A shielding PVC mesh material and its preparation method

Abstract

This application relates to the field of shielding PVC mesh materials, specifically disclosing a shielding PVC mesh material and its preparation method. A shielding PVC mesh material comprises, sequentially arranged, a mounting layer, a PVC coating, a polyester fiber mesh layer, an adhesive layer, and an electromagnetic shielding layer. The PVC coating contains the following components by weight: 90-100 parts PVC resin; 60-75 parts plasticizer; 3-6 parts stabilizer; 2-4 parts soybean oil; 10-18 parts titanium dioxide; 25-45 parts calcium carbonate; 15-40 parts glass microspheres; 6-15 parts flame retardant; 1-3 parts UV stabilizer; 1-2 parts antioxidant; 2.5-4 parts mildew inhibitor; and 5-10 parts composite polymer. The shielding PVC mesh material of this application can be stably used in high-temperature environments for extended periods and exhibits stable and excellent shielding effects, significantly improving its overall applicability.

Description

Technical Field

[0001] This application relates to the field of shielding PVC mesh materials, and more specifically, it relates to a shielding PVC mesh material and a method for preparing the same. Background Technology

[0002] PVC mesh material is made of two layers of PVC film sandwiched with wire mesh. It has good flexibility, corrosion resistance, wear resistance and bending resistance. It also has the advantages of being waterproof, moisture-proof and UV-resistant, making it one of the most commonly used materials for military tents.

[0003] Military tent materials typically need to shield against electromagnetic waves, cell phone signals, and infrared rays to ensure communication security. Currently, shielding PVC mesh materials with shielding capabilities have the following structure: a polyester fiber mesh is commonly used as the base fabric, with PVC paste coated on both sides of the base fabric to ensure strong adhesion between the PVC layer and the polyester fiber mesh; then, another layer of PVC paste is coated on both sides, followed by a backing treatment to extend outdoor lifespan and provide stain resistance and self-cleaning; finally, adhesive is applied to the front, and an electromagnetic shielding fabric is laminated on top of the adhesive; thus, the resulting shielding PVC mesh material exhibits excellent shielding performance.

[0004] However, when the shielding PVC mesh material is used in a high-temperature environment for a long time, the main PVC component in its structure is prone to aging and degeneration, which in turn causes deformation of the PVC structural layer under the electromagnetic shielding cloth. The stress change caused by this deformation pulls on the electromagnetic shielding cloth, making it easy for tiny gaps to be generated in the electromagnetic shielding cloth, greatly reducing its shielding ability and having a significant adverse impact on the application stability of the shielding PVC mesh material.

[0005] Therefore, there is an urgent need to propose a solution to address the aforementioned technical problems. Summary of the Invention

[0006] In order to enable the shielding PVC mesh material to exert excellent and stable electromagnetic shielding effect when subjected to high temperature for a long time, this application provides a shielding PVC mesh material and its preparation method.

[0007] In a first aspect, this application provides a shielding PVC mesh material, employing the following technical solution:

[0008] A shielding PVC mesh material, comprising a mounting layer, a PVC coating, a polyester fiber mesh layer, a PVC coating, an adhesive layer and an electromagnetic shielding layer arranged sequentially, characterized in that the PVC coating comprises the following components in parts by weight: 90-100 parts of PVC resin.

[0009] Plasticizer 60-75 parts;

[0010] Stabilizer 3-6 parts;

[0011] 2-4 parts soybean oil;

[0012] 10-18 parts titanium dioxide;

[0013] 25-45 parts calcium carbonate;

[0014] 15-40 parts of glass microspheres;

[0015] 6-15 parts flame retardant;

[0016] UV protectant 1-3 parts;

[0017] 1-2 parts antioxidant;

[0018] 2.5-4 parts of antifungal agent;

[0019] 5-10 parts of composite polymer;

[0020] The composite polymer is prepared by the following steps:

[0021] Distilled water and sodium dodecyl sulfate were added to a container and heated and stirred at a temperature of 60-70°C. N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer were added in a weight ratio of (11-13):(18-22):1. After mixing evenly, an initiator was added, and the mixture was heated to 85-95°C and reacted for 4-6 hours. After demulsification with aluminum sulfate, the mixture was filtered, washed and dried to obtain the composite polymer.

