Shielding PVC mesh-sandwiched material and preparation method therefor

Abstract

Disclosed in the present application are a shielding PVC mesh-sandwiched material and a preparation method therefor. The shielding PVC mesh-sandwiched material comprises a mounting layer, a PVC coating, a polyester fiber mesh cloth layer, a PVC coating, a bonding layer and an electromagnetic shielding layer which are sequentially arranged, and the PVC coating comprises the following components in parts by weight: 90-100 parts of a PVC resin; 60-75 parts of a plasticizer; 3-6 parts of a stabilizer; 2-4 parts of soybean oil; 10-18 parts of titanium dioxide; 25-45 parts of calcium carbonate; 15-40 parts of glass beads; 6-15 parts of a flame retardant; 1-3 parts of an anti-UV agent; 1-2 parts of an antioxidant; 2.5-4 parts of a mold inhibitor; and 5-10 parts of a composite polymer. The shielding PVC mesh-sandwiched material of the present application can be stably used in a high-temperature environment for a long time and can have a stable and excellent shielding effect, thereby greatly improving the overall applicability.

Description

A shielding PVC mesh material and its preparation method Technical Field

[0001] The present application relates to the field of shielding PVC mesh materials, and more specifically, to a shielding PVC mesh material and a preparation method thereof. Background Art

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

[0003] Military tent materials are often required to shield electromagnetic waves, mobile phone signals, and infrared rays to ensure communication security. Currently, shielded PVC mesh materials with this function include the following structure: a polyester fiber mesh is often used as the base fabric in the middle, with PVC paste coated on both sides to ensure the bonding strength between the PVC layer and the polyester fiber mesh. A further layer of PVC paste is then applied to both the front and back sides, followed by a mounting treatment on the back to extend the outdoor service life and provide anti-fouling and self-cleaning properties. Finally, glue is applied to the front, and a layer of electromagnetic shielding fabric is laminated on top of the glue. The resulting shielded PVC mesh material exhibits excellent shielding effectiveness.

[0004] However, when the shielding PVC mesh material is used for a long time in a high-temperature environment, 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 the electromagnetic shielding cloth, causing tiny gaps in the electromagnetic shielding cloth, greatly reducing the shielding ability, and bringing a greater adverse effect on the application stability of the shielding PVC mesh material.

[0005] Therefore, it is urgent to propose a solution to solve the above technical problems.

[0006] Summary of the Invention

[0007] In order to enable the shielding PVC mesh material to exert an excellent and stable electromagnetic shielding effect when it is subjected to high temperature for a long time, the present application provides a shielding PVC mesh material and a preparation method thereof.

[0008] In the first aspect, the present application provides a shielding PVC mesh material, which adopts the following technical solution:

[0009] A shielding PVC mesh material comprises a mounting layer, a PVC coating, a polyester fiber mesh layer, a PVC coating, an adhesive layer, and an electromagnetic shielding layer, wherein the PVC coating comprises the following components in parts by weight:

[0010] 90-100 parts of PVC resin;

[0011] 60-75 parts of plasticizer;

[0012] 3-6 parts of stabilizer;

[0013] 2-4 parts soybean oil;

[0014] 10-18 parts of titanium dioxide;

[0015] 25-45 parts of calcium carbonate;

[0016] 15-40 parts of glass beads;

[0017] 6-15 parts of flame retardant;

[0018] 1-3 parts of anti-UV agent;

[0019] 1-2 parts antioxidant;

[0020] 2.5-4 parts of antifungal agent;

[0021] 5-10 parts of composite polymer;

[0022] The composite polymer is prepared by the following steps:

[0023] Distilled water and sodium lauryl sulfate are added to a container and heated with stirring at a heating temperature of 60-70°C. N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer are added in a weight ratio of (11-13):(18-22):1. After mixing evenly, an initiator is added. The temperature is raised to 85-95°C and the reaction is carried out for 4-6 hours. The emulsion is broken with aluminum sulfate, filtered, washed and dried to obtain a composite polymer.

