Search

CN-122011548-A - High-toughness XLPE overhead insulated cable and preparation method thereof

CN122011548ACN 122011548 ACN122011548 ACN 122011548ACN-122011548-A

Abstract

The application relates to the technical field of insulated cables, in particular to a high-toughness XLPE overhead insulated cable and a preparation method thereof, wherein the high-toughness XLPE overhead insulated cable comprises a cable core and an insulating layer, the insulating layer is prepared from the following raw materials, by weight, 50-60 parts of low-density polyethylene, 15-25 parts of linear low-density polyethylene, 15-25 parts of high-density polyethylene, 8-12 parts of modified nano inorganic filler, 6-14 parts of double-end vinyl silicone oil, 8-12 parts of initiator, 0.5-1 part of light stabilizer, 0.1-1 part of antioxidant and 0.2-1 part of lubricant, and the modified nano inorganic filler is prepared from nano inorganic filler through modification of a silane coupling agent and has the advantage of improving the toughness of the crosslinked polyethylene cable material.

Inventors

  • LU KANGNING
  • CHENG YANJUN

Assignees

  • 安徽明福电缆有限公司

Dates

Publication Date
20260512
Application Date
20260206

Claims (8)

  1. 1. The high-toughness XLPE overhead insulated cable is characterized by comprising a cable core and an insulating layer, wherein the insulating layer is prepared from the following raw materials, by weight, 50-60 parts of low-density polyethylene, 15-25 parts of linear low-density polyethylene, 15-25 parts of high-density polyethylene, 8-12 parts of modified nano inorganic filler, 6-14 parts of double-end vinyl silicone oil, 8-12 parts of initiator, 0.5-1 part of light stabilizer, 0.1-1 part of antioxidant and 0.2-1 part of lubricant; the modified nano inorganic filler is prepared by modifying nano inorganic filler through a silane coupling agent.
  2. 2. A high toughness XLPE overhead insulated cable according to claim 1, wherein the viscosity of the double-ended vinyl silicone oil is 1000-6000cSt.
  3. 3. The high-toughness XLPE overhead insulated cable according to claim 2, wherein the addition amount of the double-end vinyl silicone oil is 9.5-10.5 parts by weight.
  4. 4. The XLPE aerial insulated cable of claim 1, wherein the silane coupling agent is a vinyl silane coupling agent.
  5. 5. The XLPE aerial insulated cable of claim 4, wherein the vinyl silane coupling agent is one or more of vinyl triethoxysilane, acryloxymethyl trimethoxysilane, 7-octenyl trimethoxysilane, gamma-methacryloxypropyl trimethoxysilane, vinyl triisopropoxysilane, and vinyl tributylketoxime silane.
  6. 6. The XLPE aerial insulated cable of claim 1, wherein the inorganic nano filler has an average particle size of 50-200nm.
  7. 7. The high-toughness XLPE overhead insulated cable of claim 1, wherein the lubricant is zinc stearate.
  8. 8. A preparation method of the anti-aging composite polyvinyl chloride overhead insulated cable is characterized in that the high-toughness XLPE overhead insulated cable is prepared by preparing an insulating layer from an insulating material and then coating a cable core by the insulating layer, and the preparation method of the insulating material comprises the following steps: Uniformly mixing all the raw materials of the insulating material, feeding the mixture into a first-stage homodromous double-screw mixer of a double-stage mixing extruder unit for mixing and extruding, and keeping the mixture in a screw for 350-500s to obtain an extruded material, wherein the temperature of a feeding section is 135-150 ℃, the temperature of a compression section is 160-175 ℃, the temperature of a homogenizing section is 185-200 ℃ and the temperature of a discharging section is 160-170 ℃, and the rotating speed of a host machine is 400-600rpm; and (3) feeding the extrusion material into a second-stage single-screw extruder, setting the temperature of the single-screw extruder to be 125-140 ℃, extruding and granulating at the rotating speed of 100-300rpm, and obtaining the insulating material.

