Plastic, housing and preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of plastics, and provides a plastic, a housing and a preparation method therefor and a use thereof. The plastic comprises the following components in parts by weight: 60-80 parts of a plastic matrix, 10-20 parts of a reinforcing fiber, 5-10 parts of a conductive filler, 5-10 parts of a magnetic filler, and 0.5-2 parts of a coupling agent. The conductive filler and the magnetic filler are added into the plastic of the present invention, and the plastic can achieve broadband electromagnetic shielding performance by means of the synergistic effect of the dual mechanisms of reflecting high-frequency electromagnetic waves and absorbing low-frequency magnetic fields by means of reflection loss and hysteresis loss, respectively. Therefore, the present invention can mitigate the problem of a weak electromagnetic shielding effect existing in a plastic-based electrical appliance housing.

Description

Plastics, shells, their preparation methods and applications

[0001] This application claims priority to Chinese Patent Application No. 202411494486.9, filed on October 24, 2024, entitled "Plastics, Shells and Preparation Methods Thereof and Applications Thereof", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to the field of plastics technology, and in particular to a plastic, a shell, a method for preparing the same, and its applications. Background Technology

[0003] With the rapid development of new energy vehicle technology, the electrical housing, as a crucial component protecting internal components, providing electromagnetic shielding, and dissipating heat, directly impacts the overall vehicle performance and user experience. While aluminum alloy housings possess excellent mechanical properties and electromagnetic shielding, their high density, high energy consumption, and noise issues are becoming increasingly prominent, failing to meet the urgent demands of the new energy vehicle industry for lightweighting, low carbon emissions, and enhanced comfort. Compared to traditional metal housings, plastic housings have lower density, contributing to vehicle lightweighting goals, thereby reducing energy consumption and improving range. Therefore, plastic housings demonstrate significant advantages in the new energy vehicle field. However, plastic itself lacks electromagnetic shielding capabilities; electronic radiation can cause electronic system malfunctions, disrupt equipment operation, and result in economic losses.

[0004] Conventional techniques involve depositing a layer of metal or spraying a conductive coating onto the surface of a plastic substrate. The plastic substrate serves as a support layer, while the metal or conductive coating primarily functions to prevent electromagnetic interference.

[0005] However, this technology has problems such as the metal coating being susceptible to corrosion and the conductive coating being prone to peeling off, which weakens the electromagnetic shielding effect of the appliance casing. Summary of the Invention

[0006] In view of the above problems, the present invention proposes a plastic, a housing, a method for preparing the same, and its application, aiming to improve the problem of weak electromagnetic shielding effect of plastic-based electrical housings.

[0007] In a first aspect, the present invention provides a plastic comprising the following components in parts by weight:

[0008] 60-80 parts plastic matrix, 10-20 parts reinforcing fiber, 5-10 parts conductive filler, 5-10 parts magnetic filler, and 0.5-2 parts coupling agent.

[0009] In one embodiment, the plastic matrix is ​​selected from at least one of polyphenylene sulfide and polyphthalamide.

[0010] In one embodiment, the reinforcing fiber is selected from at least one of carbon fiber and glass fiber.

[0011] In one embodiment, the conductive filler and the magnetic filler are in the form of flakes or granules.

[0012] In one embodiment, the particle size of the sheet-like conductive filler and the magnetic filler is 30 μm-80 μm; and / or, the particle size of the particulate conductive filler and the magnetic filler is 500 nm-10 μm.

[0013] In one embodiment, the conductive filler is a carbon-based conductive filler.

[0014] In one embodiment, the conductive filler is selected from at least one of graphene, carbon nanotubes, expanded graphite, graphite sheets, nickel-plated graphite, and carbon black.

[0015] In one embodiment, the magnetic filler is selected from at least one of iron-based magnetic fillers and nickel-based magnetic fillers.

[0016] In one embodiment, the magnetic filler is selected from at least one of iron-nickel alloy, iron-cobalt alloy, ferrite, and carbonyl iron.

[0017] In one embodiment, the coupling agent is selected from at least one of silane coupling agents and titanate coupling agents.

[0018] In a second aspect, the present invention provides a housing made of any of the aforementioned plastics.

[0019] Thirdly, the present invention provides a method for preparing a shell, which involves mixing 60-80 parts by weight of a plastic matrix, 10-20 parts by weight of reinforcing fibers, 5-10 parts by weight of conductive filler, 5-10 parts by weight of magnetic filler and 0.5-2 parts by weight of coupling agent, followed by extrusion granulation and injection molding.

