KR101351846B1 - Semi-ipn type solid polymer electrolyte composition comprising polycarbonate based plasticizer with oligoethyleneglycol side chain - Google Patents

Abstract

The present invention relates to a semi-IPN (interpenetrating polymer network) type solid polymer electrolyte composition containing a polycarbonate-based plasticizer with an oligoethyleneglycol side chain. The solid polymer electrolyte composition of the present invention has high ionic conductivity and excellent electrochemical and thermal stability compared to an existing linear polyethyleneglycol plasticizer at low temperatures by the low crystallinity of an oligoethyleneglycol group introduced to polycarbonate as a side chain, and the movement increase of chains inside a molecule by introducing the side chain. The solid polymer electrolyte composition can be applied as solid polymer electrolyte to a lithium-polymer secondary battery, a dye-sensitized solar cell, and fuel cell. [Reference numerals] (AA) Ionic conductivity (Scm^-1); (BB) Example 2; (CC) Example 3; (DD) Example 4; (EE) Temperature (1000K^-1)

Description

Semi-IPN type solid polymer electrolyte composition comprising polycarbonate based plasticizer with oligoethyleneglycol side chain} containing a polycarbonate plasticizer having oligoethylene glycol as a side chain

The present invention relates to a semi-IPN (interpenetrating polymer network) type solid polymer electrolyte composition containing a polycarbonate plasticizer having oligoethylene glycol as a side chain.

Conventionally, an electrochemical device using a liquid electrolyte has caused stability problems such as leakage possibility and explosion possibility. Therefore, an electrochemical device using a polymer electrolyte has been developed to solve such a problem.

As an electrochemical device using a polymer electrolyte, for example, there is a lithium-polymer battery, which is not only excellent in safety but also has a high charge / discharge efficiency and is economical and can be variously designed. So that the battery can be miniaturized.

In particular, the case of using the polyalkylene oxide (PAO) -based solid polymer which is most widely used as the polymer electrolyte, and the gel polymer electrolyte containing the organic liquid electrolyte in the polymer was of interest as the polymer electrolyte of the lithium secondary battery. In general, efforts have been made to improve the conductivity of a polymer electrolyte by adding a low molecular weight polyalkylene oxide or an organic solvent as a plasticizer in order to improve the conductivity of the polymer electrolyte. However, when the content of the plasticizer is increased, the physical properties of the polymer electrolyte are greatly reduced, and stable gel can not be formed.

In order to overcome this problem, Patent Document 1 discloses a method for preparing a crosslinked polymer electrolyte by curing the composition containing a polyalkylene glycol compound having a functional group that can be chemically crosslinked and mixing an ion conductive liquid and an electrolyte salt by UV or electron beam radiation A method is disclosed.

Patent Document 2 discloses a method of using a phosphate flame retardant additive in a non-aqueous electrolyte solvent in order to improve the thermal safety of a lithium secondary battery.

Since the ionic conductivity of polyethylene (PEO) -based solid polymer electrolytes (SPEs) has been reported (Non-Patent Document 1), recent research trends on solid polymer electrolytes have been described as lithium salts. Studies on the use of PEO-based solid polymer electrolytes as matrices have been conducted. PEO-based solid polymer electrolytes are considered as candidate materials for solid electrolytes for secondary lithium batteries for high energy applications. However, it is not yet used as a commercial product. The reason for this is that the ionic conductivity is still low because the high crystallinity of the PEO-based polymer induces a rigid structure at room temperature to suppress the movement of ions.

In Non-Patent Document 2, a method of improving ion conductivity using a phosphazene ring center and a multi-branched oligo (ethylene oxide) group as a plasticizer is disclosed.

Despite the above-mentioned studies, it is still necessary to develop a PEO-based solid polymer electrolyte sufficient to suppress the reduction of ionic conductivity at room temperature through reduction of crystallinity of PEO.

Accordingly, the present inventors are studying a method of improving the ionic conductivity by reducing the crystallinity of a solid polymer electrolyte composition containing a polyalkylene oxide (PEO) -based compound, while polycarbonate having an oligoethylene glycol as a side chain The present invention was completed by finding that the solid polymer electrolyte composition including the system plasticizer is excellent in ionic conductivity due to low crystallinity even at low temperature.

US Patent No. 4,830,939. US Patent No. 5,830,600.

Polymer, 14 (1973) 589. Macromolecules, 1997, 30, 3184.

