Electromagnetic shielding PMMA composite board material and preparation method thereof

Abstract

The application relates to the technical field of polymer materials, in particular to an electromagnetic shielding PMMA (polymethyl methacrylate) composite board material and a preparation method thereof. The electromagnetic shielding PMMA composite board material is prepared from the following raw materials in parts by weight: 90-110 parts of methyl methacrylate, 3-5 parts of pentaerythritol phosphate, 0.6-1.2 parts of dimethyl silicone oil, 4-7 parts of nano titanium dioxide, 2-3 parts of zirconium phosphate, 0.5-0.8 parts of an initiator, 5-8 parts of an electromagnetic shielding agent, 2-3 parts of a flame-retardant aid, 3-6 parts of an antistatic agent, 2-5 parts of a lubricant and 3-6 parts of a pigment. The PMMA composite board material prepared by the application not only has excellent electromagnetic shielding performance, but also has excellent flame-retardant performance, effectively ensuring the grade and quality of the PMMA composite board material.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to an electromagnetic shielding PMMA composite plate material and its preparation method. Background Technology

[0002] Acrylic sheets, commonly referred to as acrylic sheets, are made of polymethyl methacrylate (PMMA), which is polymerized from methyl methacrylate monomers (MMA). Alternatively, they can be produced by extruding acrylic granules using an extruder. Previously, these sheets were commonly known as plexiglass. The term "acrylic" originates from the English word "acrylic," referring to PMMA sheets made from the organic compound MMA, whose transparency and light transmittance are similar to glass. The term "plexiglass" is used to refer to all sheets made from transparent plastics such as PS and PC, or from low-quality recycled MMA. Due to its good transparency, chemical stability, weather resistance, ease of dyeing, ease of processing, and beautiful appearance, acrylic has a wide range of applications in the construction industry.

[0003] Patent application CN201610409978.2 discloses an antibacterial and flame-retardant acrylic sheet and its preparation method. The antibacterial and flame-retardant acrylic sheet is prepared from the following raw materials in parts by weight: 95-105 parts methyl methacrylate, 0.1-0.7 parts benzoyl peroxide, 15-25 parts magnesium hydroxide, 0.1-0.5 parts dimethyl silicone oil, 1-5 parts inorganic antibacterial agent, and 0.5-1.5 parts antistatic agent. While the acrylic sheet prepared in this patent possesses certain flame-retardant properties and excellent antibacterial properties, its electromagnetic shielding performance is relatively poor. Electromagnetic radiation pollution has become a new form of environmental pollution, causing serious interference to everyday communication equipment, computers, and other electronic systems, posing a serious threat to information security, and also causing incalculable harm to human health. Furthermore, its flame-retardant properties are relatively insufficient, potentially leading to fires and posing certain safety hazards, requiring further improvement. Based on this, the present invention provides an electromagnetic shielding PMMA composite plate material and its preparation method, which solves the above-mentioned technical problems! Summary of the Invention

[0004] The purpose of this invention is to provide an electromagnetic shielding PMMA composite board material and its preparation method. The prepared PMMA composite board material not only has excellent electromagnetic shielding performance, but also excellent flame retardant performance, effectively ensuring its grade and quality.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An electromagnetic shielding PMMA composite board material is composed of the following raw materials in parts by weight: 90-110 parts methyl methacrylate, 3-5 parts pentaerythritol phosphate, 0.6-1.2 parts dimethyl silicone oil, 4-7 parts nano titanium dioxide, 2-3 parts zirconium phosphate, 0.5-0.8 parts initiator, 5-8 parts electromagnetic shielding agent, 2-3 parts flame retardant, 3-6 parts antistatic agent, 2-5 parts lubricant, and 3-6 parts pigment.

[0007] Furthermore, the initiator is selected from any one of benzoyl peroxide, diisobutyryl peroxide, and cumyl peroxide neodecanoate.

