Coating composition for pavement marking and preparation method thereof

Abstract

The invention discloses a coating composition for pavement marking and a preparation method thereof, belongs to the technical field of coating production, and aims to solve the technical problem that the fluorescence property and wear resistance of pavement coatings in the prior art need to be further improved. The whitening polyacrylic resin is prepared from the following raw materials in parts by weight: 40 to 60 parts of whitening polyacrylic resin, 20 to 30 parts of functional filler and 6 to 12 parts of auxiliary materials, a phosphor is subjected to surface modification to enhance the water resistance and the compatibility with organic materials, and after the phosphor is used as a cross-linking agent to react with whitening polyacrylate, the warning effect of the phosphor at night is enhanced through synergistic cooperation with the high light reflection performance of the whitening polyacrylate. The surface of the functional filler is modified with a transparent material, so that the permeation performance of ultraviolet rays in the material is enhanced, the absorption performance of a phosphor and an ultraviolet initiator to the ultraviolet rays is improved, and finally the coating composition is prepared.

Description

Technical Field

[0001] The invention relates to the technical field of coating production, and in particular to a coating composition for road markings and a preparation method thereof. Background Art

[0002] Pavement marking paints have undergone significant technological evolution since their early applications, mainly to improve their performance in terms of fluorescence performance and durability. Initially, pavement markings used asphalt-based or oil-based paints, which were easy to apply but had poor visibility at night or in bad weather conditions. To improve this situation, the R&D team introduced tiny glass beads that can reflect vehicle lights, significantly improving visibility at night. More recently, the application of nanotechnology and environmentally friendly materials represents the latest development direction of pavement marking paint technology. These materials not only improve the fluorescence characteristics and durability of the coating, but also help reduce the environmental burden. This series of technological advances continues to improve the functionality of pavement markings, ensuring driving safety and efficient road use.

[0003] Prior art CN117887316B discloses an anti-skid road marking paint and a preparation method thereof, belonging to the technical field of paint preparation, comprising the following components in parts by weight: 40-50 parts of photocurable resin, 5-10 parts of luminous hollow glass microspheres, 15-20 parts of elastic filler I, 15-20 parts of elastic filler II, 0.1-2 parts of pigment, and 1-5 parts of photoinitiator. The preparation method is: silane coupling agent, ethanol, and luminous powder are mixed and stirred evenly, and sprayed on the surface of etched hollow glass microspheres to obtain luminous hollow glass microspheres, the photoinitiator and the photocurable resin are mixed evenly, and the luminous hollow glass microspheres, elastic filler I, elastic filler II, and pigment are sequentially added to the photocurable resin system to obtain the road marking paint; the above patent content is to add luminous hollow glass microspheres, elastic filler I and elastic filler II to the road marking paint to solve the problem of insufficient visibility and insufficient anti-skid performance of the road marking paint in bad weather and dark light environment.

[0004] However, the above patent content is to etch the surface of the glass microsphere crystal and then graft luminescent powder on its surface to give the glass microsphere surface fluorescent properties, thereby overcoming the problem of insufficient visibility of road marking paint in bad weather and dim light environments. However, the luminescent powder selected in the above patent content is an aluminate long afterglow luminescent material, which has poor water resistance, resulting in the fluorescence performance of the paint laid on outdoor roads to be easily reduced. After hydrolysis, the aluminate is prone to structural changes, thereby destroying the paint structure, and further resulting in the wear resistance of the material needs to be further improved.

[0005] In view of the technical defects in this aspect, a solution is now proposed. Summary of the invention

[0006] The object of the present invention is to provide a coating composition for road marking and a preparation method thereof, so as to solve the technical problem that the fluorescence performance and wear resistance of road coatings in the prior art need to be further improved.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] A coating composition for road markings, comprising the following raw materials in parts by weight: 40-60 parts of whitening polyacrylic acid resin, 20-30 parts of functional filler and 6-12 parts of auxiliary materials;

[0009] The preparation method of the functionalized filler comprises the following steps:

[0010] A1. Add self-repairing filler, methyl 4-cycloocten-1-yl carbonate, triethylamine and N,N-dimethylformamide into a reactor, raise the temperature of the reactor to 60-80°C, keep the temperature for 40-60 minutes, and post-treat to obtain a functionalized filler precursor;

[0011] The reaction principle for preparing the functional filler precursor is as follows: under the catalysis of alkaline conditions and heating conditions, the epoxy groups on the surface of the self-healing filler undergo a ring-opening reaction to generate free radicals, which react with the carboxyl groups on methyl carbonate-4-cycloocten-1-yl ester, thereby making methyl carbonate-4-cycloocten-1-yl ester evenly dispersed on the surface of the self-healing filler, and finally preparing the functional filler precursor.

[0012] A2. Add the functional filler precursor and N,N-dimethylformamide into the ultrasonic instrument, set the frequency of the ultrasonic instrument to 10-20kHz, increase the temperature to 60-80°C, add azobisisobutyronitrile into the ultrasonic instrument, keep the temperature for 1-2h, and post-treat to obtain the functional filler.

[0013] The reaction principle for preparing the functionalized filler is as follows: a large number of double bond structures introduced by vinyltrimethoxysilane exist on the surface of the functionalized filler precursor, which react with the double bonds on methyl carbonate-4-cycloocten-1-yl ester on the surface of the functionalized filler precursor under the catalysis of a free radical initiator and heating conditions to generate free radicals, and a modified layer with a large number of carbonates is formed on the surface of the functionalized filler precursor through continuous polymerization to obtain a functionalized filler.

[0014] Furthermore, in step A1, the amount ratio of self-healing filler, methyl 4-cycloocten-1-yl carbonate, triethylamine and N,N-dimethylformamide is 8-10g:4-5g:2-3g:60-70mL, and the post-treatment includes: after the reaction is completed, filtering the reaction liquid, collecting the filter cake, washing it with anhydrous ethanol and deionized water for 3-5 times, and placing the filter cake in a drying oven at a temperature of 60°C for vacuum drying to obtain a functionalized filler precursor.