[0022] By adopting the above technical solution, a composite polymer is obtained using N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer as the main raw materials. By introducing fluorine into the copolymer backbone, the high-temperature resistance of the PVC coating is significantly improved and the decomposition of PVC is inhibited after blending with PVC resin. Simultaneously, a unique bonding system is formed between the composite polymer and PVC resin. When the shielding PVC mesh material is used in a high-temperature environment for a long time, even if some PVC ages and deforms, the composite polymer acts as an extension backbone to regulate this process. This allows the changes to be resolved within the PVC coating, with minimal transmission to the adhesive layer and minimal impact on the electromagnetic shielding layer. This maintains the excellent stability of the electromagnetic shielding layer structure, resulting in a stable and excellent shielding effect. Therefore, the final shielding PVC mesh material can be stably used in high-temperature environments for extended periods, greatly improving its overall applicability.

[0023] Preferably, the weight ratio of the N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer is 12:20:1.

[0024] By adopting the above technical solution, the composite polymer obtained from the raw materials in the above weight ratio can be stably combined with other component raw materials, and can play a better role in the application process. It forms a relatively stable blending system with PVC, and its internal regulation ability for aging and deformation of some PVC is particularly outstanding. As a result, the shielding PVC mesh material can play a better and more stable shielding effect when used in high temperature environment for a long time.

[0025] Preferably, the PVC coating further comprises 5-8 parts by weight of a zeolite-multi-walled carbon nanotube composite material, which is prepared by the following steps:

[0026] S1. Immerse the multi-walled carbon nanotube raw material in a 65-75% nitric acid solution for 5-10 minutes, take it out, wash it with water and dry it to obtain surface-modified multi-walled carbon nanotubes.

[0027] S2. Zeolite and surface-modified multi-walled carbon nanotubes are mixed and dispersed in an ethanol solution at a weight ratio of (14-26):1, ultrasonically vibrated and mixed evenly, and then dried to obtain zeolite-multi-walled carbon nanotube composite material.

[0028] By employing the above technical solution, multi-walled carbon nanotubes are first surface-modified to achieve a more stable surface structure and pore morphology, and superior dispersibility. Then, they are composited with zeolite, allowing the surface-modified multi-walled carbon nanotubes to be uniformly dispersed within the zeolite pores. Furthermore, a large number of modified multi-walled carbon nanotubes also coat the zeolite surface, resulting in a zeolite-multi-walled carbon nanotube composite material with excellent dispersibility, thermal stability, and surface activity. When this zeolite-multi-walled carbon nanotube composite material is applied to PVC coatings, it strengthens the interfacial bonding between the composite polymer and PVC resin, acting as a connecting point. This reduces the adverse effects of prolonged high temperatures on the PVC resin and enhances the overall effect of the composite polymer, thereby significantly improving the stability of the shielding PVC mesh material in prolonged high-temperature environments.

[0029] Preferably, in step S2, the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 18:1.

[0030] By adopting the above technical solution, the zeolite-multi-walled carbon nanotube composite material obtained by compounding the raw materials in the above weight ratio exhibits excellent and stable performance when applied to PVC coatings, and the resulting shielded PVC mesh material also shows excellent stability in long-term high-temperature environments.

[0031] Preferably, the zeolite has a particle size of 4-6 mm and the multi-walled carbon nanotubes have a diameter of 10-30 nm and a length of 1-2 μm.

[0032] By adopting the above technical solution, the zeolite with the above particle size is easy to disperse during the preparation process and is easily coated by multi-walled carbon nanotubes; and the multi-walled carbon nanotubes of the above size are not easy to agglomerate, are easy to be uniformly dispersed in the pores of the zeolite, and exist stably; thus, the zeolite-multi-walled carbon nanotube composite material obtained in the end can play a relatively stable role in the application process, so that the shielding PVC mesh material exhibits excellent stability when used in a long-term high-temperature environment.

[0033] Preferably, the PVC coating also contains 1-3 parts by weight of basalt fiber.

[0034] By adopting the above technical solution, basalt fiber has excellent high-temperature resistance, and its application in PVC coating can bring excellent high-temperature resistance improvement. At the same time, basalt fiber and zeolite-multi-walled carbon nanotube composite can play an excellent compounding and synergistic role. The mutual entanglement not only exhibits excellent mechanical strength, but also helps the composite polymer to regulate the aging PVC, thereby maintaining the stability of the overall structure of the PVC coating and not easily causing adverse effects on the structure of the electromagnetic shielding layer. This greatly improves the stability of the shielding PVC mesh material in long-term high-temperature environments.

