An antistatic coating for running boards and its preparation method

Abstract

This invention relates to the field of coating preparation technology, and discloses an antistatic coating for running boards and its preparation method. The antistatic coating comprises the following raw materials in parts by weight: 100-120 parts of composite emulsion, 10-20 parts of dispersant, 5-10 parts of defoamer, 10-15 parts of stabilizer, 30-40 parts of zinc oxide, 10-20 parts of ultrafine aluminum silicate, 30-40 parts of titanium dioxide, and 40-60 parts of deionized water. The composite emulsion is prepared by copolymerization of modified monomers, acrylate monomers, and modified fillers initiated by potassium persulfate. The strong electronegativity of fluorine atoms on the modified monomer chains forms a low surface energy structure on the coating surface, giving the polyacrylate material excellent resistance to sweat corrosion. At the same time, the modified filler is chemically inert, blocking the penetration of water vapor and corrosive media, and improving the material's corrosion resistance. The modified filler is linked with polymer molecules to form a mesh structure, which can disperse stress and improve the coating's wear resistance. The composite emulsion improves the material's antistatic properties by reducing the material's resistance and increasing the conductivity of carbon black.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, specifically to an antistatic coating for running boards and its preparation method. Background Technology

[0002] With economic development, more and more people are using treadmills for fitness. However, as the treadmill is used for extended periods, the friction between the running board, rollers, running belt, and shoe soles can lead to the accumulation of static electricity. This static electricity buildup can pose safety hazards, such as excessive static electricity affecting the user's personal safety and static interference causing garbled characters on the display screen, thus affecting the treadmill's precise speed control. Therefore, using antistatic coatings has become a solution to these problems.

[0003] Antistatic coatings typically consist of resins, curing agents, fillers, and conductive materials. After application and curing, these components form a robust coating with antistatic properties. Furthermore, antistatic coatings are easy to apply and maintain, making them a promising functional coating material for applications in the electronics, automotive, and medical industries.

[0004] While the application of antistatic coatings to running boards has solved the static electricity problem to some extent, the antistatic effect of the coatings currently used on running boards is weak. Furthermore, with the increase in usage time, the rapid friction between the running board and the rollers, running belt, and shoe soles will also cause physical wear on the surface of the coating on the running board. The running board is also prone to corrosion and penetration due to prolonged contact with sweat. All of these factors will lead to a decline in the antistatic performance, wear resistance, and corrosion resistance of the antistatic coating, which will affect the service life of the coating on the running board.

[0005] Therefore, it is necessary to develop a new antistatic coating for running boards and modify the key components of existing antistatic coatings to solve the problems that arise in practical applications. Summary of the Invention

[0006] The purpose of this invention is to provide an antistatic coating for running boards and its preparation method, which solves the problems of weak antistatic effect, poor resistance to sweat corrosion, and poor wear resistance of current coatings for running boards.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] A method for preparing an antistatic coating for running boards specifically includes the following steps:

[0009] Step S1: Mix the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, modified filler and deionized water evenly. Stir and add potassium persulfate at a speed of 150-200 r / min and a temperature of 25-30℃ for 4 hours. Then raise the temperature to 90-100℃ and continue to react for 1-2 hours to obtain the composite emulsion.

[0010] Step S2: Weigh the following raw materials in parts by weight: 100-120 parts of composite emulsion, 10-20 parts of dispersant, 5-10 parts of defoamer, 10-15 parts of stabilizer, 30-40 parts of zinc oxide, 10-20 parts of ultrafine aluminum silicate, 30-40 parts of titanium dioxide and 40-60 parts of deionized water. Mix the raw materials evenly to obtain an antistatic coating.

[0011] Furthermore, the weight ratio of the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, potassium persulfate, deionized water and modified filler in step S1 is 100-120:180-200:110-130:50-70:1-3:55-70:60-80.

[0012] Furthermore, the dispersant mentioned in step S2 is one or more of ACUMER 9300, OROTAN 1124 and DispesUltra PA 4560 mixed in any proportion; the defoamer is one or more of BYK-024, BYK-052N and DC62 mixed in any proportion; the stabilizer is one or more of Tinuvin 292, Tinuvin 123, Tinuvin 1130 and Tinuvin 400 mixed in any proportion; the ultrafine aluminum silicate is aluminum silicate powder with an average particle size ≤1.5μm and whiteness ≥97%; and the titanium dioxide is one or more of PA101, R-960, SR-237 and R706 mixed in any proportion.