[0015] Furthermore, in step A2, the dosage ratio of the functionalized filler precursor, N,N-dimethylformamide and azobisisobutyronitrile is 4-5g:15-20mL:0.1-0.2g, and the post-treatment includes: after the reaction is completed, the reaction liquid is filtered, the filter cake is collected, and after washing with anhydrous ethanol and deionized water for 3-5 times, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried to obtain the functionalized filler.

[0016] Furthermore, the auxiliary materials include the following raw materials in parts by weight: 3-5 parts of titanium dioxide, 1-2 parts of leveling agent, 1-2 parts of dispersant and 1-3 parts of ultraviolet absorber; the leveling agent is one or more of dimethyl silicone oil, ethoxylated silicone oil and polyether modified silicone oil; the dispersant is one or more of sodium polycarboxylate, ammonium polyphosphate and hydroxyethyl cellulose; the ultraviolet absorber is one or more of 2,4-dihydroxybenzophenone, 2,4,6-tris[(2'-hydroxy-5'-methylphenyl)methyl]-1,3,5-triazine and 2-(2'-hydroxy-5'-methylphenyl)benzotriazole.

[0017] Furthermore, the preparation method of the self-repairing filler comprises the following steps:

[0018] B1, adding allyl methyl carbonate, triphenoxy vinyl silane, 4,4'-dimethoxybenzophenone and methyl orthosilicate into a reaction kettle and stirring for 5-10 minutes to obtain an oil phase solution;

[0019] B2, adding the oil phase solution into an ultrasonic emulsifier, and pouring sorbitan oleate and deionized water into the ultrasonic emulsifier, setting the frequency of the ultrasonic emulsifier to 20-40kHz, and ultrasonicating for 20-30min at room temperature to obtain a mixed emulsion;

[0020] B3. Add the mixed emulsion into the reactor and stir. Add saturated sodium hydroxide solution to the reactor to adjust the system pH to 8-10. Raise the temperature of the reactor to 40-50°C. After keeping warm for 2-3 hours, lower the temperature of the reactor to 0-5°C. Add the modifier twice in equal amounts. After both additions, keep warm for 1-2 hours. Post-treat to obtain the self-healing filler.

[0021] The reaction principle for preparing self-healing fillers is as follows: after deionized water and surfactants are poured into the oil phase solution and stirred at high speed, a water-in-oil structure is generated. After adjusting the pH of the system, the methyl orthosilicate in the oil phase solution is hydrolyzed at the water-oil interface and finally hydrolyzed on the surface of the oil phase droplets to produce a stable cross-linked structure. After adding a modifier, a stable dense structure and modified functional groups are further formed on the capsule surface, and finally a self-healing filler is prepared.

[0022] Furthermore, in step B1, the amount ratio of allyl methyl carbonate, triphenoxyvinyl silane, 4,4'-dimethoxybenzophenone and methyl orthosilicate is 5-8g:3-5g:0.3-0.5g:20-30mL; in step B2, the amount ratio of oil phase solution, sorbitan oleate and deionized water is 10-12mL:3-4mL:40-60mL.

[0023] In step B3, the amount ratio of the mixed emulsion and the modifier is 40mL:3-5mL, and the modifier is a mixture of vinyltrimethoxysilane and 3-(2,3-epoxypropoxy)propyltrimethoxysilane in a volume ratio of 1mL:1-1.5mL. The post-treatment includes: after the reaction is completed, the reaction liquid is filtered, the filter cake is collected, and it is washed 3-5 times with anhydrous ethanol and deionized water, and then the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried until the filter cake has a constant weight to obtain a self-healing filler.

[0024] Furthermore, the preparation method of the whitening polyacrylic acid resin is as follows: acrylic acid, 1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 1-allyloxy-2,3-propylene oxide, azobisisobutyronitrile and dimethyl sulfoxide are added to a reactor and stirred, the temperature of the reactor is increased to 60-80°C, and after being stirred for 1-2 hours, an afterglow crosslinking agent and benzoic acid are added to the reactor, and the reaction is kept warm for 20-30 minutes, and the whitening polyacrylic acid resin is obtained by post-treatment.

[0025] The reaction equation for preparing whitening polyacrylic acid resin is:

[0026]

[0027] Where: ; In the formula, ” indicates the active cross-linking site of the organic chain segment.

[0028] The reaction principle for preparing the whitening polyacrylic acid resin is as follows: under the catalysis of a free radical initiator and heating conditions, the double bonds on acrylic acid, 1,2-bis(5-methyl-2-benzoxazolyl)-ethylene and 1-allyloxy-2,3-propylene oxide undergo a free radical addition reaction, and a long-chain polypropylene segment is prepared by continuous polymerization of the double bonds. Under the catalysis of benzoic acid, the epoxy groups on the segment undergo ring opening and react with the hydroxyl groups on the afterglow crosslinking agent, and finally the whitening polyacrylic acid resin is prepared.

[0029] Further, the stirring rate of the reactor is 80-120rpm, the amount ratio of acrylic acid, 1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 1-allyloxy-2,3-propylene oxide, azobisisobutyronitrile, dimethyl sulfoxide, afterglow crosslinking agent and benzoic acid is 8-10g:2-3g:4-5g:0.3-0.5g:45-60mL:2-3g:0.8-1g, and the post-treatment includes: after the reaction is completed, the reactor is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80-100°C, and the whitening polyacrylic acid resin is obtained by reduced pressure distillation until no liquid is extracted.

