Polyketone composition with excellent fire resistance and thermal runaway prevention performance

Abstract

To provide a polyketone resin composition that does not significantly increase the content of flame retardants while exhibiting excellent flame retardancy and fire resistance. [Solution] The polyketone resin composition comprises 29% to 34% by weight of polyketone resin, 10% to 50% by weight of glass fiber, 10% to 50% by weight of fire-resistant material, and 5% to 8% by weight of flame retardant.

Description

Technical Field

[0001] The present invention relates to a polyketone resin composition, and particularly to a polyketone resin composition excellent in flame retardancy and fire resistance.

Background Art

[0002] Batteries used in environment-friendly vehicles such as electric vehicles, hydrogen electric vehicles, hybrid vehicles, and plug-in hybrid vehicles, and energy storage systems (Energy Storage System) are required to have high flame retardancy and high fire resistance for parts such as battery housings, inverter housings, and battery bus bars due to thermal runaway and safety issues.

[0003] In particular, the thermal runaway phenomenon is a phenomenon in which the internal temperature of the battery rapidly rises while the chain heat generation is accelerated, and it becomes the standard for high flame retardancy and high fire resistance required for battery parts to prevent fires and explosions in vehicles and energy storage systems.

[0004] Polyketone resin is a kind of high-performance thermoplastic polymer, and is a terpolymer or higher copolymer composed of carbon monoxide, ethylenically unsaturated compounds, and one or more olefinically unsaturated hydrocarbon compounds.

[0005] In particular, a polyketone resin having a structure in which the repeating units of carbon monoxide, the repeating units of ethylenically unsaturated compounds, and the repeating units of propylenically unsaturated compounds are substantially alternately linked is excellent in mechanical properties, thermal properties and processability, and has high flame retardancy, impact resistance, abrasion resistance, chemical resistance, calcium chloride resistance, antifreeze resistance, moisture absorption resistance, and gas barrier properties, and thus is a useful material for various applications.

[0006] Polyketone resins form char during combustion, with water being generated by the reaction of ketone groups (C=O) with hydrogen. This char layer blocks oxygen and heat, thus providing flame retardancy. Furthermore, their polymer structure, based solely on carbonyl and olefin groups, results in low toxicity of the gases produced during combustion.

[0007] However, the flame retardancy of polyketone resin alone is insufficient to satisfy the high level of flexibility and fire resistance required to overcome battery thermal runaway environments. Adding a flame retardant to solve this problem (see "Patent Document 1" below) would significantly increase the manufacturing cost of the product, along with the recent surge in the price of flame retardants, making it difficult to widely utilize the product in diverse applications. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] KR10-2024-0022996A Statement [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention aims to provide a polyketone resin composition that exhibits excellent flame retardancy and fire resistance without significantly increasing the content of flame retardants. [Means for solving the problem]

[0010] The polyketone resin composition according to the present invention, which solves the above-mentioned problems, is characterized by comprising 29% to 34% by weight of polyketone resin, 10% to 50% by weight of glass fiber, 10% to 50% by weight of fire-resistant material, and 5% to 8% by weight of flame retardant. [Effects of the Invention]

[0011] The polyketone resin composition according to the present invention can be applied to all industries using environmentally friendly automobiles, energy storage devices, and other lithium batteries by significantly improving the flame retardancy and fire resistance of polyketone without greatly increasing the content of flame retardants. [Modes for carrying out the invention]

[0012] The present invention will be described in detail below. However, detailed explanations of known functions and configurations that may obscure the gist of the present invention will be omitted.

[0013] The polyketone resin composition according to the present invention is characterized by comprising 29% to 34% by weight of polyketone resin, 10% to 50% by weight of glass fiber, 10% to 50% by weight of fire-resistant material, and 5% to 8% by weight of flame retardant.

[0014] Furthermore, the polyketone resin composition according to the present invention may further contain 0.2% to 1.0% by weight of tricalcium phosphate.

[0015] Furthermore, the polyketone resin composition according to the present invention may further contain 0.1% to 0.5% by weight of an antioxidant.

[0016] Furthermore, the polyketone resin composition according to the present invention may further contain 0.7% to 1.5% by weight of a black masterbatch.

[0017] The polyketone resin preferably has a structure in which repeating units of carbon monoxide, repeating units of ethylenically unsaturated compounds, and repeating units of propylene unsaturated compounds are substantially alternately linked. Polyketone resins having such a structure have a melting index (220°C, 2.16 kg) of 200 g / 10 min to 55 g / 10 min, and not only are they easy to mold, but they also have excellent mechanical and thermal properties, and are useful for a variety of applications because they are highly flame retardant, impact resistant, abrasion resistant, chemical resistant, calcium chloride resistant, antifreeze resistant, moisture resistant, and gas barrier.

