Environment-friendly halogen-free flame-retardant cable and preparation method thereof

Abstract

The invention discloses an environment-friendly halogen-free flame-retardant cable and a preparation method thereof.The environment-friendly halogen-free flame-retardant cable comprises a halogen-free flame-retardant outer layer, an armor layer and a plurality of cable cores, each cable core is composed of a plurality of stranded wires and an insulating layer, the insulating layer wraps the surfaces of the wires, the cable cores are wrapped by the armor layer, and the armor layer is wrapped by the outer layer. And the armor layer is coated by a halogen-free flame-retardant outer layer. Through the halogen-free flame-retardant outer layer, the halogen-free flame-retardant effect of the cable is improved, a large amount of toxic gas and smoke generated when the cable burns is avoided, the casualties caused by the toxic gas and smoke generated when the cable burns are reduced, meanwhile, pollution to the environment is reduced, and the environmental protection performance is improved; the flame-retardant cable has the advantages that the flame-retardant effect is excellent, the use safety and stability of the cable are improved, the aging resistance, heat insulation and corrosion resistance effects of the cable are improved, and the service life of the cable is effectively prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of cables, in particular to an environmentally friendly halogen-free flame-retardant cable and a preparation method thereof. Background Art

[0002] As an indispensable and important part of the power system, wires and cables play an irreplaceable role in daily life, commerce, and industry. With the continuous progress and development of society and the improvement of people's living standards, people pay more and more attention to safety in life. While pursuing a high-quality life, fire safety is becoming more and more important and urgent. According to reports on major fires, fires caused by spontaneous combustion of wires and cables account for a large proportion. PVC cable material is based on polyvinyl chloride resin, which is prepared by extrusion and other methods after adding other additives. Since PVC contains a large amount of chlorine, it has excellent flame retardant properties and is the main base material of cable materials. However, PVC will produce a large amount of toxic gas when it burns, which can easily cause casualties.

[0003] According to the application number: CN201820278415.9, the overhead insulated cable includes three single-core overhead insulated cables, and the single-core overhead insulated cables respectively include a conductive core, the conductive core is coated with a conductor shielding layer, and the conductor shielding layer is coated with a composite insulating sheath layer; the three single-core overhead insulated cables are arranged in an equilateral triangle, two single-core overhead insulated cables are arranged side by side at the bottom, and the third single-core overhead insulated cable is located in the square; two load-bearing steel strands are located on both sides of the third single-core overhead insulated cable; the two load-bearing steel strands and the three single-core overhead insulated cables are wrapped with covering tapes, and there must be an outer sheath outside the covering tapes.

[0004] The cable in the above case does not have the halogen-free flame retardant effect, resulting in a large amount of toxic gas and smoke generated when the cable burns, which can easily cause casualties and pollute the environment. For this reason, we provide an environmentally friendly halogen-free flame retardant cable and a preparation method thereof. Summary of the invention

[0005] The object of the present invention is to provide an environmentally friendly halogen-free flame-retardant cable and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an environmentally friendly halogen-free flame-retardant cable and a preparation method thereof, comprising a halogen-free flame-retardant outer layer, an armor layer and a plurality of cable cores, wherein the cable core is composed of a plurality of twisted conductors and an insulating layer, wherein the insulating layer is coated on the surface of the conductor, and the plurality of cable cores are coated by the armor layer, and the armor layer is coated by the halogen-free flame-retardant outer layer, wherein the armor layer can effectively improve the anti-extrusion, anti-stretching and anti-impact effects of the cable, and effectively protect the conductors inside the cable from damage, thereby improving the durability and service life of the cable, and at the same time, the armor layer is both strong and has a certain degree of flexibility, so that the cable can maintain good bending performance when subjected to external force, and will not harden or break due to external force;

[0007] The halogen-free flame-retardant outer layer is made of the following raw materials in parts by weight: 50-70 parts of ethylene-vinyl acetate copolymer, 10-20 parts of aluminum hydroxide, 10-20 parts of magnesium hydroxide, 5-10 parts of cross-linking agent, 2-6 parts of photoinitiator, 8-15 parts of antioxidant, 5-10 parts of lubricant, 2-8 parts of aluminum silicate, and 5-15 parts of compatibilizer.

