KR101781144B1 - Solid polymer electrolyte composition and electrochromic device using the same - Google Patents

Abstract

TECHNICAL FIELD The present invention relates to a solid polymer electrolyte composition and an electrochromic device using the same. More particularly, the present invention relates to a solid polymer electrolyte composition comprising a bifunctional acrylic compound represented by Chemical Formula 1, a polymerization initiator and a metal salt, The present invention relates to a solid polymer electrolyte composition having improved ionic conductivity and excellent response speed while maintaining the advantages of a solid form which is easy to be deformed in structure such as a thin film and a film form without side reactions, and an electrochromic device using the solid polymer electrolyte composition.

Description

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

The present invention relates to a solid polymer electrolyte composition having improved ionic conductivity and securing excellent electrochromic properties, 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 and 32 are laminated on the conductive layers 12 and 22 and are changed in color by the applied electric current. The electrolyte 50 for ion conduction and the sealing material 40 for sealing the electrolyte layer 50, .

As the electrolyte (50), a liquid electrolyte and a solid polymer electrolyte are used.

Liquid electrolytes have the advantage of good ionic conductivity, but they are disadvantageous in that the organic solvent is volatilized and depleted, there is a liquid leakage problem in manufacturing the device, the decolorization rate is slow, and the organic matter is easily decomposed by repeated coloring-decoloring.

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 an electrolyte that solves problems of depletion and decomposition of an electrolyte including an aluminum chloride-1-ethyl-3-methylimidazolium chloride ("AlCl ₃ -EMICl") 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. In addition, the liquid electrolyte is disadvantageous in that it is difficult to maintain the stability of the product due to side reaction with the constituent material or volume change due to polymerization, and thinning and processing in the form of a film is impossible.

Unlike liquid electrolytes, solid electrolytes are environmentally friendly because they do not have the same problems as leakage of liquid, and they can be thinned and processed in film form, making it easy to change the structure of a device in any desired form. On the other hand, There is a disadvantage in that the electrochemical reaction is delayed due to the slow ion diffusion and low ionic conductivity.

U.S. Patent No. 6,667,825 (Dec. 23, 2003). U.S. Patent No. 5,872,602 (Feb.

It is an object of the present invention to provide a solid polymer electrolyte capable of improving the ionic conductivity by maintaining the advantages of a solid electrolyte while accelerating an ion diffusion reaction.

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

1. A solid polymer electrolyte composition comprising a bifunctional acrylic compound represented by the following general formula (1), a polymerization initiator and a metal salt:

(Wherein R ₁ is a substituted or unsubstituted alkylene group having 2 to 6 carbon atoms and R ₂ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms).

2. The bifunctional acrylic compound as described in the above 1, wherein the bifunctional acrylic compound is at least one selected from the group consisting of ethylene glycol di (meth) acrylate, 1,3-propanediol di (meth) acrylate, Wherein the solid polymer electrolyte composition is at least one selected from the group consisting of 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and neopentyl glycol di (meth) acrylate.

3. The bifunctional acrylic compound as defined in claim 1, wherein the bifunctional acrylic compound is 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, Composition.

4. The solid polymer electrolyte composition according to 1 above, wherein the weight ratio of the bifunctional acrylic compound represented by the general formula (1) to the polymerization initiator is 8-9.99: 0.01-2.

5. The solid polymer electrolyte composition according to 1 above, wherein the weight ratio of the bifunctional acrylic compound represented by the general formula (1) and the polymerization initiator is 8.6-9.1: 0.9-1.4.

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

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

8. An electrochromic device comprising a first electrode, a second electrode, an electrochromic material, and an electrolyte formed by photocuring of a solid polymer electrolyte composition according to any one of items 1 to 7 above.

9. The electrochromic device of claim 8, wherein the electrolyte is in-situ polymerized between the first and second electrodes.