An object of the present invention is to provide a solid polymer electrolyte composition comprising a polycarbonate plasticizer having oligoethylene glycol as a side chain.

Another object of the present invention to provide a solid polymer electrolyte thin film comprising the composition.

Still another object of the present invention is to provide a lithium-polymer secondary battery comprising the composition.

Another object of the present invention to provide a dye-sensitized solar cell comprising the composition.

Still another object of the present invention is to provide a fuel cell comprising the composition.

In order to achieve the above object, the present invention is 0.1-95% by weight acrylic crosslinking agent;

0.1-96.8 wt% of a polycarbonate plasticizer represented by Chemical Formula 1;

Lithium salt 3-40% by weight; And

It provides a solid polymer electrolyte composition comprising 0.1-5% by weight of a curable initiator.

[Formula 1]

(In Formula 1, m is a non-zero integer, n is an integer of 1 to 10).

The present invention also provides a solid polymer electrolyte thin film including the solid polymer electrolyte composition.

Furthermore, the present invention provides a lithium-polymer secondary battery comprising a solid polymer electrolyte composition.

In addition, the present invention provides a dye-sensitized solar cell comprising a solid polymer electrolyte composition.

Furthermore, the present invention provides a fuel cell comprising the solid polymer electrolyte composition.

The solid polymer electrolyte composition according to the present invention has a low crystallinity of the oligoethylene glycol group introduced into the side chain of polycarbonate and increases the chain motion in the molecule through the introduction of the side chain, compared to the conventional linear polyethylene glycol plasticizer at low temperature. As well as having high ion conductivity, and excellent in electrochemical and thermal stability, it can be usefully used as a solid polymer electrolyte, such as lithium-polymer secondary battery, dye-sensitized solar cell, fuel cell.

1 is a graph showing the ionic conductivity of an electrolyte obtained by thermosetting the solid polymer electrolyte composition prepared in Examples 2 to 4 of the present invention according to temperature change.

Hereinafter, the present invention will be described in detail.

The present invention is 0.1-95% by weight acrylic crosslinking agent;

0.1-96.8 wt% of a polycarbonate plasticizer represented by Chemical Formula 1;

Lithium salt 3-40% by weight; And

It provides a solid polymer electrolyte composition comprising 0.1-5% by weight of a curable initiator.

(In Formula 1, m is a non-zero integer, n is an integer of 1 to 10).

In the solid polymer electrolyte composition according to the present invention, the acrylic crosslinking agent may be applied as a crosslinking agent in various fields such as to improve thermal stability of ignition or explosion due to the use of an organic solvent or when chemical and electrochemical stability are required. have.

In this case, as the acrylic crosslinking agent, poly (ethylene glycol) diacrylate, poly (ethylene glycol) dimethacrylate, bisphenol A ethoxylate diacrylate, bisphenol A ethoxylate dimethacrylate, dipentaerythritol penta / Hexa-acrylate, tris (2- (acryloxy) ethyl) phosphate and the like can be used.

In addition, the crosslinking agent is contained in the total polymer electrolyte composition in the range of 0.1 to 95% by weight, preferably 1 to 80% by weight, more preferably 3 to 60% by weight. When the content is less than 0.1% by weight, the amount is too small to obtain an effect as a crosslinking agent, and there is a problem that the mechanical properties are lowered. When the content is more than 95% by weight, the ion conductivity is reduced.

The acryl-based crosslinking agent serves to form a three-dimensional network structure of semi-IPN (Interpenetrating Polymer Network) type because the acrylic group is introduced.

Next, in the solid polymer electrolyte composition according to the present invention, the polycarbonate-based plasticizer represented by Chemical Formula 1 may be used alone or in admixture with a non-aqueous polar solvent. It helps to improve conductivity.

In this case, as the non-aqueous polar solvent, alkylene carbonate, alkyl tetrahydrofuran, dioxirane, lactone, acetonitrile and the like may be used alone or in combination. Specific examples thereof include ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxirane, 4,4-dimethyl- ? -butyrolactone, acetonitrile, and the like can be used.

In addition, the plasticizer may be contained in the total polymer electrolyte composition in the range of 0.1 to 96.8% by weight, preferably 0.1 to 90% by weight. In general, the amount of plasticizer included in the polymer electrolyte is directly proportional to the ion conductivity of the polymer electrolyte, but when the content is less than 0.1 wt%, the effect of improving the ion conductivity is insignificant. When the content exceeds 96.8 wt%, the mechanical properties There is a problem that can not be reduced to make a thin film is difficult to apply to battery manufacturing. Therefore, when the above range is maintained, it is possible to produce a thin film having a thickness of 100 mu m or less.