[0008] Preferably, 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of crosslinking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate, and 5 parts of compatibilizer.

[0009] Preferably, 60 parts of ethylene-vinyl acetate copolymer, 15 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 7 parts of crosslinking agent, 4 parts of photoinitiator, 12 parts of antioxidant, 7 parts of lubricant, 5 parts of aluminum silicate, and 10 parts of compatibilizer.

[0010] Preferably, 70 parts of ethylene-vinyl acetate copolymer, 20 parts of aluminum hydroxide, 20 parts of magnesium hydroxide, 10 parts of crosslinking agent, 6 parts of photoinitiator, 15 parts of antioxidant, 10 parts of lubricant, 8 parts of aluminum silicate, and 15 parts of compatibilizer.

[0011] A method for preparing an environmentally friendly halogen-free flame-retardant cable, characterized in that it comprises the following steps:

[0012] S1. Material selection and processing: Select high-quality metal conductor copper, and according to the cable specifications, use extrusion and drawing equipment to process the metal conductor into the required shape and size, and then cover the surface of the metal conductor with an insulating layer to form a cable core, and then cover the surface of the cable core with an armor layer;

[0013] S2, halogen-free flame retardant preparation: select 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of cross-linking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate and 5 parts of compatibilizer;

[0014] S3, stirring and mixing: putting the ethylene-vinyl acetate copolymer, aluminum hydroxide, magnesium hydroxide and aluminum silicate prepared in S2 into a high-speed mixer for mixing and stirring, stirring at a temperature of 135-140° C. for 30-40 minutes and a speed of 700-1000 r / min to obtain a mixture A, then adding a crosslinking agent, a photoinitiator, an antioxidant, a lubricant and a compatibilizer to the mixture A, and continuing to stir for 20-30 minutes to obtain a mixture B;

[0015] S4, extrusion melt processing: transfer the mixture B obtained in S3 to a twin-screw extruder, extrude to obtain a halogen-free flame retardant material, melt-extrude the halogen-free flame retardant material, coat the surface of the armor layer, and after cooling and solidification, obtain a halogen-free flame retardant cable.

[0016] Preferably, the body temperature of the twin-screw extruder in S4 is 150-190°C, and the head temperature is 200-220°C.

[0017] Preferably, the finished halogen-free flame-retardant cable obtained in S4 is inspected, and qualified products are packaged and stored.

[0018] The halogen-free flame-retardant outer layer of the present invention has the following functions:

[0019] Ethylene-vinyl acetate copolymer: It is halogen-free, and has electrical insulation, softness, elasticity, chemical corrosion resistance and aging resistance. Ethylene-vinyl acetate copolymer can significantly improve the flame retardant properties of cables by adding aluminum hydroxide and magnesium hydroxide. It can isolate oxygen during combustion, thereby slowing down or preventing the combustion of cables, meeting the dual needs of safety and environmental protection in modern cable applications.

[0020] Aluminum hydroxide and magnesium hydroxide: have flame retardant effects and can be used as flame retardants. They are also environmentally friendly and pollution-free.

[0021] Cross-linking agent: It can improve the flame retardant properties of cables, reduce toxic smoke produced during combustion, protect the environment and personal safety, improve aging resistance, improve electrical properties, and enhance thermal stability and mechanical properties.

[0022] Photoinitiator: It enhances wear resistance and corrosion resistance, improves electrical insulation performance, ensures the stability and safety of the cable, and has environmental protection and energy-saving effects.

[0023] Antioxidant: It can delay aging, extend service life, improve safety, stability and maintain cable insulation performance.

[0024] Lubricant: It reduces friction and wear and can extend the service life of the cable.

[0025] Aluminum silicate: It has heat insulation and corrosion resistance effects, and aluminum silicate can effectively block the flow of current inside the cable, ensuring the safe operation of electrical equipment.

