Flame-retardant battery ABS (Acrylonitrile Butadiene Styrene) plastic shell and preparation method thereof

Abstract

The invention discloses a flame-retardant battery ABS plastic shell and a preparation method thereof. According to the flame-retardant battery ABS plastic shell and the preparation method thereof, the flame-retardant property of the ABS plastic shell can be effectively improved, meanwhile, toxic gas released during combustion of the ABS plastic shell is reduced, the mechanical property of the ABS plastic shell can be improved, and the safety performance of the ABS plastic shell can be effectively improved; graphene oxide can play a role of a physical barrier in the aspect of flame retardance, and the compactness and continuity of a carbon layer are improved, so that exchange of heat and oxygen generated in the combustion process is isolated; the polyethyleneimine is grafted on the surface of the graphene oxide, so that the dispersion uniformity of the graphene oxide in the ABS plastic can be effectively improved, and the flame retardant property of the ABS plastic shell is further effectively improved; pEI-GO has the capability of inhibiting release of PH3,-NH2 of PEI-GO can absorb PH3 through an oxidation reaction, and release of PH3 is reduced; the release time of PH3 is delayed, and the concentration is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of ABS plastic shells, and more particularly to a flame-retardant ABS plastic shell for a battery and a preparation method thereof. Background Art

[0002] ABS plastic is a terpolymer of acrylonitrile (A), butadiene (B), and styrene (S). ABS plastic has excellent electrical insulation and is virtually unaffected by temperature, humidity, and frequency, making it suitable for use in most environments. Therefore, it is widely used in electronic and electrical applications, and battery casings are often made of ABS plastic. However, ABS's mechanical properties are inferior to those of other plastics. Polycarbonate (PC) is a high-performance engineering plastic with advantages such as high strength, high toughness, and dimensional stability. PC / ABS composites offer excellent mechanical properties, good processability, superior thermal properties, high impact strength, stress cracking resistance, and weather resistance. Currently, PC / ABS composites have become one of the most widely used plastic alloys.

[0003] Polycarbonate (PC) has a limiting oxygen index (LOI) of 25% and achieves the UL-94V-2 rating in the vertical burning test. ABS releases large amounts of deadly smoke and toxic gases when burned, so it is necessary to flame-retardant modify PC / ABS composite plastics to improve their fire safety performance. Brominated flame retardants (FRs) are commonly used flame retardants in PC / ABS composite plastics, but due to the bioaccumulation and toxicity of halogens, they have gradually been banned. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a flame-retardant battery ABS plastic shell and a preparation method thereof.

[0005] A flame-retardant ABS plastic shell for a battery, the raw materials of which include: polycarbonate, acrylonitrile-butadiene-styrene copolymer, ethylene-methacrylic acid copolymer, carbon fiber and graphene oxide / aluminum hypophosphite hybrid.

[0006] Furthermore, the weight ratio of the polycarbonate to the acrylonitrile-butadiene-styrene copolymer is 7:3; the amount of the ethylene-methacrylic acid copolymer is 2.0% to 4.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the amount of the carbon fiber is 14.5% to 15.5% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; and the amount of the graphene oxide / aluminum hypophosphite hybrid is 7.5% to 8.5% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer.

[0007] Furthermore, the raw materials of the graphene oxide / aluminum hypophosphite hybrid include graphene oxide with polyethyleneimine grafted on the surface and aluminum hypophosphite; the weight ratio of the graphene oxide with polyethyleneimine grafted on the surface to aluminum hypophosphite is 1:95-105.

[0008] Furthermore, the raw materials of the graphene oxide with polyethyleneimine grafted on the surface include: polyethyleneimine, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, N-hydroxysuccinimide and graphene oxide.

[0009] Furthermore, the weight ratio of the graphene oxide to polyethylene imine is 1:8-10; the weight ratio of the graphene oxide to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:2-3; and the weight ratio of the graphene oxide to N-hydroxysuccinimide is 1:10-15.

[0010] Furthermore, the weight ratio of the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride to N-hydroxysuccinimide is 1:5.