[0013] Furthermore, the modified monomer is prepared by the following steps:

[0014] Step A1: Mix tridecylfluorooctyl alcohol, boron trifluoride ether and acetone evenly, stir and add epichlorohydrin at a speed of 150-200 r / min and a temperature of 25-30℃, raise the temperature to 70-75℃ and react for 5-8 h, add sodium hydroxide solution and react for 3-5 h to obtain intermediate 1.

[0015] Step A2: Mix intermediate 1, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add diethanolamine at 120-150 r / min and 20-25℃, and react for 2-3 h to obtain intermediate 2. Mix intermediate 2 and acetonitrile evenly, stir and add benzyl chloride and bromoethane at 110-130 r / min and 60-70℃, and react for 3-4 h to obtain intermediate 3.

[0016] Step A3: Mix intermediate 3, acrylic acid and dimethylformamide evenly. Stir and add perfluorobutylsulfonate ammonium and p-hydroxyanisole at a speed of 200-300 r / min and a temperature of 20-25℃. After stirring for 10 min, raise the temperature to 80℃ and react for 2-3 h. Then raise the temperature to 90℃ and react for 2-3 h to obtain the modified monomer.

[0017] Furthermore, in step A1, the ratio of tridecafluorooctol, epichlorohydrin, and sodium hydroxide solution is 10 mmol:10 mmol:25 mL, the amount of boron trifluoride ether is 3-5% of the mass of tridecafluorooctol, and the mass fraction of sodium hydroxide solution is 25%.

[0018] Furthermore, in step A2, the molar ratio of the epoxy group on intermediate 1 to the secondary amine on diethanolamine is 1:1, the mass fraction of ZnCl2 solution is 5-10%, the amount of ZnCl2 solution used is 3-5% of the mass of diethanolamine, and the molar ratio of intermediate 2, acetonitrile, benzyl chloride and bromoethane is 1:1.5:1.5:1.

[0019] Furthermore, in step A3, the molar ratio of the hydroxyl group on intermediate 3 to the carboxyl group on acrylic acid is 1:1, the amount of ammonium perfluorobutyl sulfonate is 3-5% of the mass of acrylic acid, and the amount of p-hydroxyanisole is 1% of the mass of acrylic acid.

[0020] Furthermore, the modified filler is prepared by the following steps:

[0021] Step B1: Mix hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol and ammonia water evenly. Under the conditions of 200-250 r / min, 20-25℃, and pH 7-8, stir and add γ-glycidoxypropyltrimethoxysilane and tetraethyl orthosilicate. Raise the temperature to 55-65℃ and react for 4-6 h. Raise the temperature to 80-90℃, add nano-alumina, stir for 10-20 min, and then age for 10-15 h to obtain pretreated silica.

[0022] Step B2: Disperse carbon black in ethanol, and stir and add deionized water and 3-aminopropyltriethoxysilane at a speed of 200-300 r / min, a temperature of 60-80℃, and a pH of 4-5 to obtain pretreated carbon black.

[0023] Step B3: Mix pretreated silica, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add pretreated carbon black at a speed of 120-150 r / min and a temperature of 20-25℃, and react for 2-3 hours to obtain composite filler. Mix composite filler, acrylic acid and ethanol evenly, stir and add concentrated sulfuric acid at a speed of 300-500 r / min and a temperature of 80-90℃, and react for 2-3 hours to obtain modified filler.

[0024] Furthermore, in step B1, the ratio of hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol, ammonia, and tetraethyl orthosilicate is 0.35g:100mL:60mL:2mL:1.80g, the amount of γ-glycidoxypropyltrimethoxysilane is 1-5% of the mass of tetraethyl orthosilicate, and the amount of nano-alumina is 20-35% of the mass of tetraethyl orthosilicate.

[0025] Furthermore, the amount of 3-aminopropyltriethoxysilane used in step B2 is 5-10% of the mass of carbon black.

[0026] Furthermore, in step B3, the ratio of pretreated silica, pretreated carbon black, and ZnCl2 solution is 2.5g:1.7g:10mL, the mass fraction of ZnCl2 solution is 5-10%, and the ratio of composite filler, acrylic acid, and concentrated sulfuric acid is 6.5g:10mL:2mL, the mass fraction of concentrated sulfuric acid is 95%.

