A high-resistance and high-toughness 60-core parallel wire heating wire and its preparation method

Abstract

The present invention relates to a high-resistance and high-toughness 60-core paralleled heating wire and a preparation method thereof, belonging to the field of heating wires. The heating wire comprises glass fiber, an insulating alloy wire twisted on the glass fiber, and a silicone sleeve encapsulated on the outside of the insulating alloy wire, wherein the insulating alloy wire comprises an alloy heating wire core and a modified PVC protective layer on its surface, the modified PVC protective layer comprising: 100 parts of PVC resin, 4.5-5.5 parts of plasticizer, 3-6 parts of mica powder, 1-2 parts of aluminum nitride powder, 0.5-1 parts of asbestos powder, 2-3 parts of silane coupling agent, 0.2-0.3 parts of accelerator, and 6-8 parts of xylene; the molecular end of the plasticizer is synthesized with a branched formate ester, which can be embedded with PVC to play a stabilizing and toughening role; the middle part of the molecule contains a network of nitrogen-containing structures, which has a chelating effect with the mica powder and aluminum nitride powder, fixes the powder in the matrix, and plays a stabilizing insulation and compressive resistance role.

Description

Technical Field

[0001] The present invention belongs to the technical field of heating wires, and in particular relates to a high-resistance and high-toughness 60-core paralleled wire heating wire and a preparation method thereof. Background Art

[0002] Heating wires, also known as heating wires or electric heating wires, generate heat by applying electricity. They are primarily used for heating heating equipment, defrosting refrigeration equipment, applying heat in the medical industry, maintaining heat in industrial production, and removing snow from transportation. Heating wires look similar to ordinary electrical wires, consisting primarily of fiberglass, a heating wire, and a protective sheath.

[0003] In order to ensure the safety of the heating wire and the insulation of the multi-core heating wire, the surface of the heating wire generally needs to be protected, and PVC rubber sleeves are usually used for packaging. However, the toughness of pure PVC material is poor, and the protective layer is easily cracked during the multi-core twisting process, resulting in protection failure; the existing PVC protective materials used for heating wires need to be toughened. The most economical and suitable method for industrial production is to add plasticizers. Common plasticizers mainly include two categories. One is to add ultrafine inorganic particles, such as calcium carbonate, silicon dioxide, etc., which have a certain toughening effect, but the addition amount is limited. Excessive addition will cause PVC hardening and aggravate twisting cracks. The second is to add organic toughening agents, such as dioctyl phthalate, etc. The toughening effect is improved compared to inorganic toughening agents. However, this type of toughening agent has poor migration resistance and the toughening effect is not stable and ideal. Summary of the Invention

[0004] In order to solve the technical problems mentioned in the background technology, the purpose of the present invention is to provide a high-resistance and high-toughness 60-core paralleled heating wire and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A high-resistance and high-toughness 60-core paralleled wire heating wire, including glass fiber, insulating alloy wire and silicone sheath, the insulating alloy wire is twisted on the surface of the glass fiber, and the silicone sheath is encapsulated on the outside of the insulating alloy wire; wherein, the insulating alloy wire includes an alloy heating wire core and a modified PVC protective layer on its surface.

[0007] The modified PVC protective layer comprises the following raw materials:

[0008] 100 parts of PVC resin, 4.5-5.5 parts of plasticizer, 3-6 parts of mica powder, 1-2 parts of aluminum nitride powder, 0.5-1 part of asbestos powder, 2-3 parts of silane coupling agent, 0.2-0.3 parts of accelerator and 6-8 parts of xylene;

[0009] The plasticizer is prepared by the following method:

[0010] Step A1: Preheat diethanolamine, anhydrous ethanol, and sodium ethoxide to dissolve in a mixed solution, then maintain the temperature at 65-72°C with a stirring rate of 240-360 rpm, and slowly dropwise add triallylamine. The total dropwise reaction time is controlled to be 3-4 hours, and then the anhydrous ethanol solvent is removed by rotary evaporation to obtain an intermediate.

