WO2015030137A1

WO2015030137A1 - Resin composition for gasket, production method therefor, and gasket for secondary battery

Info

Publication number: WO2015030137A1
Application number: PCT/JP2014/072635
Authority: WO
Inventors: 芳野　泰之; 渡辺　創; 俊男檜森
Original assignee: Dic株式会社
Priority date: 2013-08-30
Filing date: 2014-08-28
Publication date: 2015-03-05
Also published as: KR102595639B1; CN105493310B; JPWO2015030137A1; CN105493310A; KR20220002719A; JP6233415B2; KR20160049537A

Abstract

Provided are: a resin composition for a gasket, said resin composition being used as a material for a gasket used in a sealed secondary battery (storage battery) such as a lithium ion secondary battery, and exhibiting excellent cavity balance and a high mechanical strength; a production method for said resin composition; and a gasket for a secondary battery. More specifically, the present invention relates to: a resin composition for a gasket used in a secondary battery configured from a positive electrode, a negative electrode, a sealing body, a gasket, a separator, and an electrolyte, said resin composition including a polyarylene sulfide resin and a silicone compound, and being capable of being obtained using a method including a step in which the polyarylene sulfide resin is subjected to a reaction in a molten mixture including a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor; a production method for said resin composition; and a gasket for a secondary battery.

Description

Resin composition for gasket, method for producing the same, and gasket for secondary battery

The present invention relates to a gasket resin composition used for a secondary battery gasket, a method for producing the same, and a secondary battery gasket.

A sealed secondary battery generally includes a positive electrode plate, a negative electrode plate, an electrode plate group including a separator disposed between the positive electrode plate and the negative electrode plate, and a battery element including an electrolytic solution for immersing the electrode plate group. Is housed inside a partially opened battery case (exterior body), and is sealed by a sealing body for sealing the opening of the battery case. Further, in this sealed secondary battery, for example, a contact point between the positive electrode terminal electrically connected to the positive electrode plate and a contact point between the negative electrode terminal electrically connected to the negative electrode plate are between a pair of terminals. Gaskets are provided to prevent short circuits and electrolyte leakage. The gasket is required to have resistance to electrolyte and excellent airtightness against the electrolyte.

In order to satisfy these requirements, for example, a technique using a polyamide resin having improved heat and humidity resistance as a gasket material has been reported (for example, see Patent Document 1). However, although the heat and moisture resistance can be slightly improved by using a polyamide resin having improved moisture and heat resistance, the degree of resistance to electrolyte and airtightness is still insufficient.

On the other hand, it has been reported that a gasket using a polyarylene sulfide resin or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin as a gasket material has excellent airtightness and electrolyte resistance (for example, Patent Documents). 2).

JP 2005-78890 A JP-A-8-32287

In recent years, the use of an active material with a high theoretical capacity as an electrode material has led to an increase in the capacity of lithium ion batteries, but on the other hand, the volume of the internal medium has increased significantly by 3 to 4 times during charging and discharging, and the pressure of the internal medium has been dramatically increased. It is getting higher. In addition, as a result of the increased specific gravity of in-vehicle applications such as hybrid vehicles (HV) and electric vehicles (EV), higher safety is required, and the reliability of the gasket's airtightness under severe conditions of high temperature and high humidity. Is becoming necessary at an extremely high level.

However, the conventional gasket material does not endure the pressure of the internal medium, and does not reach the level required for a sealed secondary battery (storage battery) such as a lithium ion secondary battery that has been demanded in recent years. Is insufficient. Therefore, the gasket material is required to improve the mechanical strength.

On the other hand, when a plurality of gaskets are molded at the same time by injection molding using a mold having a plurality of cavities, a molding defect such that a part of the cavities is not sufficiently filled with molding material may occur. . Therefore, the molding material is also required to be able to be filled evenly and uniformly.

Accordingly, the main problem to be solved by the present invention is a gasket having excellent cavity balance and high mechanical strength as a gasket material used in a sealed secondary battery (storage battery) such as a lithium ion secondary battery. It is providing the resin composition for batteries, its manufacturing method, and the gasket for secondary batteries.

As a result of various studies, the present inventors use a resin composition containing a polyarylene sulfide resin obtained by melt polymerization of a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor, and a silicone compound. As a result, the inventors have found that the above problems can be solved, and have completed the present invention. The present invention has been completed.

That is, the present invention is a resin composition for a gasket used for a secondary battery composed of a positive electrode, a negative electrode, a sealing body, a gasket, a separator, and an electrolyte solution, comprising a polyarylene sulfide resin and a silicone compound, The arylene sulfide resin can be obtained by a method comprising reacting a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor in a molten mixture containing the diiodo aromatic compound, elemental sulfur and the polymerization inhibitor. There is provided a resin composition for a gasket. The present invention also provides a secondary battery gasket comprising the above gasket resin composition.

The present invention further relates to a method for producing a resin composition for a gasket used in a secondary battery composed of a positive electrode, a negative electrode, a sealing body, a gasket, a separator, and an electrolyte solution, wherein the polyarylene sulfide resin and the silicone compound are mixed. A polyarylene sulfide resin comprising reacting a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor in a molten mixture containing the diiodo aromatic compound, elemental sulfur and the polymerization inhibitor. A method for producing a resin composition for a gasket, which can be obtained by the method.

According to the present invention, as a gasket material used in a sealed secondary battery (storage battery) such as a lithium ion secondary battery, a resin composition for gasket having excellent cavity balance and high mechanical strength, and a method for producing the same And a gasket for a secondary battery. Moreover, the gasket for secondary batteries which suppressed the gas generation by a heating can be produced by using the said resin composition for gaskets.

It is a schematic diagram which shows the test piece used for the compression stress relaxation test.

Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

The resin composition for a gasket according to the present embodiment contains a polyarylene sulfide resin and a silicone compound.

The polyarylene sulfide resin used in the present embodiment is obtained by reacting a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor in a molten mixture containing the diiodo aromatic compound, elemental sulfur and the polymerization inhibitor. It can be obtained by the method of including. According to such a method, a polyarylene sulfide resin can be obtained as a polymer having a relatively high molecular weight as compared with conventional methods such as the Philips method.

