Insulating flame-retardant polyarylene sulfide-based PVC cable and preparation process thereof

Abstract

The application relates to the technical field of cables, and discloses an insulating flame-retardant polyarylene sulfide-based PVC cable and a preparation process thereof. The PVC cable comprises an insulating sheath material and a wire core. The insulating sheath material contains silane coupling agent modified hexagonal boron nitride, modified polyphenylene sulfide and functionalized flame retardant. The functionalized flame retardant is prepared through Schiff base reaction and substitution reaction of 2,4,6-trihydroxybenzaldehyde, diethylenetriamine and diphenyl phosphinic chloride. The modified polyphenylene sulfide is prepared through copolymerization of sodium sulfide, p-dichlorobenzene and p-dichlorobenzoic acid. The PVC is grafted with maleic anhydride, the modified polyphenylene sulfide enhances the heat-resistant and flame-retardant framework, the silane coupling agent modified hexagonal boron nitride cooperatively insulates and conducts heat, and the functionalized flame retardant is used to construct a composite system integrating insulation, flame retardation and heat resistance. The obtained cable has excellent flame retardation, high-temperature resistance and mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of cable technology, specifically to an insulating and flame-retardant polyarylate sulfide-based PVC cable and its preparation process. Background Technology

[0002] Polyvinyl chloride (PVC) cables are widely used in power transmission, communications, building wiring, and automotive electronics due to their excellent electrical insulation properties, corrosion resistance, processing performance, and cost advantages. However, traditional PVC materials suffer from poor thermal stability, insufficient flame retardancy, and decreased insulation performance at high temperatures. Especially under overload or short-circuit conditions, they are prone to thermal decomposition, dripping, and even fires, limiting their application in high-end equipment, new energy vehicles, and special environments.

[0003] Polyaryl sulfide resins (such as polyphenylene sulfide, PPS) are ideal components for modifying high-performance polymers due to their excellent high-temperature resistance (long-term operating temperature >200℃), intrinsic flame retardancy (UL94 V-0 rating), good dimensional stability, and electrical insulation. However, the solubility parameters of PPS and PVC differ significantly, and direct blending can easily lead to interfacial delamination and stress concentration, which in turn reduces the mechanical strength and voltage withstand performance of cables. Furthermore, the high rigidity and low elongation at break of PPS significantly reduce the flexibility and bending performance of PVC cables.

[0004] Hexagonal boron nitride (h-BN) has high thermal conductivity, high resistivity and low dielectric constant, making it a potential filler for improving the insulation and heat dissipation performance of cables. However, unmodified h-BN has surface inertness and strong interlaminar forces, making it difficult to disperse evenly in PVC matrix. Furthermore, it has poor affinity with polymers and is prone to forming defect channels, which weakens the insulation performance.

[0005] In summary, existing technologies struggle to simultaneously achieve the flame retardancy, insulation reliability, heat resistance, and mechanical flexibility of PVC cables. Therefore, developing an insulating and flame-retardant PVC cable material that requires no high levels of flame retardant filler, exhibits good compatibility, and demonstrates excellent overall performance has significant engineering application value. This invention addresses these technical problems by employing maleic anhydride-grafted PVC for compatibilization, silane coupling agent-modified hexagonal boron nitride for synergistic thermal conductivity and insulation, modified polyphenylene sulfide to enhance the heat-resistant and flame-retardant framework, and incorporating functionalized flame retardants to construct an integrated polyaryl sulfide-based PVC composite system that combines insulation, flame retardancy, and heat resistance. Summary of the Invention

[0006] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an insulating and flame-retardant polyarylene sulfide-based PVC cable and its preparation process. The resulting PVC cable exhibits excellent flame retardancy, high-temperature resistance, and mechanical properties.

[0007] (II) Technical Solution An insulating and flame-retardant polyarylene sulfide-based PVC cable, the PVC cable comprising an insulating sheath material and a wire core; The insulating sheath material comprises the following raw materials in parts by weight: 100 parts by weight of PVC, 10-20 parts by weight of maleic anhydride-grafted PVC, 3-6 parts by weight of stabilizer, 30-50 parts by weight of DOP, 1-2 parts by weight of stearic acid, 5-10 parts by weight of silane coupling agent modified hexagonal boron nitride, 1-5 parts by weight of modified polyphenylene sulfide, and 2-5 parts by weight of functionalized flame retardant. Preferably, the preparation method of the modified polyphenylene sulfide includes the following steps: Sodium sulfide was dispersed in N-methylpyrrolidone and heated to 170°C to remove water. After the water removal was completed, the temperature was controlled at 160°C, and p-dichlorobenzene, p-dichlorobenzoic acid, and sodium hydroxide were added. Under a nitrogen atmosphere, the temperature was raised to 200-220°C and reacted for 3-5 hours. Then, the temperature was raised to 260-270°C and reacted for 2-3 hours. After the reaction was completed, the mixture was acidified with dilute hydrochloric acid, washed with deionized water and acetone, filtered, and dried to obtain modified polyphenylene sulfide.

