Electronic device drop-resistant housing

Abstract

The application relates to the field of electronic equipment, and discloses an anti-falling shell of an electronic equipment, which comprises the following components in parts by weight: 70-85 parts of a high-molecular polymer base material; 10-15 parts of reinforcing fillers; 5-10 parts of impact modifiers; 0.1-0.5 parts of heat stabilizers; 0.1-0.5 parts of antioxidants; and 0.5-1 parts of lubricants; the shell of the electronic equipment is compounded by TPU, aramid fibers and PC, the overall toughness and wear resistance of the material system are significantly improved, the addition of the TPU enables the PC material to better absorb impact energy and reduce damage when the PC material is subjected to the impact and falling that may occur in daily use, the high-strength characteristics of the aramid fibers provide additional impact resistance for the shell of the electronic equipment, the safety of internal components is ensured, and the lightness of the electronic equipment is maintained.

Description

Technical Field

[0001] This invention relates to the field of electronic devices and discloses a shock-resistant casing for electronic devices. Background Technology

[0002] Electronic devices have gradually become an integral part of people's daily lives. However, electronic devices, especially mobile electronic devices such as charging plugs, power banks, portable projectors, wireless headphones, smartwatches, game consoles, and portable media players, are inevitably subject to physical damage such as drops and collisions during use.

[0003] Existing electronic device casings are mostly made of plastic, metal, or alloy materials. While these materials offer some protection for the internal battery and circuit boards, they are significantly inadequate in terms of drop resistance. Metal or alloy casings, although structurally robust, are heavy and can exert considerable impact on internal components upon drop. Plastic casings, while lightweight, have poor impact resistance and are prone to breakage upon impact; furthermore, these materials may deform or become brittle under extreme temperatures, further reducing the safety and durability of electronic devices.

[0004] Because electronic devices contain lithium batteries and other sensitive electronic components, damage to the casing during drops or impacts can lead to battery leaks, short circuits, and even fires or explosions, potentially resulting in the loss of users' personal information. Therefore, improving the drop resistance of electronic device casings is crucial for protecting user safety and data security. A high-performance drop-resistant casing can effectively absorb and disperse the impact of drops, reducing damage to internal components, extending the device's lifespan, and simultaneously increasing user trust and satisfaction.

[0005] In conclusion, developing a lightweight yet highly shock-resistant electronic device casing is of great significance for improving the overall safety and user experience of electronic devices. Summary of the Invention

[0006] In view of the problems of poor impact resistance and easy cracking of traditional plastic electronic device casings in the prior art, one of the objectives of this invention is to provide a shock-resistant casing for electronic devices.

[0007] This invention is achieved through the following technical solution: a shock-resistant casing for electronic devices, comprising the following components by weight:

[0008] 70-85 parts of polymer substrate;

[0009] 10-15 parts of reinforcing filler;

[0010] 5-10 parts impact modifier;

[0011] Heat stabilizer 0.1-0.5 parts;

[0012] Antioxidant 0.1-0.5 parts;

[0013] Lubricant 0.5-1 part.

[0014] As a preferred embodiment of the above technical solution, the polymer substrate is PC; and the impact modifier is TPU.

[0015] TPU, or thermoplastic polyurethane, is a rubber elastomer that forms a tiny dispersed phase within a PC substrate system. The numerous TPU dispersed phases act as stress concentration points in this system, absorbing and dispersing impact energy. When the molded electronic device casing is subjected to external impact, TPU particles can induce microcracks and shear bands in the surrounding resin. The formation and branching of these cracks and shear bands absorb energy, preventing further crack propagation and thus reducing the risk of the electronic device casing cracking, thereby improving its impact resistance.

[0016] As a preferred embodiment of the above technical solution, the antioxidant is a hindered phenolic antioxidant, specifically one or more of antioxidant 1010, antioxidant 1076, and antioxidant 2246; the heat stabilizer is an organophosphate heat stabilizer, specifically one or more of triphenyl phosphite, triisooctyl phosphite, and trinonylphenyl phosphite; and the lubricant is a stearate lubricant.

