JP2000017017A - Polymeric particles carrying alkali metal salt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve ionic conductivity, by providing a particle having, on its surface, an anionic group contg. a group XIII, XV or XVI element of the Periodic Table, and having a specific particle diameter. SOLUTION: A radically polymerizable monomer such as a monofunctional acrylate deriv. and an α,ω-alkylene diol diacrylate deriv. is subjected to emulsion polymerization or micelle polymerization, together with a surfactant having an anionic group contg. an element selected from groups XIII, XV and XVI of the Periodic Table, in a solvent in which the radically polymerizable monomer is insol. or difficultly soluble, in the presence of a radical polymerization initiator, to form a polymer particle represented by formulae I-IV (wherein M1 is a boron atom or an aluminum atom; M2 is a phosphous atom, an arsenic atom or an antimony atom; L is an alkylene having a halogen; Rn is a halogen, an alkoxy, an alkyl or an arom. group; and (n) is 5 or less) with a mol.wt. of 300-50,000, the particle having, on its surface, an anionic group contg. on element selected from groups XIII, XV and XVI of the Periodic Table, with a particulate diameter of 0.001-1 μm, and carrying an alkali metal salt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to polymer fine particles carrying an alkali metal salt, a method for producing the same, and a sheet-like molded article containing the same. Since the molded body has high cation conductivity, it has performance as a solid electrolyte, and is used as a cation conductor such as an electrolyte layer in a secondary battery.

[0002]

2. Description of the Related Art Ion-conductive solids, that is, solid electrolytes, are useful materials for improving the safety and reliability of chargeable and dischargeable storage batteries (secondary batteries). In other words, solid electrolytes are used for the dangers of liquid electrolytes that have been widely used in the past, such as the strong acidity of aqueous sulfuric acid solutions in lead-acid batteries, which have been widely used as power supplies for automobiles, and the power supplies for mobile phones and notebook computers. Flammability of the organic solvent solution of the lithium ion secondary battery, or a material that has the potential to solve problems common to liquid electrolytes, such as liquid leakage and jetting disaster at the time of pressurization at once. it can. Therefore,
Solid electrolytes with these characteristics can be widely used with high reliability in applications that require large-capacity charging and discharging in response to global environmental protection and energy saving requirements on recent global scales, such as electric vehicles and surplus power storage facilities. The development of a solid electrolyte that is an indispensable material and has high ionic conductivity is of great significance. On the other hand, a so-called polymer gel electrolyte has been studied as a means for improving the above-mentioned disadvantages of the liquid electrolyte. In this method, a gel is formed by combining a liquid electrolyte and a polymer having a strong interaction with the polymer (cross-linking is performed if necessary) to eliminate free liquid.

[0003]

However, since the gel volume may expand and contract due to a phase transition of the gel due to a change in temperature or pressure, there is a possibility that a free liquid may be generated depending on the use conditions. I have a problem. For lithium ion secondary batteries, flame-retardant salts (so-called molten salts) that are liquid at room temperature or higher have been studied as liquid electrolytes that do not use flammable organic solvents. However, in this case, since anions also have mobility, there is an essential disadvantage that the transport number of lithium ions is relatively reduced.

[0004] Conventional solid electrolytes have been developed mainly from two viewpoints: the use of an amorphous organic polymer matrix for dissolving the electrolyte and the use of an ion-conductive inorganic solid. As an example, dissolving a lithium salt such as lithium boron tetrafluoride or lithium perchlorate in a polymer (polyalkylene oxide) having an alkylene oxide such as ethylene oxide or propylene oxide as a monomer has been actively studied. This is based on the principle that lithium ions move by taking advantage of the coordination ability of a polyalkylene oxide, particularly a polyethylene oxide structure to lithium ions, and excellent mobility at a temperature higher than the glass transition point of the polymer chain. I have. However, coordination of the polymer chain to lithium ions is indispensable, and it is difficult to move as free lithium ions without coordination, so that the ionic conductivity has remained at most on the order of 0.01 mS / cm.

On the other hand, as an example, see, for example,
No. 6828, LiPO ₄ —Li ₂ S—
Inorganic glasses such as SiS ₂ have recently been reported. This is a substance having a pathway for moving free lithium ions without coordination, and has a high ionic conductivity of several mS / cm in a bulk state. However, in practice, since it is necessary to compression-mold a fine powder to form a sheet, the ionic conductivity is often less than 1 mS / cm because the contact between the fine powders is not always ideal. Since the toughness (flexibility) of the sheet-like molded product is extremely low, it is necessary to form a composite with a polymer having rubber elasticity. In such a case, there is a disadvantage that the ionic conductivity is further reduced. The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a novel material which has a high ionic conductivity itself and can suppress a decrease in ionic conductivity even when molded, and which is particularly useful as a solid electrolyte.

[0006]

Means for Solving the Problems To achieve the above object, the present inventors have taken the basic idea of positively utilizing the surface of fine particles as an ion transfer path, and have systematically studied the synthesis of submicron particles. As a result of the study, it was found that polymer fine particles carrying alkali metal salts, that is, polymer fine particles with a large number of large anionic groups bonded to the surface, were neutralized with alkali metal cations. As a result, they have found that it is possible to greatly improve the disadvantages of the conventional solid electrolyte, and have completed the present invention. That is, the gist of the present invention is that the periodic tables 13, 15, and 16
Polymer fine particles having an anionic group containing an element selected from the group consisting of groups on the surface of the fine particles and supporting an alkali metal salt having a fine particle diameter of 0.001 to 1 μm.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. (Chemical Structure of Polymer Fine Particles) The polymer fine particles used for the polymer fine particles carrying the alkali metal salt of the present invention have an arbitrary polymer structure, and the elements constituting the polymer structure are not particularly limited. This is because the effect of the present invention is mainly caused by a large number of alkali metal salts bonded to the surface of the polymer fine particles, and the influence of the structure inside the polymer fine particles is small. Examples of the polymer structure include a) a compound obtained by polyaddition such as a radical addition reaction or a Michael addition reaction, b) a compound obtained by ring-opening polymerization, and c) a compound obtained by polycondensation.