[0035] Preferably, the basalt fiber has a diameter of 0.5-1.5 mm and a length of 4-6 cm.

[0036] By adopting the above technical solution, the basalt fiber of the above specifications can be uniformly dispersed in the mixed system and form an excellent entanglement structure with the zeolite-multi-walled carbon nanotube composite material, thereby exerting a relatively excellent compounding and synergistic effect. In this way, the obtained shielding PVC mesh material can maintain relatively excellent stability in a long-term high-temperature environment.

[0037] Preferably, the plasticizer is one or a combination of several of dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, triphenyl phosphate, and dioctyl sebacate.

[0038] By adopting the above technical solutions, the plasticizers of the above types have good compatibility with PVC resin and can form a relatively stable mixing medium with each other, which is conducive to the full combination of other component raw materials and the exertion of their own functions, and can all obtain high-quality and stable shielding PVC mesh materials.

[0039] Secondly, this application provides a method for preparing a shielding PVC mesh material, which adopts the following technical solution: A method for preparing a shielding PVC mesh material includes the following steps:

[0040] (1) Prepare raw materials containing a mounting layer, a polyester fiber mesh layer, a PVC coating, an adhesive layer and an electromagnetic shielding layer according to the proportions. The PVC coating contains the following components: PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microspheres, flame retardant, UV inhibitor, antioxidant, mildew inhibitor and composite polymer.

[0041] (2) After mixing PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microspheres, flame retardant, UV inhibitor, antioxidant, mildew inhibitor and composite polymer evenly, grind to obtain PVC paste.

[0042] (3) After preheating the polyester fiber mesh layer in step (1), apply PVC paste to both sides. After coagulation and plasticization, apply another layer of PVC paste to the front and back sides respectively. After coagulation and plasticization, a PVC coating is obtained.

[0043] (4) In step (3), glue is applied to the front of the PVC coating, and then an electromagnetic shielding cloth is laminated to form an adhesive layer and an electromagnetic shielding layer; the back is treated with mounting to form a mounting layer; finally, the shielding PVC mesh material is obtained.

[0044] By adopting the above technical solution, the above preparation method is simple to operate and easy to carry out large-scale production. Moreover, each layer of the structure is attached one by one, which not only facilitates quality control during the process, but also ensures the uniformity of each layer of the structure. As a result, the obtained shielding PVC mesh material can play an excellent and stable shielding effect when used in a high-temperature environment for a long time, and the overall quality is excellent.

[0045] In summary, this application has the following beneficial effects:

[0046] 1. This application utilizes a specially prepared composite polymer to form a unique bonding system with PVC resin. This system not only exhibits excellent heat resistance but also adaptively adjusts to the aging and deformation of some PVC components. This ensures that the PVC coating maintains a relatively stable overall structure and is less likely to adversely affect the structure of the electromagnetic shielding layer. Consequently, the resulting shielding PVC mesh material can be stably used in high-temperature environments for extended periods, greatly improving its overall applicability.

[0047] 2. When the obtained zeolite-multi-walled carbon nanotube composite material is applied to PVC coating, it can strengthen the interfacial bonding strength between the composite polymer and PVC resin, and act as a connection point, thereby strengthening the composite polymer's inhibition and regulation of PVC aging and deformation. This helps to ensure the structural integrity of the electromagnetic shielding layer and greatly improves the stability of the shielding PVC mesh material in a long-term high-temperature environment.

[0048] 3. Based on the use of zeolite-multi-walled carbon nanotube composite material, this application adds basalt fiber. By utilizing the synergistic effect of the two, the high temperature resistance of the PVC coating and its self-regulation performance after partial aging and deformation can be greatly improved. This is conducive to maintaining the stability of the overall structure of the PVC coating, making it less likely that the aging of some PVC will have an adverse effect on the structure of the electromagnetic shielding layer. In this way, the stability of the shielding PVC mesh material in long-term high-temperature environments can be greatly improved. Detailed Implementation

[0049] The present application will be further described in detail below with reference to the embodiments.

[0050] Unless otherwise specified, all raw materials used in the preparation examples and embodiments of this application are commercially available.

