Two-component flexible road marking paint and preparation method thereof

Abstract

The invention belongs to the technical field of coatings, and particularly relates to a two-component flexible road marking coating and a preparation method thereof. The two-component flexible road marking coating comprises a component A and a component B in a mass ratio of (2.5-3): 1, wherein the component A comprises 5-10 parts of bisphenol epoxy resin with the epoxy value of 0.4-0.55, 40-50 parts of polymer dihydric alcohol, 0.1-0.3 part of a catalyst, 10-15 parts of pigment, 15-20 parts of filler, 5-10 parts of an anti-skid material, 25-35 parts of internally mixed glass beads, 0.5-1 part of a dispersing agent, 0.5-1 part of a defoaming agent, 3-5 parts of a plasticizer and 30-60 parts of a solvent; the component B is a curing agent composed of modified isocyanate and an isocyanate tripolymer according to the mass ratio of (5-8): 1; the modified isocyanate is a compound which is prepared by carrying out hydrosilylation reaction on unsaturated isocyanate and siloxane with a silicon atom number of 2-4 and a hydrogen-containing terminal, and two ends of the modified isocyanate are isocyanato; the coating has excellent brittle fracture resistance, water resistance and wear resistance at low temperature.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to a two-component flexible road marking coating and its preparation method. Background Technology

[0002] Road markings are primarily applied to road surfaces to regulate the passage of vehicles and pedestrians, playing a crucial role in ensuring traffic safety and smooth flow. In recent years, with the continuous expansion of my country's expressway construction and the increasing volume of highway traffic, the demand for road marking paint has shown a rapid upward trend. However, in practical applications, road markings face severe service life challenges, especially in cold regions such as Northeast and Northwest China. Extreme low temperatures can easily cause stress concentration due to thermal expansion and contraction of the paint, leading to cracking of the markings. Simultaneously, the frequent operation of large snowplows during winter snow removal and ice clearing processes causes severe mechanical impact and wear on road markings, further exacerbating detachment and damage, significantly shortening their effective service life and making it difficult to meet the ever-increasing demands for traffic safety.

[0003] Road marking paints come in a wide variety of types. Based on the film-forming material, they are mainly classified into epoxy, polyurethane, polyurea, and acrylic types. Based on chemical composition and curing mechanism, they are classified into single-component and two-component types. Among them, polyurethane two-component road marking paints refer to paints where, during application, component A (usually a prepolymer) containing isocyanate groups is mixed with component B (such as polyols or amine chain extenders) containing hydroxyl or amine groups in a specific ratio. Upon contact, the two components rapidly undergo a cross-linking reaction, forming a dense coating on the road surface. This type of paint has advantages such as good toughness and adjustable curing speed, making it more widely used than other types of road marking paints. For example, patent CN119119852B discloses a two-component polyurethane road marking paint, its preparation method, and its application. The marking paint includes component A and component B. Component A includes vegetable oil polyol, internally mixed glass beads, fillers, and a catalyst; component B includes isocyanate with an NCO functionality equal to or greater than 2. CN108084867B discloses a two-component road marking paint and its preparation method. In the paint, component A uses hydroxyethyl acrylic acid grafted modified hydrogenated bisphenol A epoxy resin, introducing hydrophilic groups such as hydroxyl, carboxyl, and ether bonds to enhance the adhesion between the marking and the wet road surface. At the same time, the polyether polyol and polyisocyanate in component A react with the polyester polyol in component B to generate a closed-cell semi-crosslinked polyurethane elastomer material. Chlorinated hydrocarbons are introduced into component B, so that the hydroxyethyl acrylic acid grafted modified hydrogenated bisphenol A epoxy resin and acrylic resin are introduced during the crosslinking reaction of polyether polyol, polyisocyanate and polyester polyol. The molecules of each film-forming material crosslink with each other, producing a synergistic effect.

