Rubber composition, and battery

Abstract

The invention provides a rubber composition which can extinguish fire in a short time in the event of a sharp temperature rise of a battery cell and the like, and which is excellent in adhesion, workability, and followability to a protected object. According to the invention, there is provided a rubber composition which contains 50 to 2,000 parts by mass of a metal hydroxide with respect to 100 parts by mass of a base polymer containing a liquid rubber and a solid elastomer, and the mass ratio of the liquid rubber to the solid elastomer is 95:5 to 50:50.

Description

Technical Field

[0001] This invention relates to a rubber composition and a battery. More particularly, it relates to a putty-like rubber composition primarily used in battery applications. Background Technology

[0002] Lithium-ion batteries and other types of batteries sometimes experience thermal runaway due to internal short circuits, leading to fires or smoke. To mitigate these problems caused by thermal runaway, researchers have attempted to use protective materials such as fire-resistant materials or heat-insulating layers around the battery cells. The aim of these protective materials is to prevent the heat from the already hot battery cells from being conducted to other battery cells and the casing housing the battery cells.

[0003] For example, Patent Document 1 discloses a refractory resin composition containing an endothermic agent with a thermal decomposition start temperature of 800°C or less and an endothermic heat of 300 J / g or more, and a resin.

[0004] [Existing Technical Documents]

[0005] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-143139 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] Patent Document 1 describes a refractory resin composition that, for example, incorporates a large amount of aluminum hydroxide into EVA resin, enabling it to extinguish fires in a short time when batteries, such as those in mobile phones, catch fire. However, the large amount of inorganic compounds incorporated into the resin impairs its flexibility or adhesiveness, preventing it from fully conforming to the cylindrical battery cell and leaving gaps that could allow the fire to spread to the outside.

[0009] Therefore, the present invention provides a rubber composition that can extinguish fires caused by rapid temperature rises in battery cells in a short time, and has excellent adhesion, workability, and conformability to the protected object.

[0010] Solution for solving the problem

[0011] [Technical solution used to solve the problem]

[0012] The inventors have conducted diligent research to solve the aforementioned problems. As a result, they discovered that by using a composition with a specific composition, the aforementioned problems can be solved, thus completing the present invention.

[0013] That is, according to the present invention, the following invention is provided.

[0014] [1] A rubber composition comprising, for every 100 parts by weight of a base polymer, 50 to 2000 parts by weight of a metal hydroxide.

[0015] The matrix polymer comprises liquid rubber and solid elastomer, and the mass ratio of the liquid rubber to the solid elastomer is 95:5 to 50:50.

[0016] [2] The rubber composition as described in [1], wherein the metal hydroxide comprises aluminum hydroxide.

[0017] [3] The rubber composition described in [1] or [2] is putty.

[0018] [4] The rubber composition described in any of [1] to [3] is used in a battery.

[0019] [5] A battery comprising a component made of a rubber composition described in any one of [1] to [4].

[0020] The effects of the invention

[0021] According to the present invention, a rubber composition can be provided that can extinguish fires that occur in a short time due to rapid temperature rise in batteries, and has excellent adhesion, workability, and conformability to the protected object. This rubber composition, for example, has suitable softness, and therefore can be used as a putty-like protective material that can also conform to the shape of cylindrical battery cells. Attached Figure Description

[0022] Figure 1 middle, Figure 1 A is a schematic diagram showing a rubber composition disposed on the surface of a cylindrical battery cell. Figure 1 B is a schematic diagram showing a state in which a rubber composition is disposed on the surface of a cylindrical battery cell.

[0023] Figure 2 This is a schematic diagram illustrating the adhesion test. Detailed Implementation

[0024] The following describes in detail the method for carrying out the present invention (hereinafter referred to as "this embodiment"), but the present invention is not limited thereto, and various changes can be made without departing from its spirit. This rubber composition is a composition with excellent deformability and can be used as a putty that is easy to conform to shapes. That is, the composition can also be provided in the form of a putty-like refractory composition.