[0011] Furthermore, the dosage ratio of triallylamine, diethanolamine, sodium ethoxide and anhydrous ethanol is 0.1 mol: 0.32-0.33 mol: 0.9-1.4 g: 55-65 mL. Triallylamine reacts with the secondary amine group in diethanolamine under the catalysis of sodium ethoxide. The specific reaction process is as follows:

[0012]

[0013] Step A2: The intermediate and DMF were mixed, and then formic acid and p-toluenesulfonic acid were added. The stirring rate was set at 180-300 rpm, and the temperature was raised to 60-80°C and stirred for 2-2.6 hours. The temperature was then further raised to 105-110°C and refluxed for 40-60 minutes. After the reaction was completed, deionized water was added and the solvent DMF and excess formic acid were removed by rotary evaporation under reduced pressure several times to obtain a plasticizer.

[0014] Furthermore, the ratio of the intermediate, formic acid, p-toluenesulfonic acid, and DMF is 0.1 mol: 0.68-0.75 mol: 0.6-0.7 g: 110-130 mL. Under the catalysis of p-toluenesulfonic acid, formic acid esterifies with the branched hydroxyl groups on the intermediate molecule. The specific reaction process is as follows:

[0015]

[0016] A method for preparing a high-resistance and high-toughness 60-core paralleled wire heating wire comprises the following steps:

[0017] Step S1: mixing mica powder, aluminum nitride powder and asbestos powder, mixing a silane coupling agent and xylene, and then mixing the two evenly to obtain a premix;

[0018] Step S2: heating the PVC resin, plasticizer, and premix to 80-90°C and mixing for 5-8 minutes, then adding the accelerator, and continuing to heat to 160-175°C and high-speed shear mixing for 12-15 minutes to obtain the protective adhesive;

[0019] Step S3: Extruding a protective adhesive and coating the surface of the alloy heating wire core, spraying and rapidly cooling the core to below 100°C, then heat-keeping the core at 80-85°C for 15-20 minutes for homogenization, and solidifying the protective adhesive to form a modified PVC protective layer, thereby obtaining an insulated alloy wire;

[0020] Step S4: Twisting several groups of insulated alloy wires on the surface of the glass fiber, and then encapsulating the outer side with a silicone sleeve to obtain a heating wire.

[0021] Beneficial effects of the present invention:

[0022] The present invention prepares a plasticizer for improving the toughness of a PVC matrix, and applies the plasticizer to protect alloy heating wire cores to prevent breakage during the twisting process. The plasticizer uses triallylamine as a raw material, is modified with diethanolamine, and introduces branched hydroxyl groups through the addition of double bonds and secondary amines. The branched hydroxyl groups are then esterified with formic acid to form formate end caps. The formate has good compatibility with the PVC matrix and can be uniformly dispersed in the matrix. Compared with existing toughening agents, the formate has better dispersibility and is not easy to migrate, thus playing a stable toughening role for the PVC matrix. In addition, the molecular structure of the plasticizer contains a network of nitrogen-containing structures in the middle, which has a chelating effect with mica powder and aluminum nitride powder, fixing the powder in the matrix and playing a role in stable insulation and compression resistance. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0024] Example 1

[0025] This embodiment prepares a high-resistance and high-toughness 60-core paralleled heating wire. The specific implementation process is as follows:

[0026] 1) Preparation of plasticizer

[0027] a1. Add diethanolamine, anhydrous ethanol, and sodium ethoxide into a reactor, preheat to 40°C, apply mechanical stirring to dissolve, then maintain a constant temperature at 65°C with a stirring rate of 240 rpm. Slowly add triallylamine dropwise to the reactor over 50 minutes. After the addition, keep the temperature and stirring to react. The total dropwise reaction time is controlled to 4 hours. After the reaction is completed, remove low-boiling substances including the solvent anhydrous ethanol by rotary evaporation to prepare an intermediate, wherein the amount ratio of triallylamine, diethanolamine, sodium ethoxide, and anhydrous ethanol is 0.1 mol:0.32 mol:0.9 g:55 mL.