[0030] Further, the preparation method of the afterglow crosslinking agent comprises the following steps:

[0031] C1. Add 3-(methacryloyloxy)propyltrimethoxysilane and anhydrous ethanol to a reactor, stir at room temperature for 15 minutes, then add strontium aluminate, seal the reactor, heat in a water bath at 50-60° C. for 2-4 hours, and perform post-treatment to obtain modified strontium aluminate;

[0032] The reaction principle for preparing modified strontium aluminate is as follows: under hydrothermal conditions, the siloxane segments on 3-(methacryloyloxy)propyltrimethoxysilane are hydrolyzed to form a silanol structure, which is cross-linked with the hydroxyl groups on strontium aluminate, and finally a coating layer is formed on the surface of the aluminate to obtain modified strontium aluminate.

[0033] C2. Place the modified strontium aluminate in a reactor filled with (hydroxymethyl) acrylate / ethylene glycol solution, raise the temperature of the reactor to 60-80°C, and dropwise add potassium persulfate while stirring until a flocculent precipitate is produced, and post-treat to obtain an afterglow crosslinking agent.

[0034] The reaction principle for preparing the afterglow crosslinking agent is as follows: under the catalysis of a free radical initiator and heating conditions, the double bonds on the surface of the modified strontium aluminate react, and eventually a poly(hydroxymethyl)acrylate coating layer is formed on the surface of the modified strontium aluminate. When precipitation occurs, it indicates that the self-polymerization of poly(hydroxymethyl)acrylate exists in the reaction, which reduces the dispersibility of the material. Therefore, the reaction process is terminated, and the afterglow crosslinking agent is obtained by post-processing.

[0035] Furthermore, in step C1, the stirring rate of the reactor is 80-120rpm, the usage ratio of 3-(methacryloyloxy)propyltrimethoxysilane, anhydrous ethanol and strontium aluminate is 4-5g:40-60mL:20-30g, and the post-treatment includes: after the reaction is completed, the reaction liquid is filtered, the filter cake is collected, and after washing with anhydrous ethanol for 3-5 times, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried until the filter cake has a constant weight to obtain modified strontium aluminate.

[0036] Furthermore, in step C2, the dosage ratio of modified strontium aluminate, (hydroxymethyl) acrylate / ethylene glycol solution and potassium persulfate is 4-5g:20-25mL:0.3-0.5g, and the (hydroxymethyl) acrylate / ethylene glycol solution is obtained by mixing (hydroxymethyl) acrylate and ethylene glycol in a dosage ratio of 1mL:3-5mL. The post-treatment includes: after the reaction is completed, filtering the reaction liquid, collecting the filter cake, washing it with anhydrous ethanol and deionized water for 3-5 times, and placing the filter cake in a drying oven at a temperature of 60°C and vacuum drying it until the filter cake has a constant weight to obtain an afterglow crosslinking agent.

[0037] The present invention also provides a method for preparing a coating composition for road markings, comprising the following steps: adding whitening polyacrylic resin, functionalized repair filler, titanium dioxide, leveling agent, dispersant and ultraviolet absorber into a reaction kettle and mixing them evenly, and passing through a 300-500 mesh sieve to obtain a coating composition.

[0038] The present invention has the following beneficial effects:

[0039] 1. The present invention enhances the water resistance and compatibility with organic materials by surface modification of the phosphor. The poly(hydroxymethyl)acrylate on its surface acts as a crosslinking agent to enhance the crosslinking of the whitening polyacrylate. The whitening polyacrylate also provides protection for the stability of the phosphor, and enhances the wear resistance of the material while overcoming the disadvantage of poor water resistance of strontium aluminate, thereby improving the water resistance of the material. After organic modification, the dispersion of strontium aluminate in the coating system is significantly improved, thereby improving the excitation stop brightness of the material and ensuring the warning function of the material at night. The warning function at night is enhanced by synergizing with the high reflective properties of the whitening polyacrylate, and the transparent material is modified on the surface of the functionalized filler to enhance the transmittance of ultraviolet rays inside the material, thereby improving the absorption of ultraviolet rays by the phosphor and the ultraviolet initiator, and finally preparing a coating composition.

[0040] 2. The present invention modifies the surface of the self-repairing filler with epoxy groups, which cross-link with the carboxyl groups on methyl carbonate-4-cyclooctene-1-yl ester, so that the carbonate is evenly dispersed on the self-repairing surface, and then forms a stable coating structure through self-polymerization and double bond polymerization on the surface of the self-repairing filler. Compared with direct solution polymerization, the self-polymerization reaction of methyl carbonate-4-cyclooctene-1-yl ester is inhibited, thereby significantly improving the dispersion ability of the functionalized filler, and the transparent polycarbonate component is dispersed inside the coating, which greatly improves the absorption capacity of strontium aluminate to ultraviolet rays, thereby enhancing the brightness after stopping excitation for 60 minutes. When the coating is damaged, the internal functionalized filler is broken, which promotes the activation of the photoinitiator inside the functionalized filler, and promotes the internal repair monomer to repair the gaps on the coating surface, thereby enhancing the wear resistance of the material, promoting the self-polymerization repair process of the coating product, and ensuring the improvement of the fluorescence performance of the coating product.

[0041] 3. After the whitening polyacrylate organic chain segment prepared by the present invention is modified with epoxy groups and fluorescent whitening groups, the epoxy groups improve the fluidity and wetting behavior of the coating on the substrate, which helps the coating to form a more uniform and tight covering layer, thereby improving the adhesion, and the three-membered ring structure of the epoxy group is highly reactive in the ring-opening reaction. When the epoxy group contacts the functional group on the surface of the substrate, a chemical reaction can occur through the formation of covalent bonds, thereby greatly improving the adhesion strength of the coating; the electrons of the fluorescent whitening group are excited to a higher energy level, and then when the electrons fall back to a low energy level, they release energy in the form of light with a longer wavelength. After releasing the blue light, the yellow or dark tone of the material itself is compensated, making the material look whiter and brighter, and in a lower light environment, the material appears brighter, which improves its overall visual appeal and ensures the eye-catching effect of the coating during the day and the warning effect at night. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] Example 1

[0044] This embodiment provides a method for preparing an afterglow crosslinking agent for a coating composition for road markings, comprising the following steps:

[0045] Step (1): Preparation of modified strontium aluminate

[0046] Add 400.0g 3-(methacryloyloxy)propyltrimethoxysilane and 4.0L anhydrous ethanol to the reactor, stir at room temperature for 15min, then add 2.0kg strontium aluminate, the stirring rate is 80rpm, seal the reactor and heat in a water bath at 50°C for 2h. After the reaction is completed, filter the reaction liquid, collect the filter cake, wash it with anhydrous ethanol three times, and place the filter cake in a drying oven at 60°C for vacuum drying until the filter cake has constant weight to obtain modified strontium aluminate.

