Steel rail radiation heat dissipation coating and preparation method thereof

Abstract

The invention relates to the technical field of coatings, in particular to a steel rail radiation heat dissipation coating and a preparation method thereof. The coating comprises a component A and a component B, wherein the component A comprises the following raw materials: 1-2 parts of cellulose, 1-5 parts of a first pH regulator, 20-40 parts of metal oxide powder, 3-10 parts of a molybdic acid compound, 5-10 parts of graphene oxide, 1-5 parts of a metal salt solution, 1-10 parts of a second pH regulator, 25-60 parts of an epoxy modified styrene-acrylic emulsion and 50-300 parts of water; the component B comprises the following raw materials in parts by weight: 100-200 parts of polyamide resin, 50-100 parts of an amine compound, 5-20 parts of a vulcanization accelerator and 1-10 parts of a plasticizer. The coating disclosed by the invention is strong in adhesive force and can be stably used under a low-temperature condition; meanwhile, the heat conductivity is good, the reflectivity in the wavelength range of visible light and infrared light is high, the emissivity in the wavelength range of an atmospheric window is high, and the effects of reflective heat insulation and radiation refrigeration can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a rail radiation heat dissipation coating and a preparation method thereof. Background Art

[0002] The wavelength range of sunlight is roughly between 0.15 and 4.0 μm. Of all the radiation energy, wavelengths between 0.15 and 4 μm account for more than 99%, and are mainly distributed in the visible light region (0.4 to 0.76 μm) and the infrared region (>0.76 μm). The former accounts for about 50% of the total solar radiation energy, and the latter accounts for about 43%. The solar radiation energy in the ultraviolet region is very small (<0.4 μm), accounting for only about 7% of the total.

[0003] Various substances on the earth's surface, as long as their temperature is higher than absolute zero (-273.5℃), will radiate energy to the outside world, and discharge their own heat in the form of infrared electromagnetic waves into outer space where the temperature is close to absolute zero, thereby achieving the purpose of self-cooling; the "atmospheric window" band is mainly in the range of 8 to 13μm, and the earth's atmosphere has the characteristics of low absorption in this band.

[0004] There are many existing studies on radiant heat dissipation coatings, but there is relatively little research on radiant heat dissipation coatings used on rails. Due to the particularity of the application process, existing coatings often have insufficient adhesion during application and are prone to coating shedding due to vibration and friction, causing inconvenience to use.

[0005] Therefore, the present invention proposes a radiant heat dissipation coating and a preparation method thereof. The produced cold radiation coating has high visible light reflectivity and infrared reflectivity, high emissivity at the atmospheric window, good adhesion and stability, and can dissipate heat, making it easy to use on rails. Summary of the invention

[0006] The purpose of the present invention is to provide a rail radiant heat dissipation coating and a preparation method thereof, so as to solve the problem that the existing radiant heat dissipation coating has poor adhesion and is easily peeled off by vibration and friction when applied on the rail, thus affecting the stability of use.

[0007] To achieve the above object, the present invention adopts the following technical solution: a rail radiation heat dissipation coating, the coating comprising component A and component B;

[0008] The A component comprises the following raw materials in parts by weight:

[0009] 1-2 parts of cellulose, 1-5 parts of a first pH regulator, 20-40 parts of metal oxide powder, 3-10 parts of a molybdate compound, 5-10 parts of graphene oxide, 1-5 parts of a metal salt solution, 1-10 parts of a second pH regulator, 25-60 parts of an epoxy-modified styrene-acrylic emulsion, and 50-300 parts of water;

[0010] The B component includes the following raw materials in parts by weight:

[0011] 100-200 parts of polyamide resin, 50-100 parts of amine compound, 5-20 parts of vulcanization accelerator, and 1-10 parts of plasticizer.

[0012] Furthermore, the component A also includes the following raw materials in parts by weight:

[0013] 1-10 parts of wetting agent, 1-20 parts of dispersant, 1-15 parts of defoaming agent, 1-10 parts of leveling agent, 1-10 parts of polypropylene glycol, 1-5 parts of film-forming aid, 5-10 parts of filler, 1-6 parts of thickener, and 1-3 parts of bactericide.

[0014] Furthermore, the metal oxide powder includes nano-aluminum oxide, reflective heat-insulating titanium dioxide and nano-chromium oxide, and the weight ratio of nano-aluminum oxide, reflective heat-insulating titanium dioxide and nano-chromium oxide is 1:2:1.