Examples of the polymer structure falling under the category a) include acrylic resins such as polymethyl methacrylate and polyethyl acrylate, polystyrene, and styrene.
Styrene resins such as maleic anhydride copolymer, styrene-methyl methacrylate copolymer, or styrene-acrylonitrile copolymer, and polypropylene obtained by repeating Michael addition of amine to acrylonitrile and reduction of nitrile group to amino group And an imine structure.

Examples of the polymer structure falling under the category b) include polycyclic ethers such as polyethylene oxide, polypropylene oxide, polybutylene oxide and polytetrahydrofuran, polybutyrolactone,
Examples include polylactones such as polycaprolactone, polylactams such as polycaprolactam (nylon 6), polycyclic carbonates such as polyethylene carbonate, polypropylene carbonate, and a ring-opening polymer of a cyclic oligomer of bisphenol A, and the like.

C) Examples of the polymer structure by polycondensation include polyhexamethylene adipamide (nylon 66),
A polyamide such as a polyamide obtained from terephthalic acid and / or isophthalic acid and hexamethylenediamine; and one or more bisphenols (for example, bisphenol A) which may contain a polyhydric phenol as a copolymerization component; Aromatic polycarbonates and poly (3,5) produced by reaction with carbonates such as alkyl carbonates, bisaryl carbonates, phosgene, etc.
-Dihydroxybenzoic acid), polyalkylene phthalates such as polyethylene terephthalate and polybutylene terephthalate, polyalkylene naphthalates such as polyethylene naphthalate and polybutylene naphthalate, poly [2,2-bis (hydroxy Methyl) propionic acid], poly (3,5-dihydroxybenzyl alcohol)
Aromatic polyethers such as polymers in which aromatic residues such as polybenzyl ethers and benzene rings are bonded through ether bonds, and aromatic residues such as polymers in which benzene rings are bonded through thioether bonds And other metal oxide polymers containing silica or titania composition obtained by polycondensation of an alkoxymetalate such as tetraethoxy orthosilicate or tetraethoxy orthotitanate. Are also mentioned.

[0011] These optional polymer structures may be mixed in a single fine particle, or different kinds of fine particles may be mixed and present. Preferable examples of the polymer structure include acrylic resins, styrene resins, polyesters such as poly (3,5-dihydroxybenzoic acid) and poly [2,2-bis (hydroxymethyl) propionic acid]; Examples thereof include polybenzyl ethers such as poly (3,5-dihydroxybenzyl alcohol) and a polypropylene imine structure. Among them, acrylic resins, styrene resins, poly (3,5-dihydroxybenzoic acid) and poly [2,2 -Bis (hydroxymethyl) propionic acid], polybenzyl ethers such as poly (3,5-dihydroxybenzyl alcohol), and a polypropyleneimine structure.

(Form of Polymer Fine Particles) The size of the polymer fine particles is in the range of 0.001 to 1 μm in diameter. As described later, it may be preferable to use a single molecule of a hyperbranched polymer represented by a dendrimer structure as the polymer fine particles of the present invention. The diameter ranges from 0.001 μm to 0.1 μm.
020 μm, more preferably 0.02 μm in terms of ion conductivity.
02 μm to 0.015 μm, more preferably 0.003
μm to 0.010 μm, most preferably 0.003 μm
０．００0.008 μm. On the other hand, the diameter is 0.020 μm
The polymer fine particles having a size in the range of 1 to 1 μm are suitably produced by emulsion polymerization or micelle polymerization, as described later.
0.8 μm, more preferably 0.04 μm to 0.6 μm
m, more preferably 0.06 μm to 0.5 μm, and most preferably 0.07 μm to 0.4 μm. The particle size distribution of the polymer fine particles is not particularly limited, but those having a median value of the particle size distribution in the above range are preferable.

The hyperbranched polymer will be described below. Here, the hyperbranch (Hyperbranch) is a dendritic branch, and specifically, Newkome,
G. FIG. R. , Et al. , “Dendritic Mo
resources: Concepts, Synthesi
s, Perspectives "; VCH Verla
gsgesellschaft mbH (Wein
heim, Germany, 1996), Hawke.
r, C.I. J. , Et al; Chem. Soc. ,
Chem. Commun. , 1990, p. 1010,
Tomalia, D .; A. Angew., Et al;
Chem. Int. Ed. Engl. , 29, 138
Page (1990), Hawker, C .; J. , Et a
l; Am. Chem. Soc. , 112, 763
8 (1990); Frechet, J .; M. J. ; S
Science, 263, 1710 (1994), or Masaaki Kakimoto; Chemistry, 50, 608 (1995).
And the like, represented by the dendrimer structure described in detail in the literature.

[0014] One hyperbranched structure has one focal point. Here, the focal point is, as schematically shown in FIG. 1, the starting point of the dendritic branch, that is, the last point when the molecular chain is reversed in the direction of convergence of the branch from an arbitrary branch end of the dendritic structure. Means the branch point. In the hyperbranched polymer of the present invention, the number of branch points is not limited.

It is known that hyperbranched polymers, particularly those having a completely regular branched structure called a dendrimer, become spherical polymers because the branch ends rapidly become crowded with an increase in molecular weight. . Therefore, such a spherical molecule is not used as a concept of a fine particle of a molecular aggregate such as, for example, emulsion polymerization fine particles, but a single molecule is used as a concept of a polymer fine particle of the present invention. The diameter of a dendrimer molecule is controlled by its generation number (see FIG. 1).
Since it usually falls within the range of about 0.001 to 0.02 μm,
Such a dendrimer molecule is most suitable as a polymer fine particle used in the present invention by itself.

The dendrimer synthesis can be roughly classified into Div
rgent method (a method of constructing a molecule from the center of a dendrimer globular molecule, that is, a focal point outward) and Convergent method (a method of first synthesizing a structural unit at a branch end of a dendrimer and sequentially linking them. To obtain a polymer fine particle used in the present invention. However, any method may be used to obtain polymer fine particles used in the present invention. In many respects, the former is preferable.

Although the molecular weight and the branched terminal groups (mainly present on the surface of the spherical molecule) can be almost completely controlled by the dendrimer synthesis, the preferable molecular weight range for the obtained molecular size is usually 300 to 50,000, more preferably 500 to 500. ~ 40000, more preferably 700 ~ 30
000, most preferably from 1,000 to 20,000.
The branched terminal group will be described later.