[0047] Step (2), afterglow crosslinking agent

[0048] Weigh: 100.0 mL of (hydroxymethyl) acrylate and 300.0 mL of ethylene glycol are mixed to obtain a (hydroxymethyl) acrylate / ethylene glycol solution;

[0049] Weigh: 400.0g of modified strontium aluminate is placed in a reactor filled with 2.0L of (hydroxymethyl) acrylate / ethylene glycol solution, the temperature of the reactor is raised to 60°C, and 30.0g of potassium persulfate is added dropwise while stirring until a flocculent precipitate is produced. After the reaction is completed, the reaction liquid is filtered, and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 3 times, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried until the filter cake has a constant weight to obtain an afterglow crosslinking agent.

[0050] Example 2

[0051] This embodiment provides a method for preparing an afterglow crosslinking agent for a coating composition for road markings, comprising the following steps:

[0052] Step (1): Preparation of modified strontium aluminate

[0053] Add 500.0g3-(methacryloyloxy)propyltrimethoxysilane and 6.0L anhydrous ethanol to the reactor, stir at room temperature for 15min, then add 3.0kg strontium aluminate with a stirring rate of 120rpm. Seal the reactor and heat in a water bath at 60°C for 4h. After the reaction is completed, filter the reaction liquid and collect the filter cake. After washing it with anhydrous ethanol 5 times, place the filter cake in a drying oven at 60°C and vacuum dry it until the filter cake has constant weight to obtain modified strontium aluminate.

[0054] Step (2), afterglow crosslinking agent

[0055] Weigh: 100.0 mL of (hydroxymethyl) acrylate and 500.0 mL of ethylene glycol, and mix to obtain a (hydroxymethyl) acrylate / ethylene glycol solution;

[0056] Weigh: 500.0g of modified strontium aluminate is placed in a reactor filled with 2.5L of (hydroxymethyl) acrylate / ethylene glycol solution, the temperature of the reactor is raised to 80°C, and 50.0g of potassium persulfate is added dropwise while stirring until a flocculent precipitate is produced. After the reaction is completed, the reaction liquid is filtered, and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 5 times, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried until the filter cake has a constant weight to obtain an afterglow crosslinking agent.

[0057] Example 3

[0058] This embodiment provides a method for preparing an afterglow crosslinking agent for a coating composition for road markings, comprising the following steps:

[0059] Step (1): Preparation of modified strontium aluminate

[0060] Add 450.0g 3-(methacryloyloxy)propyltrimethoxysilane and 5.0L anhydrous ethanol to the reactor, stir at room temperature for 15 minutes, then add 2.5kg strontium aluminate with a stirring rate of 100rpm. After sealing the reactor, heat in a water bath at 55°C for 3h. After the reaction is completed, filter the reaction liquid, collect the filter cake, wash it with anhydrous ethanol 4 times, and place the filter cake in a drying oven at 60°C for vacuum drying until the filter cake has constant weight to obtain modified strontium aluminate.

[0061] Step (2), afterglow crosslinking agent

[0062] Weigh: 100.0 mL of (hydroxymethyl) acrylate and 400.0 mL of ethylene glycol are mixed to obtain a (hydroxymethyl) acrylate / ethylene glycol solution;

[0063] Weigh: 450.0g of modified strontium aluminate is placed in a reactor filled with 2.1L of (hydroxymethyl) acrylate / ethylene glycol solution, the temperature of the reactor is raised to 70°C, and 40.0g of potassium persulfate is added dropwise while stirring until a flocculent precipitate is produced. After the reaction is completed, the reaction liquid is filtered, and the filter cake is collected. After washing 4 times with anhydrous ethanol and deionized water, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried until the filter cake has a constant weight to obtain an afterglow crosslinking agent.

[0064] Example 4

[0065] This embodiment provides a method for preparing a functionalized filler for a coating composition for road markings, and a method for preparing a self-repairing filler for preparing the functionalized filler for a road marking coating composition, comprising the following steps:

[0066] Step ①: Preparation of oil phase solution

[0067] Weigh 500.0 g of allyl methyl carbonate, 300.0 g of triphenoxy vinyl silane, 30.0 g of 4,4'-dimethoxybenzophenone and 2.0 L of methyl orthosilicate, add them into a reaction kettle and stir for 5 minutes to obtain an oil phase solution.

[0068] Step ②: preparing mixed emulsion

[0069] Weigh: 1.0L of oil phase solution is added into an ultrasonic emulsifier, and 300.0mL of sorbitan oleate and 4.0L of deionized water are poured into the ultrasonic emulsifier. The frequency of the ultrasonic emulsifier is set to 20kHz, and ultrasonication is performed at room temperature for 20 minutes to obtain a mixed emulsion.

