HK1049675B - Polyether polymer compounds as well as ion conductible polymer conpositions and elecrochemical devices using the same - Google Patents

Description

Polyether polymer compound, ion-conductive polymer composition using same, and electrochemical device

The technical field to which the invention belongs

The present invention relates to a novel polyether polymer compound, an ion-conductive polymer composition using the same, and an electrochemical device.

Background

It is known that a linear polyether such as polyethylene oxide dissolves an electrolyte salt to exhibit ion conductivity, but the ion conductivity is low, and thus the performance requirements as a material for an ion-conductive polymer composition cannot be satisfied.

Therefore, for example, there has been an attempt to improve ion conductivity by synthesizing a monomer capable of forming a side chain during polymerization by another method, and copolymerizing the monomer to obtain a polymer having a side chain.

The polyether having a side chain as described above exhibits higher ionic conductivity than the linear polyether, but has low ionic conductivity at around room temperature, and therefore, it is a problem to improve the ionic conductivity at around room temperature.

The present invention has been made in view of the above circumstances, and provides a polyether polymer capable of improving the ionic conductivity at around room temperature, an ion-conductive polymer composition using the same, and an electrochemical device.

Disclosure of the invention

The polyether polymer compound of the present invention has a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2) and/or formula (3), and has a polymerizable functional group and/or a non-polymerizable functional group at each terminal of a molecular chain.

Formula (1)

-CH₂CH₂O-

As the polymerizable functional group, 1 or 2 or more functional groups selected from a (meth) acrylic acid residue, an allyl group, and a vinyl group can be used, and as the non-polymerizable functional group, 1 or 2 or more functional groups selected from an alkyl group having 1 to 6 carbon atoms and a functional group containing a boron atom can be used.

The ion conductive polymer composition of the present invention contains 1 or 2 or more of the above polyether polymer compounds. Alternatively, 1 or 2 or more of the above polyether polymer compounds and an electrolyte salt are contained. The ion conductive polymer composition may further contain a nonaqueous solvent.

The ion conductive polymer composition of the present invention contains a product obtained by crosslinking a polyether polymer compound.

The electrochemical device of the present invention is formed using any one of the above-described ion-conductive polymer compositions.

Best mode for carrying out the invention

1. Polyether polymer compound

The polyether polymer compound of the present invention is obtained by, for example, reacting a starting material with ethylene oxide and 2, 3-epoxy-1-propanol, or reacting a starting material with 2, 3-epoxy-1-propanol to obtain a polymer compound, and introducing a polymerizable functional group and/or a non-polymerizable functional group into each end of a main chain and a side chain of the obtained polymer compound.

As the starting material, a compound having 1 or more active hydrogen residues or an alkoxide may be used.

Examples of the active hydrogen residue of the compound having 1 or more active hydrogen residues include hydroxyl groups, and those having 1 to 5 active hydrogen residues are preferable. Specific examples of the compound having 1 or more active hydrogen residues include triethylene glycol monomethyl ether, ethylene glycol, glycerol, diglycerol, pentaerythritol, and derivatives thereof.

Specific examples of the alkoxide include CH₃ONa or t-BuOK, and derivatives thereof.

The polyether polymer compound of the present invention has a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2) and/or formula (3). In 1 molecule, the number of the structural units represented by the formula (1) is 1 to 22800, preferably 5 to 11400, and more preferably 10 to 5700. The number of structural units of the formula (2) or (3) (in the case of both, the total number) is 1 to 13600, preferably 5 to 6800, and more preferably 10 to 3400 units in the same molecule.

Formula (1)

-CH₂CH₂O-

Examples of the polymerizable functional group introduced into each molecular terminal include a (meth) acrylic acid residue, an allyl group, a vinyl group and the like, and examples of the non-polymerizable functional group include an alkyl group and a functional group containing a boron atom.

The alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and particularly preferably a methyl group.

Examples of the functional group containing a boron atom include groups represented by the following formula (4) or (5).

