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CN-122011565-A - Low-smoke halogen-free high-flame-retardance power cable and preparation method thereof

CN122011565ACN 122011565 ACN122011565 ACN 122011565ACN-122011565-A

Abstract

The invention provides a low-smoke halogen-free high-flame-retardance power cable and a preparation method thereof, wherein the low-smoke halogen-free high-flame-retardance power cable comprises, by weight, 25-40 parts of an ethylene-vinyl acetate copolymer, 15-25 parts of linear low-density polyethylene, 5-15 parts of metallocene polyethylene, 8-15 parts of a reactive phosphorus-nitrogen-silicon hybrid compatibilizer, 12-22 parts of low-temperature sintered ceramic composite powder, 30-45 parts of surface-treated magnesium hydroxide, 15-25 parts of surface-treated aluminum hydroxide, 3-6 parts of organic modified montmorillonite, 1.5-2.5 parts of triallyl isocyanurate, 1.0-2.0 parts of a composite antioxidant, 1.0-2.5 parts of a calcium-zinc stabilizer and 0.5-1.5 parts of a silicone master batch. The low-smoke halogen-free high-flame-retardance power cable prepared by the invention has excellent flexibility, mechanical property, heat resistance and processability, and is stable in flame retardance and size, and suitable for power cable safety protection.

Inventors

  • WU YANLEI
  • WU CHONGFEI

Assignees

  • 北京市昆仑线缆制造有限公司

Dates

Publication Date
20260512
Application Date
20260306

Claims (9)

