Search

CN-121991590-A - Double-layer sintering epoxy powder for offshore tubular piles and preparation method thereof

CN121991590ACN 121991590 ACN121991590 ACN 121991590ACN-121991590-A

Abstract

The invention discloses double-layer sintering epoxy powder for an offshore tubular pile and a preparation method thereof, belongs to the technical field of epoxy powder coating, and is used for solving the technical problem that the solid content, impact resistance, corrosion resistance and ageing resistance of sintering epoxy powder applied to the offshore tubular pile in the prior art are required to be further improved. The marine tubular pile double-layer sintering epoxy powder comprises bottom layer sintering powder and surface layer sintering powder, wherein the bottom layer sintering powder comprises, by weight, 28-32 parts of anti-corrosion epoxy polyester, 68-72 parts of anti-corrosion filler, 0.6-0.8 part of light stabilizer and 2-3 parts of auxiliary additive. According to the invention, the anti-corrosion epoxy polyester, the anti-corrosion filler and other materials are matched with each other to prepare the bottom sintering powder with high anti-corrosion filler content, and the surface sintering powder and the bottom sintering layer are matched with each other, so that the ultraviolet aging resistance, seawater soaking resistance, salt spray resistance and impact retention performance of the coating are effectively improved.

Inventors

  • PAN JIANLIANG
  • Pan Xutao
  • WANG XIAOQIANG
  • WEI QIANCHENG

Assignees

  • 江苏华光控股集团有限公司

Dates

Publication Date
20260508
Application Date
20260116

Claims (10)

