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CN-122025257-A - High-strength mineral insulation fireproof cable

CN122025257ACN 122025257 ACN122025257 ACN 122025257ACN-122025257-A

Abstract

The invention discloses a high-strength mineral insulation fireproof cable, which belongs to the technical field of cable processing and is used for solving the technical problems that the mineral insulation material doping amount in the mineral insulation fireproof cable in the prior art is low, the insulation performance, the flame retardant performance and the combustion performance of the cable are required to be further improved and the mechanical performance of the cable is poor; the invention comprises a plurality of wire cores, a filling layer, a flame retardant belt, a mineral fireproof layer and an outer sheath layer which are sequentially arranged from inside to outside, the heat insulation protection layer taking the filler layer as the wire core is formed, the flame retardant belt is used as a support, the mineral fireproof layer and the outer sheath layer are insulation fireproof layers of the cable, and the fireproof performance, the flame retardant performance, the insulation performance and the mechanical performance of the mineral insulation fireproof cable are effectively improved.

Inventors

  • SHI XUPENG
  • LV XICHEN
  • YANG ZHAOFENG
  • WANG BO

Assignees

  • 江苏远通电缆有限公司

Dates

Publication Date
20260512
Application Date
20260109

Claims (10)

  1. 1. The high-strength mineral insulation fireproof cable is characterized by comprising a plurality of wire cores (1), a filling layer (2), a flame retardant belt (3), a mineral fireproof layer (4) and an outer sheath layer (5) which are sequentially arranged from inside to outside; The filling layer (2) is formed by filling mixed filler formed by mixing mixed powder and epoxy resin according to a weight ratio of 2:1 into the flame-retardant belt (3) and solidifying and forming, wherein the mixed powder consists of fly ash, glass beads, aluminum silicate and calcium hydroxide according to a weight ratio of 1:3:2:2, and the granularity of the mixed powder is 200-260 mu m; the flame-retardant belt (3) is an alumina thin belt, and the thickness of the alumina thin belt is 0.3-0.6mm; The mineral fireproof layer (4) is prepared by uniformly mixing low-density polyethylene, reinforced mineral powder and an additive according to a weight ratio of 10:4:0.3, adding the mixture into a first twin-screw extruder, carrying out melt extrusion, coating the mixture on the outside of the flame-retardant belt (3), and curing and forming the mixture; The outer sheath layer (5) is prepared by uniformly mixing low-density polyethylene, a compatilizer, silane composite microbeads and an additive in a weight ratio of 10:3:4:0.35, adding the mixture into a double-screw extruder II, and carrying out melt extrusion coating on the exterior of the mineral fireproof layer (4) and solidifying and forming.
  2. 2. The high strength mineral insulated fire rated cable of claim 1 wherein the enhanced mineral powder is produced by the steps of: A1, adding hydromagnesite, zinc borate and silicon powder into a ball mill, ball milling, and sieving with a 100-mesh sieve to obtain mixed mineral powder; a2, adding the mixed mineral powder, the 60vt percent ethanol solution and the catalyst into a reaction kettle, stirring, increasing the temperature of the reaction kettle to slightly reflux the system, dripping the modifier into the reaction kettle, carrying out heat preservation treatment for 3-5h after the dripping is finished, and carrying out post treatment to obtain modified mineral powder; A3, adding the phase-changing agent and the N, N-dimethylacetamide into a reaction kettle, stirring until the system is dissolved, adding the modified mineral powder into the reaction kettle in batches, raising the temperature of the reaction kettle until the system flows back, carrying out heat preservation reaction for 4-6h, and carrying out post-treatment to obtain the enhanced mineral powder.
  3. 3. The high-strength mineral-insulated fireproof cable according to claim 2, wherein the weight ratio of hydromagnesite, zinc borate and silicon powder in the step A1 is 6:2:3, the use amount ratio of the mixed mineral powder, the 60vt% ethanol solution, the catalyst and the modifier in the step A2 is 3g:15mL:0.3g:2g, the catalyst is potassium hydroxide, the modifier is 2- (3, 4-epoxycyclohexane) ethyltrimethoxysilane, and the use amount ratio of the compatilizer, N-dimethylacetamide and the modified mineral powder in the step A3 is 3g:15mL:2g.