[0025] The rubber composition of this embodiment comprises a matrix polymer and a metal hydroxide. The matrix polymer comprises a liquid rubber and a solid elastomer, and the mass ratio of the liquid rubber to the solid elastomer is 95:5 to 50:50. The components will be described below.

[0026] 1. Matrix polymer

[0027] The matrix polymer comprises a liquid rubber and a solid elastomer, and the mass ratio of the liquid rubber to the solid elastomer is 95:5 to 50:50. This mass ratio is preferably 93:7 to 60:40, and more preferably 90:10 to 70:30. If the proportion of liquid rubber is too high, workability deteriorates; if the proportion of liquid rubber is too low, followability deteriorates. If the total mass ratio of the liquid rubber and the solid elastomer is set to 100, the mass ratio of the solid elastomer can be, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50, or any value between any two of the values ​​exemplified here. The mass ratio of the liquid rubber is the value obtained by subtracting the mass ratio of the solid elastomer from 100.

[0028] The rubber composition contains, for example, 5 to 70% by mass of a matrix polymer in 100% by mass of the rubber composition, preferably 6 to 25% by mass of a matrix polymer, and more preferably 7 to 15% by mass of a matrix polymer.

[0029] Liquid rubber

[0030] In this invention, the liquid rubber can be any substance as long as it is a rubber that is fluid at room temperature (25°C), such as liquid polyisoprene, liquid polybutadiene, liquid polychloroprene, liquid polybutene, liquid butyl rubber, etc., but it is not necessarily limited to one type, and two or more types can be mixed. The liquid rubber is preferably liquid polyisoprene or liquid polybutene, and more preferably liquid polyisoprene.

[0031] Solid Elastomers

[0032] In this invention, the solid elastomer can be any substance as long as it is a solid elastomer at room temperature (25°C). Examples include: natural rubber, isoprene rubber, butadiene rubber, 1,2-polybutadiene rubber, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, butyl rubber, chlorinated butyl rubber, chlorinated polyethylene rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber (EPDM), ethylene-vinyl acetate rubber, chloroprene rubber, chlorosulfonated polyethylene, acrylic rubber, epichlorohydrin rubber, acrylonitrile-butadiene rubber (NBR), reclaimed rubber, and other crosslinkable rubbers, fluororubber, polyurethane rubber, styrene-based thermoplastic elastomers, etc., but it is not necessarily limited to one type, and two or more types can be mixed.

[0033] Styrene-based thermoplastic elastomers are thermoplastic elastomers containing monomer units derived from vinyl aromatic hydrocarbons. Thermoplastic elastomers are elastomers that soften upon heating and exhibit flowability, unlike rubber which lacks this property. Styrene-based thermoplastic elastomers are preferably block copolymers composed of polymer blocks primarily composed of vinyl aromatic hydrocarbons and polymer blocks primarily composed of conjugated dienes. Examples of vinyl aromatic hydrocarbons include styrene, p-methylstyrene, α-methylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, and monobromostyrene; these can be used alone or in combination of two or more. Examples of conjugated dienes include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene; these can be used alone or in combination of two or more.

[0034] Specific examples of styrene-based thermoplastic elastomers include: styrene-butadiene-styrene (SBS) copolymer, styrene-isoprene-styrene (SIS) copolymer, styrene-ethylene-butene-styrene (SEBS) copolymer, styrene-isoprene-hydrogenated styrene-isoprene-styrene (SEPS) copolymer, styrene-ethylene-propylene (SEP) copolymer, styrene-ethylene-propylene-styrene (SEPS) copolymer, and styrene-ethylene-ethylene-propylene-styrene (SEEPS) copolymer.

[0035] The solid elastomer is preferably rubber (rubber-like), wherein butyl rubber, EPDM, or NBR is preferred, and butyl rubber is particularly preferred.