In the formula (4), R¹¹、R¹²And R in the formula (5)²¹、R²²、R²³Which may be the same or different, each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an alkenyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, a cyano group, a hydroxyl group, a formyl group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, a sulfonyloxy group, an amino group, an alkylamino group, an arylamino group, a carboxyamino group, an oxysulfonyl amino group, a sulfamoyl group, an oxycarbonylamino group, a ureido group, an acyl group, an oxycarbonyl group, a carbamoyl group, a sulfonyl group, a sulfinyl group, an oxysulfonyl group, a^a)(R^b)，-O B(R^a)(R^b) or-OSi (R)^a)(R^b)(R^c)。R^a、R^bAnd R^cEach represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an alkenyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, a cyano group, a hydroxyl group, a formyl group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, a sulfonyloxy group, an amino group, an alkylamino group, an arylamino group, a carboxyamino group, an oxysulfonylamino group, a sulfamoyl group, an oxycarbonylamino group, a ureido group, an acyl group, an oxycarbonyl group, a carbamoyl group, a sulfonyl group, a sulfinyl group, an oxysulfonyl group, a sulfamoyl group, a. In the formula (4), R¹¹、R¹²And R in the formula (5)²¹、R²²、R²³May be bonded to each other to form a ring, and the ring may have a substituent. In addition, each group may be substituted with a substitutable group. In the formula (5), X⁺Represents an alkali metal ion, preferably a lithium ion.

The terminal of the molecular chain in the polyether polymer may be a polymerizable functional group, a non-polymerizable functional group, or both.

The molecular weight (Mw) of the polyether polymer compound of the present invention is not particularly limited, but is usually about 500 to 200 ten thousand, preferably about 1000 to 150 ten thousand.

2. Ion conductive polymer composition

The ion conductive polymer composition of the present invention contains the polyether polymer compound and an electrolyte salt, and may further contain a nonaqueous solvent as needed.

The kind of the electrolyte salt is not particularly limited, and a lithium salt, an ammonium salt, (C) may be used₂H₅)₄PBF₄And salts of protonic acids such as sulfuric acid and perchloric acid, salts containing boron atoms, ionic liquids, and the like.

Specific examples of the lithium salt include LiPF₆、LiClO₄、LiAsF₆、LiCF₃SO₃、LiN(CF₃SO₂)₂、LiN(C₂F₅SO₂)₂、LiC(CF₃SO₂)₃LiCl, LiF, LiBr, LiI, and derivatives thereof.

Specific examples of the ammonium salt include (CH)₃)₄NBF₄、(CH₃)₄NBr、(CH₃)₄NI、(CH₃)₄NClO₄、(C₂H₅)₄NBF₄And the like.

Examples of the boron atom-containing salt include those represented by the following formula (6).

In the formula (6), R³¹、R³²、R³³、R³⁴May be the same or different and each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an alkenyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, a cyano group, a hydroxyl group, a formyl group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, a sulfonyloxy group, an amino group, an alkylamino groupAryl, arylamino, carboxyamino, oxysulfonylamino, sulfamoyl, oxycarbonylamino, ureido, acyl, oxycarbonyl, carbamoyl, sulfonyl, sulfinyl, oxysulfonyl, sulfamoyl, carboxylic acid, sulfonic acid, phosphonic acid, heterocyclic, -B (R)^a)(R^b)，-OB(R^a)(R^b) or-OSi (R)^a)(R^b)(R^c)。R^a、R^bAnd R^cEach represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an alkenyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, a cyano group, a hydroxyl group, a formyl group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, a sulfonyloxy group, an amino group, an alkylamino group, an arylamino group, a carboxyamino group, an oxysulfonylamino group, a sulfamoyl group, an oxycarbonylamino group, a ureido group, an acyl group, an oxycarbonyl group, a carbamoyl group, a sulfonyl group, a sulfinyl group, an oxysulfonyl group, a sulfamoyl group, a carboxylic. In the formula (6), R³¹、R³²、R³³、R³⁴May be bonded to each other to form a ring, and the ring may have a substituent. In addition, each group may be substituted with a substitutable group. X⁺Represents an alkali metal ion, preferably a lithium ion.

