JP5078247B2 - Battery pack laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminate for a battery pack superior in extrusion lamination performance, metallic contact deterioration resistance, and surface appearance as a laminate for the battery pack in which a metal layer and a synthetic resin layer are laminated. <P>SOLUTION: The laminate for the battery pack has an inner synthetic resin layer 7 forming an inner surface which is constructed of a PP/PPE resin composition in which (A) polypropylene forming a continuous phase, (B) polyphenylene ether resin composition in which a free amine compound and an amine compound chemically bonded to polyphenylene ether are contained at 50 ppm or more in amino type total nitrogen, and which forms a dispersion phase, and (C) an additive, are melted and kneaded. The average distance between the particles of the dispersion phase in the PP/PPE resin composition is 10 &mu;m or less, and the melt viscosity ratio [(MFR value of adhesive layer resin component)/(MFR value of inner synthetic resin layer resin component)] is 0.2-5. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a constituent material of a battery pack in which an electrolyte, an electrode, and the like are housed in a flexible bag-shaped case, and in particular, a battery pack for a secondary battery such as a lithium ion secondary battery, a nickel-hydrogen battery, a lead storage battery, and an alkaline storage battery. It is related with the laminated body for battery packs suitable for the case.

  Conventionally, as a laminated body for battery packs, a flexible laminated body laminated in a three-layer structure of synthetic resin / metal / synthetic resin is known (for example, see Patent Document 1).

  In addition, in order to improve the heat resistance, rigidity, and impact resistance of polypropylene, PP / PPE resin composition containing polypropylene and polyphenylene ether is composed of copper (copper ion generation) that forms the continuous phase (matrix layer). This has been improved by contact with other transition metals (including compounds) (including transition metal ion generating compounds) for a long time, since these metals (metal ions) will deteriorate due to their catalytic action. PP / PPE resin compositions are known. It is also known that a PP / PPE resin composition with improved deterioration due to contact with a transition metal (metal contact deterioration) can be suitably used as a battery case material for a secondary battery. That is, a PP / PPE resin composition that can be suitably used as a battery case material for a secondary battery is obtained by oxidative polymerization using (a) 1 to 99% by weight of polypropylene and (b) a substituted alkylphenol as a monomer component. 99 to 1% by weight of a polyphenylene ether resin composition containing 50 ppm or more of total nitrogen of amino-type nitrogen composed of an amine compound chemically bonded to polyphenylene ether and a free amine compound not bonded to polyphenylene ether; ), PP / PPE resin compositions obtained by heating and kneading 1 to 100 parts by weight of the admixture with respect to 100 parts by weight of the total amount of the components (b) are known (for example, Patent Document 2). reference).

  However, in the present invention, extrusion laminate processability is not sufficient, and there is a problem that die line, thickness unevenness and swelling (waves) occur on the surface of the extruded laminate, and the quality of the laminate is significantly deteriorated. .

Japanese Patent Laid-Open No. 10-208720 Japanese Patent Laid-Open No. 10-110069

  Generally, transition metals such as copper, nickel, iron, lead, lithium, titanium, manganese, and zirconium are used as the metal of the electrode inside the battery. Therefore, the conventional PP / It is conceivable to extend the life of the battery pack by using the PPE resin composition as the synthetic resin layer of the battery pack laminate.

  However, the conventional PP / PPE resin composition with improved metal contact deterioration is mainly composed of a rigid box battery case, that is, injection molding, and is a laminate like a battery pack laminate. When it is used as a material of a laminate constituted by, that is, an extrusion laminate material, there is a problem that it is difficult to achieve both the extrusion laminate property and the metal contact deterioration resistance.

  The present invention has been made in view of the above-mentioned conventional problems, and in a laminate for a battery pack in which a metal layer and a synthetic resin layer are laminated, as a synthetic resin layer, a polypropylene that forms a continuous phase and a dispersed phase are formed. A battery that uses a PP / PPE resin composition obtained by melt-kneading a polyphenylene ether resin composition and an admixture, and that is compatible with extrusion laminating properties and metal contact deterioration resistance, and has an excellent surface appearance It aims at providing the laminated body for packs.

That is, the present invention
[1] In a battery pack laminate constituting a bag-shaped battery pack case in which a metal layer and a synthetic resin layer are laminated via an adhesive layer, the inner synthetic resin layer serving as the inner surface is (A) continuous. Polyphenylene ether resin composition 50 for forming a dispersed phase, containing 50 to 99% by weight of polypropylene for forming a phase, and (B) a free amine compound and an amine compound chemically bonded to polyphenylene ether in an amino-type total nitrogen of 50 ppm or more. And a PP / PPE resin composition obtained by melt-kneading 1 to 20 parts by weight of (C) admixture with respect to 100 parts by weight of the total amount of the above components (A) and (B). The average inter-particle distance of the dispersed phase in the PP / PPE resin composition is 10 μm or less, and the inner synthetic resin layer resin component and the adhesive layer resin component are melted. Degrees ratio [(adhesive layer MFR value of the resin component) / (MFR value of the inner synthetic resin layer resin component)] is laminate for battery pack, characterized in that from 1 to 4.4
[2] An inner synthetic resin layer is laminated on one side of the metal layer via an adhesive layer, and the adhesive layer is composed of a carboxylic acid, an acid anhydride group, a hydroxyl group, an amino group, an imide group, a glycidyl group, an oxazonyl group, It is composed of a modified polypropylene having one or more functional groups selected from mercapto groups and silyl groups, or a modified PP / PPE resin composition in which a part or all of the polypropylene of the PP / PPE resin composition is replaced with a modified polypropylene. The laminate for a battery pack according to [1], wherein
[3] The battery pack according to [1] or [2], wherein an outer synthetic resin layer serving as an outer surface of the battery pack is laminated on the other surface of the metal layer via an outer adhesive layer. Laminate,
[4] A battery pack using the battery pack laminate according to any one of [1] to [3],
It is.