[0011] Furthermore, the amount of the ethylene-methacrylic acid copolymer is 3.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the amount of the carbon fiber is 15.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the amount of the graphene oxide / aluminum hypophosphite hybrid is 8.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the weight ratio of the graphene oxide with surface grafted polyethyleneimine to aluminum hypophosphite is 1:100; the weight ratio of the graphene oxide to polyethyleneimine is 1:9; the weight ratio of the graphene oxide to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:2; and the weight ratio of the graphene oxide to N-hydroxysuccinimide is 1:10.

[0012] A method for preparing a flame-retardant battery ABS plastic shell is characterized in that the specific preparation steps are as follows: Step 1: Add a polyethyleneimine aqueous solution to a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride / N-hydroxysuccinimide aqueous solution and mix them. Then, dropwise add a dispersion of graphene oxide to the above solution, stir at room temperature for 24 hours, and dialyze to obtain a dispersion of graphene oxide with polyethyleneimine grafted on its surface. Step 2: adding a dispersion of graphene oxide with polyethyleneimine grafted on its surface to an aqueous dispersion of aluminum hypophosphite, stirring for 15 to 25 minutes, filtering to obtain a precipitate, and freeze-drying the precipitate for 24 hours to obtain a graphene oxide / aluminum hypophosphite hybrid; Step 3: drying the graphene oxide / aluminum hypophosphite hybrid, polycarbonate, acrylonitrile-butadiene-styrene copolymer, and carbon fiber at 75-85° C. for 11-13 hours; Step 4: Add polycarbonate, acrylonitrile-butadiene-styrene copolymer, ethylene-methacrylic acid copolymer, and graphene oxide / aluminum hypophosphite hybrid into a mixer and mix them evenly; add the mixture into a twin-screw extruder for melt blending, then add carbon fiber into the twin-screw extruder, evacuate, extrude the material, cool, dry, and pelletize to obtain flame-retardant battery ABS plastic masterbatch; Step 5: Feed the flame-retardant battery ABS plastic masterbatch into an injection molding machine for injection molding to obtain a flame-retardant battery ABS plastic shell.

[0013] Furthermore, in step 1, the concentration of the polyethyleneimine aqueous solution is 9-11 mg / ml, the concentration of the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride / N-hydroxysuccinimide aqueous solution is 11-13 mg / ml, the concentration of the graphene oxide dispersion is 0.9-1.1 mg / ml, and the stirring speed is 120-180 r / min; in step 2, the concentration of the graphene oxide dispersion with surface grafted polyethyleneimine is 0.38-0.42 mg / ml, the concentration of the aqueous dispersion of aluminum hypophosphite is 75-85 mg / ml, and the stirring speed is 600-900 r / min.

[0014] Furthermore, in step four, the screw speed of the twin-screw extruder is 110-130 r / min, the extrusion temperature is 240-250°C, the material is water-cooled after extrusion, and dried in a drying oven at 55-65°C; in step five, the injection pressure is 75-85 MPa and the injection temperature is 245-255°C.

[0015] Technical effects and advantages of the present invention: 1. The flame-retardant ABS plastic shell of the present invention can effectively improve the flame retardancy of the ABS plastic shell, while reducing the toxic gases released by the ABS plastic shell during combustion, thereby improving the mechanical properties of the ABS plastic shell and effectively improving the safety performance of the ABS plastic shell; graphene oxide can act as a physical barrier in terms of flame retardancy, improving the density and continuity of the carbon layer, thereby isolating the heat generated during the combustion process and the exchange of oxygen; polyethyleneimine is grafted onto the surface of graphene oxide, which can effectively improve the dispersion uniformity of graphene oxide in ABS plastic, thereby effectively improving the flame retardancy of the ABS plastic shell; graphene oxide with polyethyleneimine grafted on the surface (PEI-GO) has the ability to inhibit the release of PH3; the -NH2 of PEI-GO can absorb PH3 through an oxidation reaction to form an -NH-PH2=O structure, reducing the release of PH3, thereby delaying the release time of PH3 and reducing the PH3 concentration; 2. In the present invention, CF is dispersed in the ABS composite material to gradually form a mutually overlapping network structure. CF can bear the main external load, and the network structure formed by CF can inhibit the expansion of cracks inside the composite material, which helps the composite material have a greater load-bearing capacity, thereby effectively improving the tensile strength and flexural strength of the ABS composite material. Carbon fibers (CF) are dispersed in the composite material to form an interlaced network structure, which inhibits the movement of macromolecular chains in the ABS composite material, thereby increasing the difficulty of deformation of the ABS composite material and increasing the thermal deformation temperature of the composite material. DETAILED DESCRIPTION

