JP2011238599A - Nonwoven fabric composite polymer solid electrolyte sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonwoven fabric composite polymer solid electrolyte sheet which allows thinning of a polymer solid electrolyte film and exploits an excellent adhesive property of polymer.SOLUTION: A nonwoven fabric composite polymer solid electrolyte sheet comprises a polymer electrolyte carried on a nonwoven fabric. The polymer electrolyte comprises: (A) at least one type of copolymer selected from a group consisting of a block copolymer having a block chain A containing a repeating unit represented by a formula (I) and a block chain B containing -[-C(R)(R)-C(R)(R)-]-, and a multibranched copolymer represented by a formula (III), X[B-Y(AB)](III),(where "AB" represents a random copolymer containing the repeating unit A represented by the formula (I) and the repeating unit B); and (B) an electrolyte salt.

Description

  The present invention relates to a nonwoven fabric composite polymer solid electrolyte sheet useful for a secondary battery in which a polymer electrolyte is supported on a nonwoven fabric.

With the improvement in performance of devices using lithium secondary batteries, demands for not only high battery capacity and long-term reliability but also shape diversity have become apparent. Further examples include a battery with a thinner and larger area, a stacked battery, a battery with a curved surface, and the like. In addition, demand for large-capacity lithium secondary batteries for use in recent hybrid vehicles and electric vehicles, and power storage facilities for power stabilization by wind power generation or solar power generation is expected.
In order to increase the capacity and energy density of a battery, an increase in the content of active materials and the use of higher-voltage active material materials have been pointed out, and the risk of battery heat generation and ignition has been pointed out. In addition, the battery casing is being laminated to reduce the thickness and flexibility of the battery. However, as long as the electrolytic solution is used, it cannot escape from the risk of liquid leakage.
For this reason, studies have been made on batteries that are replaced with solid electrolytes that do not contain an electrolytic solution in order to reduce the thickness of lithium secondary batteries and improve shape processability. Solid electrolyte types include polymer solid electrolytes and inorganic solid electrolytes.

  However, since the inorganic solid electrolyte is generally a powder, its molding processability is poor, and ionic conduction is due to interfacial contact between particles. Therefore, it is very difficult to create a powder molded sheet in a large area and to control the interfacial resistance between particles and maintain the uniformity of quality. Also, the inorganic solid electrolyte has no adhesion. Therefore, the interfacial resistance with the battery member such as an electrode is increased, and further, the electrode active material is generated due to a defective product or a short circuit due to shear movement with the positive electrode or the negative electrode during battery preparation or transportation, and further due to rubbing. Or the molded solid electrolyte may be lost.

On the other hand, examples of the polymer solid electrolyte include an electrolyte containing a polyether polymer having an ethylene oxide unit of polyethylene oxide or polypropylene oxide. The ethylene oxide unit in the polymer coordinates lithium ions, and the lithium ions are transported by the segment motion of the polymer to develop ionic conductivity. However, generally, the ionic conductivity of the polymer solid electrolyte is low.
In a lithium secondary battery having such a polymer solid electrolyte, it is necessary to reduce the battery internal resistance by reducing the distance between the positive electrode and the negative electrode, that is, to make the solid electrolyte layer thin. However, since solid polymer electrolytes having polymers such as polyethylene oxide and polypropylene oxide have insufficient mechanical strength, there has been a problem that the frequency of internal short circuits increases when the thickness of the electrolyte layer is reduced.

Accordingly, the present inventors have a narrow dispersion block copolymer polymer of a polymer of an acrylate derivative having a polyalkylene oxide chain at an ester site and polystyrene as a main skeleton, and by expressing a microphase separation structure, A polymer (MES polymer) having both high ionic conductivity and film strength was developed (Patent Documents 1 and 2).
By using the MES polymer, a lithium secondary battery composed of a solid electrolyte layer having a thickness of about 50 μm can be obtained. However, it is difficult to further reduce the film thickness to 50 μm or less, and for battery production, a mixed solution in which the polymer and lithium salt are dissolved in an organic solvent is cast on the positive electrode or negative electrode. Had to do.

International Publication No. 2004/009663 Pamphlet International Publication No. 2006/016665 Pamphlet

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a nonwoven fabric composite polymer solid electrolyte sheet having features of enabling further thinning of the polymer solid electrolyte and excellent adhesion. It is.

  As a result of intensive studies to solve the above problems, the present inventors can obtain a thin film nonwoven fabric composite polymer solid electrolyte sheet having excellent ionic conductivity and adhesion by supporting a polymer electrolyte on the nonwoven fabric. The present invention has been completed.

That is, the present invention is (1) a nonwoven fabric,
(A) 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 2 to 100, and when m is 2 or more, R ^4a and R ^4b may be the same or different. A block chain A having a repeating unit represented by formula (II)

(Wherein R ^{6 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ⁹ represents an aryl group). A block copolymer having B and the formula (III)
Formula X [B-Y (A) _n1 ] _n2 (III)
[Wherein, X represents an organic group having 3 or more bonds. A is the formula (I)

Wherein R ^{1 to} R ⁵ and m are the same as defined above, and the formula (II)

(Wherein R ^{6 to} R ⁹ are the same as defined above), and represents a random copolymer having a repeating unit. B is the formula (IV)

(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). Represents a polymer containing units.
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.
n1 represents 1 or 2, and n2 represents any integer of 2 to 16. At least one selected from the group consisting of multibranched copolymers represented by:
(B) a nonwoven fabric composite polymer solid electrolyte sheet carrying a polymer electrolyte containing an electrolyte salt;
(2) The total molar ratio ((I) / (II)) of the repeating unit represented by the formula (I) and the repeating unit represented by the formula (II) of the block copolymer is 1/30 to The nonwoven fabric composite polymer solid electrolyte sheet according to (1) above, which is in a range of 30/1,
(3) The nonwoven fabric according to (1) or (2) above, wherein the block copolymer has a number average molecular weight of 5,000 to 1,000,000 by GPC using polystyrene as a standard. Composite polymer solid electrolyte sheet,
(4) The degree of polymerization of the repeating units (I) and (II) in the random copolymer of A in the multi-branched copolymer is 30 to 2,000, respectively. (3) The nonwoven fabric composite polymer solid electrolyte sheet according to any one of the above, and
(5) Any of the above (1) to (4), wherein the multi-branched copolymer has a weight average molecular weight (Mw) by GPC-MALLS method of 10,000 to 2,000,000 The nonwoven fabric composite polymer solid electrolyte sheet described in 1.

