Composite material, preparation method thereof, and electronic product housing

Abstract

The present application relates to the field of polymer technology and provides a composite material, which comprises the following components in percentage by weight, based on the total weight of the composite material as 100%: 10 to 20 parts of a composite containing carboxylated carbon nanotubes and graphite, 15 to 25 parts of a lightweight filler, 5 to 10 parts of a compatibilizer, 70 to 80 parts of acrylonitrile-butadiene-styrene copolymer, and 20 to 30 parts of polycarbonate. The composite material provided by the present application, by enhancing and modifying acrylonitrile-butadiene-styrene copolymer and polycarbonate with a composite containing carboxylated carbon nanotubes and graphite and a lightweight filler, can greatly improve the mechanical properties and thermal stability of the composite material, the lightweight filler can make the density of the composite material lower while ensuring that the mechanical strength remains basically unchanged, the compatibilizer can enhance compatibility, and thus through the synergistic effect of the above-mentioned components, the composite material of the present application has the advantages of light weight, high strength and good thermal stability.

Description

Technical Field

[0001] The present application belongs to the technical field of polymer materials, and in particular relates to a composite material, a preparation method thereof, and an electronic product housing. Background Art

[0002] With the popularity of electronic products such as LCD TVs, all-in-one conference machines, and smart blackboards, large size and thinness have become the main development trends in the future. However, as the size of electronic products increases, the weight will also increase accordingly, which will bring a lot of inconvenience to the transportation, installation, and storage processes. Since the frame structures of existing large-sized electronic products are mostly made of alloy materials, and a small part uses engineering plastics, if engineering plastics can be used instead of the alloy materials used to make the frame structure, it will undoubtedly reduce the weight of large-sized electronic products to a certain extent and promote the development of thinness. However, although existing plastic products are light in weight, they have low strength and poor thermal stability, which makes it difficult to meet the application requirements of large-sized and thin electronic products.

[0003] Therefore, there is an urgent need to develop a composite material that is lightweight, high in strength and has good thermal stability. Summary of the Invention

[0004] The purpose of this application is to provide a composite material, a preparation method thereof, and an electronic product housing, aiming to solve the problems of low strength and poor thermal stability of existing lightweight composite materials.

[0005] To achieve the above application objectives, the technical solutions adopted in this application are as follows:

[0006] In a first aspect, the present application provides a composite material comprising the following components in parts by weight:

[0007]

[0008]

[0009] The composite containing carboxylated carbon nanotubes and graphite comprises (5-10) parts of carboxylated carbon nanotubes and (5-10) parts of graphite.

[0010] In a second aspect, the present application provides a method for preparing a composite material, comprising the following steps:

[0011] A composite containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, an acrylonitrile-butadiene-styrene copolymer, and polycarbonate are weighed respectively according to a mass ratio of (10-20):(15-25):(5-10):(70-80):(20-30);

[0012] A composite material containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, an acrylonitrile-butadiene-styrene copolymer and polycarbonate are mixed to obtain a mixture;

[0013] The mixed material is melt-extruded and granulated to obtain a composite material.

[0014] In a third aspect, the present application provides an electronic product housing, which is composed of the composite material provided by the present application or the composite material prepared by the preparation method provided by the present application.

[0015] Compared with the prior art, this application has the following beneficial effects:

[0016] The composite material provided in the first aspect of the present application is suitable for electronic product housings, and acrylonitrile-butadiene-styrene copolymer and polycarbonate are reinforced and modified by 10 to 20 parts of a composite material containing carboxylated carbon nanotubes and graphite and 15 to 25 parts of a lightweight filler; wherein the composite material containing carboxylated carbon nanotubes and graphite has the advantages of excellent mechanical properties such as high tensile strength and large elastic modulus of carbon nanotubes and good thermal conductivity of graphite, and is added to acrylonitrile-butadiene-styrene copolymer and polycarbonate to improve the mechanical properties and thermal stability of the composite material such as tensile strength and flexural strength; and the carboxylated carbon nanotubes introduce hydrophilic groups carboxyl groups, which can enhance the compatibility of carbon nanotubes, and graphite can enhance the compatibility of carbon nanotubes by reacting with carboxylated carbon nanotubes. The tube forms a composite containing carboxylated carbon nanotubes and graphite, which can effectively prevent graphite aggregation and enable the composite containing carboxylated carbon nanotubes and graphite to be evenly dispersed in acrylonitrile-butadiene-styrene copolymer and polycarbonate. Therefore, the mechanical properties and thermal stability of the composite material such as tensile strength and flexural strength can be further improved; 15 to 25 parts of lightweight filler can reduce the density of the composite material while ensuring that the mechanical strength remains basically unchanged, making the composite material lighter, and 5 to 10 parts of compatibilizer can increase the dispersibility of acrylonitrile-butadiene-styrene copolymer and polycarbonate, strengthen the compatibility of acrylonitrile-butadiene-styrene copolymer and polycarbonate, and achieve uniform mixing of acrylonitrile-butadiene-styrene copolymer and polycarbonate. Therefore, the composite material provided by the present application, through the synergistic effect of the above-mentioned components, can make the composite material of the present application have the advantages of light weight, high strength and good thermal stability, and has broad application prospects in the electronic products industry.