  The present invention can provide a high-quality battery pack laminate that is excellent in metal contact resistance and appearance.

  Hereinafter, the present invention will be further described in detail.

  FIG. 1 is a perspective view illustrating an example of a battery pack, and FIG. 2 is a schematic cross-sectional view illustrating an example of a layer configuration of a battery pack laminate according to the present invention.

  As shown in FIG. 1, the battery pack 1 is one in which an electrolyte and electrodes (not shown) are accommodated in a flexible bag-like case 2, and the case 2 of this example is as shown in FIG. Two such laminates 3 are overlapped and fused around the circumference. In FIG. 1, reference numerals 4a and 4b denote extraction electrodes.

  The laminated body 3 of this example is provided on one side (the inner surface side of the case 2) of the metal layer 5 via an adhesive layer 6 (hereinafter, sometimes referred to as an inner adhesive layer in order to be distinguished from the outer adhesive layer). The inner synthetic resin layer 7 which is the surface is extruded and laminated, and the outer synthetic resin layer 9 which is the outer surface is extruded and laminated on the other surface of the metal layer 5 (the outer surface side of the case 2) via the outer adhesive layer 8. It has become.

  The metal layer 5 is selected from aluminum, iron, nickel, titanium, and alloys containing these metals as main components from the viewpoint of imparting pressure resistance during battery electrolyte foaming, metal extensibility, thermal conductivity, and cost. A metal foil or a metal plate can be used. Among these, aluminum is particularly suitable for battery pack applications because of its low specific gravity and excellent workability. The thickness of the metal layer 5 is preferably 1 to 500 μm, more preferably 1 to 100 μm, and particularly preferably 1 to 50 μm.

  At least the inner synthetic resin layer 7 of the laminate 3 is composed of (A) 50 to 99% by weight of polypropylene forming a continuous phase, and (B) a free amine compound and an amine compound chemically bonded to polyphenylene ether with amino-type total nitrogen. 50 to 1% by weight of a polyphenylene ether resin composition that forms a dispersed phase, containing 50 ppm or more, and 1 to 20 weights of (C) admixture with respect to 100 parts by weight of the total amount of the above components (A) and (B). The PP / PPE resin composition is obtained by melt-kneading the parts, and the average interparticle distance of the dispersed phase in the PP / PPE resin composition is 10 μm or less. The inner synthetic resin layer 7 is usually preferably 10 to 1000 μm thick, more preferably 10 to 500 μm, and still more preferably 10 to 100 μm.

  As the adhesive layer 6 interposed between the inner synthetic resin layer 7 and the metal layer 5 made of the PP / PPE resin composition, good adhesion to both the inner synthetic resin layer 7 and the metal layer 5 is achieved. However, a modified polypropylene or a modified PP / PPE resin composition can be used. The inner adhesive layer 6 is usually preferably 1 to 100 μm in thickness, more preferably 1 to 50 μm, and even more preferably 1 to 30 μm.

  The laminate 3 of the present invention uses the PP / PPE resin composition as the inner synthetic resin layer 6 that greatly affects the performance and life of the battery, and the PP / PPE resin composition as the outer synthetic resin layer 9. Synthetic resins other than those such as polypropylene resin, ABS resin, polyamide resin, and polyester resin can be used, and the material of the outer adhesive layer 8 can be freely selected according to the outer synthetic resin layer 9.

  Hereinafter, the components (A) to (C), the blending ratio of the components (A) to (C), the production method of the PP / PPE resin composition, the average interparticle distance of the dispersed phase and the adjustment method thereof, and the modified polypropylene Each will be explained.

[1] Component (A) A crystalline propylene homopolymer is used as the polypropylene as the component (A) in the present invention. Further, the crystalline propylene homopolymer portion obtained in the first step of polymerization, and propylene, ethylene and / or at least one other α-olefin (for example, butene-1, hexene-1, etc.) in the second and subsequent steps of polymerization. May be a crystalline propylene-ethylene block copolymer having a propylene-ethylene random copolymer portion obtained by copolymerization of a propylene-ethylene random copolymer, and a mixture of a crystalline propylene homopolymer and a crystalline propylene-ethylene block copolymer. It doesn't matter.

  In addition, the polypropylene used by this invention can be normally selected from the range whose melt flow rate (MFR: 230 degreeC and the load of 2.16Kg are based on ASTM D1238) 5-100g / 10min.

[2] Component (B) The polyphenylene ether resin composition of component (B) used in the present invention has a PP / PPE resin composition that has metal degradation resistance, heat resistance (load deflection temperature: DTUL), heat resistance creep resistance, It is an essential component for imparting flame retardancy, and an amine compound in which polyphenylene ether obtained by oxidative coupling polymerization using a substituted alkylphenol as a monomer component is chemically bonded to polyphenylene ether (the following formula (1) and formula ( 2) shows the bonding form, wherein formula (1) is a structure in which an aliphatic amine is chemically bonded to the benzyl position at the head end, and formula (2) is a structure in which the aliphatic amine is chemically bonded to the benzyl position in the main chain. And a polyphenol containing 50 ppm or more of total nitrogen of amino-type nitrogen comprising a free amine compound not bound to polyphenylene ether An enylene ether resin composition.

（上記式（１）および式（２）において、Ｒ¹およびＲ²はそれぞれ炭素数１〜２０のアルキル基または置換アルキル基、アリール基、置換アリール基を表し、Ｒ³は、水素、炭素数１〜４のアルキル基、またはアリール基を表す。）

(In the above formulas (1) and (2), R ¹ and R ² each represent an alkyl group having 1 to 20 carbon atoms, a substituted alkyl group, an aryl group, or a substituted aryl group, and R ³ represents hydrogen, 1 to 4 alkyl groups or aryl groups are represented.)

  The polyphenylene ether resin composition as component (B) comprises an amino acid comprising a polyphenylene ether to which an amine compound having at least one chemical structure selected from the above formulas (1) and (2) is bonded, and a free amine compound. The total nitrogen of the type nitrogen is 50 ppm or more, and the reduced viscosity (0.5 g / dl, chloroform solution, measured at 30 ° C.) is in the range of 0.15 to 0.70, more preferably 0.20 to 0.00. The composition of polyphenylene ether polymer and / or polyphenylene ether copolymer in the range of 60.