[0017] As a preferred embodiment of the above technical solution, the reinforcing filler is aramid fiber.

[0018] Aramid fibers (such as Twaron and Kevlar) can enhance the mechanical properties of polymer substrates, particularly in terms of toughness, and they also offer relatively low cost and good compatibility, making them suitable for high-performance applications with limited budgets.

[0019] As a preferred embodiment of the above technical solution, the aspect ratio of the aramid fiber is between 10:1 and 20:1. A long aspect ratio can improve the strength and modulus of the material, but an excessively long aspect ratio can lead to uneven dispersion of the aramid fiber in the system and difficulty in processing. Preferably, the aspect ratio is between 10:1 and 20:1, where the reinforcing effect of the aramid fiber is good.

[0020] As a preferred embodiment of the above technical solution, the average particle size of the aramid fibers is between 10 and 20 micrometers. Using aramid fibers with a particle size range allows for sufficient dispersion in the system, providing a uniform reinforcing effect, while avoiding stress concentration and material defects caused by large-particle-size aramid fibers.

[0021] As a preferred embodiment of the above technical solution, the aramid fiber needs to undergo modification treatment. The modification treatment steps include stirring the aramid fiber in a polydopamine buffer solution of 1.5-3.5 mg / ml for 22-26 hours; then drying the polydopamine-coated aramid fiber at room temperature for 24 hours, and then immersing it in a solution of 1.5-2.5 wt% γ-aminopropyltriethoxysilane (silane coupling agent KH550) for 22-26 hours to obtain the modified aramid fiber.

[0022] By pretreating aramid fibers and coating them with a polydopamine (PDA) coating, relevant functional hydroxyl groups are introduced, providing abundant reactive sites and enhancing the compatibility and adhesion between the fibers and PC. Simultaneously, the drying process increases the adhesion stability of the PDA coating, making it less prone to peeling off in subsequent steps. KH550 molecules fully contact and covalently bond with the hydroxyl groups on the PDA surface, enhancing the interfacial bonding between the aramid fibers and PC resin, thereby significantly improving the overall performance of the PC material.

[0023] As a preferred embodiment of the above technical solution, the buffer solution used in the polydopamine buffer solution is a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer solution, and the pH value of the buffer solution is 8.5.

[0024] The second objective of this invention is to provide a method for preparing a shock-resistant casing for electronic devices, comprising the following steps:

[0025] Step S1: Dry the polymer substrate and reinforcing filler to maintain the moisture content of the dried polymer substrate and reinforcing filler at less than 0.04%.

[0026] Step S2: After drying in Step S1, the polymer matrix, reinforcing filler, impact modifier, heat stabilizer, antioxidant, and lubricant are mixed in proportion and then melt-mixed through a twin-screw extruder to ensure uniform dispersion of each component;

[0027] Step S3: Using injection molding, molten plastic is injected into a mold to form the shape of the electronic device casing;

[0028] Step S4: Perform post-processing on the outer shell as needed, such as grinding, spraying, or laser engraving.

[0029] In step S1, the drying conditions are: maintaining the temperature within the range of 90℃-110℃ and continuing to dry for 2-4 hours.

[0030] Beneficial effects:

[0031] The formula and preparation process used in this invention can be used to mold the housings of various plastic electronic devices, including charging plugs, power banks, portable projectors, wireless headphones, smartwatches, game consoles, portable media players, portable printers, solar chargers, and so on.