[0015] Furthermore, the concentration of the solute in the metal salt solution is 0.2 mol / L, and the solute includes aluminum chloride, titanium tetrachloride and chromium chloride, and the molar concentration ratio of aluminum chloride, titanium tetrachloride and chromium chloride is 1:2:1.

[0016] Furthermore, the cellulose is sodium carboxymethyl cellulose, the first pH regulator is AMP-95, the wetting agent is X-405, the dispersant is 5040, the defoaming agent is NXZ, the leveling agent is BYK-3455, the polypropylene glycol is PPG-200, the film-forming aid is C-12, the filler is kaolin DB3000, the nano-alumina is TAP-A02, the reflective heat-insulating titanium dioxide is titanium dioxide 550, and the nano-chromium oxide is AM-Cr2O3-N-02. The molybdate compound is a lanthanum molybdate compound modified by iron ions, the thickener is SN612 and / or L344, the bactericide is LXE, the graphene oxide is DN-20DY, the second pH adjuster is 2% sodium hydroxide solution, the polyamide resin is polyamide resin 650, the amine compound is diethylenetriamine, the vulcanization accelerator is vulcanization accelerator M, the plasticizer is dibutyl phthalate and dioctyl adipate, and the ratio of dibutyl phthalate to dioctyl adipate is 2:1.

[0017] The preparation method of the rail radiation heat dissipation coating comprises the following steps:

[0018] S11, dispersing graphene oxide, water, a dispersant and a defoaming agent uniformly; dropping a metal salt solution into the mixed system, and simultaneously dropping a second pH regulator to maintain the pH of the mixed system to be weakly acidic; after the reaction is completed, solid-liquid separation and calcination are performed to obtain a graphene oxide solid phase;

[0019] S12, mix cellulose, water and the first pH adjuster, add a wetting agent, a dispersant, a defoaming agent, a leveling agent, polypropylene glycol, and a film-forming aid after uniform dispersion and continue to disperse; add fillers, nano-alumina, molybdate compounds, reflective thermal insulation titanium dioxide, nano-chromium oxide and the graphene oxide solid phase obtained in S1 after uniform dispersion and continue to disperse; add epoxy-modified styrene-acrylic emulsion, a defoaming agent, a thickener and a bactericide after uniform dispersion, and obtain component A of the present invention after uniform dispersion.

[0020] Furthermore, the preparation of the molybdate compound comprises the following steps:

[0021] S21, taking ferric chloride and lanthanum molybdate, and mixing them evenly in a ball mill, wherein the ball milling medium is anhydrous ethanol;

[0022] S22, roasting the obtained mixture, and then washing, filtering and drying to obtain the molybdic acid compound of the present invention.

[0023] Furthermore, the preparation of the epoxy-modified styrene-acrylic emulsion comprises the following steps:

[0024] S31, taking epoxy resin, methyl methacrylate, styrene, butyl acrylate and methacrylic acid, and mixing them evenly in water under the action of emulsifier and buffer;

[0025] S32, adding an initiator to react, and after the reaction is completed, continuing to add epoxy resin, neutralizing with a neutralizer, and cooling to obtain the epoxy-modified styrene-acrylic emulsion of the present invention.

[0026] Furthermore, the preparation of the B component comprises the following steps:

[0027] S41, uniformly mixing the polyamide resin and the amine compound, and reacting them under a certain temperature condition;

[0028] S42, after the reaction is completed, continue to add vulcanization accelerator and plasticizer, react again and then cool to obtain component B of the present invention.

[0029] Furthermore, the component A and the component B are uniformly mixed in a ratio of 5 to 10:1 during use.

[0030] Beneficial effects of the present invention:

[0031] 1. The coating of the present invention has good adhesion, can be stably coated on the rail during use, is not easy to fall off under the conditions of friction heat and vibration, and is more stable to use;

[0032] 2. The coating of the present invention can be stably and quickly cured at a lower temperature, and has stable performance, thereby improving the efficiency of construction and being more convenient to use;

[0033] 3. The coating of the present invention can quickly conduct the heat generated by the friction of the rails and then dissipate it, and has a reflective heat-insulating effect, which can reduce the heat of the rails to the greatest extent and play a positive role in ensuring the service life of the rails. DETAILED DESCRIPTION

[0034] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0035] Example 1

[0036] Various raw materials are used in the preparation process of the coating of this embodiment. In order to clearly and completely describe the coating of the present invention, the raw materials used in the coating of the present invention are described as shown in the following table:

[0037] Table 1 Raw materials of rail cold radiation coating in this embodiment

[0038]

[0039] The cellulose is sodium carboxymethyl cellulose; the first pH regulator is AMP-95; the wetting agent is X-405; the dispersant is 5040; the defoamer is NXZ; the leveling agent is BYK-3455; the polypropylene glycol is PPG-200; the film-forming aid is C-12; the filler is kaolin DB3000; the nano-alumina is TAP-A02; the reflective heat-insulating titanium dioxide is titanium dioxide 550; the nano-chromium oxide is AM-Cr2O3-N-02; the molybdate compound is a lanthanum molybdate compound modified by iron ions; and the thickener is SN612 and / or L344; The bactericide is LXE; the graphene oxide is DN-20DY; the concentration of the solute in the metal salt solution is 0.2 mol / L, and the solute includes aluminum chloride, titanium tetrachloride and chromium chloride, and the molar concentration ratio of aluminum chloride, titanium tetrachloride and chromium chloride is 1:2:1; the second pH adjuster is 2% sodium hydroxide solution; the polyamide resin is polyamide resin 650; the amine compound is diethylenetriamine; the vulcanization accelerator is vulcanization accelerator M; the plasticizer is dibutyl phthalate and dioctyl adipate, and the ratio of dibutyl phthalate to dioctyl adipate is 2:1.

[0040] The raw materials in this embodiment involve molybdic acid compounds, and the preparation method is as follows:

[0041] Take ferric chloride (FeCl3·6H2O, AR) and lanthanum molybdate [La2(MoO4)3, AR], the molar ratio of ferric chloride to lanthanum molybdate is 1:10; mechanically mix the ferric chloride and lanthanum molybdate in a ball mill, use zirconium oxide grinding balls with a diameter of 3mm, and use anhydrous ethanol as the ball milling medium, the mass ratio of the raw materials, grinding balls and anhydrous ethanol is 1:2:5, the ball milling time is 2h, and the rotation speed is 100rpm; after the ball milling is completed, the solid-liquid separation and the grinding balls are separated, the solid mixed material is placed in a muffle furnace for roasting, the roasting temperature is 500°C, and the roasting time is 4h; after the roasting is completed, it is cooled, washed with water, filtered, and dried to obtain the molybdate compound of this embodiment.

[0042] The raw materials in this embodiment also involve epoxy-modified styrene-acrylic emulsion, and the preparation method is as follows:

[0043] Take 4 parts by weight of emulsifier (DF-2, 1wt.% and OP-10, 1wt.%; weight ratio is 1:1), 1 part by weight of buffer (sodium bicarbonate, 0.5wt.%) and dissolve them in 100 parts by weight of water, stir at 200rpm, and heat to 80°C; take 1 part by weight of epoxy resin (E20, 5wt.%), 1 part by weight of methyl methacrylate (4wt.%), 4 parts by weight of styrene (45wt.%), 1 part by weight of butyl acrylate (49wt.%) and 1 part by weight of methacrylic acid (2wt.%), dissolve and mix evenly in water under continuous stirring; add 1 part by weight of initiator ammonium persulfate (0.5wt.%), and continue to react for 1h to obtain a seed emulsion; add the obtained Continue to drop 4 parts by weight of epoxy resin (E20, 5wt.%), 4 parts by weight of methyl methacrylate (4wt.%), 16 parts by weight of styrene (45wt.%), 4 parts by weight of butyl acrylate (49wt.%) and 4 parts by weight of methacrylic acid (2wt.%) into the seed emulsion, and at the same time, drop 3 parts by weight of initiator ammonium persulfate (0.5wt.%), so that the initiator and the raw materials are added synchronously within 4h. After the addition is completed, continue to stir and react for 30min, and then continue to add 2 parts by weight of epoxy resin (E20, 5wt.%) to the reaction system, add a neutralizer (triethylamine, 1wt.%) after the addition is completed, continue to stir for 30min, and cool to obtain the epoxy-modified styrene-acrylic emulsion of this embodiment.

[0044] The raw materials in this embodiment also involve a graphene oxide solid phase, and the preparation method is as follows:

[0045] Take 5 parts of graphene oxide, 10 parts of dispersant and 5 parts of defoaming agent, put them in 100 parts of water, stir at 200 rpm and disperse them evenly; take 3 parts of metal salt solution and slowly add them dropwise to the mixed system, and at the same time add a second pH adjuster to maintain the pH of the mixed system at 5-7 until the metal salt solution is added, at which time the reaction is completed; after the reaction is completed, the solid and liquid are separated, and the obtained solid component is placed in a muffle furnace for roasting at a temperature of 600°C and a roasting time of 6 hours to obtain a graphene oxide solid phase.