[0051] The hexafluoropropylene trimer was purchased from Zhongshan Dixin Chemical Co., Ltd., industrial grade, CAS number 6792-31-0;

[0052] The zeolite was supplied by Zhuochuan Mineral Products Processing Plant in Lingshou County;

[0053] The multi-walled carbon nanotubes were supplied by Guangzhou Hongwu Materials Technology Co., Ltd., with the grade HWP-C930.

[0054] The basalt fiber was provided by Shandong Hengtai New Material Technology Co., Ltd.

[0055] The acrylic adhesive was purchased from 3M DP8805NS low-odor acrylic adhesive.

[0056] The electromagnetic shielding layer was purchased from Hefei Aijia Anti-radiation Technology Co., Ltd., and its electromagnetic shielding conductive cloth is 0.5mm thick with a specification of 75g / m². 2 ;

[0057] The stabilizer was purchased from Jiashan Sanyi New Materials Co., Ltd. as SZ963 calcium-zinc stabilizer.

[0058] The flame retardant was purchased from Suzhou Jiayi Chemical Co., Ltd. as K-609P;

[0059] The UV stabilizer was purchased from UV-326, a light stabilizer.

[0060] The antioxidant 1098 was purchased from Changzhou Youfeng Chemical Co., Ltd.

[0061] The antifungal agent was purchased from Foshan Liyuan Chemical Co., Ltd. as JL-1086 antibacterial and antifungal powder.

[0062] Preparation examples of raw materials and / or intermediates

[0063] Preparation Example 1

[0064] A composite polymer is prepared by the following steps:

[0065] Distilled water and sodium dodecyl sulfate were added to a container and heated and stirred at 65°C. N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer were added in a weight ratio of 12:20:1. After mixing evenly, an initiator was added, and the mixture was heated to 90°C and reacted for 5 hours. After demulsification with aluminum sulfate, the mixture was filtered, washed and dried to obtain the composite polymer.

[0066] Note: In the above operation, a 10% SDS solution was obtained by dissolving 10g of sodium dodecyl sulfate in 0.9L of distilled water; the amount of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer added accounted for 60% of the weight of the SDS solution; the initiator was potassium persulfate, and the amount added was 0.3% of the total weight of the mixture; a 0.05% aluminum sulfate solution was used for demulsification; and methanol was used for washing.

[0067] Preparation Example 2

[0068] A composite polymer, differing from Preparation Example 1, was prepared by the following steps: distilled water and sodium dodecyl sulfate were added to a container and heated and stirred at 60°C. N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer were added in a weight ratio of 12:20:1. After mixing evenly, an initiator was added, and the mixture was heated to 85°C and reacted for 4 hours. After demulsification with aluminum sulfate, the mixture was filtered, washed, and dried to obtain the composite polymer.

[0069] Preparation Example 3

[0070] A composite polymer, differing from Preparation Example 1, was prepared by the following steps: distilled water and sodium dodecyl sulfate were added to a container and heated and stirred at 70°C. N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer were added in a weight ratio of 12:20:1. After mixing thoroughly, an initiator was added, and the mixture was heated to 95°C and reacted for 6 hours. After demulsification with aluminum sulfate, the mixture was filtered, washed, and dried to obtain the composite polymer.

[0071] Preparation Example 4

[0072] A composite polymer, which differs from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 11:18:1.

[0073] Preparation Example 5

[0074] A composite polymer, which differs from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 13:22:1.

[0075] Preparation Example 6

[0076] A composite polymer, which differs from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 10:17:1.

[0077] Preparation Example 7

[0078] A composite polymer, which differs from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 14:23:1.

[0079] Preparation Example 8

[0080] A zeolite-multi-walled carbon nanotube composite material is prepared by the following steps:

[0081] S1. Immerse the multi-walled carbon nanotube raw material in a 70% nitric acid solution for 7.5 min, take it out, wash it with water and dry it to obtain surface-modified multi-walled carbon nanotubes.

[0082] S2. Zeolite and surface-modified multi-walled carbon nanotubes are mixed and dispersed in 5 times their weight of ethanol solution at a weight ratio of 18:1. The mixture is ultrasonically vibrated and mixed evenly. After drying, zeolite-multi-walled carbon nanotube composite material is obtained.

[0083] Note: In step S2, the concentration of the ethanol solution is 60%; the ultrasonic oscillation power is 600W and the time is 10min; the particle size of the zeolite is 5mm, and the diameter of the multi-walled carbon nanotubes is 20nm and the length is 1.5μm.