(Structural Example of Hyperbranched Polymer) Examples of the structure of the hyperbranched polymer that can be used in the present invention include the above-mentioned Newko.
me, G. R. Et al., The structures described in the companion book, for example, B
uhleier, E .; , Et al. ; Synthesi
s, 1978, p. 155, or de Braba
nder-van den Berg, E .; M. M. ,
et al. Angew. Chem. Int. Ed.
Engl. 32, p. 1308 (1993), the polypropylene imine structure, Hawker,
C. J. , Et al; Chem. Soc. , Che
m. Commun. , 1990, p. 1010, or Hawker, C .; J. , Et al; Am. C
hem. Soc. 112, 7638 (1990).
Hawk, polybenzyl ether structure reported in
er, C.E. J. , Et al; Am. Chem. S
oc. , 113, p. 4585 (1991), the aromatic polyester structure, Malmstrom,
E. FIG. , Et al. Macromolecules,
28, page 1698 (1995), the poly [2,2-bis (hydroxymethyl) propionic acid] structure, Morikawa, A .; , Et al. ; Poly
mer J .; , 24, p. 573 (1992), by Roovers, J. et al. ,
et al. Polym. Preprints, 33
Vol., P. 182 (1992). S. , Et al. ; M
Acromolecules, 24, 5893 (1
991), the polyphenylacetylene structure described in Newkome, G .; R. , Et al. J .; O
rg. Chem. , 50, p. 2003 (1985).
a, D. A. et al; Angew. Chem. In
t. Ed. Engl. , 29, 138 (1990)
Polyamidoamine structure reported in
Yaraman, M .; J. et al. Am. Chem. So
c. , 120, 12996 (1998). Among them, from the viewpoint of easiness of synthesis and stability, among them, the above-mentioned polypropylene imine structure, the above-mentioned polybenzyl ether structure, and the above-mentioned aromatic polyester structure Or the above-mentioned aliphatic polyether structure is more preferable, and the above-mentioned polypropylene imine structure (see the following formula (5)) is most preferable from the viewpoint of structural stability.

[0019]

Embedded image

(Anionic group) The polymer fine particles carrying the alkali metal salt of the present invention are prepared by removing an element belonging to any one of the groups 13, 15 and 16 of the periodic table, which is bonded to the surface of the polymer fine particles as the base. It has a contained anionic group. The polymer fine particles supporting the alkali metal salt referred to here are 1
It means that at least an alkali metal salt is bonded to the surface of one fine particle. When utilization as a solid electrolyte is considered, the higher the surface density of the alkali metal salt carried on the surface of the fine particles, the better. Supporting such an anionic group on the surface of the fine particles is the core of the present invention.
Such loading may be achieved by chemical bonding on the surface of the fine particles or by dissolution in a polymer constituting the fine particles (for example, dissolution of the hydrophobic terminal of a non-reactive surfactant in the emulsion polymerized fine particles).

The first reason for using the above-mentioned anionic group is, for example, a small cation (so-called Hard-s) from the viewpoint of providing an excellent solid electrolyte which is an object of the present invention.
According to the offacid / base theory, it is to prepare a large anion group (“soft” anion) for lithium ion which is “hard” cation). In other words, the use of "soft" anions, which have the property of relatively loosely binding to "hard" cations such as lithium ions, which are important as charge carriers in the solid electrolyte, allows the cations in the solid electrolyte to be used. Is to increase the mobility of the vehicle. The second reason is that by immobilizing anions on the surface of the fine particles, substantially only cations can be used as charge carriers in the solid electrolyte, and the transport number of the cations is extremely limited. It can be increased up to.

Preferable examples of such an anionic group include a boron atom (B), a nitrogen atom (N),
A compound having any of an aluminum atom (Al), a phosphorus atom (P), an arsenic atom (As), and an antimony atom (Sb), for example, a compound corresponding to any of the following general formulas (1) to (4) Is shown. However, in the general formulas (1) to (4), M ¹ is a boron atom or an aluminum atom, M ² is a phosphorus atom, an arsenic atom, or an antimony atom, L is an alkylene group having a halogen atom, R is
ⁿ (n is a natural number of 5 or less) independently represents a halogen atom, an alkoxy group, an alkyl group, or an aromatic group.

[0023]

Embedded image

More specifically, BF ₃ ⁻ , BCl ₃ ⁻ ,
Those having a boron atom (B) as a center of negative charge, such as structures represented by the following general formulas (6) to (11):
₃ ^-, AlCl ₃ ^-, to the following general formula (12) to (1
A) having an aluminum atom (Al) as a negative charge center, such as the structure represented by 7) (however, in the following general formulas (6) to (17), R ′ represents an arbitrary alkyl group or an aromatic group; Specifically, a methyl group, an ethyl group, n-
Alkyl groups such as propyl group, isopropyl group, n-butyl group, isobutyl group and tert-butyl group;
-Trifluoroethyl group, 2,2,2-trichloroethyl group, 2,2,3,3,3-pentafluoro-n-propyl group, 2,2,3,3,4,4,4-n- Halogenated alkyl group such as heptafluorobutyl group, phenyl group,
Examples thereof include an aromatic group such as a 4-methylphenyl group and a naphthyl group, and a halogenated aromatic group such as a pentafluorophenyl group and a pentachlorophenyl group. Among them, a 2,2,2-trifluoroethyl group and a 2,2 An alkyl group having a fluorine atom such as a 3,3,3-pentafluoro-n-propyl group, and an aromatic group having a fluorine atom such as a pentafluorophenyl group are preferable),

[0025]

Embedded image B (OR ′) ⁻ (6) BF (OR ′) ₂ ⁻ (7) BF ₂ (OR ′) ⁻ (8) B (R ′) ₃ ⁻ (9) BF (R ′) ₂ ⁻ (10) BF ₂ (R ′) ⁻ (11) Al (OR ′) ₃ ⁻ (12) AlF (OR ′) ₂ ⁻ (13) AlF ₂ (OR ′) ⁻ (14) Al (R ′) ₃ ⁻ (15) AlF (R ') 2 - (16) AlF 2 (R') - (17)

In the general formula (3), R ¹ is an alkyl group having a fluorine atom such as a perfluoroalkyl group such as a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group or a nonafluorobutyl group, or pentafluorophenyl. Nitrogen atom (N) such as sulfonamide anion which is an aromatic group having a fluorine atom such as a group
Having, as a negative charge center, PF ₅ ⁻ , P (OCH
₂ CF _{3) 5} ^- having a negative charge around the phosphorus atom (P), such ^{_{as, AsF 5 -, As (OCH}} 2 CF 3) 5 -
Having an arsenic atom (As) as a center of negative charge,
Examples include those having an antimony atom (Sb) as a negative charge center, such as SbF ₅ ⁻ and Sb (OCH ₂ CF ₃ ) ₅ ⁻ .