[0070] Step ③: Preparation of self-repairing filler

[0071] Weigh: 100.0 mL of vinyl trimethoxy silane and 100.0 mL of 3-(2,3-epoxypropoxy)propyl trimethoxy silane to obtain a modifier;

[0072] Weigh: 4.0L of mixed emulsion was added into the reactor and stirred. Saturated sodium hydroxide solution was added dropwise into the reactor to adjust the pH value of the system to 8. The temperature of the reactor was raised to 40°C. After keeping warm for 2 hours, the temperature of the reactor was lowered to 5°C. 300.0mL of modifier was added twice in equal amounts. After each addition, the reaction was kept warm for 1 hour. After the reaction was completed, the reaction liquid was filtered and the filter cake was collected. After washing with anhydrous ethanol and deionized water for 3 times, the filter cake was placed in a drying oven at 60°C and vacuum dried until the filter cake had a constant weight to obtain a self-healing filler.

[0073] Example 5

[0074] This embodiment provides a method for preparing a functionalized filler for a coating composition for road markings, and a method for preparing a self-repairing filler for preparing the functionalized filler for a road marking coating composition, comprising the following steps:

[0075] Step ①: Preparation of oil phase solution

[0076] Weigh 800.0 g of allyl methyl carbonate, 500.0 g of triphenoxy vinyl silane, 50.0 g of 4,4'-dimethoxybenzophenone and 3.0 L of methyl orthosilicate, add them into a reaction kettle and stir for 10 minutes to obtain an oil phase solution.

[0077] Step ②: preparing mixed emulsion

[0078] Weigh: 1.2L of oil phase solution is added into an ultrasonic emulsifier, and 400.0mL of sorbitan oleate and 6.0L of deionized water are poured into the ultrasonic emulsifier. The frequency of the ultrasonic emulsifier is set to 40kHz, and ultrasonication is performed at room temperature for 30 minutes to obtain a mixed emulsion.

[0079] Step ③: Preparation of self-repairing filler

[0080] Weigh: 100.0 mL of vinyl trimethoxy silane and 150.0 mL of 3-(2,3-epoxypropoxy)propyl trimethoxy silane and mix to obtain a modifier;

[0081] Weigh: 4.0L of mixed emulsion was added into the reactor and stirred. Saturated sodium hydroxide solution was added dropwise into the reactor to adjust the pH of the system to 10. The temperature of the reactor was raised to 50°C. After keeping warm for 3 hours, the temperature of the reactor was lowered to 0°C. 500.0mL of modifier was added twice in equal amounts. After each addition, the reaction was kept warm for 2 hours. After the reaction was completed, the reaction liquid was filtered and the filter cake was collected. After washing with anhydrous ethanol and deionized water for 5 times, the filter cake was placed in a drying oven at 60°C and vacuum dried until the filter cake had a constant weight to obtain a self-healing filler.

[0082] Example 6

[0083] This embodiment provides a method for preparing a functionalized filler for a coating composition for road markings, and a method for preparing a self-repairing filler for preparing the functionalized filler for a road marking coating composition, comprising the following steps:

[0084] Step ①: Preparation of oil phase solution

[0085] Weigh 600.0 g of allyl methyl carbonate, 350.0 g of triphenoxy vinyl silane, 40.0 g of 4,4'-dimethoxybenzophenone and 2.5 L of methyl orthosilicate into a reaction kettle and stir for 8 minutes to obtain an oil phase solution.

[0086] Step ②: preparing mixed emulsion

[0087] Weigh: 1.0L of oil phase solution is added into an ultrasonic emulsifier, and 350.0mL of sorbitan oleate and 5.0L of deionized water are poured into the ultrasonic emulsifier. The frequency of the ultrasonic emulsifier is set to 30kHz, and ultrasonication is performed at room temperature for 25 minutes to obtain a mixed emulsion.

[0088] Step ③: Preparation of self-repairing filler

[0089] Weigh: 100.0 mL of vinyl trimethoxy silane and 120.0 mL of 3-(2,3-epoxypropoxy)propyl trimethoxy silane and mix to obtain a modifier;

[0090] Weigh: 4.0L of mixed emulsion was added into the reactor and stirred. Saturated sodium hydroxide solution was added dropwise into the reactor to adjust the pH value of the system to 9. The temperature of the reactor was raised to 45°C. After keeping warm for 2 hours, the temperature of the reactor was lowered to 3°C. 400.0mL of modifier was added twice in equal amounts. After both additions, the reaction was kept warm for 2 hours. After the reaction was completed, the reaction liquid was filtered and the filter cake was collected. After washing with anhydrous ethanol and deionized water for 4 times, the filter cake was placed in a drying oven at 60°C and vacuum dried until the filter cake had a constant weight to obtain a self-healing filler.

[0091] Example 7

[0092] This embodiment provides a method for preparing a functionalized filler for a coating composition for road markings, comprising the following steps:

[0093] Step I: Preparation of functionalized filler precursor

[0094] Weigh: 800.0g of the self-healing filler prepared in Example 4, 400.0g of methyl carbonate-4-cycloocten-1-yl ester, 200.0g of triethylamine and 6.0LN,N-dimethylformamide, and add them into the reactor. The temperature of the reactor is raised to 60°C and the reaction is kept warm for 40 minutes. After the reaction is completed, the reaction liquid is filtered and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 3 times, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried to obtain a functionalized filler precursor.

[0095] Step II: Preparation of functionalized filler

[0096] Weigh: 400.0g of functional filler precursor and 1.5LN,N-dimethylformamide are added to the ultrasonic instrument. The frequency of the ultrasonic instrument is set to 10kHz. After the temperature is raised to 60°C, 10.0g of azobisisobutyronitrile is added to the ultrasonic instrument. The reaction is kept warm for 1h. After the reaction is completed, the reaction liquid is filtered and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 3 times, the filter cake is placed in a drying oven at 60°C for vacuum drying to obtain a functional filler.

[0097] Example 8

[0098] This embodiment provides a method for preparing a functionalized filler for a coating composition for road markings, comprising the following steps:

[0099] Step I: Preparation of functionalized filler precursor

[0100] Weigh: 1000.0g of the self-healing filler prepared in Example 5, 500.0g of methyl carbonate-4-cycloocten-1-yl ester, 300.0g of triethylamine and 7.0LN,N-dimethylformamide, and add them into the reactor. The temperature of the reactor is raised to 80°C and the reaction is kept warm for 60 minutes. After the reaction is completed, the reaction liquid is filtered and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 5 times, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried to obtain a functionalized filler precursor.

