JP2001294745A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material having excellent weld properties while maintaining creep characteristics at a high temperature. SOLUTION: The resin composition comprises (a) a polyphenylene ether-based resin, (b) a polypropylenic resin and (c) a hydrogenated block copolymer obtained by hydrogenating a block copolymer comprising at least two polymer blocks A mainly composed of a vinyl aromatic compound and at least one polymer block B mainly composed of a conjugated diene compound, where the molecular weight distribution of the polypropylenic resin in the resin composition is at least 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent weld properties and creep properties used in the fields of automobiles, electric / electronics, and various other industrial materials.

[0002]

2. Description of the Related Art For the purpose of improving the impact resistance and the like of polyphenylene ether, for example, U.S. Pat. No. 3,361,851 proposes blending polyphenylene ether with polyolefin, for example, electric / electronic parts, office equipment housing, automobile parts, and the like. Widely used as resin compositions for precision parts and various industrial parts. However, the polyphenylene ether resin composition comprising the polyphenylene ether and the polyolefin has a shortage of compatibility, and has a disadvantage that the weld properties are particularly low.

[0003] For example, Japanese Patent Application Laid-Open No. 6-9828 proposes to improve the weld properties by using a polyolefin resin having a specific controlled molecular weight and molecular weight distribution. Now, the polyphenylene ether resin composition comprising the polyphenylene ether and the polyolefin is widely used as a battery case component.Recently, particularly in a battery case for an electric vehicle, etc., it is excellent in creep characteristics at high temperatures. It has been demanded.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a material having excellent weld properties and maintaining high temperature creep properties.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have solved the above problems by controlling the molecular weight distribution of the polypropylene resin in the resin composition to a specific one. The inventors have found that the problem can be solved, and have reached the present invention.

That is, the present invention relates to (1) (a) a polyphenylene ether-based resin, (b) a polypropylene-based resin, and (c) a polymer block A mainly composed of at least two vinyl aromatic compounds and a conjugated diene compound. A resin composition comprising a hydrogenated block copolymer obtained by hydrogenating a block copolymer comprising at least one polymer block B as a main component, and a molecular weight distribution of a polypropylene resin in the resin composition. Is not less than 8, a resin composition,

(2) The resin composition according to (1), wherein the molecular weight distribution of the polypropylene resin in the resin composition is 9 or more, and (3) components (a) and (b) are weight (A) / (b) = 10/90 to 70/30 in ratio, and (c) with respect to a total of 100 parts by weight of the components (a) and (b)
The resin composition according to (1) or (2), wherein the component is 3 to 40 parts by weight, and (4) (a) the polyphenylene ether-based resin has a weight average molecular weight of 10,000 or more. (1) to (3), and (5) a material for a battery case component comprising the resin composition according to any of (1) to (4).
Hereinafter, the present invention will be described in detail.

The (a) polyphenylene ether-based resin (hereinafter abbreviated as PPE) used in the present invention has the general formula (1)

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Wherein R1, R2, R3 and R4 are each hydrogen, halogen, a primary or secondary lower alkyl group having 1 to 7 carbon atoms, a phenyl group, a haloalkyl group, an aminoalkyl group, A hydrogenoxy group or a halohydrocarbonoxy group in which at least two carbon atoms separate a halogen atom and an oxygen atom, which may be the same or different from each other) The reduced viscosity (0.5 g / dl, chloroform solution, measured at 30 ° C.) is preferably in the range of 0.15 to 0.70, more preferably 0.20 to 0.70.
Homopolymers and / or copolymers in the range of 60.

The PPE preferably has a polystyrene equivalent weight average molecular weight of 10,000 or more. When the weight average molecular weight is less than 10,000, productivity and color tone are lowered, which is not preferable. This weight average molecular weight can usually be known by gel permeation chromatography or the like.

Specific examples of the PPE include poly (2,6-dimethyl-1,4-phenylene ether), poly (2-methyl-6-ethyl-1,4-phenylene ether), (2-methyl-6-phenyl-
1,4-phenylene ether), poly (2,6-dichloro-1,4-phenylene ether), and the like. Further, 2,6-dimethylphenol and other phenols (for example, 2,3,6-trimethyl) Polyphenylene ether copolymers such as phenol and 2-methyl-6-butylphenol). Among them, poly (2,6-dimethyl-1,4-phenylene ether),
Copolymers of 2,6-dimethylphenol and 2,3,6-trimethylphenol are preferred, and poly (2,6-dimethylphenol) is more preferred.
6-dimethyl-1,4-phenylene ether) is preferred.

