KR20130013991A - Gel polymer electrolyte composition and electrochromic device using the same - Google Patents

Abstract

PURPOSE: A gel polymer electrolyte composition is provided to easily control reaction rate and hardness, and to have excellent reaction rate by improving ion conductivity. CONSTITUTION: A gel polymer electrolyte composition comprises a polymer indicated in chemical formula 1, a trifunctional acrylic compound, an ionic liquid, a polymerization initiator, and metal salt. In the chemical formula 1: R1 is a C1-6 alkoxy group; R2 is hydrogen, a C1-6 alkyl group, or -CH2-O-C(=O)C(R3)=CH2; R3 is hydrogen or a C1-6 alkyl group; and n is an integer from 2-70. The weight average molecular weight of the polymer indicated in chemical formula 1 is 400-3,000. The weight ratio of the polymer indicated in chemical formula 1 and the trifunctional acrylic compound, an ionic liquid and a polymerization initiator is 4.5-8:1.5-4.5:0.3-2.

Description

Gel polymer electrolyte composition and electrochromic device using same {GEL POLYMER ELECTROLYTE COMPOSITION AND ELECTROCHROMIC DEVICE USING THE SAME}

The present invention relates to a gel polymer electrolyte composition and an electrochromic device using the same, which can maintain the stability of a manufacturing process and a product, and can ensure excellent electrochromic properties by improving ion conductivity.

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.

In general, as shown in FIG. 1, the electrochromic device includes transparent conductive layers 12 and 22 formed on substrates 11 and 21 and transparent to first and second electrodes 10 and 20 to which an electric field is applied. An electrochromic material layers 31 and 32 stacked on the conductive layers 12 and 22 and changed in color by an applied current, and include an electrolyte 50 for ion conduction and an encapsulant 40 for sealing the electrolyte 50. It consists of.

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

Unlike liquid electrolytes, solid electrolytes have no problems such as liquid leakage and are environmentally friendly, have excellent stability in electrochromic devices, and can be thinned and processed in the form of films, making it easy to change the structure of the device in any desired form. On the other hand, the ion diffusion reaction of protons or lithium ions is slow, the ion conductivity is low, the electrochromic reaction is delayed, and the performance is low, making it difficult to commercialize.

Liquid electrolytes are depleted due to volatilization of organic solvents, liquid leakage problems during device fabrication, and slow discoloration and repeated discoloration-discoloration. In addition, it is difficult to maintain the stability of the product due to volume change by side reactions or polymerization with the device constituent material, there is a disadvantage that the thin film and processing of the film form is impossible. To solve this problem, U.S. Patent No. 6,667,825 discloses a liquid electrolyte that includes an ionic liquid to improve stability and lifespan.However, an ionic liquid is used as an electrolyte in a liquid form. It was still difficult to apply to film-like processing and the like. In addition, US Pat. No. 5,872,602 discloses an electrolyte which solves the problem of depletion and decomposition of an electrolyte, including AlCl ₃ -EMICl (aluminum chloride-1-ethyl-3-methylimidazolium chloride) ionic liquid. In case of exposure to a small amount of water or oxygen, the toxic gas is released and the reactivity with the organic-inorganic compound added in a small amount in the electrolyte is very high, in particular, there is a disadvantage that easily decomposes at 150 ℃ or more. In addition, the liquid electrolyte has a disadvantage in that it is difficult to maintain product stability due to volume change by side reaction or polymerization with the device constituent materials, and thin film and film processing are impossible.

US Patent No. 6,667,825 (Dec. 23, 2003). US Patent No. 5,872,602 (1999.02.16).

An object of the present invention is to provide a gel polymer electrolyte that can easily control the reaction rate and the degree of curing during the polymerization, improve the ionic conductivity and maintain the stability of the production process and products due to the small volume change.

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

1. A gel polymer electrolyte composition comprising a polymer, a trifunctional acrylic compound, an ionic liquid, a polymerization initiator, and a metal salt represented by Formula 1 below:

이며, R₃는 수소 원자 또는 탄소수 1-6의 알킬기이고, n은 2-70인 정수임).(Wherein R ₁ is an alkoxy group having 1-6 carbon atoms, R ₂ is a hydrogen atom, an alkyl group having 1-6 carbon atoms or

R ₃ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n is an integer of 2-70.