[0020] In one embodiment, the parameters of the extrusion granulation satisfy at least one of the following conditions:

[0021] The barrel temperature is 300℃-340℃; the screw speed is 400r / min-500r / min; and / or,

[0022] The injection molding parameters satisfy at least one of the following conditions:

[0023] The barrel temperature is 300℃-350℃; the nozzle temperature is 320℃-330℃; the mold temperature is 120℃-150℃; and the injection pressure is 80MPa-130MPa.

[0024] Fourthly, the present invention provides the application of the above-described housing or the housing prepared by any of the above-described methods in electrical appliances.

[0025] The plastic of this invention comprises conductive filler and magnetic filler. The conductive filler increases the surface conductivity of the plastic, thereby increasing the reflection of electromagnetic waves on the material surface and achieving the effect of shielding high-frequency electromagnetic waves. The magnetic filler absorbs low-frequency magnetic fields through hysteresis loss. The combination of conductive and magnetic fillers forms an effective conductive network and magnetic circuit, enabling the plastic to achieve wide-band electromagnetic shielding performance through the synergistic effect of the dual mechanism (conductivity and magnetism) of reflecting high-frequency electromagnetic waves and absorbing low-frequency magnetic fields. Therefore, this invention can improve the problem of weak electromagnetic shielding effect in plastic-based electrical appliance housings. Detailed Implementation

[0026] The following embodiments are only used to illustrate the technical solutions of the present invention more clearly, and are therefore only examples and should not be used to limit the scope of protection of the present invention.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having”, and any variations thereof, in the specification and claims of this invention are intended to cover non-exclusive inclusion.

[0028] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0029] In the description of the embodiments of this invention, the term "and / or" is merely a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship. The term "at least one" refers to one or more.

[0030] To achieve the requirements of lightweight design and electromagnetic shielding, conventional techniques involve depositing a layer of metal or spraying a conductive coating onto the surface of a plastic substrate. The plastic substrate serves as the support layer, while the metal or conductive coating primarily functions to block electromagnetic interference. However, this technique suffers from problems such as the metal coating's susceptibility to corrosion and the conductive coating's tendency to peel off, thus weakening the electromagnetic shielding effect of the appliance's casing.

[0031] In view of the above problems, the present invention provides a plastic comprising the following components in parts by weight: 60-80 parts of plastic matrix, 10-20 parts of reinforcing fiber, 5-10 parts of conductive filler, 5-10 parts of magnetic filler, and 0.5-2 parts of coupling agent.

[0032] The plastic matrix, as the main component, forms the supporting structure. Reinforcing fibers, a material with high strength and high modulus, can improve the mechanical strength of products formed from this plastic.

[0033] Conductive fillers are substances that can improve the conductivity of materials. This invention adds conductive fillers to a plastic matrix, which can improve the surface conductivity of the plastic, increase the reflection loss of electromagnetic waves on the material surface, and achieve the effect of shielding high-frequency electromagnetic waves.

[0034] Magnetic filler refers to a filling material with magnetic properties. Low-frequency magnetic fields, due to their low frequency and short wavelength, easily penetrate materials and cannot be lost through reflection on the surface of the shielding body. This invention incorporates magnetic filler into a plastic matrix, which can absorb low-frequency magnetic fields through hysteresis loss.

[0035] The addition of coupling agents can enhance the compatibility between conductive and magnetic fillers and the plastic matrix, and facilitate the uniform distribution of conductive and magnetic fillers in the plastic matrix.

[0036] This invention combines magnetic and conductive fillers to form an effective conductive network and magnetic circuit. This allows the plastic to achieve broadband electromagnetic shielding performance through the synergistic effect of a dual mechanism (conductivity and magnetism) that reflects high-frequency electromagnetic waves and guides low-frequency magnetic fields. Therefore, the plastic used in this invention, when used to make electrical appliance housings, possesses strong broadband electromagnetic shielding capabilities, thus improving the problem of weak electromagnetic shielding effects in plastic-based electrical appliance housings.

[0037] According to some embodiments of the present invention, the plastic matrix is ​​selected from at least one of polyphenylene sulfide and polyphthalamide.