The method for producing PPE used in the present invention is not particularly limited as long as it can be obtained by a known method. For example, a method for preparing copper (P) chloride and an amine by Hay described in US Pat. The complex can be easily produced by oxidative polymerization of 2,6-dimethylphenol using the complex as a catalyst. In addition, U.S. Patent Nos. 3,306,875 and 3,257,357.
No. 3,257,358, Japanese Patent Publication No. 52
It can be easily produced by the methods described in JP-A-17880, JP-A-50-51197 and JP-A-63-152628.

[0013] The PPE used in the present invention may be a mixture of the above-mentioned PPE and a styrene monomer and / or an α, β-unsaturated carboxylic acid or a derivative thereof in the absence of a radical generator. A known modification obtained by reacting under a temperature of 80 to 350 ° C. in a molten state, a solution state, or a slurry state (the styrene-based monomer and / or the α, β-unsaturated carboxylic acid and its derivative are present in an amount of 0.1 to 1%). 01 to 10% by weight graft or addition)
PPE may be used, and a mixture of the above-mentioned PPE and the modified PPE at an arbitrary ratio may be used.

The PPE used in the present invention is the above-mentioned PPE.
In addition to PE, those obtained by adding polystyrene (including syndiotactic polystyrene) or high-impact polystyrene to 100 parts by weight of these PPEs in a range not exceeding 400 parts by weight can be suitably used.
Further, polyphenylene ether used in the present invention,
The organic solvent resulting from the polymerization solvent may remain in an amount of less than 5% by weight based on 100 parts by weight of the polyphenylene ether. Organic solvents caused by these polymerization solvents,
It is difficult to completely remove it in the drying step after the polymerization, and usually, it remains in the range of several hundred ppm to several%. As the organic solvent resulting from the polymerization solvent here,
Examples include at least one of toluene, xylene isomers, ethylbenzene, C1-5 alcohols, chloroform, dichloromethane, chlorobenzene, and dichlorobenzene.

Next, the polypropylene resin (b) will be described in detail. The (b) polypropylene-based resin used in the present invention comprises a crystalline propylene homopolymer and a crystalline propylene homopolymer portion obtained in the first step of polymerization and propylene, ethylene and / or at least one A crystalline propylene-ethylene block copolymer having a propylene-ethylene random copolymer portion obtained by copolymerizing other α-olefins (eg, butene-1, hexene-1 and the like); It may be a mixture of a propylene homopolymer and a crystalline propylene-ethylene block copolymer.

The polypropylene-based resin is usually used at a polymerization temperature of 0 to 100 ° C. in the presence of an alkylaluminum compound and a titanium halide catalyst supported on a carrier such as a titanium trichloride catalyst or magnesium chloride. It is obtained by polymerization in the range of 3 to 100 atm. On this occasion,
It is also possible to add a chain transfer agent such as hydrogen to adjust the molecular weight of the polymer, and it is also possible to use a batch method or a continuous method as a polymerization method, such as butane, pentane, hexane, heptane, and octane. A method such as solution polymerization or slurry polymerization in a solvent can also be selected, and a bulk polymerization in a monomer without a solvent, a gas phase polymerization in a gaseous monomer, and the like can be applied.

In addition to the above-mentioned polymerization catalyst, an electron-donating compound can be used as an internal donor component or an external donor component as a third component in order to increase the isotacticity and polymerization activity of the obtained polypropylene. As these electron donating compounds, known compounds can be used, for example, ester compounds such as ε-caprolactone, methyl methacrylate, ethyl benzoate, and methyl toluate; and triphenyl phosphite and tributyl phosphite. Phosphoric acid derivatives such as phosphoric acid esters and hexamethylphosphoric triamide, alkoxy ester compounds, aromatic monocarboxylic acid esters and / or aromatic alkyl alkoxy silanes, aliphatic hydrocarbon alkoxy silanes, various ether compounds, various alcohols And / or various phenols.

In general, in a polypropylene-polyphenylene ether-based polymer alloy, increasing the molecular weight of the polypropylene-based resin improves the high-temperature creep characteristics, but decreases the weld strength. There is a conflicting phenomenon that characteristics are reduced. In order to achieve both high-temperature creep characteristics and weld strength, which are the objects of the present invention, it is important to increase the molecular weight distribution of the polypropylene resin.

