KR20010037163A - Heat-Crosslinkable Polysiloxane Electrolytes Composition And Method For Preparing Solid Polymer Electrolytic Film By Using The Same - Google Patents

Abstract

PURPOSE: Provided are a heat crosslinkable polysiloxane electrolytic composition and a method for preparing solid high molecular electrolytic thin film which has reinforced mechanical physical properties such as thin film forming property and compression strength, easily introduces low molecular weight polyalkylene oxide, has improved ion conductivity at room temperature and show good adhesive strength with electrode. CONSTITUTION: The polysiloxane electrolytic composition comprises: (i) 10-80 wt.% of polyhydromethylsiloxane having a polyalkylene oxide group represented by the formula(1), wherein each R1 and R2 is H or methyl group, X is -O- or -OCOO- group, each x and y is an integer of 0-20 and each p and q is an integer of 0-1,000; (ii) 1-60 wt.% of cross-linking agent having three allyl groups represented by the formula(2), wherein R is linear or cyclic aliphatic and aromatic compound having 1-10 carbon atoms or hetero alicyclic compound such as triazine and isocyanurate, X is -O- or -OCOO- group and each x, y and z is an integer of 0-20; (iii) polyalkyleneglycol dialkylether which is an oligomer or a polymer for improving dissociation of lithium salt and conductivity of lithium ion and represented by the formula(3), wherein each R1 and R2 is liner or branched alkyl group having 1-10 carbon atoms, each X, Y and Z is H or methyl group and each p, q and r an integer of 0-20; (iv) 3-30 wt.% of lithium salt; and (v) 0.001-1 wt.% of platinum catalyst for hardening.

Description

Heat-Crosslinkable Polysiloxane Electrolytes Composition And Method For Preparing Solid Polymer Electrolytic Film By Using The Same}

The present invention provides a crosslinking polysiloxane comprising a novel crosslinking agent having three reactive groups including an ethylene glycol oligomer, a polyhydromethylsiloxane polymer having a polyalkylene oxide group introduced therein, a lithium salt, a polyalkylene glycol dialkyl ether and a platinum catalyst. And it relates to a method for producing a solid polymer electrolyte thin film using the same. The cross-linked solid polysiloxane electrolyte composition according to the present invention is a large-capacity lithium polymer applicable to electric power storage devices and electric vehicles as well as small lithium polymer secondary batteries applied to devices such as mobile information terminals and camcorders such as mobile phones and laptop computers. It can be applied to electrochemical devices such as secondary batteries, electrochromic devices and sensors.

The electrochemical device using the solid electrolyte has no problem of leaking the solution compared to the electrochemical device using the conventional liquid electrolyte, and can provide a chemical battery having a high charge and discharge efficiency. It can be manufactured in the form of a thin film, and has been an object of intensive research and development in the past because it can be manufactured in a small size. In particular, a lithium-polymer battery using a polyalkylene oxide (PAO) -based polymer solid electrolyte has been widely recognized for its importance as it can produce a battery having greatly improved energy density.

PAO-based polymer solid electrolytes were described in 1975 British Journal 7 vol. 319. V. First discovered by PV Wright, 1978. After M. Armand was first called an ion-conducting polymer, its application to electrochemical devices has been expanding. Typical solid polymer electrolytes consist of a complex of lithium salts with polymers with electron-donating atoms such as oxygen, nitrogen, and phosphorus. The most representative example is a complex of polyethylene oxide (PEO) and a lithium salt, which is difficult to apply to room temperature operation because of its low ion conductivity value of 10 ^-8 S / cm at room temperature. Can be used as a power source.

The PAO-based solid polymer electrolyte has high crystallinity at room temperature and thus has limited molecular chain motion, and thus has very low ionic conductivity at room temperature. In order to increase the molecular chain motion of the solid polymer electrolyte, it is necessary to minimize the crystalline region present in the polymer structure to increase the amorphous region. As part of this research, studies have been made to prepare a comb-type polymer by introducing PAO having a relatively short molecular length as a side chain, or to prepare a solid polymer electrolyte having a network structure by introducing and cross-linking one or more functional groups capable of crosslinking to PAO end groups. It became.

Blonsky et al. Described polybismethoxyethoxyethoxyphosphazine [J. Am. Chem. Soc., 106 (1984) 6845], Pantaloni et al., Polyethoxyethoxyethoxyvinyl ether [Electrochim. And report on the applicability of comb-like solid polymer electrolytes to Acta, 34 (1989) 635.

See also US Pat. No. 4,830,939 and document ″ J. Electrochemm. Soc., 145, 1521 (1998) ″ includes acrylates of polyalkylene glycols with unsaturated functional groups and is cured by UV or electron-beam radiation from a mixture of ion conductive liquids and electrolyte salts. A method for producing a crosslinked polymer electrolyte is described.