Of these, ease of synthesis, stability, and safety
Preferred from the point of totality is BF_Three ^-, B (OCH_TwoCF
_Three)_Three ^-, B (OCH_TwoCF_TwoCF_Three)_Three ^-Etc. Boron
Having an atom as a center of negative charge, AlF_Three ^-, Al
(OCH_TwoCF_Three)_Three ^-, Al (OCH_TwoCF_TwoC
F_Three)_Three ^-With aluminum atom as the center of negative charge
, N (SO_TwoCF_Three)^-, N (SO_TwoCF_TwoC
F_Three)^-Having a nitrogen atom as a center of negative charge,
PF_Five ^-, P (OCH_TwoCF_Three)_Five ^-, P (OCH _TwoC
F_TwoCF_Three)_Five ^-With phosphorus atom as center of negative charge
And N (SO_TwoCF_Three)^-, N (S
O_TwoCF_TwoCF_Three)^-With nitrogen atom as center of negative charge
Are most preferred.

(Method for Producing Polymer Fine Particles) The method for producing polymer fine particles used for the polymer fine particles carrying the alkali metal salt of the present invention is not particularly limited, and physical actions such as pulverization and classification of the polymer particles. Although a production method by is also possible, as a suitable method for controlling the size of the fine particles,
Examples include a method for synthesizing a hyperbranched polymer represented by the above-mentioned dendrimer, and emulsion polymerization or micelle polymerization.

(Emulsion Polymerization or Micellar Polymerization) Emulsion polymerization or micelle polymerization may be mentioned as a preferable method for producing the polymer fine particles used in the polyalkali metal salt of the polymer fine particles of the present invention. Emulsion polymerization in the present invention refers to a radical polymerizable monomer, a surfactant, a solvent in which the monomer is insoluble or hardly soluble, and a radical initiator.
A polymerization form with one element, if necessary, a crosslinking agent,
Optional additives such as a plasticizer, a heat stabilizer, an antioxidant, an ultraviolet absorber, and an inorganic filler may be allowed to coexist.

The radically polymerizable monomers used in the emulsion polymerization include the above-mentioned monofunctional acrylate derivatives, α,
ω-alkylene diol diacrylate derivatives, polyalkylene glycol diacrylate derivatives, α, ω-polyester diol diacrylate derivatives, polyfunctional acrylate derivatives, acrylic acid derivatives, α, β-unsaturated dicarboxylic acids, styrene derivatives, vinyl esters, Examples include allyl esters, vinyl ethers, allyl ethers, unsaturated ketones, and aliphatic olefins. A plurality of these monomers may be used at the same time.

The surfactant used in the emulsion polymerization is not particularly limited, but preferred examples include the following. A) As the anionic surfactant, a fatty acid salt represented by the following general formula (18), an aliphatic sulfonate represented by the following general formula (19), and an alkylbenzene sulfone represented by the following general formula (20) And alkylnaphthalenesulfonic acid salts represented by the following general formula (21). As anionic surfactants suitable for the present invention having reactivity, lithium salts of ω-methacryloyloxyundecanesulfonic acid, also sodium salts, lithium salts of ω-crotonoioxyundecanesulfonic acid, also sodium salts, dodecylallyl Examples thereof include lithium salts of sulfosuccinic acid and sodium salts thereof (for example, Eleminol JS-2 or the like supplied by Sanyo Chemical Co., Ltd., provided that Eleminol is a registered trademark).

[0032]

Embedded image R-COOM (18) R-SO ₃ M (19) R-Ph-SO ₃ M (20) R-Np-SO ₃ M (21)

(In the formulas (18) to (21), R represents a hydrocarbon group having 6 to 30 carbon atoms which may contain an unsaturated bond;
M represents an alkali metal, Ph represents a phenylene group, and Np represents a naphthylene group. B) Nonionic surfactants include polyoxyethylene alkyl ethers, polyethylene glycol fatty acid esters, and polyoxyethylene fatty acid amides. C) Others, fluorosurfactants such as fluoroalkyl carboxylate, polyoxyethylene allyl glycidyl nonyl phenyl ether and its sulfate,
Reactive surfactants such as polyoxyethylene nonylpropenyl phenyl ether and its sulfates are also included. Of these, particularly preferred are those represented by the general formula (1)
8) Anionic surfactants represented by (21), which have lithium as M in the formula. These emulsifiers may be used in combination of two or more.

The solvent used in the emulsion polymerization is not particularly limited, but water is the most common, and if necessary, methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, isobutyl alcohol,
Alcohols such as tert-butyl alcohol, ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, butyl acetate, methyl formate and ethyl formate, diethyl ether, tetrahydrofuran (THF ), N, N-dimethylformamide (DMF),
Polar organic solvents such as amides such as N, N-dimethylacetamide and N-methylpyrrolidone, and sulfoxides such as dimethyl sulfoxide (DMSO) may be used, and aqueous solutions of these polar organic solvents may also be used. is there. Further, a plurality of these polar organic solvents may be used at the same time.