  ADVANTAGE OF THE INVENTION According to this invention, the thin film nonwoven fabric composite polymer solid electrolyte sheet excellent in ionic conductivity and adhesiveness is obtained, and the all-solid-state lithium secondary battery which shortened the distance between electrodes can be provided. Furthermore, since the polymer used for the polymer electrolyte has adhesiveness, no shear movement between the electrodes occurs, so that the battery can be manufactured efficiently.

It is a figure which shows the ionic conductivity of the nonwoven fabric composite polymer solid electrolyte sheet (1) and (2) in the range of 60 degreeC--20 degreeC. It is a figure which shows the cyclic voltammetry measurement result of a lithium secondary battery using a nonwoven fabric composite polymer solid electrolyte sheet (1).

Hereinafter, the present invention will be described in detail.
The nonwoven fabric composite polymer solid electrolyte sheet of the present invention is one in which the following polymer electrolyte is supported on a nonwoven fabric.

1 Polymer Electrolyte The polymer electrolyte contains the following polymer and electrolyte salt.
1) Polymer As the polymer, at least one of the following block copolymers and multi-branched copolymers is used.

1-1) Block copolymer The block copolymer used in the present invention has 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 2 to 100, and when m is 2 or more, R ^4a and R ^4b may be the same or different. A block chain A having a repeating unit represented by formula (II)

(Wherein R ^{6 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ⁹ represents an aryl group). A block copolymer having B.

  The copolymer has at least one block chain A having a repeating unit represented by the formula (I) and one block chain B having a repeating unit represented by the formula (II). As for the copolymer of this invention, the copolymer which has arrangement | sequences, such as AB, BA, ABAA, BABB, is illustrated, for example.

Here, “the block chain A having a repeating unit represented by the formula (I)” means that the block chain A contains one or more repeating units represented by the formula (I), And it means that other repeating units other than those may be included. The same applies to “block chain B having a repeating unit represented by formula (II)”.
In addition, when including two or more kinds of repeating units represented by the formula (I), and when including other repeating units as constituent units, the polymerization mode of each repeating unit is not particularly limited, and random polymerization, block polymerization Any polymerization method such as alternating polymerization may be used.

  In addition, each block chain has a sequence such as A-B, B-A, A-B-A, B-A-B, etc., even if each block chain is directly bonded, a linking group, a polymer chain It means that other structural units may be combined with each other. Here, examples of the linking group include low-molecular linking groups such as an oxygen atom and an alkylene group, and the polymer chain may be a homopolymer or a binary or higher copolymer. There is no particular limitation on the bonding state therein, and it may be random, block, or a gradient in which the component ratio gradually changes.

In the repeating unit represented by the formula (I), 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-heptini Group, alkynyl group such as 1-octynyl group, 1-decynyl group; cycloalkyl group such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group; phenyl group, naphthyl group, etc. Aryl groups such as benzyl group and phenethyl group.
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, m represents any integer of 2 to 100, preferably any integer of 5 to 100, and any one of 10 to 100 Such an integer is preferred. The value of m in each repeating unit may be the same or different, and R ^4a and R ^4b may be the same or different.

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.
Here, examples of the hydrocarbon group having 1 to 10 carbon atoms include the same groups as those in the above formulas 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.

R ^{1 to} R ⁵ may have a substituent on an appropriate carbon atom. Specific examples of such a substituent include a halogen atom such as a fluorine atom, a chloro atom, or a bromine atom, a methyl group, Hydrocarbon groups such as ethyl group, n-propyl group, phenyl group, naphthyl group and benzyl group, acyl groups such as acetyl group and benzoyl group; hydrocarbon oxy groups such as nitrile group, nitro group, methoxy group and phenoxy group; Examples thereof include a methylthio group, a methylsulfinyl group, a methylsulfonyl group, an amino group, a dimethylamino group, and an anilino group.

Although the degree of polymerization of the repeating unit represented by formula (I) depends on the value of m, it is preferably 10 or more, and more preferably 20 or more.
Specific examples of the monomer that is a raw material of the repeating unit represented by the formula (I) include the following compounds. These repeating units may be used alone or in combination of two or more.
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), acetyloxypolyethylene glycol (Meth) acrylate, benzoyloxypolyethylene glycol (meth) acrylate, trimethylsilyloxypolyethylene glycol (meth) acrylate, t-butyldimethylmethylicyl Oxy polyethylene glycol (meth) acrylate, methoxy polyethylene glycol cyclohexene-1-carboxylate, methoxy polyethylene glycol - cinnamate.

In the repeating unit represented by the formula (II), R ^{6 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and the hydrocarbon having 1 to 10 carbon atoms is methyl. Group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group, t-butyl group and other alkyl groups; phenyl group, naphthyl group, benzyl group and other aryl groups or arylalkyl Groups and the like. R ⁹ represents an aryl group having 6 to 14 carbon atoms such as a phenyl group, a phenyl group, a naphthyl group, or an anthracenyl group.

R ^{6 to} R ⁹ may have a substituent on an appropriate carbon atom, and as such a substituent, specifically, a halogen atom such as a fluorine atom, a chloro atom, or a bromine atom, Hydrocarbon groups such as methyl group, ethyl group, n-propyl group, phenyl group, naphthyl group and benzyl group, acyl groups such as acetyl group and benzoyl group, hydrocarbons such as nitrile group, nitro group, methoxy group and phenoxy group Examples thereof include an oxy group, a methylthio group, a methylsulfinyl group, a methylsulfonyl group, an amino group, a dimethylamino group, and an anilino group.

The degree of polymerization of the repeating unit represented by the formula (II) is preferably 5 or more, and more preferably 10 or more. Specific examples of the monomer that is a raw material for the repeating unit represented by the formula (II) include the following compounds. These repeating units may be used alone or in combination of two or more.
Styrene, o-methylstyrene, p-methylstyrene, pt-butylstyrene, α-methylstyrene, pt-butoxystyrene, mt-butoxystyrene, 2,4-dimethylstyrene, m-chlorostyrene, Aryl compounds such as p-chlorostyrene, 4-carboxystyrene, vinylanisole, vinylbenzoic acid, vinylaniline, vinylnaphthalene, 9-vinylanthracene.

  The block copolymer used in the present invention can contain a repeating unit different from the repeating units represented by the formulas (I) to (II) as a constituent unit, and as a monomer as a raw material of such a repeating unit. The following compounds can be exemplified. These repeating units can be used in the block chains A and B or as a block chain other than the block chains A and B. These repeating units may be used alone or in combination of two or more.

  Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, (meth) acrylic Isobornyl acid, dicyclopentenyl (meth) acrylate, 1-adamantyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, 1-methyleneadamantyl (meth) acrylate, (meth) acrylic acid 1 -Ethylene adamantyl, 3,7-dimethyl-1-adamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate, norbornane (meth) acrylate, menthyl (meth) acrylate, n- (meth) acrylate Propyl, isopropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate , Isomethyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofuranyl (meth) acrylate, tetrahydropyranyl (meth) acrylate, (meth) (Meth) acrylic acid such as 3-oxocyclohexyl acrylate, butyrolactone (meth) acrylate, mevalonic lactone (meth) acrylate, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,6-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene , Conjugated dienes such as chloroprene, N-methylmaleimide, N-phenylmale alpha, such as de, beta-unsaturated carboxylic acid imides, (meth) alpha, such as acrylonitrile, beta-unsaturated nitriles and the like.

  The total molar ratio ((I) / (II)) of the repeating unit represented by the formula (I) and the repeating unit represented by the formula (II) is in the range of 1/30 to 30/1. Is preferred. When the repeating unit represented by the formula (I) is less than 1/30, sufficient conductivity cannot be obtained, and when it is more than 30/1, sufficient thermal characteristics and physical characteristics cannot be obtained. When the repeating unit represented by the formula (II) is less than 1/30, sufficient thermal characteristics and physical characteristics cannot be obtained, and when it is more than 30/1, sufficient conductivity cannot be obtained.

  The number average molecular weight of the block copolymer used in the present invention by GPC using polystyrene as a standard is not particularly limited, but is preferably in the range of 5,000 to 1,000,000. When the number average molecular weight is less than 5,000, thermal characteristics and physical characteristics are deteriorated, and when it is larger than 1,000,000, moldability or film formability is deteriorated. Further, the ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) is not particularly limited, but in order to form a microphase separation structure described later, 1.01 to 2.50, A range of 1.01-1.50 is preferred.

  The copolymer of the present invention is preferably configured to exhibit a microphase separation structure in the membrane structure in order to maintain high ionic conductivity as a nonwoven fabric composite polymer solid electrolyte sheet. It is preferable to adopt a configuration that expresses a phase separation structure.

(Method for producing block copolymer)
The block copolymer used in the present invention can be produced by a known production method, for example, the method described in JP-A No. 2004-107641.
For example, it can be manufactured as follows.
A compound represented by the following formula (V), a compound represented by the formula (VI), and, if necessary, another copolymerizable compound, a transition metal complex as a catalyst, and an organic containing one or more halogen atoms It can be produced using a known method such as a living radical polymerization method using a halogen compound as a polymerization initiator, a living radical polymerization method using a stable radical, or a living anion polymerization method. A living radical polymerization method using an organic halogen compound containing one or more as a polymerization initiator can be preferably exemplified.

Here, R _{1 to} R ₉ and m in the formulas (V) and (VI) represent the same meaning as described above.
More specifically,
(I) First, a macroinitiator containing each block chain such as a bifunctional block chain obtained by reacting the compound represented by the formula (V) with a bifunctional initiator in a living radical polymerization method. , A method for producing a block chain by reacting with monomers constituting other block chains and then extending the block chain,
(B) A compound represented by the formula (VI) is used in place of the formula (V), a monofunctional initiator is used, and the others are carried out in the same manner as in (a), and the block chain is sequentially extended from the end to produce. Method,
(C) A method of producing each block chain or a part of each block chain by a coupling reaction after polymerizing in a predetermined sequence,
Etc. can be illustrated.

  Living radical polymerization can be performed using a transition metal complex as a catalyst and an organic halogen compound having one or more halogen atoms in the molecule as an initiator.

  Examples of transition metal complexes include dichlorotris (triphenylphosphine) ruthenium or chloroindenylbis (triphenylphosphine) ruthenium, dihydrotetrakis (triphenylphosphine) ruthenium, dicarbonylcyclopentadienylruthenium iodide (II), etc. Ruthenium complex; dicarbonylcyclopentadienyl iron iodide (I), di (triphenylphosphine) iron dichloride, di (tributylamino) iron dichloride, triphenylphosphine iron trichloride, (1-bromo) ethylbenzene-tri Iron complexes such as ethoxyphosphine-iron dibromide; carbonylcyclopentadienyl nickel iodide (II), carbonylcyclopentadienyl nickel bromide (II), carbonylcyclopentadienyl nickel chloride (II), carbonyl Nickel complexes such as nickel (II) iodide and nickel (II) carbonylindenyl bromide; molybdenum (II) tricarbonylcyclopentadienyl molybdenum iodide (II), tricarbonylcyclopentadienyl molybdenum bromide (II), tricarbonylcyclo And molybdenum complexes such as pentadienylmolybdenum chloride (II) and di-Naryl-di (2-dimethylaminomethylphenyl) lithium molybdenum. These transition metal complexes can be used alone or in combination of two or more.

  Organohalogen compounds contain 1 to 4 or more halogen atoms (fluorine, chlorine, bromine, iodine, etc.) and are used as initiators to initiate polymerization by acting with transition metal complexes to generate radical species It is done. Such organic halogen compounds can be used alone or in combination. The organic halogen compound is not particularly limited and various compounds can be used. For example, halogenated hydrocarbons, halogenated esters (halogen-containing esters), halogenated ketones (halogen-containing ketones), sulfonyl halides (halogenated sulfonyl compounds) ) Etc. are included.

  In the living radical polymerization method, a Lewis acid and / or an amine can be used as an activator for promoting radical polymerization by acting on a metal complex.

  Examples of Lewis acids include aluminum alkoxides (aluminum triethoxide, aluminum triisopropoxide, aluminum tris-butoxide, aluminum tri-toxide, etc.), scandium alkoxides (scandium triisopropoxide, etc.), titanium alkoxides (titanium). Tetramethoxide, titanium tetraethoxide, titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra t-butoxide, titanium tetraphenoxide, etc., zirconium alkoxide (zirconium tetraisopropoxide, etc.), tin alkoxide (tin tetraiso Propoxide, etc.).

  The amines are not particularly limited as long as they are nitrogen-containing compounds such as secondary amines, tertiary amines, nitrogen-containing aromatic heterocyclic compounds, etc., but secondary amines and tertiary amines are particularly preferably exemplified. Can do.