The molecular weight distribution of the polypropylene resin used in the present invention is 8 or more in the resin composition after melt-kneading.
Preferably it is 9 or more. When the molecular weight distribution is less than 8, the high temperature creep properties are deteriorated. This molecular weight distribution can usually be known by gel permeation chromatography or the like. The upper limit of the molecular weight distribution is not limited,
If it exceeds 15, the fluidity is reduced, and the physical properties of the weld are reduced. The polypropylene resin of the present invention can be used having any crystallinity or melting point as long as it can be obtained by the above-described method, and it is also possible to use several types of polypropylene having different crystallinity and melting point, and different molecular weights. it can.

The density of the propylene polymer in the polypropylene resin of the present invention is 0.900 g / cm.
³ or more and 0.900 to 0.935 g / cm ³ , more preferably 0.90 to 0.925 g / cm ³
And most preferably 0.908 to 0.915 g /
cm ³ . If the density is less than 0.906 g / cm ^3, inferior strength, those exceeding 0.935 g / cm ³ is difficult to manufacture. The measuring method of density is JIS K-7
It can be easily obtained by the 112 underwater substitution method. Further, the density of the propylene polymer portion in the resin composition, the resin composition was extracted using polyphenylene ether such as chloroform or a good solvent of a hydrogenated block copolymer, and the remaining polypropylene-based resin was extracted from the above-mentioned resin composition. Can be determined by the following method.

In the present invention, it is also effective to add a known nucleating agent. Any crystal nucleating agent may be used as long as it improves the crystallinity of the polypropylene resin, but typical examples include metal salts of aromatic carboxylic acids, sorbitol derivatives, organic phosphates, aromatic amide compounds, and the like. Organic nucleating agent and inorganic nucleating agent such as talc. However, it is not limited to these.

The preferred ratio of (a) the polyphenylene ether resin component and (b) the polypropylene resin component of the present invention is (a) / (b) in a weight ratio of 10/90 to 70 /.
30, more preferably from 20/80 to 60/40, most preferably from 30/70 to 50/50.

Next, the component (c) will be described in detail.
(C) A block copolymer comprising at least two polymer blocks A mainly composed of at least two vinyl aromatic compounds and at least one polymer block B mainly composed of a conjugated diene compound is hydrogenated. Hydrogenated block copolymer (hereinafter abbreviated as hydrogenated block copolymer)
Is necessary to obtain a resin composition having excellent creep strength at high temperatures, and when (a) a polyphenylene ether-based resin and (b) a polypropylene-based resin are melt-mixed, (a) a polyphenylene ether-based resin is used. Resin (b)
It is a hydrogenated block copolymer having the ability to be suitably dispersed in a polypropylene resin. The structures of these hydrogenated block copolymers are, for example, ABA, ABA-
It is a hydrogenated block copolymer having a structure such as B, (AB-) _4- Si, ABAABA, or the like.

It is to be noted that a so-called 2 is composed of one polymer block mainly composed of a vinyl aromatic compound and one polymer block mainly composed of a conjugated diene compound.
When a hydrogenated block copolymer having a type (AB type) structure is used, the miscibility when melt-kneading a polypropylene resin and polyphenylene ether is excellent, but the creep strength and tensile elongation at high temperatures are reduced. Is not preferred.

The polymer block A mainly composed of a vinyl aromatic compound and the polymer block B mainly composed of a conjugated diene compound are each composed of a conjugated diene compound or a vinyl aromatic compound in the molecular chain of each polymer block. The distribution of the compound may be random, tapered (the monomer component increases or decreases along the molecular chain), partially block-like, or any combination thereof, and the polymer block mainly composed of the vinyl aromatic compound is 2 More than
The number of the polymer blocks mainly composed of the conjugated diene compound is one or more, and the respective polymer blocks may have the same structure or different structures.

The vinyl aromatic compound constituting the block copolymer is, for example, one or more of styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene, diphenylethylene and the like. It can be selected, and styrene is particularly preferred. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, and 2,3-dimethyl-1,3.
-One or more of butadiene and the like are selected, butadiene, isoprene and a combination thereof are particularly preferred.

The polymer block mainly composed of a conjugated diene compound can have any desired microstructure. For example, in a polymer block mainly composed of butadiene, 1,2-vinyl bond has 5 ~ 9
5%, preferably 10-90%, more preferably 35%
~ 85%. In the polymer block mainly composed of isoprene, the 3,4-vinyl bond has 3 to 80 bonds.
%, Preferably 5 to 70%.

The amount of the polymer block A mainly composed of a vinyl aromatic compound in the hydrogenated block copolymer is preferably 10 to 90% by weight based on the weight of the hydrogenated block copolymer.
More preferably 15 to 80% by weight, even more preferably 3% by weight.
0 to 70% by weight. These (c) hydrogenated block copolymers may be obtained by any production method as long as they have the above-mentioned structure.