[0036] The matrix polymer may consist solely of liquid rubber and solid elastomer, or it may contain other polymers. Examples of other polymers include resins that are neither liquid rubber nor solid elastomers (such as polyolefins and polystyrene). Regarding the matrix polymer, it comprises at least 50% by mass of liquid rubber and solid elastomer in 100% by mass, preferably at least 80% by mass, more preferably at least 95% by mass, and even more preferably (substantially) 100% by mass of liquid rubber and solid elastomer.

[0037] 2. Metal hydroxides

[0038] Examples of metal hydroxides include aluminum hydroxide, calcium hydroxide, and magnesium hydroxide, but are not necessarily limited to one type; a mixture of two or more types may also be used. Aluminum hydroxide or calcium hydroxide is preferred, with aluminum hydroxide being particularly preferred.

[0039] The content of metal hydroxide relative to 100 parts by weight of the matrix polymer is 50 to 2000 parts by weight, preferably 250 to 2000 parts by weight, more preferably 250 to 1600 parts by weight, and even more preferably 480 to 1200 parts by weight. If the content of metal hydroxide is 50 parts by weight or more, the fire extinguishing properties are good. If the content of metal hydroxide is 2000 parts by weight or less, the flexibility, conformability, or adhesion are good. The content of metal hydroxide relative to 100 parts by mass of the matrix polymer is, for example, 50, 100, 150, 200, 250, 300, 350, 400, 450, 480, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, or 2000 parts by mass, or may be within any two of the values ​​exemplified herein.

[0040] 3. Other ingredients

[0041] In this embodiment, without compromising its effectiveness, inorganic compounds other than metal hydroxides, fibrous organic compounds, plasticizers (softeners), anti-aging agents, processing aids, lubricants, flame retardants, tackifiers, etc., commonly used in rubber formulations may also be used.

[0042] <Inorganic compounds other than metal hydroxides>

[0043] Inorganic compounds other than metal hydroxides include, for example: metal oxides such as aluminum oxide, aluminosilicates, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, and ferrites; montmorillonite-based clays such as sepiolite, bentonite, montmorillonite, and hectorite; fibrous clays such as palygorskite; sericite, illite, glauconite, chlorite, talc, zeolite, aluminum bentonite, chlorite, soapstone, hectorite, zinc bentonite, stevensite, cristobalite, bentonite, kaolin, and hydrotalcite; and metals such as basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, strontium carbonate, and barium carbonate. Carbonates; glass fibers (E, C, S, D), rock wool, ceramic fibers (silica-alumina fibers, alumina fibers, silica fibers), zirconium oxide fibers, carbon fibers, blocky alkaline earth silicate fibers, gypsum fibers, carbon fibers, metal fibers, slag fibers, basalt fibers, and other fibrous inorganic compounds; calcium salts such as calcium sulfate and calcium silicate, glass beads, silica-based hollow spheres, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon balls, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum borate, molybdenum sulfide, silicon carbide, zinc borate, various magnetic powders, fly ash, inorganic hollow fillers, perlite, obsidian, spherical, resinstone, diatomaceous earth, dewatered sludge, boron, sodium tetraborate hydrate (borax), silica, vermiculite, thermally expandable graphite, inorganic phosphate compounds, etc. These inorganic compounds can be used alone or in combination of two or more.

[0044] The content of inorganic compounds other than metal hydroxides relative to 100 parts by mass of the matrix polymer is, for example, less than 100 parts by mass, preferably 0.1 to 100 parts by mass. Specifically, the content of inorganic compounds other than metal hydroxides relative to 100 parts by mass of the matrix polymer is, for example, 0, 0.1, 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 parts by mass, or may be within any two of the values ​​exemplified herein.

[0045] Thermally Expanding Graphite

[0046] The rubber composition of the present invention may contain thermally expandable graphite. When thermally expandable graphite is contained, the graphite expands upon heating, thereby forming a large volume of voids, which function as a flame retardant and thus inhibit the spread of fire.

[0047] Thermally expandable graphite refers to graphite with the following property: when exposed to a temperature above the expansion initiation temperature (around 200°C) under normal pressure, it expands to more than 100 times its original size.