[0004] The above are common two-component polyurethane road marking paints. After curing, these road markings exhibit good flexibility, impact resistance, and a long service life. However, their low-temperature toughness is poor, and their durability is insufficient for high-altitude and cold-weather regions. High-altitude and cold-weather temperatures are typically below -10℃ or even lower. In such environments, conventional polyurethane road marking paints partially lose their flexibility, experience reduced adhesion, and become brittle and cracked. Repeated scraping by snowplow blades can easily cause localized peeling or complete detachment of the coating, making it difficult to meet the durability requirements of high-altitude and cold-weather regions.

[0005] Therefore, it is necessary to further improve existing polyurethane two-component road marking paints in order to develop a two-component flexible road marking paint suitable for cold regions. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a two-component flexible road marking paint and its preparation method. The curing agent raw material used in the marking paint, modified isocyanate, is prepared by reacting unsaturated isocyanate with end-hydrogen siloxanes containing 2-5 silicon atoms via a hydrogen silane reaction. The introduced flexible siloxane segments not only improve the toughness of the polyurethane molecular chain segments but also reduce the crystallinity of the urethane crystallization region, thereby improving the material's resistance to brittleness at low temperatures.

[0007] To achieve the above objectives, the following technical solution is adopted:

[0008] A two-component flexible road marking paint includes components A and B in a mass ratio of 2.5-3:1. Component A includes the following raw materials in parts by mass: 5-10 parts of bisphenol-type epoxy resin with an epoxy value of 0.4-0.55, 40-50 parts of polymeric diol, 0.1-0.3 parts of catalyst, 10-15 parts of pigment, 15-20 parts of filler, 5-10 parts of anti-slip agent, 25-35 parts of internally mixed glass beads, 0.5-1 part of dispersant, 0.5-1 part of defoamer, 3-5 parts of plasticizer, and 30-60 parts of solvent.

[0009] Component B comprises the following raw materials in parts by weight: a curing agent composed of modified isocyanate and isocyanate trimer in a mass ratio of 5-8:1; the modified isocyanate is a compound with isocyanate groups at both ends, obtained by hydrosilylation reaction of unsaturated isocyanate with 2-4 terminal hydrogen-containing siloxanes.

[0010] Modified isocyanates contain flexible siloxane segments, which form a "dynamic barrier" to isocyanate groups, resulting in lower reactivity. By compounding modified isocyanates with highly reactive isocyanate trimers in a certain mass, precise control of curing, crosslinking rates, and non-stick drying time can be achieved.

[0011] Furthermore, hydrogen-terminated siloxanes with 2-4 silicon atoms and unsaturated isocyanates are fed in a Si-H, C=C molar ratio of 1:1.04-1.08.

[0012] The unsaturated isocyanate is selected from one or more combinations of 4-(maleimino)phenyl isocyanate, allyl isocyanate, vinyl isocyanate, ethyl isocyanate methacrylate, and ethyl isocyanate acrylate, preferably 4-(maleimino)phenyl isocyanate.

[0013] The hydrogen-terminated siloxane with 2-4 silicon atoms is selected from one or more combinations of 1,1,3,3-tetramethyldisiloxane, 1,1,3,3,5,5-hexamethyltrisiloxane, and octamethyltetrasiloxane. Using hydrogen-terminated siloxanes with 2-5 silicon atoms provides sufficient flexibility while avoiding phase separation and reduced wear resistance of the marking paint due to excessively long chain segments.

[0014] The modified isocyanate is prepared by a method comprising the following steps:

[0015] Under an inert atmosphere, hydrogen-containing siloxanes with 2-4 silicon atoms and organic solvents are added to a reactor. Unsaturated isocyanate and platinum catalyst are added and mixed under controlled temperature for the first time. The reaction is then carried out under controlled temperature again to obtain modified isocyanate.