[0032] The electronic device housing of this invention utilizes a composite of thermoplastic polyurethane (TPU), aramid fiber, and PC, significantly enhancing the overall toughness and abrasion resistance of the material system. The addition of TPU allows the PC material to better absorb impact energy and reduce damage when subjected to impacts and drops that may occur during daily use. Simultaneously, the high strength of the aramid fiber provides additional impact resistance to the electronic device housing. In particular, modified aramid fiber systematically improves the mechanical properties of the electronic device housing, including tensile strength, flexural strength, and notched impact strength, ensuring the safety of internal components while maintaining the lightweight nature of the electronic device. Detailed Implementation

[0033] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] A shock-resistant casing for electronic devices, comprising the following components by weight:

[0035] PC70-85 copies;

[0036] 10-15 parts of aramid fiber;

[0037] 5-10 portions of TPU;

[0038] 0.1–0.5 parts of organophosphate heat stabilizer;

[0039] 0.1–0.5 parts of hindered phenolic antioxidants;

[0040] Stearate lubricant 0.5-1 part.

[0041] Specifically, the hindered phenolic antioxidant can be one or more of antioxidant 1010, antioxidant 1076, and antioxidant 2246.

[0042] The organophosphate heat stabilizer can be one or more of the following: triphenyl phosphite, triisooctyl phosphite, and trinonylphenyl phosphite.

[0043] The lubricant is a stearate lubricant.

[0044] Aramid fibers have an aspect ratio between 10:1 and 20:1, and an average particle size between 10 and 20 micrometers.

[0045] Aramid fibers require modification treatment. The modification process includes continuously stirring the aramid fibers in a polydopamine buffer solution of 1.5–3.5 mg / ml for 22–26 hours. The polydopamine buffer solution used is a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer solution with a pH of 8.5. After drying the polydopamine-coated aramid fibers at room temperature for 24 hours, they are then immersed in a solution of 1.5–2.5 wt% γ-aminopropyltriethoxysilane (silane coupling agent KH550) for 22–26 hours to obtain modified aramid fibers.

[0046] A method for preparing a shock-resistant casing for electronic devices includes the following steps:

[0047] Step S1: Dry the PC, aramid fiber / modified aramid fiber, keeping the humidity of the dried PC, aramid fiber / modified aramid fiber less than 0.04%; the drying conditions are: keep the temperature in the range of 90℃-110℃ and continue drying for 2-4 hours.

[0048] Step S2: After drying in Step S1, PC, aramid fiber / modified aramid fiber, TPU, heat stabilizer, antioxidant, and lubricant are mixed in proportion and then melt-mixed through a twin-screw extruder to ensure uniform dispersion of each component.

[0049] Step S3: Using injection molding, molten plastic is injected into a mold to form the shape of the electronic device casing;

[0050] Step S4: Perform post-processing on the outer shell as needed, such as grinding, spraying, or laser engraving.

[0051] The following describes an example.

[0052] All raw materials used in the embodiments of this invention can be purchased directly from the market.

[0053] The polymer substrate PC used in this embodiment has a density of 1.18-1.22 g / cm³. 3 Between these values, the heat distortion temperature is 135℃, and the linear expansion coefficient is 3.8×10^-5cm / ℃. The TPU is made from polyester or polyether diol soft segments with an average molecular weight of 2000.

[0054] A power bank casing mold was used to form the power bank casing, and the formulation and process method of this invention were verified through embodiments. Specific embodiments are as follows.

[0055] Example 1

[0056] The raw materials and formulations in this embodiment are as follows:

[0057] 70 parts PC, 13 parts aramid fiber, 8 parts TPU, 0.5 parts organophosphate heat stabilizer, 0.3 parts hindered phenolic antioxidant, and 0.5 parts stearate lubricant.

[0058] Among them, the hindered phenolic antioxidant is antioxidant 1010.

[0059] The organophosphate heat stabilizer selected is triisooctyl phosphite.

[0060] Any type of stearate lubricant can be used.

[0061] The aspect ratio of aramid fiber is 10:1, and the average particle size is 10 micrometers.

[0062] In this embodiment, the aramid fiber was not modified.

[0063] The preparation method is as follows:

[0064] Step S1: Dry the PC and aramid fibers under the following conditions: maintain a temperature between 90℃ and 110℃ for 4 hours. Ensure the moisture content of the dried PC and aramid fibers / modified aramid fibers is less than 0.04%.