The diiodo aromatic compound has an aromatic ring and two iodine atoms directly bonded to the aromatic ring. Examples of diiodo aromatic compounds include, but are not limited to, diiodobenzene, diiodotoluene, diiodoxylene, diiodonaphthalene, diiodobiphenyl, diiodobenzophenone, diiododiphenyl ether, and diiododiphenyl sulfone. The substitution positions of the two iodine atoms are not particularly limited, but it is preferable that the two substitution positions are located as far as possible in the molecule. Preferred substitution positions are the para position and the 4,4'-position.

Aromatic rings of diiodo aromatic compounds include phenyl groups, halogen atoms other than iodine atoms, hydroxy groups, nitro groups, amino groups, alkoxy groups having 1 to 6 carbon atoms, carboxy groups, carboxylates, aryl sulfones and aryl ketones. It may be substituted with at least one substituent selected from However, from the viewpoint of crystallinity and heat resistance of the polyarylene sulfide resin, the ratio of the substituted diiodo aromatic compound to the unsubstituted diiodo aromatic compound is preferably in the range of 0.0001 to 5% by mass. More preferably, it is in the range of 0.001 to 1% by mass.

The elemental sulfur means a substance (S ₈ , S ₆ , S ₄ , S _2, etc.) composed only of sulfur atoms, and its form is not limited. More specifically, the present invention may be used elemental sulfur which is commercially available as Tsuboneho medicament may be obtained generically, may be used a mixture containing S ₈ and S ₆ and the like. The purity of elemental sulfur is not particularly limited. The elemental sulfur may be in the form of particles or powder as long as it is solid at room temperature (23 ° C.). The particle size of elemental sulfur is not particularly limited, but is preferably in the range of 0.001 to 10 mm, more preferably in the range of 0.01 to 5 mm, and still more preferably in the range of 0.01 to 3 mm.

The polymerization inhibitor can be used without particular limitation as long as it is a compound that inhibits or stops the polymerization reaction in the polymerization reaction of the polyarylene sulfide resin. The polymerization inhibitor preferably contains a compound capable of introducing at least one group selected from the group consisting of a hydroxy group, an amino group, a carboxyl group and a salt of a carboxyl group at the end of the main chain of the polyarylene sulfide resin. That is, the polymerization inhibitor is preferably a compound having one or more groups selected from the group consisting of a hydroxy group, an amino group, a carboxyl group, and a carboxyl group salt. Moreover, the polymerization inhibitor may have the functional group, or the functional group may be generated by a polymerization termination reaction or the like.

As the polymerization inhibitor having a hydroxy group or an amino group, for example, a compound represented by the following formula (1) or (2) can be used as the polymerization inhibitor.

According to the compound represented by the general formula (1), a monovalent group represented by the following formula (1-1) is introduced as a terminal group of the main chain. Y in the formula (1-1) is a hydroxy group, an amino group or the like derived from a polymerization inhibitor.

According to the compound represented by the general formula (2), a monovalent group represented by the following formula (2-1) is introduced as a terminal group of the main chain. A hydroxy group derived from the compound represented by the general formula (1) can be introduced into the polyarylene sulfide resin by, for example, bonding to a carbon atom of a carbonyl group in the formula (2) and a sulfur radical.

In the group represented by the formula (1-1) or (2-1), the disulfide bond that is derived from the raw material (single sulfur) in the main chain of the polyarylene sulfide resin is radically cleaved at the melting temperature. The generated sulfur radical and the compound represented by the general formula (1) or the compound represented by the general formula (2) are considered to be introduced into the polyarylene sulfide resin. The existence of these structural units having a specific structure is characteristic of the polyarylene sulfide resin obtained by melt polymerization using the compound represented by the general formula (1) or (2).

Examples of the compound represented by the general formula (1) include 2-iodophenol and 2-aminoaniline. Examples of the compound represented by the general formula (2) include 2-iodobenzophenone.

As the polymerization inhibitor having a carboxyl group, for example, one or more compounds selected from the compounds represented by the following general formula (3), (4) or (5) may be used.

In the general formula (3), R ¹ and R ² each independently represent a hydrogen atom or a monovalent group represented by the following general formula (a), (b) or (c), and R ¹ or At least one of R ² is a monovalent group represented by the general formula (a), (b) or (c). In General Formula (4), Z represents an iodine atom or a mercapto group, and R ³ represents a monovalent group represented by the following General Formula (a), (b), or (c). In the general formula (5), ^{R 4} is formula (a), represents a monovalent group represented by (b) or (c).

X in the general formulas (a) to (c) is a hydrogen atom or an alkali metal atom, and is preferably a hydrogen atom from the viewpoint of good reactivity. Examples of the alkali metal atom include sodium, lithium, potassium, rubidium, and cesium, and sodium is preferable. In the general formula (b), R ¹⁰ represents an alkyl group having 1 to 6 carbon atoms. In the general formula (c), R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹² represents an alkyl group having 1 to 5 carbon atoms.

According to the compound represented by the general formula (3), (4) or (5), a monovalent group represented by the following formula (6) or (7) is introduced as a terminal group of the main chain. The presence of the terminal structural unit of these specific structures is characteristic of the polyarylene sulfide resin obtained by melt polymerization using the compound represented by the general formula (3), (4) or (5).

(In the formula, R ⁵ represents a monovalent group represented by the general formula (a), (b) or (c)).

(In the formula, R ⁶ represents a monovalent group represented by the general formula (a), (b) or (c)).

As the polymerization inhibitor, a compound having no functional group such as a carboxyl group may be used. Examples of such compounds include diphenyl disulfide, monoiodobenzene, thiophenol, 2,2′-dibenzothiazolyl disulfide, 2-mercaptobenzothiazole, N-cyclohexyl-2-benzothiazolylsulfenamide, 2 At least one compound selected from-(morpholinothio) benzothiazole and N, N'-dicyclohexyl-1,3-benzothiazole-2-sulfenamide can be used.

The polyarylene sulfide resin according to this embodiment is obtained by performing melt polymerization in a melt mixture obtained by heating a mixture containing a diiodo aromatic compound, elemental sulfur, a polymerization inhibitor, and a catalyst as necessary. Generate. The ratio of the diiodo aromatic compound in the molten mixture is preferably in the range of 0.5 to 2 moles, more preferably in the range of 0.8 to 1.2 moles per mole of elemental sulfur. The ratio of the polymerization inhibitor in the mixture is preferably in the range of 0.0001 to 0.1 mol, more preferably in the range of 0.0005 to 0.05 mol, with respect to 1 mol of solid sulfur. .