[0016] The inert atmosphere is established by continuously circulating inert gas after evacuating and filling with dry inert gas 1-5 times. The organic solvent is selected from one or a combination of two or more of toluene, benzene, xylene, and cyclohexane.

[0017] The platinum catalyst is selected from one or a combination of two of chloroplatinic acid and platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane. The amount of platinum catalyst used is 0.01-0.03 wt% of the sum of the mass of the terminal hydrogen-containing siloxane (with 2-4 silicon atoms) and the unsaturated isocyanate. The initial temperature control is maintained at 40-60°C to ensure complete dissolution of the unsaturated isocyanate in the organic solvent. The subsequent temperature control reaction is carried out at 80-90°C for 5-8 hours. Following the subsequent temperature control reaction, a step of distilling off the organic solvent is performed at 40-60°C under a vacuum of 0.01-0.1 MPa.

[0018] The isocyanate trimer is selected from one or a combination of two or more of HDI trimer, IPDI trimer, and TDI trimer.

[0019] The polymer diol has a number-average molecular weight of 1000-2000 and is selected from one or a combination of two of polyether diols and polyester diols.

[0020] Modified isocyanates contain flexible and non-polar siloxane segments, which reduce the interaction force between them and the polar segments of the surrounding urethane esters. This decreases the regularity of the molecular chains and reduces the crystallinity of the urethane crystalline region, thereby improving the material's resistance to brittle fracture at low temperatures.

[0021] The bisphenol type epoxy resin is selected from one or a combination of two or more of bisphenol A type epoxy resin, bisphenol S type epoxy resin, and bisphenol F type epoxy resin.

[0022] The catalyst is selected from one or a combination of two of organotin catalysts and organoamine catalysts.

[0023] The organotin catalyst is selected from one or a combination of two or more of stannous octoate, stannous oleate, and dibutyltin dilaurate.

[0024] The organic amine catalyst is selected from one or a combination of two or more of triethylamine, dimethylbenzylamine, and triethylenediamine.

[0025] The pigment has an average particle size of 0.2-1 μm and is selected from one or a combination of two or more of lead chromium yellow, zinc chromium yellow, and titanium dioxide.

[0026] The filler has an average particle size of 0.5-5 μm and is selected from one or a combination of two or more of heavy calcium carbonate, barium sulfate, talc, and silica powder.

[0027] The anti-slip material has an average particle size of 800-1300 mesh and is selected from one or a combination of two or more of quartz sand, white corundum, and glass sand.

[0028] The internally mixed glass beads have an average particle size of 0.1-1 mm, a sphericity of >80%, and a refractive index of 1.7-2.1.

[0029] The dispersant is selected from one or a combination of two or more of BYK161, BYK110, and BYK180.

[0030] The defoamer is an organosilicon defoamer, selected from one or a combination of two or more of BYK066N, BYK019, BYK020, BYK022, and TEGO Foamex810.

[0031] The plasticizer is selected from one or a combination of two or more of dioctyl phthalate, dibutyl phthalate, diisononyl phthalate, and diisodecyl phthalate.

[0032] Component A may also include 0.3-5 parts by weight of additives.

[0033] There are no particular limitations on the additives mentioned above; any commonly used additives in the field are acceptable, including but not limited to one or a combination of two or more of UV stabilizers, leveling agents, and thixotropic agents.

[0034] The UV absorber is selected from one or a combination of two or more of benzotriazole UV absorbers, salicylate UV absorbers, and benzophenone UV absorbers.

[0035] The leveling agent is one or a combination of two or more selected from TEGO Glide450, TEGO Foamex 825, BYK306, BYK300, Deqian 431, and Deqian 495.

[0036] The thixotropic agent is selected from one or a combination of two or more of the following: fumed silica, BYK 410, BYK 411, polyamide wax, hydrogenated castor oil, and organobentonite.

[0037] The solvent is selected from one or a combination of two or more of xylene, ethyl acetate, butyl acetate, ethylene glycol butyl ether, and propylene glycol methyl ether acetate.