[0016] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention. Example

[0017] The present invention provides a flame-retardant ABS plastic shell for batteries, the raw materials of which include: polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), ethylene-methacrylic acid copolymer (EMAC), carbon fiber (CF) and graphene oxide / aluminum hypophosphite hybrid; The weight ratio of the polycarbonate (PC) to the acrylonitrile-butadiene-styrene copolymer (ABS) is 7:3; the amount of the ethylene-methacrylic acid copolymer (EMAC) is 2.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the carbon fiber (CF) is 14.5% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); and the amount of the graphene oxide / aluminum hypophosphite hybrid is 7.5% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS). The raw materials of the graphene oxide / aluminum hypophosphite hybrid include graphene oxide with polyethyleneimine grafted on the surface and aluminum hypophosphite (AHP); the weight ratio of the graphene oxide with polyethyleneimine grafted on the surface to aluminum hypophosphite (AHP) is 1:95; The raw materials of the graphene oxide with polyethyleneimine grafted on the surface include polyethyleneimine (PEI), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC-HCl), N-hydroxysuccinimide (NHS) and graphene oxide (GO); The weight ratio of the graphene oxide (GO) to polyethyleneimine (PEI) is 1:8; the weight ratio of the graphene oxide (GO) to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC-HCl) is 1:2; and the weight ratio of the graphene oxide (GO) to N-hydroxysuccinimide (NHS) is 1:10. A method for preparing a flame-retardant battery ABS plastic shell is characterized in that the specific preparation steps are as follows: Step 1: Add a 10 mg / ml polyethyleneimine aqueous solution to a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride / N-hydroxysuccinimide aqueous solution (12 mg / ml, EDC-HCl to NHS weight ratio of 1:5) and mix. Then, add a 1.0 mg / ml graphene oxide dispersion dropwise to the above solution. Stir at room temperature for 24 hours and dialyze to obtain a graphene oxide dispersion with polyethyleneimine grafted on its surface. Step 2: Adding a dispersion of polyethyleneimine-grafted graphene oxide (4.0 mg / ml) to an aqueous dispersion of aluminum hypophosphite (80 mg / ml), stirring for 20 minutes (at a stirring speed of 750 rpm), filtering to obtain a precipitate, and freeze-drying the precipitate for 24 hours to obtain a graphene oxide / aluminum hypophosphite hybrid; Step 3: drying the graphene oxide / aluminum hypophosphite hybrid, polycarbonate, acrylonitrile-butadiene-styrene copolymer, and carbon fiber at 80° C. for 12 h; Step 4: Add polycarbonate, acrylonitrile-butadiene-styrene copolymer, ethylene-methacrylic acid copolymer, and graphene oxide / aluminum hypophosphite hybrid into a mixer and mix them evenly; add the mixture into a twin-screw extruder for melt blending (screw speed 120r / min, extrusion temperature 245°C), add carbon fiber into the twin-screw extruder, evacuate, extrude the material, water-cool, dry in a 60°C drying oven, and pelletize to obtain flame-retardant battery ABS plastic masterbatch; Step 5: The flame-retardant battery ABS plastic masterbatch is fed into an injection molding machine for injection molding (injection pressure 80 MPa, injection temperature 250°C) to obtain a flame-retardant battery ABS plastic shell. Example

[0018] The difference from Example 1 is that the amount of the ethylene-methacrylic acid copolymer (EMAC) is 4.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the carbon fiber (CF) is 15.5% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the graphene oxide / aluminum hypophosphite hybrid is 1.5% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS). 8.5% by weight; the weight ratio of the graphene oxide with polyethyleneimine grafted on the surface to aluminum hypophosphite (AHP) is 1:105; the weight ratio of the graphene oxide (GO) to polyethyleneimine (PEI) is 1:10; the weight ratio of the graphene oxide (GO) to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC-HCl) is 1:3; the weight ratio of the graphene oxide (GO) to N-hydroxysuccinimide (NHS) is 1:15. Example

