Search

CN-122011624-A - MPP power cable protection tube and preparation process thereof

CN122011624ACN 122011624 ACN122011624 ACN 122011624ACN-122011624-A

Abstract

The invention relates to the technical field of polymer composite materials, and discloses an MPP power cable protection tube which is prepared from the following raw materials, by weight, 100 parts of polyvinyl chloride resin, 15-30 parts of an ethylene-vinyl acetate copolymer, 5-15 parts of pre-crosslinked organosilicon microspheres, 20-40 parts of a composite inorganic filler, 0.5-2 parts of a silane coupling agent, 2-5 parts of a heat stabilizer, 1-3 parts of a lubricant and 3-8 parts of a flame retardant. The rigid matrix-elastic phase-organosilicon microsphere multiphase synergistic toughening reinforcing system is constructed by taking polyvinyl chloride resin as a main body and matching with ethylene-vinyl acetate copolymer and pre-crosslinked organosilicon microsphere with specific content, and the pre-crosslinked organosilicon microsphere is taken as a second phase elastic particle, so that silver streaks and shearing bands can be effectively initiated, crack propagation is prevented, the impact toughness and low-temperature performance of the material are obviously improved, and the interface combination is further enhanced by matching with the composite inorganic filler subjected to surface treatment of a silane coupling agent, and the rigidity, the wear resistance and the thermal stability are improved.

Inventors

  • YAO HUILIANG
  • WANG AQING
  • WANG XUZHONG

Assignees

  • 山东海川电力器材有限公司

Dates

Publication Date
20260512
Application Date
20260317

Claims (10)

  1. 1. The MPP power cable protection pipe is characterized by being prepared from the following raw materials in parts by weight: 100 parts of polyvinyl chloride resin; 15-30 parts of ethylene-vinyl acetate copolymer; 5-15 parts of pre-crosslinked organosilicon microspheres; 20-40 parts of composite inorganic filler; 0.5-2 parts of silane coupling agent; 2-5 parts of a heat stabilizer; 1-3 parts of a lubricant; 3-8 parts of flame retardant; Wherein the pre-crosslinked organosilicon microsphere is prepared from vinyl silicone oil and hydrogen-containing silicone oil under the action of a platinum catalyst by emulsion crosslinking, the average grain diameter is 1-10 mu m, and the composite inorganic filler is composed of silicon nitride, modified mica powder and white carbon black according to the weight ratio of (1-3) (2-5) (1-2).
  2. 2. The MPP power cable protection tube of claim 1, wherein the ethylene-vinyl acetate copolymer has a vinyl acetate mass content of 18-28% and a melt flow rate of 3-10g/10min.
  3. 3. The MPP power cable protection tube as claimed in claim 1, wherein in the pre-crosslinked organosilicon microspheres, the mass ratio of vinyl silicone oil to hydrogen-containing silicone oil is (5-8) 1, the viscosity of the vinyl silicone oil is 10000-50000 mPa.s, the molar content of vinyl is 1.5-3.0%, the viscosity of the hydrogen-containing silicone oil is 20-50mm2/s, the active hydrogen content is 0.8-1.5%, the emulsifier adopted by the emulsion crosslinking method is a nonionic surfactant, the reaction temperature is 60-80 ℃, and the reaction time is 2-4 hours.
  4. 4. The MPP power cable protection tube of claim 1, wherein the modified mica powder is a flaky mica surface-treated with a silane coupling agent, and the particle size D50 is 800-1500 mesh.
  5. 5. The MPP power cable protection tube of claim 1, wherein the silane coupling agent is at least one of gamma-aminopropyl triethoxysilane, gamma-glycidoxypropyl trimethoxysilane.
  6. 6. The MPP power cable protection tube of claim 1, wherein the heat stabilizer is a calcium zinc composite stabilizer, the lubricant is polyethylene wax or oxidized polyethylene wax, and the flame retardant is at least one of ammonium polyphosphate and melamine cyanurate.
  7. 7. A process for preparing an MPP power cable protection tube according to any one of claims 1 to 6, comprising the steps of: S1, preparing pre-crosslinked organic silicon microspheres, namely mixing vinyl silicone oil, hydrogen-containing silicone oil, an emulsifier and water, forming stable emulsion by high-speed shearing and emulsification, adding a platinum catalyst, reacting for 2-4 hours at 60-80 ℃, washing and drying to obtain the pre-crosslinked organic silicon microspheres; s2, pretreatment of the filler, namely mixing silicon nitride, modified mica powder, white carbon black and a silane coupling agent in a high-speed mixer at 90-110 ℃ for 5-15 minutes to obtain a surface-treated composite inorganic filler; s3, high-speed heat mixing, namely adding polyvinyl chloride resin and ethylene-vinyl acetate copolymer into a high-speed mixer, heating to 90-110 ℃, sequentially adding the pre-crosslinked organosilicon microspheres prepared in the step S1, the surface-treated composite inorganic filler, heat stabilizer, lubricant and flame retardant prepared in the step S2, and continuously mixing at the rotating speed of 800-1200 r/min until the material temperature reaches 115-125 ℃ to obtain uniform premix; S4, melt extrusion and molding, namely feeding the premix into a double-screw extruder, melting, plasticizing, extruding and granulating in a processing temperature range of 150-190 ℃ to obtain master batches, feeding the master batches into a pipe extruder, extruding, shaping, cooling, drawing and cutting under the die temperature of 175-185 ℃ and the vacuum shaping pressure of minus 0.06-minus 0.08MPa to obtain the MPP power cable protective pipe.
  8. 8. The process according to claim 7, wherein the total mixing time of the high-speed thermal mixing in step S3 is 8 to 15 minutes.
  9. 9. The process according to claim 7, wherein the specific processing temperature of the twin-screw extruder in the step S4 is set to 150-160 ℃, 160-170 ℃, 170-180 ℃, 175-185 ℃ in the first zone, 180-190 ℃ in the third zone, and 180-185 ℃ in the fourth zone.
  10. 10. The process according to claim 7, wherein the screw speed of the pipe extruder in step S4 is 15-25rpm.