[0048] There are no particular limitations on this type of graphite. For example, it can be a crystalline compound that maintains the layered structure of graphite by surface treatment of graphite powders such as natural graphite and thermally decomposed graphite using inorganic acids such as sulfuric acid or nitric acid, and strong oxidizing agents such as concentrated nitric acid or permanganate. It should be noted that graphite powders such as natural graphite and thermally decomposed graphite can also be powders that have undergone deacidification treatment or further neutralization treatment.

[0049] The content of thermally expandable graphite relative to 100 parts by weight of the matrix polymer is, for example, 300 parts by weight or less, preferably 1 to 300 parts by weight, more preferably 20 to 200 parts by weight, and even more preferably 30 to 150 parts by weight. When the content of thermally expandable graphite is within the above range, large-volume voids are easily formed in the rubber composition, thus improving flame retardancy.

[0050] <Inorganic Phosphoric Acid Compounds>

[0051] Inorganic phosphoric acid compounds refer to compounds that contain at least one of the following: phosphoric acid compounds, phosphite compounds, hypophosphite compounds, metaphosphite compounds, pyrophosphite compounds, and polyphosphite compounds.

[0052] As a phosphoric acid compound, there are no particular limitations. Examples include: aluminum dihydrogen phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, calcium dihydrogen phosphate, zinc dihydrogen phosphate, aluminum hydrogen phosphate, sodium hydrogen phosphate, potassium hydrogen phosphate, calcium hydrogen phosphate, zinc hydrogen phosphate, trialuminum phosphate, trisodium phosphate, tripotassium phosphate, tricalcium phosphate, trizinc phosphate, trimagnesium phosphate, monoammonium phosphate, diammonium phosphate, tricalcium phosphate, aluminum phosphate, etc.

[0053] Examples of phosphorous compounds include: aluminum phosphite, aluminum hydrogen phosphite, sodium phosphite, potassium phosphite, calcium phosphite, and zinc phosphite.

[0054] Examples of hypophosphite compounds include aluminum hypophosphite, sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, and zinc hypophosphite.

[0055] Examples of metaphosphate compounds include: aluminum metaphosphate, sodium metaphosphate, potassium metaphosphate, calcium metaphosphate, zinc metaphosphate, and sodium hexametaphosphate.

[0056] Examples of pyrophosphate compounds include sodium pyrophosphate.

[0057] Examples of polyphosphate compounds include ammonium polyphosphate, sodium polyphosphate, and melamine-modified ammonium polyphosphate.

[0058] Among the inorganic phosphate compounds, ammonium hydrogen phosphite is preferred. It should be noted that the content of the inorganic phosphate compound relative to 100 parts by weight of the matrix polymer is, for example, 200 parts by weight or less, preferably 3 to 200 parts by weight, more preferably 5 to 150 parts by weight, and even more preferably 10 to 100 parts by weight. If the content of the inorganic phosphate compound is within the above range, the rubber composition exposed to high temperatures and carbonized will not deform, and its shape stability is improved.

[0059] <Fibrous organic compounds>

[0060] The fibrous organic compound can be in any fibrous shape. Examples of cross-sectional shapes for the fibers include circular, elliptical, and polygonal shapes. If the average fiber length of the fibrous organic compound is defined as L, and the average diameter as D, then L / D, for example, exceeds 10, preferably 50 or more, and more preferably 100 or more. No specific upper limit is specified, but for example, 10,000. The average diameter of the fibrous organic compound is, for example, 1 to 100 μm, preferably 2 to 50 μm, and more preferably 5 to 20 μm. The average fiber length of the fibrous organic compound is preferably, for example, 0.5 to 10 mm. This value is, for example, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0 mm, or any value between two of the values ​​exemplified here.

[0061] Examples of fibrous organic compounds include: meta-aromatic polyamide fibers, para-aromatic polyamide fibers, amide fibers, cellulose fibers (e.g., pulp fibers), poly(p-phenylenebenzobisoxazole) fibers, polyarylate fibers, polyester fibers, acrylic fibers, acrylonitrile fibers, rayon, silk, cotton, linen, wool, etc.