2. In the above 1, wherein the polymer represented by Formula 1 has a weight average molecular weight of 400 to 3,000 gel polymer electrolyte composition.

3. In the above 1, R ₁ is a methoxy group gel polymer electrolyte composition.

4. In the above 1, wherein the trifunctional acrylic compound is a gel polymer electrolyte composition represented by the following formula (2):

이고, R₅는 수소 원자, 히드록시기 또는 탄소수 1-6의 히드록시알킬기이며, R₆은 탄소수 1-6의 알킬기임).(Wherein R ₄ is

R ₅ is a hydrogen atom, a hydroxy group or a hydroxyalkyl group having 1 to ₆ carbon atoms, and R ₆ is an alkyl group having 1 to ₆ carbon atoms.

5. In the above 4, the trifunctional acrylic compound represented by the formula (2) is a group consisting of pentaerythritol tri (meth) acrylate, hexaerythritol tri (meth) acrylate and hepterythritol tri (meth) acrylate At least one gel polymer electrolyte composition selected from.

6. In the above 4, wherein the trifunctional acrylic compound represented by the formula (2) is a pentaerythritol tri (meth) acrylate gel polymer electrolyte composition.

7. In the above 1, the weight ratio of the polymer represented by the formula (1) and the trifunctional acrylic compound is 3-6: 4-7 gel polymer electrolyte composition.

8. The gel polymer electrolyte composition according to the above 1, wherein the weight ratio of the polymer and the trifunctional acrylic compound represented by Chemical Formula 1 and the ionic liquid and the polymerization initiator is 4.5-8: 1.5-4.5: 0.3-2.

9. The gel polymer electrolyte composition according to the above 1, wherein the weight ratio of the polymer represented by the formula (1) and the trifunctional acrylic compound, the ionic liquid and the polymerization initiator is 5.5-6.5: 2.5-3.5: 0.5-1.5.

10. The gel polymer electrolyte composition according to 1 above, wherein the ionic liquid is a compound in which an anion is ion-bonded with a cation containing one or more nitrogen atoms.

11. In above 1, the ionic liquid is 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 (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 ^-, selected from the group consisting of Gel polymer electrolyte composition consisting of a combination of anions.

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

13. In the above 1, wherein the metal salt is a gel polymer electrolyte composition comprising a concentration of cations in the metal salt is 0.5 to 1.5 mol / L.

14. An electrochromic device comprising an electrolyte formed by photocuring a first electrode, a second electrode, an electrochromic material, and the gel polymer electrolyte composition of any one of 1 to 13.

15. The electrochromic device of claim 14, wherein the electrolyte is in-situ polymerized between the first and second electrodes.

The gel polymer electrolyte composition of the present invention has an improved ionic conductivity above the level of the liquid electrolyte to ensure excellent electrochromic properties when applied to the electrochromic device with a good response speed.

In addition, the gel polymer electrolyte composition of the present invention has a fast polymerization reaction rate and can easily control the degree of curing to impart an appropriate mechanical strength, and there is little shrinkage or expansion of the volume during polymerization, and thus, it is easy to maintain stability of the manufacturing process and products.

In addition, the gel polymer electrolyte composition of the present invention has no problem of depletion of electrolytes and leakage reactions and side reactions between device components, and the device can be fabricated on various substrates. It can be simplified.

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

The present invention relates to a gel polymer electrolyte composition and an electrochromic device using the same, which can maintain the stability of a manufacturing process and a product, and can ensure excellent electrochromic properties by improving ion conductivity.

Hereinafter, the present invention will be described in detail.

The gel polymer electrolyte composition of the present invention is characterized by comprising a polymer represented by the formula (1), a trifunctional acrylic compound, an ionic liquid, a polymerization initiator and a metal salt.

In the present invention, as 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, in particular, the polymer represented by the formula (1) and the trifunctional acrylic compound are used in combination. There is this.