[0084] Preparation Example 9

[0085] A zeolite-multi-walled carbon nanotube composite material differs from preparation example 8 in that step S1 is specifically set as follows: the multi-walled carbon nanotube raw material is immersed in a 65% nitric acid solution for 10 minutes, then taken out, washed with water and dried to obtain surface-modified multi-walled carbon nanotubes.

[0086] Preparation Example 10

[0087] A zeolite-multi-walled carbon nanotube composite material differs from preparation example 8 in that step S1 is specifically set as follows: the multi-walled carbon nanotube raw material is immersed in a 75% nitric acid solution for 5 minutes, and then washed and dried to obtain surface-modified multi-walled carbon nanotubes.

[0088] Preparation Example 11

[0089] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the zeolite has a particle size of 4 mm, and the multi-walled carbon nanotubes have a diameter of 10 nm and a length of 1 μm.

[0090] Preparation Example 12

[0091] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the zeolite has a particle size of 6 mm, and the multi-walled carbon nanotubes have a diameter of 30 nm and a length of 2 μm.

[0092] Preparation Example 13

[0093] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 14:1.

[0094] Preparation Example 14

[0095] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 26:1.

[0096] Preparation Example 15

[0097] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 20:1.

[0098] Preparation Example 16

[0099] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 13:1.

[0100] Preparation Example 17

[0101] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 27:1.

[0102] Preparation Example 18

[0103] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the zeolite has a particle size of 3.5 mm, and the multi-walled carbon nanotubes have a diameter of 8 nm and a length of 0.8 μm.

[0104] Preparation Example 19

[0105] A zeolite-multi-walled carbon nanotube composite material differs from Preparation Example 8 in that the zeolite has a particle size of 6.5 mm, and the multi-walled carbon nanotubes have a diameter of 32 nm and a length of 2.2 μm.

[0106] Example

[0107] Example 1

[0108] A shielding PVC mesh material comprises, in sequence, a mounting layer, a PVC coating, a polyester fiber mesh layer, another PVC coating, an adhesive layer, and an electromagnetic shielding layer. The raw materials and their corresponding weights for each component of the PVC coating are shown in Table 1. The material is prepared through the following steps:

[0109] (1) Prepare raw materials containing a mounting layer, a polyester fiber mesh layer, a PVC coating, an adhesive layer and an electromagnetic shielding layer according to the proportions. The PVC coating contains the following components: PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microspheres, flame retardant, UV inhibitor, antioxidant, mildew inhibitor and composite polymer.

[0110] (2) After mixing PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microspheres, flame retardant, UV inhibitor, antioxidant, mildew inhibitor and composite polymer evenly, grind to obtain PVC paste.

[0111] (3) After preheating the polyester fiber mesh layer in step (1), apply PVC paste to both sides. After coagulation and plasticization, the plasticization temperature is 145℃ and the time is 15min. Then apply another layer of PVC paste to the front and back sides. After coagulation and plasticization, the plasticization temperature is 160℃ and the time is 10min to obtain the PVC coating.

[0112] (4) In step (3), glue is applied to the front of the PVC coating, and then an electromagnetic shielding cloth is laminated to form an adhesive layer and an electromagnetic shielding layer; the back is treated with mounting to form a mounting layer; finally, the shielding PVC mesh material is obtained.

[0113] Note: In the above operations, the adhesive layer is acrylic glue, the mounting layer is PVF film; the polyester fiber mesh layer is 0.2 mm, the inner PVC coating layer is 0.3 mm, the outer PVC coating layer is 0.3 mm, the mounting layer is 0.1 mm, and the adhesive layer is 0.1 mm; the composite polymer used was obtained from Preparation Example 1.

[0114] Example 2-3

[0115] A shielding PVC mesh material differs from Example 1 in that the raw materials of each component of the PVC coating and their corresponding weights are shown in Table 1.

[0116] Table 1. Raw materials and their weight parts (kg / part) for each component of the PVC coating in Examples 1-3

[0117]

[0118]

[0119] Example 4

[0120] A shielding PVC mesh material, which differs from Example 1 in that the composite polymer used is obtained from Preparation Example 2.

[0121] Example 5

[0122] A shielding PVC mesh material, which differs from Example 1 in that the composite polymer used is obtained from Preparation Example 3.

[0123] Example 6

[0124] A shielding PVC mesh material, which differs from Example 1 in that the composite polymer used is obtained from Preparation Example 4.