[0027] The beneficial effects of the present invention: The antistatic coating for running boards prepared by the present invention includes the following raw materials: composite emulsion, dispersant, defoamer, stabilizer, zinc oxide, ultrafine aluminum silicate, titanium dioxide and deionized water. The composite emulsion is prepared by mixing and reacting modified monomers, methyl acrylate, methyl methacrylate, glycidyl methacrylate, modified filler and deionized water.

[0028] Modified monomer: The hydroxyl group on tridecafluorooctyl alcohol reacts with the epoxy group on epichlorohydrin to undergo a nucleophilic substitution reaction to generate an ether. Then, under the action of sodium hydroxide solution, the ring is closed to form a new epoxy group, thus obtaining intermediate 1. Intermediate 1 is reacted with diethanolamine to open the ring, and the CO bond of the epoxy ring is broken to form a stable β-hydroxyamine product intermediate 2. Intermediate 2 is reacted with bromoethane to undergo a secondary amine quaternization reaction to generate intermediate 3. Intermediate 3 is reacted with acrylic acid, so that the hydroxyl group on intermediate 3 undergoes an esterification reaction with the carboxyl group on acrylic acid to obtain the modified monomer.

[0029] Modified fillers: The ethoxy group of tetraethyl orthosilicate reacts with water to form silanols. The methoxy group of γ-glycidoxypropyltrimethoxysilane hydrolyzes to silanols under alkaline conditions. These silanols then condense to form stable Si-O-Si bonds (i.e., SiO2). With the addition of nano-alumina, the silanols condense with the hydroxyl groups on the surface of the nano-alumina to form stable Si-O-Al bonds, yielding pretreated silica. The ethoxy group of 3-aminopropyltriethoxysilane hydrolyzes to silanols under acidic conditions, which condense with the hydroxyl groups on the surface of carbon black to form stable Si-OC bonds, allowing the amino segments of 3-aminopropyltriethoxysilane to be grafted onto the carbon black surface, yielding pretreated carbon black. The hydroxyl groups of the composite filler and the carboxyl groups of acrylic acid undergo esterification under the catalysis of concentrated sulfuric acid, introducing carbon-carbon double bonds into the composite filler, thus obtaining modified fillers.

[0030] The polymer molecules in the composite emulsion contain quaternary ammonium salts, whose hydrophilic groups can ionize and form an ionic conductive network, reducing the surface resistance of the material. The microporous structure of carbon black on the modified filler molecular chains can adsorb environmental moisture and enhance ionic conductivity through a proton hopping mechanism, improving the material's antistatic properties. The strong electronegativity of fluorine atoms enables the formation of a low surface energy structure on the coating surface, giving polyacrylate materials excellent resistance to strong acids and alkalis. The modified filler is chemically inert, blocking the penetration of water vapor and corrosive media, thus improving the material's corrosion resistance. The high Mohs hardness of nano-alumina significantly improves the coating's scratch and abrasion resistance. The modified filler and polymer molecules are linked together to form a mesh structure. This mesh structure can disperse stress, preventing cracks in the coating due to substrate shrinkage or vibration, and improving the material's mechanical properties. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1: A method for preparing an antistatic coating for a running board, specifically including the following steps:

[0033] Step S1: Mix the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, modified filler and deionized water evenly. Stir and add potassium persulfate at 150 r / min and 25℃ for 4 h. Then raise the temperature to 90℃ and continue to react for 1 h to prepare the composite emulsion.

[0034] Step S2: Weigh the following raw materials by weight: 100 parts of composite emulsion, 10 parts of dispersant, 5 parts of defoamer, 10 parts of stabilizer, 30 parts of zinc oxide, 10 parts of ultrafine aluminum silicate, 30 parts of titanium dioxide and 40 parts of deionized water. Mix the raw materials evenly to obtain an antistatic coating.

[0035] The weight ratio of the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, potassium persulfate, deionized water and modified filler in step S1 is 100:180:110:50:1:55:60.