[0017] The second aspect of the present application provides a method for preparing a composite material, which comprises mixing a compound containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, an acrylonitrile-butadiene-styrene copolymer and a polycarbonate in a mass ratio of (10-20):(15-25):(5-10):(70-80):(20-30) to obtain a mixture, and then melt-extruding and granulating the mixture to obtain a composite material. The preparation method is simple to operate and is suitable for industrial production and application.

[0018] The electronic product housing provided in the third aspect of the present application is composed of the above-mentioned composite material which is light in weight, high in strength and has good thermal stability. Therefore, the electronic product housing also has these excellent properties and can meet the application requirements of electronic product housings. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0020] In this application, the term "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0021] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0022] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0023] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0024] The weights of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the mass described in the examples of this application may be a mass unit known in the chemical industry, such as μg, mg, g, kg, etc.

[0025] The terms "first" and "second" are used solely for descriptive purposes to distinguish objects, such as substances, from one another and should not be understood to indicate or imply relative importance or to implicitly specify the quantity of the technical features being referred to. For example, without departing from the scope of the embodiments of this application, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of such features.

[0026] In a first aspect, an embodiment of the present application provides a composite material, comprising the following components in parts by weight:

[0027]

[0028] The composite containing carboxylated carbon nanotubes and graphite comprises (5-10) parts of carboxylated carbon nanotubes and (5-10) parts of graphite.

[0029] The composite material provided in the embodiment of the present application is suitable for electronic product housings, and acrylonitrile-butadiene-styrene copolymer and polycarbonate are reinforced and modified by 10 to 20 parts of a composite material containing carboxylated carbon nanotubes and graphite and 15 to 25 parts of a lightweight filler; wherein the composite material containing carboxylated carbon nanotubes and graphite has the advantages of excellent mechanical properties such as high tensile strength and large elastic modulus of carbon nanotubes and good thermal conductivity of graphite. When added to acrylonitrile-butadiene-styrene copolymer and polycarbonate, the mechanical properties such as tensile strength and flexural strength and thermal stability of the composite material can be improved; and the carboxylated carbon nanotubes introduce hydrophilic groups such as carboxyl groups, which can enhance the compatibility of carbon nanotubes, and graphite can enhance the compatibility of carbon nanotubes by reacting with the carboxylated carbon nanotubes. The formation of a composite material containing carboxylated carbon nanotubes and graphite can effectively prevent graphite aggregation, so that the composite material containing carboxylated carbon nanotubes and graphite can be evenly dispersed in acrylonitrile-butadiene-styrene copolymer and polycarbonate, thereby further improving the mechanical properties and thermal stability of the composite material such as tensile strength and flexural strength; 15 to 25 parts of lightweight filler can reduce the density of the composite material while ensuring that the mechanical strength remains basically unchanged, making the composite material lighter, and 5 to 10 parts of compatibilizer can increase the dispersibility of acrylonitrile-butadiene-styrene copolymer and polycarbonate, strengthen the compatibility of acrylonitrile-butadiene-styrene copolymer and polycarbonate, and achieve uniform mixing of acrylonitrile-butadiene-styrene copolymer and polycarbonate. Therefore, the composite material provided by the present application, through the synergistic effect of the above-mentioned components, can make the composite material of the present application have the advantages of light weight, high strength and good thermal stability, and has broad application prospects in the electronic products industry.