  1. 1. The low-smoke halogen-free high-flame-retardance power cable comprises a conductor, an insulating layer and a sheath layer, and is characterized in that the sheath layer is prepared from, by weight, 25-40 parts of ethylene-vinyl acetate copolymer, 15-25 parts of linear low-density polyethylene, 5-15 parts of metallocene polyethylene, 8-15 parts of reactive phosphazenium-silicon hybrid compatibilizer, 12-22 parts of low-temperature sintered ceramic composite powder, 30-45 parts of surface-treated magnesium hydroxide, 15-25 parts of surface-treated aluminum hydroxide, 3-6 parts of organic modified montmorillonite, 1.5-2.5 parts of triallyl isocyanurate, 1.0-2.0 parts of composite antioxidant, 1.0-2.5 parts of calcium-zinc stabilizer and 0.5-1.5 parts of silicone master batch.
  2. 2. The low-smoke halogen-free high-flame-retardance power cable disclosed by claim 1, wherein the preparation raw materials of the reactive phosphazene hybrid compatibilizer comprise, by weight, 95-105 parts of gamma-glycidol ether oxypropyl trimethoxysilane, 12-15 parts of deionized water, 0.5-0.8 part of 0.06-0.1 mol/L hydrochloric acid solution, 20-30 parts of melamine, 80-100 parts of absolute ethyl alcohol, 15-25 parts of pentaerythritol phosphate, 1-2 parts of p-toluenesulfonic acid and 0.5-1.0 part of dibutyltin dilaurate.
  3. 3. The low smoke zero halogen high flame retardant power cable of claim 2, wherein the preparation method of the reactive phosphazenium silicon hybrid compatibilizer comprises the following steps: 1) Mixing gamma-glycidoxypropyl trimethoxy silane, deionized water and a hydrochloric acid solution under the protection of nitrogen, stirring at a rotating speed of 150-250 r/min, performing hydrolytic condensation reaction for 4-6 hours at 25-30 ℃, heating to 80-90 ℃, and performing reduced pressure distillation at-0.08-0.1 MPa to remove small molecule byproducts to obtain hyperbranched polysiloxane with epoxy groups at the tail end; 2) Dispersing melamine in absolute ethyl alcohol, heating to 70-80 ℃, dropwise adding pentaerythritol phosphate, adding p-toluenesulfonic acid after the dropwise adding, carrying out reflux reaction for 4-6 hours at 80-85 ℃, cooling to 20-30 ℃, filtering, washing 2-3 times by absolute ethyl alcohol, and drying for 6-8 hours at 70-80 ℃ and vacuum degree of-0.08-0.1 MPa to obtain a phosphorus-nitrogen modifier; 3) Adding hyperbranched polysiloxane, a phosphorus-nitrogen modifier and dibutyl tin dilaurate into an internal mixer, and reacting for 5-8 min at the temperature of 150-160 ℃ and the rotating speed of 60-80 r/min to obtain the reactive phosphorus-nitrogen-silicon hybrid compatibilizer.
  4. 4. The low-smoke halogen-free high-flame-retardance power cable according to claim 1 is characterized in that the low-temperature sintering ceramic composite powder is prepared from 40-50 parts by weight of borosilicate glass powder, 20-30 parts by weight of ammonium polyphosphate, 15-20 parts by weight of wollastonite, 5-8 parts by weight of nano zinc oxide and 8-12 parts by weight of zirconium phosphate.
  5. 5. The low-smoke halogen-free high-flame-retardant power cable according to claim 4 is characterized in that the preparation method of the low-temperature sintering ceramic composite powder is characterized in that borosilicate glass powder, ammonium polyphosphate, wollastonite, nano zinc oxide and zirconium phosphate are placed in a planetary ball mill, absolute ethyl alcohol is used as a ball milling medium, the ball mass ratio is (3-5): 1, ball milling and mixing are carried out for 5-7 h at the rotating speed of 350-450 r/min, the mixed slurry is dried in vacuum for 10-14 h under the conditions of 80-90 ℃ and minus 0.08-0.1 MPa, and after crushing, the mixture is sieved by a 280-325 mesh sieve, and the low-temperature sintering ceramic composite powder is obtained.
  6. 6. The low smoke zero halogen high flame retardant power cable of claim 1, wherein the composite antioxidant is compounded by antioxidant 1010 and antioxidant 168 according to a mass ratio of 1:2.
  7. 7. A method of making a low smoke, halogen free, high flame retardant power cable according to any one of claims 1 to 6, comprising the steps of: s1, banburying and premixing: Mixing ethylene-vinyl acetate copolymer, linear low density polyethylene and metallocene polyethylene in proportion, putting the mixture into an internal mixer, and plasticizing the mixture for 3 to 5 minutes at the temperature of 100 to 110 ℃ and the speed of 40 to 50 r/min; Adding a reactive phosphorus nitrogen silicon hybrid compatibilizer, organic modified montmorillonite, a composite antioxidant and a calcium zinc stabilizer, and continuously mixing for 3-5 min at 110-120 ℃; adding surface-treated magnesium hydroxide, surface-treated aluminum hydroxide, low-temperature sintered ceramic composite powder and silicone master batch, mixing for 5-8 min at 120-130 ℃, and controlling the discharge temperature to be 130-140 ℃ to obtain mixed sizing material; S2, extrusion granulation: putting the mixed sizing material into a double-screw extruder, extruding and granulating, cooling, airing at room temperature, and granulating to obtain basic granules of the sheath layer; S3, blending and homogenizing a crosslinking auxiliary agent: Mixing the sheath layer basic granules with triallyl isocyanurate at 40-50 ℃ for 2-4 min to obtain sheath granules containing a crosslinking auxiliary agent; S4, cable molding: And extruding the sheath granules containing the crosslinking auxiliary agent through a single screw extruder to coat the metal shielding layer of the cable core to form a sheath layer, and placing the formed cable under an electron accelerator with the irradiation dose of 80-120 kGy for irradiation crosslinking to obtain the low-smoke halogen-free high-flame-retardance power cable.
  8. 8. The preparation method of the low-smoke zero-halogen high-flame-retardance power cable according to claim 7, wherein in the step S2, the temperatures of all sections of the extruder are set to be 130-140 ℃ in a first area, 140-150 ℃ in a second area, 150-160 ℃ in a third area, 155-165 ℃ in a fourth area, 150-160 ℃ in a machine head and the rotating speed of a screw rod is 250-350 r/min, and the extruded materials are cooled by circulating water at 15-25 ℃.
  9. 9. The method for manufacturing the low-smoke zero-halogen high-flame-retardance power cable according to claim 7, wherein in the step S4, the temperature of the extruder is set to be 140-150 ℃ in a feeding section, 150-160 ℃ in a compression section, 160-170 ℃ in a homogenizing section, 155-165 ℃ in a machine head and 1.2-2.0 mm in a sheath thickness.