[0008] The main types of polyarylene sulfide resins include polyphenylene sulfide, polyphenylene sulfide sulfone, polyphenylene sulfide ketone, and polyphenylene sulfide amide. This application uses polyphenylene sulfide as a raw material, modifies it, and adds it to PVC cables to make up for the defects of polyphenylene sulfide, such as high rigidity and low elongation at break, which reduce the mechanical properties of PVC cables.

[0009] Preferably, the mass ratio of sodium sulfide, p-dichlorobenzene, p-dichlorobenzoic acid, and sodium hydroxide is 1.3-1.5:1:0.09-0.1:0.02-0.03.

[0010] Preferably, the preparation method of the functionalized flame retardant includes the following steps: Step A1: Disperse 2,4,6-trihydroxybenzaldehyde in ethanol, stir to dissolve, add glacial acetic acid, stir for 20-30 min at room temperature, then add diethylenetriamine, react at room temperature for 2-3 h, raise the temperature to 70-75℃, stir for 5-7 h, after the reaction is complete, cool to room temperature, filter under reduced pressure, wash with ethanol, and dry to obtain the intermediate. The mass ratio of 2,4,6-trihydroxybenzaldehyde to diethylenetriamine is 2.9-3.2:1. In this reaction, the aldehyde group in 2,4,6-trihydroxybenzaldehyde reacts with the primary amine in diethylenetriamine to form a Schiff base reaction, and the reaction formula is as follows: ; Step A2: Add the intermediate, 4-dimethylaminopyridine, and triethylamine to chloroform, stir and disperse. Under nitrogen protection, add a chloroform solution of diphenylphosphine chloride, reflux for 24-26 hours. After the reaction is complete, wash, dry, filter, rotary evaporate, filter again, and wash to obtain the functionalized flame retardant. The mass ratio of the intermediate, diphenylphosphine chloride, and triethylamine is 1.5-1.8:1:0.4-0.5. In this reaction, the secondary amine contained in the intermediate undergoes a substitution reaction with diphenylphosphine chloride to obtain the functionalized flame retardant. The synthetic route is as follows: .

[0011] Preferably, the preparation method of the silane coupling agent modified hexagonal boron nitride includes the following steps: Dry hexagonal boron nitride was dispersed in an isopropanol deionized water solution, ultrasonically exfoliated for 10 h in an ultrasonic cleaner, centrifuged, filtered, and dried to obtain hydroxylated hexagonal boron nitride; the hydroxylated hexagonal boron nitride was added to a 75% (w / w) ethanol aqueous solution and ultrasonically dispersed for 1 h, then aminopropyltriethoxysilane was added, and the reaction was carried out at 100℃ under stirring and reflux for 24 h, filtered, washed with ethanol aqueous solution, and dried to obtain silane coupling agent modified hexagonal boron nitride.

[0012] In this process, boron nitride is modified using a silane coupling agent. The silane coupling agent acts as a "bridge," connecting the boron nitride surface and the PVC matrix, enhancing interfacial bonding, ensuring uniform dispersion of boron nitride particles, and preventing agglomeration. Boron nitride exhibits resistance to ultraviolet aging, blocking UV rays from damaging the PVC molecular chains, reducing aging, powdering, and cracking issues in outdoor cables, and improving weather resistance. It also possesses excellent thermal conductivity and insulation properties. Uniformly dispersed boron nitride can form thermal pathways within the PVC, rapidly dissipating heat, significantly improving the heat dissipation capacity of the sheath, reducing the long-term operating temperature of the cable, and extending its service life. Its insulation properties enhance the long-term insulation stability of the cable, making it suitable for high-voltage or high-insulation cable applications.