On the other hand, the polycarbonate plasticizer represented by the formula (1) can be prepared by the following method. However, the following preparation method is just one example, and the preparation method, the reaction reagent and the reaction conditions are not limited thereto.

[Reaction Scheme 1]

(In Scheme 1, m is a non-zero integer, n is an integer from 1 to 10).

First, the compound of the formula (5) prepared by tosylation of the terminal hydroxyl group of the oligoethylene glycol derivative represented by the formula (4), and the diol group of the compound represented by the formula (2) The compound represented by Chemical Formula 6 may be prepared by performing a coupling reaction of the compound of Chemical Formula 3 (Step 2), which is protected with benzaldehyde. Next, the deprotected diol group of the compound represented by Formula 6 is deprotected (step 4), and the deprotected diol group is 1,1'-carbonyldiimidazole of Formula 10. Using to prepare a compound represented by the formula (8) activated to the carbonate group (step 5). Under the benzyl alcohol represented by the formula (11) as a catalyst, a polycarbonate-based plasticizer of the formula (1) according to the present invention can be prepared by performing a polymerization reaction of the compound of the formula (8) including a carbonate group.

Next, in the solid polymer electrolyte composition according to the present invention, the lithium salt is not particularly limited to those commonly used in the art for preparing a polymer electrolyte. LiClO ₄ , LiCF ₃ SO ₃ , LiBF ₄ , LiPF ₆ , LiAsF ₆ , Li (CF ₃ SO ₂ ) ₂ N and the like can be specifically used as the lithium salt generally used conventionally.

At this time, the lithium salt is contained in the total polymer electrolyte composition in the range of 3 to 40% by weight, preferably 5 to 25% by weight, but if necessary, the amount may be adjusted by an appropriate mixing ratio. If the content is less than 3% by weight, the concentration of lithium ions is too low to be suitable as an electrolyte. If the content is more than 40% by weight, there is a problem of solubility of the lithium salt and reduction of ionic conductivity.

Next, in the solid polymer electrolyte composition according to the present invention, all the initiators such as photocurable and thermosetting, which are generally used in the art, may be used as the curable initiator.

The photocurable initiator is ethyl benzoin ether, isopropyl benzoin ether, α-methylbenzoin ethyl ether, benzoin phenyl ether, α-acyl oxime ester, α, α-diethoxyacetophenone, 1,1-di Chloroacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one [Darocur 1173 from Ciba Geigy], 1-hydroxycyclohexylphenyl ketone [Shiba Kaigi Irgacure 184, Darocure 1116, Igacure 907, anthraquinone, 2-ethylanthraquinone, 2-chloroanthraquinone, thioxanthone, isopropyl thioxanthone, and chlorothioxanthone (Ciba Geigy) , Benzophenone, p-chlorobenzophenone, benzyl benzoate, benzoylbenzoate, mycloketone and the like can be used.

In addition, the thermosetting initiators are benzoyl peroxide, di-tert-butyl peroxide, di-tert-amyl peroxide, α-cumyl peroxy neodecanoate, α-cumyl peroxy neopeptanoate, t-amyl Peroxyneodecanoate, di- (2-ethylhexyl) peroxy-dicarbonate, t-amylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl-2,5 bis (2 -Ethyl-hexanoylperoxy) hexane, dibenzoylperoxide, t-amylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, 1,1-di- (t- Amylperoxy) cyclohexane, 1,1-di- (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-di- (t-butylperoxy) cyclohexane, t-butylper Oxyacetate, t-butylperoxybenzoate, t-amylperoxybenzoate, t-butylperoxybenzoate, ethyl 3,3-di- (t-amylperoxy) butyrate, ethyl 3,3-di- (t-butylperoxy) butyrate, dicumyl peroxide, etc. Peroxide initiator or 1,1'-azobis (cyclohexanecarbonitrile), 2,2'-azobis (2-methylpropionamidine) dihydrochloride, 4,4'-azobis (4-cyano Compounds such as valeric acid) can be used.

At this time, the curable initiator is contained in the total polymer electrolyte composition in the range of 0.1 to 5% by weight, when the content is less than 0.1% by weight, there is a problem that the effect of the initiator cannot be obtained, and when it exceeds 5% by weight There is a problem that the unreacted curing initiator after curing reduces the performance of the battery.