In the solid polymer electrolyte composition of the present invention, diffusion of ions such as protons or lithium ions is fast, ion conductivity is improved, and there is no residue when applied to an electrochromic device, and excellent response speed can be secured.

In addition, the solid polymer electrolyte composition of the present invention has a high polymerization reaction rate and easy control of the degree of curing, so that appropriate mechanical strength can be imparted.

In addition, the solid polymer electrolyte composition of the present invention has no problems of depletion of the electrolyte and side reaction between the electrolyte and the constituent material, and it is possible to fabricate the device on various substrates, and it is easy to deform the device such as thin film and film form. It can be simplified.

1 is a cross-sectional view of a general electrochromic device.

The present invention relates to a solid polymer electrolyte composition having improved ionic conductivity and securing excellent electrochromic properties, and an electrochromic device using the same.

Hereinafter, the present invention will be described in detail.

The solid polymer electrolyte composition of the present invention is characterized by containing a bifunctional acrylic compound represented by the general formula (1), a polymerization initiator and a metal salt.

In the present invention, a compound capable of forming a solid polymer electrolyte by polymerization with a polymerization initiator through a photo-curing reaction is characterized in that a bifunctional acrylic compound represented by the general formula (1) is selectively used. The bifunctional acrylic compound represented by the general formula (1) has an oxyalkylene group having a polarity at the center and contains a functional acrylic group at the terminal to improve the ionic conductivity. The polymerization rate is fast, the volume shrinkage and swelling are small In addition, it is possible to easily control the degree of curing, which makes it possible to form a solid polymer electrolyte having an appropriate mechanical strength.

[Chemical Formula 1]

In the formula, R ₁ is a substituted or unsubstituted alkylene group having 2 to 6 carbon atoms in view of solubility, and when R ₁ is substituted, it may be substituted with an alkyl group having 1 to 6 carbon atoms. R ₂ is a hydrogen atom or an alkyl group having 1-6 carbon atoms.

Examples of the bifunctional acrylic monomer represented by the formula (1) include ethylene glycol di (meth) acrylate, 1,3-propanediol di (meth) acrylate, 1,3-butanediol di Butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and neopentyl glycol di (meth) acrylate. These may be used singly or in combination of two or more. Of these, 1,4-butanediol di (meth) acrylate and 1,6-hexanediol di (meth) acrylate are preferred. Here, (meth) acrylate means both acrylate and methacrylate.

A small amount of a vinyl compound may be mixed and used as a compound capable of forming a solid polymer electrolyte by photocuring together with the bifunctional acrylic compound represented by the above formula (1).

The kind of the vinyl compound is not particularly limited, and examples thereof include (meth) acrylonitrile, methyl (meth) acrylate, vinyl ester compound, vinyl chloride, vinylidene chloride, acrylamide, tetrafluoroethylene, vinyl acetate, Ketone, ethylene, styrene, methylstyrene, p-methoxystyrene, p-cyanostyrene, etc. These may be used alone or in admixture of two or more. The vinyl compound may be used in a small amount insofar as the yellowing caused by the polymerization initiator does not occur.

The polymerization initiator is for improving the curing reaction efficiency of the solid 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 compounds include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-hydroxy-2-methyl- 1- [2- (2-hydroxyethoxy ) Phenyl] propan-1-one and its oligomers, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan- 2-dimethylamino-1- (4-morpholinophenyl) butan-1-one.

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- It is also possible to use, for example, bis-imidazole, 10-butyl-2-chloroacridone, 2-ethyl anthraquinone, 9,10-phenanthrenequinone, camphorquinone, methylphenylglyoxylate, benzyldimethylketal, have.

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.

Examples of the polymerization initiator include commercially available products such as Opethoma (Asahi Kogyo Co.), Irgacure, OXE-01 (Ciba), Seid SI-60L, UVI-6990 (Union Carbide), BBI-1C3, MPI -103, TPS-103, DTS-103, NAT-103 and NDS-103 (Midori Chemical).