[0062] The average fiber length and average diameter of fibrous organic compounds are determined by measuring the fiber length and diameter of a sufficient number of fibrous organic compounds, i.e., more than 20, and the average value of these measurements is taken as the average fiber length and average diameter.

[0063] The fiber length and diameter of fibrous organic compounds can be measured, for example, using a field emission scanning electron microscope (FE-SEM).

[0064] The content of the fibrous organic compound relative to 100 parts by weight of the matrix polymer is, for example, 30 parts by weight or less, preferably 1 to 30 parts by weight, more preferably 3 to 24 parts by weight, and even more preferably 6 to 17 parts by weight. The content of the fibrous organic compound relative to 100 parts by weight of the matrix polymer is, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 parts by weight, or may be within any range of the values ​​exemplified herein. By having the content of the fibrous compound within this range, the balance between the cohesiveness and adhesiveness of the rubber composition is improved.

[0065] <Plasticizers (Softeners)>

[0066] The content of the plasticizer relative to 100 parts by mass of the matrix polymer is, for example, 16 parts by mass or less, preferably 0.5 to 15 parts by mass, and more preferably 1 to 10 parts by mass. The content of the plasticizer relative to 100 parts by mass of the matrix polymer is, for example, 0, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 parts by mass, or may be within any two of the values ​​exemplified herein.

[0067] Anti-aging agents

[0068] The content of the anti-aging agent relative to 100 parts by weight of the matrix polymer is, for example, 10 parts by weight or less, preferably less than 2.5 parts by weight, and more preferably 0.5 to 2 parts by weight. The content of the anti-aging agent relative to 100 parts by weight of the matrix polymer is, for example, 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, or 10.0 parts by weight, or may be within any two of the values ​​exemplified herein.

[0069] The rubber composition of this embodiment can be molded in the following manner: the above components are mixed using a known mixing device such as a Banbury mixer, a kneading mixer, or a two-roll mixer, and then molded by a conventional molding method such as pressure molding, roll forming, extrusion molding, or calendering.

[0070] <Other Implementation Methods>

[0071] Furthermore, another embodiment of the battery of the present invention includes a component made of the aforementioned rubber composition. The battery typically has at least one battery cell 3, and the putty-like rubber composition (putty-like composition) is disposed in the battery as a protective material, refractory material, etc., component 1. Figure 1A rubber composition is typically disposed on the surface of the battery cell. A battery may have one battery cell or two or more.

[0072] In addition, battery cells may include: lithium-ion batteries, lithium-ion polymer batteries, nickel-hydrogen batteries, lithium-sulfur batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, sodium-sulfur batteries, lead-acid batteries, air batteries, and other secondary batteries, but are not limited to these.

[0073] Batteries are used in small electronic devices such as mobile phones and smartphones, laptops, automobiles, and power tools, but are not limited to these.

[0074] <Laminated Structure>

[0075] It should be noted that, as described above, the rubber composition of the present invention may contain thermally expandable graphite, and in one embodiment of the present invention, it may also be provided in the form of a laminate containing layers such as refractory sheets containing thermally expandable graphite.

[0076] The laminate may include, for example, a first layer and a second layer disposed on the first layer, either directly or intervening in other layers. The first layer is composed of the aforementioned rubber composition.

[0077] The second layer is composed of a thermally expandable composition containing thermally expandable graphite. In addition to thermally expandable graphite, the thermally expandable composition may further contain a matrix polymer or inorganic compounds.

[0078] The matrix polymer contained in the thermally expandable composition as the second layer is not particularly limited, and examples include: rubber, elastomers, thermoplastic resins, thermosetting resins, etc. It may be the same as or different from the matrix polymer contained in the aforementioned rubber composition.