[0038] This invention also provides a method for preparing the above-mentioned two-component flexible road marking paint, comprising the following steps:

[0039] Component A: Mix epoxy resin, polymeric diol, plasticizer, and solvent under controlled temperature. Add catalyst, pigment, filler, internal glass beads, dispersant, defoamer, and optional additives. Mix well, degas, and package.

[0040] Component B: Mix the modified isocyanate and isocyanate trimer thoroughly and then package.

[0041] In component A, the temperature-controlled mixing is carried out at 40-60℃ and a rotation speed of 500-800 r / min. The degassing is performed under vacuum of 0.08-0.09 MPa for 10-30 min.

[0042] The application of a two-component flexible road marking paint includes the following steps: mixing components A and B, applying the mixture to the road surface to be constructed by scraping or spraying to form a coating, sprinkling glass beads on the surface of the coating, and curing to form road markings.

[0043] The coating thickness is 1-2 mm. The average particle size of the surface-sprinkled glass beads is 0.8-1.5 mm, with a sphericity ≥85% and a refractive index of 1.9-2.1. The application rate of the surface-sprinkled glass beads is 300-600 g / m². 2 The glass beads are applied within 0-60 minutes after the coating is formed. The curing conditions are 25-60℃ / 1-5 days.

[0044] Compared with the prior art, the beneficial effects of the present invention are:

[0045] I. The modified isocyanate used as the curing agent raw material in the road marking paint of this invention is prepared by unsaturated isocyanate and hydrogen-terminated siloxanes with 2-4 silicon atoms through a silane-hydrogen reaction. The introduced flexible siloxane segments can not only improve the toughness of polyurethane molecular segments, but also reduce the crystallinity of the urea carbamate crystallization region and improve the material's resistance to brittleness at low temperatures.

[0046] Second, the road marking paint of this invention has excellent water resistance and abrasion resistance. Detailed Implementation

[0047] The present invention will be further described below with reference to specific embodiments, but is not limited to the contents of the specification. Unless otherwise specified, all "parts" mentioned in the embodiments of the present invention are parts by weight. All reagents used are commercially available in the art.

[0048] The internally mixed glass beads have an average particle size of 0.5mm, a sphericity of 85%, and a refractive index of 1.9. They are sourced from Langfang Aolan Glass Microbeads Co., Ltd.

[0049] The average particle size of the surface-sprinkled glass beads is 1.4 mm, the sphericity is 89%, and the refractive index is 1.9. They are from Langfang Aolan Glass Microbeads Co., Ltd.

[0050] Example 1

[0051] 1) Vacuum-filling with dry inert gas and continuous nitrogen flow were performed 3 times. 1 mole of octamethyltetrasiloxane and 4 moles of xylene were added to the reactor. The temperature was controlled at 40℃ for the first time. 2.08 moles of 4-(maleimide)phenyl isocyanate and 0.03 wt% of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, which accounted for the sum of the masses of octamethyltetrasiloxane and 4-(maleimide)phenyl isocyanate, were added. The mixture was then stirred at 300 r / min for 10 min until completely dissolved and mixed. The temperature was controlled at 80℃ for 5 h. After the reaction was completed, xylene was distilled off at 60℃ and a vacuum of 0.01 MPa to obtain the modified isocyanate.