The bifunctional acrylic compound represented by the general formula (1) and the polymerization initiator are preferably contained in the solid polymer electrolyte composition in a weight ratio (based on solid content) of 8-9.99: 0.01-2, more preferably 8.6-9.1: 0.9-1.4 By weight. At this time, the weight ratio of the bifunctional acrylic compound represented by the general formula (1) to the polymerization initiator is based on the total weight ratio of 10. When the weight ratio does not fall within the above range, for example, when the weight ratio of the bifunctional acrylic compound represented by the general formula (1) is less than 8 or the weight ratio of the polymerization initiator is more than 2, the effect of improving ionic conductivity is insignificant, Or swelling may occur. When the weight ratio of the bifunctional acrylic compound represented by the general formula (1) is more than 9.99 or the weight ratio of the polymerization initiator is less than 0.01, the formation of the solid polymer electrolyte is weak and it is difficult to give proper mechanical strength and leakage problems may occur.

The metal salt is used to provide a metal ion to the solid 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 .

Examples of the metal salt include a cation selected from the group consisting of Li ⁺ , Na ⁺ , K ^+, and Cs ⁺ and a cation selected from the group consisting of F ^- , Cl ^- , Br ^- , I ^- , NO ₃ ^- , (CN) ₂ N ^- , BF ₄ ^{- _{4 -, RSO 3 -, RCOO}} - ( wherein, R is an alkyl group or a phenyl group having a carbon number of ^{_{1-9), PF 6 -, AsF}} 6 -, SbF 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 ^-, and C ₄ F ₉ SO ₃ ^- , are preferable. The alkali metal salt is preferably an alkali metal salt of an anion selected from the group consisting of SO ₃ ^- and C ₄ F ₉ SO ₃ ^- .

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 lithium cations 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 thereof depending on the composition of the electrolyte composition and the kind of the electrochromic material, without affecting other components of the solid polymer electrolyte composition. The metal salt is preferably contained so that the concentration of the cation in the metal salt is 0.5 to 1.5 mol / L based on the total content of the solid polymer electrolyte composition. When the concentration of the cation of the metal salt is less than 0.5 mol / L, the solubility in the solid polymer electrolyte composition is good, but the number of free ions that can be conducted is small, so that it is difficult to exhibit sufficient performance as an electrolyte of the electrochromic device. In addition, when it exceeds 1.5 mol / L, the solid polymer electrolyte composition does not dissolve well and forms ion-paring. That is, after ion dissolution, 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 lowered.

The method for producing the solid polymer electrolyte using the solid 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 a solid polymer electrolyte composition is injected between two electrodes and then polymerized. The in-situ polymerization is easier to handle than controlling the polymerized electrolyte and is useful in the production of an electrochromic device. In addition, there is a good advantage of wetting and contact between the solid polymer electrolyte and the electrode.

Polymerization conditions of the solid 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 solid 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), and the like. , Indium doped zinc oxide (IZO), and zinc oxide (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, 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 by which electrochromism occurs in an electrochromic device containing such an inorganic metal oxide is explained as shown in the following reaction formula (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 ⁺ ; x is any integer).

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

(BDDMA) and 1,2-octanedione-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime) (OXE-01, : 1.3 (based on solid content), and LiPF ₆ (Li ⁺ concentration: 1 mol / L) was added to the total composition amount to prepare a solid 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), a UV sealant was used to produce an electrochromic device intermediate without electrolyte. The solid polymer electrolyte composition prepared in (1) was injected into the prepared intermediate, the injection port was sealed with a UV 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

Except that 1,4-butanediol dimethacrylate (BDDMA) and OXE-01 were used in a weight ratio of 9: 1 (based on solids).

Example 3

Except that 1,4-butanediol dimethacrylate (BDDMA) and OXE-01 were used in a weight ratio (based on solid content) of 8.5: 1.5.

Example 4

The procedure of Example 1 was repeated except that 1,6-hexanediol dimethacrylate (HDDMA) and OXE-01 were used at a weight ratio (based on solid content) of 8.7: 1.3.