[0038] Polyphenylene sulfide (PPS) has a molecular structure composed of alternating benzene rings and sulfur atoms, exhibiting high regularity and crystallinity. The presence of numerous aromatic rings and thioether bonds in the PPS molecular chain contributes to its excellent heat resistance, chemical corrosion resistance, and mechanical properties. Furthermore, PPS also possesses good electrical insulation properties, high-temperature resistance, and flame retardant properties.

[0039] Polyphthalamide (PPA) has a rigid aromatic ring and amide bond in its molecular structure. The aromatic ring provides high strength and high heat resistance, while the amide bond provides good mechanical properties and chemical stability. Polyphthalamide also has good electrical insulation properties.

[0040] Polyphenylene sulfide and polyphthalamide, as high-performance plastics, have low density and good processing properties, which helps them to be used in lightweight housing designs.

[0041] According to some embodiments of the present invention, the reinforcing fiber is selected from at least one of carbon fiber and glass fiber.

[0042] Carbon fiber is a high-strength, high-modulus fiber material with a carbon content of over 90%. It possesses excellent electrical conductivity, mechanical strength, and chemical stability, and can simultaneously enhance the mechanical and electrical properties of plastics. The length of the carbon fiber is not specifically limited in this embodiment of the invention; however, short fibers with a length between 0.5 mm and 6 mm can be used as reinforcing materials, for example.

[0043] Glass fiber has high tensile strength and elastic modulus, which can significantly improve the strength and stiffness of materials. The length of glass fiber can be selected as 3mm, 6mm or 12mm.

[0044] Using carbon fiber and / or glass fiber as reinforcing materials allows the plastic shell to meet the requirements of lightweight and high strength.

[0045] According to some embodiments of the present invention, the conductive filler and the magnetic filler have a morphology of flakes or granules.

[0046] When forming conductive pathways, sheet-like conductive fillers exhibit relatively low resistance due to the line or surface contact between the fillers, enabling more efficient current conduction. Sheet-like magnetic fillers can be tightly packed within the plastic matrix, achieving high filler density and facilitating the formation of more magnetic pathways, thereby improving the magnetic permeability of the plastic. Particulate conductive and magnetic fillers are more easily dispersed in the matrix, contributing to improved consistency in the plastic.

[0047] According to some embodiments of the present invention, the particle size of the sheet-like conductive filler and the magnetic filler is 30 μm-80 μm; and / or, the particle size of the particulate conductive filler and the magnetic filler is 500 nm-10 μm.

[0048] Micron-sized sheet-like conductive fillers help improve conductivity, while micron-sized sheet-like magnetic fillers help improve magnetic permeability.

[0049] According to some embodiments of the present invention, the conductive filler is a carbon-based conductive filler.

[0050] Carbon-based conductive fillers are a class of filler materials with conductive properties, primarily composed of carbon. They have a low density, which helps reduce the weight of the plastic casing while maintaining conductivity.

[0051] According to some embodiments of the present invention, the conductive filler is selected from at least one of graphene, carbon nanotubes, expanded graphite, graphite sheets, nickel-plated graphite, and carbon black.

[0052] Graphene is a two-dimensional sheet-like material composed of a single layer of carbon atoms, possessing extremely high specific surface area, excellent electrical and thermal conductivity. Carbon nanotubes are tubular structures with nanoscale dimensions; due to their nanoscale effect, they can form highly efficient conductive networks even with relatively low filler content. Expanded graphite is produced by mixing natural flake graphite with strong acids (such as concentrated sulfuric acid) and strong oxidants (such as potassium permanganate), undergoing an intercalation reaction under certain conditions, and then rapidly decomposing and vaporizing the intercalating agent through high-temperature heating. The resulting gas pressure causes the graphite layer to expand along the C-axis, forming a worm-like graphite structure with a large specific surface area and good electrical conductivity. Graphite flakes refer to sheet-like graphite, exhibiting excellent electrical and thermal conductivity. Nickel-plated graphite is a graphite-reinforced material; by chemically plating nickel onto graphite powder, the electrical conductivity of graphite is significantly improved, and different electrical properties can be obtained by adjusting the amount of nickel plating on the graphite surface. Carbon black is a black powdery substance formed by the incomplete combustion or pyrolysis of hydrocarbons. It has a high specific surface area and abundant pore structure, which allows carbon black to fully contact the matrix material and form a good conductive network.

[0053] According to some embodiments of the present invention, the magnetic filler is selected from at least one of iron-based magnetic fillers and nickel-based magnetic fillers.