The timing of adding the polymerization inhibitor is not particularly limited, but the temperature of the mixture is preferably 200 ° C. to 320 ° C. by heating the mixture containing the diiodo aromatic compound, elemental sulfur and the catalyst to be added as necessary. The polymerization inhibitor can be added when the temperature is within the range, more preferably within the range of 250 to 320 ° C.

The polymerization rate can be adjusted by adding a nitro compound as a catalyst to the molten mixture. As this nitro compound, various nitrobenzene derivatives can be usually used. Examples of the nitrobenzene derivative include 1,3-diiodo-4-nitrobenzene, 1-iodo-4-nitrobenzene, 2,6-diiodo-4-nitrophenol and 2,6-diiodo-4-nitroamine. The amount of the catalyst is usually an amount added as a catalyst, and is preferably in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of elemental sulfur, for example.

The conditions for melt polymerization are appropriately adjusted so that the polymerization reaction proceeds appropriately. The temperature of the melt polymerization is preferably 175 ° C. or higher, the melting point of the polyarylene sulfide resin to be formed + 100 ° C. or lower, more preferably 180 to 350 ° C. The melt polymerization is carried out with an absolute pressure of preferably 1 [cPa] to 100 [kPa], more preferably 13 [cPa] to 60 [kPa]. The conditions for melt polymerization need not be constant. For example, at the initial stage of polymerization, the temperature is preferably in the range of 175 to 270 ° C., more preferably in the range of 180 to 250 ° C., and the absolute pressure is in the range of 6.7 to 100 [kPa], and then continuously or Polymerization is carried out while raising and lowering the temperature stepwise, and in the latter stage of polymerization, the temperature is preferably 270 ° C. or higher, the melting point of the polyarylene sulfide resin to be produced + 100 ° C. or lower, more preferably 300 to 350 ° C., In addition, the polymerization can be carried out at an absolute pressure in the range of 1 [cPa] to 6 [kPa]. In the present specification, the melting point of the resin means a value measured in accordance with JIS K 7121 using a differential scanning calorimeter (Perkin Elmer DSC device Pyris Diamond).

The melt polymerization is preferably performed in a non-oxidizing atmosphere from the viewpoint of obtaining a high degree of polymerization while preventing oxidative crosslinking reaction. In the non-oxidizing atmosphere, the oxygen concentration in the gas phase is preferably in the range of less than 5% by volume, more preferably in the range of less than 2% by volume, and more preferably the gas phase is substantially free of oxygen. The non-oxidizing atmosphere is preferably an inert gas atmosphere such as nitrogen, helium and argon.

The melt polymerization can be performed using, for example, a melt kneader equipped with a heating device, a decompression device, and a stirring device. Examples of the melt kneader include a Banbury mixer, a kneader, a continuous kneader, a single screw extruder, and a twin screw extruder.

It is preferable that the molten mixture for melt polymerization does not substantially contain a solvent. More specifically, the amount of the solvent contained in the molten mixture is preferably 10 masses with respect to a total of 100 mass parts of the diiodo aromatic compound, elemental sulfur, the polymerization inhibitor, and, if necessary, the catalyst. Part or less, more preferably 5 parts by weight or less, and even more preferably 1 part by weight or less. The amount of the solvent may be 0 part by mass or more, 0.01 part by mass or more, or 0.1 part by mass or more.

After the melt mixture (reaction product) after the melt polymerization is cooled to obtain a solid state mixture, the mixture is heated under reduced pressure or atmospheric pressure in a non-oxidizing atmosphere to further advance the polymerization reaction. Also good. As a result, not only can the molecular weight be increased, but also the generated iodine molecules are sublimated and removed, so the iodine atom concentration in the polyarylene sulfide resin can be kept low. The solid state mixture can be obtained by cooling to a temperature of preferably 100 to 260 ° C, more preferably 130 to 250 ° C, and even more preferably 150 to 230 ° C. Heating after cooling to the solid state can be performed under the same temperature and pressure conditions as in melt polymerization.

The reaction product containing the polyarylene sulfide resin obtained by the melt polymerization step can be directly produced in a melt-kneader to produce a resin composition. It is preferable to prepare a dissolved product by adding a solvent in which the reaction product is dissolved, and to take out the reaction product from the reaction apparatus in the dissolved state because not only the productivity is improved but also the reactivity is improved. The addition of the solvent in which the reaction product is dissolved is preferably performed after the melt polymerization, but it may be performed in the later stage of the reaction of the melt polymerization, or as described above, the molten mixture (reaction product) is cooled to form a solid state. After obtaining the mixture, the polymerization reaction may be further advanced by heating the mixture under pressure, reduced pressure, or atmospheric pressure in a non-oxidizing atmosphere. The step of preparing the lysate may be performed in a non-oxidizing atmosphere. The temperature for dissolution by heating may be in the range of the melting point of the solvent in which the reaction product dissolves, preferably in the range of 200 to 350 ° C., more preferably in the range of 210 to 250 ° C. It is preferable to carry out with.

The mixing ratio of the solvent used for preparing the dissolved product in which the reaction product dissolves is preferably in the range of 90 to 1000 parts by mass with respect to 100 parts by mass of the reaction product containing polyarylene sulfide resin. The range is preferably 200 to 400 parts by mass.