[0052] 2) Component A: Mix 5 parts by weight of epoxy resin Huntsman EPON828, 50 parts by weight of polycarbonate diol Desmophen C2200, 5 parts by weight of plasticizer BASF Palatinol DIDP, 40 parts by weight of xylene, and propylene glycol methyl ether acetate in a volume ratio of 8:2. Heat the mixture to 40°C and stir at 500 rpm for 15 minutes until homogeneous. Add 0.3 parts by weight of dibutyltin dilaurate, 15 parts by weight of rutile titanium dioxide Chemours Ti-Pure R-706, 20 parts by weight of heavy calcium carbonate Omya Carbital 110, 10 parts by weight of quartz sand with an average particle size of 800 mesh, 30 parts by weight of internally mixed glass beads, 1 part by weight of dispersant BYK110, 0.5 parts by weight of defoamer TEGO Foamex 810, and 1 part by weight of UV stabilizer BASF Tinuvin. Mix 1130, 0.3 parts by weight of leveling agent TEGO Glide450, and 2 parts by weight of thixotropic agent BYK 410. Degas under vacuum of 0.08 MPa for 15 minutes, then package.

[0053] Component B: Mix the modified isocyanate and TDI trimer Covestro Desmodur L75 at a mass ratio of 8:1 and package.

[0054] 3) Mix components A and B at a mass ratio of 3:1, apply the mixture to the road surface to be constructed, forming a 2mm thick coating. After 15 minutes, sprinkle glass beads onto the coating surface at a rate of 600g / m². 2 The road markings are completely cured by placing them at 30℃ for 3 days.

[0055] Example 2

[0056] The rest is the same as in Example 1, except that in step 1), 4-(maleimide)phenyl isocyanate is replaced with an equimolar amount of allyl isocyanate.

[0057] Example 3

[0058] The rest is the same as in Example 1, except that in step 1), octamethyltetrasiloxane is replaced with an equimolar amount of 1,1,3,3-tetramethyldisiloxane.

[0059] Example 4

[0060] The rest is the same as in Example 1, except that in step 2), the modified isocyanate and TDI trimer Covestro Desmodur L75 are mixed at a mass ratio of 5:1.

[0061] Example 5

[0062] The rest is the same as in Example 1, except that in step 3), components A and B are mixed at a mass ratio of 2.5:1.

[0063] Example 6

[0064] The rest is the same as in Example 1, except that in step 2), the amount of epoxy resin used is 10 parts by weight.

[0065] Example 7

[0066] 1) Vacuum-filling with dry inert gas and continuous nitrogen flow were performed 3 times. 1 mole of octamethyltetrasiloxane and 4 moles of xylene were added to the reactor. 2.16 moles of 4-(maleimide)phenyl isocyanate were added at 40°C. 0.02 wt% of platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, the sum of the masses of octamethyltetrasiloxane and 4-(maleimide)phenyl isocyanate, were then stirred at 300 r / min for 10 min until completely dissolved and mixed. The reaction was carried out at 80°C for 5 h. After the reaction was completed, xylene was distilled off at 60°C and a vacuum of 0.01 MPa to obtain the modified isocyanate.

[0067] 2) Component A: Mix 10 parts by weight of epoxy resin Huntsman EPON828, 40 parts by weight of polycarbonate diol Desmophen C2200, 5 parts by weight of plasticizer BASF Palatinol DIDP, 40 parts by weight of xylene, and propylene glycol methyl ether acetate in a volume ratio of 8:2. Heat the mixture to 40°C and stir at 500 rpm for 15 minutes until homogeneous. Add 0.3 parts by weight of dibutyltin dilaurate, 15 parts by weight of rutile titanium dioxide Chemours Ti-Pure R-706, 20 parts by weight of heavy calcium carbonate Omya Carbital 110, 10 parts by weight of quartz sand with an average particle size of 800 mesh, 30 parts by weight of internally mixed glass beads, 1 part by weight of dispersant BYK110, 0.5 parts by weight of defoamer TEGO Foamex 810, and 1 part by weight of UV stabilizer BASF Tinuvin. Mix 1130, 0.3 parts by weight of leveling agent TEGO Glide450, and 2 parts by weight of thixotropic agent BYK 410, degas under vacuum of 0.08 MPa for 15 minutes, and then package.

[0068] Component B: Mix the modified isocyanate and TDI trimer Covestro Desmodur L75 at a mass ratio of 5:1 and package.