  1. 1. The double-layer fusion-bonded epoxy powder for the offshore tubular pile comprises bottom-layer fusion-bonded powder and surface-layer fusion-bonded powder, and is characterized in that the bottom-layer fusion-bonded powder comprises, by weight, 28-32 parts of anti-corrosion epoxy polyester, 68-72 parts of anti-corrosion filler, 0.6-0.8 part of light stabilizer and 2-3 parts of auxiliary additive; The surface layer sintering powder comprises, by weight, 20-30 parts of anti-corrosion epoxy polyester, 32-38 parts of anti-corrosion filler, 50-60 parts of fluorocarbon resin, 0.6-0.8 part of light stabilizer and 2-3 parts of additive; Wherein the light stabilizer is 4-aminomethyl-2, 6-tetramethylpiperidine.
  2. 2. The double-layer sintered epoxy powder for the marine pipe pile according to claim 1, wherein the anti-corrosion epoxy polyester is obtained by processing the following steps: A1, mixing and stirring 1,3, 5-trialdehyde-1, 3, 5-triazine, 2, 5-diaminobenzyl alcohol and N, N-dimethylformamide, heating a reaction system to 135-145 ℃, carrying out heat preservation reaction for 4-5h, cooling the reaction system to 100-110 ℃, adding epichlorohydrin and sodium hydroxide solution into the reaction system, carrying out heat preservation reaction for 6-8h, and carrying out aftertreatment to obtain triazine modified epoxy resin; a2, heating the triazine modified epoxy resin to 120-130 ℃, stirring until the system is melted, adding amino-terminated polysiloxane into the reaction system, carrying out heat preservation reaction for 60-80min, and discharging while the reaction system is hot to obtain the anti-corrosion epoxy polyester.
  3. 3. The double-layer sintered epoxy powder for offshore pipe piles according to claim 2, wherein in the step A1, the 1,3, 5-trialdehyde-1, 3, 5-triazine, 2, 5-diamino benzyl alcohol, N-dimethylformamide, epichlorohydrin and sodium hydroxide solution are used in a ratio of 1g to 1.5g to 5-6mL to 4-5mL to 2-3mL, the concentration of the sodium hydroxide solution is 10-12mol/L, and in the step A2, the weight ratio of the triazine modified epoxy resin to the amino-terminated polysiloxane is 7:2.8-3.2.
  4. 4. The double-layer sintered epoxy powder for the offshore tubular pile, which is characterized in that the preparation method of the amino-terminated polysiloxane is characterized in that octamethyl cyclotetrasiloxane, trifluoropropyl methyl cyclotrisiloxane and sulfuric acid are mixed and stirred, the temperature of a reaction system is raised to 85-95 ℃, the reaction is kept for 40-50min, 1, 3-bis (2-aminoethylaminomethyl) tetramethyl disiloxane is added into the reaction system, the reaction is kept for 30-50min, and the amino-terminated polysiloxane with the molecular weight of more than 1000Da is obtained after post treatment.
  5. 5. The marine pipe pile double-layer sintered epoxy powder according to claim 4, wherein the dosage ratio of octamethyl cyclotetrasiloxane, trifluoropropyl methyl cyclotrisiloxane, sulfuric acid and 1, 3-bis (2-aminoethylaminomethyl) tetramethyl disiloxane is 15g:7-8g:3-4mL:2-3g, and the mass fraction of sulfuric acid is 70-80%.
  6. 6. The double-layer sintered epoxy powder for the marine pipe pile according to claim 1, wherein the anti-corrosion filler is obtained by processing the following steps: B1, mixing and stirring aluminum chloride, zinc chloride, magnesium chloride, sodium dodecyl sulfate and deionized water until the system is dissolved, adding a sodium phosphate solution into a reaction system, adjusting the pH value of the system to be 7-8, standing and aging for 3-5 hours, and performing aftertreatment to obtain coprecipitated phosphate; And B2, mixing coprecipitated phosphate, zinc oxide loaded montmorillonite and Tris buffer solution, performing ultrasonic dispersion for 30-50min, adding dopamine hydrochloride into a reaction system at room temperature, performing heat preservation reaction for 10-12h, and performing post-treatment to obtain the anti-corrosion filler.
  7. 7. The double-layer fusion-bonded epoxy powder for the marine tubular pile according to claim 6, wherein in the step B1, the dosage ratio of aluminum chloride to zinc chloride to magnesium chloride to sodium dodecyl sulfate to deionized water is 3-5g to 6-7g to 1.5g to 150mL, the sodium phosphate solution consists of sodium phosphate to deionized water according to 1g to 2mL, and in the step B2, the dosage ratio of coprecipitated phosphate to zinc oxide loaded montmorillonite to Tris buffer to dopamine hydrochloride is 3-4g to 5-6g to 50mL to 0.6-0.8g, and the concentration of the Tris buffer is 0.1mol/L and pH=8.5.
  8. 8. The preparation method of the double-layer sintered epoxy powder for the offshore tubular pile is characterized in that zinc chloride and deionized water are mixed and stirred until the system is dissolved, montmorillonite is added into a reaction system, ultrasonic dispersion is carried out for 30-50min at room temperature, sodium hydroxide solution is added into the reaction system, the pH value of the system is regulated to be 8-9, and the zinc oxide loaded montmorillonite is obtained after post treatment.
  9. 9. The double-layer sintered epoxy powder for the offshore tubular pile, which is disclosed in claim 8, wherein the dosage ratio of zinc chloride, deionized water and montmorillonite is 3-4g to 20mL to 8g, and the concentration of the sodium hydroxide solution is 2-3mol/L.
  10. 10. A method for preparing the double-layer sintered epoxy powder of the marine pipe pile according to any one of claims 1 to 9, which is characterized by comprising the following steps: s1, preparing bottom layer sintering powder, namely mixing anti-corrosion epoxy polyester, anti-corrosion filler, light stabilizer and auxiliary additive, ball milling, and sieving with a 100-mesh sieve to obtain bottom layer sintering powder; s2, preparing surface layer sintering powder, namely mixing the anti-corrosion epoxy polyester, the anti-corrosion filler, the fluorocarbon resin, the light stabilizer and the additive, ball milling, and sieving with a 100-mesh sieve to obtain the surface layer sintering powder.