In particular, polysiloxane-based polymers have unique flexibility and low glass transition temperature, and thus are expected to improve molecular chain motion. Proceeded [Macroromol. Chem. Rapid Commun., 7 (1986) 115 ″; U.S. Patent Nos. 4,673,718, 4,766,185, 5,227,043, 5,440,011, and Japanese Patent Application Laid-Open No. 5-290616.

However, these comb-shaped and reticular solid polymer electrolytes have a conductivity of about 10 ^-5 to 10 ^-4 S / cm at room temperature, and have disadvantages of poor physical properties when molded into a film.

In order to solve this problem, Abraham et al prepared a solid polymer electrolyte in which a low molecular weight polyethylene oxide was added to a vinyldifluoride-hexafluoropropane copolymer to prepare an electrolyte having somewhat improved conductivity (Chem. Mater., 9 (1997) 1978), the present inventors have also enhanced mechanical properties by using a crosslinking agent in which three ethylene glycol acrylates are introduced at the center of a cyclic alkyl or hetero alkyl molecule (Korean Patent Application No. 99-24732). Reference).

SUMMARY OF THE INVENTION An object of the present invention is to provide a solid polymer electrolyte composition having a polyhydromethylsiloxane polymer as a basic skeleton structure and a polyalkylene oxide group acting as a side chain and a crosslinking agent.

Another object of the present invention is to use a cross-linking agent in which three reactors are introduced at the center of a cyclic or linear molecule in place of a cross-linking agent having two reactors, thereby enabling a three-dimensional network structure to provide mechanical properties such as thin film formability and compressive strength. The present invention provides a method for preparing an electrolyte thin film having enhanced physical properties and easy introduction of low molecular weight polyalkylene oxide, thereby improving ion conductivity at room temperature.

1 is an infrared spectral spectrum before and after curing of a solid polymer electrolyte composition;

2 is a graph evaluating the electrochemical stability of the polymer electrolyte by scanning voltammetry.

The present invention provides a solid polymer electrolyte having high ion conducting properties at room temperature and a method of preparing the same.

The composition of the solid polymer electrolyte composition according to the present invention is as follows based on the total weight of the solid polymer electrolyte:

(1) 10 to 80% by weight of polyhydromethylsiloxane in which the polyalkylene oxide group represented by the following general formula (1) is introduced side by side:

Wherein R ₁ and R ₂ are H or a methyl group; X is or Group; x and y are each an integer of 0 to 20; And p and q are each an integer from 0 to 1000;

(2) 1 to 60 wt% of a crosslinking agent having three allyl groups at the terminal represented by the following general formula (2):

Wherein R is a C ₁ -C ₁₀ linear or cyclic aliphatic and aromatic compound or a heterocyclic compound represented by triazine, isocyanurate or the like, X is or And x, y and z are integers from 0 to 20;

(3) 1 to 80% by weight of a polyalkylene glycol dialkyl ether of the following general formula (3) as an oligomer or a polymer to improve lithium salt dissociation and lithium ion conductivity:

Wherein R ₁ and R ₂ are C ₁ -C ₁₀ chained or branched alkyl groups, X, Y and Z are H or methyl groups, and p and q and r are each an integer from 0 to 20;

(4) 3 to 30% by weight of a lithium salt; And

(5) 0.001 to 1% by weight of a hardening platinum catalyst.

The electrolyte composition is used to prepare an electrolyte thin film by thermosetting.

A three-dimensionally crosslinked polymer is obtained by thermosetting a mixture of the compound of formula (1), the compound of formula (2) and a small amount of platinum catalyst. The crosslinked polymer can be molded into a thin film, and can increase the compatibility with a low molecular weight polyalkylene oxide and a lithium salt represented by Chemical Formula (3) to prepare an electrolyte thin film having excellent conductivity.

The compound of formula (1) used in the present invention can be synthesized by reacting polymethylsiloxane of formula (4) with allylalkylene oxide of formula (4) by a known method under a platinum catalyst, as shown in the following scheme (1). :

Wherein R ₁ and R ₂ are H or a methyl group; X is or Group; x and y are integers from 0 to 20; p and q are the integers of 0-1000, respectively.

The compound of formula (1) is mixed in an amount of 10 to 80% by weight, preferably 20 to 50% by weight, based on the total weight of the solid polymer electrolyte composition. If the content is less than 10% by weight or more than 80% by weight it is difficult to form a thin film and the mechanical properties of the film is lowered.

The polymer thus prepared is a viscous liquid and can be mixed with other components without phase separation, and does not require a separate solvent.

The crosslinking agent of formula (2) used in the present invention improves mechanical properties and ionic conductivity by forming a three-dimensional network structure by reacting with the compound of formula (1) under a platinum catalyst. Crosslinkers of formula (2) can be synthesized using commercially available compounds or from known techniques and the preparation methods are described in the Examples. The crosslinking agent of the formula (2) is mixed in the electrolyte composition at 1 to 60% by weight, preferably 5 to 30% by weight relative to the total weight of the solid polymer electrolyte. If the content is less than 1% by weight or more than 60% by weight, it is difficult to form a thin film and the mechanical properties of the film are lowered.