As a method for producing a copolymer by the living radical polymerization method, specifically,
[1] For example, after the conversion rate of the first monomer reaches 100%, the second monomer is added to complete the polymerization, and this is repeated to obtain a block copolymer A method of sequentially adding the body,
[2] Even if the conversion rate of the first monomer does not reach 100%, the polymerization is continued by adding the second monomer at the stage where the target degree of polymerization or molecular weight is reached, and random parts are formed between the block chains. To obtain a gradient copolymer in which
[3] Even when the conversion rate of the first monomer does not reach 100%, the reaction is stopped once the target degree of polymerization or molecular weight is reached, the polymer is taken out of the system, and the resulting polymer is A method of obtaining a block copolymer by intermittently advancing copolymerization by adding other monomers as an initiator,
Etc. can be illustrated.

  The polymerization method is not particularly limited, and a conventional method such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization can be adopted, and solution polymerization is particularly preferable. In the case of performing solution polymerization, the solvent is not particularly limited, and a conventional solvent such as an aromatic hydrocarbon (benzene, toluene, xylene, etc.), an alicyclic hydrocarbon (cyclohexane, etc.), an aliphatic hydrocarbon, etc. (Hexane, octane, etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone, etc.), ethers (tetrahydrofuran, dioxane, etc.), esters (ethyl acetate, butyl acetate, etc.), amides (N, N-dimethylformamide, N, N-dimethylacetamide etc.), sulfoxides (dimethylsulfoxide etc.), alcohols (methanol, ethanol etc.), polyhydric alcohol derivatives (ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate etc.) etc. can be used. These solvents can be used alone or in combination of two or more. The polymerization is usually performed in a vacuum or in an atmosphere of an inert gas such as nitrogen or argon, at a temperature of 0 to 200 ° C, preferably 40 to 150 ° C, at normal pressure or under pressure.

  On the other hand, in the living anion polymerization method, alkali metal or organic alkali metal is used as a polymerization initiator, and it is usually −100 to 50 ° C. in an organic solvent under an atmosphere of an inert gas such as vacuum or nitrogen or argon, preferably It can be carried out at -100 to -20 ° C. Examples of the alkali metal include lithium, potassium, sodium, cesium, and the like, and examples of the organic alkali metal include alkylated products, allylated products, arylated products, and the like of the above alkali metals. , N-butyllithium, sec-butyllithium, t-butyllithium, ethyl sodium, lithium biphenyl, lithium naphthalene, lithium triphenyl, sodium naphthalene, α-methylstyrene dianion, 1,1-diphenylhexyllithium, 1,1- Examples thereof include diphenyl-3-methylpentyl lithium.

  Organic solvents used include aromatic hydrocarbons (benzene, toluene, xylene, etc.), aliphatic hydrocarbons (hexane, octane, etc.), alicyclic hydrocarbons (cyclohexane, cyclopentane, etc.), ketones (acetone) , Methyl ethyl ketone, cyclohexanone, etc.), ethers (tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc.), anisole, hexamethylphosphoramide, and other organic solvents usually used. For the purpose of controlling the copolymerization reaction, known additives such as alkali metal salts and / or alkaline earth metal salts of mineral acids such as lithium chloride may be used.

  In addition, when using a living anion polymerization method and using a compound having an active hydrogen such as a hydroxyl group or a carboxyl group in the molecule, the active hydrogen is protected by a known protective reaction such as silylation, acetalization or BOC formation. The polymer can be produced by subjecting it to a polymerization reaction and performing a deprotection reaction with an acid, an alkali or the like after the polymerization.

  Tracking of the copolymerization reaction process and confirmation of the completion of the reaction can be easily performed by gas chromatography, liquid chromatography, gel permeation chromatography, membrane osmotic pressure method, NMR or the like. After completion of the copolymerization reaction, a copolymer can be obtained by applying a normal separation and purification method such as column purification, or filtering and drying a polymer component deposited in, for example, water or a poor solvent. Can do.

1-2) Multibranched copolymer The multibranched copolymer used in the present invention has the formula (III)
X [B-Y (A) _n1 ] _n2 (III)
[Where,
X represents an organic group having 3 or more bonds.
A is the formula (I)

Wherein R ^{1 to} R ⁵ and m are the same as defined above, and the formula (II)

(Wherein R ^{6 to} R ⁹ are the same as defined above), and represents a random copolymer having a repeating unit.
B is the formula (IV)

(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). Represents a polymer containing units.
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.
n1 represents 1 or 2, and n2 represents any integer of 2 to 16. It is a polymer represented by

Below, each part in the said Formula is demonstrated.
(X)
In the 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 “alkylene group, alkenylene group, alkynylene group, phenylene group or two or more groups thereof” are —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 formula, A represents the formula (I)

(Wherein R ^{1 to} R ⁵ and m are the same as defined above), and the formula (II)

(Wherein R ^{6 to} R ⁹ are the same as defined above), and a plurality of A may be the same or different.
In addition to the above-described repeating units, A may have other repeating units that can be copolymerized therewith.
Examples of such a polymerizable monomer that gives another copolymerizable repeating unit include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, -Conjugated dienes such as 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 ⁹ and m in the repeating units (I) and (II) exemplify the same groups as R ^{1 to} R ⁹ and m in the repeating units (I) and (II) in the linear copolymer. can do.

The degree of polymerization of the repeating units (I) and (II) in the random copolymer is preferably 30 to 2,000, and particularly preferably 50 to 1,000.
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 (VII) is preferably 30 to 60% by weight.

(Wherein R ^4a , R ^4b, R ⁵ and m are the same as defined above.)

(B)
B is the formula (IV)

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 An alkyl group 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, etc. 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-heptynyl group, 1-octynyl group, 1-decynyl group and the like alkynyl groups; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, etc. Examples thereof include cycloalkyl groups; aryl groups such as phenyl groups and naphthyl groups; arylalkyl groups such as benzyl groups and phenethyl groups.
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, benzoimidazolyl, , Cinnolinyl, indazolyl, indolizinyl, phthalazinyl, pyridazinyl, triazinyl, isoindolyl, pteridinyl, purinyl, oxadiazolyl, triazolyl, thiadiazolyl, thiadiazolyl, furazanyl, benzofurazanyl, benzothiophenyl, benzothiazolyl, benzoxazolyl, quinazolinyl, quinazolinyl, quinazolinyl It is done.
The degree of polymerization of the repeating unit (IV) 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 multibranched copolymer 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 (VIII), (IX), or (X). .

In Formula (VIII), T represents a divalent electron-withdrawing group, and 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 (VIII), (IX) and (X), the position that can have an active halogen atom is a carbon atom to which ** is attached. It means that an active halogen atom was bonded to the carbon atom of ** of Y.