The polymer represented by the formula (1) contains alkoxy groups having polarity at one end and functional acrylic groups at the other end, so that the reaction rate is high during polymerization, the volume shrinkage and expansion is small, and the degree of curing can be easily controlled. It allows the formation of gel polymer electrolytes endowed with mechanical strength.

[Formula 1]

이며; R₃은 수소 원자 또는 탄소수 1-6의 알킬기이다. 또한, n은 2-70인 정수이다.In formula, R <_1> is a C1-C6 alkoxy group, Preferably it is a methoxy group; R ₂ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or

; R ₃ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. In addition, n is an integer of 2-70.

The polymer represented by the formula (1) preferably has a weight average molecular weight (Mw) of 400 to 3,000. If the weight average molecular weight is less than 400, leakage may occur due to insufficient role of the backbone of the solid electrolyte. If the weight average molecular weight is greater than 3,000, the ion conductivity may be lowered and the solubility may be lowered.

인 화합물이 바람직하다.In the polymer represented by the formula (1), R ₁ is a methoxy group, and R ₂ is

Phosphorus compounds are preferred.

The trifunctional acrylic compound is a compound capable of forming a gel polymer electrolyte by polymerization by a polymerization initiator and a photocuring reaction together with the polymer represented by Chemical Formula 1, and can further improve ionic conductivity and have a fast reaction rate during polymerization. Curing degree can be easily adjusted.

Although the kind of trifunctional acrylic compound is not specifically limited, Especially trifunctional acrylic compound represented by General formula (2) is preferable. The trifunctional acryl-based compound represented by the formula (2) is more advantageous in achieving a desired effect in the present invention by containing a hydrogen atom or a hydroxyl group having a polarity at one end and a functional acrylic group at the other end.

[Formula 2]

이고, R₅는 수소 원자, 히드록시기 또는 탄소수 1-6의 히드록시알킬기, 바람직하게 히드록시메틸기인 것이 좋다. 또한, R₆은 탄소수 1-6의 알킬기이다.Wherein R ₄ is

R ₅ is a hydrogen atom, a hydroxy group or a hydroxyalkyl group having 1 to 6 carbon atoms, preferably a hydroxymethyl group. R ₆ is an alkyl group having 1 to ₆ carbon atoms.

Examples of the trifunctional acrylic monomer represented by Chemical Formula 2 include pentaerythritol tri (meth) acrylate, hexaerythritol tri (meth) acrylate, heptaerythritol tri (meth) acrylate, and the like. It can mix and use 2 or more types. Among these, pentaerythritol tri (meth) acrylate is preferable. Here, (meth) acrylate means both acrylate and methacrylate.

The polymer represented by the formula (1) and the trifunctional acrylic compound are preferably included in the gel polymer electrolyte composition in a weight ratio of 3-6: 4-7 (based on solids). At this time, the weight ratio of the polymer represented by the formula (1) and the trifunctional acrylic compound is based on their total weight ratio 10. When the weight ratio does not fall within the above range, for example, when the weight ratio of the polymer represented by Formula 1 is less than 3 or the weight ratio of the trifunctional acrylic compound is greater than 7, the content of the polymer may be relatively low, resulting in poor stability with voltage. . In addition, when the weight ratio of the polymer represented by Formula 1 is greater than 7 or the weight ratio of the trifunctional acrylic compound is less than 4, ionic conductivity may decrease.

A small amount of a vinyl compound may be used as a compound capable of forming a gel polymer electrolyte by photocuring together with the polymer represented by Formula 1 and a trifunctional acrylic compound.

The type of 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, and methyl vinyl. Ketone, ethylene, styrene, methyl styrene, p-methoxy styrene, p-cyano styrene, and the like. These may be used alone or in combination of two or more thereof. The vinyl compound may be used in a small amount in a range in which yellowing does not occur by a polymerization initiator.

Ionic liquids are ionic compounds formed by ionic bonds of cations and anions, and are ionic salts that have the property of being present as a liquid at temperatures of up to 100 ° C. In particular, the ionic liquid in the present invention preferably contains at least one nitrogen atom. The free radicals generated by the nitrogen atoms can promote the rate of polymerization reaction for the formation of the gel polymer electrolyte to suppress shrinkage and expansion and impart appropriate mechanical strength.