On the other hand, the curing initiator may be appropriately adjusted according to the mixing ratio of the other components used simultaneously in the solid polymer electrolyte composition.

The present invention also provides an electrolyte thin film comprising the solid polymer electrolyte composition.

An exemplary process for preparing an electrolyte thin film using the solid polymer electrolyte composition will be described in more detail below, but the present invention is not limited thereto.

First, the plasticizer and the lithium salt according to the present invention are put into a container at an appropriate ratio and stirred with a stirrer to prepare a solution. Then, an acrylic crosslinking agent is added and mixed with each other. When a curing initiator is added to this mixed solution and stirred, a mixed solution for preparing a solid polymer electrolyte is prepared. The solution prepared above is coated on a support such as a glass plate, polyethylene-based vinyl or commercial Mylar film or a battery electrode to an appropriate thickness to undergo a curing reaction under an irradiation of electron beam, ultraviolet ray, gamma ray or the like.

Another manufacturing method for obtaining a film of a constant thickness, is to apply the composition mixture on the support, fixed to the thickness control spacer on both ends of the support and then cover the other support thereon, the curing irradiator Or curing reaction using a heat source to produce a solid polymer electrolyte thin film.

Further, the present invention provides a lithium-polymer secondary battery comprising the solid polymer electrolyte composition.

Another example of application of the polymer electrolyte composition of the solid polymer electrolyte composition according to the present invention will be described in detail with reference to an example process of preparing a polymer electrolyte of a lithium polymer secondary battery, but the present invention is not limited thereto.

The lithium-polymer secondary battery is composed of a cathode, an electrolyte and a cathode. Lithium metal oxides such as LiCoO ₂ and LiNiO ₂ are mainly used as the anode. Examples of the cathode include carbon-based materials such as MCMB and MPCF, Metal or the like as a material. The electrolytic solution containing the crosslinking agent, the plasticizer, the lithium salt and the curing initiator of the present invention is prepared, and then the electrolyte solution is poured into the substrate to form a film having a certain thickness. This film is dried for a predetermined time to obtain a polymer electrolyte membrane.

The lithium-polymer secondary battery can be manufactured by any of the methods commonly used in the field of the present invention in addition to the above-described methods.

In addition, the present invention provides a dye-sensitized solar cell comprising the solid polymer electrolyte composition.

First, the plasticizer and the lithium salt according to the present invention are put into a container at an appropriate ratio and stirred with a stirrer to prepare a solution. Then, an acrylic crosslinking agent is added and mixed with each other. When a curing initiator is added to this mixed solution and stirred, a mixed solution for preparing a solid polymer electrolyte is prepared. The composition mixture prepared above is coated on a conductive transparent glass substrate (photoelectrode) and dried. In this case, the polymer electrolyte having a constant polymer concentration may be cast once on the photoelectrode (single layer coating method), or the polymer electrolyte having a different polymer concentration may be cast on the photoelectrode sequentially (multilayer coating method). A dye-sensitized solar cell is manufactured by stacking a glass substrate on which a counter electrode is formed on the polymer electrolyte layer prepared above. As described above, as the counter electrode, a conductive transparent glass substrate coated with only platinum may be used, or a conductive transparent glass substrate sequentially coated with platinum and a conductive polymer may be used.

The method of manufacturing a dye-sensitized solar cell can be prepared by any method commonly used in the field of the present invention, in addition to the method described above.

Furthermore, the present invention provides a fuel cell comprising the solid polymer electrolyte composition.

The fuel cell includes a cathode and a membrane electrode assembly in which a polymer electrolyte membrane is interposed between the anode and the anode, and generates electrical energy through an electrochemical reaction between the cathode and the anode.

In this case, as the polymer electrolyte membrane of the membrane electrode assembly, a polymer electrolyte membrane including a polycarbonate plasticizer having an oligoethylene glycol according to the present invention as a side chain is used, and preferably a hydrogen ion conductive polymer fuel cell (PEMFC) Or direct methanol fuel cells (DMFC), more preferably direct methanol fuel cells (DMFC).

Here, the cathode and the anode are not particularly limited in the present invention, and any of those known in the art can be used.