As the solvent in which the reaction product is dissolved, for example, a solvent used as a polymerization reaction solvent in solution polymerization such as a Philips method can be used. Examples of preferable solvents include N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP), N-cyclohexyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, and ε-caprolactam. Aliphatic cyclic amide compounds such as N-methyl-ε-caprolactam, amide compounds such as hexamethylphosphoric triamide (HMPA), tetramethylurea (TMU), dimethylformamide (DMF), and dimethylacetamide (DMA), polyethylene Examples include etherified polyethylene glycol compounds such as glycol dialkyl ether (having a degree of polymerization of 2000 or less and an alkyl group having 1 to 20 carbon atoms), and sulfoxide compounds such as tetramethylene sulfoxide and dimethyl sulfoxide (DMSO). It is done. Examples of other usable solvents include benzophenone, diphenyl ether, diphenyl sulfide, 4,4′-dibromobiphenyl, 1-phenylnaphthalene, 2,5-diphenyl-1,3,4-oxadiazole, 2,5- Diphenyloxazole, triphenylmethanol, N, N-diphenylformamide, benzyl, anthracene, 4-benzoylbiphenyl, dibenzoylmethane, 2-biphenylcarboxylic acid, dibenzothiophene, pentachlorophenol, 1-benzyl-2-pyrrolidione, 9- Fluorenone, 2-benzoylnaphthalene, 1-bromonaphthalene, 1,3-diphenoxybenzene, fluorene, 1-phenyl-2-pyrrolidinone, 1-methoxynaphthalene, 1-ethoxynaphthalene, 1,3-diphenylacetate 1,4-dibenzoylbutane, phenanthrene, 4-benzoylbiphenyl, 1,1-diphenylacetone, o, o'-biphenol, 2,6-diphenylphenol, triphenylene, 2-phenylphenol, thianthrene, 3-phenoxy Benzyl alcohol, 4-phenylphenol, 9,10-dichloroanthracene, triphenylmethane, 4,4'-dimethoxybenzophenone, 9,10-diphenylanthracene, fluoranthene, diphenylphthalate, diphenyl carbonate, 2,6-dimethoxynaphthalene, 2,7-dimethoxynaphthalene, 4-bromodiphenyl ether, pyrene, 9,9'-bifluorene, 4,4'-isopropylidene-diphenol, epsilon-caprolactam, N-cyclohexyl 2-pyrrolidone, diphenyl isophthalate, one or more solvents thereof selected from diphenyl chromatography terpolymers phthalate and the group consisting of 1-chloronaphthalene.

The melted product taken out from the reaction apparatus is preferably post-treated and then melt-kneaded with the other components to prepare a resin composition because the reactivity becomes better. The method for post-treatment of the lysate is not particularly limited, and examples thereof include the following methods.
(1) The solvent is used as it is or after adding an acid or a base, and then the solvent is distilled off under reduced pressure or normal pressure. (Or an organic solvent having an equivalent solubility with respect to a low-molecular polymer), a method of washing once or twice or more with a solvent selected from acetone, methyl ethyl ketone and alcohols, and further neutralizing, washing with water, filtering and drying.
(2) Solvents such as water, acetone, methyl ethyl ketone, alcohol, ether, halogenated hydrocarbon, aromatic hydrocarbon and aliphatic hydrocarbon (soluble in the solvent of the solution and at least polyarylene) A solvent which is a poor solvent for sulfide resin) is added as a precipitating agent to precipitate a solid product containing polyarylene sulfide resin and inorganic salt, and the solid product is filtered, washed and dried. Method.
(3) After adding the solvent used for the dissolved material (or an organic solvent having an equivalent solubility with respect to the low molecular weight polymer) to the dissolved material, stirring, and filtering to remove the low molecular weight polymer, A method of washing once or twice or more with a solvent selected from water, acetone, methyl ethyl ketone and alcohol, and then neutralizing, washing with water, filtering and drying.

In the post-treatment methods exemplified in the above (1) to (3), the polyarylene sulfide resin may be dried in a vacuum or in an inert gas atmosphere such as air or nitrogen. May be. It is also possible to oxidatively crosslink the polyarylene sulfide resin by performing heat treatment in an oxidizing atmosphere having an oxygen concentration in the range of 5 to 30% by volume or under reduced pressure conditions.

The reaction in which polyarylene sulfide resin is produced by melt polymerization is exemplified below.

Reaction formulas (1) to (5) are, for example, polyphenylene when diphenyl disulfide having a substituent R containing a group represented by general formula (a), (b) or (c) is used as a polymerization inhibitor. It is an example of reaction which sulfide produces | generates. Reaction formula (1) is a reaction in which the —SS— bond in the polymerization inhibitor undergoes radical cleavage at the melting temperature. In the reaction formula (2), the sulfur radical generated in the reaction formula (1) attacks the adjacent carbon atom of the terminal iodine atom of the growing main chain, and the iodine atom is detached, so that the polymerization is stopped, In this reaction, a substituent R is introduced at the end of the main chain. Reaction formula (3) is a reaction in which a disulfide bond existing in the main chain of the polyarylene sulfide resin derived from the raw material (single sulfur) is radically cleaved at the melting temperature. In the reaction formula (4), the polymerization is stopped by recombination of the sulfur radical generated in the reaction formula (3) and the sulfur radical generated in the reaction formula (1), and the substituent R is at the end of the main chain. The reaction to be introduced. The detached iodine atom is in a free state (iodine radical), or iodine molecules are generated by recombination of iodine radicals as in reaction formula (5).

The reaction product containing polyarylene sulfide resin obtained by melt polymerization contains iodine atoms derived from the raw material. Therefore, the polyarylene sulfide resin is usually used for the preparation of a spinning resin composition in the form of a mixture containing iodine atoms. The concentration of iodine atoms in the mixture is, for example, in the range of 0.01 to 10,000 ppm, preferably in the range of 10 to 5000 ppm with respect to the polyarylene sulfide resin. It is also possible to keep the iodine atom concentration low by utilizing the sublimability of iodine molecules. In that case, it is possible to set the range to 900 ppm or less, preferably 100 ppm or less, and further 10 ppm or less. It is. Although it is possible to remove iodine atoms below the detection limit, it is not practical in view of productivity. The detection limit is, for example, about 0.01 ppm. The polyarylene sulfide resin of the present embodiment obtained by melt polymerization or the reaction product containing the same includes an iodine atom. It can be clearly distinguished from polyarylene sulfides obtained by legal methods.

As can be understood from the above reaction formula, the polyarylene sulfide resin obtained by melt polymerization is mainly composed of an arylene sulfide unit composed of an aromatic ring derived from a diiodo aromatic compound and a sulfur atom directly bonded thereto. It includes a main chain and a predetermined substituent R bonded to the end of the main chain. The predetermined substituent R is bonded to the aromatic ring at the end of the main chain directly or via a partial structure derived from a polymerization inhibitor.

The polyphenylene sulfide resin as the polyarylene sulfide resin according to one embodiment is, for example, the following general formula (10):

It has a main chain containing a repeating unit (arylene sulfide unit) represented by: The repeating unit represented by the formula (10) has the following formula (10a) bonded at the para position:

And the following unit (10b) bonded at the meta position:

It is more preferable that it is the repeating unit represented by these. Among these, a repeating unit bonded at the para position represented by the formula (10a) is preferable in terms of heat resistance and crystallinity of the resin.