Description

Double-layer sintering epoxy powder for offshore tubular piles and preparation method thereof Technical Field The invention relates to the technical field of epoxy powder coating, in particular to double-layer sintering epoxy powder for an offshore tubular pile and a preparation method thereof. Background In marine engineering such as offshore wind power, cross-sea bridges and harbor industrial heads, steel pipe piles are used as basic bearing members in a large number. The pipe pile is in complex service environments such as a marine atmosphere area, a splash area, a tidal range area, a full immersion area and the like for a long time, is subjected to multi-factor coupling effects such as Cl - permeation, dissolved oxygen action, tide dry-wet alternation, sea wave scouring and sediment abrasion, microorganism adhesion, ultraviolet irradiation, temperature circulation and the like, is extremely easy to generate electrochemical corrosion and is accompanied with the failure phenomena such as foaming, cracking, spalling and the like of a coating, and once a protection system fails, the wall thickness of the pipe pile is reduced, the bearing capacity is reduced, and high shutdown maintenance cost and safety risk are brought. The protective coating systems for steel structures in the prior art are more, and comprise a single-layer or multi-layer epoxy system, a sintered epoxy powder coating, a polyethylene/polypropylene outer sheath composite system, polyurethane, a modified coating and the like. The fusion-bonded epoxy powder is widely applied to the protection of pipelines and marine steel members due to high construction efficiency, better compactness and adhesion and excellent chemical medium resistance, an epoxy matrix is easy to pulverize under the conditions of ultraviolet and hot oxygen and generate microcracks, so that shielding property is reduced, medium permeation is accelerated, in long-term wet and hot circulation of a splashing region and a tidal range region, moisture and chloride ions are easy to diffuse along coating defects and interfaces, so that wet adhesion is reduced, foaming and interface stripping are caused, and meanwhile, local damage is caused by sea wave impact, floater impact and transportation construction collision, and the traditional epoxy system has insufficient toughness, easily expanded cracks and further shortened service life. In order to improve corrosion resistance, shielding and passivation effects are usually enhanced by increasing the consumption of inorganic anti-corrosion fillers in engineering, but the increase of the consumption of the fillers can obviously increase the viscosity of a system, reduce the melt flow and leveling capability, lead to the formation of pores, pinholes and agglomeration defects in the powder sintering and curing process, lead to poor interfacial compatibility of common inorganic fillers and organic resins, lead to easy interfacial debonding and stress concentration, lead to film embrittlement and impact resistance reduction, and lead to difficult preparation of thick film anti-corrosion coatings with high filler content, compactness and good toughness. In view of the technical drawbacks of this aspect, a solution is now proposed. Disclosure of Invention The invention aims to provide double-layer sintering epoxy powder for an offshore tubular pile and a preparation method thereof, which are used for solving the technical problem that the filler content, impact resistance, corrosion resistance and ageing resistance of sintering epoxy powder applied to the offshore tubular pile in the prior art are required to be further improved. The aim of the invention can be achieved by the following technical scheme: The double-layer fusion-bonded epoxy powder for the marine tubular pile comprises a bottom layer fusion-bonded powder and a surface layer fusion-bonded powder, wherein the bottom layer fusion-bonded powder comprises, by weight, 28-32 parts of anti-corrosion epoxy polyester, 68-72 parts of anti-corrosion filler, 0.6-0.8 part of light stabilizer and 2-3 parts of auxiliary additive; The surface layer sintering powder comprises, by weight, 20-30 parts of anti-corrosion epoxy polyester, 32-38 parts of anti-corrosion filler, 50-60 parts of fluorocarbon resin, 0.6-0.8 part of light stabilizer and 2-3 parts of additive; Wherein the light stabilizer is 4-aminomethyl-2, 6-tetramethylpiperidine. Further, the anti-corrosion epoxy polyester is obtained by processing the following steps: A1, mixing and stirring 1,3, 5-trialdehyde-1, 3, 5-triazine, 2, 5-diaminobenzyl alcohol and N, N-dimethylformamide, heating a reaction system to 135-145 ℃, carrying out heat preservation reaction for 4-5h, cooling the reaction system to 100-110 ℃, adding epichlorohydrin and sodium hydroxide solution into the reaction system, carrying out heat preservation reaction for 6-8h, and carrying out aftertreatment to obtain triazine modified epoxy resin; The synthetic reaction for