As described above, the solid polymer electrolyte composition according to the present invention is a conventional linear polyethylene glycol even at low temperature due to low crystallinity of the oligoethylene glycol group introduced into the side chain of polycarbonate and increased chain motion in the molecule through side chain introduction. In addition to having a high ion conductivity compared to the lycol plasticizer, and excellent electrochemical and thermal stability, it can be usefully used as a solid polymer electrolyte, such as lithium-polymer secondary battery, dye-sensitized solar cell, fuel cell (experimental example) 1 and Experimental Example 2).

Hereinafter, the present invention will be described in more detail by the following Preparation Examples and Examples.

However, the following Preparation Examples and Examples are merely to illustrate the present invention, the contents of the present invention is not limited by the following Examples.

< Manufacturing example  1> Polycarbonate series  Preparation of Plasticizers (Compounds 1a, 1b)

[Reaction Scheme 1]

(In Scheme 1, m is a non-zero integer, n is an integer of 1 to 10.)

Step 1: Preparation of Compound (3)

Trimethyloilethane (24 g, 199 mmol) and p-toluenesulfonic acid (1.2 g, 0.0315 mmol) were dissolved in tetrahydrofuran (THF, 250 mL), and benzaldehyde (40.6 mL, 400 mmol) was dissolved in 0 ° C. Was slowly added dropwise. After that, the reaction proceeds at room temperature for 24 hours. The solvent in the reaction solution was distilled under reduced pressure, and the resultant was recrystallized from dichloromethane and hexane to obtain the target compound (28 g, 68%) as a white solid.

¹ H NMR (CDCl ₃ ), δ (ppm): 7.49-7.35 (m, 5H), 5.43 (s, 1H), 4.05 (d, 2H), 3.87 (d, 2H), 3.64 (d, 2H), 1.94 (s, 1 H), 0.79 (s, 3 H)

Step 2: Preparation of Compounds (5a, 5b)

Triethyleneglycol monomethylether (4a) (20 g, 121.8 mmol) or tetraethyleneglycol monomethylether (4b) (20 g, 96.04 mmol) was dissolved in 40 mL of 5 M NaOH solution and p- Tolueneselfonyl chloride (27.9 g, 146.16 mmol) was slowly added dropwise at 0 ° C. The reaction solution was stirred at room temperature for 24 hours, and then extracted three times using dichloromethane and distilled water. The solvent of the extracted dichloromethane layer was distilled under reduced pressure to obtain a target compound (5a) or (5b) (5a: 37 g, 95%, 5b: 34 g, 98%) as a colorless liquid without further purification.

Compound (5a): ¹ H NMR (CDCl ₃ ), δ (ppm): 7.80 (d, 2H), 7.34 (d, 2H), 4.16 (t, 2H), 3.69 (t, 2H), 3.63-3.59 ( m, 6H), 3.55-3.52 (m, 2H), 3.37 (s, 3H), 2.45 (s, 3H);

Compound (5b): ¹ H NMR (CDCl ₃ ), δ (ppm): 7.81 (d, 2H), 7.34 (d, 2H), 4.16 (t, 2H), 3.70-3.53 (m, 14H), 3.38 ( s, 3H), 2.45 (s, 3H).

Step 3: Preparation of Compounds (6a, 6b)

Compound (3) (10 g, 48.60 mmol) obtained in step 1 above was dissolved in tetrahydrofuran (240 mL) and sodium hydride (NaH, 2.3 g, 97.20 mmol) was added all at once at 0 ° C. The reaction solution was stirred at 60 ° C. for 5 hours, then compound 5a (16.82 g, 53.40 mmol) or (5b) (15.7 g, 43.22 mmol) obtained in step 2 was added. Thereafter, the reaction solution was stirred at 60 ° C. for 12 hours, and a small amount of distilled water was added to terminate the reaction. After filtering the terminated reaction solution, the filtered filtrate was extracted three times with dichloromethane and distilled water. The extracted dichloromethane layer was collected and distilled under reduced pressure, and then purified by column chromatography using ethyl acetate and hexane to give the title compound (6a) or (6b) (6a: 15.5 g, 91%, 6b: 15 g, 78 %) Was obtained as a colorless liquid. Since each compound contains cis and trans isomers, it was confirmed that the compound was synthesized through molecular weight of the compound through EI-MS without confirmation through NMR.

Compound 6a: EI-MS: m / z = 354;

Compound 6b: EI-MS: m / z = 398.