The polyphenylene sulfide resin according to one embodiment has the following general formula (11):

(Wherein R ²⁰ and R ²¹ each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a nitro group, an amino group, a phenyl group, a methoxy group, or an ethoxy group.)
The repeating unit which has a substituent as a side chain couple | bonded with the aromatic ring represented by these may be included. However, it is preferable that the polyphenylene sulfide resin does not substantially contain the repeating unit of the general formula (11) from the viewpoints of crystallinity and heat resistance. More specifically, the ratio of the repeating unit represented by formula (11) is preferably based on the total of the repeating unit represented by formula (10) and the repeating unit represented by formula (11). It is 2 mass% or less, More preferably, it is 0.2 mass% or less.

The polyarylene sulfide resin of the present embodiment is mainly composed of the above arylene sulfide units, but usually derived from the elemental sulfur of the raw material, the following formula (20):

A structural unit related to a disulfide bond represented by the formula is also included in the main chain. From the viewpoint of heat resistance and mechanical strength, the proportion of the structural unit represented by the formula (20) is preferably 2 with respect to the total of the arylene sulfide unit and the structural site represented by the formula (20). The range is 9% by mass or less, and more preferably 1.2% by mass or less.

Mw / Mtop of the polyarylene sulfide resin according to the present embodiment is preferably in the range of 0.80 to 1.70, more preferably in the range of 0.90 to 1.30. By setting Mw / Mtop in such a range, the processability of the polyarylene sulfide resin can be improved and a good cavity balance can be imparted. In this specification, Mw represents the weight average molecular weight measured by gel permeation chromatography, and Mtop represents the average molecular weight (peak molecular weight) at the point where the detection intensity of the chromatogram obtained by the measurement is maximized. Mw / Mtop indicates the distribution of the molecular weight to be measured. Normally, when this value is close to 1, it indicates that the molecular weight distribution is narrow, and as this value increases, the molecular weight distribution is broad. The measurement conditions for gel permeation chromatography are the same as those in the examples of the present specification. However, it is possible to change the measurement conditions within a range that does not substantially affect the values of Mw and Mw / Mtop.

The weight average molecular weight of the polyarylene sulfide resin according to this embodiment is not particularly limited as long as the effects of the present invention are not impaired, but the lower limit thereof is 28,000 or more from the viewpoint of excellent mechanical strength. Is more preferable, and the range of 30,000 or more is more preferable. On the other hand, the upper limit is preferably in the range of 100,000 or less, more preferably in the range of 60,000 or less, and further in the range of 55,000 or less from the viewpoint that a better cavity balance can be imparted. Most preferably, it is in the range. Furthermore, from the viewpoint of providing excellent cavity balance while being excellent in mechanical strength, a polyarylene sulfide resin in the range of 28,000 to 60,000, more preferably in the range of 30,000 to 55,000. A polyarylene sulfide resin having a weight average molecular weight in the range of more than 60,000 and 100,000 or less may be used together with the polyarylene sulfide resin.

The non-Newtonian index of the polyarylene sulfide resin is preferably in the range of 0.95 to 1.75, more preferably in the range of 1.00 to 1.70. By setting the non-Newtonian index in such a range, the processability of the polyarylene sulfide resin can be improved and a good cavity balance can be imparted. In the present specification, the non-Newtonian index means an index satisfying the following relational expression between the shear rate and the shear stress under the condition of a temperature of 300 ° C. The non-Newtonian index can be an index relating to a molecular weight to be measured or a molecular structure such as linear, branched, or crosslinked. Usually, when this value is close to 1, it indicates that the molecular structure of the resin is linear, and as this value increases, more branches and cross-linked structures are included.
D = α × S ⁿ
(In the above formula, D represents shear rate, S represents shear stress, α represents a constant, and n represents a non-Newtonian index.)

The polyarylene sulfide resin having the above-mentioned specific ranges of Mw / Mtop and non-Newtonian index includes, for example, a diiodo aromatic compound, elemental sulfur, a polymerization inhibitor, a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor. In a method of reacting (solution polymerization) in a molten mixture containing a polyarylene sulfide resin, it can be obtained by increasing the molecular weight of the polyarylene sulfide resin to some extent.

The melting point of the polyarylene sulfide resin is preferably in the range of 250 to 300 ° C, more preferably in the range of 265 to 300 ° C. The melt viscosity (V6) at 300 ° C. of the polyarylene sulfide resin is preferably in the range of 1 to 2000 [Pa · s], more preferably in the range of 5 to 1700 [Pa · s]. Here, for the melt viscosity (V6), using a flow tester, an orifice having a temperature of 300 ° C., a load of 1.96 MPa, and a ratio of the orifice length to the orifice diameter (orifice length / orifice diameter) is 10/1. The melt viscosity after holding for 6 minutes.

The silicone compound used in the present embodiment is preferably a polyorganosiloxane represented by the following general formula (I) having a siloxane bond in the main chain.
R ³⁰ - ^{[Si (R} ₃₁₎ 2 -O] ⁿ 1 ^-R 32 (I)
(In the formula, R ³⁰ , R ³¹ and R ³² each independently represent a hydrogen atom or an organic group, and n ¹ is an integer of 2 or more.)

Among these, polydimethylsiloxane in which R ³⁰ , R ³¹ and R ^{32 in the} general formula (1) are all methyl groups is preferable, and a part of the methyl groups of the polydimethylsiloxane may be a hydrogen atom or other Those substituted with the above substituents are also preferred.

Examples of other substituents include alkyl groups having 2 or more carbon atoms, aryl groups, halogenated alkyl groups, silylalkyl groups, polyoxyalkylene groups, and reactive functional groups. When a plurality of methyl groups are substituted, From these, the same or different ones can be selected.

Examples of the alkyl group having 2 or more carbon atoms include an ethyl group, a propyl group, a butyl group, an octyl group, and a dodecyl group. Examples of the aryl group include a phenyl group, a tolyl group, and a naphthyl group.

Examples of the halogenated alkyl group include a fluoropropyl group and a chloropropyl group.

A typical example of the silylalkyl group is represented by the following general formula (II).
— (CH ₂ ) n ² —Si (OCH ₃ ) ₃ (II)
(In the formula, n ² is an integer of 1 or more.)

Specific examples of the polyoxyalkylene group include those represented by the following general formula (III).