[0008] Furthermore, the preparation method of the electromagnetic shielding agent is as follows: Add cobalt chloride at a mass of 0.6 to 0.7 times that of ferric chloride to a 0.02–0.05 g / mL ferric chloride aqueous solution, mix and stir evenly, then add an aqueous dispersion of graphene oxide to the resulting mixed solution, ultrasonically disperse for 30–40 min, adjust the pH to 10.5–11.5, then add sodium thiosulfate at a molar amount of 0.3 to 0.4 times that of ferric chloride, mix evenly, seal, and heat at 130–170°C for 20–40 h; after the reaction is complete, allow it to cool naturally to room temperature, and then sequentially centrifuge, wash, and dry the resulting product components to obtain the electromagnetic shielding agent.

[0009] Furthermore, the concentration of graphene oxide in the aqueous dispersion is 10-20 g / L, and its amount is 5-8% of the volume of the mixed solution.

[0010] Furthermore, the preparation method of the flame retardant additive includes the following steps: 1,4-diaminobenzene is added to anhydrous ethanol at a dosage ratio of 0.15-0.25 mol / L, and the mixture is stirred under nitrogen protection until it is completely dissolved. Then, phenylphosphonic acid with a molar amount of 0.8-1.2 times that of 1,4-diaminobenzene is added to the resulting mixture, and the mixture is stirred evenly and then refluxed for 3-5 hours. After the reaction is completed, the resulting product is naturally cooled to room temperature, and the reaction is continued to be stirred at room temperature for 6-10 hours. After the reaction is completed, the resulting reaction product is subjected to solid-liquid separation, and then the resulting solid filter material is washed with anhydrous ethanol until the resulting filtrate is a colorless and transparent liquid. The washed solid material is then vacuum dried to obtain the flame retardant additive.

[0011] Furthermore, the vacuum drying temperature is set to 70–80°C, and the vacuum drying time is set to 10–12 hours.

[0012] Furthermore, the antistatic agent is selected from one of N-hydroxymethylacrylamide, N-(2-hydroxypropyl)methacrylamide, and N-hydroxymethylacrylamide.

[0013] Furthermore, the lubricant is selected from any one of stearic acid, polyethylene wax, ethylene bis-stearamide, and silicone powder.

[0014] Furthermore, the pigment is selected from any one of chrome yellow, iron oxide black, and iron oxide red.

[0015] A method for preparing an electromagnetic shielding PMMA composite plate material includes the following steps:

[0016] Step 1: Accurately weigh each raw material according to the formula, then add methyl methacrylate and initiator together into the reactor, mix and stir evenly, and heat and polymerize in a water bath at 80-85℃ for 30-40 minutes.

[0017] Step 2: After the reaction is complete, allow the resulting product components to cool naturally to room temperature. Then add the remaining raw materials, mix and stir evenly, and pour the resulting slurry into the corresponding mold. After sequentially undergoing air bath heating polymerization, cooling and demolding treatment, the electromagnetic shielding PMMA composite board material is obtained.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] This invention involves adding cobalt chloride to an aqueous solution of ferric chloride, mixing and stirring until homogeneous, then adding an aqueous dispersion of graphene oxide and sodium thiosulfate, mixing and stirring until homogeneous, and heating to induce a redox reaction. The resulting product components are then centrifuged, washed, and dried to obtain an electromagnetic shielding agent. The obtained electromagnetic shielding agent is composed of a highly conductive metal complex salt oxide and graphene, which synergistically and effectively ensure the electromagnetic shielding performance of the PMMA composite board material. Furthermore, this invention involves adding 1,4-diaminobenzene to anhydrous ethanol, then adding phenylphosphonic acid, mixing and stirring until homogeneous, and then refluxing. After the reaction is complete, the mixture is cooled and stirred further. The resulting reaction product is then subjected to solid-liquid separation, washing, and vacuum drying to finally obtain a flame-retardant additive. The prepared flame-retardant additive significantly improves the flame-retardant performance of the PMMA composite board material, effectively enhancing its quality. In summary, the PMMA composite board material prepared by this invention not only possesses excellent electromagnetic shielding performance but also excellent flame-retardant performance, effectively ensuring its grade and quality. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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.