[0028] a2. The intermediate and DMF were added to the reaction mixture, mechanically stirred and mixed for 10 minutes, and then formic acid and p-toluenesulfonic acid were added. The stirring rate was set to 180 rpm, and the temperature was raised to 60°C and stirred for 2.6 hours. The temperature was then continued to rise to 105°C and refluxed for 60 minutes. After the reaction was completed, deionized water (1.2 times the mass of the reaction solution) was added in equal amounts three times and vacuum rotary evaporation was performed to remove low-boiling substances including the solvent DMF and excess formic acid to obtain a plasticizer. The amount ratio of the intermediate, formic acid, p-toluenesulfonic acid and DMF was 0.1 mol: 0.68 mol: 0.6 g: 110 mL.

[0029] 2) Preparation of 60-core parallel heating wire

[0030] s1. Ingredients:

[0031] 100 parts of PVC resin, a commercially available resin with a viscosity of 80, and the following examples use the same raw materials;

[0032] 5.5 parts of plasticizer;

[0033] 3 parts mica powder;

[0034] 2 parts of aluminum nitride powder;

[0035] 0.5 parts of asbestos powder; the fineness of the above powder is 200 mesh, and the following examples use the same raw materials;

[0036] 2 parts of silane coupling agent, selected from silane coupling agent KH570, the following examples use the same raw materials;

[0037] 0.2 parts of accelerator, selected from dicumyl peroxide, the following examples use the same raw materials;

[0038] 6 parts of xylene.

[0039] s2. Premixing: Add mica powder, aluminum nitride powder and asbestos powder to a pneumatic powder mixer and mix them evenly. Then, add silane coupling agent and xylene and stir them. Then, stir the mixed liquid and mixed powder into a uniform paste to obtain a premix.

[0040] s3. Rubber mixing: Take PVC resin, plasticizer and premix, heat to 80℃ and mix for 8 minutes, then add accelerator, continue to heat to 160℃ and high-speed shear mixing for 15 minutes to obtain protective rubber;

[0041] s4. Glue coating: Extrude and coat the protective glue on the surface of the alloy heating wire core, spray and quickly cool to below 100°C, then keep at 80°C for 20 minutes for homogenization, and the protective glue solidifies to form a modified PVC protective layer to obtain an insulated alloy wire;

[0042] s5. Parallel wire assembly: 60 groups of insulated alloy wires are twisted together on the surface of the glass fiber, and then a silicone sleeve is encapsulated on the outside to obtain a 60-core parallel wire heating wire.

[0043] Example 2

[0044] This embodiment prepares a high-resistance and high-toughness 60-core paralleled heating wire. The specific implementation process is as follows:

[0045] 1) Preparation of plasticizer

[0046] a1. Add diethanolamine, anhydrous ethanol, and sodium ethoxide into a reactor, preheat to 50°C, apply mechanical stirring to dissolve, then maintain a constant temperature at 72°C with a stirring rate of 360 rpm. Slowly add triallylamine dropwise to the reactor over 30 minutes. After the addition, keep the temperature and stirring to react. The total dropwise reaction time is controlled to 3 hours. After the reaction is completed, remove low-boiling substances including the solvent anhydrous ethanol by rotary evaporation to prepare an intermediate, wherein the amount ratio of triallylamine, diethanolamine, sodium ethoxide, and anhydrous ethanol is 0.1 mol:0.33 mol:1.4 g:65 mL.

[0047] a2. The intermediate and DMF were added to the reaction mixture, mechanically stirred and mixed for 10 minutes, and then formic acid and p-toluenesulfonic acid were added. The stirring rate was set to 300 rpm, and the temperature was raised to 80°C and stirred for 2 hours. The temperature was then continued to rise to 110°C and refluxed for 40 minutes. After the reaction was completed, deionized water (1.8 times the mass of the reaction solution) was added in equal amounts three times and vacuum rotary evaporation was performed to remove low-boiling substances including the solvent DMF and excess formic acid to obtain a plasticizer. The amount ratio of the intermediate, formic acid, p-toluenesulfonic acid and DMF was 0.1 mol: 0.75 mol: 0.7 g: 130 mL.

[0048] 2) Preparation of 60-core parallel heating wire

[0049] s1. Ingredients:

[0050] 100 parts of PVC resin, a commercially available resin with a viscosity of 80, and the following examples use the same raw materials;

[0051] 5 parts of plasticizer;

[0052] 6 parts of mica powder;

[0053] 1.5 parts of aluminum nitride powder;

[0054] 0.6 parts of asbestos powder;

[0055] 2.3 parts of silane coupling agent;

[0056] 0.2 parts of accelerator;

[0057] 7 parts of xylene.