[0024] By adopting the above technical solution, a composite polymer obtained using N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer as the main raw materials introduces fluorine into the copolymer backbone. After blending with PVC resin, it can greatly improve the high-temperature resistance of the PVC coating and inhibit the decomposition of PVC. At the same time, the composite polymer and PVC resin can form a unique bonding system. When the shielding PVC mesh material is used in high-temperature environments for a long time, even if some PVC ages and deforms, the composite polymer can act as an extended skeleton to adjust the process, so that this change is eliminated within the PVC coating and is basically not transmitted to the contacting adhesive layer. It is also unlikely to affect the electromagnetic shielding layer. In turn, the structure of the electromagnetic shielding layer maintains relatively excellent stability and exerts a stable and excellent shielding effect. In this way, the resulting shielding PVC mesh material can be used stably and for a long time in high-temperature environments, greatly improving its overall applicability.

[0025] Preferably, the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 12:20:1.

[0026] 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, can play a relatively excellent role in the application process, and form a relatively stable blending system with PVC. In particular, the internal regulation ability for aging and deformation of some PVC is more outstanding, thereby enabling the shielding PVC mesh material to exert a relatively excellent and stable shielding effect when used in a high-temperature environment for a long time.

[0027] Preferably, the components of the PVC coating are further added with 5-8 parts by weight of a zeolite-multi-walled carbon nanotube composite, and the zeolite-multi-walled carbon nanotube composite is prepared by the following steps:

[0028] S1, taking a multi-walled carbon nanotube raw material and immersing it in a nitric acid solution with a concentration of 65-75% for 5-10 minutes, taking it out and washing it with water and drying it to obtain surface-modified multi-walled carbon nanotubes;

[0029] S2. Zeolite and surface-modified multi-walled carbon nanotubes are dispersed in an ethanol solution at a weight ratio of (14-26):1, mixed and evenly mixed by ultrasonic vibration, and dried to obtain a zeolite-multi-walled carbon nanotube composite.

[0030] By adopting the above technical solution, the multi-walled carbon nanotubes are first surface-modified to make the surface structure and pore morphology more stable and the dispersibility more excellent; then they are compounded with zeolite, so that the surface-modified multi-walled carbon nanotubes are evenly dispersed in the zeolite pores, and a large number of modified multi-walled carbon nanotubes are also coated on the zeolite surface, thereby obtaining a zeolite-multi-walled carbon nanotube composite material with excellent dispersibility and thermal stability and excellent surface activity. 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 the PVC resin and act as a connection point, which can not only reduce the adverse effects of long-term high temperature on the PVC resin, but also strengthen the overall effect of the composite polymer, thereby greatly improving the stability of the shielding PVC mesh material in a long-term high temperature environment.

[0031] Preferably, in step S2, the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 18:1.

[0032] By adopting the above technical solution, the zeolite-multi-walled carbon nanotube composite obtained by compounding the raw materials in the above weight ratio has excellent and stable effects when applied to PVC coating, and the obtained shielding PVC mesh material also has excellent stability in a long-term high-temperature environment.

[0033] Preferably, the particle size of the zeolite is 4-6 mm, the diameter of the multi-walled carbon nanotube is 10-30 nm, and the length is 1-2 μm.

[0034] By adopting the above technical solution, the zeolite of the above particle size specifications is easy to disperse during the preparation process and is easy to be coated with multi-walled carbon nanotubes; and the multi-walled carbon nanotubes of the above specifications are not easy to agglomerate, and are easy to be evenly dispersed in the pores of the zeolite and exist stably; in this way, the zeolite-multi-walled carbon nanotube composite material finally obtained can exert a relatively stable effect during the application process, so that the shielding PVC mesh material exhibits relatively excellent stability when used in a long-term high-temperature environment.

[0035] Preferably, 1-3 parts by weight of basalt fiber are also added to the components of the PVC coating.

[0036] 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 performance; at the same time, basalt fiber and zeolite-multi-walled carbon nanotube composites can play an excellent compounding and synergistic role. The entanglement between them can not only show excellent mechanical strength, but also assist the composite polymer in regulating the aging of PVC, thereby maintaining the stability of the overall structure of the PVC coating, and is not easy to have an adverse effect on the structure of the electromagnetic shielding layer, thereby greatly improving the stability of the shielding PVC mesh material in long-term high-temperature environments.