[0018] In the present invention, the polyketone resin is preferably 29% to 34% by weight of the total composition. However, if it is less than 29% by weight, there is a problem that the effect of improving the mechanical properties, thermal properties, and flame retardancy of the composition will be reduced, while if it exceeds 34% by weight, there is a problem that the effect of improving the fire resistance of the composition will be reduced.

[0019] Glass fiber, as a type of inorganic silicate fiber, is an artificial fiber made by forming molten glass into fibers, and is classified into long fibers and short fibers depending on the manufacturing method and application. Industrially, electro-glass (E-glass) fibers, which have good electrical insulation properties, are most widely used for resin reinforcement. As a product manufactured using glass as a base, it has high strength such as tensile strength, can withstand high temperatures well, is chemically durable and does not corrode, and improves mechanical properties such as heat resistance and electrical insulation.

[0020] The glass fibers used in the present invention may include one or more long fibers and short fibers. In addition, in the present invention, the glass fibers are preferably 10% to 50% by weight of the total composition, but if they are less than 10% by weight, there is a problem that the effect of improving the strength, heat resistance, and electrical insulation of the composition will be reduced, while if they exceed 50% by weight, there is a problem that the effect of improving the fire resistance of the composition will be reduced.

[0021] The aforementioned fire-resistant material is intended to improve the fire resistance of the composition, and in the present invention, it is preferable that it constitutes 10% to 50% by weight of the total composition. If it is less than 10% by weight, there is a problem that the effect of improving the fire resistance of the composition will be reduced, while if it exceeds 50% by weight, there is a problem that the effect of improving the strength of the composition will be reduced, so it is preferable to be within the above range.

[0022] In the present invention, preferably, any one of borosilicate glass, kaolin, glass beads, mica, magnesium hydroxide, and fine ceramics is used as the refractory material.

[0023] Borosilicate glass is a glass containing silica (SiO2), boron oxide (B2O3), sodium oxide (Na2O), potassium oxide (K2O), and aluminum oxide (Al2O3) as the main glass-forming components. It has high durability, a low expansion coefficient, a low density, and a high softening point compared to other glass types. It is superior in thermal shock and high-temperature stability compared to general glass, and has a melting point of 1,320 °C, so it has excellent fire resistance at high temperatures.

[0024] Kaolin has the chemical formula Al2O3·2SiO2·2H2O and is an inorganic substance mainly composed of kaolinite and halloysite. It has a melting point of 1,750 °C and is excellent in improving the thermal stability, chemical resistance, and surface appearance of engineering plastics.

[0025] Glass beads are small and round bead-shaped substances made of glass. They have strong chemical resistance and show the characteristic of withstanding high temperatures well because their melting point is 1,350 °C. Since they are non-directional, they can evenly disperse components in engineering plastics, reduce the shrinkage deformation of injection-molded products, and improve dimensional stability.

[0026] Mica is a hydrated aluminum silicate mineral and a rock-forming mineral with a thin plate-like structure. Mica generally has the chemical formula KAl3Si3O 10 (OH)2, has a hexagonal plate-like crystal structure, has a hardness of 2.5 Mohs to 4.0 Mohs, and is very excellent in electrical properties such as conductivity and electrical resistance, so it is used as an insulating material. As an asbestos substitute, it is excellent in fire resistance, heat resistance, and chemical resistance, and is excellent in thermal stability due to its low thermal conductivity.

[0027] Magnesium hydroxide has the chemical formula MgOH2 and a high endothermic decomposition point of 332°C. This has the advantage of raising the ignition point when added to other substances or reactions, and producing less smoke in the flame. As a non-polluting inorganic material, it is widely used in electric wires and cables. When applied to automotive parts, it has the advantage of producing less smoke in the event of a fire in an internal combustion engine or electric vehicle.

[0028] Fine ceramics are high-performance ceramic materials made from inorganic compounds synthesized from high-purity natural or artificial inorganic materials. Representative fine ceramic materials include alumina (Al2O3), silicon nitride (Si3N4), zirconia (ZrO2), and silicon carbide (SiC).

[0029] Alumina is the most versatile fine ceramic material. It is a compound of aluminum and oxygen, with the chemical formula Al2O3. With a melting point of 2,054°C, it has excellent fire resistance, heat resistance, electrical insulation, and high thermal conductivity, making it widely used in the automotive industry, especially in the electric vehicle sector.