[0026] Compatibilizer: It can improve interface compatibility, enhance material properties, optimize processing performance and enhance flame retardant effect.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention improves the halogen-free flame retardant effect of the cable through the halogen-free flame retardant outer layer, avoids the generation of a large amount of toxic gas and smoke when the cable burns, reduces the phenomenon of casualties caused by the toxic gas and smoke generated by the burning of the cable, and reduces the pollution to the environment, improves the environmental protection performance, and has an excellent flame retardant effect. At the same time, it increases the safety and stability of the cable when in use, and increases the aging resistance, heat insulation and corrosion resistance of the cable, effectively extending the service life of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural cross-sectional view of the front view of the present invention.

[0030] In the figure: 1 halogen-free flame retardant outer layer, 2 armor layer, 3 cable core, 31 conductor, 32 insulation layer. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments 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 creative work are within the scope of protection of the present invention.

[0032] Implementation Column 1

[0033] See also Figure 1 An environmentally friendly halogen-free flame-retardant cable comprises a halogen-free flame-retardant outer layer 1, an armor layer 2 and a plurality of cable cores 3. The cable core 3 is composed of a plurality of twisted conductors 31 and an insulating layer 32. The insulating layer 32 is coated on the surface of the conductors 31. The plurality of cable cores 3 are coated by the armor layer 2, and the armor layer 2 is coated by the halogen-free flame-retardant outer layer 1.

[0034] The halogen-free flame-retardant outer layer 1 is made of the following raw materials in parts by weight: 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of crosslinking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate, and 5 parts of compatibilizer.

[0035] A method for preparing an environmentally friendly halogen-free flame-retardant cable comprises the following steps:

[0036] S1. Material selection and processing: Select high-quality metal conductor copper, and according to the cable specifications, process the metal conductor into a shape and size that meets the requirements through extrusion and drawing equipment, cover the surface of the metal conductor with an insulating layer 32 to form a cable core 3, and then cover the surface of the cable core 3 with an armor layer 2.

[0037] S2. Preparation of halogen-free flame retardant: select 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of cross-linking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate and 5 parts of compatibilizer.

[0038] S3, stirring and mixing: put the ethylene-vinyl acetate copolymer, aluminum hydroxide, magnesium hydroxide and aluminum silicate prepared in S2 into a high-speed mixer for mixing and stirring, stir at a temperature of 135° C. for 30 minutes, and a speed of 700 r / min to obtain a mixture A, and then add a crosslinking agent, a photoinitiator, an antioxidant, a lubricant and a compatibilizer to the mixture A, and continue stirring for 20 minutes to obtain a mixture B.

[0039] S4, extrusion melt processing: transfer the mixture B obtained in S3 to a twin-screw extruder with a body temperature of 150°C and a head temperature of 200°C to obtain a halogen-free flame retardant material by extrusion, melt-extrude the halogen-free flame retardant material, coat the surface of the armor layer 2, and obtain a halogen-free flame retardant cable after cooling and solidification.

[0040] The finished halogen-free flame-retardant cables obtained in S4 are inspected and qualified products are packaged and put into storage.

[0041] Implementation column 2

[0042] See also Figure 1 An environmentally friendly halogen-free flame-retardant cable comprises a halogen-free flame-retardant outer layer 1, an armor layer 2 and a plurality of cable cores 3. The cable core 3 is composed of a plurality of twisted conductors 31 and an insulating layer 32. The insulating layer 32 is coated on the surface of the conductors 31. The plurality of cable cores 3 are coated by the armor layer 2, and the armor layer 2 is coated by the halogen-free flame-retardant outer layer 1.

[0043] The halogen-free flame-retardant outer layer 1 is made of the following raw materials in parts by weight: 60 parts of ethylene-vinyl acetate copolymer, 15 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 7 parts of crosslinking agent, 4 parts of photoinitiator, 12 parts of antioxidant, 7 parts of lubricant, 5 parts of aluminum silicate, and 10 parts of compatibilizer.

[0044] A method for preparing an environmentally friendly halogen-free flame-retardant cable comprises the following steps:

[0045] S1. Material selection and processing: Select high-quality metal conductor copper, and according to the cable specifications, process the metal conductor into a shape and size that meets the requirements through extrusion and drawing equipment, cover the surface of the metal conductor with an insulating layer 32 to form a cable core 3, and then cover the surface of the cable core 3 with an armor layer 2.

[0046] S2. Preparation of halogen-free flame retardant: select 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of cross-linking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate and 5 parts of compatibilizer.