[0037] Preferably, the basalt fiber has a diameter of 0.5-1.5 mm and a length of 4-6 cm.

[0038] By adopting the above technical solution, the basalt fiber of the above specifications can be evenly dispersed in the mixed system and form an excellent entanglement structure with the zeolite-multi-walled carbon nanotube composite, 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.

[0039] Preferably, the plasticizer is one or a combination of dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, triphenyl phosphate and dioctyl sebacate.

[0040] By adopting the above technical solution, the above types of plasticizers have good compatibility with PVC resin and can form a relatively stable mixed medium with each other, which is conducive to the full combination of other component raw materials and their own effects, and can obtain high-quality and stable shielding PVC mesh materials.

[0041] In a second aspect, the present application provides a method for preparing a shielding PVC mesh material, which adopts the following technical solution:

[0042] A method for preparing a shielding PVC mesh material comprises the following steps:

[0043] (1) preparing raw materials including a mounting layer, a polyester fiber mesh layer, a PVC coating, an adhesive layer, and an electromagnetic shielding layer according to a ratio, wherein the PVC coating comprises the following components: PVC resin, a plasticizer, a stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microbeads, a flame retardant, an anti-ultraviolet (UV) agent, an antioxidant, a mildew inhibitor, and a composite polymer;

[0044] (2) PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass beads, flame retardant, anti-UV agent, antioxidant, mildew inhibitor and composite polymer are mixed and then ground to obtain PVC paste;

[0045] (3) After preheating the polyester fiber mesh layer in step (1), PVC paste is applied on both sides, and after coagulation and plasticization, a layer of PVC paste is applied on the front and back sides respectively, and after coagulation and plasticization, a PVC coating is obtained;

[0046] (4) In step (3), glue is applied to the front side of the PVC coating, and then a layer of electromagnetic shielding cloth is compounded to form an adhesive layer and an electromagnetic shielding layer; the back side is subjected to mounting treatment to form a mounting layer; and finally, a shielding PVC mesh material is obtained.

[0047] By adopting the above technical solution, the above preparation method is simple to operate and convenient for large-scale production, and each layer structure is attached and processed one by one, which is not only conducive to quality control during the process, but also can ensure the uniformity of each layer structure, thereby enabling the obtained shielding PVC mesh material to exert excellent and stable shielding effect when used in a long-term high-temperature environment, and the overall quality is relatively excellent.

[0048] In summary, this application has the following beneficial effects:

[0049] 1. This application utilizes a specially prepared composite polymer to form a unique bonding system with PVC resin. This not only exhibits excellent heat resistance, but also can adaptively adjust to the aging deformation of some PVC layers, allowing the PVC coating to maintain a relatively stable overall structure and less likely to adversely affect the structure of the electromagnetic shielding layer. This allows the resulting shielded PVC mesh material to be stably used in high-temperature environments for a long period of time, greatly improving its overall applicability.

[0050] 2. When the zeolite-multi-walled carbon nanotube composite obtained in this application is applied to a PVC coating, it can strengthen the interfacial bonding strength between the composite polymer and the PVC resin and act as a connection point, thereby enhancing the composite polymer's ability to inhibit and regulate aging and deformation of the PVC, thereby facilitating the structural integrity of the electromagnetic shielding layer and greatly improving the stability of the PVC sandwich shielding material in a long-term high-temperature environment.

[0051] 3. This application uses zeolite-multi-walled carbon nanotube composites and adds basalt fiber. By utilizing the synergistic effect of the combination of the two, it can greatly improve the high-temperature resistance of the PVC coating and the self-regulation performance after partial aging and deformation. It is beneficial to maintain the stability of the overall structure of the PVC coating, so that the aging of some PVC is less likely to have an adverse effect on the structure of the electromagnetic shielding layer, thereby greatly improving the stability of the shielding PVC mesh material in long-term high-temperature environments. DETAILED DESCRIPTION

[0052] The present application is further described in detail below with reference to the embodiments.