[0054] Ferrous magnetic fillers refer to magnetic fillers whose main component is iron, including but not limited to iron powder, magnetite, ferrite, and iron-containing alloys. Nickel-based magnetic fillers refer to magnetic fillers whose main component is nickel, including but not limited to nickel powder and nickel-containing alloys.

[0055] According to some embodiments of the present invention, the magnetic filler is selected from at least one of iron-nickel alloy, iron-cobalt alloy, ferrite, and carbonyl iron.

[0056] Iron-nickel alloys are alloys composed of two metallic elements, nickel and iron. Iron-cobalt alloys are alloys composed of two metallic elements, iron and cobalt. Different magnetic fillers with varying properties can be obtained by adjusting the component ratios of iron-nickel and iron-cobalt alloys. Ferrites are a class of ceramic-like magnetic materials composed of iron oxides and other metal oxides. Common types include manganese-zinc ferrite and nickel-zinc ferrite. Ferrites can absorb and attenuate electromagnetic waves, reducing electromagnetic interference. Carbonyl iron refers to pentacarbonyl iron, an inorganic compound. Carbonyl iron powder possesses excellent magnetic properties.

[0057] According to some embodiments of the present invention, the coupling agent is selected from at least one of silane coupling agents and titanate coupling agents.

[0058] Silane coupling agents are low-molecular-weight organosilicon compounds containing organic functional groups and hydrolyzable groups. They not only improve the compatibility of conductive fillers and magnetic fillers with the matrix, but also enable a tight bond between reinforcing fibers and the matrix, thereby improving the mechanical properties of plastics. Their general formula is R-Si-X3, where R- represents oxygen, mercapto, vinyl, epoxy, amide, aminopropyl, etc., and X- represents a hydrolyzable alkoxy group, such as halogen, alkoxy, acyl, etc.

[0059] The alkoxy groups in titanate coupling agents can chemically couple with trace amounts of carboxyl or hydroxyl groups adsorbed on the filler surface. The organic framework in the molecule can bend and entangle with the plastic matrix, thereby improving the compatibility between organic and inorganic materials. Its general formula is RO-Ti(OX-RY)3, where RO- represents an alkoxy group, OX- can be a carboxyl group, alkoxy group, sulfonic acid group, phosphorus group, etc., R- is a long-chain alkane group, and Y- is a hydroxyl, amino, epoxy group, or a group containing a double bond.

[0060] According to some embodiments of the present invention, the present invention also provides a housing made of any of the plastics described above.

[0061] According to some embodiments of the present invention, the present invention also provides a method for preparing a shell, wherein 60-80 parts by weight of a plastic matrix, 10-20 parts by weight of reinforcing fibers, 5-10 parts by weight of conductive filler, 5-10 parts by weight of magnetic filler and 0.5-2 parts by weight of coupling agent are mixed and then extruded, granulated and injection molded.

[0062] Extrusion granulation can uniformly mix the components, ensuring the consistency of the shell material composition. During the extrusion process, the material is subjected to high temperature and shear force, which can modify the material, thereby enhancing the shell's strength and rigidity. Furthermore, extrusion granulation enables continuous production, helping to improve production efficiency. Extrusion granulation can be achieved using a screw extruder.

[0063] Injection molding is a process in which plastic masterbatch is heated and melted into a liquid state, and then injected into a closed mold cavity under certain pressure. After cooling and solidification, a plastic shell is obtained. Injection molding has the advantages of high dimensional accuracy, the ability to manufacture products with complex shapes, and high production efficiency.

[0064] According to some embodiments of this application, the parameters of extrusion granulation satisfy at least one of the following conditions: barrel temperature is 300℃-340℃; screw speed is 400r / min-500r / min; and / or, the parameters of injection molding satisfy at least one of the following conditions: barrel temperature is 300℃-350℃; nozzle temperature is 320℃-330℃; mold temperature is 120℃-150℃; injection pressure is 80MPa-130MPa.

[0065] According to some embodiments of the present invention, the present invention provides the application of the above-described housing or the housing prepared by any of the above-described methods in electrical appliances. That is, the housing of the present invention can be used as an electrical appliance housing; for example, it can be used as an electrical appliance housing for new energy vehicles, and can meet the requirements of electromagnetic shielding.

[0066] The present invention will now be described through specific embodiments.

