Anti-crack road marking paint suitable for high-cold region and preparation method thereof

Abstract

The present application relates to a kind of anti-crack road marking paint suitable for alpine region and preparation method thereof, belong to the field of coating technology.The present application is by synthesizing allyl silicon modified pyridine quaternary ammonium salt monomer containing silicon atom, pyridine quaternary ammonium salt and branched fatty chain and spiro ring thioether quaternary ammonium salt monomer containing sulfide, carboxyl, quaternary ammonium salt and spiro ring structure, and two monomers and butyl acrylate, decyl acrylate are carried out emulsion polymerization reaction, and polyacrylate emulsion is prepared, then polyacrylate emulsion, rutile titanium dioxide, mica powder, talcum powder and alumina fiber are mixed, and road marking paint is prepared.The road marking paint of the present application has good adhesion, wear resistance, water resistance, alkali resistance, flexibility, glass bead firm adhesion and anti-freezing performance simultaneously.

Description

Technical Field

[0001] This invention relates to a crack-resistant road marking coating suitable for cold regions and its preparation method, belonging to the field of coating technology. Background Technology

[0002] In recent years, many colored pavement markings have appeared on roads across China. These markings not only decorate the road surface but also serve to warn drivers, thus ensuring the safety of vehicles and pedestrians. Road markings are a type of safety marker. Traffic safety management departments use road marking paint to delineate vehicle lanes and channel traffic, thereby strengthening traffic safety management, reducing vehicle and personal accidents, and beautifying urban roads. Road traffic markings are mainly applied to the road surface and are exposed to sun, rain, wind, snow, ice, and the impact and wear of vehicles; therefore, their performance is subject to strict requirements.

[0003] Road marking paints can be categorized into two types based on their application methods: hot-melt and cold-applied. Hot-melt road marking paints are physically drying, with anti-skid aggregates typically pre-mixed in the paint. Application temperatures exceed 200℃, resulting in high energy consumption. Because the film-forming material is thermoplastic resin, it is prone to deformation and cracking at high temperatures, making large-area application difficult and resulting in poor durability. Two-component cold-applied paints are chemically cross-linked and cured, applied at room temperature. During application, the two-component base material is mixed and applied to the road surface, followed immediately by the application of non-colored anti-skid aggregates. A colored topcoat is then applied, leading to high costs and complex application processes. Single-component cold-applied paints are physically drying, with finer anti-skid aggregates typically pre-mixed in the paint. Application at room temperature, however, the presence of volatile organic solvents causes significant environmental pollution. It also exhibits poor adhesion to the substrate, as well as poor wear resistance, durability, and low-temperature crack resistance.

[0004] Therefore, there is an urgent need to develop an environmentally friendly, single-component, cold-applied road marking paint with good adhesion, abrasion resistance, and low-temperature crack resistance. Summary of the Invention

[0005] The purpose of this invention is to provide a crack-resistant road marking coating suitable for cold regions and its preparation method, so as to solve the problems of poor adhesion, abrasion resistance and low-temperature crack resistance of current single-component cold-applied road marking coatings.

[0006] This invention provides a crack-resistant road marking coating suitable for high-altitude and cold regions, composed of acrylic emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber. The acrylic emulsion is prepared by emulsion polymerization of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The structure of the allylsilane-modified pyridine quaternary ammonium salt monomer is as follows:

[0007] ;

[0008] The structure of the spirocyclic sulfide quaternary ammonium salt monomer is as follows:

[0009] .

[0010] Preferably, the mass ratio of the acrylate emulsion, rutile titanium dioxide, mica powder, talc powder and alumina fiber is 30~35:8~11:6~9:20~30:10~15.

[0011] Preferably, the mica powder has an average flake diameter of 5-15 μm, the talc powder has an average particle size of 10-20 μm, and the alumina fiber has an average length of 40-60 μm and an average diameter of 5-9 μm.

[0012] Preferably, the emulsion polymerization reaction is carried out as follows: allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, initiator, emulsifier and water are mixed and reacted at 80~85℃ for 5~7h, cooled to room temperature and the pH of the reaction product is adjusted to 7.5 with ammonia water to obtain acrylate emulsion.

[0013] Preferably, the initiator is sodium persulfate and the emulsifier is dodecylphenol polyoxyethylene ether.

[0014] Preferably, the initiator is 1-2% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate; the emulsifier is 3-4% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate; and the water is 55-60% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate.

[0015] Preferably, the preparation method of the allylsilane-modified pyridine quaternary ammonium salt monomer is as follows: 4-tert-butylaminopyridine and n-butyllithium are reacted and then reacted with allyl dimethylchlorosilane to obtain allyl organosilicon pyridine, wherein the molar ratio of 4-tert-butylaminopyridine, n-butyllithium and allyl dimethylchlorosilane is 1:1:1; then, allyl organosilicon pyridine and (1-bromoethyl)cyclohexane in a molar ratio of 1:1.2~1.3 are subjected to a quaternization reaction, and after purification, allylsilane-modified pyridine quaternary ammonium salt monomer is obtained.

[0016] Preferably, the preparation method of the spirocyclic sulfide quaternary ammonium salt monomer is as follows: spirocyclic ethylenedithiol and dimethylallylamine are subjected to an addition reaction, followed by reaction with maleic anhydride to obtain a maleic acid-grafted spirocyclic sulfide compound, wherein the molar ratio of spirocyclic ethylenedithiol, dimethylallylamine, and maleic anhydride is 1:1:1; then, the maleic acid-grafted spirocyclic sulfide compound with a molar ratio of 1:1.2~1.3 is subjected to a quaternization reaction with tert-butane bromide, and after purification, the spirocyclic sulfide quaternary ammonium salt monomer is obtained.

[0017] Preferably, the preparation method of the spirocycloethylenedithiol is as follows: spirocycloethylene glycol and thionyl chloride in a molar ratio of 1:2.1 are subjected to a chlorination reaction to obtain spirocycloethylene glycol chloride; then sodium dithiocarbonate and spirocycloethylene glycol chloride in a molar ratio of 2.5:1 are mixed and reacted in a solvent at 68~70℃ for 7~9h, and after purification, spirocycloethylenedithiol is obtained.

[0018] The present invention also provides a method for preparing the anti-crack road marking paint suitable for high-altitude and cold regions as described above, comprising the following steps: mixing acrylic emulsion, rutile titanium dioxide, mica powder, talc powder and alumina fiber to obtain the paint.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] (1) This invention synthesizes an allylsilane-modified pyridine quaternary ammonium salt monomer containing silicon atoms, pyridine quaternary ammonium salt, and branched aliphatic chains, as well as a spirocyclic sulfide quaternary ammonium salt monomer containing sulfide, carboxyl groups, quaternary ammonium salt, and spirocyclic structures. The two monomers are then subjected to emulsion polymerization with butyl acrylate and decyl acrylate to prepare a polyacrylate emulsion. The polyacrylate emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber are then mixed to prepare a road marking paint. The abundant quaternary ammonium salt groups and carboxyl groups in the polyacrylate effectively wet and stabilize the dispersion of rutile titanium dioxide, mica powder, talc powder, and alumina fiber, improving the uniformity and stability of the filler dispersion, ensuring the uniform embedding of the filler in the coating film, and fully utilizing the reinforcing properties of the filler. This results in the road marking paint exhibiting good wear resistance, water resistance, and alkali resistance. In addition, the spirocyclic structure and organosilicon in polyacrylate possess both good toughness and strength, which can further improve the mechanical properties of the coating film; butyl acrylate, decyl acrylate, and thioether bonds have good flexibility, which can effectively improve the flexibility and freeze resistance of the coating film; the spirocyclic structure, pyridine quaternary ammonium salt, tert-butyl quaternary ammonium salt, and branched aliphatic chains have significant steric hindrance, which can not only prevent filler agglomeration and improve filler dispersion uniformity, but also improve the bonding strength between fillers or glass beads and polyacrylate, as well as the bonding strength between the coating film and the substrate, through mechanical intercalation and physical cross-linking, thereby improving the coating film's adhesion, abrasion resistance, water resistance, alkali resistance, flexibility, strong adhesion of glass beads, and freeze resistance.

[0021] (2) In the road marking paint of the present invention, mica powder, talc powder and alumina fiber have a synergistic effect. The flake mica powder is elastic, has good bending and flexibility, and has good chemical stability. The talc powder has a certain lubricity, which can increase the tensile strength, shear strength and deformation resistance of the coating film, and can improve the adhesion of the coating. The alumina fiber is fibrous and can play a bridging role. Through electrostatic attraction, conjugation effect and mechanical interlocking with the quaternary ammonium salt group, pyridine group and branched aliphatic chain in polyacrylate, it can improve the interaction force with the coating film. Through cross stacking and physical winding, the flake mica powder and talc powder are firmly fixed in the coating film, which can improve the mechanical properties and durability of the coating film. When the coating film is placed in a low temperature freezing environment, the easily deformable alumina fiber and the elastic flake mica powder can prevent the coating film from cracking at low temperature and improve the freeze resistance. Attached Figure Description

[0022] Figure 1 The 1H NMR spectrum of the allylsilane-modified pyridine quaternary ammonium salt monomer prepared in Example 1 of this invention;

[0023] Figure 2 The image shows the 1H NMR spectrum of the spirocyclic sulfide quaternary ammonium salt monomer prepared in Example 1 of this invention. Detailed Implementation

[0024] The following examples are intended to further illustrate the content of the present invention, rather than to limit the scope of protection of the present invention.

[0025] Specific embodiments of the anti-crack road marking coating suitable for high-altitude and cold regions and its preparation method of the present invention are as follows:

[0026] Example 1

[0027] The preparation method of the anti-cracking road marking paint suitable for cold regions in this embodiment includes the following steps:

[0028] (1) Add 4-tert-butylaminopyridine and toluene in a mass ratio of 3:70 to a reaction vessel, then introduce nitrogen gas into the reaction vessel and cool it to -75°C. Then add a toluene solution of n-butyllithium with a concentration of 2.2 mol / L to the reaction vessel and stir the reaction at room temperature for 2.5 h. After the reaction is completed, cool it to -75°C and add allyl dimethylchlorosilane to the reaction vessel. Then stir the reaction at room temperature for 15 h, filter, and distill the filtrate under reduced pressure to obtain allyl organosilicon pyridine. The molar ratio of 4-tert-butylaminopyridine, n-butyllithium and allyl dimethylchlorosilane is 1:1:1. The chemical structure of 4-tert-butylaminopyridine is as follows: ;

[0029] The chemical structure of allyl organosilicon pyridine is as follows: .

[0030] (2) Allyl organosilicon pyridine, (1-bromoethyl)cyclohexane, and acetone in a molar ratio of 1:1.2:8 were added to a reaction vessel, heated to 80°C, and stirred under reflux for 9 h. Unreacted (1-bromoethyl)cyclohexane and acetone were removed by vacuum distillation to obtain a crude product. The crude product was purified by column chromatography using a mixed solvent of ethyl acetate, dichloromethane, and petroleum ether in a volume ratio of 7:3:1 as the eluent to obtain an allyl silicon-modified pyridine quaternary ammonium salt monomer. The 1H NMR spectrum of the allyl silicon-modified pyridine quaternary ammonium salt monomer is shown below. Figure 1 As shown, the chemical structure is as follows: .

[0031] (3) Spirocycloethylene glycol and pyridine in a mass ratio of 3:5 were added to a reaction vessel, heated to 70°C, and stirred. Sulfoxide (the molar ratio of spirocycloethylene glycol to sulfoxide was 1:2.1) was added dropwise to the reaction vessel. After the addition was complete, the reaction was stirred for 4 hours. The pyridine and unreacted sulfoxide were removed by vacuum distillation to obtain spirocycloethylene glycol chloride. Sodium dithiocarbonate solution and tetrahydrofuran solution of spirocycloethylene glycol chloride were added to the reaction vessel, stirred evenly, heated to 68°C, and stirred for 7 hours. After the reaction was completed, ethyl acetate was added, and the mixture was allowed to stand for separation. The organic phase was then distilled under reduced pressure to obtain spirocycloethylenedithiol. The mass fraction of sodium dithiocarbonate solution was 25%, the mass fraction of tetrahydrofuran solution of spirocycloethylene glycol chloride was 32%, and the molar ratio of sodium dithiocarbonate to spirocycloethylene glycol chloride was 2.5:1. The chemical structure of spirocycloethylenedithiol is as follows: .

[0032] (4) Spirocycloethylenedithiol, dimethylallylamine, triethylamine, and tetrahydrofuran in a molar ratio of 1:1:0.02:6 were added to a reaction vessel and stirred at room temperature for 4 h. Then, maleic anhydride in an equimolar amount with spirocycloethylenedithiol was added to the reaction vessel, heated to 60 °C, stirred and refluxed for 7 h, and then distilled under reduced pressure to remove triethylamine and tetrahydrofuran to obtain maleic acid-grafted spirocyclothiol compound. Then, maleic acid-grafted spirocyclothiol compound, tert-butane bromide, and acetone in a molar ratio of 1:1.2:13 were added to a reaction vessel, heated to 80 °C, stirred and reacted for 12 h, and then distilled under reduced pressure to remove acetone to obtain crude product. The crude product was purified by column chromatography with ethyl acetate and methanol in a volume ratio of 6:1 to obtain spirocyclothioether quaternary ammonium salt monomer. The 1H NMR spectrum of the spirocyclothioether quaternary ammonium salt monomer is shown below. Figure 2 As shown, the chemical structure of the spirocyclic sulfide quaternary ammonium salt monomer is as follows: .

[0033] (5) Allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, sodium persulfate initiator, dodecylphenol polyoxyethylene ether, and deionized water were added to a reaction vessel, stirred evenly, heated to 80°C, stirred for 5 hours, cooled to room temperature, and the pH of the reaction product was adjusted to 7.5 with ammonia water to obtain an acrylate emulsion; wherein the mass ratio of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate was 2:3. The ratio of sodium persulfate to initiator is 7:4, which is 1% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The mass of dodecylphenol polyoxyethylene ether is 3% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The mass of deionized water is 55% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate.

[0034] (6) An acrylic emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber in a mass ratio of 30:8:6:20:10 were added to a mixing tank and stirred until homogeneous to obtain a crack-resistant road marking paint suitable for cold regions. The mica powder had an average flake diameter of 5 μm, the talc powder had an average particle size of 10 μm, and the alumina fiber had an average length of 40 μm and an average diameter of 5 μm.

[0035] Example 2

[0036] The preparation method of the anti-cracking road marking paint suitable for cold regions in this embodiment includes the following steps:

[0037] (1) 4-tert-butylaminopyridine and toluene in a mass ratio of 3:75 were added to a reaction vessel. Nitrogen gas was then introduced into the reaction vessel, and the temperature was lowered to -75°C. A toluene solution of n-butyllithium with a concentration of 2.2 mol / L was then added to the reaction vessel, and the mixture was stirred at room temperature for 2.8 h. After the reaction was completed, the temperature was lowered to -75°C, and allyl dimethylchlorosilane was added to the reaction vessel. The mixture was stirred at room temperature for 17 h, filtered, and the filtrate was distilled under reduced pressure to obtain allyl organosilicon pyridine. The molar ratio of 4-tert-butylaminopyridine, n-butyllithium, and allyl dimethylchlorosilane was 1:1:1. The chemical structure of 4-tert-butylaminopyridine is as follows: ;

[0038] The chemical structure of allyl organosilicon pyridine is as follows: .

[0039] (2) Allyl organosilicon pyridine, (1-bromoethyl)cyclohexane and acetone in a molar ratio of 1:1.2:9 were added to a reaction vessel, heated to 82°C, stirred and refluxed for 11 h, and then distilled under reduced pressure to remove unreacted (1-bromoethyl)cyclohexane and acetone to obtain a crude product. The crude product was purified by column chromatography using a mixed solvent of ethyl acetate, dichloromethane and petroleum ether in a volume ratio of 7:3:1 as the eluent to obtain an allyl silicon-modified pyridine quaternary ammonium salt monomer. The chemical structure of the allyl silicon-modified pyridine quaternary ammonium salt monomer is as follows: .

[0040] (3) Spirocycloethylene glycol and pyridine in a mass ratio of 3:5 were added to a reaction vessel, heated to 72°C, and stirred. Sulfoxide (the molar ratio of spirocycloethylene glycol to sulfoxide was 1:2.1) was added dropwise to the reaction vessel. After the addition was complete, the reaction was stirred for 4.5 h. The pyridine and unreacted sulfoxide were removed by vacuum distillation to obtain spirocycloethylene glycol chloride. Sodium dithiocarbonate solution and tetrahydrofuran solution of spirocycloethylene glycol chloride were added to the reaction vessel, stirred evenly, heated to 69°C, and stirred for 8 h. After the reaction was completed, ethyl acetate was added, and the mixture was allowed to stand for separation. The organic phase was then distilled under reduced pressure to obtain spirocycloethylenedithiol. The mass fraction of sodium dithiocarbonate solution was 26%, the mass fraction of tetrahydrofuran solution of spirocycloethylene glycol chloride was 33%, and the molar ratio of sodium dithiocarbonate to spirocycloethylene glycol chloride was 2.5:1. The chemical structure of spirocycloethylenedithiol is as follows: .

[0041] (4) Spirocycloethylenedithiol, dimethylallylamine, triethylamine and tetrahydrofuran in a molar ratio of 1:1:0.02:7 were added to a reaction vessel and stirred at room temperature for 5 h. Then, maleic anhydride in an equimolar amount with spirocycloethylenedithiol was added to the reaction vessel, heated to 65 °C, stirred and refluxed for 8 h, and then removed by vacuum distillation to remove triethylamine and tetrahydrofuran to obtain maleic acid-grafted spirocyclothiol compound. Then, maleic acid-grafted spirocyclothiol compound, tert-butane bromide and acetone in a molar ratio of 1:1.3:14 were added to a reaction vessel, heated to 82 °C, stirred and reacted for 13 h, and then removed by vacuum distillation to obtain crude product. The crude product was purified by column chromatography with ethyl acetate and methanol in a volume ratio of 6:1 to obtain spirocyclothioether quaternary ammonium salt monomer. The chemical structure of the spirocyclothioether quaternary ammonium salt monomer is as follows: .

[0042] (5) Allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, sodium persulfate initiator, dodecylphenol polyoxyethylene ether, and deionized water were added to a reaction vessel, stirred evenly, heated to 83°C, stirred for 6 hours, cooled to room temperature, and the pH of the reaction product was adjusted to 7.5 with ammonia water to obtain an acrylate emulsion; wherein the mass ratio of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate was 3:4:8. 5. The mass of sodium persulfate initiator is 1.5% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate and decyl acrylate; the mass of dodecylphenol polyoxyethylene ether is 3.5% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate and decyl acrylate; and the mass of deionized water is 58% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate and decyl acrylate.

[0043] (6) An acrylic emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber in a mass ratio of 32:9:7:25:13 were added to a mixing tank and stirred until homogeneous to obtain an anti-crack road marking paint suitable for cold regions. The mica powder had an average flake diameter of 10 μm, the talc powder had an average particle size of 15 μm, and the alumina fiber had an average length of 50 μm and an average diameter of 7 μm.

[0044] Example 3

[0045] The preparation method of the anti-cracking road marking paint suitable for cold regions in this embodiment includes the following steps:

[0046] (1) Add 4-tert-butylaminopyridine and toluene in a mass ratio of 3:80 to a reaction vessel, then introduce nitrogen gas into the reaction vessel and cool it to -75°C. Then add a toluene solution of n-butyllithium with a concentration of 2.2 mol / L to the reaction vessel and stir the reaction at room temperature for 3 h. After the reaction is completed, cool it to -75°C and add allyl dimethylchlorosilane to the reaction vessel. Then stir the reaction at room temperature for 18 h, filter, and distill the filtrate under reduced pressure to obtain allyl organosilicon pyridine. The molar ratio of 4-tert-butylaminopyridine, n-butyllithium and allyl dimethylchlorosilane is 1:1:1. The chemical structure of 4-tert-butylaminopyridine is as follows: ;

[0047] The chemical structure of allyl organosilicon pyridine is as follows: .

[0048] (2) Allyl organosilicon pyridine, (1-bromoethyl)cyclohexane and acetone in a molar ratio of 1:1.3:10 were added to a reaction vessel, heated to 85°C, and stirred under reflux for 12 h. Unreacted (1-bromoethyl)cyclohexane and acetone were removed by vacuum distillation to obtain a crude product. The crude product was purified by column chromatography using a mixed solvent of ethyl acetate, dichloromethane and petroleum ether in a volume ratio of 7:3:1 as the eluent to obtain an allyl silicon-modified pyridine quaternary ammonium salt monomer. The chemical structure of the allyl silicon-modified pyridine quaternary ammonium salt monomer is as follows: .

[0049] (3) Spirocycloethylene glycol and pyridine in a mass ratio of 3:5 were added to a reaction vessel, heated to 75°C, and stirred. Sulfoxide (the molar ratio of spirocycloethylene glycol to sulfoxide was 1:2.1) was added dropwise to the reaction vessel. After the addition was complete, the reaction was stirred for 5 hours. The pyridine and unreacted sulfoxide were removed by vacuum distillation to obtain spirocycloethylene glycol chloride. Sodium dithiocarbonate solution and tetrahydrofuran solution of spirocycloethylene glycol chloride were added to the reaction vessel, stirred evenly, heated to 70°C, and stirred for 9 hours. After the reaction was completed, ethyl acetate was added, and the mixture was allowed to stand for separation. The organic phase was then distilled under reduced pressure to obtain spirocycloethylenedithiol. The mass fraction of sodium dithiocarbonate solution was 28%, the mass fraction of tetrahydrofuran solution of spirocycloethylene glycol chloride was 34%, and the molar ratio of sodium dithiocarbonate to spirocycloethylene glycol chloride was 2.5:1. The chemical structure of spirocycloethylenedithiol is as follows: .

[0050] (4) Spirocycloethylenedithiol, dimethylallylamine, triethylamine and tetrahydrofuran in a molar ratio of 1:1:0.03:8 were added to a reaction vessel and stirred at room temperature for 6 h. Then, maleic anhydride in an equimolar amount with spirocycloethylenedithiol was added to the reaction vessel, heated to 70 °C, stirred and refluxed for 9 h, and then distilled under reduced pressure to remove triethylamine and tetrahydrofuran to obtain maleic acid-grafted spirocyclothiol compound. Then, maleic acid-grafted spirocyclothiol compound, tert-butane bromide and acetone in a molar ratio of 1:1.3:15 were added to a reaction vessel, heated to 85 °C, stirred and reacted for 15 h, and then distilled under reduced pressure to remove acetone to obtain crude product. The crude product was purified by column chromatography with ethyl acetate and methanol in a volume ratio of 6:1 to obtain spirocyclothioether quaternary ammonium salt monomer. The chemical structure of the spirocyclothioether quaternary ammonium salt monomer is as follows: .

[0051] (5) Allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, sodium persulfate initiator, dodecylphenol polyoxyethylene ether, and deionized water were added to a reaction vessel, stirred evenly, heated to 85°C, stirred for 7 hours, cooled to room temperature, and the pH of the reaction product was adjusted to 7.5 with ammonia water to obtain an acrylate emulsion; wherein the mass ratio of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate was 4:5. The ratio is 9:6, the mass of sodium persulfate initiator is 2% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate and decyl acrylate, the mass of dodecylphenol polyoxyethylene ether is 4% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate and decyl acrylate, and the mass of deionized water is 60% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate and decyl acrylate.

[0052] (6) An acrylic emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber in a mass ratio of 35:11:9:30:15 were added to a mixing tank and stirred until homogeneous to obtain a crack-resistant road marking paint suitable for cold regions. The mica powder had an average flake diameter of 15 μm, the talc powder had an average particle size of 20 μm, and the alumina fiber had an average length of 60 μm and an average diameter of 9 μm.

[0053] Comparative Example 1

[0054] The difference between the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-cracking road marking paint suitable for cold regions in Example 1 is only that in step (5) of the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example, the allyl silicon modified pyridine quaternary ammonium salt monomer is replaced with an allyl silicon modified piperidine quaternary ammonium salt monomer. The preparation method of the allyl silicon modified piperidine quaternary ammonium salt monomer is as follows:

[0055] (1) Add 4-amino-1-methylpiperidine and toluene in a mass ratio of 3:70 to a reaction vessel, then introduce nitrogen gas into the reaction vessel and cool it to -75°C. Then add a toluene solution of n-butyllithium with a concentration of 2.2 mol / L to the reaction vessel and stir the reaction at room temperature for 2.5 h. After the reaction is completed, cool it to -75°C and add allyl dimethylchlorosilane to the reaction vessel. Then stir the reaction at room temperature for 15 h, filter, and distill the filtrate under reduced pressure to obtain allyl organosilicon piperidine; the molar ratio of 4-amino-1-methylpiperidine, n-butyllithium and allyl dimethylchlorosilane is 1:1:1.

[0056] (2) Allyl organosilicon piperidine, (1-bromoethyl)cyclohexane and acetone in a molar ratio of 1:1.2:8 were added to a reaction vessel, heated to 80°C, stirred for 9 h, and then distilled under reduced pressure to remove unreacted (1-bromoethyl)cyclohexane and acetone to obtain allyl silicon modified piperidine quaternary ammonium salt monomer.

[0057] Comparative Example 2

[0058] The difference between the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-crack road marking paint suitable for cold regions in Example 1 is that in step (1) of the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example, 4-tert-butylaminopyridine is replaced with N-methylpyridine-4-amine.

[0059] Comparative Example 3

[0060] The difference between the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-crack road marking paint suitable for cold regions in Example 1 is that in step (2) of the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example, (1-bromoethyl)cyclohexane is replaced with tert-bromobutane.

[0061] Comparative Example 4

[0062] The difference between the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-cracking road marking paint suitable for cold regions in Example 1 is only that in step (5) of the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example, the spirocyclic sulfide quaternary ammonium salt monomer is replaced with a spirocyclic ester quaternary ammonium salt monomer. The preparation method of the spirocyclic ester quaternary ammonium salt monomer is as follows:

[0063] (1) Add a 30% (w / w) solution of spirocyclic ethylene glycol in dichloromethane to a reaction vessel, then adjust the temperature to 0°C, start stirring, and add a 25% (w / w) solution of dimethylcarbamoyl chloride in dichloromethane dropwise to the reaction vessel. After the addition is complete, stir and react at room temperature for 6 hours, filter, and distill the filtrate under reduced pressure to obtain an intermediate; add the intermediate, maleic anhydride and tetrahydrofuran (the mass of tetrahydrofuran is 60% of the sum of the masses of the intermediate and maleic anhydride) to a reaction vessel, heat to 60°C, stir and react for 7 hours, distill under reduced pressure to remove tetrahydrofuran, and obtain a maleic acid-grafted spirocyclic thiol compound; the molar ratio of spirocyclic ethylene glycol, dimethylcarbamoyl chloride and maleic anhydride is 1:1:1.

[0064] (2) Maleic acid grafted spirocyclic thiols, tert-butane bromide and acetone in a molar ratio of 1:1.2:13 were added to a reaction vessel, heated to 80°C, stirred for 12 h, and then distilled under reduced pressure to remove acetone and unreacted tert-butane bromide to obtain spirocyclic thioether quaternary ammonium salt monomer.

[0065] Comparative Example 5

[0066] The difference between the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-crack road marking paint suitable for cold regions in Example 1 is that in step (4) of the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example, tert-butane bromide is replaced with (1-bromoethyl)cyclohexane.

[0067] Comparative Example 6

[0068] The difference between the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-cracking road marking paint suitable for cold regions in Example 1 is only that the preparation method of the acrylic emulsion in step (5) of the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example is as follows: Allylsilane-modified pyridine quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, sodium persulfate initiator, dodecylphenol polyoxyethylene ether and deionized water are added to the reaction vessel, stirred evenly, heated to 80°C, stirred and reacted for 5 hours, cooled to room temperature and then treated with ammonia water. The pH of the reaction product was adjusted to 7.5 to obtain an acrylate emulsion. The mass ratio of allylsilane-modified pyridine quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate was 5:7:4. The mass of sodium persulfate initiator was 1% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The mass of dodecylphenol polyoxyethylene ether was 3% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The mass of deionized water was 55% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate.

[0069] Comparative Example 7

[0070] The preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example differs from the preparation method of the anti-cracking road marking paint suitable for cold regions in Example 1 only in that the preparation method of the acrylic emulsion in step (5) of the preparation method of the anti-cracking road marking paint suitable for cold regions in this comparative example is as follows: Spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, sodium persulfate initiator, dodecylphenol polyoxyethylene ether, and deionized water are added to the reaction vessel, stirred evenly, heated to 80°C, stirred and reacted for 5 hours, and then cooled to... After being brought to room temperature, the pH of the reaction product was adjusted to 7.5 with ammonia to obtain an acrylate emulsion. The mass ratio of spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate was 5:7:4. The mass of sodium persulfate initiator was 1% of the sum of the masses of spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The mass of dodecylphenol polyoxyethylene ether was 3% of the sum of the masses of spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The mass of deionized water was 55% of the sum of the masses of spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate.

[0071] Comparative Example 8

[0072] The difference between the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-crack road marking paint suitable for cold regions in Example 1 is that the amount of mica powder used in step (6) of the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example is 0, and the mass ratio of acrylic emulsion, rutile titanium dioxide, talc powder and alumina fiber is 30:8:24:12.

[0073] Comparative Example 9

[0074] The difference between the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-crack road marking paint suitable for cold regions in Example 1 is that the amount of talc powder used in step (6) of the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example is 0, and the mass ratio of acrylic emulsion, rutile titanium dioxide, mica powder and alumina fiber is 30:8:14:22.

[0075] Comparative Example 10

[0076] The difference between the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example and the preparation method of the anti-crack road marking paint suitable for cold regions in Example 1 is that the amount of alumina fiber in step (6) of the preparation method of the anti-crack road marking paint suitable for cold regions in this comparative example is 0, and the mass ratio of acrylic emulsion, rutile titanium dioxide, mica powder and talc powder is 30:8:8:28.

[0077] Experimental Example

[0078] This experimental example is used to evaluate the comprehensive performance of the road marking paints prepared in each embodiment and comparative example, including adhesion, abrasion resistance, water resistance, alkali resistance, flexibility, glass bead adhesion rate, and freeze-thaw resistance. The adhesion test method is as follows: samples were prepared according to the method specified in standard GB / T 1720, and circular scratches were performed on a paint film adhesion tester. The adhesion level was determined according to the rating method. Abrasion resistance was tested according to the method specified in standard GB / T 1768, with a load of 1000g applied to the rubber grinding wheel and 200 rotations. Water resistance was tested according to the method specified in standard GB / T 1733, specifically by applying the road marking paint to a glass slide (100mm × 100mm × 2mm) with a dry film thickness of 50µm, allowing it to stand for 72 hours, and then immersing it in distilled water. The shortest time before cracking, blistering, or wrinkling of the paint film was recorded. Alkali resistance was tested according to the method specified in standard GB / T 1733. Specifically, the road marking paint was applied to a glass slide (100mm×100mm×2mm), with a dry film thickness of 50µm. After 72 hours, the slide was immersed in a saturated calcium hydroxide solution, and the shortest time for cracking, blistering, or wrinkling of the paint film was recorded. Flexibility was tested according to the method specified in standard GB / T 1731, and the experimental results were expressed as the diameter of the smallest shaft that did not cause paint film damage. Glass bead adhesion rate was tested according to the provisions of 6.1.14 "Glass Bead Adhesion Rate" in standard GA-T 298-2001 "Road Marking Paint". The frost resistance test method was as follows: the road marking paint was applied to a cement slab, then allowed to dry at room temperature to obtain the test sample. The test sample was placed in an environment of -50℃, and after 12 hours, the compressive strength was tested using an electronic universal testing machine. Each sample was tested three times, and the average value was calculated after the tests. The adhesion, abrasion resistance, water resistance, alkali resistance, flexibility, glass bead adhesion rate, and freeze-thaw resistance of the road marking coatings prepared in each embodiment and comparative example are shown in Table 1.

[0079] Table 1 shows the adhesion, abrasion resistance, water resistance, alkali resistance, flexibility, glass bead adhesion rate, and freeze-thaw resistance of the road marking coatings prepared in each example and comparative example.

[0080] Road marking paint Adhesion Abrasion resistance (mg) Water resistance (h) Alkali resistance (h) Flexibility (mm) Glass bead adhesion rate (%) Freeze-thaw resistance (MPa) Example 1 1 3.2 ≥110 71 2 98 61.7 Example 2 1 3.5 ≥110 68 3 99 60.9 Example 3 2 3.3 ≥110 69 2 96 62.1 Comparative Example 1 5 28.6 21 11 10 28 11.4 Comparative Example 2 5 25.9 19 9 15 33 9.5 Comparative Example 3 4 27.3 23 14 15 31 10.5 Comparative Example 4 6 29.1 25 12 10 27 10.1 Comparative Example 5 5 25.8 22 13 10 34 11.8 Comparative Example 6 4 26.2 24 16 10 29 12.1 Comparative Example 7 4 24.6 23 15 10 30 10.9 Comparative Example 8 6 26.1 17 12 15 28 9.7 Comparative Example 9 5 24.9 23 9 15 32 10.4 Comparative Example 10 6 27.2 20 10 10 27 11.2

[0081] As shown in Table 1, the road marking coatings prepared in Examples 1-3 of this invention simultaneously possess excellent adhesion, abrasion resistance, water resistance, alkali resistance, flexibility, strong adhesion of glass beads, and antifreeze properties. The road marking coatings prepared by this invention are composed of acrylic emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fibers. The acrylic emulsion is prepared by emulsion polymerization of allylsilane-modified pyridine quaternary ammonium salt monomers containing silicon atoms, pyridine quaternary ammonium salts, and branched aliphatic chains, spirocyclic sulfide quaternary ammonium salt monomers containing sulfides, carboxyl groups, quaternary ammonium salts, and spirocyclic structures, and butyl acrylate and decyl acrylate. The abundant quaternary ammonium salt groups and carboxyl groups in the prepared polyacrylate can effectively wet and stably disperse rutile titanium dioxide, mica powder, talc powder, and alumina fibers, improving the uniformity and stability of filler dispersion, ensuring the uniform embedding of fillers in the coating film, and fully utilizing the reinforcing properties of the fillers, thereby giving the road marking coating excellent abrasion resistance, water resistance, and alkali resistance. In addition, the spirocyclic structure and organosilicon in polyacrylate possess both good toughness and strength, which can further improve the mechanical properties of the coating film; butyl acrylate, decyl acrylate, and thioether bonds have good flexibility, which can effectively improve the flexibility and freeze resistance of the coating film; the spirocyclic structure, pyridine quaternary ammonium salt, tert-butyl quaternary ammonium salt, and branched aliphatic chains have significant steric hindrance, which can not only prevent filler agglomeration and improve filler dispersion uniformity, but also improve the bonding strength between fillers or glass beads and polyacrylate, as well as the bonding strength between the coating film and the substrate, through mechanical intercalation and physical cross-linking, thereby improving the coating film's adhesion, abrasion resistance, water resistance, alkali resistance, flexibility, strong adhesion of glass beads, and freeze resistance.

[0082] As can be seen from Example 1 and Comparative Example 1, after replacing the allylsilane-modified pyridine quaternary ammonium salt monomer with the allylsilane-modified piperidine quaternary ammonium salt monomer, the coating strength is reduced due to the poor rigidity of the piperidine ring. Furthermore, the lack of a conjugated structure results in a lack of conjugation effect between the piperidine and the metal elements in the filler, leading to a decrease in the affinity and bonding strength between the polyacrylate and the filler, and consequently, a reduction in the density and firmness of the coating.

[0083] As can be seen from Example 1 and Comparative Example 4, after replacing the spirocyclic sulfide quaternary ammonium salt monomer with the spirocyclic ester quaternary ammonium salt monomer, the polyacrylate lacks flexible weak polar ether bonds and has more ester groups with strong polarity and poor alkali resistance, resulting in a decrease in the affinity between the polyacrylate and the inorganic filler and inorganic substrate, as well as a decrease in the flexibility and antifreeze properties of the coating film.

[0084] As shown in Examples 1 and Comparative Examples 2-3 and 5, replacing the tert-butyl group linked to the silicon-nitrogen bond with a methyl group, or replacing the cyclohexyl group in the allylsilane-modified pyridine quaternary ammonium salt monomer with a tert-butyl group, or replacing the tert-butyl group in the spirocyclic sulfide quaternary ammonium salt monomer with a cyclohexyl group, all result in a decrease in the overall performance of the coating film. This is because the spirocyclic sulfide quaternary ammonium salt monomer itself contains a spirocyclic structure. When a cyclohexyl group is introduced, the spirocyclic sulfide quaternary ammonium salt monomer becomes too rigid and too flexible, leading to a decrease in the overall flexibility and antifreeze properties of the coating film. On the other hand, the allylsilane-modified pyridine quaternary ammonium salt monomer has a shorter molecular chain. When a cyclohexyl group is introduced, the cyclohexyl group can form a complex with the tert-butyl group linked to the silicon-nitrogen bond, improving the mechanical intercalation and thus enhancing the bonding strength between the polyacrylate and the filler, as well as the overall performance of the coating film.

[0085] As can be seen from Example 1 and Comparative Examples 6-7, when allyl silicon-modified pyridine quaternary ammonium salt monomer and spirocyclic sulfide quaternary ammonium salt monomer are used simultaneously, the two can work together to improve the overall performance of the coating film through group surface activity, steric hindrance effect and mechanical intercalation.

[0086] As shown in Example 1 and Comparative Examples 8-10, in the road marking paint of the present invention, mica powder, talc powder, and alumina fibers have a synergistic effect. The flaky mica powder is elastic, possessing good bending and flexibility, and exhibiting good chemical stability. Talc powder has a certain degree of lubricity, which can increase the tensile strength, shear strength, and resistance to deformation of the coating film, and improve the adhesion of the coating. The alumina fibers, being fibrous, can act as a bridging agent, increasing the interaction force with the coating film through electrostatic attraction, conjugation effect, and mechanical interlocking with the quaternary ammonium salt groups, pyridine groups, and branched aliphatic chains in the polyacrylate. Furthermore, through cross-stacking and physical entanglement, the flaky mica powder and talc powder are firmly fixed in the coating film, improving the mechanical properties and durability of the coating film. When the coating film is placed in a low-temperature freezing environment, the easily deformable alumina fibers and the elastic flaky mica powder can prevent the coating film from cracking at low temperatures and improve its freeze-thaw resistance.

Claims

1. A crack-resistant road marking coating suitable for cold regions, characterized in that, It is composed of acrylate emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber. The acrylate emulsion is prepared by emulsion polymerization of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate. The structure of the allylsilane-modified pyridine quaternary ammonium salt monomer is as follows: ； The structure of the spirocyclic sulfide quaternary ammonium salt monomer is as follows: 。 2. The anti-crack road marking coating suitable for cold regions as described in claim 1, characterized in that, The mass ratio of the acrylate emulsion, rutile titanium dioxide, mica powder, talc powder and alumina fiber is 30~35:8~11:6~9:20~30:10~15.

3. The anti-crack road marking coating suitable for cold regions as described in claim 1, characterized in that, The mica powder has an average flake size of 5-15 μm, the talc powder has an average particle size of 10-20 μm, and the alumina fiber has an average length of 40-60 μm and an average diameter of 5-9 μm.

4. The anti-crack road marking coating suitable for cold regions as described in claim 1, characterized in that, The emulsion polymerization method is as follows: allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, decyl acrylate, initiator, emulsifier and water are mixed and reacted at 80~85℃ for 5~7h. After cooling to room temperature, the pH of the reaction product is adjusted to 7.5 with ammonia water to obtain acrylate emulsion.

5. The anti-crack road marking coating suitable for cold regions as described in claim 4, characterized in that, The initiator is sodium persulfate, and the emulsifier is dodecylphenol polyoxyethylene ether.

6. The anti-crack road marking coating suitable for cold regions as described in claim 4, characterized in that, The initiator is 1-2% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate; the emulsifier is 3-4% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate; and the water is 55-60% of the sum of the masses of allylsilane-modified pyridine quaternary ammonium salt monomer, spirocyclic sulfide quaternary ammonium salt monomer, butyl acrylate, and decyl acrylate.

7. The anti-crack road marking paint suitable for high-altitude and cold regions as described in any one of claims 1-6, characterized in that, The preparation method of the allylsilane-modified pyridine quaternary ammonium salt monomer is as follows: 4-tert-butylaminopyridine and n-butyllithium are reacted and then reacted with allyl dimethylchlorosilane to obtain allyl organosilicon pyridine. The molar ratio of 4-tert-butylaminopyridine, n-butyllithium and allyl dimethylchlorosilane is 1:1:

1. Then, allyl organosilicon pyridine and (1-bromoethyl)cyclohexane with a molar ratio of 1:1.2~1.3 are subjected to quaternization reaction. After purification, the allylsilane-modified pyridine quaternary ammonium salt monomer is obtained.

8. The anti-crack road marking paint suitable for high-altitude and cold regions as described in any one of claims 1-6, characterized in that, The preparation method of the spirocyclic sulfide quaternary ammonium salt monomer is as follows: spirocyclic ethylenedithiol and dimethylallylamine are subjected to an addition reaction, followed by reaction with maleic anhydride to obtain a maleic acid-grafted spirocyclic sulfide compound, wherein the molar ratio of spirocyclic ethylenedithiol, dimethylallylamine, and maleic anhydride is 1:1:1; then, the maleic acid-grafted spirocyclic sulfide compound with a molar ratio of 1:1.2~1.3 is subjected to a quaternization reaction with tert-butane bromide, and after purification, the spirocyclic sulfide quaternary ammonium salt monomer is obtained.

9. The anti-crack road marking coating suitable for cold regions as described in claim 8, characterized in that, The preparation method of the spirocyclic ethylenedithiol is as follows: spirocyclic ethylene glycol and thionyl chloride in a molar ratio of 1:2.1 are subjected to chlorination to obtain spirocyclic ethylene glycol chloride; then sodium dithiocarbonate and spirocyclic ethylene glycol chloride in a molar ratio of 2.5:1 are mixed and reacted in a solvent at 68~70℃ for 7~9h, and after purification, spirocyclic ethylenedithiol is obtained.

10. A method for preparing a crack-resistant road marking paint suitable for high-altitude and cold regions as described in any one of claims 1-9, characterized in that, The process includes the following steps: mixing acrylic emulsion, rutile titanium dioxide, mica powder, talc powder, and alumina fiber to obtain the final product.

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