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

As cations constituting the ionic liquid, ammonium, imidazolium, oxazolium, piperidinium, and pyrazi represented by the formulas (a) to (n), respectively, Pyrazinium, pyrazolium, pyridazinium, pyridinium, pyrimidinium, pyrrolidinium, pyrrolidinium, pyrrolinium, pyrrolium , Thiazolium, triazolium, and the like.

(3)

(Wherein, R ₇ to R ₁₂ are each independently an alkyl group having 1 to 9 carbon atoms or a phenyl group).

As an anion constituting the ionic liquid is ^{F -, Cl -, Br -} , I -, NO 3 -, (CN) 2 N -, BF 4 -, ClO 4 -, RSO 3 - ( wherein, R is C 1 -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 can be used individually or in mixture of 2 or more types.

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

Acetophenone compounds include diethoxy acetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-hydroxy-2-methyl-1- [2- (2-hydroxyethoxy ) Phenyl] propan-1-one and oligomers thereof, 1-hydroxycyclohexylphenylketone, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan-1-one, 2-benzyl- 2-dimethylamino-1- (4-morpholinophenyl) butan-1-one etc. are mentioned.

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

Examples of the benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3 ', 4,4'-tetra (t-butylper Oxycarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, etc. are mentioned.

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.

In addition, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2 as an optical radical generating agent '-Biimidazole, 10-butyl-2-chloroacridone, 2-ethylanthraquinone, 9,10-phenanthrenequinone, camphorquinone, methylphenylglyoxylate, benzyldimethyl ketal, titanocene compound and the like may also be used. 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.

In addition, as polymerization initiators, commercially available products such as Optoma (Asahi telephone company), Irgacure, OXE-01 (Shiba Corporation), Seaid SI-60L, UVI-6990 (Union Carbide Corporation), BBI-1C3, MPI -103, TPS-103, DTS-103, NAT-103, NDS-103 (Midori Chemical Co., Ltd.), etc. can also be used.

The polymer represented by the formula (1) and the trifunctional acrylic compound, the ionic liquid and the polymerization initiator are preferably included in the gel polymer electrolyte composition as 4.5-8: 1.5-4.5: 0.3-2 (based on solids), and more preferably. Makes 5.5-6.5: 2.5-3.5: 0.5-1.5 At this time, the weight ratio of the polymer represented by the formula (1), the trifunctional acrylic compound, the ionic liquid and the polymerization initiator is based on the total weight ratio 10. When the weight ratio does not fall within the above range, for example, when the weight ratio of the polymer represented by the formula (1) and the trifunctional acrylic compound is less than 4.5 or the weight ratio of the ionic liquid is more than 4.5, the gel polymer electrolyte is weakly formed and the appropriate mechanical strength is imparted. Is difficult. In addition, when the weight ratio of the polymer represented by the formula (1) and the trifunctional acrylic compound is greater than 8 or the weight ratio of the ionic liquid is less than 1.5, the effect of improving the ionic conductivity may be insignificant and the electrochromic speed may be reduced. In addition, in these ranges, the synergistic effect of the ionic conductivity due to the combination of the polymer represented by the formula (1), the trifunctional acrylic compound, and the ionic liquid and the provision of an appropriate mechanical strength to the gel polymer electrolyte are difficult.

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 .

Metal salts include Li ^+, Na ^+, K ^+, and cations selected from the group consisting of Cs ⁺ and ^{F -, Cl -, Br -} , I -, NO 3 -, (CN) 2 N -, BF 4 -, ClO _{^{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 Alkali metal salts consisting of ionic bonds of anions selected from the group consisting of SO ₃ ^- and C ₄ F ₉ SO ₃ ^- are preferred.

In particular, when inorganic metals such as WO ₃ and NiO are used as the electrochromic materials of the electrochromic device, it is preferable to use alkali metal salts containing lithium cations such as LiClO ₄ , LiAsF ₆ , LiSbF ₆ , LiPF6 or LiBF ₄ . More preferably, it is LiPF ₆ or LiBF ₄ .