[0067] Example 1

[0068] An electrical appliance housing, the material of which comprises the following components in parts by weight:

[0069] The composition includes 70 parts polyphenylene sulfide, 15 parts carbon fiber, 5 parts nickel-plated graphite, 5 parts carbonyl iron powder, and 0.5 parts heat-resistant silane coupling agent Y-5475. The nickel-plated graphite and carbonyl iron powder are both flake-shaped with a particle size of 30 μm.

[0070] The method for preparing the casing of an electrical appliance includes the following steps:

[0071] Polyphenylene sulfide, carbon fiber, nickel-plated graphite, carbonyl iron powder, and heat-resistant silane coupling agent Y-5475 were added to a twin-screw extruder and extruded to granulate plastic masterbatch. The parameters for extrusion molding were: barrel temperature of 320℃ and screw speed of 500r / min.

[0072] The plastic masterbatch is heated and melted and injected into the corresponding shell mold for injection molding. The injection molding parameters are: barrel temperature 350℃, nozzle temperature 320℃, mold temperature 130℃, and injection pressure 100MPa. After cooling and solidification, it is ready for use.

[0073] Example 2

[0074] An electrical appliance housing, the material of which comprises the following components in parts by weight:

[0075] The composition includes 70 parts polyphenylene sulfide, 15 parts carbon fiber, 5 parts nickel-plated graphite, 5 parts carbonyl iron powder, and 2 parts heat-resistant silane coupling agent Y-5475. The nickel-plated graphite and carbonyl iron powder are both flake-shaped with a particle size of 50 μm.

[0076] The method for preparing the electrical appliance casing is similar to that in Implementation Case 1.

[0077] Example 3

[0078] Unlike Example 2, the amount of nickel-plated graphite added in this example is 7 parts, while the remaining components and preparation methods are the same as in Example 2.

[0079] The method for preparing the electrical appliance casing is similar to that in Implementation Case 1.

[0080] Example 4

[0081] Unlike Example 2, the amount of nickel-plated graphite added in this example is 10 parts, while the remaining components and preparation methods are the same as in Example 2.

[0082] The method for preparing the electrical appliance casing is similar to that in Implementation Case 1.

[0083] Example 5

[0084] Unlike Example 2, the amount of carbonyl iron powder added in this example is 8 parts, while the remaining components and preparation methods are the same as in Example 2.

[0085] The method for preparing the electrical appliance casing is similar to that in Implementation Case 1.

[0086] Example 6

[0087] Unlike Example 2, the amount of carbonyl iron powder added in this example is 10 parts, while the remaining components and preparation methods are the same as in Example 2.

[0088] The method for preparing the electrical appliance casing is similar to that in Implementation Case 1.

[0089] Example 7

[0090] Unlike Example 1, the electrical casing in this example comprises the following components in parts by weight:

[0091] The composition includes 70 parts polyphenylene sulfide, 15 parts carbon fiber, 5 parts nickel-plated graphite, 5 parts carbonyl iron powder, and 2 parts heat-resistant silane coupling agent Y-5475. The nickel-plated graphite is in flake form with a particle size of 30 μm, and the carbonyl iron powder is in granular form with a particle size of 500 nm.

[0092] The method for preparing the electrical appliance casing is similar to that in Example 1.

[0093] Example 8

[0094] Unlike Example 1, the electrical casing in this example comprises the following components in parts by weight:

[0095] The composition includes 70 parts polyphenylene sulfide, 15 parts glass fiber, 5 parts nickel-plated graphite, 5 parts carbonyl iron powder, and 2 parts heat-resistant silane coupling agent Y-5475. The nickel-plated graphite and carbonyl iron powder are both flake-shaped with a particle size of 30 μm.

[0096] The method for preparing the electrical appliance casing is similar to that in Example 1.

[0097] Comparative Example 1

[0098] Unlike Example 1, the electrical casing in this comparative example comprises the following components in parts by weight:

[0099] 70 parts polyphenylene sulfide and 30 parts glass fiber.

[0100] The preparation method of the electrical appliance casing in this comparative example is similar to that in Example 1.

[0101] Comparative Example 2

[0102] Unlike Example 1, the electrical casing in this comparative example comprises the following components in parts by weight:

[0103] The composition includes 70 parts polyphenylene sulfide, 25 parts glass fiber, 5 parts nickel-plated graphite, and 2 parts heat-resistant silane coupling agent Y-5475. The nickel-plated graphite is in flake form with a particle size of 30 μm.

[0104] The preparation method of the electrical appliance casing in this comparative example is similar to that in Example 1.

