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CN-121975409-A - Fluorine-free environment-friendly type pollution-resistant anti-skid sand grain powder coating and preparation method thereof

CN121975409ACN 121975409 ACN121975409 ACN 121975409ACN-121975409-A

Abstract

The invention relates to the technical field of powder coatings, in particular to a fluorine-free environment-friendly type pollution-resistant anti-skid sand grain powder coating and a preparation method thereof. The powder coating is composed of carboxyl-terminated polyester resin, bisphenol A epoxy resin, modified nano zinc oxide, polyethylene micro wax powder, PDMS coated silicon dioxide and other raw materials, wherein the carboxyl-terminated polyester resin can undergo a grafting reaction with active groups on the modified nano zinc oxide in the preparation process, so that the dispersibility of nanoparticles is improved, when the coating is cured, the carboxyl-terminated polyester resin can also undergo cross-linking with the bisphenol A epoxy resin to form a compact three-dimensional network structure, and meanwhile, a polydimethylsiloxane chain segment is introduced into the resin, and the modified nano zinc oxide with the surface grafted indole quaternary ammonium salt is used, so that the coating has both low surface energy characteristics and spectrum antibacterial capability. The powder coating integrates the advantages of fluoride-free environment protection, pollution resistance, skid resistance, antibiosis and excellent mechanical property, and solves the technical problem of poor function cooperativity of the traditional sand grain coating.

Inventors

  • YANG QINGWEI
  • LIU JUN
  • JI HUABIN
  • Shangguan jin

Assignees

  • 浙江超浪新材料有限公司

Dates

Publication Date
20260505
Application Date
20260403

Claims (10)

  1. 1. The fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating is characterized by comprising, by weight, 30-40 parts of carboxyl-terminated polyester resin, 20-30 parts of bisphenol A epoxy resin, 1.5-2.5 parts of modified nano zinc oxide, 2-4 parts of polyethylene micro wax powder, 0.8-1.5 parts of flatting agent, 1-2 parts of PDMS coated silica, 0.5-0.8 part of light stabilizer and 0.1-0.3 part of curing accelerator; The carboxyl-terminated polyester resin is branched carboxyl-terminated polyester containing dimethyl siloxane chain segments; The modified nano zinc oxide is nano zinc oxide grafted through a Si-O-Zn covalent bond and containing indole quaternary ammonium salt and hydrophilic sulfonic group.
  2. 2. The fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating is characterized in that the leveling agent is one of polyacrylate leveling agent or organosilicon-acrylate leveling agent, the light stabilizer is a mixture of hindered amine light stabilizer and ultraviolet absorbent according to a weight ratio of 1:1, and the curing accelerator is 2-methylimidazole.
  3. 3. The fluorine-free environment-friendly stain-resistant anti-slip sand grain powder coating as claimed in claim 1, wherein the preparation method of the carboxyl-terminated polyester resin is as follows: Adding adipic acid, neopentyl glycol, polydimethylsiloxane dihydric alcohol, tridecanedioic acid, 1, 4-cyclohexanedimethanol and trimethylolpropane into a reaction kettle provided with a water separator, heating to 180-200 ℃ under the protection of nitrogen, stirring, reacting for 2-3h, continuously heating to 220-240 ℃, gradually vacuumizing to less than or equal to 50Pa, reacting for 2.5-3.5h, cooling to 180 ℃ after the reaction is finished, introducing nitrogen into the reaction kettle to break vacuum, discharging molten resin, naturally cooling to room temperature, and crushing to the particle size of less than or equal to 5mm by a crusher to obtain carboxyl-terminated polyester resin.
  4. 4. The fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating as claimed in claim 3, wherein the carboxyl terminated polyester resin is prepared from adipic acid, neopentyl glycol, polydimethylsiloxane dihydric alcohol, tridecanedioic acid, 1, 4-cyclohexanedimethanol and trimethylolpropane according to a molar ratio of 1-1.2:0.6-0.8:0.2-0.3:0.4-0.6:0.3-0.4:0.1-0.2, and the polydimethylsiloxane dihydric alcohol has a number average molecular weight of 1500.
  5. 5. The fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating as claimed in claim 1, wherein the preparation method of the modified nano zinc oxide is as follows: (1) Adding 2, 3-trimethyl-3H-indole-5-carboxylic acid and 1, 3-propane sultone into anhydrous 1, 4-dioxane, heating to 80-100 ℃ under the protection of nitrogen, stirring for reaction for 3-5H, cooling to room temperature after the reaction is finished, adding diethyl ether, filtering and collecting the obtained solid, washing with ethyl acetate for 3 times, and drying to obtain an intermediate A; (2) Adding the intermediate A into anhydrous 1, 4-dioxane, stirring and dissolving, adding gamma-glycidoxypropyl trimethoxy silane, heating to 70-80 ℃ under the protection of nitrogen, stirring and reacting for 2-4h, and distilling under reduced pressure to remove the solvent after the reaction is finished to obtain an intermediate B; (3) Adding nano zinc oxide into ethanol, performing ultrasonic dispersion for 10-20min, adjusting pH to 5-6 with dilute hydrochloric acid, adding an intermediate B, heating to 70-80 ℃, stirring for reaction for 2-3h, filtering to collect solid precipitate after the reaction is finished, washing, and drying to obtain the modified nano zinc oxide.
  6. 6. The fluorine-free environment-friendly stain-resistant anti-slip sand grain powder coating material according to claim 5, wherein the molar ratio of 2, 3-trimethyl-3H-indole-5-carboxylic acid to 1, 3-propane sultone in (1) is 1:1-1.2, and the weight ratio of 2, 3-trimethyl-3H-indole-5-carboxylic acid, anhydrous 1, 4-dioxane and diethyl ether is 1:8-12:10-20.
  7. 7. The fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating is characterized in that the molar ratio of the intermediate A to the gamma-glycidoxypropyl trimethoxysilane in the step (2) is 1:1-1.2, and the weight ratio of the intermediate A to the anhydrous 1, 4-dioxane is 1:8-12.
  8. 8. The fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating is characterized in that the weight ratio of nano zinc oxide to ethanol to the intermediate B in the step (3) is 1:8-12:0.12-0.2, and the concentration of dilute hydrochloric acid is 0.1-0.5mol/L.
  9. 9. The method for preparing the fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating according to any one of claims 1 to 8, which is characterized by comprising the following steps: S1, mixing carboxyl-terminated polyester resin, bisphenol A epoxy resin, modified nano zinc oxide, polyethylene micro wax powder, a leveling agent, PDMS coated silica, a light stabilizer and a curing accelerator, and stirring at a high speed of 1000-1500rpm for 10-20min to obtain a premixed material; s2, adding the premixed material into a double-screw extruder, and performing melt extrusion to obtain uniform melt material strips; S3, cooling the molten material strips to room temperature through a cooling conveyor belt, and conveying the molten material strips into a pulverizer to pulverize the molten material strips to a particle size of 30-50 mu m to obtain pulverized materials; s4, sieving the crushed materials through a 180-200-mesh stainless steel screen to remove coarse particles, and obtaining the fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating.
  10. 10. The method for preparing the fluorine-free environment-friendly type pollution-resistant anti-skid sand grain powder coating according to claim 9, wherein the temperature of a first area of the double-screw extruder in the step S2 is 95-105 ℃, the temperature of a second area is 105-115 ℃, the temperature of a third area is 115-125 ℃, the temperature of a machine head is 115-125 ℃, and the rotating speed of a screw is 30-50rpm.