[0019] The difference from Example 1 is that the amount of the ethylene-methacrylic acid copolymer (EMAC) is 3.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the carbon fiber (CF) is 15.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the graphene oxide / aluminum hypophosphite hybrid is 1.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS). 8.0% of the total weight; the weight ratio of the graphene oxide with polyethyleneimine grafted on the surface to aluminum hypophosphite (AHP) is 1:100; the weight ratio of the graphene oxide (GO) to polyethyleneimine (PEI) is 1:9; the weight ratio of the graphene oxide (GO) to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC-HCl) is 1:2; the weight ratio of the graphene oxide (GO) to N-hydroxysuccinimide (NHS) is 1:10.

[0020] Comparative Example 1: Different from Example 3, a flame-retardant battery ABS plastic shell comprises raw materials including polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS); the weight ratio of the polycarbonate (PC) to the acrylonitrile-butadiene-styrene copolymer (ABS) is 7:3; A method for preparing a flame-retardant battery ABS plastic shell is characterized in that the specific preparation steps are as follows: Step 1: drying polycarbonate and acrylonitrile-butadiene-styrene copolymer at 80°C for 12 hours; Step 2: Add polycarbonate and acrylonitrile-butadiene-styrene copolymer into a mixer and mix them evenly; add the mixture into a twin-screw extruder for melt blending (screw speed 120r / min, extrusion temperature 245℃), evacuate, extrude the material, cool it with water, dry it in a drying oven at 60℃, and pelletize it to obtain flame-retardant battery ABS plastic masterbatch; Step 3: The flame-retardant battery ABS plastic masterbatch is fed into an injection molding machine for injection molding (injection pressure 80 MPa, injection temperature 250°C) to obtain a flame-retardant battery ABS plastic shell.

[0021] Comparative Example 2: Different from Example 3, a flame-retardant battery ABS plastic shell, the raw materials include: polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), ethylene-methacrylic acid copolymer (EMAC), carbon fiber (CF); The weight ratio of the polycarbonate (PC) to the acrylonitrile-butadiene-styrene copolymer (ABS) is 7:3; the amount of the ethylene-methacrylic acid copolymer (EMAC) is 3.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the carbon fiber (CF) is 15.0% of the total weight of the polycarbonate (PC) and the acrylonitrile-butadiene-styrene copolymer (ABS); A method for preparing a flame-retardant battery ABS plastic shell is characterized in that the specific preparation steps are as follows: Step 1: drying polycarbonate, acrylonitrile-butadiene-styrene copolymer, and carbon fiber at 80°C for 12 hours; Step 2: Add polycarbonate, acrylonitrile-butadiene-styrene copolymer, and ethylene-methacrylic acid copolymer into a mixer and mix them evenly; add the mixture into a twin-screw extruder for melt blending (screw speed 120r / min, extrusion temperature 245°C), add carbon fiber into the twin-screw extruder, vacuumize, extrude the material, water-cool, dry in a 60°C drying oven, and pelletize to obtain flame-retardant battery ABS plastic masterbatch; Step 3: The flame-retardant battery ABS plastic masterbatch is fed into an injection molding machine for injection molding (injection pressure 80 MPa, injection temperature 250°C) to obtain a flame-retardant battery ABS plastic shell.