[0125] Example 7

[0126] A shielding PVC mesh material, which differs from Example 1 in that the composite polymer used is obtained from Preparation Example 5.

[0127] Example 8

[0128] A shielding PVC mesh material, which differs from Example 1 in that the composite polymer used is obtained from Preparation Example 6.

[0129] Example 9

[0130] A shielding PVC mesh material, which differs from Example 1 in that the composite polymer used is obtained from Preparation Example 7.

[0131] Example 10

[0132] A shielding PVC mesh material differs from Example 1 in that the PVC coating also contains 6.5 parts by weight of zeolite-multi-walled carbon nanotube composite material; the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 8.

[0133] Example 11

[0134] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is added in 5 parts by weight.

[0135] Example 12

[0136] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is added in 8 parts by weight.

[0137] Example 13

[0138] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 9.

[0139] Example 14

[0140] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 10.

[0141] Example 15

[0142] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 11.

[0143] Example 16

[0144] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 12.

[0145] Example 17

[0146] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 13.

[0147] Example 18

[0148] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 14.

[0149] Example 19

[0150] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 15.

[0151] Example 20

[0152] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 16.

[0153] Example 21

[0154] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 17.

[0155] Example 22

[0156] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 18.

[0157] Example 23

[0158] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material was obtained in Preparation Example 19.

[0159] Example 24

[0160] A shielding PVC mesh material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is replaced by zeolite.

[0161] Example 25

[0162] A shielding PVC mesh material differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite is replaced by multi-walled carbon nanotubes.

[0163] Example 26

[0164] A shielding PVC mesh material differs from Example 10 in that the PVC coating also contains 2 parts by weight of basalt fiber, the basalt fiber having a diameter of 1 mm and a length of 5 cm.

[0165] Example 27

[0166] A shielding PVC mesh material, which differs from Example 26 in that the basalt fiber added is 1 part by weight.

[0167] Example 28

[0168] A shielding PVC mesh material, which differs from Example 26 in that basalt fiber is added in 3 parts by weight.

[0169] Example 29

[0170] A type of shielding PVC mesh material, which differs from Example 26 in that the basalt fibers have a diameter of 0.5 mm and a length of 4 cm.

[0171] Example 30

[0172] A type of shielding PVC mesh material, which differs from Example 26 in that the basalt fibers have a diameter of 1.5 mm and a length of 6 cm.

[0173] Example 31

[0174] A type of shielding PVC mesh material, which differs from Example 26 in that the basalt fibers have a diameter of 0.4 mm and a length of 3.5 cm.

[0175] Example 32

[0176] A shielding PVC mesh material, which differs from Example 26 in that the basalt fibers have a diameter of 1.6 mm and a length of 6.5 cm.

[0177] Example 33

[0178] A shielding PVC mesh material, which differs from Example 26 in that the PVC coating does not contain zeolite-multi-walled carbon nanotube composite material.

[0179] Comparative Example

[0180] Comparative Example 1

[0181] A shielding PVC mesh material, which differs from Example 1 in that the PVC coating does not contain composite polymers.

[0182] Comparative Example 2

[0183] A shielding PVC mesh material, which differs from Example 10 in that the PVC coating does not contain composite polymers.

[0184] Performance testing test samples: The shielding PVC mesh material obtained in Examples 1-33 was used as test samples 1-33, and the shielding PVC mesh material obtained in Comparative Examples 1-2 was used as control samples 1-2.

[0185] Test method: The electromagnetic shielding effectiveness of test sample 1-33 and control sample 1-2 was measured according to standard SJ20524-1995 "Method for Measurement of Shielding Effectiveness of Materials", and recorded as the initial electromagnetic shielding effectiveness. Then, test sample 1-33 and control sample 1-2 were placed in a high-altitude simulated high-temperature environment with a temperature of 48℃ and a relative humidity of 30% for 7 days. After that, the electromagnetic shielding effectiveness of test sample 1-33 and control sample 1-2 was measured in the same way and recorded as the post-test electromagnetic shielding effectiveness. Finally, the electromagnetic shielding effectiveness loss rate of each sample was calculated, and the electromagnetic shielding effectiveness loss rate (%) = (initial electromagnetic shielding effectiveness - post-test electromagnetic shielding effectiveness) / initial electromagnetic shielding effectiveness, and recorded in Table 2 below.