[0013] Preferably, the preparation process of the insulating flame-retardant polyarylether sulfide-based PVC cable includes the following steps: Weigh out the required amounts of PVC, maleic anhydride-grafted PVC, calcium zinc stabilizer, DOP, stearic acid, silane coupling agent modified hexagonal boron nitride, modified polyphenylene sulfide, and functionalized flame retardant, add them to a high-speed mixer, mix for 5 minutes, then pour them into an internal mixing extruder and mix at 165-170℃ for 10-15 minutes to obtain an insulating sheath material. Extrude it onto the surface of the armored wire core, cool and shape it to obtain an insulating flame retardant polyarylate sulfide-based PVC cable.

[0014] At this temperature, polyphenylene sulfide (PPS) does not completely melt and flow like PVC, but softens slightly and disperses uniformly in the molten PVC matrix as a solid filler, forming a typical "island structure". Ordinary PPS has poor compatibility with PVC, and direct mixing can easily lead to phase separation, affecting material properties. In this application, carboxyl groups are attached to the surface of PPS. Carboxyl groups can react with amino, hydroxyl, and other groups to form chemical bonds, preventing PPS from agglomerating in the PVC matrix, ensuring uniform dispersion, and forming a stable interface between PPS particles and PVC to transfer stress and improve the material's mechanical strength, heat resistance, and flame retardancy.

[0015] (iii) Beneficial technical effects This application uses 2,4,6-trihydroxybenzaldehyde, diethylenetriamine, and diphenylphosphine chloride as raw materials, and obtains a functionalized flame retardant through Schiff base reaction and substitution reaction. It contains a heat-resistant rigid benzene ring structure and a Schiff base structure. The Schiff base structure can absorb heat and undergo a thermal cross-linking reaction when heated, thereby improving the heat resistance of PVC cables. When the temperature rises further, a dense cross-linked carbon layer is generated, covering the material surface, which can isolate oxygen and heat and prevent the escape of combustible gases. The phosphorus element contained therein can produce a strong dehydrating substance when heated, which can promote the formation of a dense carbon layer and further prevent combustion.

[0016] This application uses maleic anhydride-grafted PVC (containing maleic anhydride structure), modified polyphenylene sulfide (containing carboxyl structure), silane coupling agent-modified hexagonal boron nitride (containing amino groups), and functionalized flame retardant (containing a large number of phenolic hydroxyl groups) as raw materials for cable materials. At high temperatures, the amino and hydroxyl groups can form chemical bonds with the maleic anhydride structure through ring-opening crosslinking and react with the carboxyl structure to form chemical bonds. This not only increases the compatibility of polyphenylene sulfide, boron nitride, and PVC matrix, but also generates more chemical crosslinking sites through the formation of more chemical bonds, increasing the crosslinking density of PVC cables. When subjected to external stress or friction, it can absorb and disperse stress and friction, thereby improving the comprehensive mechanical properties of PVC cables. Detailed Implementation

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The preparation method of silane coupling agent modified hexagonal boron nitride includes the following steps: 1.5 g of dried hexagonal boron nitride was dispersed in a 50% (w / w) isopropanol deionized water solution. The solution was ultrasonically exfoliated for 10 h in an ultrasonic cleaner, centrifuged, filtered, and dried to obtain hydroxylated hexagonal boron nitride. 0.2 g of hydroxylated hexagonal boron nitride was added to a 75% (w / w) ethanol aqueous solution and ultrasonically dispersed for 1 h. Then, 0.5 mL of aminopropyltriethoxysilane was added, and the mixture was stirred and refluxed at 100 °C for 24 h. The mixture was filtered, washed with ethanol aqueous solution, and dried to obtain silane coupling agent modified hexagonal boron nitride.