[0021] Example 1

[0022] An electromagnetic shielding PMMA composite board material is composed of the following raw materials in parts by weight: 90 parts methyl methacrylate, 3 parts pentaerythritol phosphate, 0.6 parts dimethyl silicone oil, 4 parts nano titanium dioxide, 2 parts zirconium phosphate, 0.5 parts benzoyl peroxide, 5 parts electromagnetic shielding agent, 2 parts flame retardant additive, 3 parts N-hydroxymethylacrylamide, 2 parts stearic acid and 3 parts chrome yellow.

[0023] The electromagnetic shielding agent is prepared as follows: Cobalt chloride with a mass of 0.6 times that of ferric chloride is added to a 0.02 g / mL ferric chloride aqueous solution. After mixing and stirring evenly, an aqueous dispersion of graphene oxide is added to the resulting mixed solution. After ultrasonic dispersion for 30 min, the pH is adjusted to 10.5. Then, sodium thiosulfate with a molar amount of 0.3 times that of ferric chloride is added. After mixing evenly, the solution is sealed and heated at 130℃ for 20 h. After the reaction is complete, the solution is naturally cooled to room temperature. The resulting product components are then centrifuged, washed, and dried sequentially to obtain the electromagnetic shielding agent. The concentration of graphene oxide in the aqueous dispersion is 10 g / L, and its amount is 5% of the volume of the mixed solution.

[0024] The preparation method of the flame retardant additive includes the following steps: 1,4-diaminobenzene is added to anhydrous ethanol at a dosage ratio of 0.15 mol / L, and the mixture is stirred under nitrogen protection until it is completely dissolved. Then, phenylphosphonic acid with a molar amount of 0.8 times that of 1,4-diaminobenzene is added to the resulting mixture, and the mixture is stirred evenly and refluxed for 3 hours. After the reaction is completed, the resulting product is naturally cooled to room temperature, and the reaction is continued to be stirred at room temperature for 6 hours. After the reaction is completed, the resulting reaction product is subjected to solid-liquid separation, and the resulting solid filter material is washed with anhydrous ethanol until the resulting filtrate is a colorless and transparent liquid. The washed solid material is then vacuum dried to obtain the flame retardant additive. The vacuum drying temperature is set to 70℃, and the vacuum drying time is set to 10 hours.

[0025] A method for preparing an electromagnetic shielding PMMA composite plate material includes the following steps:

[0026] Step 1: Accurately weigh each raw material according to the formula, then add methyl methacrylate and initiator together into the reactor, mix and stir evenly, and heat and polymerize in a water bath at 80°C for 30 minutes.

[0027] Step 2: After the reaction is complete, allow the resulting product components to cool naturally to room temperature. Then add the remaining raw materials, mix and stir thoroughly, and pour the resulting slurry into the corresponding molds. After sequentially undergoing air bath heating polymerization, cooling, and demolding treatment, the electromagnetic shielding PMMA composite board material is obtained.

[0028] Example 2

[0029] The preparation method of the electromagnetic shielding PMMA composite board material provided in this embodiment is basically the same as that in Embodiment 1, except that the specific composition of the raw materials used and the preparation methods of the electromagnetic shielding agent and flame retardant are not exactly the same. The specific composition of the raw materials used and the preparation methods of the electromagnetic shielding agent and flame retardant in this embodiment are as follows:

[0030] An electromagnetic shielding PMMA composite board material is composed of the following raw materials in parts by weight: 100 parts methyl methacrylate, 4 parts pentaerythritol phosphate, 1.0 part dimethyl silicone oil, 5 parts nano titanium dioxide, 2.5 parts zirconium phosphate, 0.6 parts diisobutyryl peroxide, 6 parts electromagnetic shielding agent, 2.5 parts flame retardant additive, 4 parts N-(2-hydroxypropyl)methacrylamide, 3 parts polyethylene wax and 5 parts iron oxide black.

[0031] The electromagnetic shielding agent is prepared as follows: Cobalt chloride with a mass of 0.65 times that of ferric chloride is added to a 0.03 g / mL ferric chloride aqueous solution. After mixing and stirring evenly, an aqueous dispersion of graphene oxide is added to the resulting mixed solution. After ultrasonic dispersion for 35 min, the pH is adjusted to 11. Then, sodium thiosulfate with a molar amount of 0.35 times that of ferric chloride is added. After mixing evenly, the solution is sealed and heated at 150℃ for 30 h. After the reaction is complete, the solution is naturally cooled to room temperature. The resulting product components are then centrifuged, washed, and dried sequentially to obtain the electromagnetic shielding agent. The concentration of graphene oxide in the aqueous dispersion is 15 g / L, and its amount is 6% of the volume of the mixed solution.