[0065] Step S2: After drying in step S1, PC, aramid fiber, TPU, heat stabilizer, antioxidant, lubricant, etc. are mixed in proportion and then melt-mixed through a twin-screw extruder to ensure that each component is evenly dispersed.

[0066] Step S3: Using injection molding, molten plastic is injected into a mold to form the shape of the electronic device casing;

[0067] Step S4: Perform post-processing such as grinding, spraying or laser engraving on the outer casing as needed to form the outer casing of the electronic device.

[0068] Example 2

[0069] The raw materials and formulations in this embodiment are as follows:

[0070] 80 parts PC, 10 parts aramid fiber, 10 parts TPU, 0.1 parts organophosphate heat stabilizer, 0.5 parts hindered phenolic antioxidant, 1 part stearate lubricant.

[0071] Among them, the hindered phenolic antioxidant selected is antioxidant 1076.

[0072] Triphenyl phosphite was selected as the organophosphate heat stabilizer.

[0073] Any type of stearate lubricant can be used.

[0074] The aspect ratio of aramid fiber is 10:1, and the average particle size is 10 micrometers.

[0075] In this embodiment, the aramid fiber was not modified.

[0076] The preparation method is as follows:

[0077] Step S1: Dry the PC and aramid fibers under the following conditions: maintain a temperature between 90℃ and 110℃ for 3 hours. Ensure the moisture content of the dried PC and aramid fibers / modified aramid fibers is less than 0.04%.

[0078] Step S2: After drying in step S1, PC, aramid fiber, TPU, heat stabilizer, antioxidant, lubricant, etc. are mixed in proportion and then melt-mixed through a twin-screw extruder to ensure that each component is evenly dispersed.

[0079] Step S3: Using injection molding, molten plastic is injected into a mold to form the shape of the electronic device casing;

[0080] Step S4: Perform post-processing such as grinding, spraying or laser engraving on the outer casing as needed to form the outer casing of the electronic device.

[0081] Example 3

[0082] The raw materials and formulations in this embodiment are as follows:

[0083] 80 parts PC, 10 parts aramid fiber, 10 parts TPU, 0.1 parts organophosphate heat stabilizer, 0.5 parts hindered phenolic antioxidant, 1 part stearate lubricant.

[0084] Among them, the hindered phenolic antioxidants are antioxidant 1076 and antioxidant 2246 mixed in a 1:1 ratio.

[0085] Trinonylphenyl phosphite was selected as the organophosphate heat stabilizer.

[0086] Any type of stearate lubricant can be used.

[0087] The aspect ratio of aramid fiber is 10:1, and the average particle size is 10 micrometers.

[0088] In this embodiment, the aramid fiber was not modified.

[0089] The preparation method is as follows:

[0090] Step S1: Dry the PC and aramid fibers under the following conditions: maintain a temperature between 90℃ and 110℃ for 3 hours. Ensure the moisture content of the dried PC and aramid fibers / modified aramid fibers is less than 0.04%.

[0091] Step S2: After drying in step S1, PC, aramid fiber, TPU, heat stabilizer, antioxidant, lubricant, etc. are mixed in proportion and then melt-mixed through a twin-screw extruder to ensure that each component is evenly dispersed.

[0092] Step S3: Using injection molding, molten plastic is injected into a mold to form the shape of the electronic device casing;

[0093] Step S4: Perform post-processing such as grinding, spraying or laser engraving on the outer casing as needed to form the outer casing of the electronic device.

[0094] Example 4

[0095] The difference between this embodiment and Embodiment 1 is that the aspect ratio of the aramid fibers used is different. The aspect ratio of the aramid fibers used in this embodiment is 15:1.

[0096] Example 5

[0097] The difference between this embodiment and Embodiment 1 is that the aspect ratio of the aramid fibers used is different. The aspect ratio of the aramid fibers used in this embodiment is 20:1.

[0098] Example 6

[0099] The difference between this embodiment and Embodiment 4 is that the particle size of the aramid fiber used is different. The aramid fiber used in this embodiment has a particle size of 15 micrometers.