  Specific examples of the substituted alkylphenol monomer constituting the polyphenylene ether include 2,6-dimethylphenol, 2,3,6-trimethylphenol, 2-methyl-6-ethylphenol, and 2-methyl-6. -Phenylphenol etc. are mentioned, These monomers may be used independently and can also use together 2 or more types of different substituted alkylphenols.

  The method for producing such a polyphenylene ether resin composition is not particularly limited as long as a polyphenylene ether resin composition containing 50 ppm or more of total nitrogen of amino nitrogen composed of polyphenylene ether to which the amine compound is bonded and a free amine compound is obtained. However, it can be produced by, for example, oxidative coupling polymerization of the above-described phenol compound in the presence of a secondary amine compound. Known production methods include, for example, U.S. Pat. Nos. 3,306,874, 3,306,875, 3,914,266, and 4028341, JP-B-52-17880, JP-B-60-50373, and JP-A Examples thereof include methods described in JP-A-50-51197, JP-A-52-892, JP-A-63-152628, JP-A-8-157708, and the like.

  That is, the polyphenylene ether resin composition used in the present invention supplies the oxygen-containing gas while vigorously stirring by adding a catalyst and, if necessary, a co-catalyst to a solution containing the above phenol compound and secondary amine compound. Then, oxidative coupling polymerization is performed, and washing is performed in the polymer recovery step after the polymerization. At this time, amino group nitrogen composed of polyphenylene ether to which an amine compound is bonded and a free amine compound is contained in the entire recovered polymer. It can be obtained by preparing so as to contain 50 ppm or more of total nitrogen. As a catalyst used in the polymerization, all catalysts used for oxidative coupling polymerization of a copper-amine complex, a manganese-amine complex, a cobalt-amine complex, a manganese-alkoxide complex, and other known phenol compounds can be used.

  Examples of the secondary amine compound used in the polymerization include dimethylamine, diethylamine, di-n-propylamine, di-secondary-propylamine, di-n-butylamine, and di-secondary amine. -Butylamine, di-tertiary-butylamine, dipentylamine, dihexylamine, dinonylamine, didecylamine, diecosylamine, dibenzylamine, methylethylamine, methylbutylamine, methylcyclohexylamine, heptylcyclohexylamine, octadecylcyclohexylamine, etc., N -Phenylethanolamine, N- (m-methyl) phenylethanolamine, N- (P-methyl) phenylethanolamine, N- (2 ', 6'-dimethyl) phenylethanolamine, N- (2', 4 ' , 6'-trimethi ) Phenylethanolamine, N- (m-methoxy) phenylethanolamine, N- (P-chloro) phenylethanolamine, N- (m-chloro) phenylethanolamine, N- (o-chloro) phenylethanolamine, N -(O-ethyl) phenylethanolamine, N- (m-ethyl) phenylethanolamine, N- (p-ethyl) phenylethanolamine, N-methylaniline, N-ethylaniline, N-propylaniline, N -Butylaniline, N-methyl-2-methylaniline, N-methyl-2,6-dimethylaniline, N-methyl-2,4,6-trimethylaniline, N-naphthylaniline, diphenylaniline and the like.

  The polyphenylene ether resin composition used as the component (B) in the present invention, after the oxidative coupling polymerization using the above-described components, the polymerization solution is usually acids such as hydrochloric acid and acetic acid, EDTA (ethylenediaminetetratetraacetic acid), and Derivatives (including metal salts such as potassium) etc. are added to the polymerization solution to deactivate the catalyst, and then the resulting polymer is precipitated, washed with alcohols such as methanol, dried and recovered in powder form. can do. Furthermore, this powdery polyphenylene ether resin composition can be melt-kneaded with an extruder or the like to obtain pellets.

  The polyphenylene ether resin composition used as the component (B) in the present invention is a composition containing polyphenylene ether obtained by the above-described polymerization method and recovery method, but the amine compounds of the above formulas (1) and (2) In addition to the polyphenylene ether in which is chemically bonded, a tertiary aliphatic amine (for example, N, N, N ′, N′-tetramethyl) as a base used in the synthesis of the metal-amine complex of the polymerization catalyst described above Amine compounds remaining after polymerization of -1,3-diaminopropane, n-butyl-dimethylamine, etc., and secondary amine compounds added when synthesizing Formula (1) and Formula (2) during the polymerization process Free amine compound remaining after polymerization of EDTA (ethylenediaminetetra-ethylenediamine) used as a deactivator if necessary in the recovery and washing step after polymerization Prepared to contain 50 ppm or more, preferably 100 ppm or more, more preferably 300 to 10,000 ppm of total nitrogen of amino-type nitrogen composed of free amine compounds such as acetic acid) and derivatives thereof (including metal salts such as potassium). It has been done.

  In particular, the amino-type nitrogen content comprising the free amine compound remaining after the polymerization of the polyphenylene ether described above is the amount of secondary amine compound, tertiary aliphatic amine added in the polyphenylene ether polymerization, It can be controlled by adjusting the amount of the amino nitrogen compound composed of a free amine compound extracted in the washing step. And when the total nitrogen content of amino-type nitrogen is less than 50 ppm, the improvement effect of the metal deterioration resistance of the obtained PP / PPE resin composition cannot be obtained.

  As a method of knowing the total nitrogen content of amino nitrogen comprising an amine compound chemically bonded to polyphenylene ether and a free amine compound not bonded to polyphenylene ether contained in such a polyphenylene ether resin composition, for example, a trace nitrogen analyzer ( Using “TN-10” manufactured by Mitsubishi Chemical Corporation, measurement can be performed using a heating furnace temperature of 900 ° C., argon gas as a carrier gas, and oxygen gas as a combustion gas.

