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CN-121045702-B - Rigid polyvinyl chloride pipe and preparation method thereof

CN121045702BCN 121045702 BCN121045702 BCN 121045702BCN-121045702-B

Abstract

The invention discloses a rigid polyvinyl chloride pipe and a preparation method thereof, and relates to the technical field of materials. The hard polyvinyl chloride pipe comprises, by weight, 80-90 parts of ultra-high polymerization degree polyvinyl chloride, 10-20 parts of ultra-low polymerization degree polyvinyl chloride, 2-4 parts of nano boehmite, 4-5 parts of a stabilizer, 8-12 parts of a plasticizer, 0.6-1.2 parts of a lubricant, 15-25 parts of a filler, 3-5 parts of core titanium white, wherein the polymerization degree of the ultra-high polymerization degree polyvinyl chloride is 1500-1800, and the polymerization degree of the ultra-low polymerization degree polyvinyl chloride is 600-800. The rigid polyvinyl chloride pipe has excellent processability, thermal stability, impact resistance, flame retardance, insulating property and surface glossiness.

Inventors

  • LI ZHUO
  • LI MING
  • ZHANG FANG
  • HUANG BIN
  • TANG YONGHUI
  • Pan Quhua
  • YANG SHANGBAO

Assignees

  • 佛山建发瑞通科技有限公司

Dates

Publication Date
20260508
Application Date
20250909

Claims (10)

  1. 1. The hard polyvinyl chloride pipe is characterized by comprising the following raw material components in parts by weight: 80-90 parts of ultra-high polymerization degree polyvinyl chloride, 10-20 parts of ultra-low polymerization degree polyvinyl chloride, 2-4 parts of nano boehmite, 4-5 parts of stabilizer, 8-12 parts of plasticizer, 0.6-1.2 parts of lubricant, 15-25 parts of filler and 3-5 parts of nuclear titanium white; The polymerization degree of the ultra-high polymerization degree polyvinyl chloride is 1500-1800, and the polymerization degree of the ultra-low polymerization degree polyvinyl chloride is 600-800; the nuclear titanium white is made of Jianfu Ruitong and has the model of RTR-201.
  2. 2. The rigid polyvinyl chloride pipe according to claim 1, wherein the ultra-high degree of polymerization polyvinyl chloride has a degree of polymerization of 1700 and the ultra-low degree of polymerization polyvinyl chloride has a degree of polymerization of 700.
  3. 3. The hard polyvinyl chloride pipe according to claim 1, wherein the average particle size of the nano-boehmite is 30 to 60 nm and/or the average particle size of the core titanium white is 500 to 550 nm.
  4. 4. The rigid polyvinyl chloride pipe according to claim 1, wherein the stabilizer is a calcium zinc stabilizer, and the mass ratio of Ca to Zn in the calcium zinc stabilizer is 2:1.
  5. 5. The rigid polyvinyl chloride pipe according to claim 1, wherein the plasticizer is epoxidized soybean oil having an epoxy value of 6 to 8%.
  6. 6. The rigid polyvinyl chloride pipe according to claim 1, wherein the lubricant comprises at least one of oxidized polyethylene wax, calcium stearate, zinc stearate, glycerol monostearate, pentaerythritol ester.
  7. 7. The rigid polyvinyl chloride pipe according to claim 1, wherein the filler comprises at least one of heavy calcium carbonate, nano calcium, talc, kaolin, and barium sulfate.
  8. 8. The rigid polyvinyl chloride pipe according to claim 1, wherein the filler has a particle size of 800-1500 mesh.
  9. 9. A process for producing a rigid polyvinyl chloride pipe according to any one of claims 1 to 8, wherein the components are uniformly mixed and then melt-extruded in an extruder to obtain the rigid polyvinyl chloride pipe.
  10. 10. The process for preparing a rigid polyvinyl chloride pipe according to claim 9 wherein the extruder has parameters of 145 to 150℃for the feed section, 160 to 165℃for the compression section, 170 to 175℃for the metering section, 180 to 185℃for the die head, 25 to 30 rpm for the screw speed and 1.5 to 2.0 m/min for the draw speed.