The metal salt can be used by appropriately adjusting the content thereof according to 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 included so that the concentration of cation in the metal salt is 0.5 to 1.5 mol / L based on the total content of 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. In addition, when more than 1.5 mol / L dissolution in the gel polymer electrolyte composition is not well formed to form an ion pair (ion-paring), that is, after the ions are dissolved and separated by + /-should be the movement of the ions In an ion pair or ion aggregation state, movement becomes impossible, resulting in a small number of free ions and a low conductivity.

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.

The polymerization conditions of the gel polymer electrolyte by photocuring are not particularly limited, and may be carried out with a conventional light irradiation amount, for example, within a polymerization time of 10 minutes or less.

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. The substrate may include glass, transparent plastic (polymer), and the like, and conductive materials for forming a transparent conductive layer may include indium doped tin oxide (ITO), antimony doped tin oxide (ATO), and fluorine doped tin oxide (FTO). , Indium doped zinc oxide (IZO), ZnO, and the like. 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.

Among electrochromic materials, WO ₃ is a material that is colored by a reduction reaction, and NiO is a material that is colored by an oxidation reaction. The electrochemical mechanism in which the electrochromic color occurs in the electrochromic device including the inorganic metal oxide is described as in Scheme 1 below. 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 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.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but these examples are merely illustrative of the present invention and are not intended to limit the scope of the appended claims. It is apparent to those skilled in the art that various changes and modifications can be made to the present invention, and such modifications and changes belong to the appended claims.

Example

Example 1

(1) gel polymer electrolyte composition

The methoxy polyethylene glycol methacrylate having Mw of 600 and pentaerythritol triacrylate (PETA) were mixed at a weight ratio of 5: 5. Stomach mixture and Ionic liquid 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide [BMI-TFSI], 1,2-octanedione-1- [4- (phenylthio) phenyl] -2 -(O-benzoyloxime) (OXE-01, Ciba) was mixed at a weight ratio of 6.0: 3.3: 0.7 (based on solids) and LiPF ₆ (Li ⁺ concentration: 1 mol / L) was added to the total content of the composition Gel polymer electrolyte compositions were prepared.

(2) 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 portion of the edges of the working electrode and the counter electrode (electrolyte inlet), an electrochromic device intermediate was prepared by bonding the UV sealant to the absence of an electrolyte. The gel polymer electrolyte composition prepared in (1) was injected into the prepared intermediate, the injection hole was sealed with a UV sealant, and then irradiated with an ultraviolet (UV) exposure machine for 1 minute to produce an electrochromic device by in-situ polymerization.

Example 2

In the same manner as in Example 1, Mw of 600 methoxy polyethylene glycol methacrylate and pentaerythritol triacrylate (PETA) was used in a weight ratio of 4: 6.

Example 3

In the same manner as in Example 1, a mixture, an ionic liquid and a polymerization initiator were used in a weight ratio (based on solids) of 6.3: 3.1: 0.6.

Example 4

The same procedure as in Example 2 was carried out, but the mixture, the ionic liquid and the polymerization initiator were used in a weight ratio (based on solids) of 6.3: 3.1: 0.6.

Example 5

The same procedure as in Example 1, except that the mixture, the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate [HMI-PF ₆ ] and the polymerization initiator 5.7: 3.3: 1.0 by weight (based on solids) Used as.

Example 6

In the same manner as in Example 1, Mw of methoxy polyethylene glycol methacrylate and pentaerythritol triacrylate (PETA) was used in a weight ratio of 2.5: 7.5.

Example 7

In the same manner as in Example 1, Mw of 600 methoxy polyethylene glycol methacrylate and pentaerythritol triacrylate (PETA) was used in a weight ratio of 7.5: 2.5.

Example 8

In the same manner as in Example 1, a mixture, an ionic liquid and a polymerization initiator were used in a weight ratio (based on solids) of 8.2: 1.5: 0.3.

Example 9

In the same manner as in Example 1, a mixture, an ionic liquid and a polymerization initiator were used in a weight ratio of 4.7: 5.0: 0.3 (based on solids).

Example 10

In the same manner as in Example 1, trimethylolpropane triacrylate (TMPTA) was used instead of pentaerythritol triacrylate (PETA).

