was 31:69 (weight ratio). It was.

  Any of the obtained polymer gel electrolytes can be used as a self-supporting membrane, and the following polymer gel physical property evaluation was possible.

(Comparative Example 2)
When the polymer electrolyte composition (4) was peeled off from the sheet substrate and immersed in the electrolytic solution in an argon atmosphere, a gel film that supported the electrolytic solution and could be used as a self-supporting film was not obtained.

(Comparative Example 3)
Under an argon atmosphere, MMA (methyl methacrylate): EDMA (ethylene glycol dimethacrylate): AIBN (azobisisobutyronitrile): electrolytic solution = 25.4: 1.3: 0.5: 72.8 (wt%) : Wt%), and a uniform pregel polymer solution was prepared according to the reference. A silicon plate (500 μm) was sandwiched between the two glass plates as a spacer, and the pregel polymer solution was added between them. A PMMA gel electrolyte membrane was obtained by putting a glass plate (petri dish) containing a prepolymer solution in a sealed bottle, plugging it, and heating in an oven at 80 ° C. for 1 hour.
The PMMA gel electrolyte membrane can be used as a self-supporting membrane, and the following polymer gel physical property evaluation could be performed.
(Reference: S. Kuwabata and M. Tomiyori, Journal of The Electrochemical Society, 149 (8) A988-A994 (2002))

(Evaluation of physical properties of polymer gel electrolyte)
The volume swelling rate, ionic conductivity, film strength, and electrical stability of the obtained polymer gel electrolyte were measured. The test method is described below.
1) Volume swell ratio As a test piece, a polymer gel electrolyte composition cut into 2 cm pieces was used. The polymer gel electrolyte composition before being immersed in the electrolytic solution and the vertical and horizontal sizes (X, Y) and area of the polymer gel electrolyte formed by being immersed in the electrolytic solution are digital microscopes (VHX-900, manufactured by Keyence Corporation) ) And the size change rate and the area change rate were calculated. The size change in the film thickness direction (Z) was measured with a film thickness meter.
The volume was calculated from the obtained size and area, and the volume swelling ratio was calculated from the volume change before and after immersion in the electrolyte.
The results are shown in Table 1 together with the gel composition.

The polymer gel electrolyte membrane (1) was equally swelled in all directions, that is, 1.5 times the size as compared with that before the immersion. Swelled 2.2 times as area and 3.3 times as volume.
In addition, the polymer gel electrolyte membranes (2) and (3) were also swelled isotropically, and swelled 3.9 times and 2.9 times in volume, respectively.

2) Ionic conductivity The polymer gel electrolyte is sandwiched between platinum electrodes with a diameter of 1 cm and the ionic conductivity is measured by complex impedance analysis using an impedance analyzer (Solartron-1260 type, Toyo Technica Co., Ltd.) in the frequency range of 100 to 10 MHz. did. The results are shown together with the gel composition. 2 shows a graph of ionic conductivity in FIG.

As can be seen from the results in FIG. 1, all showed better ionic conductivity than the PMMA of the comparative example. The conductivity of the gel electrolyte membrane depends on the amount of the electrolyte solution to be supported. In particular, the polymer gel electrolyte membrane (2) having a large amount of electrolyte solution showed a high ionic conductivity. Furthermore, from FIG. 1, the polymer gel electrolyte showed a good value exceeding the ion conductivity of 10 ⁻³ S / cm even at a low temperature of −20 ° C.

3) Film strength Tensile test pieces (10 mm x 30 mm, film thickness 200 µm) were made from polymer gel, and a desktop precision universal testing machine (Autograph AGS-J, Shimadzu Corporation) at a speed of 20 mm / min at 25 ° C. Tensile test was performed using a manufacturing plant. The film strength measurement results are shown in Table 3 using the breaking stress at which the test piece broke.
As can be seen from the results in Table 3, all films showed superior film strength as compared with the PMMA of the comparative example. The conductivity of the gel electrolyte membrane depends on the amount of the electrolyte solution to be supported, and in particular, the polymer gel electrolyte membrane (1) having an appropriate amount of electrolyte solution showed high membrane strength.

4) Electrical stability test A test cell was prepared with a polymer gel electrolyte sandwiched between platinum as a working electrode and lithium metal as a counter electrode / reference electrode.
After the natural potential (open circuit voltage) of the test cell is stabilized, the natural potential is started, and cyclic voltammetry measurement (CV measurement) is performed in the range of +4.5 V to +2 V (vs. Li / Li +) at 25 ° C. An automatic polarization system (HSV-110, Hokuto Denko Co., Ltd.) was used. The sweep speed was 1.0 mV / sec, and a CV curve was obtained. In particular, for the polymer gel electrolyte membranes (1) and (2), no increase in current value due to side reaction was observed, and good electrical stability was exhibited.

Claims (3)

The following formula: X [B-Y (A) _n1 ] _n2
Wherein A is the formula (I)

(Wherein R ¹ , R ² and R ³ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ¹ and R ³ may combine to form a ring. R ^4a and R ^4b each independently represent a hydrogen atom or a methyl group, and R ⁵ represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, an acyl group having 1 to 10 carbon atoms, or 3 to 3 carbon atoms. 20 represents a tri-substituted silyl group, m represents an integer of 1 to 100, and when m is 2 or more, R ^4a and R ^4b may be the same or different. A repeating unit represented by formula (II)

(Wherein, ^{R 6} and ^{R 8} each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, ^{R 6} and ^{R 8} may form a ring, ^{R 7} Is a hydrogen atom; a hydrocarbon group having 1 to 10 carbon atoms; a hydroxyl group; a hydrocarbon oxy group having 1 to 10 carbon atoms; a carboxyl group; an acid anhydride group; an amino group; an ester group; or a hydroxyl group, a carboxyl group, and an epoxy. Represents an organic group having at least one functional group selected from the group consisting of a group, an acid anhydride group, and an amino group, and R ⁹ consists of a hydroxyl group, a carboxyl group, an epoxy group, an acid anhydride group, and an amino group Represents an organic group having at least one functional group selected from the group.) Represents a random copolymer comprising a repeating unit represented by:
B is the formula (III)

(Wherein R ¹⁰ , R ¹¹ and R ¹² each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ¹³ represents an aryl group or a heteroaryl group). A polymer containing repeating units is represented.
X represents an organic group having three or more bonds with B, and Y represents a functional group having a structure capable of having an active halogen atom.
n1 represents 1 or 2, and n2 represents any integer of 2 to 16. )
A polymer gel electrolyte comprising a network polymer obtained by reacting a multi-branched polymer represented by the formula (I) and a crosslinking agent, and an electrolytic solution . The polymer according to claim 1, wherein the content of the repeating unit represented by the formula (IV) in the repeating unit represented by the formula (I) in the multi-branched polymer is 30 to 60% by weight. Gel electrolyte.

The multi-branched polymer represented by the following formula: X [B-Y (A) _n1 ] _n2 has the formula (VIII)

(In the formula, Z represents (CH ₂ ) q or a p-phenylene group, q represents an integer of 0 to 3, and each R independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, An aryl group which may have a substituent, a halogen atom, or an alkoxyl group having 1 to 6 carbon atoms, each n3 independently represents an integer of 0 to 3, and each n4 represents Independently represents an integer of 1 to 3.
A, B, Y, and n1 are the same as defined in claim 1, and each A, B, Y, and n1 may be the same or different. )
Polymer gel electrolyte according to claim 1 or 2 in a compound represented by.

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