[0047] S3, stirring and mixing: put the ethylene-vinyl acetate copolymer, aluminum hydroxide, magnesium hydroxide and aluminum silicate prepared in S2 into a high-speed mixer for mixing and stirring, stir at a temperature of 138° C. for 35 minutes, and a speed of 850 r / min to obtain a mixture A, and then add a crosslinking agent, a photoinitiator, an antioxidant, a lubricant and a compatibilizer to the mixture A, and continue stirring for 25 minutes to obtain a mixture B.

[0048] S4, extrusion melt processing: transfer the mixture B obtained in S3 to a twin-screw extruder with a body temperature of 170°C and a head temperature of 215°C to obtain a halogen-free flame retardant material by extrusion, melt-extrude the halogen-free flame retardant material, coat the surface of the armor layer 2, and obtain a halogen-free flame retardant cable after cooling and solidification.

[0049] The finished halogen-free flame-retardant cables obtained in S4 are inspected and qualified products are packaged and put into storage.

[0050] Implementation Column 3

[0051] See also Figure 1 An environmentally friendly halogen-free flame-retardant cable comprises a halogen-free flame-retardant outer layer 1, an armor layer 2 and a plurality of cable cores 3. The cable core 3 is composed of a plurality of twisted conductors 31 and an insulating layer 32. The insulating layer 32 is coated on the surface of the conductors 31. The plurality of cable cores 3 are coated by the armor layer 2, and the armor layer 2 is coated by the halogen-free flame-retardant outer layer 1.

[0052] The halogen-free flame-retardant outer layer 1 is made of the following raw materials in parts by weight: 70 parts of ethylene-vinyl acetate copolymer, 20 parts of aluminum hydroxide, 20 parts of magnesium hydroxide, 10 parts of a crosslinking agent, 6 parts of a photoinitiator, 15 parts of an antioxidant, 10 parts of a lubricant, 8 parts of aluminum silicate, and 15 parts of a compatibilizer.

[0053] A method for preparing an environmentally friendly halogen-free flame-retardant cable comprises the following steps:

[0054] S1. Material selection and processing: Select high-quality metal conductor copper, and according to the cable specifications, process the metal conductor into a shape and size that meets the requirements through extrusion and drawing equipment, cover the surface of the metal conductor with an insulating layer 32 to form a cable core 3, and then cover the surface of the cable core 3 with an armor layer 2.

[0055] S2. Preparation of halogen-free flame retardant: select 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of cross-linking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate and 5 parts of compatibilizer.

[0056] S3, stirring and mixing: put the ethylene-vinyl acetate copolymer, aluminum hydroxide, magnesium hydroxide and aluminum silicate prepared in S2 into a high-speed mixer for mixing and stirring, stir at a temperature of 1140° C. for 40 minutes, and a speed of 1000 r / min to obtain a mixture A, then add a cross-linking agent, a photoinitiator, an antioxidant, a lubricant and a compatibilizer to the mixture A, continue stirring for 30 minutes, and obtain a mixture B.

[0057] S4, extrusion melt processing: transfer the mixture B obtained in S3 to a twin-screw extruder with a body temperature of 190°C and a head temperature of 220°C to obtain a halogen-free flame retardant material by extrusion, melt-extrude the halogen-free flame retardant material, coat the surface of the armor layer 2, and obtain a halogen-free flame retardant cable after cooling and solidification.

[0058] The finished halogen-free flame-retardant cables obtained in S4 are inspected and qualified products are packaged and put into storage.

[0059] The halogen-free flame retardant outer layer 1 improves the halogen-free flame retardant effect of the cable, avoids the generation of a large amount of toxic gas and smoke when the cable burns, reduces casualties caused by toxic gas and smoke generated by cable burning, reduces pollution to the environment, improves environmental protection performance, and has excellent flame retardant effect. At the same time, it increases the safety and stability of the cable when in use, and increases the aging resistance, heat insulation and corrosion resistance of the cable, effectively extending the service life of the cable.