[3] Component (C) The admixture as the component (C) is obtained by heat-melting and kneading the polypropylene as the component (A) and the polyphenylene ether resin composition as the component (B), and continuously mixing the component (A). The phase is not particularly limited as long as it has the ability to stably disperse component (B) which is a dispersed phase.

  Examples of such admixtures include hydrogenated block copolymers, polypropylene-polystyrene graft (block) copolymers [block (graft) copolymers obtained by chemically bonding polypropylene molecular chains to polystyrene molecular chains], polypropylene. -Polyphenylene ether graft (block) copolymer [block (graft) copolymer obtained by chemically bonding a polypropylene molecular chain to a polyphenylene ether molecular chain], ethylene and α-olefin copolymer elastomer molecule in a polyphenylene ether molecular chain Block (graft) copolymer obtained by chemically bonding chains, block (graft) copolymer obtained by chemically bonding ethylene and α-olefin copolymer elastomer molecular chains to polystyrene molecular chains, etc. One or more of these Copolymers can be used as admixtures. Among these admixtures, the most preferred admixture is a hydrogenated block copolymer.

  The most preferred hydrogenated block copolymer as an admixture acts as a dispersing agent for dispersing the polyphenylene ether resin composition as the component (B) using the polypropylene as the component (A) as a continuous phase. Furthermore, the resulting PP / PPE resin composition is imparted with impact resistance, and the vinyl bond amount of the conjugated diene compound (total amount of 1,2-vinyl bond and 3,4-vinyl bond) is 30. 80% or more of a block copolymer consisting of at least one polymer block mainly comprising a conjugated diene compound of ~ 95% and at least one polymer block mainly comprising a vinyl aromatic compound is hydrogenated. This is a hydrogenated block copolymer.

  The number average molecular weight (Mn) of the hydrogenated block copolymer used in the present invention is preferably in the range of 5,000 to 1,000,000, more preferably in the range of 10,000 to 500,000. It is measured by a migration chromatography (GPC). The molecular structure of this block copolymer may be linear, branched, radial, or any combination thereof.

  The amount of styrene refers to the ratio of styrene blocks in the molecular chain of the hydrogenated block copolymer, and is preferably in the range of 20 to 90%, more preferably 30 to 80%. Usually, it can know by well-known methods, such as NMR method.

[4] Mixing ratio of components (A) to (C) In the present invention, 50 to 99% by weight of component (A) and 50 to 1% by weight of component (B) are combined so that the total amount is 100% by weight, Further, 1 to 20 parts by weight of component (C) is blended with respect to 100 parts by weight of the total amount of component (A) and component (B). If the amount of component (A) is too small and the amount of component (B) is too large, the required laminating properties cannot be obtained. Conversely, if the amount of component (A) is too large and the amount of component (B) is too small, sufficient metal contact deterioration resistance is prevented. Cannot be obtained. Moreover, when there are too many (C) components, required lamination property will not be acquired, and conversely, when there are too few (C) components, the distance between the particles of the disperse phase mentioned later becomes large, and sufficient metal contact-proof deterioration property is obtained. It can no longer be obtained.

  A preferable blending ratio of the component (A) and the component (B) is preferably 70 to 99% by weight of the component (A) and 30 to 30% of the component (B) because it is easy to obtain a superior laminating property and metal contact deterioration resistance. 1% by weight, more preferably 80 to 99% by weight of component (A) and 20 to 1% by weight of component (B), more preferably 85 to 99% by weight of component (A) and 15 to 1% by weight of component (B). It is a range.

  The amount of component (C) is preferably in the range of 1 to 12 parts by weight, more preferably 1 to 8 parts by weight, based on 100 parts by weight of the total amount of components (A) and (B).

[5] Method for Producing PP / PPE Resin Composition The PP / PPE resin composition used in the present invention is produced by melting and kneading the above-mentioned components (A) to (C) with a melt kneader in the above blending. can do. As the melt-kneader to be used, a multi-screw extruder having two or more screws capable of incorporating the kneading block at an arbitrary position of the screw is preferable, and the entire kneading block portion of the screw to be used is substantially (L / D ) ≧ 1.5, more preferably (L / D) ≧ 5 (where L is the total length of the kneading block, D is the maximum outer diameter of the kneading block), and (π · D · N / h) ≧ 50 (where π = 3.14, D = screw outer diameter corresponding to the metering zone, N = screw rotation speed (rotations / second), h = groove depth of the metering zone) It is preferable to satisfy the above).

  These extruders have at least a first raw material supply port on the upstream side with respect to the flow direction of the raw material, and at least a second raw material supply port on the downstream side. If necessary, one more downstream of the second raw material supply port. The above raw material supply ports may be provided, and a vacuum vent port may be provided between these raw material supply ports as necessary.

  When manufacturing the PP / PPE resin composition used in the present invention, the basic raw material supply method is that the total amount of the component (B) or the total amount of the component (B) and the total amount of the component (A) are supplied from the first raw material supply port. A part of the component (A) in a range not exceeding 50% is supplied together, and the whole amount of the component (A) or the remaining component (A) distributed to the first material supply port is supplied from the second material supply port. This is an extrusion method or a method in which the whole amount of the component (A) and the component (B) is supplied from the first raw material supply port.

  In addition, when hydrogenated block copolymerization is used as the component (C), a polymer block mainly composed of a conjugated diene compound in which the vinyl bond amount of the conjugated diene compound before hydrogenation is 55% or less is a conjugated diene compound. When the content of the hydrogenated block copolymer is 50% or more based on the total polymer block mainly comprising the above, it is optimal to supply the hydrogenated block copolymer by dividing it into a first raw material supply port and a second raw material supply port. When the polymer block mainly composed of a conjugated diene compound in which the vinyl bond amount of the conjugated diene compound before hydrogenation exceeds 55% has 50% or more with respect to all the polymer blocks mainly composed of the conjugated diene compound, this is required. The method of supplying the entire amount of the hydrogenated block copolymer to the first raw material supply port is optimal. When supplying the component (C) to the first raw material supply port, the component (B) or the component (B) and the component (A) are supplied together. Moreover, when supplying (C) component to a 1st raw material supply port, it is the method of supplying together with (A) component.