The (c) hydrogenated block copolymer used in the present invention is, in addition to the above-mentioned hydrogenated block copolymer,
The hydrogenated block copolymer and an α, β-unsaturated carboxylic acid or a derivative thereof are heated to 80 to 350 ° C. in a molten state, a solution state, or a slurry state in the presence or absence of a radical generator.
A known modification (the α, β-unsaturated carboxylic acid or a derivative thereof is 0.1%) obtained by reacting at the temperature of
(Graft or addition of 0 to 10% by weight) may be a hydrogenated block copolymer, or a mixture of the above-mentioned hydrogenated block copolymer and the modified hydrogenated block copolymer in any ratio. Absent.

The preferred amount of (c) the hydrogenated block copolymer is 3 to 40 parts by weight, more preferably 5 to 20 parts by weight, based on 100 parts by weight of the total of the above components (a) and (b).
Most preferably, it is 6 to 15 parts by weight. If the compounding amount is less than 3 parts by weight, the effect as an admixture is not seen, which is not preferable. If the amount exceeds 40 parts by weight, the heat and solvent resistance, rigidity and mechanical strength of the components (a) and (b) are markedly reduced, which is not preferable.

In the present invention, in addition to the above components, other additional components such as an antioxidant, a metal deactivator, and a flame retardant (organic) may be used as long as the characteristics and effects of the present invention are not impaired. Phosphate ester compounds, inorganic phosphorus compounds, aromatic halogen flame retardants, silicone flame retardants, etc.), fluoropolymers, plasticizers (oil, low molecular weight polyethylene, epoxidized soybean oil, polyethylene glycol, fatty acid esters, etc.) ), Flame retardant aids such as antimony trioxide, weather (light) improvers, slip agents, inorganic or organic fillers and reinforcements (glass fibers, glass flakes, carbon fibers, polyacrylonitrile fibers, whiskers, mica,
Talc, carbon black, titanium oxide, calcium carbonate, potassium titanate, wollastonite, conductive metal fibers, conductive carbon black, etc.), various coloring agents, release agents, and the like.

In the method for producing the resin composition of the present invention, (a) a mixture obtained by previously kneading (a) a polyphenylene ether-based resin and (c) a hydrogenated block copolymer using the above-described components, and A method of melt-kneading together with a polypropylene resin, (c) a part of the hydrogenated block copolymer is previously kneaded with (b) a polypropylene resin or (a) a polyphenylene ether resin, and these pre-kneaded products are again Melt kneading together, (a) polyphenylene ether-based resin and (c) hydrogenated block copolymer are supplied from the first feed port of the extruder, and the intermediate port of the extruder is introduced into these compositions in a molten state. (B) a method of supplying and melting and kneading a polypropylene resin, and (a) a polyphenylene ether resin and (b) a polypropylene resin from the first feed port of an extruder. A method in which (c) a hydrogenated block copolymer and the remaining (b) a polypropylene-based resin are supplied from an intermediate port of an extruder into a part of these compositions in a molten state, and melt-kneaded. (A) Polyphenylene ether-based resin and (c) a part of the hydrogenated block copolymer are supplied from the first feed port, and (b) polypropylene-based resin is fed into the molten state of the composition from the middle port of the extruder. And the remaining (c) hydrogenated block copolymer is supplied and melt-kneaded.

As these methods, for example, a single screw extruder,
Examples of the method include a hot-melt kneading method using a twin-screw extruder, a roll, a kneader, a Brabender plastograph, a Banbury mixer, etc., and a melt-kneading method using a twin-screw extruder is most preferable. The melt-kneading temperature at this time is not particularly limited, but can be arbitrarily selected from the range of usually 200 to 380 ° C.

The resin composition of the present invention can be suitably used for a battery case material, particularly a sealed case for a secondary battery, particularly a nickel hydrogen battery. The molding method is not particularly limited, and for example, molding methods such as injection molding, hollow molding, extrusion molding, sheet molding, thermoforming, rotational molding, and lamination molding can be used.

When the battery case is made up of two or more parts, these parts are joined by bonding, heat welding, vibration welding or the like. Examples of the adhesive include an epoxy resin adhesive. The epoxy resin adhesive is an adhesive made of a resin having an epoxy structure as a main skeleton, and is preferably a two-pack type made of a main agent and a curing agent. The resin composition of the present invention obtained in this manner can be used for applications other than the battery case material.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to examples, but the present invention is not limited to these examples. In addition, the raw materials used are as follows. (A) Polyphenylene ether resin Polyphenylene ether having a reduced viscosity of 0.54, obtained by oxidative polymerization of 2,6-xylenol.