[0030] Acrylonitrile-butadiene-styrene copolymer is referred to as ABS, hereinafter referred to as ABS, and polycarbonate is referred to as PC, hereinafter referred to as PC. In an embodiment, carboxylated carbon nanotubes are combined with graphite by self-assembly. Carboxylated carbon nanotubes and graphite are combined by self-assembly to form a composite containing carboxylated carbon nanotubes and graphite. Specifically, carboxylated carbon nanotubes are combined with graphite by intermolecular forces such as van der Waals forces, hydrogen bonds, and π-π stacking to form a composite containing carboxylated carbon nanotubes and graphite. Carbon nanotubes have excellent mechanical properties such as high tensile strength and large elastic modulus, and carboxylated carbon nanotubes can improve their compatibility with ABS and PC by introducing hydrophilic groups such as carboxyl groups, so that they can be evenly dispersed in ABS and PC, thereby significantly improving the mechanical properties of the composite material. Graphite has good thermal conductivity. It is combined with carboxylated carbon nanotubes to form a composite by self-assembly, which can effectively prevent graphite aggregation, so that graphite can also be evenly dispersed in acrylonitrile-butadiene-styrene copolymer and polycarbonate, thereby effectively improving the thermal stability of the composite material.

[0031] In the embodiment, the lightweight filler may refer to a filler having a density of 0.1 to 1 g / cm3 The filler, specifically, the lightweight filler includes at least one of hollow glass microspheres and glass fibers. For example, the lightweight filler may be hollow glass microspheres, which have the characteristics of light weight, high strength, and good fluidity. Therefore, the use of lightweight fillers such as hollow glass microspheres can reduce the density and weight of the composite material while also enhancing the mechanical properties of the composite material.

[0032] In an embodiment, the compatibilizer includes at least one of styrene-ethylene-butadiene-styrene copolymer and a maleic anhydride grafted compound. For example, the compatibilizer can be a maleic anhydride grafted compound; specifically, the maleic anhydride grafted compound includes maleic anhydride grafted polyethylene or maleic anhydride grafted polypropylene. The compatibilizer can improve the interfacial interaction between ABS and PC, enhance the compatibility between ABS and PC, and form a uniform and stable blend of ABS and PC, thereby significantly improving the overall performance of the composite material.

[0033] In an embodiment, the composite material includes a compound containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, acrylonitrile-butadiene-styrene copolymer and polycarbonate, and may also include (0.8 to 1.2) parts of an antibacterial agent, (1 to 2) parts of an antioxidant and (1 to 2) parts of a stabilizer. Under the synergistic effect of these additives, the composite material of the present application can further have good mechanical properties and thermal stability.

[0034] In the embodiment, the antimicrobial agent is selected from at least one of chitosan, chitin, and tea polyphenols. These specific antimicrobial agents all have good antimicrobial effects, can impart antimicrobial properties to the composite material, inhibit microbial damage to the composite material, and reduce unnecessary physical or chemical changes. Therefore, the synergistic effect of the antimicrobial agent of this embodiment with the stabilizer and antioxidant can further ensure that the composite material has good mechanical properties and thermal stability.

[0035] In an embodiment, the antioxidant is selected from at least one of a phenolic antioxidant and an aminic antioxidant. For example, the phenolic antioxidant can be selected from antioxidant 1010, antioxidant 1076, antioxidant 3114, etc. The aminic antioxidant can be selected from naphthylamine, diphenylamine, p-phenylenediamine, etc. These specific antioxidants all have good antioxidant effects, play an antioxidant role in the processing of the composite material, so that the composite material can retain the desired performance to the greatest extent after processing, and can also slow down the aging rate of the product. Therefore, through the synergistic effect of the antioxidant of this embodiment with the stabilizer and antibacterial agent, it can further ensure that the composite material has good mechanical properties and thermal stability.

[0036] In an embodiment, the stabilizer is selected from at least one of calcium stearate, calcium ricinoleate, zinc stearate, and zinc ricinoleate. These specific stabilizers have a significant inhibitory effect on the degradation of the composite material, thereby improving the stability of the composite material. Therefore, the synergistic effect of the stabilizer of this embodiment with the antimicrobial agent and antioxidant further ensures that the composite material has good mechanical properties and thermal stability.