[0105] Performance testing

[0106] Performance tests were conducted on Examples 1-8 and Comparative Examples 1-2 in accordance with the following standards: Plastic Density Test Standard GB / T 533, Tensile Strength Test Standard GB / T1040.1-2006, Flexural Modulus Test Standard GB / T 1042-79, and Electromagnetic Shielding Effectiveness Test Standard GJB 8820-2015.

[0107] Test Results

[0108] Table 1 Performance test results for Examples 1-8 and Comparative Examples 1-2

[0109] As can be seen from Table 1, the electromagnetic shielding plastic disclosed in the embodiments of the present invention, which uses conductive filler and magnetic filler to reinforce in a coordinated manner, has low density, excellent mechanical properties and electromagnetic shielding effectiveness. When used as an electrical housing for new energy vehicles to replace metal housings, it can achieve the effects of lightweighting and shielding electromagnetic interference.

[0110] Comparative examples 2-4 show that, with other conditions remaining constant, increasing the amount of nickel-plated graphite improves the electromagnetic shielding effect of the plastic shell. Comparative examples 2 and 5-6 show that, with other conditions remaining constant, increasing the amount of carbonyl iron powder also improves the electromagnetic shielding effect of the plastic shell. Comparative examples 2 and 7 show that, with other conditions remaining constant, sheet-like fillers are more effective at improving the electromagnetic shielding effect of the plastic shell. Comparative examples 2 and 8 show that, with other conditions remaining constant, carbon fiber is more effective than glass fiber in improving the electromagnetic shielding effect of the plastic shell. Therefore, within a certain range, increasing the amount of conductive and magnetic fillers in the material composition, increasing the dimensionality of functional fillers, and changing the reinforcing fiber from glass fiber to carbon fiber can all improve the electromagnetic shielding effect of the plastic shell.

[0111] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A plastic, characterized in that, Includes the following components in parts by weight: 60-80 parts plastic matrix, 10-20 parts reinforcing fiber, 5-10 parts conductive filler, 5-10 parts magnetic filler, and 0.5-2 parts coupling agent.

2. The plastic as described in claim 1, characterized in that, The plastic matrix is ​​selected from at least one of polyphenylene sulfide and polyphthalamide.

3. The plastic as described in claim 1, characterized in that, The reinforcing fiber is selected from at least one of carbon fiber and glass fiber.

4. The plastic as described in claim 1, characterized in that, The conductive and magnetic fillers are in the form of flakes or granules.

5. The plastic as described in claim 4, characterized in that, The particle size of the sheet-like conductive filler and magnetic filler is 30μm-80μm; and / or, The particle size of the granular conductive filler and magnetic filler is 500nm-10μm.

6. The plastic as described in claim 4 or 5, characterized in that, The conductive filler is a carbon-based conductive filler.

7. The plastic as described in claim 6, characterized in that, The conductive filler is selected from at least one of graphene, carbon nanotubes, expanded graphite, graphite sheets, nickel-plated graphite, and carbon black.

8. The plastic as described in claim 4 or 5, characterized in that, The magnetic filler is selected from at least one of iron-based magnetic fillers and nickel-based magnetic fillers.

9. The plastic as described in claim 8, characterized in that, The magnetic filler is selected from at least one of iron-nickel alloy, iron-cobalt alloy, ferrite, and carbonyl iron.

10. The plastic as claimed in claim 11, characterized in that, The coupling agent is selected from at least one of silane coupling agents and titanate coupling agents.

11. A housing, characterized in that, The material of the housing includes the plastic as described in any one of claims 1 to 10.

12. A method for preparing a shell, characterized in that, Mix 60-80 parts by weight of plastic matrix, 10-20 parts by weight of reinforcing fiber, 5-10 parts by weight of conductive filler, 5-10 parts by weight of magnetic filler and 0.5-2 parts by weight of coupling agent evenly, then extrude granulate and injection mold.

13. The method for preparing the shell as described in claim 12, characterized in that, The parameters of the extrusion granulation satisfy at least one of the following conditions: The barrel temperature is 300℃-340℃; The screw speed is 400 r / min-500 r / min; and / or, The injection molding parameters satisfy at least one of the following conditions: The barrel temperature is 300℃-350℃; The nozzle temperature is 320℃-330℃; The mold temperature is 120℃-150℃; The injection pressure is 80MPa-130MPa.

14. The use of a housing as described in claim 11 or a housing prepared by the method described in claim 12 or 13 in an electrical appliance.

Images