[0019] Example 1 Step A1: Disperse 30g of 2,4,6-trihydroxybenzaldehyde in ethanol, stir to dissolve, add 30mL of glacial acetic acid, stir for 30min at room temperature, then add 10.3g of diethylenetriamine, react at room temperature for 3h, raise the temperature to 75℃, stir for 6h, after the reaction is completed, cool to room temperature, filter under reduced pressure, wash with ethanol, and dry to obtain the intermediate; Step A2: Add 21g of the intermediate, 0.08g of 4-dimethylaminopyridine, and 5.5g of triethylamine to chloroform, stir and disperse. Under nitrogen protection, add 11.8g of a chloroform solution of diphenylphosphine chloride, reflux for 25h. After the reaction is complete, wash with saturated brine, dry, filter, rotary evaporate, let stand for a period of time and filter again, wash with ethyl acetate to obtain the functionalized flame retardant. Step A3: Disperse 40g of sodium sulfide into N-methylpyrrolidone, heat to 170℃ to remove water, and after the removal, control the temperature at 160℃. Add 30.2g of p-dichlorobenzene, 2.8g of p-dichlorobenzoic acid, and 0.8g of sodium hydroxide. Under a nitrogen atmosphere, raise the temperature to 210℃ and react for 4 hours. Then heat to 260℃ and react for 3 hours. After the reaction is complete, acidify with dilute hydrochloric acid, wash with deionized water and acetone respectively, filter, and dry to obtain modified polyphenylene sulfide. Step A4: Add PVC, maleic anhydride-grafted PVC, calcium-zinc stabilizer, DOP, stearic acid, silane coupling agent modified hexagonal boron nitride, modified polyphenylene sulfide, and functionalized flame retardant to a high-speed mixer and mix for 5 minutes. Then pour the mixture into a kneading extruder and mix at 170°C for 10 minutes to obtain an insulating sheath material. Extrude the material onto the surface of the armored wire core and cool to form an insulating flame-retardant polyaryl sulfide-based PVC cable. The insulating sheath material comprises the following parts by weight: 100 parts by weight of PVC, 10 parts by weight of maleic anhydride-grafted PVC, 3 parts by weight of calcium-zinc stabilizer, 50 parts by weight of DOP, 1 part by weight of stearic acid, 5 parts by weight of silane coupling agent modified hexagonal boron nitride, 1 part by weight of modified polyphenylene sulfide, and 2 parts by weight of functionalized flame retardant.

[0020] Example 2 Step A1: Disperse 32g of 2,4,6-trihydroxybenzaldehyde in ethanol, stir to dissolve, add 30mL of glacial acetic acid, stir at room temperature for 20min, then add 10.3g of diethylenetriamine, react at room temperature for 2h, heat to 70℃, stir to react for 7h, after the reaction is completed, cool to room temperature, filter under reduced pressure, wash with ethanol, dry to obtain intermediate; Step A2: Add 20g of the intermediate, 0.09g of 4-dimethylaminopyridine, and 5.5g of triethylamine to chloroform, stir and disperse. Under nitrogen protection, add 11.8g of a chloroform solution of diphenylphosphine chloride, reflux for 26h. After the reaction is complete, wash with saturated brine, dry, filter, rotary evaporate, let stand for a period of time and filter again, wash with ethyl acetate to obtain the functionalized flame retardant. Step A3: Disperse 42g of sodium sulfide into N-methylpyrrolidone, heat to 170℃ to remove water, and after the removal, control the temperature at 160℃. Add 30.2g of p-dichlorobenzene, 2.8g of p-dichlorobenzoic acid, and 0.8g of sodium hydroxide. Under a nitrogen atmosphere, heat to 200℃ and react for 5 hours. Then heat to 270℃ and react for 2 hours. After the reaction is complete, acidify with dilute hydrochloric acid, wash with deionized water and acetone respectively, filter, and dry to obtain modified polyphenylene sulfide. Step A4: Add PVC, maleic anhydride-grafted PVC, calcium-zinc stabilizer, DOP, stearic acid, silane coupling agent modified hexagonal boron nitride, modified polyphenylene sulfide, and functionalized flame retardant to a high-speed mixer and mix for 5 minutes. Then pour the mixture into a kneading extruder and mix at 165°C for 15 minutes to obtain an insulating sheath material. Extrude the material onto the surface of the armored wire core and cool to form an insulating flame-retardant polyaryl sulfide-based PVC cable. The insulating sheath material comprises the following parts by weight of raw materials: 100 parts by weight of PVC, 15 parts by weight of maleic anhydride-grafted PVC, 5 parts by weight of calcium-zinc stabilizer, 40 parts by weight of DOP, 1 part by weight of stearic acid, 8 parts by weight of silane coupling agent modified hexagonal boron nitride, 3 parts by weight of modified polyphenylene sulfide, and 4 parts by weight of functionalized flame retardant.