[0037] In a specific embodiment, the composite material includes 10 to 20 parts of a compound containing carboxylated carbon nanotubes and graphite, 15 to 25 parts of hollow glass microspheres, 5 to 10 parts of styrene-ethylene-butadiene-styrene copolymer or maleic anhydride graft, 70 to 80 parts of acrylonitrile-butadiene-styrene copolymer, 20 to 30 parts of polycarbonate, (0.8 to 1.2) parts of an antibacterial agent, (1 to 2) parts of an antioxidant and (1 to 2) parts of a stabilizer.

[0038] The composite material provided in the examples of the present application can be prepared by the following method.

[0039] A second aspect of the present invention provides a method for preparing a composite material, comprising the following steps:

[0040] S01: Weigh the composite containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, acrylonitrile-butadiene-styrene copolymer, and polycarbonate in a mass ratio of (10-20):(15-25):(5-10):(70-80):(20-30) respectively;

[0041] S02: mixing a composite containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, an acrylonitrile-butadiene-styrene copolymer, and polycarbonate to obtain a mixture;

[0042] S03: melt-extrude and granulate the mixed material to obtain a composite material.

[0043] The preparation method of the composite material provided in the embodiment of the present application is to prepare the composite material by mixing the raw material components in the formula to obtain a mixture, and then melt-extruding and granulating the mixture. The preparation method is simple to operate and is suitable for industrial production and application.

[0044] In the above step S01, the method for preparing the composite containing carboxylated carbon nanotubes and graphite includes:

[0045] S011: mixing carbon nanotubes and graphite with an acid solution to perform an oxidation reaction to obtain a mixture of carboxylated carbon nanotubes and graphite oxide;

[0046] S012: mixing the mixture with a ferrous salt solution and a reducing agent and performing a reduction reaction to obtain a composite containing carboxylated carbon nanotubes and graphite.

[0047] In step S011, the acid solution comprises concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:(2-3). For example, the acid solution is a mixture of concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:3. The oxidation reaction comprises ultrasonic dispersion at room temperature for 0.5-1 hour. The acid solution acidifies the carbon nanotubes to form carboxylated carbon nanotubes, thereby enhancing the compatibility of the carbon nanotubes. The acid solution also oxidizes the graphite, grafting functional groups such as hydroxyl and carboxyl groups onto the graphite to form graphite oxide, making the graphite hydrophilic and electrostatically repelling the graphite. This allows the graphite to be evenly dispersed in water, paving the way for the next step of reducing the graphite oxide and combining it with the carboxylated carbon nanotubes through self-assembly.

[0048] In the above step S012, the ferrous salt solution can be a ferrous sulfate solution or a ferrous chloride solution, and the reducing agent includes ammonia water and hydrated amine (N2H4·H2O). In an embodiment, the step of mixing the mixture with the ferrous salt solution and the reducing agent and then performing a reduction reaction includes: placing the mixture and the ferrous salt solution in a water bath at 23 to 27°C and stirring for 30 to 40 minutes, heating to 80 to 90°C, and then adding the reducing agent to perform a reduction reaction. By mixing the mixture of carboxylated carbon nanotubes and graphite oxide with the ferrous salt solution and the reducing agent and then performing a reduction reaction, the graphite oxide can be partially reduced to form reduced graphite oxide, thereby improving the hydrophobicity and conjugated structure of the graphite, promoting π-π stacking, and allowing the graphite to combine with the carboxylated carbon nanotubes through self-assembly to form a composite containing carboxylated carbon nanotubes and graphite, which can effectively avoid graphite aggregation, so that the graphite can also be evenly distributed in ABS and PC, thereby significantly improving the heat deformation temperature of the composite material and improving thermal stability.

[0049] In the above-mentioned step S02, the step of mixing the composite containing carboxylated carbon nanotubes and graphite, the lightweight filler, the compatibilizer, the acrylonitrile-butadiene-styrene copolymer and the polycarbonate includes: placing the compatibilizer and the acrylonitrile-butadiene-styrene copolymer in a mixer with an operating temperature of 180 to 240° C. and a rotation speed of 1000 to 1500 r / min and mixing them for 0.8 to 1.5 hours, then adding the polycarbonate and continuing to mix for 0.8 to 1.5 hours, and then adding the composite containing carboxylated carbon nanotubes and graphite and the lightweight filler and mixing them evenly.