The radical initiator used in the emulsion polymerization includes lithium persulfate, sodium persulfate, potassium persulfate, rubidium persulfate, cesium persulfate, magnesium persulfate, calcium persulfate, strontium persulfate, persulfate, and the like. Peroxides such as persulfates such as barium, cumene hydroperoxide, tert-butyl hydroperoxide, dicumyl peroxide, di-tert-butyl hydroperoxide, hydrogen peroxide, benzoyl peroxide, lauroyl peroxide and the like, 2,2 ′ -Azobisisobutyronitrile, 1-[(1-cyano-1-methylethyl) azo]
Formamide, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (2-methylpropionamidine) dihydrochloride, 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 4,4′-azobis (4-cyanovaleric acid), 2,
2′-azobis (2,4-dimethylvaleronitrile),
Dimethyl 2,2'-azobis (2-methylpropionate), 2,2'-azobis [2- (2-imidazoline-
2-yl) propane] dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane],
2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2′-azobis {2-methyl-N-
[1,1-bis (hydroxymethyl) ethyl] propionamide}, 2,2′-azobis [2-methyl-N-
(2-hydroxyethyl) propionamide], 2,
2'-azobisisobutyramide dihydrate, 2,2'-
Azo compounds such as azobis [2- (hydroxymethyl) propionitrile] and 2,2′-azobis (2,4,4-trimethylpentane), hydrogen peroxide-ferrous salt, persulfate-sodium sulfite, Cumene hydroperoxide
Redox initiator systems such as ferrous salts and benzoyl peroxide-dimethylaniline. Among these, when water or an aqueous solution is used as a solvent, persulfates such as lithium persulfate, sodium persulfate, and potassium persulfate; 2,2′-azobis (2-methylpropionamidine) dihydrochloride; 4,4'-azobis (4-cyanovaleric acid), 2,2'-azobis [2- (2-imidazoline-
Water-soluble azo compounds such as [2-yl) propane] dihydrochloride are preferably used.

The micelle polymerization in the present invention is defined as a radical polymerizable surfactant, a polar solvent, and a radical initiator.
It is a polymerization form with one as an essential element, and it is possible to coexist with optional additives such as a copolymer monomer, a crosslinking agent, a plasticizer, a heat stabilizer, an antioxidant, an ultraviolet absorber, and an inorganic filler as necessary. I do not care. The micelle polymerization in the present invention is distinguished from the emulsion polymerization (mainly a radical polymerizable monomer) in that the main component of the product is a radical polymerizable surfactant.

Examples of the radical polymerizable surfactant used in the micelle polymerization include a lithium salt of ω-methacryloyloxyundecanesulfonic acid, which is a reactive anionic surfactant, a sodium salt, and ω-crotonoi. Lithium salt of roxyundecanesulfonic acid, also sodium salt, lithium salt of dodecylallylsulfosuccinic acid, sodium salt (e.g., Eleminol JS-2 supplied from Sanyo Chemical Co., Ltd., provided that Eleminol is a registered trademark), or the like, or Examples of the reactive nonionic surfactant include polyoxyethylene allyl glycidyl nonyl phenyl ether and its sulfate, and polyoxyethylene nonyl propenyl phenyl ether and its sulfate. These compounds are intended to fix the micellar structure by advancing radical polymerization inside micelles formed in a polar solvent.

The polar solvent used in the above-mentioned micelle polymerization is a solvent having an affinity for the hydrophilic structure of the above-mentioned radically polymerizable surfactant, and specific examples thereof include the solvents used in the above-mentioned emulsion polymerization. According to. Specific examples of the radical initiator used in the micelle polymerization are in accordance with the examples of the radical initiator used in the emulsion polymerization.

When the polymer fine particles obtained by the emulsion polymerization or micelle polymerization described above are used as a crosslinked polymer by coexisting a radical crosslinker in the polymerization system, a favorable effect can be obtained by improving heat resistance and mechanical strength. There is. The radical cross-linking agent referred to herein is a compound having two or more carbon-carbon unsaturated bonds in a molecule, for example, the above-mentioned α, ω-alkylene diol diacrylate derivative, polyalkylene glycol diacrylate derivative,
α, ω-polyesterdiol diacrylate derivative,
Polyfunctional acrylate derivatives, styrene derivatives such as divinylbenzene, vinyl esters such as vinyl 2-ethylhexanoate and divinyl adipate, and allyl esters such as triallyl trimellitate, diallyl chlorendate and diallyl hexahydrophthalate. Can be

(Reactive Surfactant) The polymer fine particles carrying the alkali metal salt of the present invention can be used in addition to the reactive surfactants exemplified above during the emulsion polymerization or micelle polymerization. It is more preferably produced by using a surfactant having an anionic group containing an element belonging to any of Group 15 or 16. That is, since the surfactant binds to an anionic group containing an element belonging to any one of Groups 13, 15, and 16 of the periodic table, the surfactant is used to perform the emulsion polymerization or the micelle polymerization. Thus, such an anionic group is introduced simultaneously with the formation of the polymer fine particles.

It is preferably used for the surfactant of the present invention.
Examples of the anionic group are described in the periodic table 13, 15 or 16 above.
As described for anionic groups containing elements belonging to any group
It is like. In the above surfactant, the anionic group has 3 carbon atoms.
It is necessary to bond to the above alkylene group.
However, the alkylene group has an alkyl as a substituent at its terminal.
Any one of a phenyl group, an acyl group, an alkoxy group, and an aromatic ring
To join. Here, the alkylene group having 3 or more carbon atoms means
At least three methylene groups (-CH_Two−) Chain required
Means an alkylene group having a structure, specifically, n-propyl
Ropylene group (-CH _Two−)_Three, N-butylene group (-CH
_Two−)_Four, N-hexylene group (-CH_Two−) ₆, N-o
Cutylene group (-CH_Two−)₈, N-dodecylene group (-C
H_Two−)₁₂, N-octadecylene group (-CH_Two−)₁₈etc
A linear alkylene group or a
Such as a structure in which any alkyl group such as
Can be exemplified.

The alkylene group having 3 or more carbon atoms has an alkyl group (for example, methyl group, isopropyl group, t
ert-butyl group, etc.), acyl group (for example, acetyl group,
Acryloyl group, methacryloyl group, crotonoyl group,
Examples thereof include those having a carbon-carbon double bond structure such as a fumaroyl group and a maleinoyl group, those having a carbon-carbon double bond structure of an ethynylcarbonyl group, and such acyl groups are ester bonds or nitrogen atoms via an oxygen atom. And an alkoxy group (for example, a methoxy group, an ethoxy group, a methoxyethoxy group, an ethoxyethoxy group, a benzyloxy group, a vinyloxy group, an allyloxy group, etc.). Or an aromatic ring (such as a phenyl group, a methylphenyl group (toluyl group), a vinylphenyl group, or a naphthyl group). Such an aromatic ring may be bonded to the terminal of the alkylene group via an ether bond via an oxygen atom. Not). Of these terminal structures, preferred are carbon-carbon multiple bond structures having radical polymerizability, specifically, acryloyl groups, methacryloyl groups, or acyl groups such as crotonoyl groups, vinyloxy groups and allyloxy groups. Aromatic rings such as an alkoxy group and a vinylphenyl group are exemplified. Among them, a preferable structure is an acryloyl group or a methacryloyl group having an ester bond or an amide bond, or a vinylphenyl group. Therefore, various structures of the following formula (22) can be exemplified as preferred specific structures of the surfactant of the present invention.