[0053] Unless otherwise specified, the raw materials used in the preparation examples and embodiments of this application are commercially available:

[0054] Hexafluoropropylene trimer was purchased from Zhongshan Dixin Chemical Co., Ltd., industrial grade, CAS number 6792-31-0;

[0055] Zeolite was provided by Lingshou County Zhuochuan Mineral Products Processing Plant;

[0056] Multi-walled carbon nanotubes were provided by Guangzhou Hongwu Material Technology Co., Ltd., with the brand name HWP-C930;

[0057] Basalt fiber was provided by Shandong Hengtai New Material Technology Co., Ltd.;

[0058] Acrylic glue was purchased as 3MDP8805NS low odor acrylic adhesive;

[0059] The electromagnetic shielding layer was purchased from Hefei Aijia Anti-Radiation Technology Co., Ltd. The electromagnetic shielding conductive cloth has a thickness of 0.5 mm and a specification of 75 g / m 2 ;

[0060] The stabilizer was purchased from Jiashan Sanyi New Materials Co., Ltd. SZ963 calcium zinc stabilizer;

[0061] Flame retardant K-609P was purchased from Suzhou Jiayi Chemical Co., Ltd.;

[0062] The anti-UV agent was purchased as light stabilizer UV-326;

[0063] Antioxidant 1098 was purchased from Changzhou Youfeng Chemical Co., Ltd.

[0064] The antifungal agent was purchased from JL-1086 antibacterial and antifungal powder of Foshan Liyuan Chemical Co., Ltd.

[0065] Preparation examples of raw materials and / or intermediates

[0066] Preparation Example 1

[0067] A composite polymer is prepared by the following steps:

[0068] Distilled water and sodium lauryl sulfate were added to a container and heated with stirring at 65°C. N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer were added in a weight ratio of 12:20:1, mixed evenly, and then an initiator was added. The temperature was raised to 90°C and the reaction was carried out for 5 hours. The emulsion was broken with aluminum sulfate, filtered, washed, and dried to obtain a composite polymer.

[0069] Note: In the above operation, 10 g of sodium dodecyl sulfate was dissolved in 0.9 L of distilled water to obtain a 10% SDS solution; the amount of N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer added was 60% by weight of the SDS solution; the initiator was potassium persulfate, and the amount added was 0.3% by weight of the total mixture; a 0.05% aluminum sulfate solution was used for demulsification; and methanol was used for washing.

[0070] Preparation Example 2

[0071] A composite polymer, which differs from Preparation Example 1 in that it is prepared by the following steps: adding distilled water and sodium lauryl sulfate to a container and heating and stirring at a heating temperature of 60°C, adding N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer in a weight ratio of 12:20:1, mixing evenly, adding an initiator, heating to 85°C and reacting for 4 hours, breaking the emulsion with aluminum sulfate, filtering, washing and drying to obtain a composite polymer.

[0072] Preparation Example 3

[0073] A composite polymer, which differs from Preparation Example 1 in that it is prepared by the following steps: adding distilled water and sodium lauryl sulfate to a container and heating and stirring at a heating temperature of 70°C, adding N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer in a weight ratio of 12:20:1, mixing evenly, adding an initiator, heating to 95°C and reacting for 6 hours, breaking the emulsion with aluminum sulfate, filtering, washing and drying to obtain a composite polymer.

[0074] Preparation Example 4

[0075] A composite polymer, which is different from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 11:18:1.

[0076] Preparation Example 5

[0077] A composite polymer, which is different from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 13:22:1.

[0078] Preparation Example 6

[0079] A composite polymer, which is different from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 10:17:1.

[0080] Preparation Example 7

[0081] A composite polymer, which is different from Preparation Example 1 in that the weight ratio of N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer is 14:23:1.

[0082] Preparation Example 8

[0083] A zeolite-multi-walled carbon nanotube composite is prepared by the following steps:

[0084] S1, taking a multi-walled carbon nanotube raw material and immersing it in a 70% nitric acid solution for 7.5 minutes, taking it out and washing it with water and drying it to obtain surface-modified multi-walled carbon nanotubes;

[0085] S2. Zeolite and surface-modified multi-walled carbon nanotubes are mixed and dispersed in an ethanol solution 5 times the weight of the solution at a weight ratio of 18:1, and ultrasonically shaken to mix evenly. The zeolite-multi-walled carbon nanotube composite is obtained after drying.