Example 11

The same procedure as in Example 1, except that methoxy polyethylene glycol methacrylate Mw of 350 was used.

Example 12

The same procedure as in Example 1, except that methoxy polyethylene glycol methacrylate having a Mw of 3,200 was used.

Comparative Example 1

The same procedure as in Example 1, except that polyethylene glycol polymer having a Mw of 600 was used.

Comparative Example 2

The same procedure as in Example 1, except that polyethylene glycol polymer having a Mw of 1,000 was used.

Comparative Example 3

The same procedure as in Example 1, except that polyethylene glycol dimethacrylate polymer having a Mw of 200 was used.

Comparative Example 4

In the same manner as in Example 1, a liquid electrolyte in which 1 M LiClO ₄ was dissolved in pentaerythritol triacrylate (PETA) and γ-butyrolactone (GBL) was used at a weight ratio of 5: 5.

Comparative Example 5

The same procedure as in Example 1 was carried out, except that only a liquid electrolyte in which 1M LiClO ₄ was dissolved in γ-butyrolactone (GBL) was used.

Comparative example  6

It carried out similarly to Example 1, but did not use pentaerythritol triacrylate (PETA).

Comparative example  7

The same procedure as in Example 1, except that methoxy polyethylene glycol methacrylate having a Mw of 600 was not used.

Comparative Example 8

In the same manner as in Example 1 except that methoxy polyethylene glycol methacrylate having Mw of 600 was used, and trimethylolpropane triacrylate (TMPTA) was used instead of pentaerythritol triacrylate (PETA).

Comparative example  9

In the same manner as in Example 1, 2-hydroxyethyl methacrylate (HEMA) was used instead of pentaerythritol triacrylate (PETA).

The components and contents (weight ratios) of the gel polymer electrolyte compositions prepared in Examples and Comparative Examples are shown in Table 1 below.

division polymer
(A) Monomer
(B) A: B
(Weight ratio) Ionic Liquid (C) A + B: C: OXE-01
(Weight ratio) Metal salt Liquid
Electrolyte Kinds Kinds Kinds Example 1 A1 B1 5: 5 C1 6.0: 3.3: 0.7 One - Example 2 A1 B1 4: 6 C1 6.0: 3.3: 0.7 One - Example 3 A1 B1 5: 5 C1 6.3: 3.1: 0.6 One - Example 4 A1 B1 4: 6 C1 6.3: 3.1: 0.6 One - Example 5 A1 B1 5: 5 C2 5.7: 3.3: 1.0 One - Example 6 A1 B1 2.5: 7.5 C1 6.0: 3.3: 0.7 One - Example 7 A1 B1 7.5: 2.5 C1 6.0: 3.3: 0.7 One - Example 8 A1 B1 5: 5 C1 8.2: 1.5: 0.3 One - Example 9 A1 B1 5: 5 C1 4.7: 5.0: 0.3 One - Example 10 A1 B2 5: 5 C1 6.0: 3.3: 0.7 One - Example 11 A2 B1 5: 5 C1 6.0: 3.3: 0.7 One - Example 12 A3 B1 5: 5 C1 6.0: 3.3: 0.7 One - Comparative Example 1 A4 B1 5: 5 C1 6.0: 3.3: 0.7 One - Comparative Example 2 A5 B1 5: 5 C1 6.0: 3.3: 0.7 One - Comparative Example 3 A6 B1 5: 5 C1 6.0: 3.3: 0.7 One - Comparative Example 4 - B1 0:10 - 5 - 5 Comparative Example 5 - - - - - - 10 Comparative Example 6 A1 - 10: 0 C1 6.0: 3.3: 0.7 One - Comparative Example 7 - B1 0:10 C1 6.0: 3.3: 0.7 One - Comparative Example 8 - B2 0:10 C1 6.0: 3.3: 0.7 One - Comparative Example 9 A1 B3 5: 5 C1 6.0: 3.3: 0.7 One - A1: methoxy polyethylene glycol methacrylate having Mw of 600
A2: methoxy polyethylene glycol methacrylate having Mw of 350
A3: methoxy polyethylene glycol methacrylate having Mw of 3,200
A4: polyethyleneglycol polymer having Mw of 600
A5: polyethyleneglycol polymer having Mw of 1,000
A6: polyethylene glycol dimethacrylate polymer having a Mw of 200
B1: pentaerythritol triacrylate (PETA)
B2: trimethylolpropane triacrylate (TMPTA)
B3: 2-hydroxyethyl methacrylate (HEMA)
C1: 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, [BMI-TFSI]
C2: 1-hexyl-3-methylimidazolium hexafluorophosphate, [HMI-PF ₆ ]
OXE-01: 1,2-octanedione-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime) (Shiba Corporation)
Metal salt (Li ⁺ , mol / L): LiPF ₆
Liquid Electrolyte: LiClO ₄ / γ-GBL