Specific examples of the ionic liquid include pyridine, pyrimidine, pyridazine, pyrazine, triazine, oxazole, thiazole, imidazole, pyrazole, isoxazole, thiadiazole, oxadiazole, and 4-stage salts of derivatives thereof substituted with a substitutable group.

The concentration of the electrolyte salt is usually in the range of 1 to 10000 parts by weight, preferably 2 to 5000 parts by weight, and more preferably 5 to 2000 parts by weight, based on 100 parts by weight of the polyether polymer compound.

As the nonaqueous solvent, 1 or 2 or more kinds of aprotic solvents selected from carbonates, lactones, ethers, sulfolanes and dioxolanes can be used.

The concentration of the electrolyte salt in the nonaqueous solution obtained by dissolving the electrolyte salt in the nonaqueous solvent is usually in the range of 0.01 to 10mol/kg, preferably 0.02 to 6.0 mol/kg.

The mixing ratio of the polyether polymer to the nonaqueous solution is usually 1/99 to 99/1 (the same weight ratio hereinafter), preferably 1/99 to 50/50, and more preferably 1/99 to 30/70.

3. Electrochemical device

The ion conductive polymer composition of the present invention can be applied to various electrochemical devices, and examples thereof include lithium batteries, dye-sensitized solar cells, fuel cells, capacitors, and the like.

4. Examples of the embodiments

The present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

(1) Synthesis example of polyether Polymer

Synthesis example 1 (Synthesis of Compound 1)

KOH 9g was added to 1mol of glycerin as a starting material, the mixture was put into a pressure-resistant vessel, heated to 100 ℃ and then reduced in pressure by a vacuum pump until the reduced pressure became 5mmHg or less, and then heated to 120 ℃. Adding 20mol of ethylene oxide and 20mol of 2, 3-epoxy-1-propanol into the mixture to form a monomer mixed solution, and reacting at the temperature of 120 +/-5 ℃.

After the reaction was completed, 23mol of t-BuOK was put into a pressure resistant vessel, heated to 120 ℃ and depressurized by a vacuum pump until the reduced pressure became less than 5mmHg, alcoholization (aldolate) was performed, and cooled to 80 ℃. 23mol of methyl chloride are added to react at 80 +/-5 ℃. After completion of the reaction, excess acid was removed by an adsorbent, and dehydration and filtration were carried out to obtain a polyether polymer compound having a modified terminal.

Synthesis example 2 (Synthesis of Compound 2)

KOH 9g was added to 1mol of triethylene glycol as a starting material, the mixture was put into a pressure resistant vessel, heated to 100 ℃ and then reduced in pressure by a vacuum pump until the reduced pressure became 5mmHg or less, and then heated to 120 ℃. Adding 10mol of ethylene oxide and 3mol of 2, 3-epoxy-1-propanol into the mixture to form a monomer mixed solution, and reacting at the temperature of 120 +/-5 ℃.

After the reaction is finished, 3mol of t-BuOK is put into a pressure-resistant container, the temperature is raised to 120 ℃, the pressure is reduced by a vacuum pump until the reduced pressure reaches below 5mmHg, alcoholization is carried out, and the temperature is cooled to room temperature. 3mol of acryloyl chloride was added thereto, and the reaction was carried out at room temperature.

Further, 2' -dihydroxybiphenyl and borane (borane) were reacted in a molar ratio of 1: 1 in methylene chloride while cooling with ice, and methylene chloride was removed under reduced pressure to synthesize a boron compound. 2mol of the boron compound was added to the above reaction system, and the reaction was carried out at room temperature. Excess acid was removed by an adsorbent, and dehydration and filtration were carried out to obtain a polyether polymer compound having a modified terminal.

Synthesis example 3 (Synthesis of Compound 3)

KOH 9g was added to 1mol of ethylene glycol as a starting material, the mixture was put into a pressure vessel, heated to 100 ℃ and then reduced in pressure by a vacuum pump until the reduced pressure became 5mmHg or less, and then heated to 120 ℃. Adding 10mol of 2, 3-epoxy-1-propanol, and reacting at the temperature of 120 +/-5 ℃.

After the reaction is complete, 12mol of CH are added₃Placing OLi into a pressure-resistant container, heating to 120 deg.C, vacuum-pumping until the reduced pressure is below 5mmHg, alcoholizing, and cooling to room temperature.

In addition, 1, 1, 1, 3, 3, 3-hexafluoro-2-propanol and borane were reacted in a molar ratio of 3: 1 in dichloromethane at room temperature. 6mol of the product was added to the reaction system, and 6mol of acryloyl chloride was added thereto to carry out a reaction at room temperature. Purifying with adsorbent, dehydrating, and filtering to obtain end-modified polyether polymer compound.

Synthesis example 4 (Synthesis of Compound 4)

Will be CH as a starting material₃Placing ONalmol and dehydrated toluene 500ml into a pressure-resistant container, heating to 100 deg.C, adding ethylene oxide 1mol and 2, 3-epoxy-1-propane0.6mol of alcohol is mixed to form a monomer mixed solution, and the monomer mixed solution is reacted at the temperature of 100 +/-5 ℃.

After the reaction is finished, 0.603mol of t-BuOK is dissolved in 10 times of t-BuOH, the solution is put into a pressure-resistant container for alcoholization, the temperature is raised to 60 ℃, 0.603mol of acryloyl chloride is added, and the reaction is carried out at room temperature. After the reaction is finished, purifying by using an adsorbent, and removing the solvent under reduced pressure to obtain the end-modified polyether high molecular compound.

Synthesis example 5 (Synthesis of Compound 5)

KOH 9g was added to 1mol of triethylene glycol monomethyl ether as a starting material, the mixture was put into a pressure resistant vessel, heated to 100 ℃ and then reduced in pressure by a vacuum pump until the reduced pressure became 5mmHg or less, and then heated to 120 ℃. Adding 30mol of ethylene oxide and 50mol of 2, 3-epoxy-1-propanol into the mixture to form a monomer mixed solution, and reacting at the temperature of 120 +/-5 ℃.

After the reaction is finished, 30mol of t-BuOK is put into a pressure-resistant container, the temperature is raised to 120 ℃, the pressure is reduced by a vacuum pump until the reduced pressure reaches below 5mmHg, alcoholization is carried out, and the temperature is cooled to 80 ℃. 20mol of butyl chloride was added thereto, reacted at 80. + -. 5 ℃ and cooled to room temperature.

In addition, catechol and borane were reacted in a molar ratio of 1: 1 in methylene chloride while cooling with ice, and methylene chloride was removed under reduced pressure to synthesize a boron compound. 21mol of the boron compound was added to the above reaction system, and the reaction was carried out at room temperature. Further, 10mol of allyl chloride was added thereto, and the reaction was carried out at room temperature for 2 hours. After completion of the reaction, excess acid was removed by an adsorbent, and dehydration and filtration were carried out to obtain a polyether polymer compound having a modified terminal.

Synthesis example 6 (Synthesis of Compound 6)

The end-modified polyether polymer was synthesized in the same manner as in compound 4, except that the compounds were used in the kinds and amounts shown in table 1.

Synthesis example 7 (Synthesis of Compound 7)

A terminal-modified polyether polymer was synthesized in the same manner as in compound 1, except that the compounds were used in the kinds and amounts shown in table 1.

Synthesis example 8 (Synthesis of Compound 8)

A terminal-modified polyether polymer was synthesized in the same manner as in compound 1, except that the compounds were used in the kinds and amounts shown in table 1.

Synthesis example 9 (Synthesis of Compound 9)

The end-modified polyether polymer was synthesized in the same manner as in compound 4, except that the compounds were used in the kinds and amounts shown in table 1.

Synthesis example 10 (Synthesis of Compound 10)

The end-modified polyether polymer was synthesized in the same manner as in compound 4, except that the compounds were used in the kinds and amounts shown in table 1.

TABLE 1

	Starting material	Ethylene oxide (mol)	2, 3-epoxy-1-propanol (mol)	Alcoholizing reagent species/mol	Terminal-modifying Compound type/mol
						Compound 1	Glycerol	20	20	t-BuOK/23	Methyl chloride/23
Compound 2	Triethylene glycol	10	3	t-BuOK/3	Acryloyl chloride/32, 2' -biphenol borane/2
						Compound 3	Ethylene glycol	0	10	CH3OLi/12	Tris (1, 1, 1, 3, 3, 3-hexafluoroisopropyl) borate/6 acryloyl chloride/6
Compound 4	CH3ONa	1	0.6	t-BuOK/0.603(t-BuOH solution)	Acryloyl chloride/0.603
						Compound 5	Triethylene glycol monomethyl ether	30	50	t-BuOK/30	Butyl chloride/20 allyl chloride/10 catechol borane/21
Compound 6	t-BuOK	22	6	t-BuOK/6.001(t-BuOH solution)	Propyl chloride/5 acryloyl chloride/1.001
						Compound 7	Diglycerol	50	30	t-BuOK/34	Hexyl bromide/32 vinyl chloride/2
Compound 8	Pentaerythritol	100	100	t-BuOK/105	Methyl chloride/75 allyl chloride/30
						Compound 9	CH3ONa	10	1	t-BuOK/1.001(t-BuOH solution)	Ethyl chloride/0.2 allyl chloride/0.801
Compound 10	t-BuOK	2	13	t-BuOK/13.001(t-BuOH solution)	Methyl chloride/12.001 vinyl chloride/1

(2) Preparation and evaluation of ion-conductive Polymer composition

The polyether polymer compound of the present invention can be used in electrochemical devices for various applications utilizing ion conductivity characteristics, and in the following examples and comparative examples, the ion conductivity of an ion-conductive polymer composition using the polyether polymer compound was evaluated, and a lithium salt was used as an electrolyte salt.

The ion conductivity of the ion conductive polymer composition was evaluated by the following method. Each of the ion conductive polymer compositions was made into a film with a thickness of 500 μm, punched into a 13 phi hole, and sandwiched by 2 pieces of 13 phi lithium metal, and the resistance value of the ion conductive polymer composition was measured at 20 ℃ by the complex impedance method, and the ion conductivity was determined from the resistance value.

[ example 1]

2g of Compound 1 and 8g of Compound 2, 2g of LiI, and 0.1g of AIBN were dissolved in 1g of acetonitrile at 40 ℃ and poured between glass plates, followed by vacuum drying at 80 ℃ for 24 hours to obtain an ion-conductive polymer composition having a thickness of 500. mu.m.

[ examples 2 to 4]

An ion conductive polymer composition was obtained in the same manner as in example 1, except that the kinds and amounts of the compounds and salts shown in table 2 were used.

[ example 5]

1g of Compound 4, 2.7g of Li [ (CF)₃SO₂)₂N]9g of gamma butyrolactone, 0.1g of AIBN were mixed and dissolved, and the mixture was poured between glass plates, and then left at 80 ℃ for 2 hours under an argon atmosphere to obtain an ion conductive polymer composition having a thickness of 500. mu.m.

[ examples 6 to 8]

An ion conductive polymer composition was obtained in the same manner as in example 5, except that the kinds and amounts of the compounds, salts, and nonaqueous solvents shown in table 2 were used.

Comparative example 1

An ion conductive polymer composition was obtained in the same manner as in example 1, except that the kinds and amounts of the compounds and salts shown in table 2 were used.