[0036] The dispersant mentioned in step S2 is a mixture of ACUMER 9300, OROTAN 1124 and Dispes Ultra PA 4560 in a mass ratio of 1:1.3:1.7; the defoamer is BYK-024; the stabilizer is a mixture of Tinuvin 292 and Tinuvin 123 in a mass ratio of 1:1.3; the ultrafine aluminum silicate is aluminum silicate powder with an average particle size ≤1.5μm and whiteness ≥97%; and the titanium dioxide is a mixture of PA101, R-960, SR-237 and R706 in a mass ratio of 1:1.3:1.7:1.4.

[0037] The modified monomer is prepared by the following steps:

[0038] Step A1: Mix tridecylfluorooctyl alcohol, boron trifluoride ether and acetone evenly, stir and add epichlorohydrin at 150 r / min and 25°C, heat to 70°C and react for 5 h, add sodium hydroxide solution and react for 3 h to obtain intermediate 1.

[0039] Step A2: Mix intermediate 1, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add diethanolamine at 120 r / min and 20℃, and react for 2 h to obtain intermediate 2. Mix intermediate 2 and acetonitrile evenly, stir and add benzyl chloride and bromoethane at 110 r / min and 60℃, and react for 3 h to obtain intermediate 3.

[0040] Step A3: Mix intermediate 3, acrylic acid and dimethylformamide evenly. Stir at 200 r / min and 20°C, and add perfluorobutyl sulfonate and p-hydroxyanisole. Stir for 10 min, then heat to 80°C and react for 2 h. Then heat to 90°C and react for 2 h to obtain the modified monomer.

[0041] In step A1, the ratio of tridecafluorooctol, epichlorohydrin, and sodium hydroxide solution is 10 mmol:10 mmol:25 mL, the amount of boron trifluoride ether is 3% of the mass of tridecafluorooctol, and the mass fraction of sodium hydroxide solution is 25%.

[0042] In step A2, the molar ratio of the epoxy group on intermediate 1 to the secondary amine on diethanolamine is 1:1, the mass fraction of ZnCl2 solution is 5%, the amount of ZnCl2 solution used is 3% of the mass of diethanolamine, and the molar ratio of intermediate 2, acetonitrile, benzyl chloride and bromoethane is 1:1.5:1.5:1.

[0043] In step A3, the molar ratio of the hydroxyl group on intermediate 3 to the carboxyl group on acrylic acid is 1:1, the amount of perfluorobutylsulfonate ammonium is 3% of the mass of acrylic acid, and the amount of p-hydroxyanisole is 1% of the mass of acrylic acid.

[0044] The modified filler is prepared by the following steps:

[0045] Step B1: Mix hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol and ammonia water evenly. Stir at 200 r / min, 20℃, and pH 7, and add γ-glycidoxypropyltrimethoxysilane and tetraethyl orthosilicate. Heat to 55℃ and react for 4 h. Heat to 80℃, add nano-alumina, stir for 10 min, and age for 10 h to obtain pretreated silica.

[0046] Step B2: Disperse carbon black in ethanol, stir and add deionized water and 3-aminopropyltriethoxysilane at a speed of 200 r / min, a temperature of 60℃ and a pH of 4, and react for 8 h to obtain pretreated carbon black.

[0047] Step B3: Mix pretreated silica, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add pretreated carbon black at 120 r / min and 20℃, and react for 2 h to obtain composite filler. Mix composite filler, acrylic acid and ethanol evenly, stir and add concentrated sulfuric acid at 300 r / min and 80℃, and react for 2 h to obtain modified filler.

[0048] In step B1, the ratio of hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol, ammonia, and tetraethyl orthosilicate is 0.35 g: 100 mL: 60 mL: 2 mL: 1.80 g, the amount of γ-glycidoxypropyltrimethoxysilane is 1% of the mass of tetraethyl orthosilicate, and the amount of nano-alumina is 20% of the mass of tetraethyl orthosilicate.

[0049] The amount of 3-aminopropyltriethoxysilane used in step B2 is 5% of the mass of carbon black.

[0050] In step B3, the ratio of pretreated silica, pretreated carbon black, and ZnCl2 solution is 2.5g:1.7g:10mL, and the ZnCl2 solution has a mass fraction of 5%. The ratio of composite filler, acrylic acid, and concentrated sulfuric acid is 6.5g:10mL:2mL, and the concentrated sulfuric acid has a mass fraction of 95%.