Test Example

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

1.Ion Conductivity of Polymer Electrolyte

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

<Evaluation Criteria>

◎: ion conductivity <1 × 10 ^-5 S / cm

○: 1 × 10 ^-5 S / cm ≤ ion conductivity <5 × 10 ^-5 S / cm

Δ: 5 × 10 ^-5 S / cm ≤ ion conductivity ≤ 1 × 10 ^-6 S / cm

×: 1 × 10 ^-6 S / cm <ion conductivity

2. polymerization time

Infrared spectroscopy (FT-IR spectra) was used to measure the time at which curing of the polymer electrolyte composition was completed, such as elimination of double bonds and polymerization (T) change of the polymer electrolyte, based on the following criteria: .

<Evaluation Criteria>

◎: polymerization time ≤ 60 seconds

○: 60 seconds <polymerization time ≤ 120 seconds

△: 120 seconds <polymerization time ≤ 180 seconds

×: 180 seconds <polymerization time

3. Product stability

The electrochromic (coloring 2V 20 sec / coloring -2V 20 sec) cycle of the electrochromic device was measured using a response meter, and the product stability was evaluated based on the following criteria.

<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. Permeability (%) when electrochromic (colored / discolored)

After the electrochromic (coloring / discoloring) test of the electrochromic device was carried out for 2 hours or more, the transmittance at 400 nm was measured. At this time, the transmittance at the time of coloring was 37% or less, and it was considered that it is so good that the difference of the transmittance | permeability at the time of coloring / coloring is large.

division Ion conductivity Polymerization time Product stability Permeability (%)
(Coloring / decoloring) Example 1 ○ ◎ ◎ 30/71 Example 2 ○ ◎ ◎ 31/70 Example 3 ○ ◎ ◎ 30/69 Example 4 ○ ◎ ◎ 32/69 Example 5 ○ ○ ◎ 31/71 Example 6 ◎ ○ ○ 35/70 Example 7 ○ ○ ◎ 34/70 Example 8 ○ ○ ○ 32/71 Example 9 ◎ ○ ○ 33/73 Example 10 ○ ○ ○ 33/72 Example 11 ○ ○ ○ 35/70 Example 12 ○ ○ ○ 33/70 Comparative Example 1 △ △ △ 46/62 Comparative Example 2 △ △ △ 45/64 Comparative Example 3 △ △ △ 43/71 Comparative Example 4 ○ × × 39/66 Comparative Example 5 ○ × × 38/69 Comparative Example 6 ○ ○ △ 39/71 Comparative Example 7 ○ ○ △ 38/68 Comparative Example 8 ○ △ △ 38/70 Comparative Example 9 △ × × 45/65

As shown in Table 2, the gel polymer electrolytes of Examples 1 to 12 including the polymer represented by the formula (1), the trifunctional monomer, the ionic liquid, the polymerization initiator, and the metal salt according to the present invention have similar ionic conductivity as the liquid electrolyte. In addition, the polymerization reaction according to the photocuring was promoted and the degree of curing was not easily controlled, and the volume change due to shrinkage or expansion was small, so that the product and process stability were excellent, and the permeability characteristics due to the electrochromic color were also excellent. In particular, when the weight average molecular weight of the polymer represented by the formula (1) is 400-3,000, when the weight ratio of the polymer represented by the formula (1) and the trifunctional monomer is 3-6: 4-7, If the trifunctional monomer is a monomer represented by the formula (2) was more effective in all physical properties.