[0058] s2. Premixing: Add mica powder, aluminum nitride powder and asbestos powder to a pneumatic powder mixer and mix them evenly. Then, add silane coupling agent and xylene and stir them. Then, stir the mixed liquid and mixed powder into a uniform paste to obtain a premix.

[0059] s3. Rubber mixing: Take PVC resin, plasticizer and premix, heat to 90℃ and mix for 5 minutes, then add accelerator, continue to heat to 175℃ and high-speed shear mixing for 12 minutes to obtain protective rubber;

[0060] s4. Glue coating: Extrude and coat the protective glue on the surface of the alloy heating wire core, spray and quickly cool to below 100°C, then keep at 85°C for 15 minutes for homogenization, and the protective glue solidifies to form a modified PVC protective layer to obtain an insulated alloy wire;

[0061] s5. Parallel wire assembly: 60 groups of insulated alloy wires are twisted together on the surface of the glass fiber, and then a silicone sleeve is encapsulated on the outside to obtain a 60-core parallel wire heating wire.

[0062] Example 3

[0063] This embodiment prepares a high-resistance and high-toughness 60-core paralleled heating wire. The specific implementation process is as follows:

[0064] 1) Preparation of plasticizer

[0065] a1. Add diethanolamine, anhydrous ethanol, and sodium ethoxide into a reactor, preheat to 50°C, apply mechanical stirring to dissolve, then maintain a constant temperature at 68°C with a stirring rate of 300 rpm. Slowly add triallylamine dropwise to the reactor over 40 minutes. After the addition, keep the temperature and stirring to react. The total dropwise reaction time is controlled to 3.6 hours. After the reaction is completed, remove low-boiling substances including the solvent anhydrous ethanol by rotary evaporation to prepare an intermediate, wherein the amount ratio of triallylamine, diethanolamine, sodium ethoxide, and anhydrous ethanol is 0.1 mol:0.33 mol:1.2 g:60 mL.

[0066] a2. The intermediate and DMF were added to the reaction mixture, mechanically stirred and mixed for 10 minutes, and then formic acid and p-toluenesulfonic acid were added. The stirring rate was set to 240 rpm, and the temperature was raised to 72°C and stirred for 2.2 hours. The temperature was then continued to rise to 110°C and refluxed for 55 minutes. After the reaction was completed, deionized water (1.5 times the mass of the reaction solution) was added in equal amounts three times and vacuum rotary evaporation was performed to remove low-boiling substances including the solvent DMF and excess formic acid to obtain a plasticizer. The amount ratio of the intermediate, formic acid, p-toluenesulfonic acid and DMF was 0.1 mol: 0.72 mol: 0.6 g: 120 mL.

[0067] 2) Preparation of 60-core parallel heating wire

[0068] s1. Ingredients:

[0069] 100 parts of PVC resin, a commercially available resin with a viscosity of 80, and the following examples use the same raw materials;

[0070] 5.2 parts of plasticizer;

[0071] 4 parts mica powder;

[0072] 1.2 parts of aluminum nitride powder;

[0073] 0.8 parts of asbestos powder;

[0074] 2.5 parts of silane coupling agent;

[0075] 0.3 parts of accelerator;

[0076] 7.5 parts of xylene.

[0077] s2. Premixing: Add mica powder, aluminum nitride powder and asbestos powder to a pneumatic powder mixer and mix them evenly. Then, add silane coupling agent and xylene and stir them. Then, stir the mixed liquid and mixed powder into a uniform paste to obtain a premix.

[0078] s3. Rubber mixing: Take PVC resin, plasticizer and premix, heat it to 88℃ and mix for 7 minutes, then add accelerator, continue to heat it to 170℃ and mix it at high speed for 14 minutes to obtain protective rubber;

[0079] s4. Glue coating: Extrude and coat the protective glue on the surface of the alloy heating wire core, spray and quickly cool to below 100°C, then keep at 85°C for 18 minutes for homogenization, and the protective glue solidifies to form a modified PVC protective layer to obtain an insulated alloy wire;

[0080] s5. Parallel wire assembly: 60 groups of insulated alloy wires are twisted together on the surface of the glass fiber, and then a silicone sleeve is encapsulated on the outside to obtain a 60-core parallel wire heating wire.

[0081] Example 4

[0082] This embodiment prepares a high-resistance and high-toughness 60-core paralleled heating wire. The specific implementation process is as follows:

[0083] 1) Preparation of plasticizer

[0084] a1. Add diethanolamine, anhydrous ethanol, and sodium ethoxide into a reactor, preheat to 50°C, apply mechanical stirring to dissolve, then maintain a constant temperature at 70°C with a stirring rate of 360 rpm. Slowly add triallylamine dropwise to the reactor over 40 minutes. After the addition, keep the temperature and stirring to react. The total dropwise reaction time is controlled to 3.5 hours. After the reaction is completed, remove low-boiling substances including the solvent anhydrous ethanol by rotary evaporation to prepare an intermediate, wherein the amount ratio of triallylamine, diethanolamine, sodium ethoxide, and anhydrous ethanol is 0.1 mol:0.33 mol:1.1 g:65 mL.

[0085] a2. The intermediate and DMF were added to the reaction mixture, mechanically stirred and mixed for 10 minutes, and then formic acid and p-toluenesulfonic acid were added. The stirring rate was set to 300 rpm, and the temperature was raised to 75°C and stirred for 2.4 hours. The temperature was then continued to rise to 110°C and refluxed for 50 minutes. After the reaction was completed, deionized water (1.5 times the mass of the reaction solution) was added in equal amounts three times and vacuum rotary evaporation was performed to remove low-boiling substances including the solvent DMF and excess formic acid to obtain a plasticizer. The amount ratio of the intermediate, formic acid, p-toluenesulfonic acid and DMF was 0.1 mol: 0.72 mol: 0.65 g: 120 mL.

[0086] 2) Preparation of 60-core parallel heating wire

[0087] s1. Ingredients:

[0088] 100 parts of PVC resin, a commercially available resin with a viscosity of 80, and the following examples use the same raw materials;

[0089] 4.5 parts of plasticizer;

[0090] 4 parts mica powder;

[0091] 1 part aluminum nitride powder;

[0092] 1 part asbestos powder;

[0093] 2 parts of silane coupling agent;

[0094] 0.3 parts of accelerator;

[0095] 8 parts of xylene.

[0096] s2. Premixing: Add mica powder, aluminum nitride powder and asbestos powder to a pneumatic powder mixer and mix them evenly. Then, add silane coupling agent and xylene and stir them. Then, stir the mixed liquid and mixed powder into a uniform paste to obtain a premix.

[0097] s3. Rubber mixing: Take PVC resin, plasticizer and premix, heat it to 85℃ and mix for 7 minutes, then add accelerator, continue to heat it to 170℃ and mix at high speed for 15 minutes to obtain protective rubber;

[0098] s4. Glue coating: Extrude and coat the protective glue on the surface of the alloy heating wire core, spray and quickly cool to below 100°C, then keep at 85°C for 18 minutes for homogenization, and the protective glue solidifies to form a modified PVC protective layer to obtain an insulated alloy wire;

[0099] s5. Parallel wire assembly: 60 groups of insulated alloy wires are twisted together on the surface of the glass fiber, and then a silicone sleeve is encapsulated on the outside to obtain a 60-core parallel wire heating wire.

[0100] Comparative Example 1

[0101] This comparative example has the same implementation process as Example 3, except that 5 parts of the plasticizer prepared in Example 3 are replaced by an existing superior composite plasticizer consisting of 3.5 parts of dioctyl phthalate and 5.8 parts of ultrafine calcium carbonate (fineness of 500 mesh).