[0100] Example 7

[0101] The difference between this embodiment and Embodiment 4 is that the particle size of the aramid fiber used is different. The aramid fiber used in this embodiment has a particle size of 20 micrometers.

[0102] Example 8

[0103] The difference between this embodiment and Embodiment 4 is that the aramid fiber used has undergone modification treatment. The aramid fiber used in this embodiment has undergone the following modification steps:

[0104] Aramid fibers were continuously stirred in a 1.5 mg / ml polydopamine buffer solution for 22 hours. The polydopamine buffer solution used was a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer with a pH of 8.5. The polydopamine-coated aramid fibers were then dried at room temperature for 24 hours and subsequently immersed in a 1.5 wt% solution of γ-aminopropyltriethoxysilane (silane coupling agent KH550) for 22 hours to obtain modified aramid fibers.

[0105] Example 9

[0106] The difference between this embodiment and Embodiment 8 lies in the details of the aramid fiber modification treatment. In this embodiment, the aramid fiber undergoes the following modification steps:

[0107] Aramid fibers were continuously stirred in a 2.0 mg / ml polydopamine buffer solution for 24 hours. The polydopamine buffer solution used was a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer with a pH of 8.5. The polydopamine-coated aramid fibers were then dried at room temperature for 24 hours and subsequently immersed in a 2.0 wt% solution of γ-aminopropyltriethoxysilane (silane coupling agent KH550) for 24 hours to obtain modified aramid fibers.

[0108] Example 10

[0109] The difference between this embodiment and Embodiment 8 lies in the details of the aramid fiber modification treatment. In this embodiment, the aramid fiber undergoes the following modification steps:

[0110] Aramid fibers were continuously stirred in a 3.5 mg / ml polydopamine buffer solution for 26 hours. The polydopamine buffer solution used was a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer with a pH of 8.5. The polydopamine-coated aramid fibers were then dried at room temperature for 24 hours and subsequently immersed in a 2.5 wt% solution of γ-aminopropyltriethoxysilane (silane coupling agent KH550) for 26 hours to obtain modified aramid fibers.

[0111] Comparative Example 1

[0112] Commercially available power banks. The size and weight of the power bank were chosen to be similar to the power bank casing prepared in the example.

[0113] Comparative Example 2

[0114] The difference between this comparative example and Example 1 is that the proportions of the formulations in this comparative example and Example 1 are different.

[0115] The raw materials and proportions for this comparative example are as follows:

[0116] 88 parts PC, 18 parts aramid fiber, 3 parts TPU, 0.6 parts organophosphate heat stabilizer, 0.1 parts hindered phenolic antioxidant, and 1 part stearate lubricant.

[0117] Comparative Example 3

[0118] The difference between this comparative example and Example 1 is that the proportions of the formulations in this comparative example and Example 1 are different.

[0119] The raw materials and proportions for this comparative example are as follows:

[0120] 65 parts PC, 8 parts aramid fiber, 15 parts TPU, 0.1 parts organophosphate heat stabilizer, 0.5 parts hindered phenolic antioxidant, 1 part stearate lubricant.

[0121] Comparative Example 4

[0122] The difference between this comparative example and Example 4 is that the aspect ratio of the aramid fibers used is different. The aspect ratio of the aramid fibers used in this comparative example is 25:1.

[0123] Comparative Example 5

[0124] The difference between this comparative example and Example 4 is that the particle size of the aramid fibers used is different. The aramid fibers used in this comparative example have a particle size of 25 micrometers.

[0125] Comparative Example 6

[0126] The difference between this comparative example and Example 4 is that the particle size of the aramid fibers used is different. The aramid fibers used in this comparative example have a particle size of 8 micrometers.

[0127] Comparative Example 7

[0128] The difference between this comparative example and Example 9 lies in the modification steps of the aramid fiber. The aramid fiber used in this comparative example underwent the following modification steps:

[0129] Aramid fibers were reacted in a 2.0 mg / ml polydopamine buffer solution with continuous stirring for 24 hours. The polydopamine buffer solution used was a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer solution with a pH of 8.5. The polydopamine-coated aramid fibers were then dried at room temperature for 24 hours to obtain modified aramid fibers.