[0032] The preparation method of the flame retardant additive includes the following steps: 1,4-diaminobenzene is added to anhydrous ethanol at a dosage ratio of 0.2 mol / L, and the mixture is stirred under nitrogen protection until it is completely dissolved. Then, phenylphosphonic acid with an equimolar amount of 1,4-diaminobenzene is added to the resulting mixture, and the mixture is stirred evenly and refluxed for 4 hours. After the reaction is completed, the resulting product is naturally cooled to room temperature, and the reaction is continued to be stirred at room temperature for 8 hours. After the reaction is completed, the resulting reaction product is subjected to solid-liquid separation, and the resulting solid filter material is washed with anhydrous ethanol until the resulting filtrate is a colorless and transparent liquid. The washed solid material is then vacuum dried to obtain the flame retardant additive. The vacuum drying temperature is set to 75℃, and the vacuum drying time is set to 12 hours.

[0033] Example 3

[0034] The preparation method of the electromagnetic shielding PMMA composite board material provided in this embodiment is basically the same as that in Embodiment 1, except that the specific composition of the raw materials used and the preparation methods of the electromagnetic shielding agent and flame retardant are not exactly the same. The specific composition of the raw materials used and the preparation methods of the electromagnetic shielding agent and flame retardant in this embodiment are as follows:

[0035] An electromagnetic shielding PMMA composite board material is composed of the following raw materials in parts by weight: 110 parts methyl methacrylate, 5 parts pentaerythritol phosphate, 1.2 parts dimethyl silicone oil, 7 parts nano titanium dioxide, 3 parts zirconium phosphate, 0.8 parts cumene peroxyneodecanate, 8 parts electromagnetic shielding agent, 3 parts flame retardant additive, 6 parts N-hydroxymethylacrylamide, 5 parts ethylene bis-stearamide, and 6 parts iron oxide red.

[0036] The electromagnetic shielding agent is prepared as follows: Cobalt chloride with a mass of 0.7 times that of ferric chloride is added to a 0.05 g / mL ferric chloride aqueous solution. After mixing and stirring evenly, an aqueous dispersion of graphene oxide is added to the resulting mixed solution. After ultrasonic dispersion for 40 min, the pH is adjusted to 11.5. Then, sodium thiosulfate with a molar amount of 0.4 times that of ferric chloride is added. After mixing evenly, the solution is sealed and heated at 170℃ for 40 h. After the reaction is complete, the solution is naturally cooled to room temperature. The resulting product components are then centrifuged, washed, and dried sequentially to obtain the electromagnetic shielding agent. The concentration of graphene oxide in the aqueous dispersion is 20 g / L, and its amount is 8% of the volume of the mixed solution.

[0037] The preparation method of the flame retardant additive includes the following steps: 1,4-diaminobenzene is added to anhydrous ethanol at a dosage ratio of 0.25 mol / L, and the mixture is stirred under nitrogen protection until it is completely dissolved. Then, phenylphosphonic acid with a molar amount of 1.2 times that of 1,4-diaminobenzene is added to the resulting mixture, and the mixture is stirred evenly and refluxed for 5 hours. After the reaction is completed, the resulting product is naturally cooled to room temperature, and the reaction is continued to be stirred at room temperature for 10 hours. After the reaction is completed, the resulting reaction product is subjected to solid-liquid separation, and the resulting solid filter material is washed with anhydrous ethanol until the resulting filtrate is a colorless and transparent liquid. The washed solid material is then vacuum dried to obtain the flame retardant additive. The vacuum drying temperature is set to 80℃, and the vacuum drying time is set to 12 hours.

[0038] Comparative Example 1: The difference between this example and Example 1 is that this example does not contain an electromagnetic shielding agent.

[0039] Comparative Example 2: This example differs from Example 1 in that it does not contain flame retardant additives.