[0079] The inorganic compound contained in the thermal expansion composition as the second layer is not particularly limited, and may be selected from the same options as the inorganic compound (metal hydroxide or inorganic compound other than metal hydroxide) that may be contained in the rubber composition of the first layer.

[0080] It may be the same as or different from the inorganic compounds contained in the rubber composition of the first layer.

[0081] The thermally expandable graphite contained in the second layer of the thermally expandable composition may be selected from the same options as the thermally expandable graphite contained in the first layer of the rubber composition.

[0082] The content of thermally expandable graphite in the second layer of the thermally expandable composition is preferably 1 to 300 parts by weight relative to 100 parts by weight of the matrix polymer, more preferably 20 to 200 parts by weight, and even more preferably 30 to 150 parts by weight.

[0083] It should be noted that, in one example, the structure may be one in which the first layer does not contain thermally expandable graphite and the second layer does contain thermally expandable graphite, while in another example, the structure may be one in which both the first and second layers contain thermally expandable graphite.

[0084] The thickness of the second layer is not particularly limited, but is preferably 0.1 to 20 mm.

[0085] The thickness of the laminate is not particularly limited, but is preferably 0.2 to 40 mm.

[0086] The thickness ratio of the first layer to the second layer is not particularly limited, but is preferably 1:200 (e.g., 0.1mm:20mm) to 200:1 (e.g., 20mm:0.1mm).

[0087] In addition, the above-mentioned stacked body can be used as a battery component, and a battery according to one embodiment may include the above-mentioned stacked body.

[0088] [Example]

[0089] The present invention will be specifically described below through examples and comparative examples, but the present invention is not limited to these examples.

[0090] 1. Preparation of rubber composition

[0091] The components shown in Tables 1 to 3 were mixed at 80°C for 10 minutes using a 3-liter kneading mixer to obtain the rubber compositions of the examples and comparative examples as test pieces.

[0092] [Table 1]

[0093]

[0094] [Table 2]

[0095]

[0096] [Table 3]

[0097]

[0098] The ingredients in the table are detailed below.

[0099] (1) Matrix polymer

[0100] Liquid rubber

[0101] Liquid polyisoprene: "LIR-30" manufactured by Kuraray Co., Ltd., with a molecular weight of 28,000, Tg: -63℃, and viscosity of 70 Pa·s (38℃).

[0102] Liquid polybutadiene: "LBR-302" manufactured by Kuraray Co., Ltd., with a molecular weight of 5500, Tg: -85℃, and viscosity of 0.6 Pa·s (38℃).

[0103] Liquid polybutene: Manufactured by JX Energy Corporation, “HV-100”, molecular weight 980, kinematic viscosity 9,500 mmHg 2 / s(40℃)

[0104] Solid Elastomers

[0105] Butyl rubber: "BUTYL 268" manufactured by JSR Corporation, rubbery, softness (21℃) 25 [1 / 10mm]

[0106] EPDM: "EP51" manufactured by JSR Corporation, rubber-like, softness (21℃) 17 [1 / 10mm]

[0107] NBR: "Nipol DN401" manufactured by Nippon Zeon Corporation, rubber-like, softness (21℃) 13 [1 / 10mm]

[0108] (2) Metal hydroxides

[0109] Aluminum hydroxide (Al hydroxide): "C-301N" manufactured by Sumitomo Chemical Co., Ltd.

[0110] Calcium hydroxide (Ca hydroxide): "Quick lime" manufactured by Maruai Lime Industries, Inc.

[0111] Magnesium hydroxide (Mg hydroxide): "KISMA5A" manufactured by Kyowa Chemical Industry Co., Ltd.

[0112] (3) Other ingredients

[0113] <Other Resins>

[0114] EVA: "EVAFLEX EV460" manufactured by DuPont-Mitsui Polychemicals Co., Ltd., resinous, softness (21°C) 7 [1 / 10 mm]

[0115] <Inorganic compounds other than metal hydroxides>

[0116] Calcium carbonate (Ca): "TA-044" manufactured by Chichibu Lime Industry Co., Ltd.