[0022] Comparative Example 3: Different from Example 3, a flame-retardant battery ABS plastic shell comprises raw materials including: polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), ethylene-methacrylic acid copolymer (EMAC), carbon fiber (CF) and aluminum hypophosphite; the amount of the ethylene-methacrylic acid copolymer (EMAC) is 3.0% of the total weight of the polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS); the amount of the carbon fiber (CF) is 15.0% of the total weight of the polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS); and the amount of the aluminum hypophosphite is 8.0% of the total weight of the polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS); A method for preparing a flame-retardant battery ABS plastic shell is characterized in that the specific preparation steps are as follows: Step 1: drying aluminum hypophosphite, polycarbonate, acrylonitrile-butadiene-styrene copolymer, and carbon fiber at 80° C. for 12 h; Step 2: Add polycarbonate, acrylonitrile-butadiene-styrene copolymer, ethylene-methacrylic acid copolymer, and aluminum hypophosphite into a mixer and mix them evenly; add the mixture into a twin-screw extruder for melt blending (screw speed 120r / min, extrusion temperature 245°C), add carbon fiber into the twin-screw extruder, evacuate, extrude the material, water-cool, dry in a 60°C drying oven, and pelletize to obtain flame-retardant battery ABS plastic masterbatch; Step 3: The flame-retardant battery ABS plastic masterbatch is fed into an injection molding machine for injection molding (injection pressure 80 MPa, injection temperature 250°C) to obtain a flame-retardant battery ABS plastic shell.

[0023] Among the above raw materials, polycarbonate (PC), 141R-111, was purchased from Shanghai Xingxiang Plastic Co., Ltd.; acrylonitrile-butadiene-styrene (ABS, 0215A) was purchased from Jilin Petrochemical Co., Ltd.; carbon fiber (CF), T300, length 3-5 mm, diameter 7 μm, was purchased from Toray Industries, Ltd. of Japan; aluminum hypophosphite (AHP, ≥98%, national medicine code: XW01778422702), polyethyleneimine (PEI, ≥99%, national medicine code: XW01900298603) and N-hydroxysuccinimide (NHS, ≥98%, national medicine code: TH062325G) were all purchased from Sinopharm Chemical Reagent Co., Ltd.; 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC-HCl, ≥98.5%) was purchased from Shanghai Yuanye Biotechnology Co., Ltd., product number: S30054.

[0024] Performance test experiment of flame retardant battery ABS plastic shell: The performance of the flame retardant battery ABS plastic shell in the embodiment and the comparative example was tested; Mechanical properties test: Tensile strength is tested according to GB / T1040.2-2022, sample size is 110mm×10mm×4mm, tensile rate is 20mm / min; The bending strength was tested according to GB / T9341-2008, with a sample size of 80 mm × 10 mm × 4 mm and a bending rate of 2 mm / min. Impact strength refers to Method A in ASTM D256-2010E, with an impact energy of 2.75 J; According to the ASTM D2863 standard, the LOI value of the flame-retardant battery ABS plastic shell was measured using the LOI901 Limiting Oxygen Index (LOI) tester from the German Netzsch Taurus Instrument Company. According to ASTM D3801-2010, vertical combustion test (UL-94) was conducted on flame-retardant ABS plastic shell of battery using CZF-3 vertical combustion apparatus from Jiangning Analytical Instrument Co., Ltd., China. The BWMCXL-4 toxic gas detector from Honeywell (USA) was used to detect the concentration of phosphine (PH3) during the combustion of flame-retardant battery ABS plastic shells in a confined space (30cm×30cm×45.0cm); The results are shown in Table 1: Table 1:

[0025] The flame-retardant battery ABS plastic shell of the present invention can effectively improve the flame retardancy of the ABS plastic shell, while reducing the toxic gas released when the ABS plastic shell burns, improving the mechanical properties of the ABS plastic shell, and effectively improving the safety performance of the ABS plastic shell; Graphene oxide (GO) is a two-dimensional nanosheet with a high specific surface area. Graphene oxide can act as a physical barrier in flame retardancy, improving the density and continuity of the carbon layer, thereby isolating the heat and oxygen exchange generated during the combustion process. After introducing organic functional groups such as -NH2, -OH and epoxy groups on the surface of graphene oxide (GO), the compatibility of graphene oxide (GO) with polymers can be effectively improved, and graphene oxide (GO) can be evenly dispersed in the polymer matrix. In the present invention, polyethyleneimine is grafted on the surface of graphene oxide, which can effectively improve the dispersion uniformity of graphene oxide in ABS plastic, thereby effectively improving the flame retardant properties of ABS plastic shells. AHP is a highly efficient phosphorus-based flame retardant, but it is not easy to be oxidized during thermal decomposition. Phosphine (PH3), a highly toxic gas, is released during the oxidation process. Graphene oxide / aluminum hypophosphite hybrids are added to the ABS plastic shell, and graphene oxide with polyethyleneimine grafted on the surface (PEI-GO) has the ability to inhibit the release of PH3. AHP decomposes into Al2(HPO4)3 and PH3. PH3 is released as a toxic gas, and Al2(HPO4)3 acts as an acid source to catalyze carbonization. The -NH2 of PEI-GO can absorb PH3 through oxidation reaction, forming a -NH-PH2=O structure, reducing the release of PH3, delaying the release time of PH3 and reducing the PH3 concentration. Secondly, under the catalytic action of Al2(HPO4)3, PEI-GO participates in the carbonization process, improving the density and strength of the carbon layer. Carbon fiber (CF) itself has extremely high tensile strength and flexural strength. CF is dispersed into ABS composite materials and gradually forms a mutually overlapping network structure. CF can bear the main external load, and the network structure formed by CF can inhibit the expansion of cracks inside the composite material, which helps the composite material have a greater ability to bear loads, thereby effectively improving the tensile strength and flexural strength of the ABS composite material; the addition of carbon fiber (CF) improves the toughness of the ABS composite material; the mechanical properties advantages of carbon fiber (CF) itself and the network structure formed by carbon fiber (CF) toughen the ABS composite material and inhibit crack growth, thereby effectively improving the impact strength of the ABS composite material; carbon fiber (CF) dispersed in the composite material will form a staggered network structure, which will inhibit the movement of macromolecular chains in the ABS composite material, thereby increasing the difficulty of deformation of the ABS composite material and increasing the thermal deformation temperature of the composite material; the addition of carbon fiber (CF) can effectively improve the comprehensive mechanical and thermal properties of the ABS composite material; In step 1, a polyethyleneimine aqueous solution is added to an (EDC-HCl, NHS) aqueous solution, which effectively provides the prerequisite environmental conditions for the grafting of graphene oxide. Then, a graphene oxide dispersion is dropwise added to the above solution and stirred to effectively graft polyethyleneimine onto the surface of the graphene oxide. Dialysis is mainly used to remove unreacted polyethyleneimine. In step 2, the graphene oxide (PEI-GO) with polyethyleneimine grafted on the surface is added to an aqueous dispersion of aluminum hypophosphite for hybridization. After filtration and freeze-drying, a graphene oxide / aluminum hypophosphite hybrid is obtained. In step 3, the graphene oxide / aluminum hypophosphite hybrid, polycarbonate, acrylonitrile-butadiene-styrene copolymer, and carbon fiber are dried to ensure the purity of the ABS composite material and thereby improve the quality of the ABS composite material. In step 4, the ABS composite material is mixed, melt-extruded, and granulated to make the ABS plastic masterbatch convenient for subsequent injection molding. In step 5, the ABS plastic masterbatch is sent to an injection molding machine for injection molding to obtain a flame-retardant battery ABS plastic shell.

[0026] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A flame-retardant ABS plastic battery shell, characterized by: Ingredients include: Polycarbonate, acrylonitrile-butadiene-styrene copolymer, ethylene-methacrylic acid copolymer, carbon fiber, and graphene oxide / aluminum hypophosphite hybrid.

2. The flame-retardant ABS plastic shell for a battery according to claim 1, characterized in that: The weight ratio of the polycarbonate to the acrylonitrile-butadiene-styrene copolymer is 7:3; the amount of the ethylene-methacrylic acid copolymer is 2.0% to 4.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the amount of the carbon fiber is 14.5% to 15.5% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; and the amount of the graphene oxide / aluminum hypophosphite hybrid is 7.5% to 8.5% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer.

3. The flame-retardant ABS plastic shell for a battery according to claim 2, characterized in that: The raw materials of the graphene oxide / aluminum hypophosphite hybrid include graphene oxide with polyethyleneimine grafted on the surface and aluminum hypophosphite; the weight ratio of the graphene oxide with polyethyleneimine grafted on the surface to the aluminum hypophosphite is 1:95-105.