-[CH ₂ ] kO- [C ₂ H ₄ O] 1- [C ₃ H ₆ O] m-R ³³ (III)
(Wherein k, l and m are each independently 0 or a positive integer, and l and m are simultaneously non-zero integers, and R ³³ is a hydrogen atom, an alkyl group, an aryl group, an alkyl halide) And one or more substituents selected from the group consisting of a group, a silylalkyl group, and a reactive functional group described later.)

The silicone compound preferably has a reactive functional group. Specific examples of the reactive functional group include an epoxy group, amino group, mercapto group, vinyl group, carboxyl group, hydroxyl group, isocyanate group, amide group, acyl group, nitrile group, and acid anhydride group. These reactive functional groups may be directly bonded to the main chain, or may be bonded to the terminal of an organic group such as an alkylene group or a polyoxyalkylene group bonded to the main chain. Among them, a carboxyl group, a hydroxyl group, an epoxy group, and an amino group are particularly preferable, and an epoxy group and an amino group are more preferable.

The silicone compound is effective in improving the durability against the electrolytic solution by being uniformly dispersed in the resin composition. From this viewpoint, the viscosity (25 ° C.) of the silicone compound is 10 to 100,000 mPa. · S is preferable, and an oily material in the range of 10 to 80,000 mPa · s is particularly preferable. In addition, in order to disperse | distribute a silicone compound uniformly in the resin composition of this embodiment, it is preferable to use what carried the silicone compound on inorganic powders, such as a silica.

When the reactive functional group is contained in the silicone compound, the silicone compound is favorably dispersed in the resin composition, so that the impact resistance can be improved. Furthermore, it is preferable also from the point which has the effect which suppresses what is called a bleed out that a silicone compound oozes out on the molded article surface.

The content of the reactive functional group in the silicone compound is preferably 400 g / equivalent (hereinafter abbreviated as “g / eq”) or more because it gives a favorable effect by imparting impact resistance and toughness. In terms of ease, 50,000 g / eq or less is preferable.

Further, the compounding amount of the silicone compound is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 5 parts by mass with respect to 100 parts by mass in total of the polyarylene sulfide resin and the silicone compound. More preferably, it is 0.5 to 3 parts by mass.

A silane compound may be blended in the gasket resin composition of the present embodiment. Examples of the silane compound include aminoalkoxysilane, epoxyalkoxysilane, and vinylalkoxysilane. These silane compounds can be used alone or in combination of two or more.

As the aminoalkoxysilane, any silane compound having one or more amino groups in one molecule and two or more alkoxy groups can be used. For example, γ-aminopropyltriethoxysilane, γ-aminopropyl Trimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) -γ-aminopropyltriethoxysilane, N-β (aminoethyl) -γ-aminopropyltri Methoxysilane, N-β (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltriethoxysilane, N- And phenyl-γ-aminopropyltrimethoxysilane.

As the epoxyalkoxysilane, any silane compound having one or more epoxy groups and two or more alkoxy groups in one molecule can be used. For example, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldimethoxysilane and the like.

As the vinylalkoxysilane, any silane compound having one or more vinyl groups and two or more alkoxy groups in one molecule can be used. For example, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris ( β-methoxyethoxy) silane and the like.

In the present embodiment, in addition to the above components, a fibrous reinforcing material or an inorganic filler may be added within a range that does not impair the effects of the present invention.

Examples of the fibrous reinforcing material include glass fiber, PAN-based or pitch-based carbon fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, aluminum borate fiber, titanic acid. Examples thereof include inorganic fibrous materials such as potassium fibers, stainless steel, aluminum, titanium, copper, brass, and other metallic fibrous materials, and organic fibrous materials such as aramid fibers.

Examples of inorganic fillers include silicates such as mica, talc, wollastonite, sericite, kaolin, clay, bentonite, asbestos, alumina silicate, zeolite, pyrophyllite, and carbonates such as calcium carbonate, magnesium carbonate, and dolomite, Examples thereof include sulfates such as calcium sulfate and barium sulfate, metal oxides such as alumina, magnesium oxide, silica, zirconia, titania and iron oxide, glass beads, ceramic beads, boron nitride, silicon carbide, and calcium phosphate. These fibrous reinforcing materials and inorganic fillers can be used alone or in combination of two or more.

In addition, the resin composition for a gasket of the present embodiment includes an antioxidant, a stabilizer, a processing heat stabilizer, a plasticizer, a release agent, a colorant, a lubricant, and a weather resistance as long as the effects of the present invention are not impaired. An appropriate amount of a stabilizer, a foaming agent, a rust inhibitor, and a wax may be blended.

Furthermore, the resin composition for gaskets of the present embodiment may be appropriately mixed with other resin components in accordance with required characteristics. Examples of the resin component that can be used here include ethylene, butylene, pentene, butadiene, isoprene, chloroprene, styrene, α-methylstyrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, (meth) acrylonitrile, and the like. Monomers or copolymers of monomers, polyesters such as polyurethane, polybutylene terephthalate, polyethylene terephthalate, polyacetal, polycarbonate, polysulfone, polyallylsulfone, polyethersulfone, polyphenylene ether, polyetherketone, poly Homopolymers such as ether ether ketone, polyimide, polyamideimide, polyetherimide, silicone resin, epoxy resin, phenoxy resin, liquid crystal polymer, polyaryl ether, Dam or block copolymer, and graft copolymer and the like.

Specifically, as a method for producing the resin composition for gaskets of the present embodiment, a silicone compound, a polyarylene sulfide resin, and other blending components blended as necessary are uniformly mixed with a tumbler, a Henschel mixer, or the like. Then, the mixture is put into a twin screw extruder, and the ratio (discharge amount / screw rotation number) between the resin component discharge amount (kg / hr) and the screw rotation speed (rpm) is 0.02 to 0.2. Examples of the method include melt kneading under a condition of (kg / hr · rpm).

The above production method will be described in more detail. A method in which the above-described components are put into a twin-screw extruder and melt-kneaded under temperature conditions of a preset temperature of 330 ° C. and a resin temperature of about 350 ° C. can be mentioned. At this time, the discharge amount of the resin component is in the range of 5 to 50 kg / hr at a rotational speed of 250 rpm. In particular, it is preferably 20 to 35 kg / hr from the viewpoint of dispersibility. Therefore, the ratio (discharge amount / screw rotation number) between the resin component discharge amount (kg / hr) and the screw rotation speed (rpm) is particularly 0.08 to 0.14 (kg / hr · rpm). Is preferred.