[0186] Table 2 Test results of test samples 1-33 and control samples 1-2

[0187]

[0188]

[0189] As can be seen from Examples 1-3 and Comparative Example 1, and Table 2, by applying the specially prepared composite polymer to the PVC coating, the damage to the electromagnetic shielding layer caused by PVC aging and deformation can be greatly reduced. Therefore, in a long-term high-temperature environment, the electromagnetic shielding effectiveness loss rate measured by the shielding PVC mesh material is significantly lower, and the application stability is outstanding.

[0190] Combining Examples 1 and 6-9 with Table 2, it can be seen that the composite polymer obtained by polymerizing N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer in a weight ratio of (11-13):(18-22):1) exhibits stable performance during application, resulting in a low electromagnetic shielding effectiveness loss rate for the shielded PVC mesh material. Specifically, when the weight ratio of N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer is 12:20:1, the shielded PVC mesh material demonstrates excellent stability in prolonged high-temperature environments. However, when the weight ratio of the above raw materials exceeds this range, the application effect of the composite polymer is significantly reduced, showing a marked increase in the electromagnetic shielding effectiveness loss rate. Therefore, the weight ratio of the three raw materials is particularly important for obtaining a stable and high-performance composite polymer.

[0191] Combining Examples 1 and 10-14 with Table 2, it can be seen that when the zeolite-multi-walled carbon nanotube composite is applied to the PVC coating, it can further improve the stability of the PVC coating under prolonged high temperatures, and further reduce the electromagnetic shielding effectiveness loss rate measured for the shielded PVC mesh material. Furthermore, combining Comparative Example 2 with Table 2, it can be seen that if the zeolite-multi-walled carbon nanotube composite is added to the PVC coating without the composite polymer, the improvement effect brought by the zeolite-multi-walled carbon nanotube composite is not as excellent as in Example 10. This indicates that the composite polymer and the zeolite-multi-walled carbon nanotube composite have a synergistic effect, and their mutual cooperation can greatly improve the stability of the shielded PVC mesh material in a prolonged high-temperature environment.

[0192] Combining Examples 10 and 17-21 with Table 2, it can be seen that in the preparation of zeolite-multi-walled carbon nanotube composites, a weight ratio of zeolite to surface-modified multi-walled carbon nanotubes of (14-26):1 yields a high-quality and stable zeolite-multi-walled carbon nanotube composite. When the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 18:1, the zeolite-multi-walled carbon nanotube composite significantly improves the structural stability of the PVC coating, thus making the electromagnetic shielding layer less susceptible to damage. The measured electromagnetic shielding effectiveness loss rate of the shielded PVC mesh material is relatively low. However, when the ratio exceeds the above range, the application effect of the zeolite-multi-walled carbon nanotube composite in the PVC coating is significantly reduced.

[0193] Based on Examples 10, 15-16, and 22-23, and in conjunction with Table 2, it can be seen that a zeolite particle size of 4-6 mm and a multi-walled carbon nanotube diameter of 10-30 nm and a length of 1-2 μm ensure that the zeolite-multi-walled carbon nanotube composite material exhibits excellent and stable performance when applied in PVC coatings. However, exceeding these specifications leads to an increase in the measured electromagnetic shielding effectiveness loss rate of the shielded PVC mesh material. It is speculated that the agglomeration or inability to stretch the raw materials results in poor adhesion of the morphology and structure of the zeolite-multi-walled carbon nanotube composite material to the PVC coating.

[0194] Based on Examples 10 and 24-25 and Table 2, it can be seen that adding zeolite or multi-walled carbon nanotubes alone to PVC coatings has limited effect on improving the stability of PVC coatings in long-term high-temperature environments, and the improvement effect is far less than that of zeolite-multi-walled carbon nanotube composites. This shows that the zeolite-multi-walled carbon nanotube composite prepared from zeolite and multi-walled carbon nanotubes has a significant effect on improving the stability of shielded PVC mesh materials in long-term high-temperature environments.