[0040] Performance testing: The relevant properties of the PMMA composite board material samples provided in Examples 1-3 and Comparative Examples 1-2 were tested respectively, and the test data are recorded in the table below:

[0041]

[0042] By comparing and analyzing the relevant data in the table, it can be seen that the PMMA composite board material prepared by this invention not only has excellent electromagnetic shielding performance but also excellent flame retardant performance, effectively ensuring its grade and quality. This indicates that the electromagnetic shielding PMMA composite board material and its preparation method provided by this invention have a broader market prospect and are more suitable for widespread application.

[0043] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0044] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An electromagnetic shielding PMMA composite sheet material, characterized by, The electromagnetic shielding agent is prepared by the following method: 0.02-0.05 g / mL of an aqueous solution of ferric chloride is added with cobalt chloride with a mass of 0.6-0.7 times that of the ferric chloride, and the mixture is stirred uniformly; then, an aqueous dispersion of graphene oxide is added to the mixture, and ultrasonic dispersion is carried out for 30-40 min; then, the pH of the mixture is adjusted to 10.5-11.5, and 0.3-0.4 times the molar amount of sodium thiosulfate of the ferric chloride is added; the mixture is stirred uniformly, sealed, and heated at a temperature of 130-170 DEG C for 20-40 h; after the reaction is completed, the mixture is naturally cooled to room temperature, and the components of the resulting product are sequentially subjected to centrifugal washing and drying treatment to obtain the electromagnetic shielding agent; the concentration of the graphene oxide in the aqueous dispersion of graphene oxide is 10-20 g / L, and the amount of the aqueous dispersion of graphene oxide is 5-8% of the volume of the mixed solution. The preparation method of the flame-retardant aid includes the following steps: 1,4-diaminobenzene is added to anhydrous ethanol at a dosage of 0.15-0.25 mol / L, and the mixture is stirred under nitrogen protection until the 1,4-diaminobenzene is completely dissolved; then, 0.8-1.2 times the molar amount of phenylphosphonic acid of the 1,4-diaminobenzene is added to the mixture, and the mixture is stirred uniformly and refluxed for 3-5 h; after the reaction is completed, the resulting product is naturally cooled to room temperature, and the stirring reaction is continued at room temperature for 6-10 h; after the reaction is completed, the solid-liquid separation of the reaction product is carried out, and the solid filter cake is washed with anhydrous ethanol until the filtrate is colorless and transparent; and the vacuum drying of the washed solid material is carried out to obtain the flame-retardant aid. The preparation method of the electromagnetic shielding PMMA composite board material includes the following steps: Step one: the raw materials are accurately weighed according to the formula, and then the methyl methacrylate and the initiator are added to a reactor, and the mixture is stirred uniformly and heated in a water bath environment at 80-85 DEG C for 30-40 min; Step two: after the reaction is completed, the resulting product is naturally cooled to room temperature, and then the remaining raw materials are added, and the mixture is stirred uniformly, and the resulting mixed slurry is poured into a corresponding mold, and the electromagnetic shielding PMMA composite board material is obtained after the air bath heating polymerization, cooling and demolding treatment. The initiator is selected from any one of dibenzoyl peroxide, diisobutyryl peroxide and cumyl phenylperoxy neodecanoate.

2. The electromagnetic shielding PMMA composite board material according to claim 1, characterized in that: The temperature of the vacuum drying is set to 70-80 DEG C, and the time of the vacuum drying is set to 10-12 h.

3. The electromagnetic shielding PMMA composite board material according to claim 1, characterized in that: The antistatic agent is selected from one of N-hydroxymethyl acrylamide, N-(2-hydroxypropyl) methacrylamide and N-hydroxymethyl acrylamide.

4. The electromagnetic shielding PMMA composite board material according to claim 1, characterized in that: The lubricant is selected from any one of stearic acid, polyethylene wax, ethylene bis-stearamide and silicone powder.

5. The electromagnetic shielding PMMA composite board material according to claim 1, characterized in that: ​ 6. The electromagnetic shielding PMMA composite sheet material according to claim 1, wherein: The pigments are selected from any one of chrome yellow, black iron oxide, red iron oxide. The pigments are selected from any one of chrome yellow, black iron oxide, red iron oxide.

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