[0060] It can be seen from the above three implementation columns that implementation column 2 is the optimal solution, the flame retardant grade reaches the V0 standard of UL94 grade, the limiting oxygen index reaches 60%, and the tensile strength is 40MPa, which means that the halogen-free flame retardant and fireproof cable prepared in implementation column 2 of the present application has good halogen-free, flame retardant and heat-resistant properties, while maintaining good tensile resistance, aging resistance, heat insulation, corrosion resistance and stability, thus realizing an environmentally friendly halogen-free flame retardant cable.

[0061] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly halogen-free flame-retardant cable, characterized by: The cable core (3) comprises a halogen-free flame-retardant outer layer (1), an armor layer (2) and a plurality of cable cores (3), wherein the cable core (3) is composed of a plurality of twisted conductors (31) and an insulating layer (32), wherein the insulating layer (32) is coated on the surface of the conductor (31), and the plurality of cable cores (3) are coated by the armor layer (2), and the armor layer (2) is coated by the halogen-free flame-retardant outer layer (1); The halogen-free flame-retardant outer layer (1) is made of the following raw materials in parts by weight: 50-70 parts of ethylene-vinyl acetate copolymer, 10-20 parts of aluminum hydroxide, 10-20 parts of magnesium hydroxide, 5-10 parts of cross-linking agent, 2-6 parts of photoinitiator, 8-15 parts of antioxidant, 5-10 parts of lubricant, 2-8 parts of aluminum silicate, and 5-15 parts of compatibilizer.

2. The environmentally friendly halogen-free flame-retardant cable according to claim 1, characterized in that: 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of crosslinking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate, and 5 parts of compatibilizer.

3. The environmentally friendly halogen-free flame-retardant cable according to claim 2, characterized in that: 60 parts of ethylene-vinyl acetate copolymer, 15 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 7 parts of crosslinking agent, 4 parts of photoinitiator, 12 parts of antioxidant, 7 parts of lubricant, 5 parts of aluminum silicate, and 10 parts of compatibilizer.

4. The environmentally friendly halogen-free flame-retardant cable according to claim 3, characterized in that: 70 parts of ethylene-vinyl acetate copolymer, 20 parts of aluminum hydroxide, 20 parts of magnesium hydroxide, 10 parts of crosslinking agent, 6 parts of photoinitiator, 15 parts of antioxidant, 10 parts of lubricant, 8 parts of aluminum silicate, and 15 parts of compatibilizer.

5. A method for preparing an environmentally friendly halogen-free flame-retardant cable, characterized in that: The following steps are involved: S1. Material selection and processing: Select high-quality metal conductor copper, and according to the cable specifications, use extrusion and drawing equipment to process the metal conductor into a shape and size that meets the requirements, and coat the surface of the metal conductor with an insulating layer (32) to form a cable core (3), and then coat the armor layer (2) on the surface of the cable core (3); S2, halogen-free flame retardant preparation: select 50 parts of ethylene-vinyl acetate copolymer, 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 5 parts of cross-linking agent, 2 parts of photoinitiator, 8 parts of antioxidant, 5 parts of lubricant, 2 parts of aluminum silicate and 5 parts of compatibilizer; S3, stirring and mixing: putting the ethylene-vinyl acetate copolymer, aluminum hydroxide, magnesium hydroxide and aluminum silicate prepared in S2 into a high-speed mixer for mixing and stirring, stirring at a temperature of 135-140° C. for 30-40 minutes and a speed of 700-1000 r / min to obtain a mixture A, then adding a crosslinking agent, a photoinitiator, an antioxidant, a lubricant and a compatibilizer to the mixture A, and continuing to stir for 20-30 minutes to obtain a mixture B; S4, extrusion melt processing: the mixture B obtained in S3 is transferred to a twin-screw extruder, extruded to obtain a halogen-free flame retardant material, the halogen-free flame retardant material is melt-extruded, coated on the surface of the armor layer (2), cooled and solidified, to obtain a halogen-free flame retardant cable.

6. The method for preparing an environmentally friendly halogen-free flame-retardant cable according to claim 5, characterized in that: The body temperature of the twin-screw extruder in S4 is 150-190°C, and the head temperature is 200-220°C.

7. The method for preparing an environmentally friendly halogen-free flame-retardant cable according to claim 5, characterized in that: The finished halogen-free flame-retardant cables obtained in S4 are inspected and qualified products are packaged and put into storage.

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