[0086] Note: In step S2, the concentration of the ethanol solution is 60%; the ultrasonic oscillation power is 600 W, and the time is 10 min; the particle size of the zeolite is 5 mm, and the diameter of the multi-walled carbon nanotubes is 20 nm and the length is 1.5 μm.

[0087] Preparation Example 9

[0088] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that step S1 is specifically set as: taking the multi-walled carbon nanotube raw material and immersing it in a 65% nitric acid solution for 10 minutes, taking it out and washing it with water and drying it to obtain surface-modified multi-walled carbon nanotubes.

[0089] Preparation Example 10

[0090] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that step S1 is specifically set as: taking the multi-walled carbon nanotube raw material and immersing it in a 75% nitric acid solution for 5 minutes, taking it out and washing it with water and drying it to obtain surface-modified multi-walled carbon nanotubes.

[0091] Preparation Example 11

[0092] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the particle size of the zeolite is 4 mm, and the diameter of the multi-walled carbon nanotube is 10 nm and the length is 1 μm.

[0093] Preparation Example 12

[0094] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the particle size of the zeolite is 6 mm, and the diameter of the multi-walled carbon nanotube is 30 nm and the length is 2 μm.

[0095] Preparation Example 13

[0096] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 14:1.

[0097] Preparation Example 14

[0098] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 26:1.

[0099] Preparation Example 15

[0100] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 20:1.

[0101] Preparation Example 16

[0102] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 13:1.

[0103] Preparation Example 17

[0104] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the weight ratio of zeolite to surface-modified multi-walled carbon nanotubes is 27:1.

[0105] Preparation Example 18

[0106] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the particle size of the zeolite is 3.5 mm, and the diameter of the multi-walled carbon nanotube is 8 nm and the length is 0.8 μm.

[0107] Preparation Example 19

[0108] A zeolite-multi-walled carbon nanotube composite material is different from Preparation Example 8 in that the particle size of the zeolite is 6.5 mm, and the diameter of the multi-walled carbon nanotube is 32 nm and the length is 2.2 μm.

[0109] Example

[0110] Example 1

[0111] A shielding PVC mesh material comprises a mounting layer, a PVC coating, a polyester fiber mesh layer, a PVC coating, an adhesive layer, and an electromagnetic shielding layer, the components of the PVC coating and their corresponding weights being shown in Table 1. The material is prepared by the following steps:

[0112] (1) preparing raw materials including a mounting layer, a polyester fiber mesh layer, a PVC coating, an adhesive layer, and an electromagnetic shielding layer according to a ratio, wherein the PVC coating comprises the following components: PVC resin, a plasticizer, a stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass microbeads, a flame retardant, an anti-UV agent, an antioxidant, an anti-mildew agent, and a composite polymer;

[0113] (2) PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass beads, flame retardant, anti-UV agent, antioxidant, mildew inhibitor and composite polymer are mixed and then ground to obtain PVC paste;

[0114] (3) After preheating the polyester fiber mesh layer in step (1), PVC paste is applied on both sides, and after coagulation and plasticization, the plasticization temperature is 145°C and the time is 15 minutes. A layer of PVC paste is then applied on the front and back sides respectively, and after coagulation and plasticization, the plasticization temperature is 160°C and the time is 10 minutes to obtain a PVC coating;

[0115] (4) In step (3), glue is applied to the front side of the PVC coating, and then a layer of electromagnetic shielding cloth is compounded to form an adhesive layer and an electromagnetic shielding layer; the back side is subjected to mounting treatment to form a mounting layer; and finally, a shielding PVC mesh material is obtained.

[0116] Note: In the above operation, the bonding layer is acrylic glue, the mounting layer is PVF film; the polyester fiber mesh layer is 0.2 mm, the inner PVC coating is 0.3 mm, the outer PVC coating is 0.3 mm, the mounting layer is 0.1 mm, and the bonding layer is 0.1 mm; the composite polymer used is obtained from Preparation Example 1.

[0117] Example 2-3

[0118] A shielding PVC mesh material is different from Example 1 in that the raw materials of the components of the PVC coating and their corresponding weights are shown in Table 1.

[0119] Table 1 Raw materials of various components of PVC coating in Examples 1-3 and their weight parts (kg / part)

[0120] Example 4

[0121] A shielding PVC mesh material, which is different from Example 1 in that the composite polymer used is obtained from Preparation Example 2.