The resin composition for a gasket thus melt-kneaded is usually cut into a pellet form. Further, the obtained pellet is supplied to a molding machine and melt-molded to finally obtain a molded product having a desired shape.

Here, examples of the melt molding method include injection molding, extrusion molding, and compression molding. Among these, the injection molding is particularly preferable as a method of molding the secondary battery gasket.

The resin composition for gaskets of the present embodiment is a secondary battery used for electric devices such as notebook computers, mobile phones and video cameras, or in-vehicle applications such as hybrid vehicles (HV) and electric vehicles (EV). In particular, it is particularly useful for gaskets for high capacity lithium ion secondary batteries.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

1. Polyphenylene sulfide resin (PPS resin)
1-1. Synthesis of PPS-1 to 5 (Synthesis Example 1)
30-0.0 g of p-diiodobenzene (Tokyo Kasei Co., Ltd., p-diiodobenzene purity of 98.0% or more), solid sulfur (sulfur (powder) manufactured by Kanto Chemical Co., Inc.) 27.00 g, 4,4′- Dithiobisbenzoic acid (4,4′-dithiobisbenzoic acid, Technical Grade, manufactured by Wako Pure Chemical Industries, Ltd.) (2.0 g) was heated to 180 ° C. in a nitrogen atmosphere, and these were dissolved and mixed. Next, the temperature was raised to 220 ° C., and the pressure was reduced to an absolute pressure of 26.6 kPa. Melt polymerization was carried out for 8 hours while heating the obtained molten mixture while changing the temperature and pressure stepwise so that the inside pressure was 320 ° C. and the absolute pressure was 133 Pa. After completion of the reaction, 200 g of NMP was added, and the mixture was heated and stirred at 220 ° C., and the resulting dissolved product was filtered. 320 g of NMP was added to the lysate after filtration, and cake washing filtration was performed. 1 L of ion-exchanged water was added to the obtained cake containing NMP, and the mixture was stirred in an autoclave at 200 ° C. for 10 minutes. Next, the cake was filtered, and 1 L of ion-exchanged water at 70 ° C. was added to the cake after filtration to wash the cake. 1 L of ion-exchanged water was added to the obtained water-containing cake and stirred for 10 minutes. Next, the cake was filtered, and 1 L of ion-exchanged water at 70 ° C. was added to the cake after filtration to wash the cake. After repeating this operation once more, the cake was dried at 120 ° C. for 4 hours to obtain 91 g of PPS resin.

(Synthesis Example 2)
91 g of PPS resin was obtained in the same manner as in Synthesis Example 1 except that “2-iodoaniline (manufactured by Tokyo Chemical Industry Co., Ltd.)” was used instead of “4,4′-dithiobisbenzoic acid”.

(Synthesis Example 3)
91 g of PPS resin was obtained in the same manner as in Synthesis Example 1 except that “diphenyl disulfide (Sumitomo Seika Chemicals, DPDS)” was used instead of “4,4′-dithiobisbenzoic acid”.

(Synthesis Example 4)
30-0.0 g of p-diiodobenzene (manufactured by Tokyo Chemical Industry Co., Ltd., p-diiodobenzene purity of 98.0% or more), 29.15 g of solid sulfur (manufactured by Kanto Chemical Co., Inc., sulfur (powder)) and 4-iodobiphenyl 1.48 g (manufactured by Tokyo Chemical Industry Co., Ltd.) was heated to 180 ° C. in a nitrogen atmosphere, and these were dissolved and mixed. Next, the temperature is raised to 220 ° C., the pressure is reduced to 46.7 kPa, and the temperature and pressure are changed stepwise so that the system has an absolute pressure of 320 Pa at 320 ° C., and the resulting molten mixture is heated. Then, melt polymerization was performed for 8 hours. After completion of the reaction, 200 g of NMP was added, and the mixture was heated and stirred at 220 ° C., and the resulting dissolved product was filtered. 320 g of NMP was added to the lysate after filtration, and cake washing filtration was performed. 1 L of ion-exchanged water was added to the obtained cake containing NMP, and the mixture was stirred in an autoclave at 200 ° C. for 10 minutes. Next, the cake was filtered, and 1 L of ion-exchanged water at 70 ° C. was added to the cake after filtration to wash the cake. 1 L of ion-exchanged water was added to the obtained water-containing cake and stirred for 10 minutes. Next, the cake was filtered, and 1 L of ion-exchanged water at 70 ° C. was added to the cake after filtration to wash the cake. After repeating this operation once more, the cake was dried at 120 ° C. for 4 hours to obtain 91 g of PPS resin.

(Comparative synthesis example)
NMP (600 g) and sodium sulfide pentahydrate (336.3 g (2.0 mol)) were charged, and the mixture was heated to 200 ° C. under a nitrogen atmosphere to distill off the water-NMP mixture. Next, a solution prepared by dissolving 292.53 g of p-dichlorobenzene and 1.62 g of 2,5-dichloroaniline in 230 g of NMP was added to this system and reacted at 220 ° C. for 5 hours and further at 240 ° C. for 2 hours in a nitrogen atmosphere. After cooling the reaction vessel, the contents were taken out, a part was sampled, and unreacted 2,5-dichloroaniline was quantified by gas chromatography. The remaining slurry was washed several times with hot water, and the polymer cake was filtered off. This cake was dried under reduced pressure at 80 ° C. to obtain a powdery PPS resin. When an infrared absorption spectrum was measured, an absorption spectrum which was considered to be derived from an amino group was observed in the vicinity of 3380 cm ⁻¹ .

1-2. Melt viscosity PPS resin was measured for 6 minutes using a flow tester CFT-500C manufactured by Shimadzu Corporation at 300 ° C., load: 1.96 × 10 ⁶ Pa, L / D = 10/1, and then the melt viscosity was measured. .

1-3. Non-Newtonian index PPS resin was measured with a capillary rheometer at a temperature of 300 ° C. using a die having a diameter of 1 mm and a length of 40 mm for a shear rate of 100 to 1000 (sec ⁻¹ ). Is a value calculated from the slope of the logarithm plot.