(B) Polypropylene resin (b-1) Density = 0.910 g / cm ³ , melt flow rate (230 ° C., 21.2 N load: hereinafter abbreviated as MFR)
= 0.4 g / 10 min, molecular weight distribution (Mw / Mn) = 1
2.0 polypropylene resin (b-2) Density = 0.906 g / cm ³ , MFR = 70
g / 10 minutes, polypropylene resin with molecular weight distribution (Mw / Mn) = 5.9 (b-3) Density = 0.910 g / cm ³ , MFR = 2.
0/10 min, polypropylene resin with molecular weight distribution (Mw / Mn) = 11.9 (b-4) Density = 0.904 g / cm ³ , MFR = 0.
5 g / 10 min, molecular weight distribution (Mw / Mn) = 6.2 polypropylene resin

(C) hydrogenated block copolymer having a structure of polystyrene-hydrogenated polybutadiene-polystyrene, having a bound styrene content of 43%, a 1,2-vinyl bond content of the polybutadiene portion of 78%, and a polystyrene chain A hydrogenated block copolymer having a number average molecular weight of 19000. The evaluation of physical properties was performed as follows.

(1) Deflection temperature under load Measured under a load of 1.8 MPa according to ASTM D648. (2) Weld physical properties Using a mold capable of forming a weld part, a test piece for tensile test (ASTM having a weld part in the center)
A type I dumbbell piece; 1/8 inch thick) is injection molded and subjected to a tensile test (ASTM D-638) to determine the weld strength retention (the tensile strength of a test piece with a welded part ÷ the test piece without a welded part) Tensile strength × 100%).

(3) High temperature creep strength creep tester (145-B, manufactured by Yasuda Seiki Seisakusho KK)
-PC type), using a 4 mm x 1 mm x 7 cm tank, with a stress of 12.25 M between 40 mm between the chucks.
A creep test was performed at a temperature of 80 ° C. for 2 weeks under a load equivalent to Pa, and the presence or absence of fracture was confirmed.

[0041]

EXAMPLES 1-4 AND COMPARATIVE EXAMPLE 1 A polypropylene resin, a polyphenylene ether resin, and a hydrogenated block copolymer were blended according to the composition shown in Table 1, and twin screw extrusion with a vent port was set at 260-280 ° C. Machine (ZSK-25;
(WERNER & PFLEIDERER, Germany)
To obtain a pellet. The pellets are supplied to a screw in-line injection molding machine set at 240 to 280 ° C, and a test piece for a tensile test, a test piece for measuring a deflection temperature under load and a test piece for a creep test are prepared under the condition of a mold temperature of 60 ° C. Injection molded. The physical properties of these test pieces were measured, and the results are shown in Table 1.

In order to measure the molecular weight distribution of the polypropylene resin in the resin composition after the melt-kneading, the extruded pellets were extracted by refluxing with xylene, and then gradually cooled to room temperature to precipitate the polypropylene resin. The precipitate was separated by filtration and dried, and the polypropylene resin was separated from the composition. The molecular weight distribution of the separated polypropylene resin was determined by gel permeation chromatography [150-
C ALC / GPC (manufactured by Waters)] (solvent: 1,
2,4-Trichlorobenzene, temperature: 140 ° C., column: AT-807S (manufactured by Showa Denko KK), polyethylene equivalent molecular weight).

[0043]

[Table 1]

[0044]

Industrial Applicability The composition of the present invention has excellent weld properties and also has excellent high temperature creep properties.

Claims (5)

[Claims] (A) a polyphenylene ether-based resin,
A block copolymer comprising (b) a polypropylene resin and (c) at least two polymer blocks A mainly composed of a vinyl aromatic compound and at least one polymer block B mainly composed of a conjugated diene compound. A resin composition comprising a hydrogenated block copolymer obtained by hydrogenation,
A resin composition, wherein the molecular weight distribution of the polypropylene resin in the resin composition is 8 or more. 2. The molecular weight distribution of the polypropylene resin in the resin composition is 9 or more.
3. The resin composition according to item 1. 3. Component (a) and component (b) in weight ratio of (a) /
(B) = 10/90 to 70/30, and (a) and (b)
The resin composition according to claim 1, wherein the component (c) is 3 to 40 parts by weight based on 100 parts by weight of the total of the components. 4. The resin composition according to claim 1, wherein the weight average molecular weight of (a) the polyphenylene ether resin is 10,000 or more. 5. A material for battery case parts comprising the resin composition according to claim 1. Description: