Composite modified polyvinyl chloride flexible cable

Abstract

The invention relates to a composite modified polyvinyl chloride flexible cable, and belongs to the technical field of cables. By modifying the polyvinyl chloride resin and adding various additives such as the inorganic filler, the flame retardant wrapped by the shell layer, the plasticizer, the lubricant, the antioxidant and the like, the performance of polyvinyl chloride is improved from the molecular level, so that the composite modified polyvinyl chloride flexible cable has good flame retardance while meeting the flexibility; and the requirements of different application scenes can be met.

Description

Technical Field

[0001] The invention belongs to the technical field of cables and relates to a composite modified polyvinyl chloride soft cable. Background Art

[0002] PVC cables are used in various fields, large and small, to meet the needs of different application scenarios due to their good insulation properties, corrosion resistance, relatively low cost, and easy processing. However, with the diversification of application scenarios and the changes in the environment they may face, the application of PVC cables also has some limitations. For example, in some application scenarios that require frequent bending or movement, PVC cables may be prone to breakage or damage due to insufficient flexibility; in addition, in high temperature environments, PVC cables may soften, deform, or even lose insulation properties. Although PVC cables have certain flame retardancy, they may still burn and release toxic gases and smoke in the event of a fire, causing serious harm to personnel and the environment. Summary of the invention

[0003] The object of the present invention is to provide a composite modified polyvinyl chloride flexible cable. The present invention improves the performance of polyvinyl chloride at the molecular level by modifying polyvinyl chloride resin and adding various additives such as inorganic fillers, shell-wrapped flame retardants, plasticizers, lubricants and antioxidants, so that the composite modified polyvinyl chloride flexible cable has good flame retardancy while meeting the requirements of softness and can meet the needs of different application scenarios.

[0004] The purpose of the present invention can be achieved through the following technical solutions: A composite modified polyvinyl chloride flexible cable. The raw materials of the composite modified polyvinyl chloride flexible cable include, by weight, 50-70 parts of modified polyvinyl chloride resin, 10-30 parts of inorganic filler, 5-15 parts of shell-wrapped flame retardant, 3-5 parts of antioxidant, 2-3 parts of plasticizer and 1.2-3 parts of lubricant.

[0005] Furthermore, the preparation method of the modified polyvinyl chloride resin is: The polyvinyl chloride resin, dibenzoyl peroxide, p-aminobenzenesulfonic acid and methanol are mixed in a mass ratio of 2.3-4.1:0.02-0.04:0.37-0.65:7.5-11.5, stirred at 55-65° C. for 1.5-2.5 hours, rinsed with deionized water and dried to obtain a modified polyvinyl chloride resin.

[0006] Furthermore, the inorganic filler comprises, by weight, 1.2-2 parts of silicon dioxide, 1.3-1.5 parts of calcium carbonate, 0.9-1.6 parts of magnesium hydroxide, and 1.1-1.7 parts of mica; the inorganic filler is obtained by mixing the raw materials and putting them into a ball mill, and ball milling at a speed of 200-500 rpm for 4-6 hours.

[0007] Furthermore, the method for preparing the shell-wrapped flame retardant comprises the following steps: X1. Calcium stearate, zinc stearate and toluene were mixed in a mass ratio of 1:1:6-10, stirred at 280-320 rpm for 30-40 min, and isopropyl tri(dioctyl pyrophosphate) titanate was added dropwise at a rate of 5 ml / min, with a dropwise amount of 5-7 wt% of toluene added, and the temperature was raised to 65-75°C, and stirred at 350-450 rpm for 3-5 h to obtain solution A; X2. The composite flame retardant and solution A are mixed in a mass ratio of 1:1.8-3.2, stirred at a speed of 150-250 rpm for 20-30 min, and spray-dried to obtain a flame retardant wrapped in a shell layer.

[0008] Furthermore, the composite flame retardant in step X2 is obtained by mixing flame retardant A and flame retardant B in a mass ratio of 1:1 and ball milling at a speed of 300-400 rpm for 3-5 hours.

[0009] Furthermore, the flame retardant A is obtained by mixing magnesium hydroxide, butyl orthosilicate and anhydrous ethanol in a mass ratio of 1:0.4-0.6:2-4, stirring at 75-85°C for 3.5-4.5h, and drying; the flame retardant B is obtained by mixing melamine and phosphoric acid in a mass ratio of 1:1.5-1.7, stirring at 110-130°C for 4.5-5.5h, and drying.

[0010] Furthermore, the spray drying parameters of step X2 are: inlet temperature of 140-160°C, outlet temperature of 90-110°C, and spray drying time of 1-2h.

[0011] Furthermore, the plasticizer is prepared by mixing tributyl citrate, montmorillonite and anhydrous ethanol in a mass ratio of 1.2-1.8:0.5-1.5:8-10, stirring at 75-85° C. and 200-600 rpm for 3-4 hours, and drying to obtain the plasticizer.

[0012] Furthermore, the preparation method of the lubricant is: The carbon nanotubes and KH560 are mixed in a mass ratio of 1:0.05-0.07, stirred at 70-90°C for 1-3h, washed and dried to obtain the surface-treated carbon nanotubes; paraffin is heated at 75-85°C for 10-20min, mixed with the surface-treated carbon nanotubes in a mass ratio of 1.2-1.5:0.7-0.8, stirred at a speed of 600-1000rmp for 0.5-1.5h to obtain a lubricant.

[0013] Furthermore, the preparation method of the composite modified polyvinyl chloride flexible cable is: Seven strands of 0.2mm diameter copper wire are twisted to obtain a cross-sectional area of ​​1.5mm 2 The conductor is prepared by mixing modified polyvinyl chloride resin, inorganic filler, flame retardant, antioxidant, plasticizer and lubricant wrapped in a shell, and then melt-extruded at 220-260°C outside the conductor and cooled to form a composite modified polyvinyl chloride soft cable.

[0014] Beneficial effects of the present invention: (1) The modified polyvinyl chloride resin of the present invention introduces p-aminobenzenesulfonic acid, which can change the molecular structure of polyvinyl chloride and increase its polarity and flexibility. The increase in polarity helps to improve the compatibility with other additives, so that each additive can play a better role, thereby improving the overall performance of the cable. The increase in flexibility makes the cable more adaptable to various stresses during use and improves its durability.

[0015] (2) The present invention also introduces a flame retardant wrapped in a shell in the preparation of the cable. The shell formed by calcium stearate, zinc stearate and isopropyl tri(dioctyl pyrophosphate acyloxy) titanate can improve the dispersibility of the flame retardant in polyvinyl chloride, prevent agglomeration, enhance the binding force between the shell and the flame retardant particles, improve the stability of the shell, and increase the compatibility of the flame retardant with polyvinyl chloride. At the same time, a composite flame retardant is added. The butyl orthosilicate in the flame retardant A can be hydrolyzed and condensed under certain conditions to form silicon dioxide, which synergistically acts with magnesium hydroxide. Silicon dioxide can serve as a physical barrier and can also enhance the mechanical strength and thermal stability of the material, making the cable less likely to deform and rupture during the combustion process, thereby better protecting the internal conductor; the phosphoric acid in the flame retardant B can react chemically with melamine at high temperature to accelerate the carbonization process, making the carbon layer denser and more stable, thereby synergistically improving the flame retardant performance of the cable.

[0016] (3) In addition, the tributyl citrate in the present invention can be inserted between the polyvinyl chloride molecular chains as a plasticizer, thereby increasing the distance between the molecular chains, reducing the intermolecular forces, and improving the flexibility and processability. The layered structure of montmorillonite can interact with the tributyl citrate and polyvinyl chloride molecules to improve the stability and durability of the plasticizer. At the same time, the introduction of surface-treated carbon nanotubes and paraffin as lubricants can reduce the friction between the polyvinyl chloride molecular chains, improve the processing performance of the cable, and enhance the flame retardant effect. DETAILED DESCRIPTION

[0017] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0018] Example 1 A composite modified polyvinyl chloride flexible cable. The raw materials of the composite modified polyvinyl chloride flexible cable of this embodiment include 50 parts of modified polyvinyl chloride resin, 10 parts of inorganic filler, 5 parts of shell-wrapped flame retardant, 3 parts of antioxidant, 2 parts of plasticizer and 1.2 parts of lubricant by weight.

[0019] The preparation method of the modified polyvinyl chloride resin of the present embodiment is: Polyvinyl chloride resin, dibenzoyl peroxide, p-aminobenzenesulfonic acid and methanol were mixed in a mass ratio of 2.3:0.02:0.37:7.5, stirred at 55° C. for 1.5 h, rinsed with deionized water and dried to obtain modified polyvinyl chloride resin.

[0020] The inorganic filler of this embodiment includes, by weight, 1.2 parts of silicon dioxide, 1.3 parts of calcium carbonate, 0.9 parts of magnesium hydroxide, and 1.1 parts of mica. The inorganic filler of this embodiment is obtained by mixing various raw materials and putting them into a ball mill, and ball milling them at a speed of 200 rpm for 4 hours.

[0021] The method for preparing the shell-wrapped flame retardant of this embodiment comprises the following steps: X1. Calcium stearate, zinc stearate and toluene were mixed in a mass ratio of 1:1:6, stirred at 280 rpm for 30 min, and isopropyl tri(dioctyl pyrophosphate) titanate was added dropwise at a rate of 5 ml / min, with a drop amount of 5 wt% toluene added, and the temperature was raised to 65°C, and stirred at 350 rpm for 3 h to obtain solution A; X2. The composite flame retardant and solution A were mixed in a mass ratio of 1:1.8, stirred at a speed of 150 rpm for 20 min, and spray-dried to obtain a flame retardant wrapped in a shell.

[0022] In step X2, the composite flame retardant of this embodiment is obtained by mixing flame retardant A and flame retardant B in a mass ratio of 1:1 and ball milling at a speed of 300 rpm for 3 hours.

[0023] The flame retardant A of this embodiment is obtained by mixing magnesium hydroxide, butyl orthosilicate and anhydrous ethanol in a mass ratio of 1:0.4:2, stirring at 75°C for 3.5 hours, and drying; the flame retardant B of this embodiment is obtained by mixing melamine and phosphoric acid in a mass ratio of 1:1.5, stirring at 110°C for 4.5 hours, and drying.

[0024] The spray drying parameters of this embodiment in step X2 are: inlet temperature of 140° C., outlet temperature of 90° C., and spray drying time of 1 h.

[0025] The plasticizer of this embodiment is prepared by mixing tributyl citrate, montmorillonite and anhydrous ethanol in a mass ratio of 1.2:0.5:8, stirring at 75° C. and 200 rpm for 3 hours, and drying to obtain the plasticizer.

[0026] The preparation method of the lubricant of this embodiment is: The carbon nanotubes and KH560 were mixed in a mass ratio of 1:0.05, stirred at 70°C for 1 hour, washed and dried to obtain the surface-treated carbon nanotubes; paraffin was heated at 75°C for 10 minutes, mixed with the surface-treated carbon nanotubes in a mass ratio of 1.2:0.7, stirred at 600 rpm for 0.5 hours to obtain a lubricant.

[0027] The antioxidant in this embodiment is antioxidant 1010.

[0028] The preparation method of the composite modified polyvinyl chloride flexible cable of this embodiment is: Seven strands of 0.2mm diameter copper wire are twisted to obtain a cross-sectional area of ​​1.5mm 2 The conductor is prepared by mixing modified polyvinyl chloride resin, inorganic filler, flame retardant, antioxidant, plasticizer and lubricant wrapped in a shell, and then melt-extruded at 220° C. outside the conductor with an extrusion thickness of 0.8 mm. The composite modified polyvinyl chloride soft cable is obtained by cooling and forming.

[0029] Example 2 A composite modified polyvinyl chloride flexible cable. The raw materials of the composite modified polyvinyl chloride flexible cable of this embodiment include, by weight, 70 parts of modified polyvinyl chloride resin, 30 parts of inorganic filler, 15 parts of shell-wrapped flame retardant, 5 parts of antioxidant, 3 parts of plasticizer, and 3 parts of lubricant.

[0030] The preparation method of the modified polyvinyl chloride resin of the present embodiment is: Polyvinyl chloride resin, dibenzoyl peroxide, p-aminobenzenesulfonic acid and methanol were mixed in a mass ratio of 4.1:0.04:0.65:11.5, stirred at 65° C. for 2.5 h, rinsed with deionized water and dried to obtain modified polyvinyl chloride resin.

[0031] The inorganic filler of this embodiment includes 2 parts of silicon dioxide, 1.5 parts of calcium carbonate, 1.6 parts of magnesium hydroxide, and 1.7 parts of mica by weight. The inorganic filler of this embodiment is obtained by mixing various raw materials and putting them into a ball mill, and ball milling them at a speed of 500 rpm for 6 hours.

[0032] The method for preparing the shell-wrapped flame retardant of this embodiment comprises the following steps: X1. Calcium stearate, zinc stearate and toluene were mixed in a mass ratio of 1:1:10, stirred at 320 rpm for 40 min, and isopropyl tri(dioctyl pyrophosphate) titanate was added dropwise at a rate of 5 ml / min, with a dropwise amount of 7 wt% of toluene added. The mixture was heated to 75°C and stirred at 450 rpm for 5 h to obtain solution A. X2. The composite flame retardant and solution A were mixed in a mass ratio of 1:3.2, stirred at 250 rpm for 30 min, and spray-dried to obtain a shell-wrapped flame retardant.

[0033] In step X2, the composite flame retardant of this embodiment is obtained by mixing flame retardant A and flame retardant B in a mass ratio of 1:1 and ball milling at a speed of 400 rpm for 5 hours.

[0034] The flame retardant A of this embodiment is obtained by mixing magnesium hydroxide, butyl orthosilicate and anhydrous ethanol in a mass ratio of 1:0.6:4, stirring at 85°C for 4.5 hours, and drying; the flame retardant B of this embodiment is obtained by mixing melamine and phosphoric acid in a mass ratio of 1:1.7, stirring at 130°C for 5.5 hours, and drying.

[0035] The spray drying parameters of this embodiment in step X2 are: inlet temperature is 160° C., outlet temperature is 110° C., and spray drying time is 2 h.

[0036] The plasticizer of this embodiment is prepared by mixing tributyl citrate, montmorillonite and anhydrous ethanol in a mass ratio of 1.8:1.5:10, stirring at 85° C. and 600 rpm for 4 hours, and drying to obtain the plasticizer.

[0037] The preparation method of the lubricant of this embodiment is: The carbon nanotubes and KH560 were mixed in a mass ratio of 1:0.07, stirred at 90°C for 3 hours, washed and dried to obtain the surface-treated carbon nanotubes; paraffin was heated at 85°C for 20 minutes, mixed with the surface-treated carbon nanotubes in a mass ratio of 1.5:0.8, and stirred at a speed of 1000 rpm for 1.5 hours to obtain a lubricant.

[0038] The antioxidant in this embodiment is antioxidant 1010.

[0039] The preparation method of the composite modified polyvinyl chloride flexible cable of this embodiment is: Seven strands of 0.2mm diameter copper wire are twisted to obtain a cross-sectional area of ​​1.5mm 2 The conductor is prepared by mixing modified polyvinyl chloride resin, inorganic filler, flame retardant, antioxidant, plasticizer and lubricant wrapped in a shell, and then melt-extruded at 260°C outside the conductor with an extrusion thickness of 0.8mm. The composite modified polyvinyl chloride soft cable is obtained by cooling and forming.

[0040] Example 3 A composite modified polyvinyl chloride flexible cable. The raw materials of the composite modified polyvinyl chloride flexible cable of this embodiment include 60 parts of modified polyvinyl chloride resin, 20 parts of inorganic filler, 10 parts of shell-wrapped flame retardant, 4 parts of antioxidant, 2.5 parts of plasticizer and 2.1 parts of lubricant by weight.

[0041] The preparation method of the modified polyvinyl chloride resin of the present embodiment is: Polyvinyl chloride resin, dibenzoyl peroxide, p-aminobenzenesulfonic acid and methanol were mixed in a mass ratio of 3.2:0.03:0.51:9.5, stirred at 60°C for 2h, rinsed with deionized water and dried to obtain modified polyvinyl chloride resin.

[0042] The inorganic filler of this embodiment includes, by weight, 1.6 parts of silicon dioxide, 1.4 parts of calcium carbonate, 1.25 parts of magnesium hydroxide, and 1.4 parts of mica. The inorganic filler of this embodiment is obtained by mixing various raw materials and putting them into a ball mill, and ball milling them at a speed of 350 rpm for 5 hours.

[0043] The method for preparing the shell-wrapped flame retardant of this embodiment comprises the following steps: X1. Calcium stearate, zinc stearate and toluene were mixed in a mass ratio of 1:1:8, stirred at 300 rpm for 35 min, and isopropyl tri(dioctyl pyrophosphate) titanate was added dropwise at a dropping rate of 5 ml / min, with a drop amount of 6 wt% of toluene added, and the temperature was raised to 70°C, and stirred at 400 rpm for 4 h to obtain solution A; X2. The composite flame retardant and solution A were mixed in a mass ratio of 1:2.5, stirred at 200 rpm for 25 min, and spray-dried to obtain a shell-wrapped flame retardant.

[0044] In step X2, the composite flame retardant of this embodiment is obtained by mixing flame retardant A and flame retardant B in a mass ratio of 1:1 and ball milling at a speed of 350 rpm for 4 hours.

[0045] The flame retardant A of this embodiment is obtained by mixing magnesium hydroxide, butyl orthosilicate and anhydrous ethanol in a mass ratio of 1:0.5:3, stirring at 80°C for 4 hours, and drying; the flame retardant B of this embodiment is obtained by mixing melamine and phosphoric acid in a mass ratio of 1:1.6, stirring at 120°C for 5 hours, and drying.

[0046] The spray drying parameters of this embodiment in step X2 are: inlet temperature of 150° C., outlet temperature of 100° C., and spray drying time of 1.5 h.

[0047] The plasticizer of this embodiment is prepared by mixing tributyl citrate, montmorillonite and anhydrous ethanol in a mass ratio of 1.5:1:9, stirring at 80° C. and 400 rpm for 3.5 hours, and drying to obtain the plasticizer.

[0048] The preparation method of the lubricant of this embodiment is: The carbon nanotubes and KH560 were mixed in a mass ratio of 1:0.06, stirred at 80°C for 2 hours, washed and dried to obtain the surface-treated carbon nanotubes; paraffin was heated at 80°C for 15 minutes, mixed with the surface-treated carbon nanotubes in a mass ratio of 1.35:0.75, and stirred at 800 rpm for 1 hour to obtain a lubricant.

[0049] The antioxidant in this embodiment is antioxidant 1010.

[0050] The preparation method of the composite modified polyvinyl chloride flexible cable of this embodiment is: Seven strands of 0.2mm diameter copper wire are twisted to obtain a cross-sectional area of ​​1.5mm 2 The conductor is prepared by mixing modified polyvinyl chloride resin, inorganic filler, flame retardant, antioxidant, plasticizer and lubricant wrapped in a shell, and then melt-extruded at 220-260°C outside the conductor to a thickness of 0.8mm, and then cooled and formed to obtain a composite modified polyvinyl chloride soft cable.

[0051] Comparative Example 1 On the basis of Example 3, the polyvinyl chloride resin is not modified, and other conditions are consistent with those of Example 3.

[0052] Comparative Example 2 On the basis of Example 3, the flame retardant wrapped in the shell was removed and replaced with an equal weight of calcium stearate. Other conditions were the same as in Example 3.

[0053] Comparative Example 3 On the basis of Example 3, the flame retardant A in the composite flame retardant was removed and replaced with an equal weight of flame retardant B, and other conditions were consistent with Example 3.

[0054] Comparative Example 4 On the basis of Example 3, tributyl citrate was used to replace the plasticizer, and other conditions were consistent with those in Example 3.

[0055] Comparative Example 5 On the basis of Example 3, paraffin was used to replace the lubricant, and other conditions were consistent with those of Example 3.

[0056] The cables prepared in Examples 1-3 and Comparative Examples 1-5 were used as samples, and their tensile strength, elongation at break and flame retardant properties were tested. At the same time, the samples were U-bent 10 million times to observe whether the insulation layer was broken or the sheath was damaged under repeated bending. The test results are shown in Table 1.

[0057] Table 1 It can be seen from Table 1 that the flame retardant properties of the composite modified polyvinyl chloride flexible cables prepared in Examples 1-3 of the present invention are better than those in Comparative Examples 1-5, and in the case of repeated bending, there will be no problems such as insulation layer rupture or sheath damage. The present invention improves the performance of polyvinyl chloride at the molecular level by modifying the polyvinyl chloride resin and coordinating with inorganic fillers, flame retardants wrapped in shells, plasticizers, lubricants and other additives, so that the composite modified polyvinyl chloride flexible cable has good flame retardancy while meeting the requirements of different application scenarios.

[0058] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any indirect modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A composite modified polyvinyl chloride flexible cable, characterized in that: The raw materials of the composite modified polyvinyl chloride flexible cable include, by weight, 50-70 parts of modified polyvinyl chloride resin, 10-30 parts of inorganic filler, 5-15 parts of shell-wrapped flame retardant, 3-5 parts of antioxidant, 2-3 parts of plasticizer, and 1.2-3 parts of lubricant.

2. A composite modified polyvinyl chloride flexible cable according to claim 1, characterized in that: The preparation method of the modified polyvinyl chloride resin is: The polyvinyl chloride resin, dibenzoyl peroxide, p-aminobenzenesulfonic acid and methanol are mixed in a mass ratio of 2.3-4.1:0.02-0.04:0.37-0.65:7.5-11.5, stirred at 55-65° C. for 1.5-2.5 hours, rinsed with deionized water and dried to obtain a modified polyvinyl chloride resin.

3. The composite modified polyvinyl chloride flexible cable according to claim 1, characterized in that: The inorganic filler comprises, by weight, 1.2-2 parts of silicon dioxide, 1.3-1.5 parts of calcium carbonate, 0.9-1.6 parts of magnesium hydroxide, and 1.1-1.7 parts of mica; the inorganic filler is obtained by mixing various raw materials, putting them into a ball mill, and milling them at a speed of 200-500 rpm for 4-6 hours.

4. The composite modified polyvinyl chloride flexible cable according to claim 1, characterized in that: The method for preparing the shell-wrapped flame retardant comprises the following steps: X1. Calcium stearate, zinc stearate and toluene were mixed in a mass ratio of 1:1:6-10, stirred at 280-320 rpm for 30-40 min, and isopropyl tri(dioctyl pyrophosphate) titanate was added dropwise at a rate of 5 ml / min, with a dropwise amount of 5-7 wt% of toluene added, and the temperature was raised to 65-75°C, and stirred at 350-450 rpm for 3-5 h to obtain solution A; X2. The composite flame retardant and solution A are mixed in a mass ratio of 1:1.8-3.2, stirred at a speed of 150-250 rpm for 20-30 min, and spray-dried to obtain a flame retardant wrapped in a shell layer.

5. A composite modified polyvinyl chloride flexible cable according to claim 4, characterized in that: The composite flame retardant in step X2 is obtained by mixing flame retardant A and flame retardant B in a mass ratio of 1:1 and ball milling at a speed of 300-400 rpm for 3-5 hours.

6. A composite modified polyvinyl chloride flexible cable according to claim 5, characterized in that: The flame retardant A is obtained by mixing magnesium hydroxide, butyl orthosilicate and anhydrous ethanol in a mass ratio of 1:0.4-0.6:2-4, stirring at 75-85°C for 3.5-4.5h, and drying; the flame retardant B is obtained by mixing melamine and phosphoric acid in a mass ratio of 1:1.5-1.7, stirring at 110-130°C for 4.5-5.5h, and drying.

7. The composite modified polyvinyl chloride flexible cable according to claim 4, characterized in that: The spray drying parameters of step X2 are: inlet temperature of 140-160°C, outlet temperature of 90-110°C, and spray drying time of 1-2h.

8. The composite modified polyvinyl chloride flexible cable according to claim 1, characterized in that: The plasticizer is prepared by mixing tributyl citrate, montmorillonite and anhydrous ethanol in a mass ratio of 1.2-1.8:0.5-1.5:8-10, stirring at 75-85° C. and 200-600 rpm for 3-4 hours, and drying to obtain the plasticizer.

9. The composite modified polyvinyl chloride flexible cable according to claim 1, characterized in that: The preparation method of the lubricant is: The carbon nanotubes and KH560 are mixed in a mass ratio of 1:0.05-0.07, stirred at 70-90°C for 1-3h, washed and dried to obtain the surface-treated carbon nanotubes; paraffin is heated at 75-85°C for 10-20min, mixed with the surface-treated carbon nanotubes in a mass ratio of 1.2-1.5:0.7-0.8, stirred at a speed of 600-1000rmp for 0.5-1.5h to obtain a lubricant.

10. A composite modified polyvinyl chloride flexible cable according to claim 1, characterized in that: The preparation method of the composite modified polyvinyl chloride flexible cable is as follows: A conductor is obtained by twisting 7 copper wires with a diameter of 0.2 mm. Modified polyvinyl chloride resin, inorganic filler, flame retardant wrapped in a shell, antioxidant, plasticizer and lubricant are mixed, melt-extruded outside the conductor at 220-260°C, and cooled to form a composite modified polyvinyl chloride soft cable.

Images