KR101700116B1 - Gel polymer electrolyte composition and electrochromic device using the same - Google Patents

Abstract

The present invention relates to a gel polymer electrolyte composition and an electrochromic device using the gel polymer electrolyte composition. More particularly, the present invention relates to an electrochromic device comprising a 4- to 6-functional acrylic compound, an ionic liquid, a polymerization initiator and a metal salt. A gel polymer electrolyte composition which is easy to maintain the stability of the manufacturing process and product by suppressing the volume change and has an excellent response speed due to an improved ionic conductivity and is easy to deform the device such as thin film and film form, And a color changing element.

Description

TECHNICAL FIELD [0001] The present invention relates to a gel polymer electrolyte composition and an electrochromic device using the gel polymer electrolyte composition.

The present invention relates to a gel polymer electrolyte composition which is capable of controlling the reaction rate and curing degree during polymerization and maintaining the stability of the production process and the product as well as being capable of thinning and processing in the form of film, without the problem of electrolyte depletion and leakage, And an electrochromic device using the same.

Elctrochromic devices are devices that change the light transmission characteristics by using the principle that the electric oxidation-reduction reaction proceeds according to the application of the electric field to change the color of the electrochromic material. This is widely used not only for display devices such as mobile phones, camcorders, notebooks, but also for automobile room mirrors and window smart windows.

1, the electrochromic device generally includes first and second electrodes 10 and 20 formed with transparent electroconductive layers 12 and 22 on a substrate 11 and 21 to which an electric field is applied, The electrochromic material layer 31, 32, which is laminated on the conductive layers 12, 22 and changed in color by the applied electric current, includes an electrolyte 50 for ion conduction and a sealing material 40 for sealing the same. .

The electrolyte 50 may be a solid electrolyte deposited on the electrochromic material layers 31 and 32 or a liquid electrolyte dispersed therein.

The solid electrolyte is excellent in terms of stability of the electrochromic device, but has a disadvantage in that it is difficult to commercialize the electrochromic device due to its low performance. The liquid electrolyte has a disadvantage in that the organic solvent is volatilized and depleted, there is a liquid leakage problem in manufacturing the device, the decoloration rate is slow, and the organic material is easily decomposed when the coloring-decoloring is repeated. Further, it is difficult to maintain the stability of the product due to side reaction with the element constituting material or volume change due to polymerization, and it is disadvantageous in that it can not be made thin and can not be processed in a film form.

In order to solve this problem, U.S. Patent No. 6,667,825 discloses a liquid electrolyte including an ionic liquid and improved stability and lifetime. However, since an ionic liquid is used as a liquid electrolyte, electrolyte leakage, It is still difficult to apply to film-type processing.

In addition, U.S. Patent No. 5,872,602 discloses a _{AlCl 3 -EMICI (aluminum chloride-1} -ethyl-3-methylimidazolium chloride) ionic liquid, including but the electrolyte address the depletion, a problem of electrolyte degradation is disclosed, the ionic liquid Has a disadvantage in that it reacts with a small amount of organic-inorganic compound which releases a toxic gas when exposed to a small amount of water or oxygen and is added in a small amount in the electrolyte, and is easily decomposed particularly at 150 ° C or higher.

Korean Patent No. 0729500 discloses a gel polymer electrolyte impregnated with an ionic liquid without an organic solvent. However, since the vinyl compound used as a monomer capable of forming a gel polymer is highly reactive, the storage stability of the electrolyte is low and polymerization There is a problem of a yellowing phenomenon caused by the initiator and a decrease in the transmittance.

An object of the present invention is to provide a gel polymer electrolyte composition which has high ionic conductivity, does not contain an organic solvent, has no problem of electrolyte depletion and leakage, and has no side reaction with a constituent material.

Another object of the present invention is to provide a gel polymer electrolyte composition capable of controlling the reaction rate and degree of curing at the time of polymerization and having a small volume change to maintain the stability of the production process and the product, do.

It is another object of the present invention to provide an electrochromic device including the gel polymer electrolyte composition and having improved performance.

1. A gel polymer electrolyte composition comprising a 4- to 6-functional acrylic compound, an ionic liquid, a polymerization initiator, and a metal salt.

2. The gel polymer electrolyte composition according to 1 above, wherein the 4- or 6-functional acrylic compound is at least one selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (2)

또는

이고, R₁ 내지 R₆ 중 4개 이상이

이며; R₇ 내지 R₁₀은

이고; R₁₁은 수소 원자 또는 탄소수 1-6의 알킬기임).(Wherein R ₁ to R ₆ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,

or

, And four or more of R &_lt; ₁ > to R &_lt; _{6 &}

; R ₇ to R ₁₀ are

ego; And R < ₁₁ > is a hydrogen atom or an alkyl group having 1-6 carbon atoms.

3. The composition of claim 2, wherein the 4- to 6-functional acrylic compound is selected from the group consisting of ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate At least one gel polymer electrolyte composition.

4. The gel polymer electrolyte composition according to 3 above, wherein the 4- to 6-functional acrylic compound is dipentaerythritol hexaacrylate.

5. The gel polymer electrolyte composition according to item 1, wherein the weight ratio (based on solid content) of the 4- to 6-functional acrylic compound, the ionic liquid and the polymerization initiator is 1.5-7: 2.5-8.5: 0.03-1.

6. The gel polymer electrolyte composition according to 5 above, wherein the weight ratio (based on solid content) of the 4- to 6-functional acrylic compound, the ionic liquid and the polymerization initiator is 4.5-5.2: 4.7-5.4: 0.03-0.3.

7. The gel polymer electrolyte composition of 1 above, wherein the ionic liquid is a compound in which an ion is combined with an ion having a cation containing at least one nitrogen atom.

8. The composition of claim 7 wherein the ionic liquid is selected from the group consisting of ammonium, imidazolium, oxazolium, piperidinium, pyrazinium, pyrazolium, pyridazinium, pyridinium, pyrimidinium, pyrrolidinium, pyrrolinium, with a selected cation from the group consisting of blood rolryum, thiazolium and ^{triazolium, F -, Cl -, Br} -, I -, NO 3 -, (CN) 2 N -, BF 4 -, ClO 4 -, RSO 3 - , RCOO ^-, PF ₆ (wherein, R is an alkyl group or a phenyl group having a carbon number of _{^{1-9) -, (CF 3)}} 2 PF 4 -, (CF 3) 3 PF 3 -, (CF 3) 4 PF 2 -, ( ^{_{CF 3) 5 PF -, (}} CF 3) 6 P -, (CF 3 SO 3 -) 2, (CF 2 CF 2 SO 3 -) 2, (C 2 F 5 SO 2) 2 N -, (CF 3 ^{_{SO 3) 2 N -, (}} CF 3 SO 2) (CF 3 CO) N -, CF 3 CF 2 (CF 3) 2 CO -, (CF 3 SO 2) 2 CH -, (SF 5) 3 C - _{, (CF 3 SO 2) 3} C -, CF 3 (CF 2) 7 SO 3 -, CF 3 COO -, C 3 F 7 COO -, CF 3 SO 3 - and C ₄ F ₉ SO ₃ ^- group consisting of ≪ / RTI > wherein the anion is selected from the group consisting of anions.

9. The gel polymer electrolyte composition according to 1 above, wherein the metal salt is an alkali metal salt.

10. The gel polymer electrolyte composition according to 1 above, wherein the metal salt is contained so that the concentration of the cation of the metal salt is 0.5 to 1.5 mol / L.

11. An electrochromic device comprising a first electrode, a second electrode, an electrochromic material, and an electrolyte formed by photo-curing of the gel polymer electrolyte composition of any one of items 1 to 10 above.

12. The electrochromic device of claim 11, wherein the electrolyte is in-situ polymerized between the first and second electrodes.

The gel polymer electrolyte composition of the present invention has improved ionic conductivity at a level higher than that of a liquid electrolyte, so that when applied to an electrochromic device, the electrochromic device exhibits a good response rate and secures excellent electrochromic properties.

In addition, the composition of the present invention does not contain an organic solvent and thus has no problem of electrolyte depletion and leakage, has no side reaction with the constituent materials of the device, easily controls the reaction rate and curing degree upon polymerization, And the stability of the product can be maintained.

In addition, since the composition of the present invention can be manufactured on various substrates such as plastic as well as glass, it is possible to easily deform the structure of the device by a thin film and a film form, and to simplify the process.

1 is a cross-sectional view of a general electrochromic device,
2 is a graph showing the degree of polymerization of the gel polymer electrolyte composition according to Example 6 of the present invention measured by the photopolymerization time and measuring the transmittance (T) using FT-IR.

The present invention relates to a gel polymer electrolyte composition and an electrochromic device using the gel polymer electrolyte composition.

Hereinafter, the present invention will be described in detail.

The gel polymer electrolyte composition of the present invention comprises a 4 to 6 functional acrylic compound, An ionic liquid, a polymerization initiator, and a metal salt.

The 4- to 6-functional acrylic compound is a compound capable of forming a gel polymer electrolyte by polymerization by photocuring with an ionic liquid or an ionic liquid and a polymerization initiator. This compound can further improve the ionic conductivity, It is possible to form a gel polymer electrolyte having a high reaction speed, easy control of the degree of curing, a low volume shrinkage and expansion, and an appropriate mechanical strength.

As the 4- to 6-functional acrylic compounds, Include compounds represented by the following general formula (1) or (2), which may be used alone or in combination of two or more:

[Chemical Formula 1]

(2)

또는

이고, R₁ 내지 R₆ 중 4개 이상이

이며; R₇ 내지 R₁₀은

이고; R₁₁은 수소 원자 또는 탄소수 1-6의 알킬기임).(Wherein R ₁ to R ₆ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,

or

, And four or more of R &_lt; ₁ > to R &_lt; _{6 &}

; R ₇ to R ₁₀ are

ego; And R < ₁₁ > is a hydrogen atom or an alkyl group having 1-6 carbon atoms.

As the 4- to 6-functional acrylic compounds, Ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate and the like are more preferable, and the 5 or 6-functional acrylic-based Compounds such as dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate, and most preferably dipentaerythritol hexaacrylate. The 5 or 6 functional acrylic compound represented by the formula (1) has an oxyalkylene group having a polarity at the center and contains at least five functional acrylic groups at the terminals, thereby improving the ionic conductivity and controlling the degree of curing It is easier.

A small amount of a vinyl compound can be mixed and used as a compound capable of forming a gel polymer electrolyte by photo-curing together with a 4- to 6-functional acrylic compound.

The kind of the vinyl compound is not particularly limited and includes, for example, acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, methyl styrene, vinyl ester compounds, vinyl chloride, vinylidene chloride, acrylamide, tetrafluoro Ethylene, vinyl acetate, methyl vinyl ketone, ethylene, styrene, paramethoxystyrene, p-cyanostyrene, polyethylene glycol acrylate, etc. These may be used alone or in combination of two or more. The vinyl compound can be used in a small amount insofar as the yellowing by the polymerization initiator does not occur.

An ionic liquid is an ionic compound made by combining ions of a cation and an anion and is an ionic salt having a property of being present as a liquid at a temperature of 100 ° C or lower. In particular, in the present invention, the ionic liquid preferably contains at least one nitrogen atom. The free radicals generated by the nitrogen atom promote the rate of polymerization reaction for gel polymer electrolyte formation to suppress shrinkage and expansion and impart appropriate mechanical strength.

Ionic liquids are non-volatile, non-flammable, have high thermal stability and ionic conductivity, have a high polarity, and have unique characteristics of dissolving inorganic and organic metals and maintaining liquid state at a wide range of temperatures. It is a substance that is being studied as a next generation environmentally friendly solvent.

Examples of the cation constituting the ionic liquid include ammonium, imidazolium, oxazolium, piperidinium, pyrazinium, pyrazine, But are not limited to, pyrazolium, pyridazinium, pyridinium, pyrimidinium, pyrrolidinium, pyrrolinium, pyrrolium, thiazolium, , Triazolium, and the like.

(3)

(Wherein R ₁₂ to R ₁₇ are each independently an alkyl group having 1 to 9 carbon atoms or a phenyl group).

The anion constituting the ionic liquid includes F ^- , Cl ^- , Br ^- , I ^- , NO ₃ ^- , (CN) ₂ N ^- , BF ₄ ^- , ClO ₄ ^- , RSO ₃ ^- -9 alkyl or phenyl), RCOO ^- (wherein, R is an alkyl group or a phenyl group having a carbon number of ^{_{1-9), PF 6 -, (}} CF 3) 2 PF 4 -, (CF 3) 3 PF 3 -, (CF 3 ) ₄ PF ₂ ^- , (CF ₃ ) ₅ PF ^- , (CF ₃ ) ₆ P ^- , (CF ₃ SO ₃ ^- ) ₂ , (CF ₂ CF ₂ SO ₃ ^- ) ₂ , (C ₂ F ₅ SO ₂ ) _{^{2 N -, (CF 3 SO}} 3) 2 N -, (CF 3 SO 2) (CF 3 CO) N -, CF 3 CF 2 (CF 3) 2 CO -, (CF 3 SO 2) 2 CH -, ^{_{(SF 5) 3 C -,}} (CF 3 SO 2) 3 C -, CF 3 (CF 2) 7 SO 3 -, CF 3 COO -, C 3 F 7 COO -, CF 3 SO 3 -, C 4 F ₉ SO ₃ ^- , and the like.

The polymerization initiator is for improving the curing reaction efficiency of the gel polymer electrolyte composition, and includes a photo-radical generator which generates an active radical by light irradiation and an acid generator which generates an acid, At the same time. These may be used alone or in combination of two or more.

Examples of the photo radical generator include acetophenone, benzoin, benzophenone, thioxanthone and triazine compounds.

Examples of the acetophenone-based compound include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 2- 1-one, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan- 2-methyl-1- [4- (1-methylvinyl) phenyl] propan-1-one Oligomers and the like.

Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

Examples of the benzophenone compound include benzophenone, methyl o-benzoyl benzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3 ', 4,4'- Oxycarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, and the like.

Examples of the thioxanthone compound include 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1- City Oak Mountain, and the like.

Examples of the triazine compound include 2,4-bis (trichloromethyl) -6- (4-methoxyphenyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (Methoxynaphthyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6-piperonyl-1,3,5-triazine, 2,4- Methyl) -6- (4-methoxystyryl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- 2- (furan-2-yl) ethenyl] -1,3,5-triazine, 2,4,6-trichloromethyl- Bis (trichloromethyl) -6- [2- (4-diethylamino-2-methylphenyl) ethenyl] -1,3,5-triazine, 2,4- - [2- (3,4-dimethoxyphenyl) ethenyl] -1,3,5-triazine.

Examples of the photo radical generator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenyl- '-Bimidazole, 10-butyl-2-chloroacridone, 2-ethyl anthraquinone, 9,10-phenanthrenequinone, camphorquinone, methylphenylglyoxylate and titanocene compounds.

Examples of the photopolymerization initiator include commercially available products such as Opethoma (Asahi Kogyo Co.), IGACURE (Ciba), Seid SI-60L, UVI-6990 (Union Carbide), BBI-1C3, MPI- -103, DTS-103, NAT-103, NDS-103 (Midori Chemical Industries, Ltd.).

Examples of the acid generator include 4-hydroxyphenyldimethylsulfonium p-toluenesulfonate, 4-hydroxyphenyldimethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium p-toluenesulfonate, 4-acetic acid Triphenylsulfonium hexafluoroantimonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium hexafluoroantimonate, diphenyliodonium p-toluenesulfonate, diphenyliodonium Onium salts such as hexafluoroantimonate; Nitrobenzyl tosylate, benzoin tosylate, and the like.

It is preferable that the 4- to 6-functional acrylic compound, the ionic liquid and the polymerization initiator are contained in the gel polymer electrolyte composition in a weight ratio (based on solids) of 1.5-7: 2.5-8.5: 0.03-1, more preferably 1.7- 7: 2.9-5.5: 0.03-0.7, most preferably 4.5-5.2: 4.7-5.4: 0.03-0.3. At this time, the total weight ratio of the 4 to 6 functional acrylic compounds, the ionic liquid and the polymerization initiator is based on 10. When the weight ratio is not within the above range, for example, when the weight ratio of the 4- to 6-functional acrylic compound is less than 1.5 or the weight ratio of the ionic liquid is more than 8.5, gel polymer electrolyte formation is weak and it is difficult to impart appropriate mechanical strength, If the weight ratio of the hexafunctional acrylic compound is more than 7 or the weight ratio of the ionic liquid is less than 2.5, the effect of improving the ionic conductivity is insignificant and the electrochromic rate may be lowered. Further, in these ranges, it is difficult to give a synergistic effect of ionic conductivity and an appropriate mechanical strength to the gel polymer electrolyte due to the combined use of the 4- to 6-functional acrylic compound and the ionic liquid.

The metal salt is used to provide metal ions to the gel polymer electrolyte composition. The metal salt is inserted or removed in the electrochromic material to change the oxidation number of the transition metal contained in the electrochromic material, thereby changing the optical property of the electrochromic material itself .

The metal salt is preferably an alkali metal salt comprising a combination of a cation selected from the group consisting of Li ⁺ , Na ⁺ , K ^+, and Cs ⁺ and anion constituting an ionic liquid. When the anion constituting the metal salt is different from the anion constituting the ionic liquid, the solubility of the metal salt in the gel polymer electrolyte may be lowered.

In particular, when an inorganic metal such as WO ₃ or NiO is used as an electrochromic material of an electrochromic device, it is preferable to use an alkali metal salt containing a lithium cation such as LiClO ₄ , LiAsF ₆ , LiSbF ₆ , LiPF ₆ or LiBF ₄ And more preferably LiPF ₆ or LiBF ₄ .

The metal salt may be used by appropriately adjusting the content depending on the type of the ionic liquid, the composition of the electrolyte composition, and the kind of the electrochromic material, without affecting other components of the gel polymer electrolyte composition. The metal salt is preferably contained so that the concentration of the cation of the metal salt is 0.5 to 1.5 mol / L based on the gel polymer electrolyte composition. When the concentration of the cation of the metal salt is less than 0.5 mol / L, the solubility in the gel polymer electrolyte composition is good, but the number of free ions that can be conducted is small and it is difficult to exhibit sufficient performance as an electrolyte of the electrochromic device. If the concentration is more than 1.5 mol / L, dissolution of the gel polymer electrolyte composition is not performed well and ion-paring is formed. That is, after the ion is dissolved, In the case of ion pair or ion aggregation, migration is impossible and consequently the number of free ions is reduced and the conductivity is also lowered.