Description

High-toughness XLPE overhead insulated cable and preparation method thereof Technical Field The application relates to the technical field of insulated cables, in particular to a high-toughness XLPE overhead insulated cable and a preparation method thereof. Background The cable is a key device for direct current transmission, and the main raw materials of the cable comprise natural rubber, polyvinyl chloride, synthetic rubber, polyethylene, crosslinked polyethylene and the like. Among them, the crosslinked polyethylene is currently the mainstream insulating material because of its excellent heat resistance and mechanical properties, and its long-term working temperature can reach 90 ℃. However, due to the three-dimensional network structure of the crosslinked polyethylene, the crosslinked structure limits the sliding and the orientation of molecular chains, so that when the material is subjected to external forces such as impact, bending or ground subsidence, cracks are easy to initiate and rapidly expand, the insulating layer is damaged, and the hidden danger of short circuit is caused. The existing method for toughening and modifying the crosslinked polyethylene is to add micro-or nano-scale inorganic filler to improve the rigidity and heat resistance of the material. However, the interfacial compatibility between the inorganic filler and the polymer matrix is poor, agglomeration is easy to occur, stress concentration is caused, and the inorganic filler and the polymer matrix can become crack sources, so that the toughness of the material is reduced. Disclosure of Invention In order to improve the toughness of the crosslinked polyethylene cable material, the application provides a high-toughness XLPE overhead insulated cable and a preparation method thereof. In a first aspect, the application provides a high-toughness XLPE overhead insulated cable, which adopts the following technical scheme: The high-toughness XLPE overhead insulated cable comprises a cable core and an insulating layer, wherein the insulating layer is prepared from the following raw materials, by weight, 50-60 parts of low-density polyethylene, 15-25 parts of linear low-density polyethylene, 15-25 parts of high-density polyethylene, 8-12 parts of modified nano inorganic filler, 6-14 parts of double-end vinyl silicone oil, 8-12 parts of initiator, 0.5-1 part of light stabilizer, 0.1-1 part of antioxidant and 0.2-1 part of lubricant; the modified nano inorganic filler is prepared by modifying nano inorganic filler through a silane coupling agent. By adopting the technical scheme, the low-density polyethylene, the linear low-density polyethylene and the high-density polyethylene are blended to serve as a matrix to form the framework of the insulating material, the low-density polyethylene can provide excellent processing fluidity, the linear low-density polyethylene can improve the tear resistance and the puncture resistance of the material, the high-density polyethylene can improve the rigidity and the strength of the material, and the three materials can be blended to balance the processability, the toughness and the strength. The nano inorganic filler is modified, so that the dispersion uniformity of the nano inorganic filler can be improved, and when the material is impacted and stretched, the energy dissipation effects such as silver streak, shearing and the like can be induced, so that crack growth is effectively prevented, and the toughness and impact strength of the material are remarkably improved. The addition of double-ended vinyl silicone oils is a key point of the present application, which acts as a dual function of the crosslinked network tuning and flexible phase. Firstly, in the crosslinking reaction of an initiator, vinyl groups at two ends of double-end vinyl silicone oil participate in the reaction, but a long flexible siloxane main chain (-Si-O-Si-) of the double-end vinyl silicone oil has extremely large motion freedom degree (high chain flexibility) in a polyethylene matrix, which is equivalent to adding an internal plasticizing section into a compact polyethylene crosslinking network, so that the overall density of the crosslinking network can be effectively reduced, brittleness caused by too dense local crosslinking points is avoided, and the material can still keep relatively good flexibility and elasticity after crosslinking. And the silicone oil molecules themselves constitute a flexible phase dispersed in the polyethylene matrix. When the material is stressed, the flexible micro-regions can absorb and disperse energy through self deformation, so that the toughness of the material is further improved. The application realizes the common guarantee of toughness and strength of the crosslinked polyethylene insulating material mainly through the dual synergistic toughening effect of nano inorganic filler, crosslinked network density adjustment and flexible phase. Preferably, the viscosity of the double-ended vinyl si