[0043]

Embedded image

(Means for Introducing Anionic Groups to the Surface of Fine Particles)
The means for introducing the anionic group exemplified above into the surface of the polymer fine particles is not limited, but a preferable method is to use an anion containing an element belonging to any one of groups 13, 15, or 16 of the periodic table as described above. The first example is the emulsion polymerization or micelle polymerization described above using a surfactant having a group.

As a preferred method for introducing the above-mentioned anionic group into the surface of the polymer fine particles, the conversion of the branched terminal group of the dendrimer into the anionic group is mentioned as a second example. The branched terminal groups of dendrimers are described, for example, in Leon, J .;
W. , Et al. J .; Am. Chem. Soc. ,
It is known that it can undergo a quantitative chemical reaction as reported in Vol. 118, p. 8847 (1996).
As an application example of such a method, for a dendrimer having an amino group as a molecular surface terminal (for example, one having the above-mentioned polypropyleneimine structure or polyamidoamine structure), a preferable sulfonic anhydride (RSO ₂ ) O or sulfonic acid halide RSO is used. ₂ X (where X is a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, and R is a fluorinated alkyl group having 5 or less carbon atoms, such as a trifluoromethyl group, a pentafluoroethyl group, A perfluoroalkyl group such as a fluoropropyl group and a nonafluorobutyl group, respectively) to give a sulfonamide, and then a caustic alkali such as lithium hydroxide, sodium hydroxide or potassium hydroxide, or the metal Of the amide by treatment with an aqueous solution of By substituting an alkali metal ion, it is converted into an alkali metal salt of the corresponding said sulfonic acid amide reaction may be exemplified. The amidation reaction is carried out using a suitable base (for example, a caustic alkali such as lithium hydroxide, sodium hydroxide, or potassium hydroxide, an alkali metal carbonate such as lithium carbonate, sodium carbonate, or potassium carbonate, triethylamine, diisopropylethylamine). In the presence of tertiary amines such as pyridine or the like, or water, alcohols such as methanol or ethanol, or polar solvents such as N, N-dimethylformamide (or a mixed solvent thereof). Can be. Of these bases, the use of caustic alkalis is particularly preferred because it can be converted to the desired alkali metal salt of sulfonic acid amide in one step.

(Alkali Metal Species) As the alkali metal used for the polymer fine particles carrying the alkali metal salt of the present invention, the smaller the atomic weight is, the more preferable it is from the viewpoint of energy density assuming the use for a secondary battery. Thus, preferably lithium, sodium or potassium is used, more preferably lithium or sodium, most preferably lithium.

(Polymer composition) When the polymer fine particles carrying the alkali metal salt of the present invention are used as a molded article having good mechanical properties, a polymer composition dispersed in an appropriate polymer matrix Sometimes it is good to do. The polymer used for such a matrix is not particularly limited, but when used as a solid electrolyte, electrochemical stability, heat resistance, and the like are often required. However, unlike a polymer used in a conventional solid electrolyte, coordination ability for a metal cation is not necessarily required. This is because the polymer fine particles of the present invention exhibit high ionic conductivity.

As a matrix usable when a solid electrolyte is assumed, polyethylene oxide (PEO),
Polyalkylene oxides such as polypropylene oxide, ethylene oxide-propylene oxide copolymer, acrylic resins such as polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polybutyl acrylate, polystyrene, styrene-butadiene block copolymer, styrene- Styrene resins such as ethylene-butadiene block copolymer and styrene-ethylene-propylene block copolymer, polyacrylonitrile (PAN), styrene-acrylonitrile copolymer (S
AN), polymers having acrylonitrile as a monomer such as acrylonitrile-butadiene-styrene copolymer (ABS), polyethylene, polypropylene, ethylene-propylene copolymer, butadiene rubber (NBR), polyolefins such as amorphous polyolefin, Aromatic polycarbonate resin (PC) such as bisphenol A polycarbonate, polyarylate resin (PAR), polyimide resin (PI), polyetherimide resin (PEI), polyphenylene ether resin (PPE), polyether sulfone resin (PES), etc. Examples include amorphous engineering plastics, phenolic resins, epoxy resins, and crosslinked resins such as crosslinked acrylic resins.

The above-mentioned polymer composition of the present invention is indispensable.
If necessary, a known lithium salt such as LiOH, L
i_TwoCO_Three, LiCl, LiBr, LiCH_ThreeCOO,
LiBF_Four, LiPF₆, LiClO_Four, LiAs
F₆, LiSbF₆, LiAlF _Four, CF_ThreeSO_ThreeL
i, (CF_ThreeSO_Two)_TwoNLi, (C_TwoF_FiveSO_Two)_Two
NLi or the like may be added.

The polymer composition of the present invention contains glass fibers, glass flakes, glass beads, mica, talc, montmorillonite, smectite, synthetic mica, synthetic smectite, silica, silica gel, titania, as long as the effects are not significantly impaired. Inorganic fillers such as zirconia, resin beads, hollow beads, heat stabilizers, antioxidants, ultraviolet absorbers, flame retardants, plasticizers and lubricants such as low molecular weight polyethylene glycol, petrolatum, glycerin esters, metal powders, semiconductor powders, graphite Any additives such as resin powder, pigment, dye, fluorescent dye, and compatibilizer may be added. The method of mixing the polymer fine-particle polyalkali metal salt of the present invention with the matrix polymer is arbitrary. For example, known methods such as mixing with monomers before high molecular weight, solution mixing, and melt mixing can be used. .