Description

Fluorine-free environment-friendly type pollution-resistant anti-skid sand grain powder coating and preparation method thereof Technical Field The invention relates to the technical field of powder coatings, in particular to a fluorine-free environment-friendly type pollution-resistant anti-skid sand grain powder coating and a preparation method thereof. Background Along with the increasing strictness of environmental protection regulations and the improvement of the requirements of consumers on the functional diversity of the paint, the powder paint has wider application in the fields of building decoration, household articles, industrial equipment and the like due to the advantages of no emission of Volatile Organic Compounds (VOC) and high resource utilization rate. The sand grain powder coating is widely applied to scenes such as floors, stair handrails, kitchen and bathroom appliances and the like which need to be compatible with practicality and attractiveness by virtue of the characteristics of unique rough texture, good anti-skid effect and fine flaw concealment of the surface, and the market demand is continuously growing. However, many technical pain points still exist in the existing sand grain powder coating to be solved. In the aspect of environmental protection, the traditional sand grain coating is mostly dependent on adding fluorine-containing compounds to realize excellent hydrophobic and stain-resistant performances, the substances have bioaccumulation property, are easy to cause potential harm to ecological environment and human health, do not accord with the current development trend of fluorine-free environment protection, and partial fluorine-free sand grain coating is lack of high-efficiency hydrophobic components, so that the stain-resistant performances are greatly reduced, and stains such as greasy dirt, fruit juice and the like are easy to adhere and difficult to clean. In the aspect of core function coordination, the existing product is difficult to simultaneously consider the anti-skid, anti-fouling and antibacterial properties. The anti-skid effect of most sand grain paint is only dependent on a surface physical coarse structure, friction coefficient suddenly drops easily due to water film lubrication in a wet environment, anti-skid stability is poor, stain resistance is limited by compatibility of resin and filler, coating compactness is insufficient, liquid stains are easy to permeate and remain, meanwhile, aiming at the antibacterial requirements of special scenes such as hospitals, food processing workshops and the like, the existing sand grain paint is mostly realized by additionally adding an antibacterial agent, but the compatibility of the antibacterial agent and a paint system is poor, aggregation and precipitation are easy to occur, the antibacterial effect is short, temporary and uneven, and long-term stable broad-spectrum antibacterial cannot be realized. In terms of structural stability and appearance texture, sand grain morphology regulation of the existing sand grain coating is mostly dependent on single wax powder or filler, the problems of uneven sand grain thickness, particle aggregation and the like are prone to occurring, appearance consistency is affected, the cross-linking structure of a resin system is unreasonable in design, the mechanical property of a coating is poor, the impact resistance and bending resistance are weak, the coating is prone to cracking and falling after long-term use, in addition, the dispersibility of nano filler in the coating is poor, the functional characteristics of the nano filler cannot be fully exerted, the weather resistance of the coating can be further affected, the coating is prone to light and color losing during outdoor use, and the service life is shortened. Therefore, development of the sand grain powder coating which is fluorine-free, environment-friendly, high-efficiency, anti-slip, durable, stain-resistant and wide-spectrum antibacterial functions, uniform and fine in sand grain form, excellent in mechanical property and weather resistance becomes a technical problem to be solved urgently in the current industry, and has important significance in expanding the application scene of the powder coating and meeting the high-end market demand. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a fluorine-free environment-friendly type pollution-resistant anti-skid sand grain powder coating and a preparation method thereof. Based on the purposes, the invention provides a fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating and a preparation method thereof, wherein the fluorine-free environment-friendly stain-resistant anti-skid sand grain powder coating comprises, by weight, 30-40 parts of carboxyl-terminated polyester resin, 20-30 parts of bisphenol A epoxy resin, 1.5-2.5 parts of modified nano zinc oxide, 2-4 parts of polyethylene micro wax p