Description

Low-smoke halogen-free high-flame-retardance power cable and preparation method thereof Technical Field The invention relates to the technical field of cables, in particular to a low-smoke halogen-free high-flame-retardance power cable and a preparation method thereof. Background The crosslinked polyethylene insulated power cable has been widely used in the power transmission fields of urban power grids, rail transit, high-rise buildings and the like by virtue of excellent electrical insulation performance, mechanical strength and heat-resistant stability, and becomes a main streamline cable product for medium-high voltage power transmission. In order to meet the fire safety requirements of public places and personnel-intensive areas, the outer sheath of the cable is made of low-smoke halogen-free flame-retardant materials, so that smoke release and toxic gas harm in a fire scene are reduced, and the running safety of a line is improved. At present, the conventional low-smoke halogen-free flame-retardant sheath material generally has the problems of insufficient comprehensive performance of matrix resin and poor compatibility of all components, is difficult to consider flexibility, mechanical strength, processing fluidity and low-temperature toughness, and meanwhile, has weak carbonizing effect of a system at high temperature, low interface bonding strength and insufficient melt strength, so that a stable and compact protective structure is difficult to form when the cable sheath is combusted, flame-retardant efficiency, high-temperature structural stability and dimensional stability are all to be improved, and the use requirements of a high-safety-grade power cable on low smoke, no halogen, high flame retardance and long-term reliability cannot be met. Disclosure of Invention Aiming at the problems in the prior art, the invention provides a low-smoke halogen-free high-flame-retardance power cable and a preparation method thereof. In order to achieve the above purpose, the invention is realized by the following technical scheme: The invention discloses a low-smoke halogen-free high-flame-retardance power cable which comprises, by weight, 25-40 parts of an ethylene-vinyl acetate copolymer, 15-25 parts of linear low-density polyethylene, 5-15 parts of metallocene polyethylene, 8-15 parts of a reactive phosphazene hybrid compatibilizer, 12-22 parts of low-temperature sintered ceramic composite powder, 30-45 parts of surface-treated magnesium hydroxide, 15-25 parts of surface-treated aluminum hydroxide, 3-6 parts of organic modified montmorillonite, 1.5-2.5 parts of triallyl isocyanurate, 1.0-2.0 parts of a composite antioxidant, 1.0-2.5 parts of a calcium zinc stabilizer and 0.5-1.5 parts of a silicone master batch. Preferably, the preparation raw materials of the reactive phosphazene hybrid compatibilizer comprise, by weight, 95-105 parts of gamma-glycidol ether oxypropyl trimethoxy silane, 12-15 parts of deionized water, 0.06-0.1 mol/L hydrochloric acid solution 0.5-0.8 parts of melamine, 20-30 parts of absolute ethyl alcohol, 80-100 parts of pentaerythritol phosphate, 15-25 parts of p-toluenesulfonic acid and 0.5-1.0 part of dibutyltin dilaurate. Preferably, the preparation method of the reactive phosphazenium-silicon hybrid compatibilizer comprises the following steps: 1) Mixing gamma-glycidoxypropyl trimethoxy silane, deionized water and a hydrochloric acid solution under the protection of nitrogen, stirring at a rotating speed of 150-250 r/min, performing hydrolytic condensation reaction for 4-6 hours at 25-30 ℃, heating to 80-90 ℃, and performing reduced pressure distillation at-0.08-0.1 MPa to remove small molecule byproducts to obtain hyperbranched polysiloxane with epoxy groups at the tail end; 2) Dispersing melamine in absolute ethyl alcohol, heating to 70-80 ℃, dropwise adding pentaerythritol phosphate, adding p-toluenesulfonic acid after the dropwise adding, carrying out reflux reaction for 4-6 hours at 80-85 ℃, cooling to 20-30 ℃, filtering, washing 2-3 times by absolute ethyl alcohol, and drying for 6-8 hours at 70-80 ℃ and vacuum degree of-0.08-0.1 MPa to obtain a phosphorus-nitrogen modifier; 3) Adding hyperbranched polysiloxane, a phosphorus-nitrogen modifier and dibutyl tin dilaurate into an internal mixer, and reacting for 5-8 min at the temperature of 150-160 ℃ and the rotating speed of 60-80 r/min to obtain the reactive phosphorus-nitrogen-silicon hybrid compatibilizer. Preferably, the preparation raw materials of the low-temperature sintered ceramic composite powder comprise 40-50 parts of borosilicate glass powder, 20-30 parts of ammonium polyphosphate, 15-20 parts of wollastonite, 5-8 parts of nano zinc oxide and 8-12 parts of zirconium phosphate by weight. Preferably, the preparation method of the low-temperature sintered ceramic composite powder comprises the steps of placing borosilicate glass powder, ammonium polyphosphate, wollastonite, nano zinc oxide and zirconium phosphate in a