In the formula (IX), 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 (X), 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. R ²⁶ 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. Represents.
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 Examples include carbonyl group, aryloxycarbonyl group such as naphthyloxycarbonyl group, etc.
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 (VIII), 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 copolymer)
Examples of the multi-branched copolymer used in 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 copolymer of the present invention, those represented by the following formula (XI) are preferable.

Wherein, Z is represents a (CH ₂₎ q or p- phenylene, q represents an integer of 0 to 3, each R is independently hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted 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 multi-branched copolymer of the present invention by GPC-MALLS method is in the range of 10,000 to 2,000,000, preferably 50,000 to 1,000,000. This multi-branched copolymer is a polymer having a controlled molecular weight.

(Manufacturing method of multi-branched copolymer)
The production method of the multi-branched copolymer used in the present invention can be produced in the same manner as the method described in International Publication No. 2006/016665 pamphlet, but briefly described as follows.
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 ′} , X ′, B ′ and n2 ′ are the same as X, B and n2 in the formula X [BY (A) _n1 ] _n2 , respectively. is there.
Y ′ represents a functional group represented by the following formula (XII), formula (XIII) or formula (XIV).

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

The polymerization method of the compound represented by the formula X ′ [B′-Y ′] _{n2 ′} and the compound having a polymerizable unsaturated bond may be represented by the formula X ′ [B′-Y ′] _{n2 ′} . A monomer solution containing a compound having a polymerizable unsaturated bond, another monomer that can be copolymerized if desired, and a reaction solvent is charged in a reaction vessel all at once or during the reaction, and nitrogen, argon, etc. Radical polymerization method in which polymerization is performed using a commercially available radical initiator (azo-based initiator, peroxide, etc.) under an active gas atmosphere as necessary; represented by the formula X ′ [B′-Y ′] _{n2 ′} A monomer solution containing a compound having a polymerizable unsaturated bond, another monomer that can be copolymerized if desired, and a reaction solvent is charged in a reaction vessel all at once or during the reaction, and nitrogen, argon, etc. While stirring in an active gas atmosphere, an anionic polymerization initiator is added. Anionic polymerization performs beat 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) a living radical polymerization method in which a 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) a stable radical initiator. A living radical polymerization method using Among these, the living radical polymerization method (A) is preferable from the viewpoint of obtaining the target multi-branched copolymer 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.

  Among these, since a narrower-dispersed multi-branched copolymer can be obtained, the method (3) for 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.

2) Electrolyte salt The electrolyte salt used in the present invention is not particularly limited, and an electrolyte salt containing an ion that is desired to be a carrier by charge may be used, but in a polymer solid electrolyte obtained by curing. It is desirable that the dissociation constant is large, an alkali metal salt, a quaternary ammonium salt such as (CH ₃ ) ₄ NBF ₆ , a quaternary phosphonium salt such as (CH ₃ ) ₄ PBF ₆ , a transition metal salt such as AgClO ₄ or hydrochloric acid Protonic acids such as perchloric acid and borohydrofluoric acid can be used, and alkali metal salts, quaternary ammonium salts, quaternary phosphonium salts or transition metal salts are preferably used.

Specific examples of the electrolyte salt that can be used include, for example, LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) ₃ , LiC (CH ₃ ) (CF ₃ SO ₂ ) ₂ , LiCH (CF ₃ SO ₂ ) ₂ , LiCH ₂ (CF ₃ SO ₂ ), LiC ₂ F ₅ SO ₃ , LiN (C ₂ F ₅ SO ₂ ) ₂ , LiN (CF ₃ SO ₂ ), LiB (CF ₃ SO ₂ ) _{2, LiPF 6, LiSbF 6,} LiClO 4, 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 It can be exemplified known alkali metal salts of _2, and these electrolyte salts may be used singly or two or more, among them lithium salts are preferable.
The addition amount of these electrolyte salts is 0.005-80 mol% with respect to the alkylene oxide unit in a copolymer, Preferably it is the range of 0.01-50 mol%.

3) Polymer electrolyte The above-mentioned copolymer and electrolyte salt can be produced by mixing (compositing) other components as required, for example, an inorganic filler, but the mixing method is not particularly limited. , A method of dissolving a copolymer and an electrolyte salt (and other components) in an appropriate solvent such as tetrahydrofuran, methyl ethyl ketone, acetonitrile, ethanol and dimethylformamide, a copolymer and an electrolyte salt (and other components) at room temperature or heating The method of mixing mechanically below is mentioned.

2 Nonwoven fabric Examples of the material of the nonwoven fabric include organic fibers and inorganic fibers.
Examples of organic fibers include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyphenylene sulfide, polysulfone, polyethersulfone, polyvinylidene fluoride, polytetrafluoroethylene, polyamide, polyimide, acrylic, nylon, Derivatives such as rayon and cellulose; or a mixture thereof are preferably used.
Examples of the inorganic fiber include glass, metal, metal oxide, ceramics, and carbon.
In particular, polyester (polyethylene terephthalate) and polyolefin (single fiber or composite fiber made of polyethylene or polypropylene, or core-sheath fiber made of polypropylene as a core and polyethylene as a sheath) are desirable.
Examples of the form of the nonwoven fabric include, but are not limited to, various dry nonwoven fabrics such as spunbond, melt blow, spunlace, needle punch, card or airlay, wet nonwoven fabric, or woven fabric produced by weaving warp and weft. It is not something.
The thickness of the nonwoven fabric is preferably 0.5 μm to 100 μm. More preferably, it is 10-50 micrometers. If the thickness is less than 0.5 μm, the strength is weak, and it cannot be combined with the solid polymer electrolyte to ensure the strength. On the other hand, when the thickness is larger than 100 μm, the thickness of the non-woven composite polymer solid electrolyte sheet combined with the polymer solid electrolyte is also increased, and the resistance between the battery electrodes is increased because the distance between the battery electrodes is too wide. Invite.
The air permeability (fragile type) indicating the porosity of the nonwoven fabric is preferably 1 cm ³ / cm ² · s to 400 cm ³ / cm ² · s. More preferably from ^{5cm 3 / cm 2 · s~300cm 3} / cm 2 · s.
If the fragile air permeability of the nonwoven fabric is less than 1 cm ³ / cm ² · s, a sufficient amount of solid electrolyte cannot be present between the nonwoven fabric fibers, leading to a decrease in ionic conductivity. Moreover, when larger than 400 cm < ³ > / cm < ² > * s, since there is little entanglement of nonwoven fabric fibers, intensity | strength falls.