  Usually, the set temperature of the extruder barrel is 200 to 370 ° C, preferably 250 to 310 ° C.

  In addition, the PP / PPE resin composition used in the present invention includes, in addition to the above components (A) to (C), other additional components as necessary, for example, within a range that does not impair the characteristics and effects of the present invention. , Antioxidants, metal deactivators, flame retardants (organic phosphate compounds, ammonium polyphosphate flame retardants, aromatic halogen flame retardants, silicone flame retardants, etc.), fluorine polymers, plasticizers (low (Molecular weight polyethylene, epoxidized soybean oil, polyethylene glycol, fatty acid esters, etc.), flame retardant aids such as antimony trioxide, weathering (light) improvers, polyolefin nucleating agents, slip agents, inorganic or organic fillers And reinforcing materials (glass fiber, carbon fiber, polyacrylonitrile fiber, whisker, mica, talc, carbon black, titanium oxide, calcium carbonate, titanic acid Including additives such as various types of resin components such as polystyrene resin and polyethylene resin, and additives such as various colorants and mold release agents. .

[6] Average interparticle distance of dispersed phase and adjusting method thereof In the PP / PPE resin composition used in the present invention, the average interparticle distance of component (B) that is the dispersed phase needs to be 10 μm or less, Preferably, it is 8 μm or less and 1 μm or more. In the present invention, the blending amount of the component (B) is reduced in order to impart a good extrusion laminate property to the PP / PPE resin composition. The present invention has one feature in that it has been found that good metal contact deterioration resistance can be obtained with this small amount of component (B) by densely dispersing component (B). In addition, the average interparticle distance of a dispersed phase means the average value of the distance between the gravity centers between the particle | grains calculated | required with the measuring method mentioned later.

  In the PP / PPE resin composition used in the present invention, the average particle size of the dispersed phase is preferably 10 μm or less, more preferably 8 μm or less, and particularly preferably 5 μm or less. When the average particle diameter is too large, it becomes difficult to make the average interparticle distance 10 μm or less. It can be said that the average particle size is preferably as small as it is easy to reduce the average interparticle distance, but even if the average particle size is less than 0.1 μm, the improvement of the metal contact deterioration resistance is much improved only by labor. Therefore, the practical lower limit is 0.1 μm. In addition, an average particle diameter means the average value of the diameter of the said circle | round | yen when the circle | round | yen of each equal area calculated | required with the measuring method mentioned later is assumed.

  The adjustment of the average interparticle distance and the average particle diameter is performed by adjusting the blending ratio of the components (A) to (C) and the screw of the melt kneader (extruder) when the components (A) to (C) are melt-kneaded. The number of rotations and the shape and length of the kneading block can be used. The rotational speed of the screw is preferably 50 to 1000 rpm, more preferably 100 to 700 rpm, in order to reduce the average interparticle distance and the average particle diameter.

[7] Modified polypropylene The modified polypropylene and modified PP / PPE resin composition preferably used as the inner adhesive layer 6 in the present invention have an aliphatic unsaturated group, and further have a carboxylic acid group, an acid anhydride group, a hydroxyl group, A compound having one or more functional groups selected from amino group, imide group, glycidyl group, oxazonyl group, mercapto group and silyl group (hereinafter referred to as “functional compound”) is grafted or added to polypropylene. This is a resin obtained.

  In the modified polypropylene used in the present invention, the functional compound is preferably grafted or added in an amount of 0.01 to 10 parts by weight with respect to 100 parts by weight of the polypropylene. More preferably. In the modified PP / PPE resin composition, the functional compound is preferably grafted or added in an amount of 0.01 to 10 parts by weight with respect to 100 parts by weight of the PP / PPE resin composition. More preferably, it is grafted or added to ˜5 parts by weight.

  In the modified polypropylene, if the functional compound to be grafted or added is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, the unmodified polypropylene is replaced with the modified polypropylene. It may be a mixture. In the modified PP / PPE resin composition, the functional compound grafted or added is preferably 0.01 to 20 parts by weight, more preferably 0, relative to 100 parts by weight of the PP / PPE resin composition. It suffices if it is 1 to 8 parts by weight.

  Examples of functional compounds that chemically modify polypropylene include unsaturated dicarboxylic acids such as maleic acid, fumaric acid, chloromaleic acid, citraconic acid, itaconic acid, and hymic acid, acrylic acid, methacrylic acid, crotonic acid, and vinyl acetic acid. , Unsaturated monocarboxylic acids such as pentenoic acid, linoleic acid and cinnamic acid, and acid anhydrides of α, β-unsaturated dicarboxylic acids such as maleic anhydride, acrylic anhydride and hymic anhydride, and α, β -Acid anhydrides of unsaturated carboxylic acids, unsaturated alcohol compounds such as allyl alcohol, 3-buten-2-ol, propargyl alcohol, alkenyl phenols such as p-vinylphenol and 2-propenylphenol, p- Aminostyrene is mentioned.

  Also, unsaturated amine compounds such as allylamine and N-vinylaniline, imides of α, β-unsaturated dicarboxylic acids or α, β-unsaturated monocarboxylic acids such as maleimide, glycidyl acrylate, glycidyl methacrylate, allyl Unsaturated glycidyl compounds such as glycidyl, unsaturated oxazoline compounds such as isopropenyl oxazoline, unsaturated mercapto compounds such as p-tert-butylmercaptomethylstyrene, 2- (3-cyclohexenyl) ethyltrimethoxysilane, 1 , 3-divinyltetraethoxysilane, vinyltris- (2-methoxyethoxy) silane, and unsaturated organosilane compounds such as 5- (bicycloheptenyl) triethoxysilane, among which maleic anhydride is the most functional compound. Preferred.