The method for producing the gel polymer electrolyte using the gel polymer electrolyte composition of the present invention is not particularly limited. For example, it can be produced by an in-situ polymerization reaction by photocuring in an electrode. In this case, the in-situ polymerization is a method in which the gel polymer electrolyte composition is injected between the two electrodes and then polymerized, which is easier to handle than controlling the polymerized electrolyte, which is useful in the production of an electrochromic device. In addition, there is a good advantage of wetting and contact between the gel polymer electrolyte and the electrode.

Polymerization conditions of the gel polymer electrolyte by photo-curing are not particularly limited, and can be carried out at a polymerization time of 10 minutes or less, for example, at a normal light irradiation dose.

The electrochromic device of the present invention is characterized by comprising a first electrode, a second electrode, an electrochromic material and an electrolyte formed by photocuring of the gel polymer electrolyte composition.

The first electrode and the second electrode may have a structure in which a transparent conductive layer is formed on a substrate.

The substrate and the transparent conductive layer are not particularly limited as long as they are well known in the art. Examples of the conductive material for forming the transparent conductive layer include ITO (indium doped tin oxide), ATO (antimony doped tin oxide), FTO (fluorine doped tin oxide ), Indium doped zinc oxide (IZO), and ZnO. A transparent conductive layer can be formed on the substrate by depositing a conductive material by a known method such as sputtering, electron beam evaporation, chemical vapor deposition, or sol-gel coating.

Examples of the electrochromic material include, but are not limited to, inorganic oxides such as WO ₃ , Ir (OH) x, MoO ₃ , V ₂ O ₅ , TiO ₂ and NiO; Conductive polymers such as polypyrrole, polyaniline, polyazulene, polypyridine, polyindole, polycarbazole, polyazine, and polythiophene; Organic coloring materials such as violon, anthraquinone, phenothiazine, and the like.

The method of laminating the electrochromic material on the electrode is not particularly limited as long as the thin film can be formed at a constant height from the basal plane along the surface profile. For example, a vacuum deposition method such as sputtering can be mentioned.

Of the electrochromic materials, for example, WO ₃ is a substance that is colored by a reduction reaction, and NiO is a substance that is colored by an oxidation reaction. The electrochemical mechanism in which electrochromism occurs in an electrochromic device containing such an inorganic metal oxide is explained as shown in Scheme 1. Specifically, when a voltage is applied to the electrochromic device, the proton (H ⁺ ) or lithium ion (Li ⁺ ) contained in the electrolyte is inserted or eliminated as an electrochromic material depending on the polarity of the electric current. The change in the oxidation number of the transition metal contained in the electrochromic material changes the optical characteristic of the electrochromic material itself, for example, the transmittance (color).

[Reaction Scheme 1]

WO ₃ (transparent) + xe + xM ↔ MxWO ₃ (dark blue)

(Wherein M is a proton or an alkali metal cation such as Li ⁺ ).

The electrochromic device thus constructed may be manufactured according to a conventional method known in the art, for example, (a) preparing a first electrode and a second electrode; (b) injecting the gel polymer electrolyte composition according to the present invention between the prepared first electrode and the second electrode, and then sealing the gel polymer electrolyte composition; And (c) polymerizing the injected electrolyte composition to form a gel polymer electrolyte.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to be illustrative of the invention and are not intended to limit the scope of the claims. It will be apparent to those skilled in the art that such variations and modifications are within the scope of the appended claims.

Example

Example 1

(1) Gel polymer electrolyte composition

Dipentaerythritol hexaacrylate (DPHA), ionic liquid 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide [BMI-TFSI], diethoxyacetophenone (DEAP) : 8: 0.05 (based on solid content), and LiBF ₄ (Li ⁺ concentration: 1 mol / L) was added to prepare a gel polymer electrolyte composition.

(2) The electrochromic device

An ITO transparent conductive layer was deposited on the glass substrate to a thickness of 150 nm, and a 200 nm thick WO ₃ electrochromic material thin film was formed thereon by a sputtering method to prepare a working electrode. Further, a counter electrode having a NiO thin film with a thickness of 300 nm was manufactured in the same manner as the working electrode. Except for a part of the rim of the working electrode and the counter electrode (electrolyte injection hole), to form an electrochromic device intermediate without electrolyte. The gel polymer electrolyte composition prepared in (1) was injected into the prepared intermediate, the injection port was sealed with a sealing material, and then irradiated with light for 1 minute in an ultraviolet (UV) exposure apparatus to prepare an electrochromic device by in-situ polymerization.