In the present invention, in order to improve lithium salt dissociation and lithium ion conductivity, polyalkylene glycol dialkyl ether of the above formula (3) is used as an oligomer or polymer. Examples of the compound of formula (3) which can be used in the present invention include polyethylene glycol dimethyl ether, polyethylene glycol diethyl ether, polyethylene glycol dipropyl ether, polyethylene glycol dibutyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol dimethyl ether And polypropylene glycol diglycidyl ether; Polypropylene glycol / polyethylene glycol copolymer of dibutyl ether terminal; Polyethylene glycol / polypropylene glycol / polyethylene glycol block copolymers at the end of the dibutyl ether. The polyalkylene glycol dialkyl ether of the formula (3) is used in an amount of 80% by weight or less, preferably 30 to 70% by weight in the composition for the purpose of imparting ionic conductivity to the solid polymer electrolyte to be produced. If the content is less than 30% by weight, there is a disadvantage that the conductivity is greatly reduced, if it exceeds 70% by weight it is difficult to form a thin film.

Lithium salt components used in the present invention are LiClO ₄ , LiCF ₃ SO ₃ , LiBF ₄ , LiPF ₆ , LiAsF ₆ , Li (CF ₃ SO ₂ ) ₂ N and the like, the lithium salt used for the production of conventional polymer electrolyte Any can be used. These lithium salts are used in an amount of 3 to 30% by weight, preferably 5 to 15% by weight based on the total weight of the electrolyte composition, and if necessary, the amount can be adjusted at an appropriate mixing ratio. If the content is less than 3% or more than 30% by weight, the ionic conductivity decreases.

In the present invention, a hardening platinum catalyst is added to prepare a solid polymer electrolyte, and examples thereof include H ₂ PtCl ₆ , platinum (0) -1,3-divinyl-1,1,3,3-tetramethyldisiloxane, Platinum activated carbon and the like, and 0.001% to 1% by weight is added to the electrolyte composition. If the content is less than 0.001% by weight, the curing speed decreases and the process time is long. If the content exceeds 1% by weight, the curing reaction occurs rapidly, making it difficult to produce a uniform thin film.

Referring to the method for producing a solid polymer electrolyte thin film with a composition comprising each of the above components, first, the siloxane polymer of formula (1), the crosslinking agent of formula (2) and lithium salt are put in a container at the ratio specified above The solution is prepared by stirring with a stirrer and then platinum catalyst is added and then mixed with each other. At this time, a low molecular weight polyalkylene oxide compound of formula (3) may be optionally added. The prepared solution is coated on a support such as a glass plate, a Teflon plate or a commercial Mylar film to an appropriate thickness, and cured for 5 minutes to 15 hours using a 30 to 150 ^° C. oven or a corresponding heat source. Prepare an electrolyte thin film.

A solid electrolyte thin film is prepared using the polysiloxane electrolyte composition according to the present invention, and an electrolyte lithium-polymer secondary battery is prepared using the thin film.

The solid polymer electrolyte composition prepared in the present invention may constitute a conventional lithium polymer secondary battery. The lithium polymer secondary battery may be configured by manufacturing the positive electrode with a lithium metal oxide / conductive material / binder and using the negative electrode with a carbon active material / conductive material / binder, lithium metal, or lithium metal alloy. Herein, the lithium metal oxide includes lithium manganese oxide, lithium nickel oxide, lithium cobalt oxide, lithium vanadium oxide, a complex metal oxide thereof, a metal oxide substituted with a part of transition metal, and oxygen or fluorine in the active material substituted with a compound such as sulfur. Forms of compounds are included. The carbon active materials include amorphous carbons such as coke-based, graphite-based such as natural graphite, fine fibrous or bead-like mesocarbons, tin-based compounds, and compounds treated with these.

All the above manufacturing processes are carried out in an argon atmosphere at room temperature.

As described above, the present invention uses a polyhydromethylsiloxane substituted with a polyalkylene oxide of the formula (1), a crosslinking agent of the formula (2) and a composition containing a low molecular weight polyalkylene oxide system, Physical properties such as strength and ionic conductivity are reinforced to provide a solid polymer electrolyte suitable for use in a lithium polymer secondary battery.

Hereinafter, the present invention will be described in more detail, but the present invention is not limited to the following examples as long as the present invention does not depart from the claims.

Example 1 Synthesis of Poly (ethyleneglycol) methylallylether (PEGM350Ae)

In a 1000 ml three-necked flask equipped with a stirrer, thermometer and dropping device, 6 g of NaOH and 35 g of poly (ethylene glycol) monomethyl ether (PEGME, molecular weight 350) were placed in THF (550 ml) dried with Na, under a nitrogen atmosphere. Excess allylbromide 18.15 g was added dropwise under reflux and refluxed for 12 hours. After the reaction was completed, the excess NaOH and NaBr produced was filtered, THF was removed under reduced pressure, extracted three times with a mixed solution of chloroform or methylene chloride and 5% (weight ratio) NaOH aqueous solution, dried over MgSO ₄ and dried in vacuo. 36.6 g of poly (ethylene glycol) methyl allyl ether (PEGM350Ae) was synthesized.

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 5.95 to 6.15 (m, CH ₂ = CH, 2H), 5.25 to 5.50 (m, CH ₂ = CH, 1H), 4.14 to 4.18 (m, CH ₂ = CHCH ₂ , 2H), 3.66-3.86 (m, OCH ₂ CH ₂ O, 28.8H), 3.52 (S, OCH ₃ , 3H)

Example 2 Synthesis of Poly (ethyleneglycol) methyletherallylcarbonate (PEGM350AC)

Synthesis of Poly (ethyleneglycol) methylethercarbonylimidazole (PEGMCI)

In a 1000 ml three-necked flask equipped with a stirring device, a thermometer and a dropping device, THF (200 ml) dried with Na was 35 g of poly (ethylene glycol) methyl ether (PEGME, molecular weight 350) and 19.45 g of 1,1-carbo Nyldiimidazole is added, and stirring is continued for 5 to 6 hours, maintaining 40-50 degreeC in nitrogen atmosphere. After the reaction was completed, the excess 1,1-carbonyldiimidazole was filtered, extracted three times with chloroform or methylene chloride and 5% (by weight) aqueous NaOH solution, dried over MgSO _4, and dried in vacuo to give 35.0 g of PEGMCI was prepared (yield 78.6%).

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 8.14 (s, NCHNCO, 1H), 7.44 (s, NCHCHNCO, 1H), 7.07 (s, NCHCHNCO, 1H), 3.66-3.86 (m, OCH ₂ CH ₂ O , 28.8H), 3.52 (S, OCH ₃ , 3H)

Synthesis of Poly (ethyleneglycol) methyletherallylcarbonate (PEGM350AC)

To a 1000 ml three-necked flask equipped with a stirrer, thermometer and dropping device, 35 g PEGMCI and 7.83 g allyl alcohol were added to THF (150 ml) dried with Na and stirring was continued for 24 hours under reflux under a nitrogen atmosphere. After the reaction, THF was evaporated, extracted three times with chloroform or methylene chloride and a 5% NaOH aqueous solution by weight, dried over MgSO _4, and dried in vacuo to prepare PEGM350AC containing 29.2 g of allylcarbonate (yield 85.4%). .

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 5.99-5.89 (m, CH ₂ = CH, 1H), 5.39-5.24 (m, CH ₂ = CH, 2H), 4.63-4.61 (d, CH ₂ = CHCH ₂ , 2H), 3.66-3.86 (m, OCH ₂ CH ₂ O, 28.8H), 3.52 (S, OCH ₃ , 3H)

Example 3 Synthesis of PEG Substituted Polyhydromethylsiloxane (PMS-A60)

Platinum (0) as a catalyst in a mixed solution of toluene (20 ml) dried with 2 g of polyhydromethylsiloxane (molecular weight 3000) and Na at room temperature under nitrogen atmosphere in a 1000 ml three-necked flask equipped with a stirring device, a thermometer and a dropping device. 6-10 μl of -1,3-divinyl-1,1,3,3-tetramethyldisiloxane (3% xylene solution by weight) is added and stirred for about 30 minutes to evenly distribute the Pt catalyst in the solution. After the temperature was raised to 40-50 ° C., 10.4 g of PEGM350Ae synthesized in Example 1 was slowly added dropwise. After the dropwise addition, stirring was continued for 4 hours, and another drop of Pt catalyst was added, followed by stirring for 1 hour. After the reaction was completed, toluene was volatilized and redissolved in diethyl ether, and the mixture was left at -5 ° C for 24 hours, the precipitate was removed, the dissolved content at -20 ° C was removed, and activated carbon was added and stirring was continued at room temperature for 24 hours. . The added activated carbon was filtered, and the solvent was evaporated, followed by vacuum drying for 24 hours under reduced pressure to obtain 10.4 g of colorless polyhydromethylsiloxane (PMS-A60) substituted with PEG. The PMS-A60 obtained at this time was analyzed by NMR and found that 60 mol% of the hydro group was substituted with the polyethylene oxide group.

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 4.60 (s, SiH), 3.54-3.57 (m, OCH ₂ CH ₂ O), 3.29 (s, OCH ₃ ), 1.52 (s, SiCH ₂ CH ₂ CH ₂ O), 0.41 (s, SiCH ₂ CH ₂ CH ₂ O), 0.00-0.09 (m, SiCH ₃ )

Example 4 Synthesis of PEG Substituted Polyhydromethylsiloxane (PMS-A80)

Using 2 g of polyhydromethylsiloxane (molecular weight 3000) and 13.85 g of PEGM350Ae, PMS-A80 having 80 mol% of a hydro group substituted with a polyethylene oxide group was synthesized in the same manner as in Example 3.

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 4.60 (s, SiH), 3.54-3.57 (m, OCH ₂ CH ₂ O), 3.29 (s, OCH ₃ ), 1.52 (s, SiCH ₂ CH ₂ CH ₂ O), 0.41 (s, SiCH ₂ CH ₂ CH ₂ O), 0.00-0.09 (m, SiCH ₃ )

Example 5 Synthesis of PEG Substituted Polyhydromethylsiloxane (PMS-AC60)

Using 2 g of polyhydromethylsiloxane (molecular weight 3000) and 16.6 g of PEGM350AC synthesized in Example 2, PMS-AC80 having 60 mol% of a hydro group substituted with a polyethylene oxide group was synthesized in the same manner as in Example 3.

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 4.60 (s, SiH), 3.54-3.57 (m, OCH ₂ CH ₂ O), 3.29 (s, OCH ₃ ), 1.52 (s, SiCH ₂ CH ₂ CH ₂ O), 0.41 (s, SiCH ₂ CH ₂ CH ₂ O), 0.00-0.09 (m, SiCH ₃ )

Example 6 Synthesis of Glycerol (ethoxylate-propoxylate) triallyl ether (GEPTA) as a crosslinking agent

To a 1000 ml three-necked flask equipped with a stirrer, thermometer and dropping device, 26 g of glycerol ethoxylate-propoxylatetriol (GEPTO, molecular weight 2600) and 1.8 g of NaOH were added to THF (200 ml) dried with Na. 5.45 g of allyl bromide was slowly added dropwise under reflux under a nitrogen atmosphere, and the reaction was continued for 10 hours under the same conditions. After the reaction was completed, the excess NaOH and the resulting NaBr was filtered, THF was evaporated, extracted three times with chloroform or methylene chloride and 5% aqueous NaOH solution, dried over MgSO ₄ and dried in vacuo to remove 25.1 g of allyl. GEPTA was prepared.

1 H-NMR (300 MHz, CDCl ₃ ): ppm 5.98-5.84 (m, CH ₂ = CH, 3H), 5.31-5.15 (m, CH ₂ = CH, 6H), 4.03-3.98 (d, CH ₂ = CHCH ₂ , 6H), 3.75-3.51 (m, OCH ₂ CH ₂ O, OCH ₂ CH ₂ CH ₂ O, OCH ₂ CHOCH ₂ O, 139H), 1.18-1.13 (m, OCH ₂ CH ₂ CH ₂ O, 40H)

Example 7 Preparation of Electrolyte Thin Film

0.2 g of PMS-A60 synthesized in Example 3, 0.21 g of GEPTA prepared in Example 6, 0.5 g of polyethylene glycol dimethyl ether (PEGDME, molecular weight 400) and 0.138 g of LiCF ₃ SO _{3 were} added and dissolved well. 6-10 μl of platinum (0) -1,3-divinyl-1,1,3,3-tetramethyldisiloxane (3% by weight xylene solution) by weight of the carstedts catalyst is mixed. After removing the bubbles contained in the sample under reduced pressure, the mixture was cured at room temperature for 2 hours and then cured at 60 ° C for 10 hours. All of the above-mentioned polymer solid electrolytes were prepared under argon atmosphere. Infrared spectroscopy spectra of PMS-A60 and the electrolyte prepared by the above method are shown in FIG. 1. After curing, it was found that the specific peak of Si-H bond of 2128 cm ^-1 disappeared completely.

Ion conductivity experiment

Ionic conductivity is obtained by coating a polymer thin film composition on a band-shaped conductive glass substrate or lithium-copper foil, then thermally curing to polymerize, drying sufficiently, and then measuring the AC impedance between the band-type or sandwich-type electrodes in a nitrogen atmosphere. , The measured values were analyzed by the frequency response analyzer to obtain the complex impedance analysis method. The band electrode was manufactured by attaching a masking tape having a width of 0.5 to 2 mm to the center of the conductive glass (ITO) at intervals of about 0.5 to 2 mm, placing it in an etching solution, etching, washing, and drying. The ion conductivity at room temperature of the polymer thin film solid electrolyte of Example 7 measured in this manner was 3.24 × 10 ⁻⁴ S / cm.

Examples 8-12 Preparation and Properties of Electrolyte Thin Films According to PEGDME Content

In the same manner as in Example 7, an electrolyte thin film was prepared while varying the content of PEGDME (molecular weight 400). At this time, the content of lithium salt was such that the molar ratio ([EO] / [Li]) of the ethylene oxide repeater and the lithium salt was 15. The conductivity and glass transition temperature of the prepared thin film are shown in Table 1.

Conductivity and glass transition temperature depending on PEGDME (molecular weight 400) content Example PMS-A60 GEPTA PEGDME (molecular weight 400) LiCF ₃ SO ₃ Platinum Catalyst Room temperature ion conductivity (× 10 ⁵ S / cm) Glass transition temperature (℃) 8 0.2 g 0.21 g - 0.0547 g 6 to 10 µl 2.35 -56.25 9 0.2 g 0.21 g 0.2 g 0.0756 g 6 to 10 µl 8.10 -59.52 10 0.2 g 0.21 g 0.3 g 0.0964g 6 to 10 µl 16.1 -67.89 11 0.2 g 0.21 g 0.4g 0.1173 g 6 to 10 µl 27.9 -69.72 12 0.2 g 0.21 g 0.6g 0.1801 g 6 to 10 µl 56.0 -73.74

Examples 13-15 Preparation and Properties of Electrolyte Thin Films According to PEGDME Molecular Weight

The electrolyte thin film was prepared in the same manner as in Example 7, varying the molecular weight of PEGDME. At this time, the content of lithium salt was such that the molar ratio ([EO] / [Li]) of the ethylene oxide repeater and the lithium salt was 15. The conductivity and glass transition temperature of the prepared thin film are shown in Table 2.

Conductivity and glass transition temperature depending on PEGDME molecular weight Example PMS-A60 GEPTA PEGDME LiCF ₃ SO ₃ Platinum Catalyst Room temperature ion conductivity (× 10 ⁵ S / cm) Glass transition temperature (℃) Molecular Weight usage 13 0.2 g 0.21 g 178.23 0.2 g 0.0547 g 6 to 10 µl 2.35 -55.40 14 0.2 g 0.21 g 250 0.2 g 0.0756 g 6 to 10 µl 8.10 -78.47 15 0.2 g 0.21 g 500 0.2 g 0.1173 g 6 to 10 µl 27.9 -64.29

Examples 16-19 Preparation and Properties of Electrolyte Thin Films According to Lithium Salt Concentration

The electrolyte thin film was prepared in the same manner as in Example 7, varying the molecular weight of PEGDME. At this time, the content of lithium salt was such that the molar ratio ([EO] / [Li]) of the ethylene oxide repeater and the lithium salt was 15. The conductivity and glass transition temperature of the prepared thin film are shown in Table 3.

Conductivity and Glass Transition Temperature with Lithium Salt Concentration Example PMS-A60 GEPTA PEGDMe (molecular weight 400) LiCF ₃ SO ₃ Platinum Catalyst Room temperature ion conductivity (× 10 ⁵ S / cm) Glass transition temperature (℃) 16 0.2 g 0.21 g 0.2 g 0.1446 g 6 to 10 µl 34.7 -63.40 17 0.2 g 0.21 g 0.2 g 0.0723 g 6 to 10 µl 50.8 -71.66 18 0.2 g 0.21 g 0.2 g 0.0482 g 6 to 10 µl 29.4 -65.70 19 0.2 g 0.21 g 0.2 g 0.03615 g 6 to 10 µl 25.5 -64.74

Examples 20-23 Curing Agent Synthesis

Example 20 Synthesis of Glycerol Ethoxylate Triallyl Ether (GETA)

To a 1000 ml three-necked flask equipped with a stirrer, thermometer, and dropping device, 10 g of glycerol ethoxylate triol (GETO, molecular weight 1000) and 1.8 g of NaOH were added to THF (150 ml) dried with Na and under a nitrogen atmosphere. 5.45 g of allyl bromide was slowly added dropwise under reflux, and 9.48 g (yield 84.7%) of GETA was prepared in the same manner as in Example 6.

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 5.96-5.84 (m, CH ₂ = CH, 3H), 5.31-5.15 (m, CH ₂ = CH, 6H), 4.04-4.01 (d, CH ₂ = CHCH ₂ , 6H), 3.82-3.59 (m, OCH ₂ CH ₂ O, OCH ₂ CHOCH ₂ O, 84H)

Example 21 Synthesis of Glycerol (ethoxylate-propoxylate) triallylcarbonate (GEPTAC)

Synthesis of Glycerol (ethoxylate-propoxylate) tricarbonylimidazole (GEPTCI)

To a 1000 ml three-necked flask equipped with a stirrer, thermometer, and dropping device, 26 g of GEPTO (molecular weight 2600) and 8.11 g of 1,1-carbonyldiimidazole were added to THF (200 ml) dried with Na and a nitrogen atmosphere. The stirring is continued for 5 to 6 hours while maintaining the temperature at 40 to 50 ° C. After the reaction was completed, the excess 1,1-carbonyldiimidazole was filtered, extracted three times with chloroform or methylene chloride and 5% NaOH aqueous solution by weight, dried over MgSO _4, and dried in vacuo to give 26.19 g of GEPTCI. Prepared (yield 90.8%).

1 H-NMR (300 MHz, CDCl 3): ppm 8.14 (s, NCHNCO, 3H), 7.44 (s, NCHCHNCO, 3H), 7.07 (s, NCHCHNCO, 3H), 3.91-3.30 (m, OCH ₂ CH ₂ O, OCH ₂ CH ₂ CH ₂ O, OCH ₂ CHOCH ₂ O, 139H), 1.42-1.39 (m, OCOCH ₂ CH ₂ CH ₂ O, 6H), 1.19-1.13 (m, OCOCH ₂ CH ₂ CH ₂ O, 34H)

Synthesis of Glycerol (ethoxylate-propoxylate) triallylcarbonate (GEPTAC)

To a 1000 ml three-necked flask equipped with a stirrer, thermometer and dropping device, THF (150 ml) dried with Na was added 26.1 g of GEPTCI and 3.16 g of allyl alcohol and stirring was continued for 24 hours under reflux under a nitrogen atmosphere. After the reaction, THF was evaporated, extracted three times with chloroform or methylene chloride and 5% NaOH aqueous solution by weight, dried over MgSO _4, and dried in vacuo to prepare GEPTAC containing 22.05 g of allylcarbonate (yield 82.4%). ).

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 5.99-5.89 (m, CH ₂ = CH, 3H), 5.39-5.24 (m, CH ₂ = CH, 6H), 4.63-4.61 (d, CH ₂ = CHCH ₂ , 6H), 3.65-3.38 (m, OCH ₂ CH ₂ O, OCH ₂ CH ₂ CH ₂ O, OCH ₂ CHOCH ₂ O, 139H), 1.28-1.31 (m, OCOCH ₂ CH ₂ CH ₂ O, 6H) , 1.19-1.13 (m, OCOCH ₂ CH ₂ CH ₂ O, 34H)

Example 22 Synthesis of Glycerol Ethoxylate Triallylcarbonate (GETAC)

Synthesis of Glycerol Ethoxylate Tridiimidazole (GETCI)

10 g of GETO (molecular weight 1000) and 8.11 g of 1.1-carbonyldiimidazole are added and stirring is continued for 5 to 6 hours while maintaining 40 to 50 ° C. under a nitrogen atmosphere. After the reaction was completed, the excess 1,1-carbonyldiimidazole was filtered, extracted three times with chloroform or methylene chloride, dried over MgSO ₄ and dried in vacuo to prepare 11.4 g of GETCI (yield 88.7% ).

¹ H-NMR (300 MHz, CDCl ₃ ): ppm 8.14 (s, NCHNCO, 3H), 7.44 (s, NCHCHNCO, 3H), 7.07 (s, NCHCHNCO, 3H), 3.75-3.51 (m, OCH ₂ CH ₂ O , OCH ₂ CHOCH ₂ O, 84H)

Synthesis of Glycerol Ethoxylate Triallylcarbonate (GETAC)

To a 1000 ml three-necked flask equipped with a stirrer, thermometer and dropping device, 11.4 g of GETCI and 3.09 g of allyl alcohol were added to THF (200 ml) dried with Na and stirring was continued for 24 hours under reflux under a nitrogen atmosphere. After the reaction, THF was evaporated, extracted three times with chloroform or methylene chloride and 5% NaOH aqueous solution by weight, dried over MgSO _4, and dried in vacuo to prepare 7.57 g of allylcarbonate-containing GETAC (yield 76.2%). ).

¹ H-NMR (300 MHz, CDCl ³ ): ppm 5.95-5.88 (m, CH ₂ = CH, 3H), 5.39-5.24 (m, CH ₂ = CH, 6H), 4.64-4.61 (d, CH ₂ = CHCH ₂ , 6H), 75-3.51 (m, OCH ₂ CH ₂ O, OCH ₂ CHOCH ₂ O, 78.72H)

Examples 23 to 27 Preparation and Properties of Electrolyte Thin Films according to Curing Agents

Using the PMS-A60 synthesized in Example 3 and using a curing agent as shown in Table 4 to prepare an electrolyte thin film in the same manner as in Example 7. The curing agents used at this time were 2,4,6-triallyloxy-1,3,5-triazine (TAOTA) and triallyl-1,3-5-triazine, which are commercially available reagents synthesized in Examples 20-22. -2,4,6-trione (TATT) was used, and the lithium salt content was such that the molar ratio ([EO] / [Li]) of the ethylene oxide repeater and the lithium salt was 15. The conductivity and glass transition temperature of the prepared thin film are shown in Table 4.

Conductivity and glass transition temperature depending on the hardener Example PMS-A60 Hardener PEGDME (molecular weight 400) LiCF ₃ SO ₃ Platinum Catalyst Room temperature ion conductivity (× 10⁵S / cm) Glass transition temperature (℃) Kinds usage 23 0.2 g GETA 0.086 g 0.2 g 0.0756 g 6 to 10 µl 20.5 -66.93 24 0.2 g GEPTAC 0.218 g 0.2 g 0.0964g 6 to 10 µl 31.1 - 25 0.2 g GETAC 0.096 g 0.2 g 0.1173 g 6 to 10 µl 25.7 -59.52 26 0.2 g TAOTA 0.019 g 0.2 g 0.0697 g 6 to 10 µl 22.7 - 27 0.2 g TATT 0.019 g 0.2 g 0.0697 g 6 to 10 µl 26.0 -

Examples 28-29 Preparation and Properties of Electrolyte Thin Films Using PMS-AC60

An electrolyte thin film was prepared in the same manner as in Example 7, using PMS-AC60 synthesized in Example 5 and using GEPTAC and GETAC as curing agents. At this time, the content of the lithium salt used was such that the molar ratio ([EO] / [Li]) of the ethylene oxide repeater and the lithium salt was 15. The conductivity and glass transition temperature of the prepared thin film are shown in Table 5.

Conductivity and Glass Transition Temperature of Electrolytic Thin Films Using PMS-AC60 Example PMS-AC60 Hardener PEGDME (molecular weight 400) LiCF ₃ SO ₃ Platinum Catalyst Room temperature ion conductivity (× 10^-5S / cm) Glass transition temperature (℃) Kinds usage 28 0.2 g GEPTAC 0.218 g 0.2 g 0.0964g 6 to 10 µl 34.1 -64.96 29 0.2 g GETAC 0.096 g 0.2 g 0.1173 g 6 to 10 µl 28.7 -62.69

Example 30 Electrochemical Stability Experiment

An electrolytic thin film was directly prepared on a 1 cm × 1 cm stainless electrode in the same manner as in Example 12, sandwiched between lithium metals, and vacuum packed to prepare a cell for measuring electrochemical stability. Electrochemical stability was measured at a rate of 1 mV / sec from 2.0 to 5.0 V using the linear scanning potential method. This result is shown in FIG. As a result of the measurement, there was almost no current to decompose the electrolyte below 4.75V. The polymer electrolyte prepared therefrom was electrochemically stable up to 4.75V at the lithium reference electrode, and it was confirmed that the polymer electrolyte had sufficient electrochemical stability as a polymer electrolyte for lithium-polymer batteries.

The solid polymer electrolyte thin film according to the present invention has enhanced mechanical properties such as thin film formability and compressive strength, and is easy to introduce low molecular weight polyalkylene oxide, thereby improving ion conductivity at room temperature, and excellent adhesion to electrodes. And, it can be chemically and electrochemically stable to provide a solid polymer electrolyte thin film suitable for use in a lithium-polymer secondary battery.

Claims (5)

Regarding the total weight of the solid polymer electrolyte composition, (1) 10 to 80% by weight of polyhydromethylsiloxane in which the polyalkylene oxide group represented by the following general formula (1) is introduced side by side: Wherein R ₁ and R ₂ are H or a methyl group, X is or X and y are each an integer of 0 to 20, and p and q are each an integer of 0 to 1000; (2) 1 to 60 wt% of a crosslinking agent having three allyl groups at the terminal represented by the following general formula (2): Wherein R is a C ₁ -C ₁₀ linear or cyclic aliphatic and aromatic compound or a heterocyclic compound represented by triazine, isocyanurate or the like, X is or And x, y and z are integers from 0 to 20; (3) Polyalkylene glycol dialkyl ethers represented by the following general formula (3) as oligomers or polymers for improving lithium salt dissociation and lithium ion conductivity: Wherein R ₁ and R ₂ are C ₁ -C ₁₀ chained or branched alkyl groups, X, Y and Z are H or methyl groups, and p, q and r are each a number from 0 to 20; (4) 3 to 30% by weight of a lithium salt; And (5) 0.001 to 1% by weight of a hardening platinum catalyst Polysiloxane electrolyte composition comprising a. The method of claim 1, wherein the polyalkylene glycol dialkyl ether is polyethylene glycol dimethyl ether, polyethylene glycol diethyl ether, polyethylene glycol dipropyl ether, polyethylene glycol dibutyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol dimethyl ether And polypropylene glycol diglycidyl ether; Polypropylene glycol / polyethylene glycol copolymer of dibutyl ether terminal; Polysiloxane electrolyte composition which is a polyethyleneglycol / polypropylene glycol / polyethyleneglycol block copolymer of a dibutyl ether terminal. The polysiloxane electrolyte composition of claim 1, wherein the lithium salt is LiClO ₄ , LiCF ₃ SO ₃ , LiBF ₄ , LiPF ₆ , LiAsF _6, or Li (CF ₃ SO ₂ ) ₂ N. 7. The polyhydromethylsiloxane of the formula (1), the crosslinking agent of the formula (2) and the lithium salt were added to a container, and the platinum catalyst was added to the solution obtained by stirring with a stirrer and mixed, and then the low molecular weight polyalkylene jade of the formula (3) The solution obtained by selectively adding a seed compound is coated on a support such as a glass plate, a Teflon plate or a commercial Mylar film, and then cured and reacted at 30 to 150 ^° C. for 5 minutes to 15 hours to form a polysiloxane solid electrolyte thin film. How to prepare. The polysiloxane solid electrolyte thin film prepared by claim 4.