[0195] Combining Examples 10 and 26-28 with Table 2, it can be seen that the addition of basalt fiber can further improve the high-temperature resistance of the PVC coating, making the electromagnetic shielding layer less susceptible to damage. The measured electromagnetic shielding effectiveness loss rate of the shielded PVC mesh material is also further reduced. Furthermore, combining Examples 29-32 with Table 2, it can be seen that the diameter of the basalt fiber is 0.5-1.5 mm and the length is 4-6 cm, which allows it to exert an excellent and stable improvement effect during application. However, when the specifications exceed these, the improvement effect is not ideal. Combining Example 33 with Table 2, it can be seen that when basalt fiber is used in a PVC coating without zeolite-multi-walled carbon nanotube composite, the improvement effect brought by basalt fiber is far less than that of Example 26. This indicates that basalt fiber and zeolite-multi-walled carbon nanotube composite have a synergistic effect, and their mutual cooperation can greatly improve the stability of the shielded PVC mesh material in a long-term high-temperature environment.

[0196] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A shielding PVC mesh material, characterized in that, The material comprises, in sequence, a mounting layer, a PVC coating, a polyester fiber mesh layer, another PVC coating, an adhesive layer, and an electromagnetic shielding layer, characterized in that the PVC coating contains the following components in parts by weight: 90-100 parts of PVC resin; Plasticizer 60-75 parts; Stabilizer 3-6 parts; 2-4 parts soybean oil; 10-18 parts titanium dioxide; 25-45 parts calcium carbonate; 15-40 parts of glass microspheres; 6-15 parts flame retardant; UV protectant 1-3 parts; 1-2 parts antioxidant; 2.5-4 parts of antifungal agent; 5-10 parts of composite polymer; The composite polymer is prepared by the following steps: Distilled water and sodium dodecyl sulfate were added to a container and heated and stirred at a temperature of 60-70°C. N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer were added in a weight ratio of (11-13):(18-22):

1. After mixing evenly, an initiator was added and the temperature was raised to 85-95°C for 4-6 hours. After demulsification with aluminum sulfate, the mixture was filtered, washed and dried to obtain the composite polymer. 5-8 parts of zeolite-multi-walled carbon nanotube composite material; The zeolite-multi-walled carbon nanotube composite material was prepared through the following steps: S1. Immerse the multi-walled carbon nanotube raw material in a 65-75% nitric acid solution for 5-10 minutes, take it out, wash it with water and dry it to obtain surface-modified multi-walled carbon nanotubes. S2. Zeolite and surface-modified multi-walled carbon nanotubes are mixed and dispersed in an ethanol solution at a weight ratio of (14-26):

1. The mixture is ultrasonically vibrated and mixed evenly. After drying, the zeolite-multi-walled carbon nanotube composite material can be obtained. Basalt fiber 1-3 parts.

2. The shielding PVC mesh material according to claim 1, characterized in that: The weight ratio of the N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer is 12:20:

1.

3. The shielding PVC mesh material according to claim 1, characterized in that: In step S2, the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 18:

1.

4. The shielding PVC mesh material according to claim 1, characterized in that: The zeolite has a particle size of 4-6 mm, and the multi-walled carbon nanotubes have a diameter of 10-30 nm and a length of 1-2 μm.

5. The shielding PVC mesh material according to claim 1, characterized in that: The basalt fibers have a diameter of 0.5-1.5 mm and a length of 4-6 cm.

6. The shielding PVC mesh material according to claim 1, characterized in that: The plasticizer is one or a combination of several of the following: dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, triphenyl phosphate, and dioctyl sebacate.

7. The method for preparing the shielding PVC mesh material according to claim 1, characterized in that: Includes the following steps: (1) Prepare raw materials including a mounting layer, a polyester fiber mesh layer, a PVC coating, an adhesive layer and an electromagnetic shielding layer according to the proportions. The PVC coating includes the following components: PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microspheres, flame retardant, UV stabilizer, antioxidant, mildew inhibitor, composite polymer, zeolite-multi-walled carbon nanotube composite and basalt fiber. (2) PVC paste is prepared by mixing PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microspheres, flame retardant, UV inhibitor, antioxidant, mildew inhibitor, composite polymer, zeolite-multi-walled carbon nanotube composite material and basalt fiber evenly and then grinding them. (3) After preheating the polyester fiber mesh layer in step (1), apply PVC paste to both sides. After coagulation and plasticization, apply another layer of PVC paste to the front and back sides respectively. After coagulation and plasticization, a PVC coating is obtained. (4) In step (3), glue is applied to the front of the PVC coating, and then an electromagnetic shielding cloth is laminated to form an adhesive layer and an electromagnetic shielding layer; the back is treated with mounting to form a mounting layer; finally, the shielding PVC mesh material is obtained.

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