3 Nonwoven fabric composite polymer solid electrolyte sheet The nonwoven fabric composite polymer solid electrolyte sheet of the present invention can be produced by supporting the above polymer electrolyte on a nonwoven fabric.
The method for supporting the polymer electrolyte on the nonwoven fabric can be carried out by a known method. For example, a polymer electrolyte-containing solution in which the polymer electrolyte is dissolved or dispersed in a solvent is applied to the nonwoven fabric under normal pressure or It can be carried out by heating and drying under reduced pressure. The coating method is not particularly limited. For example, roll coater method, gravure coater method, knife coater method, kiss coater method, die coater method, screen coating method, doctor blade method, bar coating method, curtain coater method, spin coating Various coating means such as a method, a dipping method, a casting method, a spray coating method, and an extrusion coater method can be mentioned.

The present invention will be described by way of examples, but the technical scope of the present invention is not limited thereby.
In the following, “PME” is methoxypolyethylene glycol monomethacrylate, “DPE- (m-OTBDMS) ₂ ” is 1,1-bis-[(3-tert-butyldimethylsilyloxy) methylphenyl] -ethylene, “TBAF” Means tetrabutylammonium fluoride.

1 Production of Copolymer [Reference Production Example 1] Block copolymer Blemmer PME-1000 (manufactured by NOF Corporation) 840.0 g (754.5 mmol) and toluene 1960 g were collected in a flask and mixed uniformly. I worried. To this mixed solution, 1.4 g (1.5 mmol) of dichlorotris (triphenylphosphine) ruthenium, 0.78 g (6.0 mmol) of di-n-butylamine, and 0.57 g (3.0 mmol) of 2,2-dichloroacetophenone were added. added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction. 67 hours after the start of the polymerization reaction, the reaction solution was cooled to 0 ° C. to stop the polymerization reaction. When the conversion rate was calculated | required from NMR, the polymerization rate of PME-1000 was 81%. The reaction solution was applied to a column to remove the metal complex and unreacted monomers. The solvent was distilled off until the polymer concentration reached 40%, and the resulting solution was used as such for the next reaction. A part of the solution was weighed and the yield was determined by drying under reduced pressure. The recovery rate relative to the theoretical amount determined from the conversion rate was 90%. Moreover, it was Mw = 218,800 when the molecular weight was calculated | required by GPC-MALLS.
To the solution obtained previously, 282.5 g (2.7 mol) of styrene and 1154.1 g of toluene were added, mixed uniformly, and deaerated. To this mixed solution, 0.73 g (5.7 mmol) of di-n-butylamine and 1.4 g (1.5 mmol) of dichlorotris (triphenylphosphine) ruthenium were added, and the polymerization reaction was started by heating to 100 ° C. It was. 71 hours after the start of the polymerization reaction, the reaction solution was cooled to 0 ° C. to stop the polymerization reaction. When the conversion rate was determined by NMR, the polymerization rate of styrene was 30%. The reaction solution was applied to the column to remove the metal complex. The viscous residue obtained by concentrating the solvent under reduced pressure was dried under reduced pressure at 60 ° C. for 5 hours to obtain 696.4 g of a block polymer. The recovery rate with respect to the theoretical amount determined from the conversion rate was 98%. Moreover, it was Mw = 252,200 when molecular weight was calculated | required by GPC-MALLS.

[Reference Production Example 2] Multibranched copolymer 1) Synthesis of arm In a nitrogen-substituted 2000 mL four-necked flask, 113 g of dehydrated tetrahydrofuran (hereinafter abbreviated as THF), 1020 g of dehydrated toluene, DPE- (m-OTBDMS) ₂ 13 .75 g (29.3 mmol) was added and the reaction system was kept at −40 ° C. with stirring. 11.35 g (26.7 mmol) of n-butyllithium / hexane 1.6 mol / L solution (hereinafter abbreviated as NBL) was added to the reaction system and stirred for 30 minutes. Thereafter, 200 g (1920.3 mmol) of styrene was added to the reaction system for polymerization. Sampling was performed 20 minutes after the completion of the dropping, and the completion of polymerization was confirmed by gas chromatography (hereinafter abbreviated as GC).
When this polymer solution was analyzed by gel filtration chromatography (hereinafter abbreviated as GPC), it was a unimodal polymer having a molecular weight Mn = 9400 and a dispersity Mw / Mn = 1.49.

2) Starization reaction 1.56 g (2.5 mmol) of 1,1,2,2-tetrakis- (4-ethoxycarbonylphenyl) ethane dissolved in 25 ml of dehydrated THF was added to the reaction system, and the reaction was continued for 30 minutes. The reaction was stopped using methanol. The polymer solution was poured into a large amount of methanol to precipitate a polymer, filtered and washed, and then dried under vacuum at 50 ° C. for 5 hours to obtain 205 g of a white powdery polymer (yield 97%).
By using preparative GPC, an excess amount of the arm polymer was removed to obtain a white powdery star polymer. When this polymer was analyzed by GPC, it was a unimodal polymer having a molecular weight Mn = 46,800 and a dispersity Mw / Mn = 1.02. Further, when measured with a multi-angle light scattering detector (hereinafter abbreviated as GPC-MALLS), the molecular weight Mw was 81,100 and the degree of dispersion Mw / Mn was 1.013.

3) Functional group conversion [OTBDMS group ⇒ OH group]
To a 2000 mL flask purged with nitrogen, 1500 mL of dehydrated THF, 200 g of 8 arm star polymer, and 100 mL of TBAF (1.0 M in THF) were added and stirred overnight at room temperature. The solvent was concentrated to half, and this solution was poured into a large amount of methanol to precipitate a polymer. After filtration and washing, the polymer was dried at 50 ° C. for 5 hours under vacuum to obtain 195 g of a white powdery polymer (yield 98%) )

4) Functional group conversion [OH group ⇒ OBiB group]
To a 2000 mL four-necked flask purged with nitrogen, 1200 ml of dehydrated THF, 190 g (2.3 mmol) of 8 arm star polymer (OH group) and 5.70 g (56.3 mmol) of triethylamine were added, and the reaction system was maintained at 0 ° C. with stirring. . To the reaction system, 11.2 g (48.7 mmol) of bromoisobutyryl bromide was gradually added. After completion of the dropwise addition, the mixture was returned to room temperature and stirred overnight. After removing the TEA odorate by filtration, the solvent was concentrated to half, and this solution was poured into a large amount of methanol to precipitate a polymer, followed by filtration and washing. The polymer obtained was subjected to fractional purification with THF / MeOH, reprecipitated with a large amount of MeOH, and then dried at 50 ° C. for 5 hours under vacuum to obtain 140 g of a white powdery polymer (yield 74%). It was.
When this polymer solution was analyzed by GPC, it was a unimodal polymer having a molecular weight Mn = 45,700 and a dispersity Mw / Mn = 1.026. Moreover, it was molecular weight Mw = 82,500 and dispersion degree Mw / Mn = 1.020 when it measured by GPC-MALLS.