[0102] To verify the role of the modified PVC protective layer in the heating wire, the protective adhesives prepared in Examples 1 to 4 and Comparative Example 1 were extruded into a mold coated with a release agent and cured using the method of Example 3. Thin sheet samples were then prepared and tested as follows:

[0103] Refer to GB / T 528-2009 standard for tensile strength test;

[0104] Refer to GB / T 3923.1-2013 standard for elongation at break test;

[0105] Refer to GB / T 1410-2006 standard for volume resistivity test;

[0106] The specific test data is shown in Table 1:

[0107] Table 1

[0108]

[0109] As can be seen from the data in Table 1, the modified PVC protective layer on the surface of the heating wire prepared by the present invention has good tensile strength, an elongation at break of 359.4-381.6%, excellent toughness on the surface, and a volume resistivity of 10 14 Ω·cm, with high resistivity.

[0110] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these 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 any one or more embodiments or examples.

[0111] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A high-resistance and high-toughness 60-core paralleled heating wire, comprising glass fiber, insulating alloy wire and silicone sheath, characterized in that: The insulated alloy wire includes an alloy heating wire core and a modified PVC protective layer on its surface. The modified PVC protective layer includes the following raw materials: 100 parts of PVC resin, 4.5-5.5 parts of plasticizer, 3-6 parts of mica powder, 1-2 parts of aluminum nitride powder, 0.5-1 part of asbestos powder, 2-3 parts of silane coupling agent, 0.2-0.3 parts of accelerator and 6-8 parts of xylene; The plasticizer is prepared by the following method: Step A1: Preheat and dissolve diethanolamine, anhydrous ethanol, and sodium ethoxide, then add triallylamine dropwise at a constant temperature of 65-72°C with stirring. The total reaction time is controlled to be 3-4 hours, and then the anhydrous ethanol solvent is removed by rotary evaporation to obtain an intermediate. Step A2: The intermediate and DMF were mixed, formic acid and p-toluenesulfonic acid were added, the stirring rate was set to 180-300 rpm, the temperature was raised to 60-80°C and stirred for 2-2.6 hours, and then the temperature was continued to be raised to 105-110°C and refluxed for 40-60 minutes. After the reaction was completed, deionized water was added and the solvent DMF and excess formic acid were removed by vacuum rotary evaporation several times to obtain a plasticizer.

2. The high-resistance and high-toughness 60-core paralleled heating wire according to claim 1, characterized in that: The usage ratio of triallylamine, diethanolamine, sodium ethoxide and anhydrous ethanol is 0.1 mol: 0.32-0.33 mol: 0.9-1.4 g: 55-65 mL.

3. The high-resistance and high-toughness 60-core paralleled heating wire according to claim 2, characterized in that: The usage ratio of the intermediate, formic acid, p-toluenesulfonic acid and DMF is 0.1 mol: 0.68-0.75 mol: 0.6-0.7 g: 110-130 mL.

4. The method for preparing a high-resistance and high-toughness 60-core paralleled heating wire according to claim 3, characterized in that: The steps include: Step S1: mixing mica powder, aluminum nitride powder and asbestos powder, mixing a silane coupling agent and xylene, and then mixing the two evenly to obtain a premix; Step S2: heating the PVC resin, plasticizer, and premix to 80-90°C and mixing for 5-8 minutes, then adding the accelerator, and continuing to heat to 160-175°C and high-speed shear mixing for 12-15 minutes to obtain the protective adhesive; Step S3: Extruding a protective adhesive and coating the surface of the alloy heating wire core, spraying and rapidly cooling the core to below 100°C, then heat-keeping the core at 80-85°C for 15-20 minutes for homogenization, and solidifying the protective adhesive to form a modified PVC protective layer, thereby obtaining an insulated alloy wire; Step S4: Twisting several groups of insulated alloy wires on the surface of the glass fiber, and then encapsulating the outer side with a silicone sleeve to obtain a heating wire.

5. The method for preparing a high-resistance and high-toughness 60-core paralleled heating wire according to claim 4, characterized in that: The fineness of mica powder, aluminum nitride powder and asbestos powder shall not be less than 200 mesh.

6. The method for preparing a high-resistance and high-toughness 60-core paralleled heating wire according to claim 5, characterized in that: The viscosity number of PVC resin is 80.

7. The method for preparing a high-resistance and high-toughness 60-core paralleled heating wire according to claim 6, characterized in that: The silane coupling agent is silane coupling agent KH570.

8. The method for preparing a high-resistance and high-toughness 60-core paralleled heating wire according to claim 7, characterized in that: The accelerator is dicumyl peroxide.

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