[0069] 3) Mix components A and B at a mass ratio of 2.5:1, apply the mixture to the road surface to be constructed, forming a 2mm thick coating. After 15 minutes, sprinkle glass beads onto the coating surface at a rate of 600g / m².2 The road markings are completely cured after being placed at 30℃ for 3 days.

[0070] Comparative Example 1

[0071] The rest is the same as in Example 1, except that in step 1), octamethyltetrasiloxane is replaced with an equimolar amount of decamethyldihydropentasiloxane.

[0072] Comparative Example 2

[0073] The rest is the same as in Example 1, except that in step 2), the epoxy resin Huntsman EPON828 is replaced with an equal mass of 1,4-butanediol diglycidyl ether.

[0074] Comparative Example 3

[0075] The rest is the same as in Example 1, except that in step 2), the curing agent is all TDI trimer CovestroDesmodur L75.

[0076] Comparative Example 4

[0077] The rest is the same as in Example 1, except that in step 2), the curing agent is entirely modified isocyanate.

[0078] The calibration lines prepared in the above embodiments and comparative examples were subjected to the following performance tests:

[0079] Low-temperature crack resistance of coating: -30℃ for 4 hours and room temperature for 4 hours constitute one cycle. Record the number of cycles when cracks appear in continuous cycles.

[0080] Water resistance: Tested according to standard JT / T 280-2022 Road marking paint. After soaking in water for 24 hours, there should be no color change, wrinkling, bubbling, or cracking. If any of these phenomena are observed, it is considered unqualified.

[0081] Abrasion resistance: Tested according to standard JT / T 280-2022 road marking paint, ≤40mg is qualified.

[0082] Non-stick drying time: Tested according to standard JT / T 280-2022 road marking paint, ≤60min is qualified.

[0083] Table 1 Performance Test Results

[0084] project Loop count Water resistance abrasion resistance mg Non-stick drying time Example 1 12 qualified 14 55 Example 2 11 qualified 28 52 Example 3 8 qualified 12 44 Example 4 10 qualified 11 42 Example 5 8 qualified 11 59 Example 6 10 qualified 10 58 Example 7 8 qualified 8 53 Comparative Example 1 13 Unqualified 36 66 Comparative Example 2 11 Unqualified 39 54 Comparative Example 3 4 qualified 9 20 Comparative Example 4 15 Unqualified 52 81

[0085] The results of the low-temperature crack resistance test in Table 1 show that the modified isocyanate prepared by hydrosilylation of unsaturated isocyanate with hydrogen-containing siloxanes with 2-4 silicon atoms has a significant effect on improving the low-temperature crack resistance of road marking paint.

[0086] As can be seen from the test results in Table 1, the road marking paint prepared by this invention has excellent water resistance and abrasion resistance. Meanwhile, the inventors discovered that the modified isocyanate prepared by hydrosilylation of 4-(maleimide)phenyl isocyanate with 2-4 terminal hydrogen-containing siloxanes has improved the low-temperature toughness of polyurethane road marking paint and also has a synergistic effect with epoxy resin to improve abrasion resistance. It is speculated that the isocyanate at one end of the maleimide structure can react with the hydroxyl groups on the epoxy resin to form a rigid cross-linked dispersion support, offsetting the negative impact of the flexible chain on the material's hardness and maintaining the paint's abrasion resistance. In contrast, the modified isocyanate prepared by hydrosilylation of allyl isocyanate with 2-4 terminal hydrogen-containing siloxanes has insufficient rigid support due to structural differences, making it difficult to offset the negative impact of the flexible chain on abrasion resistance.