[0101] Step II: Preparation of functionalized filler

[0102] Weigh: 500.0g of functionalized filler precursor and 2.0LN,N-dimethylformamide are added into the ultrasonic instrument. The frequency of the ultrasonic instrument is set to 20kHz. After the temperature is raised to 80°C, 20.0g of azobisisobutyronitrile is added into the ultrasonic instrument. The reaction is kept warm for 2h. After the reaction is completed, the reaction liquid is filtered and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 5 times, the filter cake is placed in a drying oven at 60°C for vacuum drying to obtain a functionalized filler.

[0103] Example 9

[0104] This embodiment provides a method for preparing a functionalized filler for a coating composition for road markings, comprising the following steps:

[0105] Step I: Preparation of functionalized filler precursor

[0106] Weigh: 900.0g of the self-healing filler prepared in Example 6, 500.0g of methyl carbonate-4-cycloocten-1-yl ester, 250.0g of triethylamine and 6.5LN,N-dimethylformamide, and add them into the reactor. The temperature of the reactor is raised to 70°C and the reaction is kept warm for 50 minutes. After the reaction is completed, the reaction liquid is filtered and the filter cake is collected. After washing 4 times with anhydrous ethanol and deionized water, the filter cake is placed in a drying oven at a temperature of 60°C and vacuum dried to obtain a functionalized filler precursor.

[0107] Step II: Preparation of functionalized filler

[0108] Weigh: 450.0g of functionalized filler precursor and 1.8L N,N-dimethylformamide are added to the ultrasonic instrument. The frequency of the ultrasonic instrument is set to 15kHz. After the temperature is raised to 70°C, 15.0g of azobisisobutyronitrile is added to the ultrasonic instrument. The reaction is kept warm for 1h. After the reaction is completed, the reaction liquid is filtered and the filter cake is collected. After washing with anhydrous ethanol and deionized water for 4 times, the filter cake is placed in a drying oven at 60°C for vacuum drying to obtain a functional filler.

[0109] Example 10

[0110] This embodiment provides a method for preparing a coating composition for road markings, comprising the following steps:

[0111] Step 1: Preparation of whitening polyacrylic acid resin

[0112] Weigh: 800.0g acrylic acid, 200.0g1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 400.0g1-allyloxy-2,3-propylene oxide, 30.0g azobisisobutyronitrile and 4.5L dimethyl sulfoxide, add to a reactor and stir, the stirring rate is 80rpm, the temperature of the reactor is raised to 60°C, after stirring for 4h, 200.0g of the afterglow crosslinking agent prepared in Example 1 and 80.0g of benzoic acid are added to the reactor, and the reaction is kept warm for 20min. After the reaction is completed, the reactor is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 80°C, and distilled under reduced pressure until no liquid is produced to obtain a whitening polyacrylic acid resin.

[0113] Step 2: Preparation of whitening polyacrylic acid resin

[0114] Weigh: 4.0 kg of whitening polyacrylic acid resin, 2.0 kg of the functional filler prepared in Example 7, 300.0 g of titanium dioxide, 100.0 g of ethoxylated silicone oil, 100.0 g of sodium polycarboxylate and 100.0 g of 2,4-dihydroxybenzophenone, add into a reaction kettle, mix evenly, and pass through a 500-mesh sieve to obtain a coating composition.

[0115] Embodiment 11

[0116] This embodiment provides a method for preparing a coating composition for road markings, comprising the following steps:

[0117] Step 1: Preparation of whitening polyacrylic acid resin

[0118] Weigh: 1000.0g acrylic acid, 300.0g1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 500.0g1-allyloxy-2,3-propylene oxide, 50.0g azobisisobutyronitrile and 6.0L dimethyl sulfoxide, add to a reactor and stir, the stirring rate is 120rpm, the temperature of the reactor is raised to 80°C, after stirring for 2h, 300.0g of the afterglow crosslinking agent prepared in Example 2 and 100.0g of benzoic acid are added to the reactor, and the reaction is kept warm for 30min. After the reaction is completed, the reactor is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 100°C, and distilled under reduced pressure until no liquid is produced to obtain a whitening polyacrylic acid resin.

[0119] Step 2: Preparation of whitening polyacrylic acid resin

[0120] Weigh: 6.0 kg of whitening polyacrylic acid resin, 3.0 kg of the functional filler prepared in Example 8, 500.0 g of titanium dioxide, 200.0 g of ethoxylated silicone oil, 200.0 g of sodium polycarboxylate and 300.0 g of 2,4-dihydroxybenzophenone, add into a reaction kettle, mix evenly, and pass through a 500-mesh sieve to obtain a coating composition.

[0121] Example 12

[0122] This embodiment provides a method for preparing a coating composition for road markings, comprising the following steps:

[0123] Step 1: Preparation of whitening polyacrylic acid resin

[0124] Weigh: 900.0g acrylic acid, 250.0g1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 450.0g1-allyloxy-2,3-propylene oxide, 40.0g azobisisobutyronitrile and 5.4L dimethyl sulfoxide, add to a reactor and stir, the stirring rate is 100rpm, the temperature of the reactor is raised to 70°C, after stirring for 1h, 250.0g of the afterglow crosslinking agent prepared in Example 3 and 90.0g of benzoic acid are added to the reactor, and the reaction is kept warm for 24min. After the reaction is completed, the reactor is cooled to room temperature, the reaction solution is added to a rotary evaporator with a water bath temperature of 90°C, and distilled under reduced pressure until no liquid is produced to obtain a whitening polyacrylic acid resin.