Example 5

The procedure of Example 1 was repeated except that 1,6-hexanediol dimethacrylate (HDDMA) and OXE-01 were used at a weight ratio (based on solid content) of 9: 1.

Example 6

The procedure of Example 1 was repeated except that 1,6-hexanediol dimethacrylate (HDDMA) and OXE-01 were used at a weight ratio (based on solid content) of 8.5: 1.5.

Example 7

Except that 1,4-butanediol dimethacrylate (BDDMA) and OXE-01 were used at a weight ratio (based on solid content) of 7.7: 2.3.

Example 8

The procedure of Example 1 was repeated except that 1,4-butanediol dimethacrylate (BDDMA) and OXE-01 were used in a weight ratio of 9.5: 0.5 (based on solids).

Example 9

The procedure of Example 1 was repeated except that 1,4-butanediol dimethacrylate (BDDMA) and OXE-01 were used at a weight ratio of 9.995: 0.005 (based on solids).

Comparative Example 1

2-hydroxyethyl methacrylate (HEMA) and OXE-01 were used in a weight ratio (based on solid content) of 8.7: 1.3.

Comparative Example 2

2-hydroxyethyl methacrylate (HEMA) and OXE-01 were used in a weight ratio of 9: 1 (based on solids).

Comparative Example 3

(BDDMA) and a liquid electrolyte in which 1 M LiClO ₄ was dissolved in? -Butyrolactone (GBL) at a weight ratio of 5: 5 was used in the same manner as in Example 1 except that 1,4-butanediol dimethacrylate Respectively.

Comparative Example 4

Except that only a liquid electrolyte in which 1 M LiClO ₄ was dissolved in? -Butyrolactone (GBL) was used in the same manner as in Example 1.

Comparative Example 5

Tetraethylene glycol dimethacrylate (TEGDMA) and OXE-01 were used in a weight ratio (based on solid content) of 8.7: 1.3.

Comparative Example 6

Except that 1,9-nonanediol dimethacrylate (NDDMA) and OXE-01 were used in a weight ratio (based on solid content) of 8.7: 1.3.

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

division Monomer polymerization
Initiator Metal salt
(Li ⁺ , mol / L) Liquid
Electrolyte BDDMA HDDMA HEMA TEGDMA NDDMA OXE-01 LiPF ₆ LiClO ₄ / γ-GBL Example 1 8.7 - - - - 1.3 One - Example 2 9 - - - - One One - Example 3 8.5 - - - - 1.5 One - Example 4 - 8.7 - - - 1.3 One - Example 5 - 9 - - - One One - Example 6 - 8.5 - - - 1.5 One - Example 7 7.7 - - - - 2.3 One - Example 8 9.5 - - - - 0.5 One - Example 9 9.995 - - - - 0.005 One - Comparative Example 1 - - 8.7 - - 1.3 One - Comparative Example 2 - - 9 - - One One - Comparative Example 3 5 - - - - - - 5 Comparative Example 4 - - - - - - - 10 Comparative Example 5 - - - 8.7 - 1.3 One - Comparative Example 6 - - - - 8.7 1.3 One - BDDMA: 1,4-butanediol dimethacrylate
HDDMA: 1,6-hexanediol dimethacrylate
HEMA: 2-hydroxyethyl methacrylate
TEGDMA: tetraethylene glycol dimethacrylate
NDDMA: 1,9-nonanediol dimethacrylate
OXE-01: 1,2-octanedione-1- [4- (phenylthio) phenyl] -2- (O- benzoyloxime)

Test Example

The physical properties of the polymer electrolyte composition and the electrochromic device prepared in the above Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 2 below.

1. Polymer electrolyte ion conductivity

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

<Evaluation Criteria>

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

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

×: 10 ^-6 S / cm <ion conductivity

2. Polymerization time

The time at which the curing of the polymer electrolyte composition was completed using an infrared spectrometer (FT-IR spectrum), for example, the change in the degree of double bond cleavage and the change in the permeability (T) of the polymer electrolyte was measured according to the following criteria .