[0030] Silicon nitride is a material with high strength and excellent thermal shock resistance. It is a ceramic in which nitrogen and silicon are bonded in a Si3N4 composition. It is lightweight, has excellent high-temperature strength and fracture toughness, and possesses superior wear resistance, corrosion resistance, and thermal shock resistance. With a melting point of 1,850°C, it is used in automobile engine parts, electronic components, industrial machinery parts, and various composite materials.

[0031] Zirconia is a non-metallic inorganic material, a high-performance ceramic material with high toughness and wear resistance. It is a zirconium (Zr) compound produced through zircon (ZrSiO4) mineral, and has a melting point of 2,715°C, making it suitable for use as a refractory material and refractory ceramic.

[0032] Silicon carbide is a compound composed of silicon and carbon, and is a material with high-temperature strength and excellent wear resistance. Compared to silicon, it has lower resistance, higher strength and thermal conductivity, a melting point of 2,730°C, and excellent physical and chemical properties, making it widely used in parts that operate under harsh conditions such as high temperature, high pressure, and corrosive environments.

[0033] The aforementioned flame retardant is for improving the flame retardancy of the composition, and in the present invention, it is preferably 5% to 8% by weight of the total composition. If it is less than 5% by weight, there is a problem that the effect of improving the flame retardancy of the composition will be reduced, while if it exceeds 8% by weight, there is a problem that the manufacturing cost of the composition will increase, so it is preferable to be within the above range.

[0034] In the present invention, a phosphorus-based flame retardant or an inorganic flame retardant may be used as the flame retardant.

[0035] Phosphorus-based flame retardants, when burned, decompose various phosphate compounds such as phosphoric acid, hypophosphorous acid, and polyphosphate into oxygen acids. This dehydrates the material through a strong dehydrating action, causing it to carbonize and form a coating, thereby reducing the amount of flammable product.

[0036] Inorganic flame retardants are environmentally friendly flame retardants. For example, aluminum phosphinate has the advantage of excellent corrosion resistance and the absence of aggregation through special surface treatment.

[0037] The tricalcium phosphate (TCP) mentioned above prevents a decline in the mechanical properties of the polyketone resin and carbonization that occurs during extrusion, thereby improving overall processing stability. It also prevents the polyketone resin from gelling at high temperatures or from increasing in viscosity, minimizing damage to the final injection-molded product. In this invention, the amount of TCP may be selectively 0.2% to 1.0% by weight of the overall composition.

[0038] The aforementioned antioxidants are intended to suppress oxidative decomposition of the composition due to reaction with metallic ions, and in the present invention, they may be selectively present in an amount of 0.1% to 0.5% by weight of the total composition.

[0039] The aforementioned black master batch is a coloring agent used to impart black color to a composition for use in automotive parts, electronic devices, etc., and in the present invention, it may be selectively present in an amount of 0.7% to 1.5% by weight of the total composition.

[0040] Thus, the polyketone resin composition according to the present invention has excellent flame retardancy and fire resistance. Therefore, it can be applied to all industries in which lithium batteries are used, in addition to environmentally friendly automobiles and energy storage devices.

[0041] <Examples> The present invention will be described in more detail below through examples. However, these examples are for illustrative purposes only and do not limit the scope of the present invention.

[0042] The physical properties of test specimens of the compositions produced according to Comparative Example 1 and Examples 1 to 6 below were measured using the following method, and the resulting values ​​are shown in Tables 1 to 7 below.

[0043] Experimental example: Method for measuring physical properties

[0044] 1) The flame retardancy test was conducted in accordance with UL94. A 20mm spark was applied to a 0.8mm thick test specimen for 10 seconds, the burning time of the specimen was measured, and then the 20mm spark was applied again for 10 seconds. The burning time of the specimen and the time until a spark was generated after burning were measured.

[0045] 2) The fire resistance test was conducted by applying a 1,200°C LPG torch flame from a distance of 5 cm to a test specimen measuring 20 cm x 20 cm x 2 mm for 10 minutes, and checking for the occurrence of holes in the test specimen.

[0046] 3) The Torch & Grit test was conducted in accordance with UL2596. A 1,200°C methane gas torch flame was applied to a 20cm x 20cm x 2mm test specimen from a distance of 6cm for 15 seconds. Then, 120-mesh size alumina particles were rapidly sprayed onto the specimen along with the flame for 5 seconds. One cycle was defined as this, and the test proceeded by measuring the total number of cycles performed until a hole appeared.

[0047] Comparative Example 1: Results of manufacturing and physical property measurement of a polyketone resin / glass fiber / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0048] A composition was prepared by mixing polyketone resin, glass fiber, flame retardant, tricalcium phosphate, antioxidant, and black masterbatch in the compositional ratios shown in Table 1 below, and then compounding the mixture in an extruder. Test specimens were then prepared, and the results of measuring their physical properties are shown in Table 1 below.