5) Living radical polymerization A 100 ml flask was charged with 10.0 g of the previously synthesized star polymer, PME-1009.0 g (8.1 mmol), and 30 g of toluene, and degassed. Dichlorotris (triphenylphosphine) ruthenium 0.5 g (0.5 mmol) was added and dissolved uniformly, then tributylamine 0.4 g (2.2 mmol) was added, and the polymerization reaction was carried out by heating to 80 ° C. Started. Eight hours after the start of the polymerization reaction, the polymerization reaction was stopped by cooling the reaction solution to 0 ° C. When the conversion rate was calculated | required from NMR, the conversion rate of PME-1000 was 75%. The reaction solution was applied to a column to remove the metal complex and unreacted monomers. The solvent was dried under reduced pressure to obtain a viscous material. When this polymer solution was measured by GPC-MALLS, it had a molecular weight Mw = 595,100 and a PEO content of 79.6%.

2. Fabrication of non-woven composite polymer solid electrolyte sheet [Example 1]
The operation was performed in a glow box under an argon atmosphere.
As the nonwoven fabric, a polyethylene terephthalate nonwoven fabric made of polyethylene terephthalate fiber having a basis weight of 7.7 g / m ² , a thickness of 18 μm, and an air permeability of 37 cm ³ / cm ² · s (fragile type) was used.
5.7 g of the MES polymer obtained in Reference Production Example 1 (Mw. 252,000, PEO content 81.7%) was added to 24.3 g of dimethoxyethane solvent and dissolved at room temperature, and the polymer concentration was 18 wt%. Solution was obtained. Next, 1.54 g of LiTFSI (lithium bis (trifluoromethanesulfonyl) imide) as a lithium salt was added and dissolved to obtain a mixed solution. At this time, the molar ratio of Li in the electrolyte salt to ethylene oxide unit (EO) in the polymer, that is, [Li] / [EO] was 0.05.
A dip coat was performed by immersing and pulling up the nonwoven fabric cut into a 10 cm square in the mixed solution spread on the petri dish, and laying on the release film. In order to remove the dimethoxyethane solvent, heating and vacuum drying were performed at 70 ° C. for 1 hour and subsequently at 90 ° C. for 3 hours to obtain a uniform nonwoven fabric composite polymer solid electrolyte sheet (1) having a thickness of 36 μm.

[Example 2]
5.4 g of the MES polymer (Mw. 595,000, PEO content 79.6%) obtained in Reference Production Example 2 was added to 24.3 g of dimethoxyethane solvent and dissolved at room temperature. A uniform nonwoven fabric having a film thickness of 42 μm is obtained by performing the same operation as in Example 1 after adding 1.42 g of LiTFSI and dissolving it so that the [Li] / [EO] ratio is 0.05. A composite polymer solid electrolyte sheet (2) was obtained.

[Comparative Examples 1-5]
A non-woven fabric composite polymer solid electrolyte was prepared in the same manner as in Example 1 except that LiTFSI was added and dissolved in the following polyethylene oxide-based material so that the [Li] / [EO] ratio was 0.05. A sheet was produced.
(Comparative Example 1)
10.3 g of polyethylene glycol (Mw. 1,000) was added to 10.5 g of dimethoxyethane solvent and dissolved at room temperature. After adding 2.08 g of LiTFSI as much as possible to achieve a [Li] / [EO] ratio of 0.05 to obtain a mixed solution, the same operation as in Example 1 was performed to obtain a comparative sample with a film thickness of 36 μm ( 1) was obtained.
(Comparative Example 2)
1.1 g of polyethylene glycol (Mw.20,000) was added to 24.3 g of ethanol solvent and dissolved at room temperature. After 0.24 g of LiTFSI was added and dissolved so that the [Li] / [EO] ratio was 0.05, a mixed solution was obtained, and then the same operation as in Example 1 was performed to make a comparative sample with a film thickness of 27 μm ( 2) was obtained.
(Comparative Example 3)
0.8 g of polyethylene glycol (Mw. 500,000) was added to 27.0 g of an ethanol solvent and dissolved at room temperature. After adding 0.19 g of LiTFSI as much as possible so that the [Li] / [EO] ratio is 0.05 to obtain a mixed solution, the same operation as in Example 1 is performed to perform a comparative example with a film thickness of 22 μm (3 ) A sample was obtained.
(Comparative Example 4)
10.0 g of polyethylene glycol dimethyl ether (Mw. 2,000) was added to 15.3 g of an ethanol solvent and dissolved at room temperature. After adding 2.30 g of LiTFSI as much as possible to obtain a [Li] / [EO] ratio of 0.05 to obtain a mixed solution, the same operation as in Example 1 was performed to make a comparative example sample having a film thickness of 41 μm ( 4) was obtained.
(Comparative Example 5)
Polyethylene glycol methyl ether methacrylate polymer (Mw. 180,000, degree of polymerization of ethylene oxide unit n≈9) 5.0 g was added to 20.2 g of dimethoxyethane solvent and dissolved at room temperature. After 1.30 g of LiTFSI was added and dissolved as much as possible so that the [Li] / [EO] ratio was 0.05, a mixed solution was obtained, and then the same operation as in Example 1 was performed to make a comparative sample with a film thickness of 38 μm ( 5) was obtained.

3 Exam
[1] Confirmation of film forming property The film forming state of the nonwoven fabric composite polymer solid electrolyte sheet was confirmed. After the film formation and drying, the nonwoven fabric composite polymer solid electrolyte sheet was peeled off from the release film substrate, and whether or not a self-supporting film was formed, the film quality, and the presence or absence of the polymer on the release film were confirmed.
In Table 1, the film thickness and film quality of the obtained nonwoven fabric composite polymer solid electrolyte sheet, and the residual polymer on the peelable film for forming a self-supporting film are indicated by ○ ×.
The nonwoven fabric composite polymer solid electrolyte sheet obtained from Examples (1) and (2) was the only one that could form a self-supporting film, had good peelability from the release film used in the production process, and had good adhesion. It was.
None of the samples of the comparative examples satisfy the above-mentioned characteristics.