[0050] In the above step S03, the step of melt-extruding and granulating the mixture includes: melt-extruding and granulating the mixture through a twin-screw extruder at a working temperature of 180° C. to 245° C. and a twin-screw speed of 250 to 350 r / min to obtain a composite material.

[0051] In an embodiment, the main barrel of a twin screw extruder is divided into 190-210°C, 190-210°C, 200-220°C, 200-210°C, 200-210°C, 200-210°C, 200-210°C, 200-210°C, 200-210°C and 200-220°C ten sections of control from the feed port to the die outlet, and the temperature in the main barrel of the twin screw extruder is controlled in sections so that each raw material component is heated evenly in each position and stage in the barrel, so that each raw material component is mixed more evenly. In a specific embodiment, the main barrel of a twin screw extruder is divided into 200°C, 200°C, 210°C, 205°C, 205°C, 205°C, 205°C, 205°C, 205°C, 210°C ten sections of control from the feed port to the die outlet.

[0052] A third aspect of the embodiments of the present application provides an electronic product housing, which is composed of the composite material provided in the present application or the composite material prepared by the preparation method provided in the present application.

[0053] The electronic product housing provided in the embodiment of the present application is composed of the above-mentioned composite material that is light in weight, strong in strength and has good heat dissipation performance. Therefore, the electronic product housing also has these excellent properties and can meet the application requirements of electronic product housings.

[0054] The following describes the details in conjunction with specific embodiments.

[0055] Example 1

[0056] This embodiment provides a composite material and a preparation method thereof.

[0057] A composite material comprising the following components in percentage by weight:

[0058]

[0059] The composite containing carboxylated carbon nanotubes and graphite includes 5 parts of carboxylated carbon nanotubes and 5 parts of graphite.

[0060] The preparation method of the composite material comprises the following steps:

[0061] S11: Preparation of a composite containing carboxylated carbon nanotubes and graphite:

[0062] Carbon nanotubes and graphite were weighed in a mass ratio of 5:5, placed in a mixture of concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:3, and ultrasonically dispersed for 0.5 to 1 hour to obtain a mixture of carboxylated carbon nanotubes and graphite oxide;

[0063] The FeCl2 solution is added to a mixture of carboxylated carbon nanotubes and graphite oxide, stirred in a water bath at 25°C for 30-40 minutes, then heated to 80-90°C, and appropriate amounts of NH3·H2O and N2H4·H2O are added and mixed evenly, followed by drying to obtain a composite containing carboxylated carbon nanotubes and graphite;

[0064] S12: weighing a composite containing carboxylated carbon nanotubes and graphite, hollow glass microspheres, maleic anhydride grafted polyethylene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, chitosan, diphenylamine, and calcium stearate in a mass ratio of 10:15:5:70:30:0.8:1:1;

[0065] S13: Place acrylonitrile-butadiene-styrene copolymer and maleic anhydride grafted polyethylene in a high-speed mixer at a working temperature of 200°C and a rotation speed of 1000-1500 r / min and mix them for 1 hour, then add polycarbonate and continue mixing for 1 hour, then add hollow glass microbeads, a composite containing carboxylated carbon nanotubes and graphite, chitosan, diphenylamine and calcium stearate in sequence and mix well, finally add them to a twin-screw extruder for melt extrusion and granulation to obtain a composite material.

[0066] Example 2

[0067] This embodiment provides a composite material and a preparation method thereof.

[0068] A composite material comprising the following components in percentage by weight:

[0069]

[0070] The composite containing carboxylated carbon nanotubes and graphite includes 10 parts of carboxylated carbon nanotubes and 7 parts of graphite.

[0071] The preparation method of the composite material comprises the following steps:

[0072] S21: Preparation of a composite containing carboxylated carbon nanotubes and graphite:

[0073] Carbon nanotubes and graphite were weighed in a mass ratio of 10:7, placed in a mixture of concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:3, and ultrasonically dispersed for 0.5 to 1 hour to obtain a mixture of carboxylated carbon nanotubes and graphite oxide;

[0074] The FeCl2 solution is added to a mixture of carboxylated carbon nanotubes and graphite oxide, stirred in a water bath at 25°C for 30-40 minutes, then heated to 80-90°C, and appropriate amounts of NH3·H2O and N2H4·H2O are added and mixed evenly, followed by drying to obtain a composite containing carboxylated carbon nanotubes and graphite;