Example 2

(DPHA), 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide [1-butyl-3-methylimidazolium iodide] was used in the same manner as in Example 1, except that dipentaerythritol hexaacrylate BMI-TFSI], and diethoxyacetophenone (DEAP) at a weight ratio of 4.9: 5: 0.1.

Example 3

(DPHA), 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide [1-butyl-3-methylimidazolium iodide] was used in the same manner as in Example 1, except that dipentaerythritol hexaacrylate BMI-TFSI] and diethoxyacetophenone (DEAP) in a weight ratio of 6.5: 3: 0.5.

Example 4

(DPHA), 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide [1-butyl-3-methylimidazolium iodide] was used in the same manner as in Example 1, except that dipentaerythritol hexaacrylate BMI-TFSI] and diethoxyacetophenone (DEAP) were used at a weight ratio of 1.4: 8.5: 0.1.

Example 5

(DPHA), 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide [1-butyl-3-methylimidazolium iodide] was used in the same manner as in Example 1, except that dipentaerythritol hexaacrylate BMI-TFSI], and diethoxyacetophenone (DEAP) in a weight ratio of 7.2: 2.7: 0.1.

Example 6

(1), dipentaerythritol hexaacrylate (DPHA), ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate [HMI-PF6], diethoxy Acetophenone (DEAP) was used in a weight ratio of 4.9: 5: 0.1.

Example 7

(DPHA), an ionic liquid trihexyl (tetradecyl) phosphonium salt compound {[(C ₆ H ₁₃ ) 3P (C ₁₄ H ₂₉ )] [Cl], and diethoxyacetophenone (DEAP) in a weight ratio of 4.9: 5: 0.1.

Example 8

(DPPA) instead of dipentaerythritol hexaacrylate (DPHA), ionic liquid 1-butyl-3-methylimidazolium (DPPA) in place of dipentaerythritol hexaacrylate Bis (trifluoromethanesulfonyl) imide [BMI-TFSI] and diethoxyacetophenone (DEAP) were used in a weight ratio of 4.9: 5: 0.1.

Example 9

Except that pentaerythritol tetraacrylate (PTA) was used instead of dipentaerythritol hexaacrylate (DPHA) in the same manner as in Example 1, and the ionic liquid 1-butyl-3-methylimidazolium bis (Trifluoromethanesulfonyl) imide [BMI-TFSI] and diethoxyacetophenone (DEAP) were used in a weight ratio of 4.9: 5: 0.1.

Comparative Example 1

Except that 2-hydroxyethyl methacrylate (HEMA) was used instead of dipentaerythritol hexaacrylate (DPHA), 1-butyl-3-methylimidazole was used as the ionic liquid in Example 1, (BMI-TFIS) and diethoxyacetophenone (DEAP) were used in a weight ratio of 4.9: 5: 0.1.

Comparative Example 2

(HEMA) and diethoxyacetophenone (DEAP) in a ratio of 9.9: 0.1 were used in place of dipentaerythritol hexaacrylate (DPHA) in (1) Weight ratio.

Comparative Example 3

(1), a liquid electrolyte in which 1 M LiBF ₄ and γ-butyrolactone (GBL) were dissolved and an ionic liquid 1-butyl-3-methylimidazolium bis Imide [BMI-TFSI] was used in a weight ratio of 5: 5.

Comparative Example 4

The same procedure as in Example 1 was carried out except that only a liquid electrolyte in which 1 M LiBF ₄ and? -Butyrolactone (GBL) were dissolved was used at a ratio of 10 by weight in (1).

Comparative Example 5

Except that trimethylolpropane triacrylate (TMTA) was used in place of dipentaerythritol hexaacrylate (DPHA) in the same manner as in Example 1, and the ionic liquid 1-butyl-3-methylimidazolium bis (Trifluoromethanesulfonyl) imide [BMI-TFSI] and diethoxyacetophenone (DEAP) were used in a weight ratio of 4.9: 5: 0.1.

The composition and content (weight ratio) of the gel polymer electrolyte composition prepared in the above Examples and Comparative Examples are shown in Table 1 below.