  These functional compounds can be used alone or in combination with a vinyl aromatic compound such as styrene copolymerizable with the functional compound. Examples of the radical generator that can be used in the modification include dicumyl peroxide, di-tert-butyl peroxide, tert-butylcumyl peroxide, 2,5-dimethyl-2,5-di ( tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3, n-butyl-4,4-bis (tert-butylperoxy) valerate, 1, 1-bis (tert-butylperoxy) 3,3,5-trimethylcyclohexane and the like can be mentioned, and one or more can be suitably selected from these.

  The amount of the functional compound added to the modified polypropylene can be usually known by a known method such as NMR, FTIR, or titration.

[8] Modified polypropylene / PPE
Using the modified polypropylene, PPE resin and admixture, it can be obtained as pellets in the same manner as in “[5] Method for producing PP / PPE resin composition”.

[9] Viscosity ratio The difference in melt viscosity between the resin composition forming the inner synthetic resin layer and the resin forming the adhesive layer is that the flow rate difference and melt viscosity difference of each layer are large in the die during coextrusion lamination. Then, a flow mark is generated. This phenomenon is likely to occur particularly in the feed block system widely used as a multilayer die. Therefore, it is desirable that the difference in melt viscosity between the resin composition forming the inner synthetic resin layer and the resin forming the adhesive layer is small, and the resin composition and adhesive layer forming the inner synthetic resin layer are The melt viscosity ratio [(MFR value of the adhesive layer resin component) / inner (MFR value of the side synthetic resin layer resin component)] to the resin to be formed is 1 to 4.4 .

  Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples.

  The materials used in the examples and comparative examples will be described.

[I] Polypropylene: Component (A) Polypropylene homopolymer resin (density: 0.91, MFR: 8 g / 10 min, melting point: 165 ° C.) was used. Let this polypropylene be (A-1).
Polypropylene homopolymer resin (density: 0.91, MFR: 0.5 g / 10 min, melting point: 168 ° C.) was used. Let this polypropylene be (A-2).

[B] Polyphenylene ether resin composition: component (B) The polyphenylene ether resin composition was produced by carrying out polymerization using a continuous polymerization reactor consisting of three complete mixing tanks.

  The first reactor has a capacity of 1.5 liters and is equipped with a circulation pump, and the second and third reactors have stirrers with capacities of 3.7 liters and 1.5 liters, respectively. It was.

  The catalyst solution was obtained by dissolving cuprous oxide in 35% hydrochloric acid, adding methanol, and further adding di-n-butylamine, N, N, N ′, N′-tetramethyl-1,3-diaminopropane and methanol. It was adjusted. The monomer solution was prepared by dissolving 2,6-dimethylphenol in mixed xylene and n-butanol.

  The catalyst solution and the monomer solution were fed to the first reactor at a constant rate. The composition of the reaction raw material liquid obtained by combining the catalyst solution and the monomer solution is as follows.

  The 2,6-dimethylphenol concentration is 20% by weight, and the weight ratio of the solvent used is mixed xylene: n-butanol: methanol = 60: 20: 20. Per 100 moles of 2,6-dimethylphenol, copper is 0.03 mole, chlorine (Cl) ion is 0.276 mole, di-n-butylamine is 1.1 mole, N, N, N ′, N′-tetra Methyl-1,3-diaminopropane was in a proportion of 2.7 mol. In addition, 2,6-dimethylphenol was supplied at a rate of 210 g / Hr.

  In the first reactor, oxygen gas was allowed to flow while vigorously circulating the reaction solution with a circulation pump. The internal temperature was controlled to 38 ° C.

  The reaction solution sent from the first reactor to the second reactor at the head pressure was uniform. The temperature of the second reactor is controlled at 35 ° C., oxygen gas is supplied at 500 ml / min, and when the polymerization proceeds further, a polymer is precipitated in the system, but is dispersed as a slurry throughout the reactor by stirring. did.

  The slurry-like reaction liquid containing the polymer particles that entered the third reactor by overflow from the second reactor was temperature-controlled at 40 ° C. while stirring with a stirrer in the third reactor, and oxygen gas was 250 ml / min. Supplied with. The slurry-like reaction liquid overflowing from the third reactor was continuously taken out.

  Dilute hydrochloric acid and methanol were added to the slurry-like yellowish white reaction solution, filtered, and dried to obtain a polyphenylene ale resin composition (B-1). The polyphenylene ether resin composition (B-1) obtained here was purified and washed with a mixed solvent (mixed xylene / butanol / methanol = 1/1/2) and dilute hydrochloric acid, and dried to obtain a polyphenylene ether resin composition (B -2) was obtained. The polyphenylene ether resin composition (B-2) obtained here was dissolved in toluene, further purified and washed with methanol, and further dried to obtain a polyphenylene ether resin composition (B-3).

  Furthermore, the polyphenylene ether resin composition (B-3) obtained here was dissolved in toluene, further purified and washed with methanol, and further dried to obtain a polyphenylene ether resin composition (B-4). Further, the polyphenylene ether resin composition (B-4) obtained here was dissolved in toluene, purified and washed again with methanol, and further dried to obtain a polyphenylene ether resin composition (B-5).

The amine compound chemically bonded to the polyphenylene ether in the polyphenylene ether resin composition (B-1) obtained by oxidative polymerization was confirmed on the ¹ H nuclear magnetic resonance spectrum. A methylene group signal was observed at 3.63 ppm, and four types of n-butyl group signals corresponding to R ¹ and R ² were observed at 2.47 ppm, 1.50 ppm, 1.29 ppm, and 0.88 ppm. Also from the area intensity ratio, it was consistent with the structural formula represented by the formula (1).

Furthermore, the structural formula represented by the above formula (2) in which an aliphatic secondary amine is bonded to the benzyl position in the main chain is a ¹ H nuclear magnetic resonance which is very similar to the structure of the structural formula represented by the above formula (1). Although the spectrum is given, each signal is clearly distinguishable from the signal of the structural formula shown in the above formula (1), the signal of the methylene group is observed at 3.36 ppm, and two signals at the end of the n-butyl group Were observed at 1.17 ppm and 0.80 ppm. From the ¹ H nuclear magnetic resonance spectrum, it was confirmed that an amine compound chemically bonded to polyphenylene ether was present in the polyphenylene ether resin composition.