[0117] 2. Evaluation

[0118] The rubber compositions of each embodiment and comparative example were subjected to the following tests and evaluations. The results are shown in Tables 1 to 3. As shown in Tables 1 to 3, all embodiments showed good conformability, adhesion, workability (non-adhesiveness), and fire extinguishing properties. On the other hand, at least one of these evaluation items was unsatisfactory in all comparative examples.

[0119] <Follow-up nature (softness)>

[0120] For the test specimens, softness was determined according to JIS A5752 at a load of 150g and a temperature of 21°C. A specified cone was vertically inserted into the specimen, and the penetration depth was measured in units of 0.1mm. Then, based on the penetration depth, processability was determined according to the following criteria.

[0121] ◎:60[1 / 10mm] or more

[0122] ○: 50 [1 / 10 mm] or more and less than 60 [1 / 10 mm]

[0123] Δ: 40 [1 / 10 mm] or more and less than 50 [1 / 10 mm]

[0124] ×: Less than 40 [1 / 10mm]

[0125] <Adhesiveness>

[0126] like Figure 2 As shown, using two aluminum plates 7 as specified in JIS H4000 (A1050), a 3g spherical specimen 5 was clamped and compressed to a thickness of 5mm. After 1 minute, vertical peeling was performed at a peeling speed of 300mm / min, and the adhesion was determined by the peak strength at the time of peeling. Then, the adhesion was judged according to the following criteria.

[0127] ◎: 3[N] or more

[0128] ○: 2[N] or more and less than 3[N]

[0129] Δ: 1 [N] or more and less than 2 [N]

[0130] ×: Less than 1 [N]

[0131] <Operational (Non-adhesive)>

[0132] After determining the quality of the latex rubber glove, the glove was worn, and a 100g spherical test piece (putty) was grasped 10 times. The weight of the residue adhering to the glove was then measured, and calculated based on the following formula. Based on the residue weight, the non-adhesion property was then determined according to the following evaluation criteria.

[0133] Weight of the attached material [g] = (Weight of the glove after gripping putty 10 times) - (Original weight of the glove)

[0134] [Evaluation Criteria]

[0135] ◎: The weight of the attached substance is less than 0.5g.

[0136] ○: The weight of the attached substance is 0.5g or more but less than 1.0g.

[0137] Δ: The weight of the attached substance is 1.0 g or more and less than 1.5 g.

[0138] ×: The weight of the attached substance is 1.5g or more.

[0139] Fire extinguishing properties

[0140] A sample was prepared by arranging test pieces around the laminated lithium-ion battery used in smartphones, covering the entire battery. The sample was then placed on a hot plate set to 300°C, and the time from ignition to extinguishment was evaluated. It should be noted that a shorter extinguishing time indicates superior fire extinguishing performance.

[0141] ◎: Extinguishing time is less than 3 seconds

[0142] ○: Extinguishing time is more than 3 seconds and less than 5 seconds

[0143] Δ: Extinguishing time is more than 5 seconds and less than 10 seconds

[0144] ×: Extinguishing time is more than 10 seconds.

Claims

1. A rubber composition comprising, for every 100 parts by weight of a base polymer, 50 to 2000 parts by weight of a metal hydroxide. The matrix polymer comprises liquid rubber and solid elastomer, and the mass ratio of the liquid rubber to the solid elastomer is 95:5 to 50:

50.

2. The rubber composition according to claim 1, wherein, The metal hydroxide includes aluminum hydroxide.

3. The rubber composition according to claim 1, wherein, The content of inorganic compounds other than the metal hydroxide is less than 50 parts by mass relative to 100 parts by mass of the matrix polymer.

4. The rubber composition according to claim 1, wherein, The solid elastomer is rubber-like.

5. The rubber composition according to claim 1, wherein it is in putty form.

6. The rubber composition according to any one of claims 1 to 5, used in a battery.

7. A battery comprising a component made of the rubber composition according to any one of claims 1 to 5.

Images