division Monomer  Ionic liquid polymerization
Initiator Metal salt
(Li ⁺ , mol / L) Liquid
Electrolyte DPHA DPPA PTA HEMA TMTA Ⅰ Ⅱ Ⅲ DEAP LiBF ₄ LiClO ₄
/ γ-GBL Example 1 1.95 - - - - 8 - - 0.05 One - Example 2 4.9 - - - - 5 - - 0.1 One - Example 3 6.5 - - - - 3 - - 0.5 One - Example 4 1.4 - - - - 8.5 - - 0.1 One - Example 5 7.2 - - - - 2.7 - - 0.1 One - Example 6 4.9 - - - - - 5 - 0.1 One - Example 7 4.9 - - - - - 5 0.1 One - Example 8 - 4.9 - - - 5 - - 0.1 One - Example 9 - - 4.9 - - 5 - - 0.1 One - Comparative Example 1 - - - 4.9 - 5 - - 0.1 One - Comparative Example 2 - - - 9.9 - - - - 0.1 One - Comparative Example 3 - - - - - 5 - - - - 5 Comparative Example 4 - - - - - - - - - - 10 Comparative Example 5 - - - - 4.9 5 - - 0.1 One - DPHA: dipentaerythritol hexaacrylate
DPPA: dipentaerythritol pentaacrylate
PTA: Pentaerythritol tetraacrylate
HEMA: 2-hydroxyethyl methacrylate
TMTA: trimethylolpropane triacrylate
Ionic liquid I: 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, [BMI-TFSI]
Ionic liquid II: 1-hexyl-3-methylimidazolium hexafluorophosphate, [HMI-PF6]
Ionic liquid III: trihexyl (tetradecyl) phosphonium salt compound, [(C ₆ H ₁₃ ) 3 P (C ₁₄ H ₂₉ )] [Cl]
DEAP: Diethoxyacetophenone

Test Example

The polymer electrolyte compositions prepared in Examples and Comparative Examples and the properties of the electrochromic devices using the same were measured by the following methods, and the results are shown in Table 2 below.

1. Ionic conductivity of gel polymer electrolyte

Ion conductivity was measured using a conductivity meter (Inolab multi 740).

<Evaluation Criteria>

⊚: Ionic conductivity <10 ^-5 S / cm

?: 10 ^-5 S / cm? Ion conductivity <5 × 10 ^-6 S / cm

Δ: 5 × 10 ^-6 S / cm ≦ ion conductivity <10 ^-6 S / cm

×: 10 ^-6 S / cm ≦ ion conductivity

2. Polymerization time

Using an infrared spectrometer (FT-IR spectrum), the time at which the curing of the polymer electrolyte composition was completed, for example, the change of the double bonds and the change of the permeability (T) of the polymer electrolyte were measured. The results of Example 6 are shown in Fig.

<Evaluation Criteria>

◎: polymerization time ≤ 60 seconds

○: 60 seconds <polymerization time ≤ 120 seconds

?: 120 seconds <polymerization time? 180 seconds

×: 180 sec <polymerization time

3. Product stability

The stability of the product was confirmed by measuring the electrochromic color of the electrochromic device (coloration 2V 20 sec / decoloration -2V 20 sec) using a response speed meter.

<Evaluation Criteria>

&Amp; cir &amp;: 1000 times &amp;num; C (very good).

○: 500 ≦ electrochromic cycle <1000 times (good).

?: The electrochromic cycle <500 times (normal).

X: No electrochromism (poor).

4. Reflectance (%) at the time of electrochromism (discoloration / discoloration)

The electrochromic (coloring / decoloring) test of the electrochromic device was conducted for 2 hours or longer, and then the reflectance at 400 nm was measured. At this time, it was considered that the reflectance at the time of coloring was 37% or less, and the greater the difference in the reflectance value at the time of coloring / coloring, the better.

division Ion conductivity Polymerization time Product stability Reflectivity (%)
(Coloring / decoloring) Example 1 ◎ △ ◎ 35/68 Example 2 ○ ○ ◎ 28/75 Example 3 ○ ◎ ◎ 33/70 Example 4 ◎ △ ◎ 31/73 Example 5 ○ ◎ ○ 33/70 Example 6 ○ ◎ ◎ 30/72 Example 7 ○ ○ ◎ 31/73 Example 8 ○ ○ ○ 30/68 Example 9 ○ ○ ○ 37/65 Comparative Example 1 △ △ △ 40/60 Comparative Example 2 × △ △ 45/55 Comparative Example 3 ○ × × 41/66 Comparative Example 4 ◎ × × 45/70 Comparative Example 5 △ △ △ 40/63

As shown in Table 2 above, the gel polymer electrolytes of Examples 1 to 9 including the 4- to 6-functional acrylic compound, the ionic liquid, the polymerization initiator and the metal salt exhibited similar ion conductivity as the liquid electrolyte, The polymerization reaction was accelerated and the degree of curing was easy to control and the volume and the volume change due to the shrinkage or swelling were small. Thus, the product and the process stability were excellent and the reflectance characteristic according to the electrochromism was excellent. As shown in Fig. 2 (Example 6), the polymerization degree and the promotion of the polymerization reaction were confirmed through the permeability of the gel polymer electrolyte according to the polymerization time. Particularly, when the weight ratio of the compound to the ionic liquid and the polymerization initiator is 1.5-7: 2.5-8.5: 0.03-1 and the nitrogen-containing ionic liquid is used as the 4- to 6-functional acrylic compound, When used, it was more effective not only in controlling polymerization reaction and hardening but also in other properties.

On the other hand, in Comparative Examples 1 and 2 using an ordinary acrylic monomer, the polymerization time was slow, the polymerization reaction was difficult to control, and shrinkage and swelling occurred due to polymerization, resulting in poor product stability. In Comparative Examples 3 and 4 using liquid electrolytes, the ionic conductivity was good due to its inherent characteristics, but the reflectivity was poor, and the product stability due to long use or breakage was not very good. Also, in Comparative Example 5 using a trifunctional acrylic compound, the overall physical properties did not reach the examples.

10: first electrode 11: substrate for first electrode
12: conductive layer for second electrode 20: second electrode
21: substrate for a second electrode 22: conductive layer for a second electrode
31: Electrochromic material layer of the first electrode
32: Electrochromic material layer of the second electrode
40: Seal material 50: Electrolyte

Claims (12)

4 to 6 functional acrylic compounds, ionic liquids, polymerization initiators and metal salts,
The 4 to 6 functional acrylic compounds are at least one selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (2);
[Chemical Formula 1]

(2)

(Wherein R ₁ to R ₆ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,

or

, And four or more of R &_lt; ₁ &gt; to R &_lt; _{6 &}

; R ₇ to R ₁₀ are

ego; R ₁₁ is a hydrogen atom or an alkyl group having 1-6 carbon atoms),
Wherein the ionic liquid is selected from the group consisting of ammonium, imidazolium, oxazolium, piperidinium, pyrazinium, pyrazolium, pyridazinium, pyridinium, pyrimidinium, pyrrolidinium, pyrrolinium, Triazolium and a cation selected from the group consisting of F ^- , Cl ^- , Br ^- , I ^- , NO ₃ ^- , (CN) ₂ N ^- , BF ₄ ^- , ClO ₄ ^- , RSO ₃ ^- , RCOO ^- or a phenyl group having a carbon number of 1-9 and R is an alkyl group), ₆ PF ^-, (CF _{3) 2 4} PF ^-, (CF _{3) 3 3} PF ^-, (CF _{3) 4 2} PF ^-, (CF ₃₎ PF ₅ ^{- _{, (CF 3) 6 P -}} , (CF 3 SO 3 -) 2, (CF 2 CF 2 SO 3 -) 2, (C 2 F 5 SO 2) 2 N -, (CF 3 SO 3) 2 N - _{, (CF 3 SO 2) (} CF 3 CO) N -, CF 3 CF 2 (CF 3) 2 CO -, (CF 3 SO 2) 2 CH -, (SF 5) 3 C -, (CF 3 SO 2 a combination of an anion selected from the group consisting of ^{_{-) 3 C -, CF 3}} (CF 2) 7 SO 3 -, CF 3 COO -, C 3 F 7 COO -, CF 3 SO 3 - and C ₄ F ₉ SO ₃ Lt; / RTI &gt;
4 to 6 functional acrylic compounds, ionic liquid and polymerization initiator is 1.5-7: 2.5-8.5: 0.03-1 (by weight based on solid content).
delete [4] The composition according to claim 1, wherein the 4- to 6-functional acrylic compound is selected from the group consisting of ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate By weight of the gel polymer electrolyte composition for electrochromic devices.
The gel polymer electrolyte composition for an electrochromic device according to claim 3, wherein the 4- to 6-functional acrylic compound is dipentaerythritol hexaacrylate.
delete The gel polymer electrolyte composition for electrochromic devices according to claim 1, wherein the weight ratio (based on solid content) of the 4- to 6-functional acrylic compound, ionic liquid and polymerization initiator is 4.5-5.2: 4.7-5.4: 0.03-0.3.
The gel polymer electrolyte composition for an electrochromic device according to claim 1, wherein the ionic liquid is a compound in which an ion is combined with a cation containing at least one nitrogen atom and an anion.
delete The gel polymer electrolyte composition for an electrochromic device according to claim 1, wherein the metal salt is an alkali metal salt.
The gel polymer electrolyte composition for an electrochromic device according to claim 1, wherein the metal salt contains the cation of the metal salt at a concentration of 0.5 to 1.5 mol / L.
An electrochromic device comprising a first electrode, a second electrode, an electrochromic material, and an electrolyte formed by photocuring of the gel polymer electrolyte composition for an electrochromic device according to any one of claims 1, 3, 4, 6, 7,
12. The electrochromic device according to claim 11, wherein the electrolyte is in-situ polymerized between the first and second electrodes.

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