<Evaluation Criteria>

◎: polymerization time ≤ 60 seconds

○: 60 seconds <polymerization time ≤ 120 seconds

?: 120 seconds <polymerization time? 180 seconds

×: 180 sec <polymerization time

3. Transparency (%) at electrochromism (coloring / decoloring)

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

division Ion conductivity Polymerization time Permeability (%)
(Coloring / decoloring) Example 1 ○ ◎ 30/70 Example 2 ○ ◎ 31/72 Example 3 ○ ○ 32/71 Example 4 ○ ◎ 31/73 Example 5 ○ ◎ 32/71 Example 6 ○ ○ 33/74 Example 7 △ ○ 38/71 Example 8 ○ ○ 33/71 Example 9 ○ △ 36/71 Comparative Example 1 △ △ 47/62 Comparative Example 2 △ △ 43/66 Comparative Example 3 ○ × 40/72 Comparative Example 4 ○ × 40/69 Comparative Example 5 ○ × 45/69 Comparative Example 6 Electrolyte not formed

As shown in Table 2, the solid polymer electrolytes of Examples 1 to 9 including the bifunctional acrylic compound, the polymerization initiator and the metal salt represented by Formula 1 according to the present invention showed similar ionic conductivity to that of the liquid electrolyte, The polymerization reaction was promoted, the degree of curing was easily controlled, and the electrical conductivity was also excellent. In particular, when the weight ratio of the bifunctional acrylic compound to the polymerization initiator is in the range of 8.6 to 9.1: 0.9 to 1.4, polymerization reaction acceleration and curing are more effectively controlled.

On the other hand, in Comparative Examples 1 and 2 using a conventional monofunctional acrylic monomer, it took a long time to polymerize and the polymerization reaction was difficult to control, and the ionic conductivity was not as good as in the examples. Comparative Examples 3 and 4 using a liquid electrolyte had good ionic conductivity due to their inherent characteristics, but took a long polymerization time and had poor permeability. In Comparative Example 5, which used a different type of bifunctional acrylic compound not represented by the general formula (1), the polymerization time was long and the permeability was poor. In Comparative Example 6 in which the bifunctional acrylic compound having different alkylene groups were used, The solubility was poor and the formation of the electrolyte was difficult.

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 (9)

A first electrode and a second electrode facing each other; And
A solid polymer electrolyte formed by photocuring of a solid polymer electrolyte composition filled between the first electrode and the second electrode, the solid polymer electrolyte composition comprising a monomer composed of a bifunctional acrylic compound represented by Chemical Formula 1, a polymerization initiator and a metal salt, ,
Wherein the ratio of the weight of the monomer constituted of the bifunctional acrylic compound to the weight of the polymerization initiator in the solid polymer electrolyte composition is 6.7 to 9,
[Chemical Formula 1]

(Wherein R ₁ is a substituted or unsubstituted alkylene group having 2 to 6 carbon atoms and R ₂ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms).
The bifunctional acrylic compound according to claim 1, wherein the bifunctional acrylic compound represented by Formula (1) is at least one compound selected from the group consisting of ethylene glycol di (meth) acrylate, 1,3-propanediol di (meth) , At least one selected from the group consisting of 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and neopentyl glycol di (meth) acrylate.
The electrochromic device according to claim 1, wherein the bifunctional acrylic compound represented by Formula 1 is 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, or a mixture thereof.
delete delete The electrochromic device according to claim 1, wherein the metal salt is an alkali metal salt.
The electrochromic device according to claim 1, wherein the concentration of the cation in the metal salt is 0.5 to 1.5 mol / L.
delete The electrochromic device according to claim 1, wherein the solid polymer electrolyte is in-situ polymerized between the first electrode and the second electrode.

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