[0051] Example 2, a method for preparing an antistatic coating for a running board, specifically includes the following steps:

[0052] Step S1: Mix the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, modified filler and deionized water evenly. Stir and add potassium persulfate at 160 r / min and 27°C for 4 h. Then raise the temperature to 100°C and continue the reaction for 1.5 h to prepare the composite emulsion.

[0053] Step S2: Weigh the following raw materials by weight: 110 parts of composite emulsion, 15 parts of dispersant, 7 parts of defoamer, 13 parts of stabilizer, 35 parts of zinc oxide, 15 parts of ultrafine aluminum silicate, 35 parts of titanium dioxide and 45 parts of deionized water. Mix the raw materials evenly to obtain an antistatic coating.

[0054] The weight ratio of the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, potassium persulfate, deionized water and modified filler in step S1 is 110:190:120:60:2:60:70.

[0055] The dispersant mentioned in step S2 is a mixture of ACUMER 9300, OROTAN 1124 and Dispes Ultra PA 4560 in a mass ratio of 1:1.4:1.3; the defoamer is BYK-024; the stabilizer is a mixture of Tinuvin 292 and Tinuvin 123 in a mass ratio of 1:1.2; the ultrafine aluminum silicate is aluminum silicate powder with an average particle size ≤1.5μm and whiteness ≥97%; and the titanium dioxide is a mixture of PA101, R-960, SR-237 and R706 in a mass ratio of 1:1.3:1.4:1.2.

[0056] The modified monomer is prepared by the following steps:

[0057] Step A1: Mix tridecylfluorooctyl alcohol, boron trifluoride ether and acetone evenly, stir and add epichlorohydrin at 170 r / min and 27°C, heat to 72°C and react for 6 h, add sodium hydroxide solution and react for 4 h to obtain intermediate 1.

[0058] Step A2: Intermediate 1, ZnCl2 solution and dimethyl sulfoxide are mixed evenly, stirred and diethanolamine is added at 130 r / min and 22℃, and the reaction is carried out for 2.5 h to obtain intermediate 2. Intermediate 2 and acetonitrile are mixed evenly, stirred and benzyl chloride and bromoethane are added at 120 r / min and 65℃, and the reaction is carried out for 3.5 h to obtain intermediate 3.

[0059] Step A3: Mix intermediate 3, acrylic acid and dimethylformamide evenly. Stir at 250 r / min and 22°C, and add perfluorobutyl sulfonate and p-hydroxyanisole. Stir for 10 min, then heat to 80°C and react for 2.5 h. Then heat to 90°C and react for 2.5 h to obtain the modified monomer.

[0060] In step A1, the ratio of tridecafluorooctol, epichlorohydrin, and sodium hydroxide solution is 10 mmol:10 mmol:25 mL, the amount of boron trifluoride ether is 4% of the mass of tridecafluorooctol, and the mass fraction of sodium hydroxide solution is 25%.

[0061] In step A2, the molar ratio of the epoxy group on intermediate 1 to the secondary amine on diethanolamine is 1:1, the mass fraction of ZnCl2 solution is 7%, the amount of ZnCl2 solution used is 4% of the mass of diethanolamine, and the molar ratio of intermediate 2, acetonitrile, benzyl chloride and bromoethane is 1:1.5:1.5:1.

[0062] The molar ratio of the hydroxyl group on intermediate 3 and the carboxyl group on acrylic acid in step A3 is 1:1, the amount of perfluorobutylsulfonate ammonium is 4% of the mass of acrylic acid, and the amount of p-hydroxyanisole is 1% of the mass of acrylic acid.

[0063] The modified filler is prepared by the following steps:

[0064] Step B1: Mix hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol and ammonia water evenly. Stir at 250 r / min, 22℃, and pH 7, and add γ-glycidoxypropyltrimethoxysilane and tetraethyl orthosilicate. Heat to 60℃ and react for 5 h. Heat to 85℃, add nano-alumina, stir for 15 min, and age for 13 h to obtain pretreated silica.

[0065] Step B2: Disperse carbon black in ethanol, stir and add deionized water and 3-aminopropyltriethoxysilane at a speed of 250 r / min, a temperature of 70℃ and a pH of 4, and react for 9 h to obtain pretreated carbon black.