  4. 4. The high strength mineral insulated fire rated cable of claim 1 wherein the compatibilizer is processed by the steps of: B1, adding toluene and a catalyst into a reaction kettle filled with ethylene, stirring, continuously introducing ethylene into the reaction kettle, raising the temperature of the reaction kettle to 50-60 ℃, carrying out heat preservation reaction for 4-6 hours, adding acidified ethanol into the reaction kettle, terminating the reaction, and carrying out post-treatment to obtain single-end double-bond polyethylene; Adding single-end double-bond polyethylene and chlorobenzene into a reaction kettle protected by nitrogen, stirring, heating the reaction kettle to 90-100 ℃, keeping the temperature, stirring until the system is dissolved, adding 3-mercaptopropionic acid and an initiator into the reaction kettle, keeping the temperature, reacting for 4-6 hours, and performing post-treatment to obtain modified polyethylene; Adding the modified polyethylene and toluene into a reaction kettle protected by nitrogen, stirring, increasing the temperature of the reaction kettle to 100-110 ℃, stirring until the system is dissolved, adding dihydroxy-terminated polydimethylsiloxane and a catalyst into the reaction kettle, carrying out heat preservation reaction for 4-6h, and carrying out post-treatment to obtain the composite polyethylene; And B4, adding the composite polyethylene, the modifier, the initiator, the styrene and the toluene into a high-pressure reaction kettle protected by nitrogen, stirring, heating the high-pressure reaction kettle to 140-150 ℃, carrying out heat preservation reaction for 6-7 hours, reducing the temperature of the high-pressure reaction kettle to 60-70 ℃, adding trifluoroacetic acid into the high-pressure reaction kettle, carrying out heat preservation reaction for 2-3 hours, and carrying out post-treatment to obtain the compatilizer.
  5. 5. The high-strength mineral-insulated fireproof cable according to claim 4, wherein the dosage ratio of toluene, catalyst and acidified ethanol in step B1 is 100mL:1g:10mL, the catalyst is composed of a cocatalyst dMAO (Al/Zr=2000) and a main catalyst PTFI in a weight ratio of 90:1, the acidified ethanol is composed of 30wt% hydrochloric acid and absolute ethanol in a weight ratio of 1:3, the post-treatment operation comprises adding absolute ethanol into a reaction kettle after the reaction is completed, stirring for 6-8h at room temperature, filtering, washing a filter cake with absolute ethanol three times, transferring the filter cake into a drying oven with a temperature of 50-60 ℃ and drying to constant weight, and obtaining single-end double-bond polyethylene, wherein the dosage ratio of single-end double-bond polyethylene, chlorobenzene, 3-mercaptopropionic acid and an initiator in step B2 is 10g:30mL:12mL:0.5g, the initiator is azodiisobutyronitrile, the modified polyethylene, toluene, dihydroxypolydimethylsiloxane and catalyst in step B3 is 15 g, and the initiator in a dosage ratio of 15:2 g of toluene and 2g of styrene in a ratio of 100mL, and the initiator in a dosage ratio of 5 mg/2 g of toluene and 2g of styrene in step B2:2 g.
  6. 6. The high-strength mineral insulated fireproof cable according to claim 4, wherein the modifier is prepared by adding tert-butyl alcohol, cyclohexane and a catalyst into a nitrogen-protected reaction kettle, stirring, heating the reaction kettle to 45-50 ℃, adding p-isopropenyl dimethylbenzyl isocyanate into the reaction kettle, reacting for 6-8 hours under heat preservation, and performing post-treatment.
  7. 7. The high strength mineral insulated fire protection cable of claim 6, wherein the ratio of t-butanol to p-isopropenyldimethylbenzyl isocyanate is 1 mol/1 mol, the ratio of t-butanol, cyclohexane and catalyst is 1 g/7 ml/0.1 g, the catalyst is dibutyltin dilaurate, and the post-treatment comprises removing solvent by distillation under reduced pressure after the reaction is completed to obtain the modifier.
  8. 8. The high-strength mineral-insulated fireproof cable according to claim 1, wherein the preparation method of the silane composite microbeads comprises the steps of adding vinyl-terminated polydimethylsiloxane, 3-chloropropyl trimethoxysilane and N, N-dimethylformamide into a reaction kettle protected by nitrogen, stirring for dissolution, adding a catalyst into the reaction kettle, raising the temperature of the reaction kettle to 120-130 ℃, carrying out heat preservation for 6-8 hours, reducing the temperature of the reaction kettle to 65-75 ℃, adding glass microbead dispersion liquid into the reaction kettle, carrying out heat preservation for 2-3 hours, and carrying out post treatment to obtain the silane composite microbeads.
  9. 9. The high-strength mineral-insulated fireproof cable according to claim 8, wherein the vinyl-terminated polydimethylsiloxane, 3-chloropropyl trimethoxysilane, N-dimethylformamide, catalyst and glass bead dispersion are used in an amount ratio of 4g to 1g to 12mL to 0.01g to 6g, the catalyst is chloroplatinic acid, and the glass bead dispersion is prepared by uniformly mixing glass beads with a particle size of 150-200 μm and a wall thickness of 1-2 μm, purified water and a surfactant in a weight ratio of 1:10:0.1.
  10. 10. The high-strength mineral-insulated fireproof cable according to claim 1, wherein the additive consists of an antioxidant, a lubricant and a plasticizer in a weight ratio of 1:1:3, wherein the antioxidant is antioxidant 702, the lubricant is one or more of calcium stearate, zinc stearate and sodium stearate, the plasticizer is dioctyl phthalate, the temperatures of 8 temperature sections of the twin-screw extruder, which are arranged from the feeding end towards the machine head, are sequentially 170 ℃, 180 ℃, 190 ℃, 180 ℃ and 170 ℃, the main shaft rotating speed of the twin-screw extruder is 15r/min, the temperatures of 8 temperature sections of the double-screw extruder II, which are arranged from the feeding end towards the machine head, are sequentially 170 ℃, 180 ℃, 190 ℃, 180 ℃ and 170 ℃, and the spindle rotating speed of the double-screw extruder is 15r/min.