On the other hand, Comparative Examples 1 to 3 using other types of polymers not represented by Formula 1 are The polymerization time was long and the control of the polymerization reaction was difficult, and the ionic conductivity did not reach the examples. In addition, Comparative Examples 4 and 5 using the liquid electrolyte had good ionic conductivity due to its inherent properties, but poor permeability and very poor product stability due to prolonged use or breakage. In addition, Comparative Example 6, which does not use the trifunctional monomer, Comparative Examples 7 and 8, which do not use the polymer represented by the formula (1) has good ionic conductivity, but other physical properties did not reach the examples. In addition, Comparative Example 9, which used a conventional monofunctional acrylic monomer instead of trifunctional, did not have good ionic conductivity.

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 (15)

A gel polymer electrolyte composition comprising a polymer, a trifunctional acrylic compound, an ionic liquid, a polymerization initiator, and a metal salt represented by Formula 1 below:
[Formula 1]

(Wherein R ₁ is an alkoxy group having 1-6 carbon atoms, R ₂ is a hydrogen atom, an alkyl group having 1-6 carbon atoms or

R ₃ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n is an integer of 2-70.
The gel polymer electrolyte composition of claim 1, wherein the polymer represented by Formula 1 has a weight average molecular weight of 400 to 3,000.
The gel polymer electrolyte composition according to claim 1, wherein R ₁ is a methoxy group.
The gel polymer electrolyte composition of claim 1, wherein the trifunctional acrylic compound is represented by the following Chemical Formula 2:
(2)

(Wherein R ₄ is

R ₅ is a hydrogen atom, a hydroxy group or a hydroxyalkyl group having 1 to ₆ carbon atoms, and R ₆ is an alkyl group having 1 to ₆ carbon atoms.
The trifunctional acrylic compound represented by the formula (2) is selected from the group consisting of pentaerythritol tri (meth) acrylate, hexaerythritol tri (meth) acrylate, and heptaerythritol tri (meth) acrylate. At least one gel polymer electrolyte composition.
The gel polymer electrolyte composition according to claim 4, wherein the trifunctional acrylic compound represented by the formula (2) is pentaerythritol tri (meth) acrylate.
The gel polymer electrolyte composition according to claim 1, wherein the weight ratio of the polymer represented by the formula (1) and the trifunctional acrylic compound is 3-6: 4-7.
The gel polymer electrolyte composition according to claim 1, wherein the weight ratio of the polymer represented by the general formula (1), the trifunctional acrylic compound, and the ionic liquid and the polymerization initiator is 4.5-8: 1.5-4.5: 0.3-2.
The gel polymer electrolyte composition according to claim 1, wherein the weight ratio of the polymer represented by the general formula (1), the trifunctional acrylic compound, and the ionic liquid and the polymerization initiator is 5.5-6.5: 2.5-3.5: 0.5-1.5.
The gel polymer electrolyte composition of claim 1, wherein the ionic liquid is a compound in which an anion is ion-bonded with a cation containing one or more nitrogen atoms.
The method of claim 1, wherein the ionic liquid is ammonium, imidazolium, oxazolium, piperidinium, pyrazinium, pyrazolium, pyridazinium, pyridinium, pyrimidinium, pyrrolidinium, pyrrolinium, pyrrolium , with a cation selected from the group consisting of thiazolium and ^{triazolium, F -, Cl -, Br} -, I -, NO 3 -, (CN) 2 N -, BF 4 -, ClO 4 -, RSO 3 -, RCOO ^-, PF ₆ (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 ^- of anion selected from the group consisting of Gel polymer electrolyte composition consisting of a bond.
The gel polymer electrolyte composition of claim 1, wherein the metal salt is an alkali metal salt.
The gel polymer electrolyte composition according to claim 1, wherein the metal salt is contained so that the concentration of cation in the metal salt is 0.5 to 1.5 mol / L.
An electrochromic device comprising an electrolyte formed by photocuring a first electrode, a second electrode, an electrochromic material, and the gel polymer electrolyte composition of claim 1.
The electrochromic device of claim 14, wherein the electrolyte is in-situ polymerized between the first and second electrodes.

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