[0066] Step B3: Mix pretreated silica, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add pretreated carbon black at 30 r / min and 22℃, and react for 2.5 h to obtain composite filler. Mix composite filler, acrylic acid and ethanol evenly, stir and add concentrated sulfuric acid at 400 r / min and 85℃, and react for 2.5 h to obtain modified filler.

[0067] In step B1, the ratio of hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol, ammonia, and tetraethyl orthosilicate is 0.35 g: 100 mL: 60 mL: 2 mL: 1.80 g, the amount of γ-glycidoxypropyltrimethoxysilane is 3% of the mass of tetraethyl orthosilicate, and the amount of nano-alumina is 25% of the mass of tetraethyl orthosilicate.

[0068] The amount of 3-aminopropyltriethoxysilane used in step B2 is 6% of the mass of carbon black.

[0069] In step B3, the ratio of pretreated silica, pretreated carbon black, and ZnCl2 solution is 2.5g:1.7g:10mL, and the ZnCl2 solution has a mass fraction of 7%. The ratio of composite filler, acrylic acid, and concentrated sulfuric acid is 6.5g:10mL:2mL, and the concentrated sulfuric acid has a mass fraction of 95%.

[0070] Example 3, a method for preparing an antistatic coating for a running board, specifically includes the following steps:

[0071] Step S1: Mix the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, modified filler and deionized water evenly. Stir and add potassium persulfate at 200 r / min and 30℃ for 4 h. Then raise the temperature to 100℃ and continue to react for 2 h to prepare the composite emulsion.

[0072] Step S2: Weigh the following raw materials by weight: 120 parts of composite emulsion, 20 parts of dispersant, 10 parts of defoamer, 15 parts of stabilizer, 40 parts of zinc oxide, 20 parts of ultrafine aluminum silicate, 40 parts of titanium dioxide and 60 parts of deionized water. Mix the raw materials evenly to obtain an antistatic coating.

[0073] The weight ratio of the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, potassium persulfate, deionized water and modified filler in step S1 is 120:200:130:70:3:70:80.

[0074] The dispersant mentioned in step S2 is a mixture of ACUMER 9300, OROTAN 1124 and Dispes Ultra PA 4560 in a mass ratio of 1:1.2:1.4; the defoamer is DC62; the stabilizer is a mixture of Tinuvin 292, Tinuvin 1130 and Tinuvin 123 in a mass ratio of 1:1.4:1.3; the ultrafine aluminum silicate is aluminum silicate powder with an average particle size ≤1.5μm and whiteness ≥97%; and the titanium dioxide is a mixture of PA101, R-960, SR-237 and R706 in a mass ratio of 1:1.1:1.5:1.4.

[0075] The modified monomer is prepared by the following steps:

[0076] Step A1: Mix tridecylfluorooctyl alcohol, boron trifluoride ether and acetone evenly, stir and add epichlorohydrin at 200 r / min and 30°C, heat to 75°C and react for 8 h, add sodium hydroxide solution and react for 5 h to obtain intermediate 1.

[0077] Step A2: Mix intermediate 1, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add diethanolamine at 150 r / min and 25℃, and react for 3 h to obtain intermediate 2. Mix intermediate 2 and acetonitrile evenly, stir and add benzyl chloride and bromoethane at 130 r / min and 70℃, and react for 4 h to obtain intermediate 3.

[0078] Step A3: Mix intermediate 3, acrylic acid and dimethylformamide evenly. Stir at 300 r / min and 25°C, and add perfluorobutyl sulfonate ammonium and p-hydroxyanisole. Stir for 10 min, then heat to 80°C and react for 3 h. Then heat to 90°C and react for 3 h to obtain the modified monomer.

[0079] In step A1, the ratio of tridecafluorooctol, epichlorohydrin, and sodium hydroxide solution is 10 mmol:10 mmol:25 mL, the amount of boron trifluoride ether is 5% of the mass of tridecafluorooctol, and the mass fraction of sodium hydroxide solution is 25%.

[0080] In step A2, the molar ratio of the epoxy group on intermediate 1 to the secondary amine on diethanolamine is 1:1, the mass fraction of ZnCl2 solution is 10%, the amount of ZnCl2 solution used is 5% of the mass of diethanolamine, and the molar ratio of intermediate 2, acetonitrile, benzyl chloride and bromoethane is 1:1.5:1.5:1.