[0122] Example 5

[0123] A shielding PVC mesh material, which is different from Example 1 in that the composite polymer used is obtained from Preparation Example 3.

[0124] Example 6

[0125] A shielding PVC mesh material, which is different from Example 1 in that the composite polymer used is obtained from Preparation Example 4.

[0126] Example 7

[0127] A shielding PVC mesh material, which is different from Example 1 in that the composite polymer used is obtained from Preparation Example 5.

[0128] Example 8

[0129] A shielding PVC mesh material, which is different from Example 1 in that the composite polymer used is obtained from Preparation Example 6.

[0130] Example 9

[0131] A shielding PVC mesh material, which is different from Example 1 in that the composite polymer used is obtained from Preparation Example 7.

[0132] Example 10

[0133] A shielding PVC mesh material is different from Example 1 in that 6.5 parts by weight of a zeolite-multi-walled carbon nanotube composite are further added to the components of the PVC coating; the zeolite-multi-walled carbon nanotube composite is obtained in Preparation Example 8.

[0134] Example 11

[0135] A shielding PVC sandwich material is different from Example 10 in that the weight portion of the zeolite-multi-walled carbon nanotube composite material added is 5 parts.

[0136] Example 12

[0137] A shielding PVC sandwich material is different from Example 10 in that the weight portion of the zeolite-multi-walled carbon nanotube composite material added is 8 parts.

[0138] Example 13

[0139] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 9.

[0140] Example 14

[0141] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 10.

[0142] Example 15

[0143] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 11.

[0144] Example 16

[0145] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 12.

[0146] Example 17

[0147] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 13.

[0148] Example 18

[0149] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 14.

[0150] Example 19

[0151] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 15.

[0152] Example 20

[0153] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 16.

[0154] Example 21

[0155] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 17.

[0156] Example 22

[0157] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 18.

[0158] Example 23

[0159] A shielding PVC mesh material, which is different from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is obtained in Preparation Example 19.

[0160] Example 24

[0161] A shielding PVC sandwich material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is replaced by zeolite.

[0162] Example 25

[0163] A shielding PVC sandwich material, which differs from Example 10 in that the zeolite-multi-walled carbon nanotube composite material is replaced by multi-walled carbon nanotubes.

[0164] Example 26

[0165] A shielding PVC mesh material is different from Example 10 in that 2 parts by weight of basalt fiber are further added to the components of the PVC coating, and the basalt fiber has a diameter of 1 mm and a length of 5 cm.

[0166] Example 27

[0167] A shielding PVC mesh material, which is different from Example 26 in that the weight portion of basalt fiber added is 1 part.

[0168] Example 28

[0169] A shielding PVC mesh material, which is different from Example 26 in that the weight of the added basalt fiber is 3 parts.

[0170] Example 29

[0171] A shielding PVC mesh material, which is different from Example 26 in that the diameter of the basalt fiber is 0.5 mm and the length is 4 cm.

[0172] Example 30

[0173] A shielding PVC mesh material, which differs from Example 26 in that the diameter of the basalt fiber is 1.5 mm and the length is 6 cm.

[0174] Example 31

[0175] A shielding PVC mesh material, which differs from Example 26 in that the diameter of the basalt fiber is 0.4 mm and the length is 3.5 cm.

[0176] Example 32

[0177] A shielding PVC mesh material, which differs from Example 26 in that the diameter of the basalt fiber is 1.6 mm and the length is 6.5 cm.

[0178] Example 33

[0179] A shielding PVC mesh material, which differs from Example 26 in that the components of the PVC coating do not contain zeolite-multi-walled carbon nanotube composite.

[0180] Comparative Example

[0181] Comparative Example 1

[0182] A shielding PVC mesh material is different from Example 1 in that the components of the PVC coating do not contain a composite polymer.

[0183] Comparative Example 2

[0184] A shielding PVC mesh material, which is different from Example 10 in that the components of the PVC coating do not contain a composite polymer.

[0185] Performance testing

[0186] Test samples: The shielded PVC mesh material obtained in Example 1-33 was used as test sample 1-33, and the shielded PVC mesh material obtained in Comparative Example 1-2 was used as control sample 1-2.