Comparative example 2

An ion conductive polymer composition was obtained in the same manner as in example 5, except that the kinds and amounts of the compounds, salts, and nonaqueous solvents shown in table 2 were used.

In the above examples and comparative examples, the kinds and amounts of the compounds, salts, and nonaqueous solvents, and the ionic conductivities are shown in table 2.

TABLE 2

	Kind/amount of Compound used	Kind/amount of electrolyte salt	Kind/amount of non-aqueous solvent	Ionic conductivity (S/cm)
					Example 1	Compound 1/2g + Compound 2/8g	LiI/2g	-	1×10-4
Example 2	Compound 3/5g + Compound 6/5g	LiBF4/0.5g	-	3×10-4
					Example 3	Compound 5/10g	LiPF4/3g	-	2×10-4
Example 4	Compound 8/10g	LiClO4/1g	-	1×10-4
					Example 5	Compound 4/1g	Li[(CF3SO2)2N]/2.7g	GBL/9g	3.0×10-3
Example 6	Compound 7/1g	LiBF4/0.5g	EC/2g+GBL/6g	1.7×10-3
					Example 7	Compound 9/1g	LiPF4/3g	EC/2g+GBL/5g+DEC/1g	2.5×10-3
Example 8	Compound 10/1g	LiClO4/1g	PC/3g+GBL/3g	2.0×10-3
					Comparative example 1	PEO/10g with a molecular weight of 15 ten thousand	Li[(CF3SO2)2N]/3g	-	9×10-7
Comparative example 2	PEO/1g with a molecular weight of 15 ten thousand	LiBF4/1g	GBL/9g	Is not measurable

In addition, the abbreviations of the nonaqueous solvents in table 2 represent the following:

GBL: γ -butyrolactone, EC: ethylene carbonate, DEC: diethyl carbonate, PC: propylene carbonate

Industrial applicability

The ion-conductive polymer composition using the polyether polymer of the present invention can exhibit high ion conductivity even at room temperature, and is suitable for various electrochemical devices using the ion-conductive polymer composition.

Claims (10)

1. The polyether polymer compound is characterized by having a structural unit represented by formula (1) and at least one of a structural unit represented by formula (2) and a structural unit represented by formula (3), wherein the structural units represented by formulae (1), (2) and (3) are represented by the following formula, the polyether polymer compound is prepared by reacting an initiator with at least 2, 3-epoxy-1-propanol, a polymerizable functional group is bonded to at least 1 end of a molecular chain, and a polymerizable functional group or a non-polymerizable functional group is bonded to each other end of the molecular chain.

2. A polyether polymer compound according to claim 1, wherein said polyether polymer compound is obtained by reacting a starting material with 2, 3-epoxy-1-propanol and ethylene oxide.

3. A polyether polymer compound according to claim 1 or 2, wherein the initiator is a compound or alkoxide having 1 or more active hydrogen residues.

4. The polyether polymer compound according to claim 1, wherein the polymerizable functional group is 1 or 2 or more species selected from the group consisting of a (meth) acrylic acid residue, an allyl group and a vinyl group, and the non-polymerizable functional group is 1 or 2 or more species selected from the group consisting of an alkyl group having 1 to 6 carbon atoms and a functional group containing a boron atom.

5. An ion-conductive polymer composition comprising 1 or 2 or more kinds of the polyether polymer compounds according to claim 1.

6. An ion-conductive polymer composition comprising 1 or 2 or more of the polyether polymer compounds according to claim 1 and an electrolyte salt.

7. The ion-conductive polymer composition according to claim 6, further comprising a nonaqueous solvent.

8. The ion-conductive polymer composition according to any one of claims 5 to 7, wherein the polyether polymer compound is crosslinked.

9. An electrochemical device using the ion-conductive polymer composition according to any one of claims 5 to 7.

10. An electrochemical device using the ion-conductive polymer composition according to claim 8.