4. The flame-retardant ABS plastic shell for a battery according to claim 3, characterized in that: The raw materials of the graphene oxide with polyethyleneimine grafted on the surface include polyethyleneimine, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, N-hydroxysuccinimide and graphene oxide.

5. The flame-retardant ABS plastic shell for a battery according to claim 4, characterized in that: The weight ratio of the graphene oxide to polyethylene imine is 1:8-10; the weight ratio of the graphene oxide to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:2-3; and the weight ratio of the graphene oxide to N-hydroxysuccinimide is 1:10-15.

6. The flame-retardant ABS plastic case for a battery according to claim 5, characterized in that: The weight ratio of the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride to N-hydroxysuccinimide is 1:

5.

7. The flame-retardant ABS plastic case for a battery according to claim 5, characterized in that: The amount of the ethylene-methacrylic acid copolymer is 3.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the amount of the carbon fiber is 15.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the amount of the graphene oxide / aluminum hypophosphite hybrid is 8.0% of the total weight of the polycarbonate and the acrylonitrile-butadiene-styrene copolymer; the weight ratio of the graphene oxide with surface grafted polyethyleneimine to aluminum hypophosphite is 1:100; the weight ratio of the graphene oxide to polyethyleneimine is 1:9; the weight ratio of the graphene oxide to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:2; and the weight ratio of the graphene oxide to N-hydroxysuccinimide is 1:

10.

8. A method for preparing a flame-retardant ABS plastic shell for a battery, characterized by: The specific preparation steps are as follows: Step 1: Add a polyethyleneimine aqueous solution to a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride / N-hydroxysuccinimide aqueous solution and mix them. Then, dropwise add a dispersion of graphene oxide to the above solution, stir at room temperature for 24 hours, and dialyze to obtain a dispersion of graphene oxide with polyethyleneimine grafted on its surface. Step 2: adding a dispersion of graphene oxide with polyethyleneimine grafted on its surface to an aqueous dispersion of aluminum hypophosphite, stirring for 15 to 25 minutes, filtering to obtain a precipitate, and freeze-drying the precipitate for 24 hours to obtain a graphene oxide / aluminum hypophosphite hybrid; Step 3: drying the graphene oxide / aluminum hypophosphite hybrid, polycarbonate, acrylonitrile-butadiene-styrene copolymer, and carbon fiber at 75-85° C. for 11-13 hours; Step 4: Add polycarbonate, acrylonitrile-butadiene-styrene copolymer, ethylene-methacrylic acid copolymer, and graphene oxide / aluminum hypophosphite hybrid into a mixer and mix them evenly; add the mixture into a twin-screw extruder for melt blending, then add carbon fiber into the twin-screw extruder, evacuate, extrude the material, cool, dry, and pelletize to obtain flame-retardant battery ABS plastic masterbatch; Step 5: Feed the flame-retardant battery ABS plastic masterbatch into an injection molding machine for injection molding to obtain a flame-retardant battery ABS plastic shell.

9. The method for preparing a flame-retardant ABS plastic shell for a battery according to claim 8, characterized in that: In step 1, the concentration of the polyethyleneimine aqueous solution is 9-11 mg / ml, the concentration of the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride / N-hydroxysuccinimide aqueous solution is 11-13 mg / ml, the concentration of the graphene oxide dispersion is 0.9-1.1 mg / ml, and the stirring speed is 120-180 r / min; in step 2, the concentration of the graphene oxide dispersion with polyethyleneimine grafted on the surface is 0.38-0.42 mg / ml, the concentration of the aqueous dispersion of aluminum hypophosphite is 75-85 mg / ml, and the stirring speed is 600-900 r / min.

10. The method for preparing a flame-retardant ABS plastic shell for a battery according to claim 8, characterized in that: In step 4, the screw speed of the twin-screw extruder is 110-130 r / min, the extrusion temperature is 240-250°C, the material is water-cooled after extrusion, and dried in a drying oven at 55-65°C; in step 5, the injection pressure is 75-85 MPa and the injection temperature is 245-255°C.

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