[0075] S22: weighing a composite containing carboxylated carbon nanotubes and graphite, hollow glass microspheres, maleic anhydride grafted polyethylene, acrylonitrile-butadiene-styrene copolymer, and polycarbonate in a mass ratio of 17:20:8:75:25, respectively;

[0076] S23: Place acrylonitrile-butadiene-styrene copolymer and maleic anhydride grafted polyethylene in a high-speed mixer at a working temperature of 200°C and a rotation speed of 1000-1500 r / min and mix them for 1 hour, then add polycarbonate and continue mixing for 1 hour, then add hollow glass microbeads and a composite containing carboxylated carbon nanotubes and graphite in sequence and mix evenly, finally add them to a twin-screw extruder for melt extrusion and granulation to obtain a composite material.

[0077] Example 3

[0078] This embodiment provides a composite material and a preparation method thereof.

[0079] A composite material comprising the following components in percentage by weight:

[0080]

[0081] The composite containing carboxylated carbon nanotubes and graphite includes 10 parts of carboxylated carbon nanotubes and 10 parts of graphite.

[0082] The preparation method of the composite material of this embodiment specifically refers to the steps of Example 1, and the difference from Example 1 is that in step S32, the composite material containing carboxylated carbon nanotubes and graphite, hollow glass microspheres, maleic anhydride grafted polyethylene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, chitosan, diphenylamine and calcium stearate are weighed respectively according to a mass ratio of 20:25:10:80:20:1.2:2:2.

[0083] Example 4

[0084] This embodiment provides a composite material and a preparation method thereof.

[0085] A composite material comprising the following components in percentage by weight:

[0086]

[0087] The composite containing carboxylated carbon nanotubes and graphite includes 10 parts of carboxylated carbon nanotubes and 7 parts of graphite.

[0088] The preparation method of the composite material comprises the following steps:

[0089] S41: Preparation of a composite containing carboxylated carbon nanotubes and graphite:

[0090] Carbon nanotubes and graphite were weighed in a mass ratio of 5:5, placed in a mixture of concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:3, and ultrasonically dispersed for 0.5 to 1 hour to obtain a mixture of carboxylated carbon nanotubes and graphite oxide;

[0091] The FeCl2 solution is added to a mixture of carboxylated carbon nanotubes and graphite oxide, stirred in a water bath at 25°C for 30-40 minutes, then heated to 80-90°C, and appropriate amounts of NH3·H2O and N2H4·H2O are added and mixed evenly, followed by drying to obtain a composite containing carboxylated carbon nanotubes and graphite;

[0092] S42: weighing a composite containing carboxylated carbon nanotubes and graphite, hollow glass microspheres, maleic anhydride grafted polyethylene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, chitin, antioxidant 3114, and calcium ricinoleate in a mass ratio of 17:20:8:75:25:1:1.5:1.5, respectively;

[0093] S43: Place acrylonitrile-butadiene-styrene copolymer and maleic anhydride grafted polyethylene in a high-speed mixer at a working temperature of 200°C and a rotation speed of 1000-1500 r / min and mix them for 1 hour, then add polycarbonate and continue mixing for 1 hour, then add hollow glass microspheres, a composite containing carboxylated carbon nanotubes and graphite, chitin, antioxidant 3114 and calcium ricinoleate in sequence and mix well, finally add them to a twin-screw extruder for melt extrusion and granulation to obtain a composite material.

[0094] Comparative Example 1

[0095] This comparative example provides a commercially available ABS / PC material.

[0096] Comparative Example 2

[0097] This embodiment provides a composite material and a preparation method thereof.

[0098] A composite material comprising the following components in percentage by weight:

[0099]

[0100] The preparation method of the composite material comprises the following steps:

[0101] S1: hollow glass microspheres, maleic anhydride grafted polyethylene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, chitin, antioxidant 3114, and calcium ricinoleate were weighed in a mass ratio of 20:8:75:25:1:1.5:1.5 respectively;

[0102] S2: Place acrylonitrile-butadiene-styrene copolymer and maleic anhydride grafted polyethylene in a high-speed mixer at a working temperature of 200°C and a rotation speed of 1000-1500 r / min and mix them for 1 hour. Then add polycarbonate and continue mixing for 1 hour. Then, add hollow glass microspheres, chitosan, diphenylamine and calcium stearate in sequence and mix well. Finally, add them to a twin-screw extruder for melt extrusion and granulation to obtain a composite material.

[0103] Comparative Example 3

[0104] This embodiment provides a composite material and a preparation method thereof.

[0105] A composite material comprising the following components in percentage by weight:

[0106]

[0107] The preparation method of the composite material comprises the following steps:

[0108] S1: Weigh carbon nanotubes, graphite, maleic anhydride grafted polyethylene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, chitin, antioxidant 3114, and calcium ricinoleate in a mass ratio of 10:7:8:75:25:1:1.5:1.5 respectively;

[0109] S2: Place acrylonitrile-butadiene-styrene copolymer and maleic anhydride grafted polyethylene in a high-speed mixer at a working temperature of 200°C and a rotation speed of 1000-1500 r / min and mix them for 1 hour. Then add polycarbonate and continue mixing for 1 hour. Then, add carbon nanotubes, graphite, chitosan, diphenylamine and calcium stearate in sequence and mix well. Finally, add them to a twin-screw extruder for melt extrusion and granulation to obtain a composite material.

[0110] Related performance test analysis:

[0111] In order to verify the progressiveness of the composite materials of the examples of the present application, performance tests were carried out on the examples of the present application and the comparative examples.

[0112] The products prepared in Examples 1-4 and Comparative Examples 1-3 were pelletized and batch mixed, then injection molded into standard bars using a plastic injection molding machine at a molding temperature of 210°C. The molded bars were immediately placed in a glass desiccator and left at room temperature for at least 24 hours before mechanical property testing. The test results are shown in Table 1 below.

[0113] Performance test methods:

[0114] Tensile strength is determined in accordance with ASTM D638 Test Method for Tensile Properties of Plastics;

[0115] Bending strength is in accordance with the method of "ASTM_D790-03 Standard Test Method for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials";

[0116] The heat deformation temperature is in accordance with the method of "GB / T1634-2004 Test method for heat deformation temperature of plastics under bending load".

[0117] Table 1

[0118] Tensile strength (Mpa) Bending strength (Mpa) Heat deformation temperature Example 1 89 110 129℃ Example 2 91 117 137℃ Example 3 94 125 141℃ Example 4 92 119 138℃ Comparative Example 1 56 76 97℃ Comparative Example 2 65 81 100℃ Comparative Example 3 72 98 119℃

[0119] From the above test results, it can be seen that the tensile strength, flexural strength and heat deformation temperature of the standard specimens made of the composite materials of Examples 1 to 4 are significantly higher than the mechanical properties of the standard specimens made of the commercially available ABS / PC material of Comparative Example 1; the tensile strength, flexural strength and heat deformation temperature of the standard specimens made of the composite material of Example 2 are significantly higher than the tensile strength, flexural strength and heat deformation temperature of the standard specimens made of the composite material of Comparative Example 2 without the composite material of the composite material of the composite material of Comparative Example 2, and are also significantly higher than the tensile strength, flexural strength and heat deformation temperature of the standard specimens made of the composite material of Comparative Example 3 with the addition of carbon nanotubes and graphite, indicating that the acidification of carbon nanotubes by mixed acid to form carboxylated carbon nanotubes can enhance the mechanical properties of nanotubes. The compatibility of carbon nanotubes makes it easier to mix evenly in ABS and PC, which can significantly improve the tensile strength, flexural strength and other mechanical properties of the composite material; the mixed acid oxidizes the graphite, grafts functional groups such as hydroxyl and carboxyl groups on the graphite, forms graphite oxide, makes the graphite hydrophilic, and is conducive to the full and uniform dispersion of the graphite. Then, by reducing the graphite oxide to form reduced graphite oxide, the hydrophobicity and conjugated structure of the graphite can be improved, and π-π stacking is promoted, so that the graphite is combined with the carboxylated carbon nanotubes through self-assembly to form a composite containing carboxylated carbon nanotubes and graphite, which can effectively avoid graphite aggregation, so that the graphite can also be evenly distributed in ABS and PC, thereby significantly improving the heat deformation temperature of the composite material and improving thermal stability. The composite materials of Examples 1 to 4 above have excellent mechanical properties such as tensile strength and flexural strength and thermal stability.