Description

Rigid polyvinyl chloride pipe and preparation method thereof Technical Field The invention relates to the technical field of materials, in particular to a hard polyvinyl chloride pipe and a preparation method thereof. Background The hard polyvinyl chloride (PVC-U) threading pipe has the advantages of excellent insulating property, strong corrosion resistance, convenient construction, lower cost, wide application range and the like, and has obvious cost performance advantage in the conventional civil electrical engineering. The typical PVC conduit production process comprises the steps of mixing PVC resin and auxiliary agent, high-temperature extrusion molding, cooling and shaping, cutting and quality inspection. However, at present, PVC has the following problems in the production process: 1. risk of environmental pollution Vinyl Chloride Monomer (VCM) release PVC has the potential to release VCM, a known carcinogen, when processed at 160-200 ℃ and prolonged exposure to high concentrations of vinyl chloride monomer can increase the risk of cancer. 2. Difficult thermal degradation control The decomposition temperature window is narrow, the PVC resin is rapidly decomposed at 240-260 ℃ and the extrusion temperature needs to be accurately controlled. Yellowing index-conjugated double bonds may be generated during processing, leading to yellowing of the pipe. 3. High equipment loss Screw wear-calcium carbonate filler and pigment auxiliary agent lead to shortened twin screw life. Die orifice accumulation: the machine is required to be stopped for cleaning at intervals, the equipment utilization rate is reduced. Equipment corrosion-PVC decomposes during processing to produce hydrogen chloride (HCl) gas, which is corrosive and may corrode the screw and metal mold. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a rigid polyvinyl chloride pipe and a preparation method thereof. The rigid polyvinyl chloride pipe has excellent processability, thermal stability, impact resistance, flame retardance, insulating property and surface glossiness. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: in a first aspect, the invention provides a hard polyvinyl chloride pipe comprising the following raw material components in parts by weight: 80-90 parts of ultra-high polymerization degree polyvinyl chloride (HPVC), 10-20 parts of ultra-low polymerization degree polyvinyl chloride (LPVC), 2-4 parts of nano boehmite, 4-5 parts of stabilizer, 8-12 parts of plasticizer, 0.6-1.2 parts of lubricant, 15-25 parts of filler and 3-5 parts of nuclear titanium white; The polymerization degree of the ultra-high polymerization degree polyvinyl chloride is 1500-1800, and the polymerization degree of the ultra-low polymerization degree polyvinyl chloride is 600-800. According to the invention, by adding two polyvinyl chloride compounds with different polymerization degrees, the strength of the hard polyvinyl chloride pipe is improved, the processing fluidity is improved, and the hard polyvinyl chloride pipe has excellent impact resistance. The addition of nano boehmite for physically blocking flame is beneficial to improving the flame retardant property and the impact strength of the hard polyvinyl chloride pipe, and can enable the hard polyvinyl chloride pipe to have good surface glossiness. The hardness of the nuclear titanium white is smaller than that of titanium dioxide, so that abrasion of the raw materials to a screw is effectively reduced, meanwhile, the nuclear titanium white also has higher lubricating property, the fluidity of the raw materials can be increased, and the heat energy generation in the production process can be reduced, so that the decomposition of PVC resin is reduced, the emission of harmful substances is reduced, and the yellowing in the processing process is inhibited. Therefore, the components are matched with each other, so that the rigid polyvinyl chloride pipe has excellent processability, thermal stability, impact resistance, flame retardance, insulating property and surface glossiness. Preferably, the polymerization degree of the ultra-high polymerization degree polyvinyl chloride is 1700, and the polymerization degree of the ultra-low polymerization degree polyvinyl chloride is 700. Preferably, the average particle size of the nano-boehmite is from 30 to 60nm, preferably 50nm. Preferably, the average particle size of the core titanium dioxide is 500-550nm, preferably 520nm. Preferably, the stabilizer is a calcium zinc stabilizer, the mass ratio of Ca to Zn is 2:1, and the initial whiteness of the rigid polyvinyl chloride pipe is improved by adding 0.3 part of beta-diketone. Preferably, the plasticizer is Epoxidized Soybean Oil (ESO) having an epoxy value of 6-8% and the plasticizing temperature can be reduced by adding the plasticizer. Preferably, the lubricant comprises at least one of oxidized polyethylene wax, ca