[0081] In step A3, the molar ratio of the hydroxyl group on intermediate 3 to the carboxyl group on acrylic acid is 1:1, the amount of perfluorobutylsulfonate ammonium is 5% of the mass of acrylic acid, and the amount of p-hydroxyanisole is 1% of the mass of acrylic acid.

[0082] The modified filler is prepared by the following steps:

[0083] Step B1: Mix hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol and ammonia water evenly. Stir at 250 r / min, 25℃, and pH 8, and add γ-glycidoxypropyltrimethoxysilane and tetraethyl orthosilicate. Heat to 65℃ and react for 6 h. Heat to 90℃, add nano-alumina, stir for 20 min, and age for 15 h to obtain pretreated silica.

[0084] Step B2: Disperse carbon black in ethanol, stir and add deionized water and 3-aminopropyltriethoxysilane at a speed of 300 r / min, a temperature of 80℃ and a pH of 5, and react for 10 h to obtain pretreated carbon black.

[0085] Step B3: Mix pretreated silica, ZnCl2 solution and dimethyl sulfoxide evenly, stir and add pretreated carbon black at 150 r / min and 25℃, and react for 3 h to obtain composite filler. Then, stir the composite filler, acrylic acid and ethanol at 500 r / min and 90℃ and add concentrated sulfuric acid, and react for 3 h to obtain modified filler.

[0086] In step B1, the ratio of hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol, ammonia, and tetraethyl orthosilicate is 0.35 g: 100 mL: 60 mL: 2 mL: 1.80 g, the amount of γ-glycidoxypropyltrimethoxysilane is 5% of the mass of tetraethyl orthosilicate, and the amount of nano-alumina is 35% of the mass of tetraethyl orthosilicate.

[0087] The amount of 3-aminopropyltriethoxysilane used in step B2 is 10% of the mass of carbon black.

[0088] In step B3, the ratio of pretreated silica, pretreated carbon black, and ZnCl2 solution is 2.5g:1.7g:10mL, the ZnCl2 solution has a mass fraction of 10%, and the ratio of composite filler, acrylic acid, and concentrated sulfuric acid is 6.5g:10mL:2mL, the concentrated sulfuric acid has a mass fraction of 95%.

[0089] Comparative Example 1: This comparative example does not include nano-alumina compared to Example 1, but the other steps are the same.

[0090] Comparative Example 2: This comparative example uses carbon black instead of pretreated carbon black, but the other steps are the same as in Example 1.

[0091] Comparative Example 3: This comparative example is the same as Example 1, except that octanol is used instead of tridecylfluorooctol.

[0092] The antistatic coatings prepared in Examples 1-3 and Comparative Examples 1-3 were tested for abrasion resistance according to GB / T23988-2009. The test results are shown in Table 2. The thickness of the sample coating was 45 μm, and standard quartz sand was used as the abrasive. The particle size requirements are shown in Table 1. The abrasive flow rate was controlled at 90 mL / s.

[0093] The antistatic coatings prepared in Examples 1-3 and Comparative Examples 1-3 were tested for resistance to perspiration corrosion according to GB / T30648.2-2015. The test results are shown in Table 2. The thickness of the sample coating was 45 μm, the substrate was a 0.8 mm thick steel plate conforming to GB / T9271, and the dimensions were 150 mm * 50 mm. The cut edges were sealed with aluminum foil. The samples were completely immersed in a 0.9% sodium chloride solution for 5 days.

[0094] Table 1

[0095]

[0096] Table 2

[0097]

[0098] As shown in Table 2, the antistatic coatings prepared in Examples 1-3 have an abrasion resistance of 4.08-4.18 L / μm. After soaking in 0.9% sodium chloride solution for 5 days, the coating film showed no significant change, indicating that the present invention has excellent abrasion resistance and resistance to sweat corrosion.