[0049] [Table 1]

[0050] Example 1: Manufacturing and property measurement results of a polyketone resin / glass fiber / borosilicate glass / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0051] Examples 1-1 to 1-5

[0052] Test specimens were prepared using the same method as in Comparative Example 1, based on the raw materials and composition ratios shown in Table 2 below. The results of measuring the physical properties are shown in Table 2 below.

[0053] [Table 2]

[0054] Example 2: Manufacturing and property measurement results of a polyketone resin / glass fiber / Takamine stone / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0055] Examples 2-1 to 2-5

[0056] Test specimens were prepared using the same method as in Comparative Example 1, based on the raw materials and composition ratios shown in Table 3 below. The results of measuring the physical properties are shown in Table 3 below.

[0057] [Table 3]

[0058] Example 3: Manufacturing and property measurement results of a polyketone resin / glass fiber / glass beads / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0059] Examples 3-1 to 3-5

[0060] Test specimens were prepared using the same method as in Comparative Example 1, based on the raw materials and composition ratios shown in Table 4 below. The results of measuring the physical properties are shown in Table 4 below.

[0061] [Table 4]

[0062] Example 4: Manufacturing and property measurement results of a polyketone resin / glass fiber / mica / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0063] Examples 4-1 to 4-5

[0064] Test specimens were prepared using the same method as in Comparative Example 1, based on the raw materials and composition ratios shown in Table 5 below. The results of measuring the physical properties are shown in Table 5 below.

[0065] [Table 5]

[0066] Example 5: Manufacturing and property measurement results of a polyketone resin / glass fiber / magnesium hydroxide / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0067] Examples 5-1 to 5-5

[0068] Test specimens were prepared using the same method as in Comparative Example 1, based on the raw materials and composition ratios shown in Table 6 below. The results of measuring the physical properties are shown in Table 6 below.

[0069] [Table 6]

[0070] Example 6: Manufacturing and property measurement results of a polyketone resin / glass fiber / fine ceramics / flame retardant / tricalcium phosphate / antioxidant / black masterbatch composition

[0071] Examples 6-1 to 6-5

[0072] Test specimens were prepared using the same method as in Comparative Example 1, based on the raw materials and composition ratios shown in Table 7 below. The results of measuring the physical properties are shown in Table 7 below.

[0073] [Table 7]

[0074] Through the results shown in Tables 1 to 7, it was confirmed that Examples 1 to 6, which included fire-resistant material, exhibited superior fire resistance and thermal runaway prevention performance compared to Comparative Example 1, which did not include inorganic reinforcing material.

[0075] In particular, the torch-and-grid test results, which confirm thermal runaway shutdown performance, showed a minimum value of 5 cycles or more in all of Examples 1 to 6. However, 10 cycles or more is the standard required for electric vehicle battery housings (Battery Module Assembly, BMA) and electric vehicle battery-related components, 7 cycles or more is the standard required for electric vehicle busbars and high-voltage components, and 5 cycles or more is the standard required for other electric vehicle high flame-retardant components. Therefore, each embodiment of the present invention is a polyketone resin composition with excellent flame retardancy and fire resistance that can be used in environmentally friendly automobiles (electric, hydrogen-electric, hybrid, and plug-in hybrid vehicles) and energy storage devices.

Claims

1. It contains 29% to 34% by weight of polyketone resin, 10% to 50% by weight of glass fiber, 10% to 50% by weight of fire-resistant material, and 5% to 8% by weight of flame retardant. The sum of the glass fiber and fire-resistant material is 60% by weight. It has fire resistance test performance of at least 5 minutes and torch and grid test performance of at least 5 cycles. A polyketone resin composition characterized by the following features.

2. The aforementioned fire-resistant material is borosilicate glass. The polyketone resin composition according to claim 1.

3. The aforementioned fire-resistant material is Takamine stone. The polyketone resin composition according to claim 1.

4. The aforementioned fire-resistant material is glass beads. The polyketone resin composition according to claim 1.

5. The aforementioned fire-resistant material is mica. The polyketone resin composition according to claim 1.

6. The aforementioned fire-resistant material is magnesium hydroxide. The polyketone resin composition according to claim 1.

7. The aforementioned fire-resistant material is a fine ceramic. The polyketone resin composition according to claim 1.

8. Further comprising 0.2% to 1.0% by weight of tricalcium phosphate The polyketone resin composition according to claim 1.

9. Further containing 0.1% to 0.5% by weight of an antioxidant The polyketone resin composition according to claim 1 or 8.

10. Further comprising 0.7% to 1.5% by weight of black masterbatch The polyketone resin composition according to claim 9.

Images