[0125] Step 2: Preparation of whitening polyacrylic acid resin

[0126] Weigh: 5.0 kg of whitening polyacrylic acid resin, 2.5 kg of the functional filler prepared in Example 9, 400.0 g of titanium dioxide, 150.0 g of ethoxylated silicone oil, 150.0 g of sodium polycarboxylate and 200.0 g of 2,4-dihydroxybenzophenone, add into a reaction kettle, mix evenly, and pass through a 400-mesh sieve to obtain a coating composition.

[0127] Comparative Example 1

[0128] The difference between this comparative example and Example 12 is that step (2) is omitted during the preparation of the afterglow crosslinking agent used.

[0129] Comparative Example 2

[0130] The difference between this comparative example and Example 12 is that in step 1, an equal amount of the self-repairing filler prepared in Example 6 is used to replace the functional filler.

[0131] Comparative Example 3

[0132] The difference between this comparative example and Example 12 is that in step 1, acrylic acid is used in equal amounts to replace 1,2-bis(5-methyl-2-benzoxazolyl)-ethylene and 1-allyloxy-2,3-propylene oxide.

[0133] Performance Testing:

[0134] The adhesion, abrasion resistance, water resistance and retroreflection coefficient of the coating compositions prepared in Examples 10-12 and Comparative Examples 1-3 were measured with reference to the standard GA / T 298-2001 "Road Marking Paints";

[0135] The brightness of the coating composition coating products prepared in Examples 10-12 and Comparative Examples 1-3 after stopping excitation for 60 minutes was tested with reference to the standard DB33 / T 2204-2019 "Test Procedure for Self-luminous Traffic Signs";

[0136] The self-repairing time of the coating composition coating products prepared in Examples 1-3 and Comparative Examples 1-3 was tested with reference to the standard HG / T 5675-2020 "Self-repairing hardened film of optical functional film". The specific data are shown in Table 1.

[0137] Table 1- Performance data checklist for each sample

[0138]

[0139] Data Analysis:

[0140] Comparative analysis of the data in Table 1 above shows that the coating composition prepared by the present invention has an adhesion of Grade 2, an abrasion loss of 19 mg, and a retroreflection coefficient of 264 mcd·(lx·m 2 ) -1, the brightness after stopping the excitation for 60 minutes is 271mcd·m -2 And the self-repair time is 7 minutes;

[0141] By comparing the data of Example 12 and Comparative Example 1, it can be found that the wear resistance, water resistance and brightness of the coating composition coated product prepared in Example 12 after stopping excitation for 60 minutes are significantly improved, indicating that the compatibility of strontium aluminate and whitening polyacrylate is improved after the surface coating of acrylic acid (hydroxymethyl) ester, and the acrylic acid (hydroxymethyl) ester on its surface acts as a cross-linking agent to enhance the cross-linking property of whitening polyacrylate, enhance the wear resistance of the material, and overcome the disadvantage of poor water resistance of strontium aluminate, thereby improving the water resistance of the material, and after organic modification, the dispersion performance of strontium aluminate in the coating system is significantly improved, thereby improving the brightness of the material after stopping excitation, ensuring the warning function of the material at night;

[0142] By comparing the data of Example 12 and Comparative Example 2, it can be found that the wear resistance and brightness of the coating product of the coating composition prepared in Example 12 after stopping excitation for 60 minutes are significantly improved, and the self-repair time is significantly increased, indicating that by modifying the epoxy group on the surface of the self-repairing filler, the epoxy group is cross-linked with the carboxyl group on methyl carbonate-4-cycloocten-1-yl ester, so that the carbonate is uniformly dispersed on the self-repairing surface, and then a stable coating structure is formed by self-polymerization and double bond polymerization on the surface of the self-repairing filler. Compared with direct solution polymerization, the self-polymerization reaction of methyl carbonate-4-cycloocten-1-yl ester is inhibited, thereby significantly improving the dispersion ability of the functionalized filler, and the transparent polycarbonate component is dispersed inside the coating, which greatly improves the absorption capacity of strontium aluminate to ultraviolet rays, thereby enhancing the brightness after stopping excitation for 60 minutes, and promoting the activation of the photoinitiator inside the functionalized filler, promoting the self-polymerization repair process of the coated product, and ensuring the improvement of the fluorescence performance of the coated product;

[0143] By comparing the data of Example 12 and Comparative Example 3, it can be found that the adhesion ability and retroreflection coefficient of the coating composition coated product prepared in Example 12 are significantly reduced, indicating that after the polyacrylate organic chain segment is modified by the epoxy group and the fluorescent whitening group, the epoxy group improves the fluidity and wetting behavior of the coating on the substrate, which helps the coating to form a more uniform and tight covering layer, thereby improving the adhesion, and the three-membered ring structure of the epoxy group is highly reactive in the ring-opening reaction. When the epoxy group contacts the functional group on the surface of the substrate, a chemical reaction can occur through the formation of covalent bonds, thereby greatly improving the adhesion strength of the coating; the electrons of the fluorescent whitening group are excited to a higher energy level, and then when the electrons fall back to a low energy level, they release energy in the form of light with a longer wavelength, and after releasing the blue light, the yellow or dark tone of the material itself is compensated, making the material look whiter and brighter, and in a lower light environment, the material appears brighter, thereby improving its overall visual appeal, ensuring the eye-catching effect of the coating during the day and the warning effect at night;

[0144] The present invention is to perform surface modification on the phosphor to enhance its water resistance and compatibility with organic materials, and after using it as a cross-linking agent to react with whitening polyacrylate, the high reflective properties of the whitening polyacrylate are synergistically coordinated to enhance its warning effect at night, and the transparent material is modified on the surface of the self-repairing material to enhance the ultraviolet light transmission performance inside the material, thereby improving the ultraviolet light absorption performance of the phosphor and ultraviolet initiator, and finally preparing a coating composition.

[0145] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A coating composition for road marking, characterized in that: The raw material composition includes the following parts by weight: 40-60 parts of whitening polyacrylic acid resin, 20-30 parts of functional filler and 6-12 parts of auxiliary materials; The preparation method of the functionalized filler comprises the following steps: A1. Add self-repairing filler, methyl 4-cycloocten-1-yl carbonate, triethylamine and N,N-dimethylformamide into a reactor, raise the temperature of the reactor to 60-80°C, keep the temperature for 40-60 minutes, and post-treat to obtain a functionalized filler precursor; A2. Add the functional filler precursor and N,N-dimethylformamide into the ultrasonic instrument, set the frequency of the ultrasonic instrument to 10-20kHz, increase the temperature to 60-80°C, add azobisisobutyronitrile into the ultrasonic instrument, keep the temperature for 1-2h, and post-treat to obtain the functional filler.

2. A coating composition for road marking according to claim 1, characterized in that: In step A1, the amount ratio of self-healing filler, methyl 4-cycloocten-1-yl carbonate, triethylamine and N,N-dimethylformamide is 8-10g:4-5g:2-3g:60-70mL; in step A2, the amount ratio of functionalized filler precursor, N,N-dimethylformamide and azobisisobutyronitrile is 4-5g:15-20mL:0.1-0.2g.

3. The coating composition for road marking according to claim 1, characterized in that: The preparation method of the self-repairing filler comprises the following steps: B1, adding allyl methyl carbonate, triphenoxy vinyl silane, 4,4'-dimethoxybenzophenone and methyl orthosilicate into a reaction kettle and stirring for 5-10 minutes to obtain an oil phase solution; B2, adding the oil phase solution into an ultrasonic emulsifier, and pouring sorbitan oleate and deionized water into the ultrasonic emulsifier, setting the frequency of the ultrasonic emulsifier to 20-40kHz, and ultrasonicating for 20-30min at room temperature to obtain a mixed emulsion; B3. Add the mixed emulsion into the reactor and stir. Add saturated sodium hydroxide solution to the reactor to adjust the system pH to 8-10. Raise the temperature of the reactor to 40-50°C. After keeping warm for 2-3 hours, lower the temperature of the reactor to 0-5°C. Add the modifier twice in equal amounts. After both additions, keep warm for 1-2 hours. Post-treat to obtain the self-healing filler.

4. The coating composition for road marking according to claim 3, characterized in that: In step B1, the dosage ratio of allyl methyl carbonate, triphenoxy vinyl silane, 4,4'-dimethoxybenzophenone and methyl orthosilicate is 5-8g:3-5g:0.3-0.5g:20-30mL; in step B2, the dosage ratio of oil phase solution, sorbitan oleate and deionized water is 10-12mL:3-4mL:40-60mL; in step B3, the dosage ratio of mixed emulsion and modifier is 40mL:3-5mL, and the modifier is obtained by mixing vinyl trimethoxy silane and 3-(2,3-epoxypropoxy)propyl trimethoxy silane in a volume ratio of 1mL:1-1.5mL.

5. The coating composition for road marking according to claim 1, characterized in that: The preparation method of the whitening polyacrylic acid resin is as follows: acrylic acid, 1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 1-allyloxy-2,3-propylene oxide, azobisisobutyronitrile and dimethyl sulfoxide are added into a reaction kettle and stirred, the temperature of the reaction kettle is increased to 60-80°C, and after being kept warm and stirred for 1-2 hours, an afterglow crosslinking agent and benzoic acid are added into the reaction kettle, and the reaction is kept warm for 20-30 minutes, and the whitening polyacrylic acid resin is obtained by post-treatment.

6. A coating composition for road marking according to claim 5, characterized in that: The stirring rate of the reaction kettle is 80-120rpm, and the dosage ratio of acrylic acid, 1,2-bis(5-methyl-2-benzoxazolyl)-ethylene, 1-allyloxy-2,3-propylene oxide, azobisisobutyronitrile, dimethyl sulfoxide, and afterglow crosslinking agent benzoic acid is 8-10g:2-3g:4-5g:0.3-0.5g:45-60mL:2-3g:0.8-1g.

7. The coating composition for road marking according to claim 5, characterized in that: The preparation method of the afterglow crosslinking agent comprises the following steps: C1. Add 3-(methacryloyloxy)propyltrimethoxysilane and anhydrous ethanol to a reactor, stir at room temperature for 15 minutes, then add strontium aluminate, seal the reactor, heat in a water bath at 50-60° C. for 2-4 hours, and perform post-treatment to obtain modified strontium aluminate; C2. Place the modified strontium aluminate in a reactor filled with (hydroxymethyl) acrylate / ethylene glycol solution, raise the temperature of the reactor to 60-80°C, and dropwise add potassium persulfate while stirring until a flocculent precipitate is produced, and post-treat to obtain an afterglow crosslinking agent.

8. The coating composition for road marking according to claim 7, characterized in that: In step C1, the stirring rate of the reactor is 80-120 rpm, and the dosage ratio of 3-(methacryloyloxy)propyltrimethoxysilane, anhydrous ethanol and strontium aluminate is 4-5 g:40-60 mL:20-30 g; in step C2, the dosage ratio of modified strontium aluminate, (hydroxymethyl) acrylate / ethylene glycol solution and potassium persulfate is 4-5 g:20-25 mL:0.3-0.5 g, and the (hydroxymethyl) acrylate / ethylene glycol solution is obtained by mixing (hydroxymethyl) acrylate and ethylene glycol in a dosage ratio of 1 mL:3-5 mL.

9. The method for preparing a coating composition for road marking according to any one of claims 1 to 8, characterized in that: The following steps are involved: Add whitening polyacrylic acid resin, functional repair filler, titanium dioxide, leveling agent, dispersant and ultraviolet absorber into a reaction kettle, mix evenly, and pass through a 300-500 mesh sieve to obtain a coating composition.

Images