[0021] Example 3 Step A1: Disperse 31g of 2,4,6-trihydroxybenzaldehyde in ethanol, stir to dissolve, add 30mL of glacial acetic acid, stir at room temperature for 25min, then add 10.3g of diethylenetriamine, react at room temperature for 2.5h, heat to 75℃, stir for 5h, after the reaction is complete, cool to room temperature, filter under reduced pressure, wash with ethanol, and dry to obtain the intermediate; Step A2: Add 18g of the intermediate, 0.08g of 4-dimethylaminopyridine, and 5g of triethylamine to chloroform, stir and disperse. Under nitrogen protection, add 11.8g of a chloroform solution of diphenylphosphine chloride, reflux for 24h. After the reaction is complete, wash with saturated brine, dry, filter, rotary evaporate, let stand for a period of time and filter again, wash with ethyl acetate to obtain the functionalized flame retardant. Step A3: Disperse 45g of sodium sulfide into N-methylpyrrolidone, heat to 170℃ to remove water, and after the removal, control the temperature at 160℃. Add 30.2g of p-dichlorobenzene, 3g of p-dichlorobenzoic acid, and 0.9g of sodium hydroxide. Under a nitrogen atmosphere, heat to 220℃ and react for 3 hours. Then heat to 265℃ and react for 3 hours. After the reaction is complete, acidify with dilute hydrochloric acid, wash with deionized water and acetone respectively, filter, and dry to obtain modified polyphenylene sulfide. Step A4: Add PVC, maleic anhydride-grafted PVC, calcium-zinc stabilizer, DOP, stearic acid, silane coupling agent modified hexagonal boron nitride, modified polyphenylene sulfide, and functionalized flame retardant to a high-speed mixer and mix for 5 minutes. Then pour the mixture into a kneading extruder and mix at 165°C for 15 minutes to obtain an insulating sheath material. Extrude the material onto the surface of the armored wire core and cool to form an insulating flame-retardant polyaryl sulfide-based PVC cable. The insulating sheath material comprises the following parts by weight of raw materials: 100 parts by weight of PVC, 20 parts by weight of maleic anhydride-grafted PVC, 6 parts by weight of calcium-zinc stabilizer, 50 parts by weight of DOP, 2 parts by weight of stearic acid, 10 parts by weight of silane coupling agent modified hexagonal boron nitride, 5 parts by weight of modified polyphenylene sulfide, and 5 parts by weight of functionalized flame retardant.

[0022] Comparative Example 1 The difference between this comparative example and Example 1 is that a commercially available polyphenylene sulfide was used instead of modified polyphenylene sulfide in step A4.

[0023] Comparative Example 2 The difference between this comparative example and Example 1 is that in step A4, a commercially available hexagonal boron nitride is used instead of a silane coupling agent to modify the hexagonal boron nitride.

[0024] Comparative Example 3 The difference between this comparative example and Example 1 is that step A4 does not contain functionalized flame retardants.

[0025] Comparative Example 4 The difference between this comparative example and Example 1 is that step A4 does not contain maleic anhydride-grafted PVC.

[0026] The insulating sheath material was placed in a tablet press at 170°C for tableting, held under pressure for 5 minutes, then removed and cold-pressed, cut into standard samples, and tested.

[0027] Thermogravimetric analysis was performed using a thermogravimetric analyzer. Under a nitrogen atmosphere, 10 mg of sample was placed in a crucible and heated to 800 °C at a heating rate of 10 °C. Tensile properties were tested using an electronic universal testing machine. Test the LOI according to GB / T2406.2-2009.

[0028] Table 1: <![CDATA[T 5% / ℃]]> Tensile strength / MPa LOI / % Example 1 263.1 54.4 29.8 Example 2 270.8 57.7 30.9 Example 3 275.4 60.0 31.6 Comparative Example 1 259.0 50.3 28.3 Comparative Example 2 256.1 48.2 27.8 Comparative Example 3 251.3 49.6 26.0 Comparative Example 4 248.6 34.1 27.4 As shown in the table, the cable material prepared by this invention has good heat resistance, mechanical properties, and flame retardant properties. However, the performance of Comparative Example 4, which does not contain maleic anhydride-grafted PVC, is the worst. This is because maleic anhydride-grafted PVC acts as a bridge, linking the compatibility of the modified polyphenylene sulfide structure, the boron nitride structure, and the PVC substrate. Comparative Example 4 does not contain this bridge, so the interface defects between the modified polyphenylene sulfide structure and the boron nitride structure and PVC are larger, resulting in the worst overall performance.