[0187] Test method: According to the standard SJ20524-1995 "Measurement method of shielding effectiveness of materials", the electromagnetic shielding effectiveness of test samples 1-33 and control sample 1-2 was measured, and recorded as the initial electromagnetic shielding effectiveness; then the test samples 1-33 and control sample 1-2 were placed in a simulated high temperature environment on the plateau, the temperature was 48 ° C, and the relative humidity of the air was 30%. After being placed for 7 days, the electromagnetic shielding effectiveness of the test samples 1-33 and the control sample 1-2 was measured by the same method, and recorded as the electromagnetic shielding effectiveness after the test; finally, the electromagnetic shielding effectiveness loss rate of each sample was calculated, and the electromagnetic shielding effectiveness loss rate (%) = (initial electromagnetic shielding effectiveness - electromagnetic shielding effectiveness after the test) / initial electromagnetic shielding effectiveness, which is recorded in the following Table 2.

[0188] Table 2 Test results of test samples 1-33 and control samples 1-2

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

[0190] Combining Example 1 with Examples 6-9 and 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 can exert a stable effect during application, making the shielding PVC mesh material have a low electromagnetic shielding effectiveness loss rate. Among them, when the weight ratio of N-cyclohexylmaleimide, methacrylic acid, and hexafluoropropylene trimer is 12:20:1, the shielding PVC mesh material has excellent stability in a long-term high-temperature environment. When the weight ratio of the above raw materials exceeds the above range, the application effect of the composite polymer will be greatly reduced, and the electromagnetic shielding effectiveness loss rate will be significantly increased. Therefore, it can be seen that the weight ratio of the three raw materials is particularly important for obtaining a composite polymer with stable and excellent functions.

[0191] Combining Example 1 with Examples 10-14 and 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 in long-term high-temperature conditions, further reducing the electromagnetic shielding effectiveness loss rate measured by the shielded PVC mesh material. 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, it is found that the improvement effect brought by the zeolite-multi-walled carbon nanotube composite is far less excellent than that of Example 10, indicating that the composite polymer and the zeolite-multi-walled carbon nanotube composite have a synergistic effect, and the mutual cooperation between the two can greatly improve the stability of the shielded PVC mesh material in a long-term high-temperature environment.

[0192] Combining Example 10 with Examples 17-21 and Table 2, it can be seen that in the preparation of the zeolite-multi-walled carbon nanotube composite, the zeolite and the surface-modified multi-walled carbon nanotubes are combined in a weight ratio of (14-26):1 to obtain a zeolite-multi-walled carbon nanotube composite with excellent quality and stability. 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, thereby making the electromagnetic shielding layer less susceptible to significant damage. The measured electromagnetic shielding effectiveness loss rate of the shielded PVC mesh material is relatively low. However, when the combination of the two exceeds the above range, the application effect of the zeolite-multi-walled carbon nanotube composite in the PVC coating is greatly reduced.

[0193] From Example 10, Examples 15-16, Examples 22-23 and Table 2, it can be seen that the particle size of the zeolite is 4-6 mm, the diameter of the multi-walled carbon nanotubes is 10-30 nm, and the length is 1-2 μm, which can ensure that the zeolite-multi-walled carbon nanotube composite material exerts an excellent and stable effect when used in the PVC coating. Exceeding the above specifications will lead 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 between the raw materials leads to poor performance of the morphology and structure of the zeolite-multi-walled carbon nanotube composite in application integration in the PVC coating.

[0194] From Example 10 and Examples 24-25 and Table 2, it can be seen that if zeolite or multi-walled carbon nanotubes are added alone to the PVC coating, the stability of the PVC coating in a long-term high-temperature environment is limited, and the improvement effect is far inferior to the excellent zeolite-multi-walled carbon nanotube composite. Therefore, it can be seen that the zeolite-multi-walled carbon nanotube composite prepared from zeolite and multi-walled carbon nanotubes has an outstanding improvement effect on the stability of the shielding PVC mesh material in a long-term high-temperature environment.