[0087] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. A two-component flexible pavement marking coating, characterized in that, The A component includes 5-10 parts by mass of a bisphenol type epoxy resin with an epoxy value of 0.4-0.55, 40-50 parts by mass of a polymeric diol, 0.1-0.3 parts by mass of a catalyst, 10-15 parts by mass of a pigment, 15-20 parts by mass of a filler, 5-10 parts by mass of an anti-skid material, 25-35 parts by mass of internally mixed glass beads, 0.5-1 parts by mass of a dispersing agent, 0.5-1 parts by mass of an antifoaming agent, 3-5 parts by mass of a plasticizer, and 30-60 parts by mass of a solvent. The B component includes 5-8 parts by mass of a curing agent composed of a modified isocyanate and an isocyanate trimer in a mass ratio of 5-8:1; the modified isocyanate is a compound with two isocyanate groups at the ends, which is prepared by a silicon-hydrogen addition reaction between an unsaturated isocyanate and a terminal hydrogen-containing siloxane with 2-4 silicon atoms.

2. The two-component flexible pavement marking paint according to claim 1, characterized in that, The terminal hydrogen-containing siloxane and the unsaturated isocyanate are fed in a molar ratio of Si-H:C=C of 1:1.04-1.

08.

3. The two-component flexible pavement marking paint according to claim 1, wherein The unsaturated isocyanate is selected from one or a combination of two or more of 4-(maleimide) phenyl isocyanate, allyl isocyanate, vinyl isocyanate, isocyanatoethyl methacrylate, and isocyanate acrylate ethyl ester, and is preferably 4-(maleimide) phenyl isocyanate; the terminal hydrogen-containing siloxane with 2-4 silicon atoms is selected from one or a combination of two or more of 1,1,3,3-tetramethyl disiloxane, 1,1,3,3,5,5-hexamethyl trisiloxane, and octamethyl tetrasiloxane.

4. The two-component flexible pavement marking paint according to claim 1, wherein The modified isocyanate is prepared by a method including the following steps: Under an inert atmosphere, a terminal hydrogen-containing siloxane with 2-4 silicon atoms and an organic solvent are added to a reaction kettle, an unsaturated isocyanate and a platinum catalyst are added for the first time under temperature control, mixed uniformly, and then reacted for the second time under temperature control to obtain the modified isocyanate.

5. The two-component flexible pavement marking paint according to claim 4, wherein The platinum catalyst is selected from one or a combination of two of chloroplatinic acid and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane; the amount of the platinum catalyst is 0.01-0.03 wt% of the total mass of the terminal hydrogen-containing siloxane with 2-4 silicon atoms and the unsaturated isocyanate.

6. The two-component flexible pavement marking paint according to claim 1, wherein The isocyanate trimer is selected from one or a combination of two or more of HDI trimer, IPDI trimer, and TDI trimer.

7. The two-component flexible pavement marking paint according to claim 1, wherein The bisphenol type epoxy resin is selected from one or a combination of two or more of bisphenol A type epoxy resin, bisphenol S type epoxy resin, and bisphenol F type epoxy resin.

8. The two-component flexible pavement marking paint according to claim 1, wherein The polymeric diol has a number average molecular weight of 1000-2000 and is selected from one or a combination of two of polyether diol and polyester diol; the catalyst is selected from one or a combination of two of an organic tin catalyst and an organic amine catalyst.

9. A process for the preparation of the two-component flexible road marking paint according to any one of claims 1 to 8, characterized in that, The method includes the following steps: The A component: the epoxy resin, the polymeric diol, the plasticizer, and the solvent are mixed uniformly under temperature control, the catalyst, the pigment, the filler, the internally mixed glass beads, the dispersing agent, the antifoaming agent, and the optional additives are mixed uniformly, and then the mixture is degassed, packaged, and ready for use; The B component: the modified isocyanate and the isocyanate trimer are mixed uniformly and packaged, and ready for use.

10. Use of a two-component flexible road marking paint according to any one of claims 1 to 8, characterized in that It comprises the following steps: mixing A and B components, spreading or spraying on the road surface to be constructed, forming a coating, sowing glass beads on the surface of the coating, and curing to form a road marking.