[0029] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. An insulating and flame-retardant polyarylate sulfide-based PVC cable, characterized in that, The PVC cable includes an insulating sheath material and a wire core; The insulating sheath material comprises the following raw materials in parts by weight: 100 parts by weight of PVC, 10-20 parts by weight of maleic anhydride-grafted PVC, 3-6 parts by weight of stabilizer, 30-50 parts by weight of DOP, 1-2 parts by weight of stearic acid, 5-10 parts by weight of silane coupling agent modified hexagonal boron nitride, 1-5 parts by weight of modified polyphenylene sulfide, and 2-5 parts by weight of functionalized flame retardant.

2. The insulated and flame-retardant polyarylate sulfide-based PVC cable according to claim 1, characterized in that, The preparation method of the modified polyphenylene sulfide includes the following steps: Sodium sulfide was dispersed in N-methylpyrrolidone and heated to 170°C to remove water. After the water removal was completed, the temperature was controlled at 160°C, and p-dichlorobenzene, p-dichlorobenzoic acid, and sodium hydroxide were added. Under a nitrogen atmosphere, the temperature was raised to 200-220°C and reacted for 3-5 hours. Then, the temperature was raised to 260-270°C and reacted for 2-3 hours. After the reaction was completed, the mixture was acidified with dilute hydrochloric acid, washed with deionized water and acetone, filtered, and dried to obtain modified polyphenylene sulfide.

3. The insulated and flame-retardant polyarylate sulfide-based PVC cable according to claim 2, characterized in that, The mass ratio of sodium sulfide, p-dichlorobenzene, p-dichlorobenzoic acid, and sodium hydroxide is 1.3-1.5:1:0.09-0.1:0.02-0.

03.

4. The insulated and flame-retardant polyarylate sulfide-based PVC cable according to claim 1, characterized in that, The preparation method of the functionalized flame retardant includes the following steps: Step A1: Disperse 2,4,6-trihydroxybenzaldehyde in ethanol, stir to dissolve, add glacial acetic acid, stir at room temperature for 20-30 min, then add diethylenetriamine, react at room temperature for 2-3 h, raise the temperature to 70-75℃, stir to react for 5-7 h, after the reaction is completed, cool to room temperature, filter under reduced pressure, wash with ethanol, and dry to obtain the intermediate; Step A2: Add the intermediate, 4-dimethylaminopyridine, and triethylamine to chloroform, stir and disperse. Under nitrogen protection, add a chloroform solution of diphenylphosphine chloride, reflux for 24-26 hours. After the reaction is complete, wash, dry, filter, rotary evaporate, filter again, wash, and obtain the functionalized flame retardant.

5. The insulated and flame-retardant polyarylate sulfide-based PVC cable according to claim 4, characterized in that, In step A1, the mass ratio of 2,4,6-trihydroxybenzaldehyde to diethylenetriamine is 2.9-3.2:

1.

6. The insulated flame-retardant polyarylate sulfide-based PVC cable according to claim 4, characterized in that, In step A2, the mass ratio of the intermediate, diphenylphosphine chloride, and triethylamine is 1.5-1.8:1:0.4-0.

5.

7. The insulated and flame-retardant polyarylate sulfide-based PVC cable according to claim 1, characterized in that, The preparation method of the silane coupling agent modified hexagonal boron nitride includes the following steps: Dry hexagonal boron nitride was dispersed in an isopropanol deionized water solution, ultrasonically exfoliated for 10 h in an ultrasonic cleaner, centrifuged, filtered, and dried to obtain hydroxylated hexagonal boron nitride; the hydroxylated hexagonal boron nitride was added to a 75% (w / w) ethanol aqueous solution and ultrasonically dispersed for 1 h, then aminopropyltriethoxysilane was added, and the reaction was carried out at 100℃ under stirring and reflux for 24 h, filtered, washed with ethanol aqueous solution, and dried to obtain silane coupling agent modified hexagonal boron nitride.

8. A manufacturing process for an insulating flame-retardant polyarylate sulfide-based PVC cable as described in any one of claims 1-7 comprises the following steps: Weigh out the required amounts of PVC, maleic anhydride-grafted PVC, calcium zinc stabilizer, DOP, stearic acid, silane coupling agent modified hexagonal boron nitride, modified polyphenylene sulfide, and functionalized flame retardant, add them to a high-speed mixer, mix for 5 minutes, then pour them into an internal mixing extruder and mix at 165-170℃ for 10-15 minutes to obtain an insulating sheath material. Extrude it onto the surface of the armored wire core, cool and shape it to obtain an insulating flame retardant polyarylate sulfide-based PVC cable.