[2] Sheet film strength Tensile test pieces (100 mm × 25 mm) were produced from the nonwoven fabric composite polymer solid electrolyte sheets (1) and (2) of the examples, and a desktop precision universal at a rate of 200 mm / min at 25 ° C. A tensile test was performed using a testing machine (Autograph AGS-J, Shimadzu Corporation). For the film strength, the breaking force when the test piece broke was used. table. It is shown in 2.
As can be seen from the results in Table 2, the nonwoven fabric composite polymer solid electrolyte sheets (1) and (2) showed higher tensile membrane strength than the nonwoven fabric alone. The effect of combining the polymer solid electrolyte and the nonwoven fabric appears. In particular, the nonwoven fabric composite polymer solid electrolyte sheet (1) showed high membrane strength.

[3] Adhesiveness of sheet About nonwoven fabric composite polymer solid electrolyte sheet (1), (2), 180 degree peeling adhesive strength (JIS Z 0237) with respect to a base material was calculated | required, and it was set as the parameter | index of the adhesiveness of a sheet | seat.
A test piece (250 mm × 25 mm, test piece length in the vertical direction) was prepared and pressure-bonded to the base material to prepare a measurement jig described in JIS Z 0237. The peeling test was performed using a desktop precision universal testing machine (Autograph AGS-J, Shimadzu Corporation) at a speed of 300 mm / min at 25 ° C. For the base material, aluminum foil (film thickness: 18 μm, manufactured by Nippon Foil Co., Ltd.), which is a positive electrode current collector for batteries, and rolled copper foil (film thickness: 18 μm, manufactured by Nippon Foil Co., Ltd.) for negative electrodes for batteries And a PET film (polyethylene terephthalate film, film thickness 100 μm, manufactured by Toray Industries, Inc.).
Table 3 shows the results of measurement of adhesive strength with respect to various substrates.

  As can be seen from the results from Table 3, the non-woven fabric composite polymer solid electrolyte sheets (1) and (2) exhibited good adhesion to various substrates.

[4] Ionic conductivity The ionic conductivity of the nonwoven fabric composite polymer solid electrolyte sheet (1) and (2) was measured.
A measurement cell was assembled by sandwiching a non-woven composite polymer solid electrolyte sheet between platinum electrodes having a diameter of 1 cmφ. The measurement cell was produced in a glove box under an argon atmosphere. The ionic conductivity was 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. Table of results. 2 shows a graph of ionic conductivity in FIG.
As can be seen from the results in Table 4, the non-woven fabric composite polymer solid electrolyte sheet (1) having a film thickness of 36 μm and the non-woven fabric composite polymer solid electrolyte sheet (2) having a film thickness of 42 μm are thin. Nevertheless, it is noted that good ionic conductivity is obtained without causing a short circuit.

[5] Battery test A coin battery was prepared for a lithium secondary battery using the nonwoven fabric composite polymer solid electrolyte sheet (1), and battery operation was evaluated by cyclic voltammetry measurement.
(Preparation of positive electrode)
Lithium iron phosphate, ketjen black, and polyvinylidene fluoride were sufficiently dispersed in N-methyl-2-pyrrolidone at a weight ratio of 80:10:10 to obtain a positive electrode mixture slurry.
Next, the positive electrode mixture slurry is applied onto an aluminum foil (film thickness: 18 μm) of the positive electrode current collector, N-methyl-2-pyrrolidone is removed by heating and vacuum drying, and then compression molding is performed at a constant pressure. A sheet (film thickness 38 μm) was prepared.

(Production of coin battery)
The coin battery was produced in a glow box under an argon atmosphere. The positive electrode sheet, the negative electrode lithium sheet (thickness 250 μm), and the non-woven fabric composite polymer solid electrolyte sheet (1) are punched into a circular shape, and the non-woven composite polymer solid electrolyte sheet is sandwiched between the positive electrode and the negative electrode. A battery was produced.

(Cyclic voltammetry measurement)
After the natural potential (open circuit voltage) of this test cell is stabilized, the natural potential is started, and cyclic voltammetry measurement (CV) is performed in the range of +4.0 V to +2.0 V (vs. Li ^/ Li ⁺ ) at 25 ° C. Measurement) was performed using an automatic polarization system (HSV-110, Hokuto Denko Co., Ltd.). The sweep speed was 10 mV / and a CV curve was obtained. The results are shown in FIG.
As can be seen from the results of FIG. 2, it was confirmed that the battery using the nonwoven fabric composite polymer solid electrolyte sheet (1) operates well without short-circuiting.

Claims (5)

On the nonwoven fabric
(A) 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 2 to 100, and when m is 2 or more, R ^4a and R ^4b may be the same or different. A block chain A having a repeating unit represented by formula (II)

(Wherein R ^{6 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ⁹ represents an aryl group). A block copolymer having B and the formula (III)
Formula X [B-Y (A) _n1 ] _n2 (III)
[Wherein, X represents an organic group having 3 or more bonds. A is the formula (I)

Wherein R ^{1 to} R ⁵ and m are the same as defined above, and the formula (II)

(Wherein R ^{6 to} R ⁹ are the same as defined above), and represents a random copolymer having a repeating unit. B is the formula (IV)

(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). Represents a polymer containing units.
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.
n1 represents 1 or 2, and n2 represents any integer of 2 to 16. A non-woven fabric composite polymer solid electrolyte sheet comprising a polymer electrolyte containing at least one selected from the group consisting of a multi-branched copolymer represented by the formula (B) and an electrolyte salt. The molar ratio ((I) / (II)) of the repeating unit represented by the formula (I) and the repeating unit represented by the formula (II) of the block copolymer is 1/30 to 30/1. The nonwoven fabric composite polymer solid electrolyte sheet according to claim 1, characterized in that The nonwoven fabric composite polymer solid electrolyte sheet according to claim 1 or 2, wherein the block copolymer has a number average molecular weight of 5,000 to 1,000,000 by GPC using polystyrene as a standard. . The degree of polymerization of the repeating units (I) and (II) in the random copolymer of A of the multi-branched copolymer is 30 to 2,000, respectively. The nonwoven fabric composite polymer solid electrolyte sheet as described in 2. The nonwoven fabric composite height according to any one of claims 1 to 4, wherein the multi-branched copolymer has a weight average molecular weight (Mw) by GPC-MALLS method of 10,000 to 2,000,000. Molecular solid electrolyte sheet.