[0195] Combining Example 10 with Examples 26-28 and Table 2, it can be seen that the addition of basalt fiber can further improve the high-temperature resistance of the PVC coating, thereby making the electromagnetic shielding layer less susceptible to damage. The measured electromagnetic shielding efficiency loss rate of the shielded PVC mesh material is also further reduced. 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 enables it to exert an excellent and stable lifting effect during its application. However, when the above specifications are exceeded, it is found that the lifting effect is not ideal. Combining Example 33 with Table 2, it can be seen that when basalt fiber is used in a PVC coating that does not contain a zeolite-multi-walled carbon nanotube composite, it is found that the lifting effect brought by the basalt fiber is far less excellent than that of Example 26, indicating that there is a synergistic effect between the basalt fiber and the zeolite-multi-walled carbon nanotube composite. The mutual cooperation between the two 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 the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A shielding PVC mesh material, characterized in that: The invention comprises a mounting layer, a PVC coating, a polyester fiber mesh layer, a PVC coating, an adhesive layer and an electromagnetic shielding layer which are arranged in sequence, wherein the PVC coating comprises the following components in parts by weight: PVC resin 90-100 parts; Plasticizer 60-75 parts; 3-6 parts of stabilizer; 2-4 parts soybean oil; 10-18 parts of titanium dioxide; Calcium carbonate 25-45 parts; Glass beads 15-40 parts; Flame retardant 6-15 parts; 1-3 parts of anti-UV agent; 1-2 parts of antioxidant; 2.5-4 parts of mildew inhibitor; 5-10 parts of composite polymer; The composite polymer is prepared by the following steps: Add distilled water and sodium dodecyl sulfate into a container and heat with stirring at a heating temperature of 60-70°C, add N-cyclohexylmaleimide, methacrylic acid and hexafluoropropylene trimer in a weight ratio of (11-13):(18-22):1, mix well and then add initiator, heat to 85-95°C and react for 4-6 hours, demulsify with aluminum sulfate and filter, wash and dry to obtain a composite polymer.

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: The components of the PVC coating are further added with 5-8 parts by weight of a zeolite-multi-walled carbon nanotube composite, and the zeolite-multi-walled carbon nanotube composite is prepared by the following steps: S1, immersing the multi-walled carbon nanotube raw material in a nitric acid solution with a concentration of 65-75% for 5-10 minutes, taking it out, washing it with water and drying it, to obtain the surface-modified multi-walled carbon nanotube; S2. Zeolite and surface-modified multi-walled carbon nanotubes are dispersed in an ethanol solution at a weight ratio of (14-26):1, mixed evenly by ultrasonic vibration, and dried to obtain a zeolite-multi-walled carbon nanotube composite.

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

1.

5. The shielding PVC mesh material according to claim 3, characterized in that: The particle size of the zeolite is 4-6 mm, the diameter of the multi-walled carbon nanotube is 10-30 nm, and the length is 1-2 μm.

6. The shielding PVC mesh material according to claim 3, characterized in that: The components of the PVC coating are also added with 1-3 parts by weight of basalt fiber.

7. The shielding PVC mesh material according to claim 6, characterized in that: The basalt fiber has a diameter of 0.5-1.5 mm and a length of 4-6 cm.

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

9. The method for preparing the shielding PVC mesh material according to claim 1, characterized in that: The following steps are involved: (1) Prepare the following materials according to the ratio: mounting layer, polyester fiber mesh layer, PVC coating layer, adhesive layer and The raw materials of the electromagnetic shielding layer, wherein the PVC coating comprises 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; (2) PVC resin, plasticizer, stabilizer, soybean oil, titanium dioxide, calcium carbonate, glass beads, flame retardant, UV inhibitor, antioxidant, mildew inhibitor and composite polymer are uniformly mixed and then ground to obtain PVC paste; (3) After preheating the polyester fiber mesh layer in step (1), PVC paste is coated on both sides, and after coagulation and plasticization, a layer of PVC paste is coated on the front and back sides respectively, and after coagulation and plasticization, a PVC coating is obtained; (4) In step (3), glue is applied to the front side of the PVC coating, and then a layer of electromagnetic shielding cloth is compounded to form an adhesive layer and an electromagnetic shielding layer; the back side is subjected to mounting treatment to form a mounting layer; and finally a shielding PVC mesh material is obtained.

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