Description

MPP power cable protection tube and preparation process thereof Technical Field The invention relates to the technical field of polymer composite materials, in particular to an MPP power cable protection tube and a preparation process thereof. Background The power cable protection tube is widely applied to the laying and protection of cables in power engineering, and is required to have good mechanical strength, impact resistance, wear resistance, flame retardance and low temperature resistance, and at present, the common cable protection tube mostly adopts polyvinyl chloride (PVC) as basic resin, and the comprehensive performance of the common cable protection tube is improved by adding various modifiers and fillers. For example, chinese patent application CN111363271a discloses a corrosion-resistant MPP power cable protection tube material, which is compounded by using polyvinyl chloride resin and propylene-ethylene random copolymer, fluorosilicone rubber and other components, and is added with a large amount of nano-filler and reinforcing fiber, and the scheme has a certain improvement in strength, high temperature resistance and wear resistance, but still has the following obvious disadvantages: 1. The composition is complex, the cost is high, the scheme uses more than ten raw materials including various rubbers, various nano fillers and fibers, the formula system is complex, the raw material cost is high, the compatibility and the dispersibility among the components are difficult to ensure, and the material performance is easy to be unstable. 2. The process is complicated, the energy consumption is high, the preparation process is required to be subjected to multi-step processes such as low-speed stirring, high-temperature mixing, normal-temperature high-speed stirring and the like, the mixing temperature is up to 160-180 ℃, the high-speed stirring time is up to 18-22 minutes, and the whole process is high in energy consumption, low in efficiency and unfavorable for large-scale production. 3. The toughness is improved only limited, and the low-temperature brittleness is improved, namely, although the toughening components such as the fluorosilicone rubber are added, the notch impact strength and the low-temperature embrittlement temperature of the material are still not ideal due to the lack of effective interface compatibility design and elastomer network construction, and brittle fracture is easy to occur in cold areas or under impact working conditions. Disclosure of Invention The invention aims to provide an MPP power cable protection tube and a preparation process thereof, which are used for solving the problems in the background technology. In order to achieve the purpose, the invention provides the technical scheme that the MPP power cable protection tube is prepared from the following raw materials in parts by weight: 100 parts of polyvinyl chloride resin; 15-30 parts of ethylene-vinyl acetate copolymer; 5-15 parts of pre-crosslinked organosilicon microspheres; 20-40 parts of composite inorganic filler; 0.5-2 parts of silane coupling agent; 2-5 parts of a heat stabilizer; 1-3 parts of a lubricant; 3-8 parts of flame retardant; Wherein the pre-crosslinked organosilicon microsphere is prepared from vinyl silicone oil and hydrogen-containing silicone oil under the action of a platinum catalyst by emulsion crosslinking, the average grain diameter is 1-10 mu m, and the composite inorganic filler is composed of silicon nitride, modified mica powder and white carbon black according to the weight ratio of (1-3) (2-5) (1-2). As a preferable technical scheme of the invention, the mass content of vinyl acetate in the ethylene-vinyl acetate copolymer is 18-28%, and the melt flow rate is 3-10g/10min. As a preferable technical scheme of the invention, in the pre-crosslinked organosilicon microsphere, the mass ratio of vinyl silicone oil to hydrogen-containing silicone oil is (5-8) 1, the viscosity of the vinyl silicone oil is 10000-50000 mPa.s, the vinyl molar content is 1.5-3.0%, the viscosity of the hydrogen-containing silicone oil is 20-50mm < 2 >/s, the active hydrogen content is 0.8-1.5%, the emulsifier adopted by the emulsion crosslinking method is a nonionic surfactant, the reaction temperature is 60-80 ℃, and the reaction time is 2-4 hours. As a preferable technical scheme of the invention, the modified mica powder is flaky mica subjected to surface treatment by a silane coupling agent, and the particle size D50 is 800-1500 meshes. As a preferable technical scheme of the invention, the silane coupling agent is at least one of gamma-aminopropyl triethoxysilane and gamma-glycidol ether oxypropyl trimethoxysilane. As a preferable technical scheme of the invention, the heat stabilizer is a calcium-zinc composite stabilizer, the lubricant is polyethylene wax or oxidized polyethylene wax, and the flame retardant is at least one of ammonium polyphosphate and melamine cyanurate. A process for preparing the M