[0130] Comparative Example 8

[0131] The difference between this embodiment and Embodiment 9 lies in the details of the aramid fiber modification treatment. The aramid fiber used in this comparative example underwent the following modification steps:

[0132] Aramid fibers were continuously stirred in a 1.0 mg / ml polydopamine buffer solution for 24 hours. The polydopamine buffer solution used was a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer with a pH of 8.5. The polydopamine-coated aramid fibers were then dried at room temperature for 24 hours and subsequently immersed in a 2.0 wt% solution of γ-aminopropyltriethoxysilane (silane coupling agent KH550) for 24 hours to obtain modified aramid fibers.

[0133] Comparative Example 9

[0134] The difference between this comparative example and Example 1 is that an equal amount of PC is used to replace TPU in this comparative example.

[0135] Testing and Inspection

[0136] The electronic device casings prepared in Examples 1-10 all meet the requirements of having a thermal conductivity greater than 1.7 W / m*K and a flame retardancy rating of V-0. The power bank casings prepared in Examples 1-10 are approximately 10%-20% lighter than the power bank casing of the same size in Comparative Example 1.

[0137] The charger housings prepared in Examples 1-10 and Comparative Examples 1-9 were subjected to performance tests to further verify the superior performance of the electronic device housings prepared using the formulation and manufacturing process of the present invention. Specifically, the performance tests included tensile strength, flexural strength, flexural modulus, roller drop test, impact strength, impact strength retention rate for weather resistance, and impact strength retention rate for damp heat resistance. The methods for each test are described below:

[0138] Tensile strength (a measure of the maximum force that an electronic device housing can withstand when subjected to tensile force, reflecting the strength and durability of the electronic device housing): ISO 527, tensile speed 5 mm / min.

[0139] Bending strength (a measure of the stiffness that the housing of an electronic device can withstand when bent, reflecting the deformation resistance of the housing of the electronic device): ISO 178:2019, bending speed 2 mm / min.

[0140] Roller drop test: The wireless charger housing is injection molded and assembled into a product (the product already has the electronic components for wireless charging installed). After being stored at 23°C for 12 hours, it is dropped freely from a height of 50cm onto the surface of the product for 300 consecutive times. If no cracks are observed, it is considered to have passed the test.

[0141] Impact strength test (tests the performance of electronic device housings under sudden impacts, ensuring their impact resistance during daily use and the attenuation of the housing material's impact resistance after prolonged exposure to harsh environments (such as high temperature, high humidity, and temperature changes).

[0142] 1. Notched impact strength, ISO 180, at 23°C.

[0143] 2. The impact strength retention rate of damp heat resistance refers to the percentage of the notched impact strength tested at 85% humidity, 85℃, and 1000h compared to the notched impact strength tested at 23℃.

[0144] 3. The impact strength retention rate of weather resistance refers to the percentage of the notched impact strength tested after ASTM G155-13 cycle 1 and UV aging to the notched impact strength tested at 23°C.

[0145] The test results are as follows:

[0146] Table 1 Performance test results of electronic device housings prepared in Examples 1-10 and Comparative Examples 1-8

[0147]

[0148]

[0149] Based on the above test results, the electronic device casing prepared according to the embodiments of the present invention exhibits excellent drop resistance. From high tensile and flexural strength to notched impact performance and the ability to pass the roller drop test, these factors collectively demonstrate that the electronic device casing prepared using the raw materials of the present invention and the proportions within the limits of the present invention possesses a robust drop resistance system, enabling electronic devices to effectively withstand various accidental drops and impacts during daily use.