[0120] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A composite material, characterized in that: The composition comprises the following components in parts by weight: 10-20 parts of a composite containing carboxylated carbon nanotubes and graphite 15~25 parts of light filler 5~10 parts of compatibilizer 70-80 parts of acrylonitrile-butadiene-styrene copolymer 20-30 parts of polycarbonate; The composite containing carboxylated carbon nanotubes and graphite comprises 5 to 10 parts of carboxylated carbon nanotubes and 5 to 10 parts of graphite; the carboxylated carbon nanotubes are combined with the graphite by self-assembly; the lightweight filler comprises at least one of hollow glass microspheres and glass fibers; and / or the compatibilizer comprises at least one of styrene-ethylene-butadiene-styrene copolymer and maleic anhydride grafted compound; The preparation method of the composite containing carboxylated carbon nanotubes and graphite comprises: The carbon nanotubes and graphite are mixed with an acid solution for oxidation reaction to obtain a mixture of carboxylated carbon nanotubes and graphite oxide; wherein the acid solution comprises concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1: (2-3); The mixture is mixed with a ferrous salt solution and a reducing agent and then subjected to a reduction reaction to obtain a composite containing carboxylated carbon nanotubes and graphite; wherein the ferrous salt solution is a ferrous sulfate solution or a ferrous chloride solution, and the reducing agent includes ammonia water and hydrated amine.

2. The composite material according to claim 1, wherein The composite material further comprises: 0.8~1.2 parts of antibacterial agent 1~2 parts antioxidant 1~2 parts of stabilizer.

3. The composite material according to claim 2, wherein The antibacterial agent is selected from at least one of chitosan, chitin, and tea polyphenols; and / or The antioxidant is selected from at least one of phenolic antioxidants and amine antioxidants; and / or The stabilizer is selected from at least one of calcium stearate, calcium ricinoleate, zinc stearate and zinc ricinoleate.

4. A method for preparing the composite material according to claim 1, characterized in that: The following steps are involved: The composite containing carboxylated carbon nanotubes and graphite, a lightweight filler, a compatibilizer, acrylonitrile-butadiene-styrene copolymer, and polycarbonate were weighed in a mass ratio of (10-20):(15-25):(5-10):(70-80):(20-30). Mixing the composite containing carboxylated carbon nanotubes and graphite, the lightweight filler, the compatibilizer, the acrylonitrile-butadiene-styrene copolymer and the polycarbonate to obtain a mixture; Melting, extruding and granulating the mixture to obtain a composite material; The preparation method of the composite containing carboxylated carbon nanotubes and graphite comprises: Mixing carbon nanotubes and graphite with an acid solution for oxidation reaction to obtain a mixture of carboxylated carbon nanotubes and graphite oxide; wherein the acid solution comprises concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:(2-3); The mixture is mixed with a ferrous salt solution and a reducing agent and then subjected to a reduction reaction to obtain a composite containing carboxylated carbon nanotubes and graphite; wherein the ferrous salt solution is a ferrous sulfate solution or a ferrous chloride solution, and the reducing agent includes ammonia water and hydrated amine.

5. The preparation method according to claim 4, wherein The step of mixing the mixture with a ferrous salt solution and a reducing agent and then performing a reduction reaction comprises: placing the mixture and the ferrous salt solution in a water bath at 23-27° C. and stirring for 30-40 minutes, heating the water bath to 80-90° C., and then adding the reducing agent to perform a reduction reaction.

6. The preparation method according to claim 4 or claim 5, characterized in that The step of mixing the composite containing carboxylated carbon nanotubes and graphite, the lightweight filler, the compatibilizer, the acrylonitrile-butadiene-styrene copolymer and the polycarbonate comprises: The compatibilizer and the acrylonitrile-butadiene-styrene copolymer are placed in a mixer with a working temperature of 180-240° C. and a rotation speed of 1000-1500 r / min and mixed for 0.8-1.5 hours, and then the polycarbonate is added and mixed for another 0.8-1.5 hours. Finally, the composite containing carboxylated carbon nanotubes and graphite and the lightweight filler are added and mixed evenly.

7. An electronic product housing, characterized in that: The electronic product housing is composed of the composite material according to any one of claims 1 to 3 or the composite material prepared by the preparation method according to any one of claims 4 to 6.

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