[0046] The molybdate compound, epoxy-modified styrene-acrylic emulsion and graphene oxide solid phase prepared in this embodiment are taken together with existing raw materials to prepare the coating of the present invention. The preparation process of component A in the coating of the present invention is as follows:

[0047] Add 50 parts by weight of water to the dispersion kettle, add 1 part by weight of cellulose and 2 parts by weight of the first pH regulator AMP-95 at a speed of 400 rpm, increase the speed to 800 rpm and disperse for 30 minutes until the cellulose is completely opened; reduce the speed to 400 rpm, slowly add 5 parts by weight of wetting agent, 10 parts by weight of dispersant, 5 parts by weight of defoamer, 5 parts by weight of leveling agent, and continue to disperse for 5 minutes; slowly add 5 parts by weight of polypropylene glycol and 3 parts by weight of film-forming aid in sequence, and disperse for 5 minutes; add 5 parts by weight of nano alumina, 10 parts by weight of reflective heat insulation Titanium dioxide, 5 parts by weight of nano-chromium oxide, 5 parts by weight of filler, 5 parts by weight of molybdate compound, 5 parts by weight of graphene oxide, increase the speed to 1200rmp, high-speed dispersion for 30min, then reduce the speed to 600rmp, add 40 parts by weight of epoxy-modified styrene-acrylic emulsion and 5 parts by weight of defoamer, and disperse for 3min; slowly add 3 parts by weight of thickener (the thickener is diluted with water in advance at a weight ratio of 1:3), control the speed, and make the slurry with a small vortex in the middle for the best, then add 3 parts by weight of bactericide, disperse for 3min, and you can get component A of this embodiment.

[0048] The preparation process of component B in the coating of the present invention is as follows:

[0049] Take 100 parts by weight of polyamide resin and 50 parts by weight of amine compound, stir and mix evenly at 200 rpm, heat to 120°C, and continue stirring to react for 4 hours; after the reaction is completed, cool to 80°C, continue to add 5 parts by weight of vulcanization accelerator and 5 parts by weight of plasticizer, continue stirring to react for 2 hours, cool and package after the reaction is completed, and you can get component B of this embodiment.

[0050] The component A and component B obtained in this example were mixed evenly at a ratio of 10:1, and then coated on the rail. The coating parameters and performance of this example are recorded as follows:

[0051] When the coating obtained in this embodiment is applied under the experimental condition of -5°C, curing can be completed in 6 hours, which effectively improves the efficiency of construction; at the same time, the reflectivity of the coating obtained can reach 98.33% between 0.15 and 4 μm, and the emissivity can reach 97.82% at 8 to 13 μm, with excellent performance; under the outdoor condition of 35.6°C, the surface of the rail coated with the coating of this embodiment is only 22.1°C, and the temperature reduction can reach 13.5°C; in addition, when the rail coated with the coating of this embodiment is heated, the outdoor temperature is 29.5°C during the process, the initial temperature of the rail is 20.4°C, the rail is heated to 40°C, and then placed in the air, it can be reduced to the initial level in only about 3 minutes, and has good heat dissipation. It can be seen that the coating of the present invention plays a positive and beneficial role in ensuring the service life of the rail.

[0052] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to those of the present application fall within the protection scope of the present invention.

Claims

1. A rail radiation heat dissipation coating, characterized in that: The coating comprises component A and component B; The A component comprises the following raw materials in parts by weight: 1-2 parts of cellulose, 1-5 parts of a first pH regulator, 20-40 parts of metal oxide powder, 3-10 parts of a molybdate compound, 5-10 parts of graphene oxide, 1-5 parts of a metal salt solution, 1-10 parts of a second pH regulator, 25-60 parts of an epoxy-modified styrene-acrylic emulsion, and 50-300 parts of water; The B component includes the following raw materials in parts by weight: 100-200 parts of polyamide resin, 50-100 parts of amine compound, 5-20 parts of vulcanization accelerator, and 1-10 parts of plasticizer.

2. The rail radiation heat dissipation coating according to claim 1, characterized in that: The A component also includes the following raw materials in parts by weight: 1-10 parts of wetting agent, 1-20 parts of dispersant, 1-15 parts of defoaming agent, 1-10 parts of leveling agent, 1-10 parts of polypropylene glycol, 1-5 parts of film-forming aid, 5-10 parts of filler, 1-6 parts of thickener, and 1-3 parts of bactericide.