[0150] Specifically, further analysis combining Examples 8-10 and Example 4 with the test data in Table 1 reveals that aramid fibers have a smooth surface and few active groups. During blending with polymer resins, they cannot fully exert their tensile strength and crack-blocking toughening effects. After modification, the polydopamine (PDA) coating on the aramid fibers provides abundant hydroxyl groups. These hydroxyl groups can act as reactive sites, forming covalent bonds with KH550 molecules. One end of KH550 can react with the hydroxyl groups of the PDA coating, while the other end forms a stable chemical bond with the PC resin. These covalent bonds enhance the interfacial bonding between the aramid fibers and the PC resin, thereby improving the overall mechanical properties and stability of the material, resulting in excellent impact resistance.

[0151] Based on the comparative examples 7-8, examples 8-10, and the test data in Table 1, it can be concluded that when using the modification method of the present invention, the aramid fibers exhibit good macroscopic mechanical properties in the system. The modification effect is particularly good when using a solution of 2.0 mg / ml polydopamine buffer and 2.0 wt% γ-aminopropyltriethoxysilane (silane coupling agent KH550). Not only do the tensile and flexural strengths show excellent performance (tensile strength 125 MPa, flexural strength 200 MPa), but even after prolonged exposure of electronic devices to high temperature, high humidity, and large temperature variations, as well as in reverse impact strength testing, the fibers still maintain a high retention rate of approximately 95%.

[0152] Based on Comparative Examples 4-6 and the Examples, as well as the test data in Table 1, the selection of the aspect ratio and particle size of aramid fibers in the whole system has a significant impact on the mechanical strength of the formed electronic device housing.

[0153] It should be understood that the above embodiments are exemplary and are not intended to encompass all possible implementations included in the claims. Various modifications and changes can be made to the above embodiments without departing from the scope of this disclosure. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form other embodiments of the present invention that may not be explicitly described. Therefore, the above embodiments only illustrate several implementations of the present invention and do not limit the scope of protection of this patent.

Claims

1. A shock-resistant casing for electronic devices, characterized in that, The following components are included in parts by weight: 70-85 parts of polymer substrate; 10-15 parts of reinforcing filler; 5-10 parts impact modifier; Heat stabilizer 0.1-0.5 parts; Antioxidant 0.1-0.5 parts; Lubricant 0.5-1 part; Wherein, the polymer substrate is PC; the impact modifier is TPU; and the reinforcing filler is aramid fiber; The aspect ratio of the aramid fiber is between 10:1 and 20:1, and the average particle size of the aramid fiber is between 10 and 20 micrometers. The aramid fiber needs to undergo modification treatment. The modification treatment steps include stirring the aramid fiber in a polydopamine buffer solution of 1.5-3.5 mg / ml for 22-26 hours; then drying the polydopamine-coated aramid fiber at room temperature for 24 hours, and then immersing it in a solution of 1.5-2.5 wt% γ-aminopropyltriethoxysilane for 22-26 hours to obtain the modified aramid fiber.

2. The impact-resistant casing for an electronic device according to claim 1, characterized in that, The antioxidant is a hindered phenolic antioxidant; the heat stabilizer is an organophosphate heat stabilizer; and the lubricant is a stearate lubricant.

3. The impact-resistant casing for electronic devices according to claim 1, characterized in that, The polydopamine buffer solution used is a 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride buffer solution with a pH of 8.

5.

4. A method for preparing a drop-resistant casing for electronic devices according to any one of claims 1-3, characterized in that, Includes the following steps: Step S1: Dry the polymer substrate and reinforcing filler to maintain a moisture content of less than 0.04% after drying. Step S2: After drying in Step S1, the polymer matrix, reinforcing filler, impact modifier, heat stabilizer, antioxidant, and lubricant are mixed in proportion and then melt-mixed through a twin-screw extruder to ensure uniform dispersion of each component; Step S3: Using injection molding, molten plastic is injected into a mold to form the shape of the electronic device casing; Step S4: Perform post-processing on the outer shell as needed, such as grinding, spraying, or laser engraving.

5. The method for preparing a shock-resistant casing for electronic devices according to claim 4, characterized in that, In step S1, the drying conditions are: maintaining the temperature within the range of 90°C-110°C and continuing to dry for 2-4 hours.

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