(Sheet-shaped molded article) The polymer fine particles carrying the alkali metal salt of the present invention or the polymer composition described above can be formed into a sheet-shaped molded article by any known method. It is very useful as a solid electrolyte for a secondary battery. When the sheet-shaped molded article of the present invention is used as a solid electrolyte for a secondary battery, the thickness of the molded article is usually 0.1 mm.
The thickness is 1 to 500 μm, preferably 0.2 to 200 μm, and more preferably 0.5 to 100 μm. Examples of the forming method include a melting method such as T-die extrusion film formation and inflation film formation, and a solution cast method such as bar coater film formation and spin casting.

[0052]

EXAMPLES Specific embodiments of the present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples unless it exceeds the gist thereof.

[Measurement Method] <FT-IR> FT / IR-8000 manufactured by JASCO Corporation
Type FT-IR, cast film of sample solution was prepared on KBr crystal and measured. <NMR> JNM-EX270 type FT-N manufactured by JEOL Ltd.
^{MR (1 H: 270MHz, 13} C: 67.8MHz). <Particle size of emulsion polymerization fine particles> SALD-20 manufactured by Shimadzu Corporation
Use a 00J light scattering meter. <Measurement of Ionic Conductivity> A SUS dish with an inner diameter of about 1.5 cm (thickness known) was prepared by using aqueous solutions of various solid electrolytes of the following examples.
And a 1 cm-diameter circular copper foil (thickness known), dried with warm air, and allowed to stand horizontally in a nitrogen air oven at 190 ° C. for 30 minutes to make it completely dry. Under an atmosphere of dry nitrogen, these are stacked so that the applied electrolyte membranes are bonded together, and compressed again with a SUS disk having a diameter of 1 cm.
Crimping was performed in a nitrogen stream oven at 190 ° C. for 5 minutes. The obtained sample was transferred into a chamber filled with dry argon, and an AC voltage having a variable frequency was applied between the SUS plate and the SUS disk to perform impedance measurement. The thickness d (unit: cm) of the formed electrolyte membrane was measured, and the area A (unit: cm ² ) of the copper foil and 100
From the real part R (unit: Ω) of the impedance at kHz, the ion conductivity (unit: S / cm) is expressed as d / (A · R)
It was calculated by the following calculation.

Example 1 Synthesis of Surfactant 3,3 '
-Diaminodipropylamine (1.0 equivalent),
18% methanol aqueous solution of lithium monohydrate (4.1 equivalent)
Dissolve in the solution and stir at room temperature
Ruphonyl fluoride C_FourF₉SO_TwoF (Aldrich
(Equivalent to 2.0 equivalents)
The solution was added dropwise. At this time, to keep the temperature below room temperature,
It cooled using the ice bath suitably. Left at room temperature overnight
After concentration, the resulting residue was dissolved in a mixed solvent of THF / water.
And added lithium hydroxide monohydrate (1.25 equivalents).
Eh, while stirring, acryloyl chloride CH_TwoCHC
OCI (1.1 eq) was added dropwise at room temperature. Leave overnight and concentrate
The condensed residue is subjected to reverse phase chromatography (polystyrene resin
Fat HP20SS; Mitsubishi Chemical, water-based)
A compound b of the formula (22) (hereinafter abbreviated as LiAm)
I got The structure is represented by sulfonamide in FT-IR.
Absorption band attributed to C is 1160cm ^-1What appeared near
When,¹H-NMR (solvent: CD_ThreeOD) Low field shift
That the signal of methylene hydrogen was observed, and
¹³C-NMR (solvent: CD_ThreeNonafluorobu at OD)
A signal derived from the carbon atom of the chill group was observed
Confirmed from.

Example 2 Synthesis of Latex Fine Particles Supporting Sulfonamide Salt Water (523.5 g), LiAm synthesized in Example 1 (8.85 g; 0.0116 mol),
And ammonium persulfate (1.22 g; 0.00535)
Mol) was charged into a nitrogen flow glass container and mechanical stirring was started at 40 ° C. Here, styrene (156.85)
g; 1.51 mol), methacrylic acid (7.16 g;
0832 mol), and divinylbenzene (4.98 g;
First, 36 mL of a mixed liquid (0.0383 mol) (hereinafter referred to as a monomer liquid) was added dropwise over 5 minutes. Next, the temperature was raised to 70 ° C., and the mixture was stirred for 15 minutes. Then, the rest of the monomer liquid was added dropwise over 5.5 hours. Thereafter, the temperature was raised to 85 ° C., and stirring was further continued for 4 hours to obtain an emulsion (hereinafter referred to as an ester emulsion). ) Got. The number average median of the particle size of the emulsion fine particles was 0.5 μm. A semi-permeable membrane (UC36-3, manufactured by Sanko Junyaku Co., Ltd.) that fractionates this emulsion to a molecular weight of 12,000 to 14,000 or less.
2-100) (hereinafter referred to as LiAm emulsion). Lithium and fluorine were detected by elemental analysis of the concentrated solids of this LiAm emulsion. Further, di-hydrochloric acid was added to the Li emulsion to make the liquid acidic, and then elemental analysis of the concentrated solid obtained by the above-mentioned dialysis purification revealed that lithium was substantially not contained (that is, protons and protons were easily contained). (The presence of lithium cations to be ion-exchanged), it was concluded that a Li ⁺ salt of sulfonamide corresponding to the structure of LiAm was carried on the surface of the emulsion particles.

Example 3 Synthesis of Dendrimer Polylithium Salt Astramol-Am-64, a polypropyleneimine dendrimer commercially available from Aldrich
(Catalog name is DAB-Am-64, 5th generation, theoretical molecular weight 7168, radius of inertia in heavy water 1.39 nm, having 64 primary amino groups on the molecular surface), dried N, N
-The residue was dissolved in dimethylformamide (DMF), a small amount of dry toluene was added, and the toluene was distilled off to remove residual water and low boiling point solvents. Then, pulverized anhydrous potassium carbonate (1.2 equivalents based on the primary amino group) was added, and trifluoromethanesulfonic anhydride (1.1 equivalents based on the primary amino group) was added dropwise while stirring and cooling with ice. The surface terminal amino group of the dendrimer was converted to a trifluoromethanesulfonic acid amide group. The progress of the reaction was confirmed by the fact that an absorption band attributed to sulfonamide appeared at about 1160 cm ^-1 in FT-IR. This product was purified by silica gel column chromatography (acetone / methylene chloride system), and ¹ H-NMR
(Solvent: CDCl ₃ ) 3.17 ppm and 3.67 p
the two signals which downfield shifts were observed in pm, and ¹³ C-NMR (solvent: CDCl ₃₎ at 113
ppm, 118 ppm, 123 ppm, and 127 pp
Since a signal derived from a carbon atom of a trifluoromethyl group (split into quartets by three F atoms) was observed in m, the target structure in which 64 primary amino groups were converted to trifluorosulfonamide Generation was confirmed. Next, this was dissolved in methanol, and an excess of an aqueous solution of lithium hydroxide was allowed to act on the solution to convert the proton of the trifluoromethanesulfonic acid amide group into a lithium salt corresponding to a lithium cation. Semi-permeable membrane (Spec
trum Medical Industries, I
nc. Spectra / Por Membrane
MWCO: 3,500) to remove and purify and remove excess low molecular weight water-soluble components such as lithium hydroxide and the like, and concentrate the resulting dendrimer polylithium salt (hereinafter abbreviated as PLS-D). ) Got.