Description

High-strength mineral insulation fireproof cable Technical Field The invention relates to the technical field of cable processing, in particular to a high-strength mineral insulation fireproof cable. Background The cable is widely applied in the fields of energy, traffic, communication, electric power and the like, the mineral insulating material has the advantages of high temperature resistance, thermal shock resistance, no halogen, chemical corrosion resistance and the like, the electrical property and the mechanical strength of the cable can be kept in a high-temperature environment, and the mineral insulating fireproof cable is used as a novel fireproof cable and is widely applied to various places with excellent fireproof property and high mechanical strength; In the prior art, the mineral insulating fireproof cable is generally prepared by uniformly mixing a mineral insulating material in a filler form with matrix resins such as polyethylene, polyvinyl chloride and the like in a heating blending form, however, the mineral insulating material is generally an inorganic material, the compatibility between the mineral insulating material and the matrix resins is poor, the dispersibility of the mineral insulating material in the matrix resins is poor, the doping amount of the mineral insulating material is low, the insulating property, the flame retardant property and the combustion property of the cable are required to be further improved, and a weak interface exists on the mineral insulating fireproof cable due to the poor compatibility between the mineral insulating material and the matrix resins, so that the mechanical property of the cable is required to be further improved; In view of the technical drawbacks of this aspect, a solution is now proposed. Disclosure of Invention The invention aims to provide a high-strength mineral insulation fireproof cable, which is used for solving the technical problems that the mineral insulation material in the mineral insulation fireproof cable in the prior art is low in doping amount, the insulation performance, the flame retardant performance and the combustion performance of the cable are required to be further improved and the mechanical performance of the cable is poor. The high-strength mineral insulation fireproof cable comprises a plurality of wire cores, a filling layer, a flame retardant belt, a mineral fireproof layer and an outer sheath layer which are sequentially arranged from inside to outside; The filling layer is formed by filling mixed filler formed by mixing mixed powder and epoxy resin according to a weight ratio of 2:1 into a flame-retardant belt, and curing and forming, wherein the mixed powder consists of fly ash, glass beads, aluminum silicate and calcium hydroxide according to a weight ratio of 1:3:2:2, and the granularity of the mixed powder is 200-260 mu m; The flame-retardant belt is an alumina thin belt, and the thickness of the flame-retardant belt is 0.3-0.6mm; The mineral fireproof layer is prepared by uniformly mixing low-density polyethylene, reinforced mineral powder and an additive according to a weight ratio of 10:4:0.3, adding the mixture into a first twin-screw extruder, carrying out melt extrusion, coating the mixture outside a flame-retardant belt, and carrying out solidification molding; The outer sheath layer is prepared by uniformly mixing low-density polyethylene, a compatilizer, silane composite microbeads and an additive in a weight ratio of 10:3:4:0.35, adding the mixture into a second double-screw extruder, and carrying out melt extrusion coating on the exterior of the mineral fireproof layer, and solidifying and forming. Further, the enhanced mineral powder is obtained by processing the following steps: A1, adding hydromagnesite, zinc borate and silicon powder into a ball mill, ball milling, and sieving with a 100-mesh sieve to obtain mixed mineral powder; a2, adding the mixed mineral powder, the 60vt percent ethanol solution and the catalyst into a reaction kettle, stirring, increasing the temperature of the reaction kettle to slightly reflux the system, dripping the modifier into the reaction kettle, carrying out heat preservation treatment for 3-5h after the dripping is finished, and carrying out post treatment to obtain modified mineral powder; the synthesis reaction principle of the modified mineral powder is as follows: In the formula, Is mixed mineral powder particles. The siloxane bond is hydrolyzed under alkaline condition to generate silicon hydroxyl, and can react with active functional groups on the mixed mineral powder to form stable chemical connection, so that epoxy groups are modified on the surface of the mixed mineral powder, and the reactivity of the modified mineral powder is improved. A3, adding the phase-changing agent and the N, N-dimethylacetamide into a reaction kettle, stirring until the system is dissolved, adding the modified mineral powder into the reaction kettle in batches, raising th