  Next, in order to confirm the total nitrogen content of the amino nitrogen composed of an amine compound chemically bonded to the polyphenylene ether and a free amine compound not bonded to the polyphenylene ether contained in the polyphenylene ether resin composition, a trace nitrogen analyzer (“TN-10” manufactured by Mitsubishi Chemical Corporation), using a furnace temperature of 900 ° C., argon gas as a carrier gas, and oxygen gas as a combustion gas, all contained in the polyphenylene ether resin composition obtained above When the nitrogen content was measured, the polyphenylene ether resin composition (B-1) was 2200 ppm, the polyphenylene ether resin composition (B-2) was 600 ppm, the polyphenylene ether resin composition (B-3) was 210 ppm, and the polyphenylene ether resin. Composition (B-4) is 60 ppm Polyphenylene ether resin composition (B-5) was 30 ppm.

[C] Admixture: Component (C) A hydrogenated styrene-butadiene copolymer (molecular weight (Mn): 85,000, bound styrene content: 60%) was used. From one polymer block made of butadiene and one polymer block made of styrene having a vinyl bond amount (total amount of 1,2-vinyl bond and 3,4-vinyl bond) of 65% This is a hydrogenated block copolymer obtained by hydrogenating 85% of the block copolymer.

[D] Modified polypropylene: adhesive layer The above polypropylenes (A-1) and (A-2) were subjected to a twin screw extruder (“ZSK-25” manufactured by WERNER & PFLIDEERER, Germany) at 280 ° C. and a screw rotation speed of 300 rpm. At the time of melt kneading, 1 part by weight of maleic anhydride was added to produce (modified A-1) and (modified A-2) modified polypropylene resin pellets.

  In addition, due to the end group modification treatment in the adhesive layer resin, when the maleic anhydride is added to the PP resin and extruded while heating and melting, the phenomenon that the MFR value increases due to the decrease in molecular weight (modified A-1) and As seen in (Modified A-2), the increase in MFR value of (Modified A-2) having a particularly high molecular weight tended to be remarkable.

[E] Modified PP / PPE resin: adhesive layer The above-mentioned modified polypropylene (modified A-1), PPE resin (B-3) and admixture in the composition ratios shown in Table 4 and the PP / PPE resin composition described later. The same process as the manufacturing method of the product, that is, twin-screw extrusion having a first raw material supply port and a second raw material supply port (located substantially at the center of the extruder) set at a temperature of 250 to 320 ° C. and a screw rotation speed of 300 rpm It was melt-kneaded using a machine ("ZSK-40" manufactured by WERNER & PFLIDELER, Germany) to obtain pellets.

<Evaluation of extrusion laminate properties>
The surface condition of the extruded laminate was evaluated by visually observing the occurrence of defective appearance (die line, thickness unevenness, swelling (wave), flow mark), and evaluated by the following evaluation method.

A: Always good,
○: No noticeable appearance defect occurred Δ: Noticeable appearance defect occurred x: Extrusion laminating property was evaluated based on an evaluation criterion that a very noticeable appearance defect occurred.

<Metal degradation resistance evaluation>
A copper foil was brought into close contact with the surface of the inner synthetic resin layer of the laminate, and was further sandwiched between two 2 mm aluminum plates and fixed with clips. The metal contact deterioration is promoted by heat exposure in a gear-oven at 150 ° C., and the surface state of the inner synthetic resin layer is observed with a magnifying glass approximately 10 times every 100 hours until a crack due to metal contact deterioration occurs. Was observed and recorded for up to 2000 hours.

<Measurement of melt viscosity>
The MFR (melt flow rate) of the pellets of the resin composition of the inner synthetic resin layer and the adhesive layer was measured under the conditions of temperature: 230 ° C. and load: 0.22 N in accordance with ASTM D1238.

<Melting viscosity ratio>
Let the melt viscosity ratio of each resin component which comprises an inner side synthetic resin layer and an adhesive layer be the value calculated | required from the following formula.
Melt viscosity ratio = (MFR value of adhesive layer resin component) / (MFR value of inner synthetic resin layer resin component)

<Measurement of average interparticle distance>
The average interparticle distance in the present invention can be measured as follows. The cross-sectional morphology perpendicular to the flow direction of the PP / PPE resin composition, which is an extrusion-laminated inner synthetic resin, is photographed with a 35 mm negative film at a magnification of 10,000 times, taken into a computer with a film scanner, and an image processing program ( Using the “LUZEX AP” manufactured by Nireco Corporation, the average interparticle distance was measured by measuring the interparticle distance using the distance between the adjacent centroids of the measurement parameters, and calculating the average interparticle distance. This can be done by determining the equivalent circle diameter of the particle and the distance between the centroids of adjacent particles.

<Examples of production of laminates of Examples and Comparative Examples>
Each component of the inner synthetic resin layers of Examples 1 to 11 and Comparative Examples 1 to 9 shown in Tables 1 to 4 is set to a temperature of 250 to 320 ° C. and a screw rotation speed of 300 rpm, and the first raw material supply port and the second Using a twin-screw extruder (“ZSK-40” manufactured by WERNER & PFLIDEERER, Germany) having a raw material supply port (located almost at the center of the extruder), the component (A) is half of the composition ratio of PP resin (B) component: PPE resin and (C) component: the total amount of the composition ratio of the admixture is supplied to the first raw material supply port, and the remaining half of the (A) component: PP resin composition ratio is the second raw material. It supplied to the supply port and melt-kneaded and obtained as a pellet.