Step 4: Preparation of Compounds (7a, 7b)

Compound (6a) (14 g, 39.50 mmol) or (6b) (12 g, 30.11 mmol) obtained in step 3 was dissolved in methanol (50 mL), and then 50 mL of 5 M hydrochloric acid solution was added. The reaction solution was stirred at 120 ° C. for 12 hours, and then extracted three times with dichloromethane and distilled water. The dichloromethane layer extracted was distilled under reduced pressure, and column chromatography was performed with methanol and ethyl acetate to give the title compound (7a) or (7b) (7a: 6.8 g, 65%, 7b: 6.1 g, 65%) as a colorless liquid. )

Compound (7a): ¹ H NMR (CDCl ₃ ), δ (ppm): 3.66-3.53 (m, 18H), 3.38 (s, 3H), 2.98 (t, 2H), 0.79 (s, 3H);

Compound (7b): ¹ H NMR (CDCl ₃ ), δ (ppm): 3.74-3.53 (m, 22H), 3.38 (s, 3H), 0.75 (s, 3H).

Step 5: Preparation of Compounds (8a, 8b)

Compound (7a) (2.00 g, 7.51 mmol) or (7b) (2.40 g, 7.73 mmol) obtained in step 4 was dissolved in dichloromethane (10 mL), and then 1,1'-carbonyldi at 0 ° C. A solution of imidazole (1.46 g, 9.01 mmol) in dichloromethane (30 mL) was slowly added dropwise. The reaction solution was stirred at room temperature for 24 hours, and then the solvent was removed by distillation under reduced pressure. Column chromatography was carried out with ethyl acetate to obtain the title compound (8a) or (8b) (8a: 1.47 g, 66%. 8b: 1.52 g, 58%) as a colorless liquid.

Compound (8a): ¹ H NMR (CDCl ₃ ), δ (ppm): 4.36 (d, 2H), 4.06 (d, 2H), 3.66-3.62 (m, 10H), 3.56-3.54 (m, 2H), 3.44 (s, 2 H), 3.37 (s, 3 H), 1.09 (s, 3 H);

Compound (8b): ¹ H NMR (CDCl ₃ ), δ (ppm): 4.37 (d, 2H), 4.07 (d, 2H), 3.66-3.61 (m, 14H), 3.57-3.54 (m, 2H), 3.45 (s, 2 H), 3.38 (s, 3 H), 1.10 (s, 3 H).

Step 6: Preparation of Compounds (1a, 1b)

To compound (8a) (1.0 g, 3.42 mmol) or (8b) (1.0 g, 2.97 mmol) obtained in step 5 was added calcium hydride (CaH ₂ ) and dissolved in dichloromethane to remove water for about a day. . The concentration of dichloromethane was maintained at 1 M and benzyl alcohol (0.0037 g, 0.034 mmol) and DBU (0.0052 g, 0.034 mmol) were added. The reaction solution was stirred at room temperature for 3 days, and then a small amount of acetic acid was added to terminate the reaction. The reaction product was distilled under reduced pressure to remove the solvent, and 2-propanol: hexane = 1: 9 mixed solution was added to remove impurities by sedimentation. Thereafter, the target compound (1a) or (1b) (1a: 0.9 g, 90%, 1b: 0.85 g, 85%) of a high viscosity liquid was obtained without further purification.

Compound (1a): ¹ H NMR (CDCl ₃ ), δ (ppm): 4.08 (s, 4H), 3.65-3.55 (m, 12H), 3.38-3.37 (m, 5H), 1.01 (s, 3H);

Compound (1b): ¹ H NMR (CDCl ₃ ), δ (ppm): 4.08 (s, 4H), 3.66-3.55 (m, 16H), 3.38-3.36 (m, 5H), 1.01 (s, 3H).

< Example  1> Preparation of Solid Polymer Electrolyte 1

Plasticizer: compound (1a) prepared in Example 1 (0.1 g, 0.086 mmol); And

Lithium salt: LiN (SO ₂ CF ₃ ) ₂ (0.030 g, 0.104 mmol) was stirred for 1 hour at room temperature until a uniform mixture to prepare a solid polymer electrolyte. At this time, the molar ratio of [EO] / [Li] is 20, which means that the content of lithium salt decreases as the value of [EO] / [Li] increases (wherein [EO] is the number of moles of ethylene oxide present in the electrolyte). And [Li] is the number of moles of lithium ions).

< Example  2> semi - IPN  Type solid polymer electrolyte 2

Plasticizer: compound (1a) prepared in Example 1 (0.21 g, 0.181 mmol);

Lithium salt: LiN (SO ₂ CF ₃ ) ₂ (0.085 g, 0.296 mmol);

Crosslinker: polyethyleneglycol diacrylate 575 (0.09 g, 0.156 mmol); And

Thermosetting Initiator: t-amylperoxybenzoate (APO) (0.012 g, 0.058 mmol) was stirred for 1 hour at room temperature until a uniform mixture to prepare a solid polymer electrolyte. At this time, the molar ratio of [EO] / [Li] is 20, which means that the content of lithium salt decreases as the value of [EO] / [Li] increases (wherein [EO] is the number of moles of ethylene oxide present in the electrolyte). And [Li] is the number of moles of lithium ions).

< Example  3> semi - IPN  Preparation of Type Solid Polymer Electrolyte 3

Plasticizer: compound (1a) prepared in Example 1 (0.15 g, 0.129 mmol);

Lithium salt: LiN (SO ₂ CF ₃ ) ₂ (0.083 g, 0.289 mmol);

Crosslinker: polyethyleneglycol diacrylate 575 (0.15 g, 0.261 mmol); And

Thermosetting Initiator: t-amylperoxybenzoate (APO) (0.012 g, 0.058 mmol) was stirred for 1 hour at room temperature until a uniform mixture to prepare a solid polymer electrolyte. At this time, the molar ratio of [EO] / [Li] is 20, which means that the content of lithium salt decreases as the value of [EO] / [Li] increases (wherein [EO] is the number of moles of ethylene oxide present in the electrolyte). And [Li] is the number of moles of lithium ions).

< Experimental Example  1> Evaluation of Ion Conductivity with Temperature Change of Solid Polymer Electrolyte

In order to evaluate the ionic conductivity according to the temperature change of the solid polymer electrolyte prepared in Examples 1 to 3 according to the present invention, the experiment was performed as follows.

After injecting the solid polymer electrolyte composition prepared in each of the above examples into a band-shaped conductive glass substrate or a lithium-copper foil, it is thermally cured and polymerized, dried sufficiently, and then between the band-type or sandwich-type electrodes in an argon atmosphere. AC impedance was measured, and the measured value was analyzed by a frequency response analyzer (manufacturer: Zahner Elekrik, model name: IM6) to obtain a complex impedance analysis method. The band-type electrode was used by attaching a masking tape having a width of about 1 mm to the center of the conductive glass (ITO) at intervals of about 2 cm, placing it in an etching solution, and then etching and washing. In addition, the result of measuring the ion conductivity according to the temperature change of the solid polymer electrolyte using the compound (1a) as a plasticizer according to the present invention is shown in FIG.

As shown in FIG. 1, the solid polymer electrolytes prepared in Examples 1 to 3 show typical Vogel-Tamman-Fulcher (VTF) relationship behavior. Unlike conventional linear plasticizers that have low ionic conductivity at low temperatures due to their crystallinity, polycarbonate plasticizers of the formula (1a) having oligoethylene glycol as a side chain have no crystallinity and thus ion conductivity at low temperatures. Is superior to the linear plasticizer.

Therefore, the electrolyte obtained by curing the solid polymer electrolyte composition according to the present invention has excellent ionic conductivity, and thus can be effectively used as a solid polymer electrolyte such as a lithium-polymer secondary battery, a dye-sensitized solar cell, and a fuel cell.

< Experimental Example  2> Evaluation of Ionic Conductivity at Room Temperature of Solid Polymer Electrolyte

In order to evaluate the ionic conductivity of the solid polymer electrolyte prepared in Examples 1 to 3 according to the present invention at room temperature, experiments were performed as follows.

In order to determine the ionic conductivity at room temperature, the solid polymer electrolyte composition prepared in each of the above examples was injected into a band-shaped conductive glass substrate or a lithium-copper foil, and then thermally cured and polymerized, dried sufficiently, and then at 20 ° C. And AC impedance between the band-type or sandwich-type electrodes in an argon atmosphere at 30 ° C., and the measured values were analyzed by a frequency response analyzer (manufacturer: Zahner Elekrik, model name: IM6) to obtain a complex impedance analysis method. The band-type electrode was used by attaching a masking tape having a width of about 1 mm to the center of the conductive glass (ITO) at intervals of about 2 cm, placing it in an etching solution, and then etching and washing. The ion conductivity measurement results are shown in Table 1 below.

Plasticizer: Crosslinking agent weight ratio 20 ℃ ion conductivity 30 ℃ ion conductivity Example 1 100: 0 3.78 × 10 ^-6 9.67 × 10 ^-6 Example 2 70:30 1.61 × 10 ^-5 4.70 × 10 ^-5 Example 3 50:50 2.10 × 10 ^-6 5.98 × 10 ^-6

As shown in Table 1, the semi-IPN type solid polymer electrolyte containing a polycarbonate plasticizer having oligoethylene glycol as a side chain has an ion conductivity of 10 ^-5 to 10 ^-6 S / cm at room temperature. It can be seen that. In particular, the solid polymer electrolyte having a weight ratio of 70:30 of the plasticizer and the crosslinking agent prepared in Example 2 shows high ionic conductivity of 4.70 × 10 ⁻⁵ S / cm at 30 ° C.

Therefore, since the electrolyte obtained by curing the solid polymer electrolyte composition according to the present invention has excellent ion conductivity, it may be usefully used as a solid polymer electrolyte such as a lithium-polymer secondary battery, a dye-sensitized solar cell, a fuel cell, and the like.

Claims (10)

0.1-95% by weight acrylic crosslinking agent;
0.1-96.8 wt% of a polycarbonate plasticizer represented by Chemical Formula 1;
Lithium salt 3-40% by weight; And
A solid polymer electrolyte composition comprising 0.1-5% by weight of a curable initiator:
[Chemical Formula 1]

(In Formula 1, m is a non-zero integer, n is an integer of 1 to 10).
The method of claim 1,
The lithium salts are _{LiClO 4, LiCF 3 SO 3,} LiBF 4, LiPF 6, LiAsF 6 and Li (CF ₃ SO ₂₎ A solid polymer electrolyte composition, characterized in that at least one member selected from the group consisting of N _2.
The method of claim 1,
The curable initiator is a solid polymer electrolyte composition, characterized in that at least one selected from the group consisting of a photocurable initiator and a thermosetting initiator.
The method of claim 3,
The photocurable initiator is ethylbenzoin ether, isopropylbenzoin ether, α-methylbenzoin ethyl ether, benzoin phenyl ether, α-acyl oxime ester, α, α-diethoxy acetophenone, 1,1-dichloroaceto Phenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, anthraquinone, 2-ethyl anthraquinone, 2-chloroanthraquinone, thioxanthone, isopropyl A solid polymer electrolyte composition, characterized in that at least one selected from the group consisting of thioxanthone, chlorothioxanthone, benzophenone, p-chlorobenzophenone, benzyl benzoate, benzoyl benzoate and mickle ketone.
The method of claim 3,
The thermosetting initiator may be at least one selected from the group consisting of benzoyl peroxide, di-tert-butyl peroxide, di-tert-amyl peroxide,? -Cumyl peroxyneodecanoate,? -Cumyl peroxyneepeptanoate, Butyl peroxypivalate, 2,5-dimethyl-2,5 bis (2-ethylhexyl) peroxy-dicarbonate, t-amyl peroxypivalate, Butyl peroxy-2-ethylhexanoate, 1,1-di- (t-amyl peroxide) hexane, dibenzoyl peroxide, t- Oxy) cyclohexane, 1,1-di- (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-di- (t- butylperoxy) cyclohexane, t- butyl peroxybenzoate, t-butyl peroxybenzoate, t-butyl peroxybenzoate, ethyl 3,3-di- (t-amylperoxy) butyrate, ethyl 3,3-di- (t -Butylperoxy) butyrate, dicumyl peroxide, 1,1'-azo Azobis (4-cyanobalenoic acid), bis (cyclohexanecarbonyl), 2,2'-azobis (2-methylpropionamidine) dihydrochloride and 4,4'- By weight based on the total weight of the solid polymer electrolyte composition.
The method of claim 1,
Wherein the solid polymer electrolyte obtained by applying heat or light to the solid polymer electrolyte composition forms a semi-IPN (Interpenetrating Polymer Network) type three-dimensional network structure.
A solid polymer electrolyte membrane comprising the solid polymer electrolyte composition of claim 1.
A lithium-polymer secondary battery comprising the solid polymer electrolyte composition of claim 1.
A dye-sensitized solar cell comprising the solid polymer electrolyte composition of claim 1.
A fuel cell comprising the solid polymer electrolyte composition of claim 1.

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