3. The rail radiation heat dissipation coating according to claim 1, characterized in that: The metal oxide powder includes nano aluminum oxide, reflective heat-insulating titanium dioxide and nano chromium oxide, and the weight ratio of the nano aluminum oxide, the reflective heat-insulating titanium dioxide and the nano chromium oxide is 1:2:

1.

4. The rail radiation heat dissipation coating according to claim 1, characterized in that: The concentration of the solute in the metal salt solution is 0.2 mol / L, and the solute includes aluminum chloride, titanium tetrachloride and chromium chloride, and the molar concentration ratio of aluminum chloride, titanium tetrachloride and chromium chloride is 1:2:

1.

5. A rail radiation heat dissipation coating according to any one of claims 1 to 4, characterized in that: The cellulose is sodium carboxymethyl cellulose, the first pH regulator is AMP-95, the wetting agent is X-405, the dispersant is 5040, the defoamer is NXZ, the leveling agent is BYK-3455, the polypropylene glycol is PPG-200, the film-forming aid is C-12, the filler is kaolin DB3000, the nano-alumina is TAP-A02, the reflective heat-insulating titanium dioxide is titanium dioxide 550, the nano-chromium oxide is AM-Cr2O3-N-02, and the molybdenum oxide is The compound is a lanthanum molybdate compound modified by iron ions, the thickener is SN612 and / or L344, the bactericide is LXE, the graphene oxide is DN-20DY, the second pH adjuster is 2% sodium hydroxide solution, the polyamide resin is polyamide resin 650, the amine compound is diethylenetriamine, the vulcanization accelerator is vulcanization accelerator M, the plasticizers are dibutyl phthalate and dioctyl adipate, and the ratio of dibutyl phthalate to dioctyl adipate is 2:

1.

6. The method for preparing the rail radiation heat dissipation coating according to any one of claims 1 to 5, characterized in that: The preparation of the A component comprises the following steps: S11, dispersing graphene oxide, water, a dispersant and a defoaming agent uniformly; dropping a metal salt solution into the mixed system, and simultaneously dropping a second pH regulator to maintain the pH of the mixed system to be weakly acidic; after the reaction is completed, solid-liquid separation and calcination are performed to obtain a graphene oxide solid phase; S12, mix cellulose, water and the first pH adjuster, add a wetting agent, a dispersant, a defoaming agent, a leveling agent, polypropylene glycol, and a film-forming aid after uniform dispersion and continue to disperse; add fillers, nano-alumina, molybdate compounds, reflective thermal insulation titanium dioxide, nano-chromium oxide and the graphene oxide solid phase obtained in S1 after uniform dispersion and continue to disperse; add epoxy-modified styrene-acrylic emulsion, a defoaming agent, a thickener and a bactericide after uniform dispersion, and obtain component A of the present invention after uniform dispersion.

7. The method for preparing the rail radiation heat dissipation coating according to claim 6, characterized in that: The preparation of the molybdate compound comprises the following steps: S21, taking ferric chloride and lanthanum molybdate, and mixing them evenly in a ball mill, wherein the ball milling medium is anhydrous ethanol; S22, roasting the obtained mixture, and then washing, filtering and drying to obtain the molybdic acid compound of the present invention.

8. The method for preparing the rail radiation heat dissipation coating according to claim 6, characterized in that: The preparation of the epoxy-modified styrene-acrylic emulsion comprises the following steps: S31, taking epoxy resin, methyl methacrylate, styrene, butyl acrylate and methacrylic acid, and mixing them evenly in water under the action of emulsifier and buffer; S32, adding an initiator to react, and after the reaction is completed, continuing to add epoxy resin, neutralizing with a neutralizer, and cooling to obtain the epoxy-modified styrene-acrylic emulsion of the present invention.

9. The method for preparing the rail radiation heat dissipation coating according to claim 6, characterized in that: The preparation of the B component comprises the following steps: S41, uniformly mixing the polyamide resin and the amine compound, and reacting them under a certain temperature condition; S42, after the reaction is completed, continue to add vulcanization accelerator and plasticizer, react again and then cool to obtain component B of the present invention.

10. The method for preparing the rail radiation heat dissipation coating according to any one of claims 6 to 9, characterized in that: The component A and the component B are evenly mixed in a ratio of 5 to 10:1 during use.

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