[0099] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing an antistatic coating for running boards, characterized in that: Specifically, the steps include the following: Step S1: Mix and stir the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, modified filler and deionized water, add potassium persulfate, and react to obtain a composite emulsion. Step S2: Weigh the following raw materials in parts by weight: 100-120 parts of composite emulsion, 10-20 parts of dispersant, 5-10 parts of defoamer, 10-15 parts of stabilizer, 30-40 parts of zinc oxide, 10-20 parts of ultrafine aluminum silicate, 30-40 parts of titanium dioxide and 40-60 parts of deionized water. Mix the raw materials evenly to obtain an antistatic coating. The weight ratio of the modified monomer, methyl acrylate, methyl methacrylate, glycidyl methacrylate, potassium persulfate, deionized water and modified filler in step S1 is 100-120:180-200:110-130:50-70:1-3:55-70:60-80. in: The modified monomer is prepared by the following steps: Step A1: Mix tridecafluorooctyl alcohol, boron trifluoride ether and acetone and add epichlorohydrin. After heating and reacting, add sodium hydroxide solution and continue the reaction to obtain intermediate 1. Step A2: Mix intermediate 1, ZnCl2 solution and dimethyl sulfoxide and stir, then add diethanolamine and react to obtain intermediate 2. Mix intermediate 2 and acetonitrile and stir, then add benzyl chloride and bromoethane and react to obtain intermediate 3. Step A3: Mix intermediate 3, acrylic acid and dimethylformamide, stir and add ammonium perfluorobutyl sulfonate and p-hydroxyanisole, and react to obtain the modified monomer; The modified filler is prepared by the following steps: Step B1: Mix and stir hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol and ammonia, add γ-glycidyl etheroxypropyltrimethoxysilane and tetraethyl orthosilicate, react, heat and add nano-alumina, stir and age to obtain pretreated silica. Step B2: Disperse carbon black in ethanol, stir and add deionized water and 3-aminopropyltriethoxysilane to react and obtain pretreated carbon black; Step B3: Mix and stir pretreated silica, ZnCl2 solution and dimethyl sulfoxide, add pretreated carbon black, and react to obtain composite filler. Mix and stir composite filler, ethanol and acrylic acid, add concentrated sulfuric acid, and react to obtain modified filler.

2. The method for preparing the antistatic coating for running boards according to claim 1, characterized in that: In step A1, the ratio of tridecafluorooctol, epichlorohydrin, and sodium hydroxide solution is 10 mmol:10 mmol:25 mL, the amount of boron trifluoride ether is 3-5% of the mass of tridecafluorooctol, and the mass fraction of sodium hydroxide solution is 25%.

3. The method for preparing the antistatic coating for running boards according to claim 1, characterized in that: In step A2, the molar ratio of the epoxy group on intermediate 1 to the secondary amine on diethanolamine is 1:1, the mass fraction of ZnCl2 solution is 5-10%, the amount of ZnCl2 solution used is 3-5% of the mass of diethanolamine, and the molar ratio of intermediate 2, acetonitrile, benzyl chloride and bromoethane is 1:1.5:1.5:

1.

4. The method for preparing the antistatic coating for running boards according to claim 1, characterized in that: In step A3, the molar ratio of the hydroxyl group on intermediate 3 to the carboxyl group on acrylic acid is 1:1, the amount of perfluorobutylsulfonate ammonium is 3-5% of the mass of acrylic acid, and the amount of p-hydroxyanisole is 1% of the mass of acrylic acid.

5. The method for preparing the antistatic coating for running boards according to claim 1, characterized in that: In step B1, the ratio of hexadecyltrimethylammonium bromide, deionized water, anhydrous ethanol, ammonia, and tetraethyl orthosilicate is 0.35g:100mL:60mL:2mL:1.80g. The amount of γ-glycidoxypropyltrimethoxysilane is 1-5% of the mass of tetraethyl orthosilicate, and the amount of nano-alumina is 20-35% of the mass of tetraethyl orthosilicate.

6. The method for preparing the antistatic coating for running boards according to claim 1, characterized in that: The amount of 3-aminopropyltriethoxysilane used in step B2 is 5-10% of the mass of carbon black.

7. The method for preparing the antistatic coating for running boards according to claim 1, characterized in that: In step B3, the ratio of pretreated silica, pretreated carbon black, and ZnCl2 solution is 2.5g:1.7g:10mL, the mass fraction of ZnCl2 solution is 5-10%, and the ratio of composite filler, acrylic acid, and concentrated sulfuric acid is 6.5g:10mL:2mL, the mass fraction of concentrated sulfuric acid is 95%.

8. An antistatic coating for running boards, characterized in that: It is prepared according to any one of claims 1-7.

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