  The composition pellet as the inner synthetic resin layer is introduced into one cylinder of the two extruders, and the modified polypropylene as the adhesive layer is introduced into the other cylinder, each extruded at 280 ° C., and a feed block system having a width of 400 mm Extruded from the T-die and co-extrusion laminated to form a laminate of the inner synthetic resin layer of PP / PPE resin composition (thickness after film formation is 50 μm) and adhesive layer (thickness after film formation is 10 μm), The adhesive layer surface of the laminate was pressure-bonded with a degreased metal layer having a thickness of 50 μm and cooled to obtain a laminate (laminate) composed of three layers, a metal layer, an adhesive layer, and an inner synthetic resin layer. . In an actual battery pack, a synthetic resin layer is provided on both sides of the metal layer, but for simplification of the test, only one side is laminated.

  Aluminum foil was used as the metal layer.

  The extrusion laminate property was evaluated based on the obtained laminate.

[Examples 1 to 4 and Comparative Examples 1 to 5]
In the composition of the inner synthetic resin layer, PP resin (A-1) or PP resin (A-1) and PPE resin (B-3) having the composition shown in Table 1 are blended to make a total of 100 parts by weight, and further, an admixture The MFR of the pellet obtained by adding was measured. Further, using the modified PP (modified A-1) or (modified A-2) for the adhesive layer, the laminate property of the inner synthetic resin layer of the laminate obtained by extrusion lamination, the inter-particle distance, the crack generation time (metal resistance) Degradability) was measured, and the results are shown in Table 1.

[Examples 5-7 and Comparative Examples 6-8]
In the composition of the inner synthetic resin layer, the PP resin (A-1) and the PPE resin (B-3) are blended so that the total amount becomes 100 parts by weight as shown in Table 2, and 10 parts by weight of an admixture is added. The MFR of the obtained pellet was measured. Furthermore, using the modified PP (modified A-1) for the adhesive layer, the laminate property and interparticle distance of the inner synthetic resin layer of the laminate obtained by extrusion lamination, the crack generation time (metal degradation resistance) were measured, The results are shown in Table 2. Examples 2 and 4 are also shown in Table 2 for comparison.

[Examples 8 to 10 and Comparative Example 9]
In the composition of the inner synthetic resin layer, the composition shown in Table 3 so that PP resin (A-1) and PPE resins (B-1) to (B-5) having different amino-type total nitrogen amounts are 100 parts by weight in total. The MFR of the pellets obtained by blending at a ratio and adding the admixture was measured. Further, the adhesive layer was modified with PP (modified A-1) and (modified A-2), the laminate property of the inner synthetic resin layer of the laminate obtained by extrusion lamination, the distance between particles, the crack generation time (metal resistance) Table 3 shows the results of the measurement of deterioration. Example 1 is also shown for comparison.

[Example 11]
Using the modified PP / PPE resin obtained by blending as shown in Table 4 as the adhesive layer constituting resin, an aluminum foil was used as the metal layer to prepare a laminate, and the following peel strength test was performed. The inner synthetic resin layer and the adhesive layer of the laminate are cut into a 30-mm width tanger shape with a sharp razor, and one end of the aluminum and the adhesive layer are peeled off by hand. As shown in FIG. 3, the strip-shaped resin layer and aluminum were each fixed to the chuck of a tensile tester, and the peel strength was measured at a tensile speed of 3 mm / min. Since the adhesive strength exceeded the strength of the resin layer and the resin layer was broken, the maximum value at that time was measured.

  The laminate obtained in Example 1 was also subjected to a peel strength test in the same manner as in Example 11, and the results are also shown in Table 4.

Incidentally, definitive in Tables 1 to 4 (A-1) ~ ( A-2), (B-1) ~ (B-5), the numerical column (modified A-1) ~ (modified A-2) The unit of the numerical value in the column of the admixture is parts by weight relative to 100 parts by weight of the total amount of (A-1) to (A-2) and (B-1) to (B-5).

It is a perspective view which shows an example of a battery pack. It is a cross-sectional schematic diagram which shows an example of the layer structure of the laminated body for battery packs which concerns on this invention. It is explanatory drawing of a peeling strength test.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery pack 2 Case 3 Laminated body 4a Lead electrode 4b Lead electrode 5 Metal layer 6 Adhesive layer (inner side)
7 inner synthetic resin layer 8 outer adhesive layer 9 outer synthetic resin layer

Claims (4)

In the battery pack laminate that forms the bag-shaped battery pack case in which the metal layer and the synthetic resin layer are laminated via the adhesive layer, the inner synthetic resin layer that forms the inner surface forms the continuous phase (A) 50 to 99% by weight of polypropylene, and (B) a polyphenylene ether resin composition for forming a dispersed phase containing 50 ppm or more of amine compound chemically bonded to a free amine compound and polyphenylene ether in amino-type total nitrogen. %, And a PP / PPE resin composition obtained by melt-kneading 1 to 20 parts by weight of (C) admixture with respect to 100 parts by weight of the total amount of the above components (A) and (B). The average inter-particle distance of the dispersed phase in the PP / PPE resin composition is 10 μm or less, and the melt viscosity ratio between the inner synthetic resin layer resin component and the adhesive layer resin component (Adhesive layer MFR value of the resin component) / (MFR value of the inner synthetic resin layer resin component)] is the battery pack stack, characterized in that from 1 to 4.4.
  An inner synthetic resin layer is laminated on one side of the metal layer via an adhesive layer, and the adhesive layer comprises a carboxylic acid, an acid anhydride group, a hydroxyl group, an amino group, an imide group, a glycidyl group, an oxazonyl group, a mercapto group, and It is composed of a modified polypropylene having one or more functional groups selected from silyl groups or a modified PP / PPE resin composition in which a part or all of the polypropylene of the PP / PPE resin composition is replaced with a modified polypropylene. The laminated body for battery packs of Claim 1 characterized by these.   The battery pack laminate according to claim 1 or 2, wherein an outer synthetic resin layer serving as an outer surface of the battery pack is laminated on the other surface of the metal layer via an outer adhesive layer.   The battery pack which uses the laminated body for battery packs of any one of Claims 1-3.

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