1-4. Mw and Mw / Mtop (molecular weight distribution)
The weight average molecular weight and peak molecular weight of the PPS resin were measured under the following measurement conditions using gel permeation chromatography. Mw / Mtop was calculated from the obtained Mw and Mtop. Six types of monodisperse polystyrene were used for calibration.
Apparatus: Ultra-high temperature polymer molecular weight distribution analyzer ("SSC-7000" manufactured by Senshu Kagaku Co., Ltd.)
Column: UT-805L (made by Showa Denko KK)
Column temperature: 210 ° C
Solvent: 1-chloronaphthalene Measurement method: UV detector (360 nm)

The properties of synthesized PPS-1 to 5 are summarized in Table 1.

2. Polyphenylene sulfide resin composition (PPS compound)
2-1. Raw materials In order to prepare the PPS resin composition, the following silicone compounds were prepared.
Si-1: Silicone powder (Toray Doll Corning Co., Ltd., “Trefil F-202”, Silica oil (viscosity (25 ° C.) 62 Pa · s) 60% by mass) supported on silica)
Si-2: amino group-containing silicone (“KF-868” manufactured by Shin-Etsu Chemical Co., Ltd.)

2-2. Compound preparation Each raw material was uniformly mixed using a tumbler with the composition shown in Table 2, and then melt kneaded at 300 ° C using a twin-screw kneading extruder ("TEM-35B" manufactured by Toshiba Machine Co., Ltd.). Thus, a pellet-like compound was obtained.

3. Evaluation 3-1. Tensile Strength and Tensile Elongation Evaluation moldings obtained by injection molding into the ASTM No. 4 dumbbell shape from the obtained compound were subjected to tensile elongation at break using “Autograph AG-5000C” manufactured by Shimadzu Corporation according to ASTM D638. It was measured.

3-2. Compressive stress relaxation test Resin composition pellets are molded using an injection molding machine, and a flat plate of 8 mm length × 8 mm width × 3 mm thickness is molded by an injection molding machine, and a test piece for compressive stress relaxation as shown in FIG. Produced. Using this test piece, the compression stress relaxation was measured under 10% strain (temperature conditions: 23 ° C. and 60 ° C.) by “Autograph AG-50KNX” manufactured by Shimadzu Corporation equipped with a thermostatic bath. The compressive stress was determined.

3-3. Evaluation of airtightness The resin composition pellets were molded using an injection molding machine to produce a box-shaped product having a shape of 8 mm long × 8 mm wide × 10 mm high and 0.8 mm thick. Next, an electrolytic solution (1 mol / L LiPF6 / ethylene carbonate (EC): dimethyl carbonate (DMC) (capacity 1: 1 mixed solution) solution, manufactured by Kishida Chemical Co., Ltd.)) is put into this box forming product, and the compression stress relaxation is performed. An airtightness test sample sealed with a constant stress (under 10% strain) on a flat plate of 8 mm length × 8 mm width × 3 mm thickness used in the test is prepared. This was left for 100 hours under dry heat at 60 ° C., and the liquid leakage was confirmed. The evaluation results were displayed as follows.
○: No liquid leakage occurs after 100 hours.
X: Liquid leakage occurs after 100 hours.

3-4. Cavity Balance Using a washer mold having 40 cavities, the PPS compound was injection molded under the lowest molding conditions as long as the cavity (C1) closest to the primary sprue was completely filled. The molding conditions were a 75-ton molding machine, a cylinder temperature of 320 ° C, a mold temperature of 140 ° C, and no holding pressure.
The degree of filling of the cavity (C10) farthest from the primary sprue in the same runner as the cavity (C1) after molding was compared. The degree of filling (% by mass) was determined from the mass ratio of the molded product of the cavity (C10) to the molded product of the cavity (C1). It can be said that the higher the degree of filling of the cavity (C10), the better the cavity balance. Based on the degree of filling, the cavity balance of each composition was determined according to the following criteria.
AA: 100 to 90% by mass
A: 89-80% by mass
B: 79 to 70% by mass
C: 69-60 mass%
D: 59% or less

3-5. Generated Gas Amount Using a gas chromatograph mass spectrometer, for a single PPS resin and a PPS compound, a predetermined amount of sample was heated at 325 ° C. for 15 minutes, and the amount of generated gas at that time was quantified as mass%.

As is apparent from the results shown in Table 2, the resin compositions prepared in the examples have excellent cavity balance, high mechanical strength, and can form molded products with excellent airtightness. When used, the airtightness required for the secondary battery can be maintained.

Claims

A resin composition for a gasket used for a secondary battery composed of a positive electrode, a negative electrode, a sealing body, a gasket, a separator, and an electrolyte solution,
Containing a polyarylene sulfide resin and a silicone compound,
The polyarylene sulfide resin comprises reacting a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor in a molten mixture containing the diiodo aromatic compound, the elemental sulfur, and the polymerization inhibitor. The resin composition for gaskets which can be obtained by this.
The resin composition for a gasket according to claim 1, wherein the polyarylene sulfide resin has at least one group selected from the group consisting of a hydroxy group, an amino group, a carboxyl group and a carboxyl group salt derived from the polymerization inhibitor. object.
The polyarylene sulfide resin has a non-Newtonian index of 0.95 to 1.75 at 300 ° C. and Mw / Mtop of 0.80 to 1.70;
The resin composition for a gasket according to claim 1 or 2, wherein the Mw and Mtop are respectively a weight average molecular weight and a peak molecular weight measured by gel permeation chromatography.
A gasket for a secondary battery comprising the resin composition for a gasket according to any one of claims 1 to 3.
A method for producing a resin composition for a gasket used in a secondary battery comprising a positive electrode, a negative electrode, a sealing body, a gasket, a separator, and an electrolyte solution,
Having a step of mixing a polyarylene sulfide resin and a silicone compound,
The polyarylene sulfide resin comprises reacting a diiodo aromatic compound, elemental sulfur, and a polymerization inhibitor in a molten mixture containing the diiodo aromatic compound, the elemental sulfur, and the polymerization inhibitor. The manufacturing method of the resin composition for gaskets which can be obtained by this.
The resin composition for a gasket according to claim 5, wherein the polyarylene sulfide resin has at least one group selected from the group consisting of a hydroxy group, an amino group, a carboxyl group, and a carboxyl group salt derived from the polymerization inhibitor. Manufacturing method.
The polyarylene sulfide resin has a non-Newtonian index of 0.95 to 1.75 at 300 ° C. and Mw / Mtop of 0.80 to 1.70;
The method for producing a resin composition for a gasket according to claim 5 or 6, wherein Mw and Mtop are respectively a weight average molecular weight and a peak molecular weight measured by gel permeation chromatography.