[Preparation of Sheet-shaped Molded Body and Measurement of Ionic Conductivity] The results of the ionic conductivity measurement are summarized in Table 1.

Example 4 A mixture of polyethylene oxide having an average molecular weight of 300,000 and a sulfonimide lithium salt (C ₂ F ₅ SO ₂ ) ₂ NLi (hereinafter abbreviated as BETI) in water at a weight ratio of 61:39 was used. The solution was mixed (hereinafter, this aqueous solution is referred to as “aqueous solution A”). Then, aqueous solution A
And the LiAm emulsion obtained in Example 2 were dissolved in the former and the latter, respectively, in a weight ratio of solids of 50: 5.
0 was mixed. The ionic conductivity was measured using this aqueous solution as a raw material.
cm measurements were obtained.

Example 5 The ionic conductivity measurement was performed using the aqueous solution of PLS-D obtained in Example 3 as a raw material, and a measured value of 0.041 mS / cm was obtained.

<Example 6> A solution of Roux.D in the DMF solution of PLS-D obtained in Example 3 was added. C. Et al. , Mac
romol. Symp. 114, 211-216 (1997), a polypropylene oxide having a weight average molecular weight of about 600,000 (hereinafter referred to as PP).
O). However, they were blended so that the weight ratio between PLS-D and PPO was 75:25. The solution thus obtained is rolled nickel foil (thickness: 50 μm, manufactured by Fukuda Metal Co., Ltd.)
It was applied on the upper surface and heated under a dry nitrogen atmosphere to form a film while removing DMF. The ion conductivity of the obtained sheet-like molded product having a thickness of about 300 µm was 0.032 mS / cm.

[Comparative Example] The ionic conductivity was measured using the aqueous solution A of Example 4 as a raw material.
A measurement of 010 mS / cm was obtained.

[0062]

[Table 1] Experiment number Solid electrolyte composition (wt / wt) Ion conductivity (mS / cm) matrix Polylithium salt Example 4 50 (PEO / BETI) 50 (LTX supported on C ₄ F ₉ SO ₂ NLi) 6.3 Example 5 0 100 (dendrimer supported on CF ₃ SO ₂ NLi) 0.041 Example 6 25 (PPO) 75 (CF ₃ SO ₂ NLi supported dendrimer) 0.032 Comparative example 100 (PEO / BETI) 0 0.010

(However, in Table 1, LTX is an abbreviation meaning emulsion polymerized fine particles.)

[0064]

The polymer fine particles carrying the alkali metal salt of the present invention become a solid electrolyte exhibiting ionic conductivity when formed into a sheet, for example. Very large.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing dendron generations and focal points.

Claims (14)

[Claims] The present invention relates to a high-pressure carrier having an anion group containing an element selected from the group consisting of Groups 13, 15, and 16 on the surface of fine particles and supporting an alkali metal salt having a fine particle diameter of 0.001 to 1 μm. Molecular fine particles. 2. The alkali metal according to claim 1, wherein the negative charge center element of the anionic group is selected from the group consisting of boron, nitrogen, aluminum, phosphorus, arsenic, and antimony atoms. Polymer fine particles supporting salt. 3. An anionic group represented by the following general formula (1):
The polymer fine particles carrying an alkali metal salt according to claim 1 or 2, which are selected from the group consisting of (4). Embedded image (Where M ¹ is a boron atom or an aluminum atom, M ² is a phosphorus atom, an arsenic atom, or an antimony atom, L is an alkylene group having a halogen atom,
ⁿ (n is a natural number of 5 or less) independently represents any one of a halogen atom, an alkoxy group, an alkyl group, and an aromatic group. ) 4. The polymer particles carrying an alkali metal salt according to claim 1, wherein the alkali metal is lithium. 5. The polymer fine particle carrying an alkali metal salt according to claim 1, wherein the polymer fine particle is a hyperbranched polymer. 6. The polymer fine particles carrying an alkali metal salt according to claim 5, wherein the hyperbranched polymer has a dendrimer structure. 7. The polymer fine particles supporting an alkali metal salt according to claim 6, wherein the dendrimer structure is a polypropylene imine dendrimer structure. 8. The method for producing polymer fine particles carrying an alkali metal salt according to claim 1, wherein the polymer fine particles are produced by emulsion polymerization or micelle polymerization. 9. Periodic Table 1 during emulsion polymerization or micelle polymerization.
The method for producing polymer fine particles supporting an alkali metal salt according to claim 8, wherein a surfactant having an anionic group containing an element selected from the group consisting of groups 3, 15, and 16 is used. 10. The method according to claim 1, wherein the anionic group is represented by the general formula (1):
The method for producing polymer fine particles supporting an alkali metal salt according to claim 9, which is selected from the group consisting of (4). 11. The alkali metal salt according to claim 6, wherein the branched terminal group of the dendrimer is converted into an anionic group selected from the group consisting of the general formulas (1) to (4). A method for producing supported polymer fine particles. 12. The method for producing polymer fine particles carrying an alkali metal salt according to claim 9, wherein the anionic group has a sulfonic acid amide bond. 13. A sheet-shaped molded article containing the polymer fine particles carrying the alkali metal salt according to claim 1. Description: 14. A lithium ion secondary battery using the polymer fine particles carrying the alkali metal salt according to claim 1.